Foraminiferal associations and sedimentology of Saudi Middle Jurassic carbonates. Al-Dhubaib. A. J. Department of Earth Science, University College London, ucfbaal@ucl.ac.uk The sedimentological interpretations now pay attention to the high-resolution depositional cyclicity of the carbonates reservoirs. These interpretations have revealed the stratigraphically and biostratigraphically complexity that may result from sea-level induced progradational and retrogradational trends and the diachronous nature of local stratigraphic ranges of shallow-marine species. Utilizing the environmental sensitivity of benthic foraminifera, associated microfossils and macrofossils combined with sedimentology can provide a potentially valuable technique for determining subtle variations in the depositional environment and also provide a proxy for sea-level fluctuations. This study is based on micropalaeontological studies of hundreds of thin sections from three carbonate reservoirs in eastern Saudi Arabia. Additionally, samples were collected from age-equivalent outcrops in central Saudi Arabia. The D6 member of the upper Dhruma Formation contains the Lower Fadhili reservoir. The Baladiyah and Daddiyah members of the Tuwaiq Mountain Formation contain the Upper Fadhili and the Hadriya reservoirs respectively. The assigned age for the Upper Dhruma Formation is late Bathonian to middle Callovian and Middle Callovian for the whole Tuwaiq Mountain Formation. The Middle Jurassic carbonates of Saudi Arabia were deposited on a very extensive submarine platform that extended over most of the Arabian Peninsula. Scattered across the platform were localized deeper areas considered to be intra-shelf basins, and localized highs that formed the sites of stromatoporoid and coral banks. Detailed studies of the vertical successive appearance of various species in samples from cored oil wells and exposed sections, and their relationship to the host carbonate fabrics show two phases within the formations and their contained reservoirs. Firstly, the open marine phase in the lower part of formations with a Lenticulina-Nodosaria-spicule dominated assemblage characterises the deep mud-dominated succession, which is considered as linked with a transgressive dominated phase. Secondly, the restricted marine phase which forms in the upper part of the formations with a shallow marine foraminifera and calcareous algae assemblage characterises the packstone dominated succession. This shallow marine assemblage is characterized by the presence of Palaeopfenderina trochoidea, Meyendorffina bathonica, Andersenolina elongata and Redmondoides lugeoni and is correspondingly attributed to highstand shallowing depositional sequences.

Genetic types of Globigerinoides ruber in the Eastern Atlantic and the Mediterranean Sea

Aurahs, R., Grimm, G., Hemleben, V., Hemleben, C., Kucera., M Institute for Geosciences, University Tübingen, Germany, ralf.aurahs@uni-tuebingen.de Molecular genetic data have in recent years challenged the morphological species concept in planktonic foraminifera. It appears that many, if not all, morphologically defined species hide an additional layer of genetic differentiation. The presence of these "cryptic species‰ has potentially significant impact for the use of foraminifera as proxies and for the interpretation of evolutionary patterns in the fossil record of this group. During the last three years, we have amassed a large dataset on the distribution of genetic types found within the morphospecies Globigerinoides ruber in the Azores Front region and in the Mediterranean Sea. Samples were taken during several seasons, from stations close to the Azores, in the Strait of Gibraltar and in the western and eastern Mediterranean. Partial SSU rDNA sequences from over 300 specimens of G. ruber were obtained. Four distinct genetic types, including one which has not been described before, were identified among the sequenced specimens. Interestingly, three of the genetic types seem to occur throughout the investigated region, with two types often co-occurring within the same plankton net sample. However, seasonal differences in the abundance of these types are observed. The new genotype, which is closely related to G. conglobatus and G. ruber Type II, has so far only been found in the Mediterranean,

suggesting a possible genetic isolation. Our data strongly support the hypothesis that the presence of a pink colouration in specimens of G. ruber does correlate with a defined genetic type. In addition, a phylogenetic analysis of the relationships among the four genetic types and the previously described G. conglobatus indicates that the morphospecies G. ruber consist of two distinct genetic lineages. This distinction is confirmed by the phylogenetic position of the newly described Type and we therefore conclude that the morphospecies G. ruber should be considered as at least two separate species.

Protocols to obtain reproduction and growth of Bulimina marginata under stable and controlled physico-chemical conditions

Barras, C. (1,2), Geslin, E. (1), Duplessy, J.-C. (2), Jorissen, F. (1) (1) Laboratory of Recent and Fossil Bio-Indicators, UPRES EA 2644, Université d’Angers, Angers Cedex, France, and Laboratory of Marine Bio-Indicators Study, Ker Chalon, Ile d’Yeu, France. christine.barras@univ-angers.fr (2) Laboratoire des Sciences du Climat et de l'Environnement, Gif-sur-Yvette, France The relationship between the isotopic composition of the foraminiferal shell and the physico-chemical parameters of the environment in which the organism calcifies is still poorly understood. In fact, the calcification process is influenced by numerous interfering factors, which are hard to distinguish in natural environments. To better understand the effect of one single environmental parameter (temperature) on the isotopic composition of deep-sea benthic foraminiferal shells, we developed a methodology to stimulate reproduction and obtain growth of deep-sea foraminifera under stable physico-chemical conditions. Two different experimental systems were tested to keep constant conditions. The first system is based on the closed circulation of seawater through a reservoir of 20 L and several experiment bottles of 1 L. For each studied temperature (8, 10, 12 and 14°C), one closed system was set up. Each closed system was composed of two experiment bottles containing only adults of Bulimina marginata and one experiment bottle with plurispecific adult faunal assemblages dominated by Bolivina subaenariensis, Hyalinea balthica, Uvigerina peregrina and B. marginata. All specimens incubated in these systems were preliminary marked using the calcein probe to distinguish newly formed calcite. Food (Phaeodactylum tricornutum) was supplied to stimulate reproduction of the adults and growth of the juveniles. The experiments lasted for 3 months. The second system consists of Petri dishes in which half of the seawater is changed every 4 days, replaced by water stored in a big container kept in the dark. Petri dishes containing 30 adults of Bulimina marginata with Phaeodactylum were kept for the same time as the closed systems at each of the four selected temperatures. Preliminary analyses of temperature, pH, salinity, alkalinity, DIC and δ18O measurements of the water along the experiments show that conditions remained stable. Bulimina marginata reproduced and the juveniles started to grow at the four temperatures.

Spatial variability of living (stained) deep-sea benthic foraminifera: comparison between in situ and long-term incubated cores

Barras C., Geslin E., Forestier V., Duchemin G., Jorissen F. Laboratory of Recent and Fossil Bio-Indicators, UPRES EA 2644, Université d’Angers, Angers Cedex, France and Laboratory of Marine Bio-Indicators Study, Ker Chalon, Ile d’Yeu, France. christine.barras@univ-angers.fr Generally benthic foraminiferal ecological experiments in the laboratory are based on replicate samples that are constituted either of aquaria filled with homogenised sediment or of entire cores sampled in the field. The first possibility has the inconvenience to disturb the initial microhabitat distribution. For the second option, eventual differences between the cores due to in situ patchiness are

supposed minimal, and it is generally supposed that they are not responsible for a different evolution of the foraminiferal faunas in the cores. To check this hypothesis, we studied on the one hand the in situ patchiness on 4 replicate cores sampled in May 2004 in the Bay of Biscay at 550 m depth. The living benthic foraminiferal faunas were analysed directly after sampling using the Rose Bengal coloration method. On the other hand, 4 supplementary cores, sampled at the same station during the same cruise, were analysed after 2 years of incubation in the laboratory at 10°C (in situ temperature). During the incubation period, neither food nor oxygen was supplied and parameters such as temperature, salinity and oxygen were controlled. Measures of physico-chemical parameters showed stable temperature and salinity during the experiment and the oxygen penetration depth was the same in situ and at the end of the incubation period. Faunal densities of the 4 in situ cores revealed low patchiness in terms of densities, specific composition and microhabitat. Also the faunal variability (density, specific richness, and microhabitat) in the 4 incubated cores is negligible. However, foraminiferal densities decreased in all incubated cores compared to the initial faunas studied in the in situ cores and some species totally disappeared after 2 years of experimental conditions.

Six degrees centigrade cooling of the East Greenland Current at 3.13 Ma: Evidence from foraminifers

Bartoli, G. (1), Sarnthein, M. (1), Weinelt, M. (1), Andersen, N. (2), Garbe-Schönberg, D. (1) (1) Institute for Geosciences, Kiel University, Kiel; Germany. gretta.bartoli@erdw.ethz.ch (2) Leibniz Laboratory for Radiometric Dating and Stable Isotope Research, Kiel University, Kiel; Germany. Pliocene records from Site 1307 (Labrador Sea) give crucial information on the history of the East Greenland Current as major outflow and, hence, tracer of the Arctic Ocean during the onset of Northern Hemisphere Glaciation (NHG) 3.2-2.6 Ma. A new stratigraphy based on planktic and benthic foraminiferal δ18O has been performed, as well as a foraminiferal Mg/Ca record. Our evidence may solve the "Panama Paradox" as we observed after the closure of Panama at 3.2 Ma an increased in heat transport to the northern high latitudes via the Gulf Stream coeval with a cooling and freshening of the Arctic Ocean. Thus, our results confirm that the closure of Panama did not delay the onset of NHG but fuelled it by increasing the moisture supply to the high latitudes via increased precipitation over Eurasia, which, in turn, lowered the sea surface salinity in the Arctic Ocean, thus promoting sea-ice formation and albedo in the northern hemisphere; being a positive feedback for the NHG.

Variations in upper water-column dynamics in the North Atlantic during the last 20,000 years as revealed by coccolithophorid assemblages

Baumann, K.-H. (1), Meggers, H. (1) and Holtvoeth, J. (2) (1) Department of Geosciences, University of Bremen, Germany, baumann@uni-bremen.de (2) Earth and Ocean Sciences, University of Liverpool, United Kingdom A coccolith-based micropalaeontological investigation of ODP sites 980 and 984 from the Feni and Gardar contour drifts of the northern North Atlantic was conducted in order to reconstruct the pattern and timing of surface circulation changes in the area during the last 20,000 years. In addition, sea-surface palaeotemperature records from both sites were generated at high resolution based on the widely used alkenone palaeothermometer. The down-core variations in coccolith assemblage composition indicate that changes in properties of surface waters in the northern North Atlantic occurred stepwise during the Termination I. Sparse occurrences of coccolithophores together with a higher number of reworked pre-Quaternary species are observed before about 13,500 cal yr BP, indicating harsh environmental conditions and the influence of melt-water. The stepwise increase of North Atlantic Drift water influence from 13,500 to

about 10,000 cal yr BP was associated with the increase in absolute numbers of coccolithophores in the whole area and coincides with maximum Northern Hemisphere summer insolation. A considerable cooling of the surface waters as indicated by a prominent change in the relative abundances of the dominant coccolith species occurred after about 5000 cal yr BP. In addition, a successive increase in millennial-scale perturbations of the surface hydrology towards the Neoglaciation (the last ca. 5000 years) is documented by changes in accumulation of the species, in particular of Emiliania huxleyi. These successive decreases in the numbers of E. huxleyi, as previously described by Giraudeau et al. (2000, EPSL 179), is in phase with recorded Holocene advection of cool, ice-bearing waters from the Greenland-Iceland seas to the North Atlantic. These long-term reorganisations of the surface hydrology are interpreted as the response of the North Atlantic to the combined forces of the solar insolation and the waning Laurentide ice sheet. Giraudeau J., Cremer M., Manthe S., Labeyrie L., Bond G., 2000. Coccolith evidence for instabilities in surface circulation south of Iceland during Holocene times, Earth and Planetary Science Letters, 179, 257-268.

What do coccolith and alkenone variations off NW Africa tell us at Termination I?

Boeckel, B. (1) and Ott, C. (2) (1) Department of Geosciences, Universität Bremen, Bremen; Germany. bboeckel@uni-bremen.de (2) Marum, DFG Research Centre Ocean Margins, Bremen; Germany. Fine-scale differences in morphological traits of certain coccolithophore taxa (e.g. Calcidiscus leptoporus, Emiliania huxleyi, Umbellosphaera tenuis) are well-known. Recent plankton studies suggest that the occurrence of the respective morphotypes is related to distinct hydrographical conditions within the photic zone; thus bearing great potential for palaeoceanographic reconstructions. In this study the abundance of coccolith morphotypes is compared to the alkenone record in order to track the development of changes in the surface water properties off NW Africa during Termination I and the late Holocene (about 18.5 to 1 ka B.P.). Sediment core GeoB 8507 retrieved from the Northwest African continental margin (19°28.5'N, 18°05.97'W, water depth: 2411m) was selected to carry out this high-resolution analysis. Eolian dust input and the marginal influence of intensive biomass production along the NW-African coast likewise characterize to the sedimentation regime. Morphotype abundances correspond well to the surface temperature record derived from alkenones.

Investigating the inflow path of the Indonesian throughflow: A multiproxy reconstruction for the last 150 kyrs

Bolliet, T. (1), Kuhnt, W. (1), Holbourn, A. (1), Beaufort, L. (2), Andersen, N. (3) (1) Institute of Geosciences, Christian-Albrechts-University, Kiel, Germany. (2) CEREGE/CNRS Université Aix-Marseille III, Aix-en-Provence Cedex 04, France (3) Leibniz Laboratory for Radiometric Dating and Stable Isotope Research, Kiel, Germany. The Indonesian Throughflow (ITF) represents a key component in the global thermohaline circulation through the transport of Pacific thermocline waters into the Indian Ocean. Thus, understanding its temporal variability is essential to reconstruct past changes in the global circulation system as well as climatic variations in the Australasian region. ITF variability is strongly linked to monsoon and ENSO dynamics, which modify thermocline depth in the West Pacific Warm Pool and alter the ITF vertical profile and current flow intensity through the Indonesian seas. In this study, we use multi-proxy records (multispecies foraminiferal δ13C, δ18O, Mg/Ca, coccoliths and benthic foraminiferal assemblages and X-ray fluorescence scanning) from a new core recovered in 1575 m water depth off the eastern coast of Mindanao island (Philippines) in July 2006 during the Marco Polo II cruise. IMAGES Core MD06-3067, located within the main inflow path of the ITF at the north-eastern edge

of the West Pacific Warm Pool, provides a unique archive to closely track changes in sea surface temperature, depth of thermocline, palaeoproductivity and land-derived flux over the last 150 kyr (MIS 6 to actual). Preliminary results indicate complete recovery of a carbonate rich sedimentary succession with average sedimentation rates of 10-12 cm/kyr. Terrigenous flux proxies (Titanium and Iron counts from XRF analysis) show a good match with boreal summer insolation variability. Primary production calculated from coccoliths abundance exhibits higher values during glacials; and thus may be linked to monsoonal and ENSO-related processes affecting thermocline depth.

Foraminiferal vertical distribution related to macrofaunal sediment bioturbating modes: new insight from axial tomodensitometry

Bouchet, V. (1,2), Sauriau, P.-G. (1), Debenay, J.-P. (3), Mermillod-Blondin, F. (4), Amiard, J.-C. (5) and Dupas, B. (6) (1) CRELA (UMR 6217 CNRS-IFREMER-ULR), L'Houmeau, France, vincent.bouchet@ifremer.fr (2) Laboratory of Recent and Fossil Bio-Indicators, UPRES EA 2644, Université d’Angers, Angers Cedex, France (3) IRD, UR 055 Palaeotropique, Centre de Nouméa, Nouméa cedex, New Caledonia (4) LEHF (UMR 5023 CNRS-Université Lyon I), Campus de la Doua, 6 rue Dubois, 69622, Villeurbanne, France (5) Université de Nantes, SMAB (EA2160), Nantes cedex 3, France (6) Service de Radiologie, CHU Hôtel-Dieu, 44000, Nantes, France Benthic foraminifera occupy a range of epibenthic to deep infaunal microhabitats. Bioturbation, resulting from the activity of burrowing organisms into the sediment, has significant effects on both sedimentary structure and biogeochemical processes, affecting infaunal microhabitats. Bioturbation effects depend on the feeding and burrowing modes of macrofaunal species, which are classified in functional groups depending on their bioturbating mode. The aim of this study was to determine the relationship between the vertical distribution of benthic foraminifera and the type of macrofaunal bioturbation. At two intertidal sites, 30cm deep sediment cores were collected: one (site A) on a bare mudflat, the other (site B) in an oyster culture. Each core was studied using a new method for the quantification of biogenic structures by axial tomodensitometry (CAT scanner). CAT scan allowed discrete quantification of the volume occupied by macrofaunal biogenic structures. After scanning analyses, cores were sliced to determine the vertical distribution of foraminiferal and macrofaunal species. At site A macrofaunal assemblages comprised polychaetes and bivalves. The sediment was highly bioturbated by bivalve-siphons at depth 0-4cm, by bivalve-shell-body at depth 4-8cm, and throughout the sedimentary column by nereid polychaete. Six hundred and fifty five living foraminiferal individuals belonging to 5 major species were found, mainly infaunal with only 21% in the first centimetre of sediment, 48% in the 1-10cm slice and 31% in the 10-30cm slice. Haynesina germanica inhabited only superficial sediments whereas Ammonia tepida and Cribroelphidium excavatum lived both epi- and infaunally. At site B, macrofaunal assemblages were characterised by small spionid polychaetes, mainly bioturbating the 0-1 cm slice. Foraminifera were mainly distributed in the first centimetre of sediment (87%) but only 23 living individuals belonging to 3 major species were recorded. Comparisons between the two sites showed that vertical distributions of foraminifera were related to bioturbation by macrofauna. These results also demonstrated the key role played by the different macrozoobenthos functional groups. In sediment slightly bioturbated by spionid polychaetes, benthic foraminifera were mainly concentrated in surficial sediment whereas in sediment strongly bioturbated by nereid polychaetes and large bivalve species, living foraminifera were distributed through the entire sedimentary column.

Milankovitch Scale Cyclicity in the Eocene Southern Ocean - An integrated micropalaeontological and geochemical approach

Burgess C.E. and Pearson P.N. School of Earth, Ocean and Planetary Sciences, Cardiff University, Wales burgessce@cf.ac.uk The middle Eocene is a crucial time period in understanding the link between Antarctic ice development, global climate and oceanographic systems. Studies suggest that ice had begun to form on Antarctica by the middle Eocene but the extent of the ice and the influence it exerted over local and global ocean currents and marine ecological systems is not well understood. This study uses an integrated approach combining micropalaeontological and geochemical techniques to address this problem. The middle Eocene Hampden Formation of New Zealand shows clear sedimentary cyclicity on a Milankovitch timescale. The clay rich sedimentary facies has resulted in excellent preservation of calcareous micro- and nannofossils and of organic walled microfossils. This is key in ensuring that assemblages are as complete as possible and that geochemical results are little influenced by digenesis. High resolution sampling within the Hampden formation has enabled the examination of micropalaeontological and geochemical evidence for environmental and oceanographic change through these cycles. Studies of faunal assemblages of planktonic and benthic foraminifera, dinoflagellates and calcareous nannofossils have been carried out alongside geochemical analysis of foraminiferal calcite in the same samples. Combining all these lines of evidence enables the reconstruction of variations in current systems, ecology and climate both locally to the site and regionally, through the sedimentary cycles. The geochemical results show cyclic variability in planktonic and benthic foraminiferal oxygen and carbon isotopes at the same frequency as the sedimentary cycles. Combining Mg/Ca data with the oxygen isotopes for benthic foraminifera demonstrates that the variability in oxygen isotopes can be accounted for by seawater temperature change and that there is no evidence for a significant volume of ice on Antarctica in the early middle Eocene. Floral and faunal assemblage data supports this temperature variability and also suggests a global rather than local cause.

The water column dynamic in response to the environmental perturbations at the T/J boundary: data from Austria and England

Clémence, M. E. (1), Gardin, S. (1), Bartolini, A. (1), Beaumont, V. (2), Paris, G. (3) (1) Laboratory of Palaeobiodiversity and palaeoenvironments, P. & M. Curie University, Paris cedex 05, France, clemence@cr.jussieu.fr (2) Department of Geological and Geochemical, IFP, Malmaison cedex, France. (3) Department of Geochemical-Cosmochemical, IPGP, 4, Paris cedex 05, France. The Triassic-Jurassic (T/J) transition is a crucial time for both Earth's environment and biota. Global environmental change across the T/J is marked by two closely spaced negative δ13C anomalies. The first one is coincident with the end-Triassic biotic crisis, showing a perturbation of the global carbon cycle. The second 'main' isotope excursion occurs in the Early Hettangian and it is associated with a relative sea-level increase, high burial organic matter, major flora changes and faunal (radiolaria and ammonites) extinction. Coeval volcanism led to the formation of a large igneous province, the Central Atlantic Magmatic Province (CAMP). The role of the marine productivity before, during and after the mass extinction and its possible link with the volcanism was investigated in the sedimentary record of Tiefenbachgraben and Kendelbachgraben sections (Nothern Calcareous Alps) and Doniford section (Somerset, UK). Our approach consists of synecological analyses of benthic foraminifers and calcareous nannofossils integrated with geochemical analyses, in order to better understand the water column dynamic during the T/J boundary.

Late Rhaetian calcareous nannofossil and benthic foraminifer assemblages are abundant and diverse. The presence of calcareous dinoflagellate cysts (P. triassica; Thoracosphaera sp.; C. tripartita; Nannoconus sp.; C. tollmaniae), associated with the first coccolithophores (C. minutus, C. primulus, A. koessenesis) and the presence of large-sized benthic foraminifers (Nodosaria sp., Ichtyolaria sp., Eoguttulina sp., Prodentalina sp., Lenticulina sp.) indicate optimal environmental conditions and efficiency of the biological carbon pump. The T/J interval marks the beginning of a marine environmental deterioration process characterized by a decrease of surface water productivity as attested by a major drop in calcareous dinoflagellate abundance, coupled with disappearance of Coccolithophores. In the same time, the new species S. punctulata, probably profiting of the progressive disappearance of P. triassica (dominant in the Rhaetian assemblages) occurs. At the sea-bottom, benthic foraminifer assemblages are affected by a severe decrease of Rhaetian fauna and the appearance of agglutinated (Trochammina sp., Ammobaculites sp., Haplophragmoïdes sp.) and opportunistic taxa (Reinholdella sp.; Lingulina tenera). These results attest of a highly perturbed environment, stress conditions and a biological carbon pump severely affected by the T/J mass extinction event.

Spatial distribution of coccolith in a transect from an extremely oligotrophic gyre to an intense upwelling in subtropical South Pacific

Couapel, M.J.J. and Beaufort, L. CEREGE/CNRS Université Aix-Marseille III, BP 80, 13545 Aix-en-Provence Cedex 04, France. couapel@cerege.fr Water samples were collected at multiple depths in the photic zone in a transect from the Marquises archipelagos to the Chilean upwelling, via the South Pacific gyre, during the BIOSOPE cruise in 2004. Based on full taxonomic identification of the coccolithophore community, we describe the spatial distribution of the species according to depth and fertility. The coccolith concentration ranges from 1200 to about 420000 coccosphere/l, while the species richness ranges from 2 to 43. The stock is correlated to the total chlorophyl a, and the highest specie richness is reached at each station along the transect in the deep chlorophyll maximum. The highest number of coccospheres and the greatest species richness are found in the margin of the Chilean upwelling system. The low-nutrient, low-chlorophyll South Pacific gyre, often described as the world poorest desert, is in fact inhabited by a deep coccolithophore community living down to 300 m depth. The concentration of this community, which is composed of 15 species, reaches about 20000 coccosphere/l.

An investigation into the life history of Streptochilus

Darling, K. (1) Kasemann, S. (1), Thomas, E. (2), Wade, C. (3) and Seears, H (3) (1) Grant Institute of Earth Science, University of Edinburgh, UK Kate.Darling@ed.ac.uk (2) Department of Geology & Geophysics, Yale University, USA (3) Department of Genetics, University of Nottingham, UK Specimens of the biserial planktonic foraminiferal genus Streptochilus were collected 540 nautical miles offshore in the central Arabian Sea during the summer monsoon of 2003. Samples were collected from 5m water depth in waters with an average depth of 3,500 metres. All living specimens had bright orange coloured cytoplasm and sizes ranged from juvenile to fully mature. Ancestral relationships were determined by comparing their small subunit ribosomal DNA sequences with those from closely related and morphologically similar taxa. Living benthic foraminifers are commonly found suspended in the plankton in high energy turbulent waters, particularly over shallow shelf regions. Expatriation into the open ocean may also occur providing there is sufficient turbulence to keep them in suspension. In addition, there is also the possibility of propagule transport into the open ocean. Whether Streptochilus is solely planktonic has been continually questioned and we explore the

life history of Streptochilus using molecular, morphological, ecological and geochemical evidence to find clues to its ancestry and ecological habit.

Test microevolution in planktonic foraminifera in response to environmental changes during the Cenomanian-Turonian interval

Desmares, D. (1), Grosheny, D. (2) and Beaudoin, B. (3) (1) Université Paris-Sud, UMR8148, Orsay Cedex; France. delphine.demares@u-psud.fr (2) Université Louis Pasteur, EOST, UMR7561, Strasbourg Cedex; France. (3) Ecole des Mines de Paris, Paris; France. Major oceanic changes occur during Cenomanian-Turonian period, including the global expansion of the oxygen minimum zone (OAE2) and the disappearance of Rotaliporinae, complex keeled foraminifera which previously occupied deep oceanic waters. In the Western Interior Basin, two species of Rotalipora are recorded: Rotalipora cushmani and Rotalipora greenhornensis. Associated with these keeled morphotypes, two forms of the genus Anaticinella occur. These inflated morphotypes are characterised by a discrete peripheral keel which is not expressed on each chamber or even totally absent. However, they preserve the same characteristics than Rotalipora (supplementary apertures, coiling ratios). Anaticinella multiloculata would derive from R. greenhornensis and Anaticinella planoconvexa from R. cushmani by simply losing their keels, in response to the OAE2. This deterioration of the development corresponds to a modification of the growth speed. In the case of Anaticinella, this one is slowed down. Anaticinella preserves youthful characters but has the same size as Rotalipora. Such transformations during the ontogeny development agree with heterochrony like neoteny sensu Gould (1977). High resolution correlations across the North American basin also indicate that transitional forms between Whiteinella praehelvetica and Helvetoglobotruncana helvetica are present in the terminal Cenomanian, during the acme of oceanic anoxic event. Whereas the first chambers of these morphotypes are globular, the two or three last chambers of the final whorl have a peripheral keel. In term of taxonomy, transitional forms are difficult to attribute to such or such species because there is a continuum between W. praehelvetica and H. helvetica. Transitional forms occur within anoxic microfacies whereas H. helvetica appears in highly oxygenated limestones ; thus their occurrences are constrained by oceanic changes. These examples of sympatric speciation conduct to general questions about the concept of species and genus during the geological times. If for the Cretaceous, keeled or globular forms (as for Rotalipora/Anaticinella) are not classified in a same genus, different morphotypes are currently regrouped in same genus by the micropalaeontologists for the Palaeogene and Neogene (as for Globorotalia crassaformis/Globorotalia ronda). Gould, S.J., 1977. Ontogeny and phylogeny. The Belknap press of Harvard University Press, Cambridge, USA. 501 pp.

Seasonality of living benthic foraminifera from the continental shelf of the Bay of Biscay: comparison with phytoplankton blooms

Duchemin, G. (1,2), Jorissen, F.J. (1,2), Le Loc‚h, F. (3), Andrieux-Loyer, F. (4), Hily, C. (3) and Philippon, X. (4) (1) Laboratory of Recent and Fossil Bio-Indicators, UPRES EA 2644, Université d’Angers, Angers Cedex, France (2) Laboratory of Marine Bio-Indicators Study, Ker Chalon, Ile d’Yeu, France (3) Institut Universitaire Européen de la Mer, UMR 6539 CNRS, Plouzané; France (4) IFREMER Centre de Brest, Plouzané, France

Six stations of the continental shelf of the Bay of Biscay have been investigated for living foraminiferal faunas during three successive seasons (spring, summer and autumn 2002). At outer shelf stations, the spring situation is characterised by a strong dominance of Nonionella iridea and high abundances of Bulimina marginata, Hanzawaia boueana and Nonionella turgida. Nonionella iridea presents a density gradient with an absence at the station closest to the coast and high values in stations close to the shelf break. This situation can be explained by the presence in early spring of an important phytoplanktonic bloom, mainly composed of coccolithophorids, over the shelf break, an observation that is supported by the strongest particles flux values in stations close to the shelf break (18.5 g m-2 h-1) and lower value in a station closer to the coast (6.8 g m-2 h-1). This high flux of labile organic matter is corroborated by the high density of suspension feeders (macrofauna) in outer shelf stations. In autumn, foraminiferal faunas are characterised by Cassidulina carinata, Uvigerina peregrina and Siphotextularia flintii on the outer shelf and by Hyalinea balthica on the inner shelf. The densities of the first three taxa are again subject to a gradient, but in this case with increasing densities from stations nearest to the coast to stations close to the shelf break to. In summer, the faunas have intermediate characteristics. This strong spatial and temporal variability could be explained by the phytoplankton blooms that occur over the shelf break in spring and in the more coastal areas in summer, and by the input of river-born refractory organic matter from the continent. The intensity of the faunal response appears to be controlled by the distance to the primary production maxima and to the quality of organic matter. We suggest that the differential response of the various species could be explained by the composition of the phytoplankton blooms, with N. iridea being associated with blooms dominated by coccolithophorids and C. carinata and U. peregrina associated with blooms dominated by dinoflagellates, and by the quality of organic matter, with H. balthica being associated with more refractory organic matter.

Rapid low latitude palaeoceanographic change coupled to high latitude glaciation through the Eocene-Oligocene boundary

Dunkley-Jones, T. (1), Bown, P.R. (1), Pearson, P. N. (2), Wade, B. S. (3), McMillan, I. K. (2) Nicholas, C.J. (4) and Coxall, H. C. (2) (1) Department of Earth Sciences, University College London, UK. tom.dunkleyjones@ucl.ac.uk (2) School of Earth, Ocean and Planetary Sciences, Cardiff University, Cardiff, UK. (3) Department of Geological Sciences, Rutgers, Wright Laboratory, Piscataway, USA. (4) Department of Geology, Trinity College, University of Dublin, Ireland. The Eocene-Oligocene transition period witnessed the most significant climatic change in the Cenozoic with a fundamental reordering of the planet's oceanic and atmospheric circulation, rapid cooling of deep and high-latitude waters and the formation of continental scale ice sheets on Antarctica (Zachos et al., 1992). Recent attention has focused on the rapid and near-coincident increase in deep-water oxygen and carbon isotopes, a drop in Calcium Carbonate Compensation Depth (CCD) of over a kilometre (Coxall et al., 2005) and an increase in Southern Ocean productivity in the earliest Oligocene (Salamy and Zachos, 1999). We present results from two on-shore boreholes in southern Tanzania that recovered a 200m sequence of hemi-pelagic clays through the Eocene-Oligocene Boundary. Preservation of both foraminifera and calcareous nannofossils is exceptional, with the preservation of a remarkably diverse hetero- and holococcolith assemblage. High-resolution calcareous nannofossil assemblage data show a significant shift in the calcareous phytoplankton community occurring in phase with the major ~1 per mil increase in seawater δ18O, which is attributed to the rapid growth of the Antarctic ice-sheet. The most marked feature of this record is a ~10kyr step change in nannofossil assemblages coincident with the synchronous extinction of the Hantkeninidae planktonic foraminifera and a range of larger, shelf-dwelling, benthic foraminifera taxa. This record shows the intimate connection between low latitude palaeoceanography and Antarctic glaciation and provides a new correlation between events at the Eocene-Oligocene boundary and global climate change.

Coxall, H.K., Wilson, P.A., Palike, H., Lear, C.H. and Backman, J., 2005. Rapid stepwise onset of Antarctic glaciation and deeper calcite compensation in the Pacific Ocean. Nature, 433: 53-57.

Salamy, K.A. and Zachos, J.C., 1999. Latest Eocene Early Oligocene climate change and Southern Ocean fertility: inferences from sediment accumulation and stable isotope data. Palaeogeography Palaeoclimatology Palaeoecology, 145(1-3): 61-77.

Zachos, J.C., Breza, J.R. and Wise, S.W., 1992. Early Oligocene ice sheet expansion on Antarctica: Stable isotope and sedimentological evidence from Kerguelen Plateau, southern Indian Ocean. Geology, 20: 569-573.

Paired δ44/40Ca and Mg/Ca temperature estimates of N. pachyderma (sin.) in the Nordic Seas

Eisenhauer, A. (1), Kozdon, R. (1,2) , Weinelt, M. (2), Hippler, D. (3) (1) Leibniz Institute for Marine Sciences, IFM-GEOMAR, Kiel, Germany (2) Geological-Paleontological Institute, Christian-Albrechts-Universität zu Kiel, Kiel, Germany, (3) Faculty of Earth and Life Sciences, Vrije Universiteit, Amsterdam, The Netherlands A reassessment of the temperature sensitivity of the Mg/Ca and δ44/40Ca signal in planktonic foraminifera N. pachyderma (sin.) from Holocene Nordic Seas sediment surface samples covering an SST-range in between 0°C to 8°C reveals that lowest Mg/Ca and δ44/40Ca ratios are recorded in water temperatures at ~3.5°C. Based on this new calibration, we found that tests of N. pachyderma (sin.) can be subdivided into two groups which differ in their suitability as temperature proxy recorder. Mg/Ca and δ44/40Ca ratios of N. pachyderma (sin.) from the Norwegian Sea (Group I) reflecting water temperatures above about 3.5°C are positively correlated match existing Mg/Ca temperature calibrations. In contrast, Mg/Ca and δ44/40Ca proxy data of N. pachyderma (sin.) originating from cold (<3.5°C), low saline (<33.5 ‰) Arctic Domain and polar waters (Group II) are inversely related to temperature. Group II proxies are decoupled from each other, forming an almost parabolic Mg/Ca temperature relation. This non-passive character of N. pachyderma (sin.) at the 'cold temperature end' can be reconciled by a model assuming that the foraminiferal test composition of N. pachyderma (sin.) is defined by temperature dependent proportions of two different calcite phases produced in this foraminiferal species. A binary mixing process of two distinctively different calcite endmembers is clearly visible in our data by identical temperature dependent slopes of δ44/40Ca and Mg/Ca data. Above about 3.5°C, the mixing process between the two calcite endmembers follows a positive correlation with temperature and may represent part of the trace metal homeostasis during moderate temperatures. The inverse Mg/Ca-temperature response of the Group II data below ~3.5°C may then be interpreted to reflect different biomineralization pathways meant to inhibit the decrease of the Mg-content below a certain threshold value with decreasing temperatures.

Foraminiferal organic linings: Molecular and isotopic composition

Ernst, S. R. (1), Fhlaithearta, S. Ní (1), Renema, W. (2), de Lange, G. J. (1), Van der Zwaan, G -J. (1), Reichart, G -J. (1,3) (1) Faculty of Geosciences, Utrecht University, Utrecht, The Netherlands (2) Nationaal Natuurhistorisch Museum, Leiden, The Netherlands (3) Alfred Wegener Institute for Polar and Marine Research, Bremenhaven, Germany Fossil foraminiferal carbonate has long been used by palaeoclimatologists to decipher past changes in physical and chemical properties of seawater. Empirical relationships, derived from core top data and culturing experiments, relate changes in isotopic values and trace metal composition to key environmental parameters such as temperature, salinity and seawater trace metal concentrations. Foraminiferal organic linings, being composed of recalcitrant organic matter, are also preserved in the

fossil record and as such represent a source of information complimentary to foraminiferal carbonate. Organic linings, generally found between the carbonate test and the cytoplasm, require careful isolation and cleaning to avoid contamination. Linings are isolated by allowing the carbonate to dissolve in the presence of an ion exchange resin. Once isolated and cleaned, the linings of several species of recent benthic foraminifera are analysed by pyrolysis-gas chromatography-mass spectroscopy. This technique identifies the macro-molecular composition of the organic linings, thus allowing us to determine any inter-species variations and the degree of diagenesis which may have taken place during fossilisation. Measuring the stable isotopic composition (δ13C, δ18O) of the organic linings further allows us to constrain the relationship between carbonate test, organic lining and ambient seawater.

Central Arctic Ocean planktonic foraminifera: the Late Pleistocene record from the IODP ACEX Site

Eynaud, F. (1), Cronin, T. (2), Marry, Y. (1), Mavel, J. (1), Smith, S. A. (2) (1) Département Géologie et Océanographie, UMR-CNRS "EPOC" 5805, Université Bordeaux I, Talence, FRANCE (2) 926A USGS National Center, Reston, Virginia USA The Arctic planktonic foraminifera population has been studied throughout the top 26 meters in Hole 4C from IODP Expedition 302 (ACEX). We focus our observations within the fraction >125µm. Below one meter (MCD depth), most samples reveal microfossil assemblages barren of calcareous microfossils. Planktonic foraminifera occur in high absolute concentrations only within the uppermost fifty centimetres of the core. Assemblages recovered are virtually monospecific, completely dominated by Neogloboquadrina pachyderma. The N. pachyderma plexus, however, shows distinctive intraspecific morphological variability. This variability has been studied based on shape variations (number of chambers in the final whorl, chamber sphericity), size, and coiling direction. Five morphotypes were identified within the sinistral population and two morphotypes were distinguished in the dextral forms. Detailed morphological and stable isotopic investigations have been conducted on the different morphotypes. We suggest that the identified morphotypes belong to a species complex as it has been demonstrated from different parts of the world ocean on the basis of molecular approaches (e.g. Darling et al., 2000). Especially we believe that, as shown for austral populations of N. pachyderma (s), the central Arctic Ocean populations identified represent different genotypes. This idea still needs to be tested by molecular approaches and represents a challenge for classical micropalaeontological approaches largely based on a morphological concept of species. We furthermore argue that large morphotypes identified could be tracers for North Atlantic sub-surface water penetrating into the central Arctic Basin. Darling, K.F., Wade, C.M., Steward, I.A., Kroon, D., Dingle, R. & Leigh Brown, A.J., 2000. Molecular evidence for genetic mixing of Arctic and Antarctic subpolar populations of planktonic foraminifers. Nature 405, 43ˆ47.

Live and dead foraminiferal faunas from the Saint-Tropez Canyon (Bay of Fréjus): „In situ” and „culture” observations

Fontanier, C. (1), Jorissen, F. (1), Geslin, E. (1), Zaragosi, S. (2), Duchemin, G. (1), Laversin, M. (1), Gaultier, M. (1) (1) Laboratory of Recent and Fossil Bio-Indicators, University of Angers, Angers Cedex, France, and Laboratory of Marine Bio-Indicators Study, Ker Chalon, Ile d’Yeu, France christophe.fontanier@univ-angers.fr

(2) Department of Geology and Oceanography, University of Bordeaux, CNRS UMR 5805 EPOC, Talence Cedex, France. Living (rose Bengal stained) and dead foraminiferal faunas have been studied at a 373 m deep station (CAMT-5 station) in the Saint-Tropez Canyon (Bay of Fréjus, France). Bioceonoses and thanatoceonoses were investigated in the >150 µm fraction of two cores collected with a classical multi-corer. A first („in situ”) core was fixed with ethanol and rose Bengal at the time of the sampling, whereas a second („culture”) core was incubated in the laboratory for 2.5 years. Both cores present similar thanatoceonoses that are partially contaminated by neritic foraminifera transported from adjacent continental shelves. The sedimentological analysis (X-Ray, colorimetry, granulometry) of a third core reveals neither graded sediments nor erosional surfaces. Abundant organic remains (algal fragments) are detectable along the cores in muddy sediments. These observations are indicative of a continuous input of fine-grained sediment as well as resuspended organic matter (algal remains) originating from shallower areas, and preclude scenarii of turbiditic events. The living „in situ‰ fauna is characterized by an elevated diversity and moderate equitability. The high abundance of intermediate and deep infaunal taxa (Uvigerina elongatastriata, Bolivina alata, Melonis barleeanus, Globobulimina spp. and Chilostomella oolina) suggests that the living foraminiferal fauna has adapted to the focusing of important amounts of organic matter in our canyon environment. During the two and a half years of incubation, the „culture‰ core suffered high salinity and oxygen changes; salinity ranged from 35 to 62 psu whereas oxygen concentration at the sediment-water interface was almost zero when the „culture‰ core was sampled. It was no surprise, that all dominant taxa found in the „in situ” core had disappeared in the „culture” core. Surprisingly, only Rosalina bradyi (Cushman, 1915) survived these extreme adverse experimental conditions. It was mainly found close to the strongly hypoxic sediment-water interface. Its density (516 ind/100cm2) was about two orders of magnitude higher than in the „in situ” core (3 ind/100cm2). R. bradyi was able to reproduce and grow in culture conditions, suggesting that this normally neritic taxon is able to tolerate major changes of salinity and bottom water oxygen concentration, and to survive prolonged periods of adverse conditions.

Live (stained) Foraminifera from the Gulf of Lions (NW Mediterranean Sea): density, diversity, microhabitat and environmental settings.

Fontanier, C (1), Lansard, B. (2), Mouret, A. (3), Kerhervé, P. (4), Buscail, R. (4), Schmidt, S. (3), Zaragosi, S. (3), Ernoult, E. (1, 3), Artero, C. (4), Levasseur, J. (3), Gautier, M. (1), Maltese, L. (5), Berné, S. (5), Rabouille, C. (2), Jorissen, F. (1) (1) Laboratory of Recent and Fossil Bio-Indicators, UPRES EA 2644, Université d’Angers, Angers Cedex, France and Laboratory of Marine Bio-Indicators Study, Ker Chalon, Ile d’Yeu, France christophe.fontanier@univ-angers.fr (2) Laboratoire des Sciences du Climat et de l'Environnement, UMR 1572 CEA-CNRS, Gif-sur-Yvette Cedex, France (3) Department of Geology and Oceanography, University of Bordeaux, UMR 5805 CNRS, Talence Cedex, France (4) Centre de Formation et de Recherche sur l‚ Environnement Marin, University of Perpignan, UMR 5110 CNRS, Perpignan Cedex, France (5) IFREMER, Département Géosciences Marines, Plouzané Cedex, France We present an ecological study of live (rose-Bengal stained) foraminifera from 6 deep-sea stations sampled on an interfluve between the Grand-Rhône Canyon and the Petit-Rhône Canyon. The 6 stations describe a bathymetric transect from 343 to 1987 m depth. Their investigation during the BEHEMOTH cruise in September 2006 provided a consistent dataset of environmental parameters. It allowed us to investigate some major aspects of the ecological patterns of live foraminiferal faunas that we encountered along the slope. Foraminiferal density and specific richness decrease generally with depth as an effect of organic matter flux decrease. The lowest values (S = 27 taxa; D = 87 foraminifera/core) are recorded at the deepest site (station A, 1987 m) where pore water oxygenation is the highest and organic export is

supposed to be minimal. The highest values are recorded at the Station E (552 m) with a specific richness of 61 taxa and a foraminiferal density of 401 individuals/core. At the shallowest station (station F, 343 m) where sediments are glauconitic sands (cascadite deposits), foraminiferal standing stock and diversity are lower. When we analyse the specific composition at all stations, live foraminiferal faunas are characterised by high abundance of fossilizing and non fossilizing agglutinated taxa with significant occurrence of epilithic species. Those epilithic taxa encountered at deeper stations may testify organic matter in suspension at the sediment-water interface. Bigenerina nodosaria (arenaceous taxon), Uvigerina peregrina and Uvigerina mediterranea (both hyaline species) which dominate the shallower sites (stations F, E and D between 343 m and 745 m) plead for a relatively high input of organic detritus in the upper sediment. Our results show also that oxygen penetration depth does not control the foraminiferal distribution at all our interfluve environments. The availability of food in the upper sediment (organic detritus), the putative abundance of organic compounds in suspension at some sites, and the granulometric framework of the upper sediment are important parameters controlling foraminiferal microhabitats at our interfluve stations.

Foraminiferal geochemical and isotopic proxies of the ocean carbonate system

Foster, G.L. (1), Schmidt. D.N. (2), and Elliott, T. (1) (1) Bristol Isotope Group, Department of Earth Sciences, University of Bristol, UK g.l.foster@bristol.ac.uk. (2) Department of Earth Sciences, University of Bristol, UK. Atmospheric CO2 is an important greenhouse gas that regulates the Earths climate on geological and shorter timescales. Proxy data for the ocean carbonate system in the past have a crucial role to play in the understanding how CO2 is partitioned between the ocean and atmosphere. Of particular importance in this regard is the suite of proxies based on the isotopic and trace element composition of foraminifera. Amongst these proxies δ11B, B/Ca, and U/Ca are currently receiving most attention. "Vital effects" in both stable isotope ratios and trace element abundances complicate their application with regard to the carbonate system of the past ocean. For instance, δ11B is thought to be influenced by the pH of the microenvironment surrounding a living foraminifer whilst trace element incorporation into foraminiferal carbonate is thought to be affected by, amongst others, shell growth rate, pH, salinity and species-specific biological effects. Careful calibrations are therefore required before these proxies can be confidently applied to reconstruct past environments, but conversely, such calibrations may also provide insights into the calcification mechanisms and physiology of the studied foraminifer. Much of the resistance to the exploitation of these carbonate system proxies arises as a consequence of analytical difficulty. For example, foraminifera typically contain 5 to 20 ppm boron and the expected changes in ocean chemistry require a measurement of its isotopic composition to better than 0.5 ‰. To this end, we have developed a number of new analytical methodologies and strategies to meet this challenge. We will present a summary of our efforts to calibrate a number of carbonate system proxies in planktic and benthic foraminifers (in particular δ11B and B/Ca) and several examples illustrating how these proxies have the potential to shed light on the mechanisms and magnitude of the redistribution of carbon between the atmosphere, surface and deep ocean reservoirs at several key times in the past.

Laboratory study of benthic foraminiferal responses to oxygenation conditions and food supply.

Geslin, E., Jorissen, F. Laboratoire des Bio-Indicateurs Actuels et Fossiles, Angers, France emmanuelle.geslin@univ-angers.fr Marine and coastal environments are influenced by anthropogenic and climatic impacts. One of the consequences is eutrophication and consequently a decrease of the oxygen content in the sediment.

Benthic communities are strongly influenced by low oxygenation, but also by food supply, which are inter-correlated. Yet field investigations difficulty separate between the influence of food and oxygen content on the benthic assemblages. Laboratory experiments are therefore necessary to understand the response of benthic foraminiferal faunas to low oxygen conditions and to food supply. In the Rhône delta (Mediterranea, France) twenty-two multitube cores (0-5cm) were collected at 60 m water depth. Four cores were treated with Rose Bengal to document the initial assemblages and the patchiness. Half of the remaining cores were incubated under oxygenated conditions (=first series) whereas the other cores were incubated under anoxic conditions (=second series). Food was added to half of the oxic and anoxic samples. Each condition was replicated. After 10 and 40 days of the experiment, oxygen and pH profiles were measured and cores were sliced and treated with Cell Tracker Green probe in order to distinguish accurately alive from dead specimens. Oxygen profiles show well oxygenated cores in the first series. In the second series, anoxic conditions were recorded after 10 days, but after 40 days some cores were reoxygenated. Preliminary results of the foraminifera analysis address the faunal density and composition in the uppermost centimetre of the sediment. After 10 days, it appears that foraminiferal communities were unchanged regardless different ambient conditions. In contrast after 40 days higher densities are recorded under oxic conditions. Eight species are dominant: 4 agglutinated species (Clavulina cylindrica, Eggerella scabra, Lagenamina spp. and Nouria polymorphinoides) and 4 hyaline species (Cassidulina carinata, Nonionella turgida, Nonion scaphum and Rectivugerina phlegeri). Under oxic conditions with or without food supply a strong increase of Eggerela scabra is observed. Under anoxic condition, the dominant species are Nonionella turgida and Nonion scaphum and occasionally Nouria polymorphinoides.

Holocene biostratigraphy and palaeoenvironmental changes in the Black Sea based on calcareous nannoplankton

Giunta, S. (1), Morigi, C. (1), Negri, A. (1), Guichard, F. (2), Lericolais, G. (3) (1) Dipartimento di Scienze del Mare, Università Politecnica delle Marche, Ancona, Italy. s.giunta@univpm.it (2) Laboratoire des Sciences du Climat et de l'Environnement, Gif-sur-Yvette, France (3) IFREMER - Centre de Brest, Géosciences Marines, Plouzane cedex, France In this study, detailed micropalaeontological analyses were carried out on 270 samples from eight piston cores collected in the Black Sea. The primary goal was to elucidate the Late Quaternary evolution of the Black Sea, specifically to refine its biostratigraphy and to explore the Holocene palaeoenvironmental changes. Three intervals were recognized in all the cores studied, irrespective of whether they were from the basin or the shelf. These intervals are characterized, from old to young, by the spotty occurrence, the presence and the local acme of Emiliania huxleyi respectively. Moreover, the species Braarudosphaera bigelowii is, in contrast to the younger units, absent in the oldest unit. The co-occurrence of the two marine species E. huxleyi and B. bigelowii suggests a shift from fresh-brackish water to low-salinity marine conditions in the Black Sea. The spotty and very rare occurrence of E. huxleyi in the lowermost unit is reported here for the first time. Two hypotheses are suggested: the presence of reworked specimens from Eemian outcrops, or the presence of low salinity waters also during the "lacustrine" phase of the basin. Another feature observed in almost all the cores is the presence of a multi-lamina aragonite level in the upper part of the Ecozone 3, which functions as a marker for basin-wide correlations. The parallel study of water samples and surficial sediment assemblages demonstrates the presence of Syracosphaera lamina in the surface water samples and its absence in the sediments, suggesting dissolution in the water column. On the other hand, the occurrence of B. bigelowii in all cores and its near-absence in water and in recent sediment samples suggest a change in water conditions during recent times.

Stable isotopic composition of deep-sea benthic foraminifera from the North-East Atlantic Ocean

C. Griveaud1, F. Jorissen1, E. Michel2, C. Fontanier1 1 Laboratoire d'Étude des Bio-indicateurs Actuels et Fossiles, UPRES EA2644, Université d'Angers, 2bd Lavoisier, 49045 Angers Cedex France. clementine.griveaud@univ-angers.fr 2 Laboratoire des Sciences du Climat et de l'Environnement, CNRS-CEA, Allée de la Terrasse 91198 Gif/Yvette Cedex France The stable isotopic composition (δ13C, δ18O) of living benthic foraminifera has been studied in three deep-sea areas of different trophic conditions in the North-East Atlantic. The effects of the decreasing organic flux, of the carbonate ion concentration and of the bottom water oxygenation on the isotopic composition of the faunas have been investigated. The difference in δ13C between a shallow infaunal and a deep infaunal species (Δδ13C U. peregrina - Globobulimina spp.) shows a good correlation with the organic flux. When the organic flux is low, benthic foraminiferal microhabitats are extended. Therefore, shallow infaunal species and deep infaunal species calcify in geochemically different environments, and show a high Δδ13C. On the contrary, when the organic flux is high, microhabitats are much more compressed and U. peregrina and Globobulimina spp. live in an isotopically similar environment. Their Δδ13C is in that case close to zero. We asses that (Δδ13C U.peregrina - Globobulimina spp. is a promising proxy of palaeoexport flux. Our data show evidence of the so-called "carbonate ion effect", a fractionation effect which tends to increase the foraminiferal δ18O with decreasing [CO3

2-] (i.e. decreasing pH). This effect is however not visible for the δ13C, it is more than compensated by the microhabitat effect that tends to significantly lower the δ13C of deeper infaunal taxa. We also have shown excellent correlations of the difference in δ13C between deep infaunal species (Globobulimina spp. and Melonis barleeanus) and the bottom water Dissolved Inorganic Carbon (Δδ13CFORAM - δ13CDIC) with bottom water oxygenation. We explain this by the fact that with lower bottom water oxygenation, oxygen penetration into the sediment is lower, and the resulting compression of foraminiferal microhabitats lead the deep infaunal taxa to partially integrate a bottom water signal. Therefore, deep infaunal species record a lower pore water δ13C at the depth of oxygen zero in case of higher bottom water oxygenation.

Calcareous nannofossil biostratigraphy and palaeoecology of the Cenomanian-Turonian succession of ODP Leg 207 (Demerara Rise)

Hardas, P. and Mutterlose, J. Ruhr-University Bochum, Bochum, Germany,. petros.hardas@rub.de During ODP Leg 207 at the Demerara Rise a thick black shale succession was drilled, covering the late Albian to late Santonian. We have studied the biostratigraphy and palaeoecology of the Cenomanian-Turonian succession with respect to its content in calcareous nannofossils. The biostratigraphy of the Cenomanian-Turonian boundary interval -where the Oceanic Anoxic Event 2 (OAE2) occurred- has been studied at four sites (1258, 1259, 1260, and 1261); 147 samples have been analyzed. We have identified the following eight calcareous nannofossil bioevents (first occurrences, FOs and last occurrences, LOs): LO of Corollithion kennedyi, FO of Cylindralithus biarcus, LO of Axopodorhabdus albianus and FO of Quadrum gartneri, FO of Quadrum intermedium, FO of Eprolithus octopetalus, FO of Eprolithus eptapetalus, and FO of Eiffellithus eximius. These bioevents have been correlated with the stable carbon isotope curves of Erbacher et al. (2005). The FO of Q. gartneri was observed in the lower part of the δ13Corg excursion, which is earlier than in the sections of Eastbourne, Pueblo and Oued Mellegue, where its FO falls very close to the onset of decreasing δ13C values in the upper part of the excursion interval. Sixty samples from Sites 1258 and 1260 have been analyzed quantitatively. During the δ13Corg excursion calcareous nannofossil assemblages show a reaction. The high fertility indicator

Zeugrhabdotus erectus shows a significant increase of its relative abundance, whilst the oligotrophic species Watznaueria spp. decreases strongly. This indicates enhanced nutrient input during OAE2. The suggested cooler water species Eprolithus floralis decreases, which may indicate warmer surface-water temperatures during this event. The study of the whole early Cenomanian - late Turonian succession (105 samples) reveals a major turnover of nannofossil assemblages in the Middle Cenomanian Event (MCE). Extreme high percentages of the eutrophic species Biscutum constans in the early Cenomanian indicate a mixed water column with high nutrient availability, while after the MCE more stratified water- and oligotrophic conditions seem to prevail. Erbacher, J., Friedrich, O., Wilson, P.A., Birch, H., Mutterlose, J., 2005. Stable organic carbon isotope stratigraphy across Oceanic Anoxic Event 2 of Demerara Rise, western tropical Atlantic. Geochemistry, Geophysics, Geosystems 6, Q06010, DOI 10.1029/2004GC000850.

Benthic foraminiferal assemblages at the continental margin off Costa Rica and Nicaragua

Heinz, P., Ruschmeier, W. and Hemleben, Ch. Institute of Geosciences, Tübingen University, Germany. petra.heinz@uni-tuebingen.de Living (Rose Bengal stained) foraminifera from the continental margin off Costa Rica and Nicaragua were investigated. Assemblages between 7 stations, including mud volcanoes, were compared in terms of abundances, distribution patterns, diversity, and species composition. Additionally, environmental information (organic carbon content in the sediment, particle grain sizes) was considered for comparison. Highest foraminiferal densities were described from the slope off Nicaragua. Lowest foraminiferal records were found at the smooth Cocos plate segment, median values were counted on the southern rough Cocos plate. The lack of juveniles and opportunistic taxa is interpreted as due to the absence of fresh food material. In total, 187 species were observed at seven stations, which all showed high diversity. Foraminiferal communities, containing many Buliminida, point to low oxygen concentrations in the vicinity of fluids. Samples originating from mud volcanoes do not show any outstanding assemblages, indicating that vent influenced sediments were not sampled.

Macroecological significance of coccolith size

Herrmann, S., Weller, A. and Thierstein, H.R. Geological Institute, ETH Zurich, Zurich, Switzerland. sandra.herrmann@erdw.ethz.ch. The few morphological investigations of living coccolithophores and coccoliths in surface sediments have shown multivariate dependencies of size variability of single species or genera. Coccolith size variability of Calcidiscus leptoporus appears correlated to temperature (Quinn et al., 2004), that of Florisphaera profunda to combined light and nutrient maxima in the lower photic zone (Quinn et al., 2005), and size of E. huxleyi to salinity (Bollmann & Herrle, 2007). Given this considerable diversity of apparent controls in today's species and genera the question of interest is whether there are more general macroecological patterns in coccolith sizes. For this a global set of Holocene sediment samples was prepared and analyzed in a scanning electron microscope (SEM). Approximately 300 measurements of the maximum coccolith diameter (D) in each sample were collected. The assemblage means of D were subsequently analyzed for correlation with environmental parameters (e.g. temperature, salinity, etc.) of the photic zone at the sample sites. On a global scale D appears to correlate negatively with temperature and salinity and positively with phosphate, and nitrate contents. The few outlier assemblages in our current data set are subject to ongoing further analyses. Bollmann, J. & Herrle, J.O., 2007. Morphological variation of Emiliania huxleyi and sea surface

salinity. Earth and Planetary Science Letters, 255, 273-288.

Quinn, P.S., Sáez, A.G., Baumann, K.H., Steel, B.A., Sprengel, C. & Medlin, L.K., 2004. Coccolithophorid biodiversity: evidence from the cosmopolitan species Calcidiscus leptoporus. In: Thierstein, H.R. & Young, J.R., 2004. Coccolithophores - from molecular processes to global impact. Springer Verlag.

Quinn, P.S., Cortés, M.Y. & Bollmann, J., 2005. Morphological variation in the deep ocean-dwelling coccolithophore Florisphaera profunda (Haptophyta). European Journal of Phycology, 40, 123-133.

Foraminifera, calcareous nannoplankton and stable isotope (δ18O, δ13C) of the Bryozoan event in the Middle Miocene of the Central Paratethys

Holcová, K. (1) and Zágorsek, K. (2) (1) Institute of Geology and Palaeontology, Charles University of Prague, Faculty of Sciences, Praha 2, Czech Republic, Holcova@natur.cuni.cz (2) National Museum, Praha 1 To improve value of Bryozoa as a palaeoecological indicator, the ancient environmental parameters of the Bryozoan Middle Miocene event were detailed study using Foraminifera, calcareous nannoplankton and oxygen and carbon stable isotope data. Abundant occurrence of Bryozoa in the Middle Miocene of the Central Paratethys was isochronous event which can be correlated with M6 Zone between FO of Orbulina suturalis and LO of Praeorbulina circularis (14.8 - 14.58 Ma). The ecosystems of the Central Paratethys marine basins in this time were generally influenced by the Middle Miocene climatic optimum and the large transgression which covered the Central Paratethys basins by tropical-subtropical waters ((Rögl & Steininger 1983, Rögl 1998, Popov et al. 2004). These events catalyzed expansion of Bryozoa. They settled only narrow shallow-water zone of the basin accompanied by epiphytic (Asterigerinata, Lobatula) and large foraminifers (Amphistgina, Elphidium), rarely also by cibicidoids. Although foraminiferous assemblages show only small palaeoenvironmental variations, Bryozoa species composition vary. Therefore, four bryozoan clusters can be distinguished in shallow water environment. Reteporella - Hornera verrucosa assemblage appeared in high-energy environment, Buffonellaria - Rhynchozoon occurred in warm-water biotopes with sea-grass meadows on carbonate substratum. Smittina - Metrarabdotos assemblage is accompanied by foraminifers indicating influence of cold and/or meteoric water and stabilization of suboxic zone in sediment. Schizomavella tenella – the Schizoporella tetragona assemblage was recorded almost in all shallow water environments, so this cluster probably joint well adaptable species. Only in one locality was distinguished exceptional deeper water Tervia irregularis assemblage, which appeared only in very short time. Popov, S.V., Rögl, F., Rozanov, A.Y., Steininger, F.F., Shcherba, I.G. & Kovác, M., 2004.

Lithological-Palaeogeographic maps of Paratethys. 10 maps Late Eocene to Pliocene. Courier Forschunginstitut Senckenberg, 250, 1-46.

Rögl, F., 1998. Palaeogeographic considerations for Mediterranean and Paratethys seaways (Oligocene to Miocene). Ann.Naturhist.Mus.Wien, 99A, 279-310.

Rögl, F. & Steininger F. F., 1983. Vom Zerfall der Tethys zu Mediterran und Paratethys.-Die neogene Palaeogeographie and Palinspastik des zirkummediterranen Raumes. Ann.Naturhist.Mus.Wien, 85/A, 135-164.

Middle Miocene to Late Pleistocene climate variability in the Indo-Pacific region: Foraminiferal highlights

Holbourn, A. and Kuhnt, W. Institute of Geosciences, Christian-Albrechts-UniversityKiel, Germany. ah@gpi.uni-kiel.de Although the Indo-Pacific is arguably the most important region to unravel tropical climate evolution during the Cenozoic, foraminiferal distribution patterns and geochemical signals are still poorly understood. We present highlights of research projects that focus on three main phases of Neogene climate change: the middle Miocene cryosphere expansion, the "Mid-Pleistocene Revolution" and the last glacial cycles. About 13.9 million years ago, the Earth's climate cooled dramatically after an extended period of relative warmth. We present astronomically-tuned climate proxy records (benthic and planktic stable isotopes, XRF data, benthic foraminiferal census counts) in two continuous sedimentary successions from the northwestern and southwestern Pacific (ODP Sites 1146 and 1237), which shed new light on the middle Miocene climatic transition. Three distinct climate phases are recognized with different imprints of orbital variations into the climatic signals: (1) climate optimum prior to 14.7 Ma characterized by minimum ice volume and prominent 100 kyr variability, (2) long-term cooling from 14.7 to 13.9 Ma, principally driven by obliquity and culminating with rapid cryosphere expansion at the onset of the last and most pronounced δ13C increase, (3) "Icehouse" mode after 13.9 Ma with distinct 100 kyr variability. Our results suggest that eccentricity was a prime pacemaker of middle Miocene climate evolution through the modulation of long-term carbon budgets and that obliquity-paced changes in high-latitude seasonality spurred final entry into the "Icehouse". During the Late Pliocene-Middle Pleistocene more than 50 species of benthic foraminifera ("Stilostomella group") disappeared from the deep sea in the South China Sea as part of the last global extinction in the deep sea. This extinction was characterized by a pulsed decline in abundance and species richness that occurred mostly during glacials, and coincided with increased cooling of the Earth's climate since 2.5 Ma, especially during the Mid-Pleistocene Climate Transition. The detailed pattern of extinctions is correlated to orbitally-tuned timescales in ODP Sites 1143 and 1146. Mid-Pleistocene extinctions appear linked to the more extensive influence of oxygenated deep waters, associated with development of the 100 kyr cycles. The Indonesian Throughflow (ITF) represents a critical component of the modern thermohaline circulation as the only low-latitude meridional passage of intermediate water between the Pacific and Indian Ocean. We used planktonic and benthic foraminiferal multiproxy records to monitor the intensity and vertical profile of the ITF in relation to global and regional climate variability over the last two glacial cycles. XRF Fe and Ti data together with benthic foraminiferal based palaeoproductivity records from the Timor Sea closely track the evolution of the ITF outflow in relation to monsoonal intensity. Our results and recent oceanographic observations indicate that the SE Asian and Australian monsoonal systems strongly modify the intensity and vertical structure of the ITF on several timescales: glacial-interglacial, precessional and ENSO.

French national project FORCLIM : development of a proxy for the palaeohydrology in the North Atlantic

Howa, H.(1), Anschutz, P.(2), Eynaud, F.(2), Jorissen, F.J.(1), Labeyrie, L.(3), Lombard, F.(3), Loncaric, N.(1), Malaizé, B.(2), Michel, E.(3), Mouret, A.(2), Retailleau, S.(1), Schmidt, S.(2) (1) Laboratory of Recent and Fossil Bio-Indicators, UPRES EA 2644, Université d’Angers, Angers

Cedex, France helene.howa@univ-angers.fr

(2) UMR CNRS 5805 Oceanic Environments and Palaeoenvironments (EPOC), Bordeaux University, France

(3) Laboratoire des Sciences du Climat et de l'Environnement, Gif-sur-Yvette, France The ANR Project FORCLIM “Temperature and Salinity of the North Atlantic by geochemical and isotopic analyses of foraminiferal shells” is undertaken within a close collaboration framework of three French laboratories: BIAF, LSCE and EPOC. The final objective of the project is to further improve oceanographic proxies which allow quantification of hydrological changes in the North Atlantic during late Holocene periods of rapid climate change. Such proxies may help to estimate the rate of eventual slow-down of thermohaline circulation in the future. In this context, the project aims to increase resolution of palaeo-estimates based on the stable isotope composition (δ18O/ δ16O and δ13C/ δ12C) and trace element content (Cd/Ca, Zn/Ca, Mg/Ca, Ba/Ca ratios) from planktonic foraminiferal shells. These proxy methods will be improved by calibration using in-situ collected living faunas and strengthened by ecological modelling taking into account the foraminiferal vertical and lateral distribution, and growth seasonality. Five oceanographic cruises (June 2006; April and November 2007; spring and summer 2008) are scheduled in the Bay of Biscay by the R/V “Côte de la Manche” (CNRS-INSU). During the first expedition in June 2006, a sediment trap mooring was deployed at a station located on the northern border of the Plateau des Landes (Bay of Biscay). Two deployed sediment traps will intercept the 24-months record of the seasonal deposition flux of planktonic foraminifera at the water depth of 800m and 1700m. In addition, during each oceanographic cruise, plankton tows will be collected in the upper 700m of the water column at 7 stations across the Plateau des Landes, to get better insight into the vertical distribution of the various species in the water column. Simultaneous measurements of the geochemistry of the water column (temperature, salinity, chlorophyll-a, nutrient content) will help to better understand the ecology of the faunas, and measurements of sea (δ18O/ δ16O and δ13C/ δ12C will be compared to the geochemistry of the captured foraminiferal shells.

Behavior of bathyal benthic foraminifera at sediment-water interface: Long-term in situ observations with planar oxygen optode at Sagami Bay, Japan

Kitazato, H. (1), Oguri, K. (1), Nomaki, H. (1) and Glud, R. N. (2) (1) Institute for Research on Earth Evolution, Japan Agency for Marine-Earth Science and Technology, Yokosuka, Japan, kitazatoh@jamstec.go.jp (2) Marine Biological Laboratory, University of Copenhagen, Helsingor, Denmark Biogeochemical cycles in the oceans have been controlled at sediment-water interface through activities of benthic organisms. Benthic foraminifers that are dominant at sediment-water interface should play important roles for the cycle. However, activities of benthic foraminifera such as metabolism, remineralization rates of organic carbon, movements and others are poorly understood except for shallow water groups. In situ observation devices and facilities are keenly required for understanding nature of deep-sea benthic foraminifera. We have developed high-precision planer optode system that can work at deep-sea floor. Hand-made planer optode film is so sensitive that it can detect the movement of submillimeter-size organisms at sea floor (Oguri et al., 2006). We have deployed the system on the sea floor at 1177m in deep, connecting with underwater cable network system. We have taken series of 3142 oxygen images for continuing 4 days. The results gave us important information about dynamics of sediment-water interface and benthic foraminifera. 1) We have detected dynamic changes in sediment microenvironments at sediment-water interface. Oxygen penetration depth with 5-8 mm thick changed in response to benthic activities such as polychaetes, crustaceans or nematodes. Polychaetes play a role for bio-irrigation with dwelling in tubes. Crustacean species move actively on and in sediment and play a role for bioturbation. Oxygen penetration depths also change in relation to water current.

2) Benthic foraminifera move actively through oxygen-depleted layer below oxygen penetration depth. Benthic foraminifers move very quick through sediment. The speeds sometimes reach at 20 µm/min and are comparable to those of shallow water groups (Kitazato, 1988). 3) Very active nitrogen cycle has detected at Sagami Bay sediments. Some species of benthic foraminifera certainly concentrate nitrate within their cytoplasm. This suggests that deep infaunal benthic foraminifers should take part in nitrogen cycle at sediment-water interface. We believe that benthic foraminifera play important roles in biogeochemical cycles at sea floor, in particular to nitrogen cycles. Kitazato, H., 1988, Locomotion of some benthic Foraminifera in and on sediments. Journal of

Foraminiferal Research, 18, 344-349. Oguri, K., Kitazato, H. and Glud, R.N., 2006, Platinum octaetylporphyrin based planar optodes

combined with an UV-LED excitation light source: an optimal solution for high-resolution O2 imaging in O2 depleted environments. Marine Chemistry, 100_95-107.

Benthic foraminifera in the Nazaré canyon, Portuguese continental margin: influence of sedimentary disturbance on fauna

Koho K.A. (1), Kouwenhoven T.J. (1), de Stigter H.C. (2), van der Zwaan G.J. (1,3) (1) Faculty of Geosciences, Utrecht University, Utrecht, The Netherlands. koho@geo.uu.nl (2) Royal Netherlands Institute for Sea Research (NIOZ), Den Burg Texel, The Netherlands (3) Faculty of Biology, University of Nijmegen, Nijmegen, The Netherlands The total standing stock, species assemblage and vertical distribution of living (rose Bengal stained) benthic foraminifera were investigated along the depth gradient in Nazaré canyon, which is located on the Western Iberian continental margin. Foraminiferal assemblages from the highly disturbed axis of the upper (< 2700 m) and middle canyon (2700-4000 m), experiencing frequent sediment resuspension and gravity flows, were compared with the assemblages from the adjacent low energy terraces and the lower canyon (> 4000 m). In addition, the community changes were investigated in relation to water depth and bio-available carbon. In general, low total standing stocks (TSS) of foraminifera were found in the frequently disturbed upper and middle canyon axis. The highest TSSs were recorded in the upper canyon terrace stations, where fine grained sediment and organic carbon is able to accumulate. One of the upper canyon axis stations was highly dominated by a species of Technitella, making up to 75 % of the TSS. This taxon can be regarded as highly opportunistic, is able to colonise disturbed environments, and tolerates high sedimentation rates, resuspension of surface sediments and fast current speeds. In addition, Technitella spp. appears to thrive under eutrophic conditions. The quiescent terrace stations recorded high abundances of infaunal species, including Melonis barleeanum, Globobulimina spp. and Chilostomella oolina. The occurrence of these species reflects the low pore water oxygen concentrations and high bio-available carbon supply. Several tubular Bathysiphon species were found in the upper canyon terrace stations. Instead, the deepest stations of the lower canyon were dominated by another large agglutinated protozoan, Saccorhiza ramosa. The change in the arborescent/tubular foraminiferal community may reflect the increase in sediment oxygenation with increasing water depth in the canyon, S. ramosa preferring the relatively better oxygenated lower canyon environment due to the ferruginous cement it uses to build its test.

Biogeographic patterns and hotspots of diversity in larger foraminifera through time

Martin R. Langer Institute of Palaeontology, Rheinische Friedrich-Wilhelms Universität, Bonn, Germany martin.langer@uni-bonn.de Larger symbiont-bearing foraminifera are prominent components of tropical and subtropical shallow-water faunal biotas and contribute significantly to the carbonate produced in the world's ocean. We have established global biogeographic databases for Palaeozoic, Upper Cretaceous and modern larger foraminifera and compiled occurrence data to analyze their biogeographic and latitudinal distribution in time and space and to examine shifts and distributional changes that are related to the constellation of the continents and the heat flow of the oceans. Both the Late Palaeozoic (Carboniferous/Permian) and the Late Cretaceous Oceans (Campanian/Maastrichtian) differ markedly from modern oceanographic settings and are primarily constrained by the continental constellation of the past. This affects the global current system, the heat transfer from equator to the poles, the extension of sea surface temperatures (SSTs) along longitudes and latitudes, and ultimately the distribution of tropical and subtropical biotas in the ocean environment. This study indicates that the latitudinal ranges of individual larger foraminiferal taxa can be used to assess the heat transfer regulated by the major ocean current regimes to infer sea surface temperatures (SST). The longitudinal range of taxa is applied as measure for dispersal capabilities as controlled by the prevailing currents and SST patterns. The global biogeographic data sets compiled also allowed us to assess global patterns of diversity of larger foraminifera and to identify hotspots of diversity through time. To analyze causal mechanism regulating both diversity and biogeographic distribution, both Palaeozoic and Upper Cretaceous data set are compared to distributional and diversity data from modern symbiont-bearing foraminifera to assess factors regulating shifts and pathways in the evolution of diversity through time.

Is the benthic Foraminifer Virgulinella fragilis a proxy for oxygen depletion?

Leiter, C. Department for Earth and Environment, München, Germany. c.leiter@gmx.de Living Virgulinella fragilis GRINDEL & COLLEN occurs in the organically rich diatomean oozes of Namibia´s coastal upwelling region. Samples of the cruise M 47 in the year 2000 showed occurrence of empty and bengal rose stained tests of V. fragilis in the fraction > 250 µm. During the cruise M 58 in 2003 some stations of the M 47 with high amount of V. fragilis where resampled to detect variability. The number of stations comprising V. fragilis and their average population density decreased sharply from cruise M 47 to cruise M 58. Here is no correlation obvious. For the question where the species is gone investigations of the finer fraction 150 - 250 µm where made. All these quantifications provided no coherence. Geochemical analyses and sedimentological investigations where made in order to make reasonable these chaotic patterns. The geochemical values cannot be related with the occurrence of V. fragilis. However the detection of living V. fragilis solely in a sediment depth of 9-11 cm might be of importance. Bacterial endobionts and kleptoplasts enable V.fragilis to thrive under microaerophilic, sulfidic conditions (Berard 2003). The detection of stained tests in a depth of 9 -11cm of the M 58 samples rises the question if V. fragilis is following the redox horizon which is due to the higher oxygen amount at the sediment water interface shifting downwards. The fluctuation and irregular anomalies in

temperature, salinity and oxygen concentration are typical of Namibia´s upwelling cells (Altenbach & Struck 2006). Altenbach, A.V., Struck, U., 2006. Some remarks on Namibia´s shelf environments, and a possible

teleconnection to the Hinterland. The changing culture and nature of Namibia: Case studies. Basler Afrika Bibliographien, Basel.

Bernhard, J.M., 2003. Potential Symbionts in Bathyal Foraminifera. Science, 299 861

Foraminiferal and geochemical response to a salinity gradient along a subtidal transect on the Aurray estuary (Brittany, France).

Leorri, E. (1), Jorissen, F. (2), Redois, F (2), Reichart, G.-J. (3), Geslin, E. (2) (1) Facultad de Ciencia y Tecnología, Universidad del País Vasco, Bilbao, Spain. eduleorri@yahoo.es (2) Laboratoire d'Etude des Bio-indicateurs Actuels et Fossiles (BIAF), Université d'Angers,France (3) Department of Earth Sciences, Utrecht University, The Netherlands Foraminifera are known to be good bioindicators of saline intrusion in paralic environments, while microhabitat preferences in these environments have not been extensively studied and usually only the top sediment layer is analyzed. As a part of the European project "Palaeosalt" we have studied benthic foraminiferal microhabitats in the Aurray estuary. Two replicate cores were recovered in the subtidal zone at six sites along the estuary. Salinity and temperature have been constantly monitored in the mouth and in the upper reaches of the estuary. Haynesina germanica, Ammonia tepida, and Eggerella scabra are dominant species everywhere in the estuary. Faunas in the upper estuary are characterized by low species diversity. In the middle reaches of the estuary, species diversity and abundance increase, and smaller foraminifera (<150 microns) are more abundant. At the mouth of the estuary Quinqueloculina seminula and Quinqueloculina bicornis are also dominant. Although the species diversity is similar to the middles reaches, the faunal abundance is lower. In all the cores foraminifera are concentrated in superficial samples. Foraminifera found at deeper levels seem to be result of sediment mixing. There is a gradient of species distribution along and perpendicular to the main channel where dilution of marine water as result of reduced tidal influence upstream seems to be the dominant factor that controls this distribution. We have investigated the relation between the distance to the mouth in the estuary (as a response to variation in salinity) and the isotopic composition of H. germanica and A. tepida. These species have been selected because they live in the upper layer of the sediment and are widely distributed as dominant species in temperate estuaries. The δ13C values show a clear trend, with lighter values in the upper estuary, reflecting the mixing of sea water with isotopically light river water. The δ13C values are significantly lighter in the upper estuary, probably as a result of the important supply of continental organic matter. The δ18O shows a surprising pattern: the lightest values are measured at the mouth of the estuary, where salinity is highest, whereas the inner parts show systematically heavier values.

Multispecies modelling approach to predict foraminiferan growth, ecological niches and shell export to the sea floor

Lombard, F. (1), Michel, E, Labeyrie, L (1) Laboratoire des Sciences du Climat et de l'Environnement/IPSL, CNRS-CEA-UVSQ, Gif/Yvette cedex, France, lombard@lsce.cnrs-gif.fr An ecophysiological model reproducing the growth of different foraminiferan species in function to the environmental parameters has been developed for palaeoceanographic reconstructions. This model estimates growth through the main physiological rates of foraminiferans (nutrition, respiration, symbiotic photosynthesis). The influence of light availability and temperature on respiration,

photosynthesis and growth were calibrated in function of experimental observations newly performed or from literature. Notably, we measured respiration of recently captured foraminifera to better understand the influence of temperature on respiration and photosynthesis. The influence of food concentration, in a Chl a basis was calibrated in regard to field observations. This model is now calibrated for the species Neogloboquadrina pachyderma (dextral and sinistral forms), Neogloboquadrina dutertrei, Globigerina bulloides, Globigerinoides ruber, Globigerinoides sacculifer, Globigerinella siphonifera and Orbulina universa. Using annual mean sea surface temperature (SST), light availability and chl a data from MODIS satellite, the model predict the dominant foraminiferan species over 576 field observations worldwide with efficiency higher than 60%. This model offer large opportunities such as reproduction foraminiferan fluxes observed in sediment traps or increasing the palaeoceanographic information obtained from fossil record.

Planktic foraminiferal content in a mature Agulhas eddy from the SE Atlantic: Any influence on foraminiferal export fluxes?

Loncaric, N. Royal Netherlands Institute for Sea Research (NIOZ), Department of Marine Chemistry and Geology, Den Burg, Texel, The Netherlands, loncaric.neven@univ-angers.fr The Agulhas eddies, large-scale rings of warm salty water, occasionally intrude into the Benguela Current system from the Indian Ocean and progress northwards across the Cape Basin and the Walvis Ridge. This inter-ocean exchange of heat and salt is considered to play a crucial role for the global thermohaline circulation. Yet, the modern faunal composition of mature eddies from the northern Cape Basin was uninvestigated in spite of the global importance of the Agulhas inflow, preventing firm micropalaeontological study of the palaeoceanographic variability of the ocean exchange. This study describes the composition of modern planktic foraminiferal assemblages collected from a mature Agulhas eddy when it entered into the northern Benguela Current system. The effect of the eddy's gradual decay on the foraminiferal communities in the upper water column is specifically examined, using plankton tow and CTD-rosette profiles, obtained within and outside the ring. In addition, exported foraminiferal fluxes beneath the eddy were investigated in order to determine their impact on the accumulation assemblages as recorded in sediment traps moored near the sea floor and in the box-corer core-top sediment. The examined mature eddy "W" was clearly evident on the satellite altimetry images by its elevated surface. It was distinguished from the surrounding ocean by a slightly higher salinity, deeper surface mixed layer and higher planktic foraminiferal content. Similar to planktic foraminiferal fauna in freshly formed eddies from the Agulhas retroflection, species such as Globigerinoides trilobus, Globigerinoides ruber, Orbulina universa, Globigerinella siphonifera and Globorotalia scitula dominated in the ring "W" assemblages. However, Globorotalia menardii, a species previously believed to be characteristic for the Agulhas leakage into the S. Atlantic, was virtually absent in the eddy "W" fauna. Also Globorotaloides hexagona, a species endemic in Indian Ocean waters, was not found in the water column, in the export flux or underlying sediment. The February to July foraminiferal fluxes recorded by sediment traps mirror the February standing stocks from the water column. Here in contrast, the core-top results show dominance of intermediate/cold water species that originate from the seasonal spring bloom. This signal prevails in sediment to the extent that any potential Agulhas eddy signature in the sediment was overprinted.

Response of Globigerina bulloides test size to the 20th century increase in coastal upwelling off NW Africa

Meggers, H., Steinke, S., Baumann, K.-H., Rendle-Bühring, R.H. Research Center Ocean Margins, Universität Bremen, Bremen, Germany. meggers@uni-bremen.de Test size changes in modern planktonic foraminiferal species have been related to ecological factors such as temperature and upwelling intensity. Alkenone sea surface temperature (SST) reconstructions, measured in a sediment core from the heart of the Cape Ghir upwelling system off the Moroccan coast, together with historical wind-stress observations and upwelling indices, show a pronounced upwelling intensification over the last 100 years (McGregor et al., 2007). In this study, we investigated the relationship between the 20th century upwelling intensification off NW Africa and test size variations in the planktonic foraminifera species G. bulloides. Our results reveal a gradual decrease in maximum diameter of G. bulloides over the last 100 years. These findings are consistent with the alkenone SST reconstructions for the same core by McGregor et al. (2007), which show a steady cooling trend of approximately 1.2°C over the last 100 years. Our results imply a direct response of G. bulloides test size to the 20th century increase in coastal upwelling off NW Africa. Therefore we propose that the maximum diameter of G. bulloides is a good indicator to reconstruct variations in upwelling intensity for this region. McGregor, H.V., Dima, M., Fischer, H.W., Mulitza, S. (2007). Rapid 20th-century increase in coastal upwelling off northwest Africa. Science 315, 637-639.

Coccolithophore morphometry and calcification during the sapropel S1 time interval in the Mediterranean Sea

Meier, K.J.S. (1), Beaufort, L. (1), Emeis, K.-C. (2) and Ziveri, P. (3) (1) CEREGE, Europôle Méditerranéen de l'Arbois, Aix en Provence cedex 04, France. meier@cerege.fr (2) Institut fuer Biogeochemie und Meereschemie, Universität Hamburg, Germany (3) Institut de Ciència i Tecnologia Ambientals, Universitat Autonoma, Barcelona, Spain Sapropels are organic-rich sediments that occur periodically in the sedimentary record of the Eastern Mediterranean Sea. Increased productivity and preservation due to increased nutrient supply and bottom water stagnation are the two main factors responsible for the enrichment in organic carbon in the sediments. They are triggered by changes in oceanographical parameters like, e.g. nutrient supply, salinity and temperature, which also directly influence the growth of coccolithophores, their morphology and calcification. By measuring size and weight of individual coccolithophores in a range of sediment cores from the Eastern and Western Mediterranean Sea covering the sapropel S1 time interval, we aim to identify patterns that allow the reconstruction of the processes that led to the formation of the S1 sapropel, and whether they were restricted to the Eastern Mediterranean Sea. Additional geochemical data is used to address possible diagenetic processes that are know to influence coccolithophore morphology and calcification in the modern Eastern Mediterranean Sea.

Coccolithophore assemblages of the Lower Oligocene to Middle Miocene Arroyo Alférez section in northern Colombia

Mejía-Molina, A. (1) Flores, J.-A. (1) ; Torres Torres, V. (2) (1) Universidad de Salamanca, Departamento de Geología, Salamanca, España. alejandra@usal.es; (2) Instituto Colombiano del Petróleo, Santander, Colombia. In this research, the classical bioestratigraphic schemes proposed by Martini (1971) and Bukry (1973, 1975) for the subdivision of Oligocene and Miocene have been chosen, because those was established en detailed sequences of Caribbean Sea. Beside, another events proposed by several authors have been considered. The base of the on-shore Arroyo Alférez sequence studied is localized in the lower Oligocene NP23 (CP18) to Middle Miocene NN5 (CN4), showing a continuous record and an excellent preservation of coccolithophore assemblages. The most representative taxa identified in the section are Cyclicargolithus floridanus, Cyclicargolithus abisectus, Reticulofenestra minuta, Reticulofenestra minutula, Reticulofenestra media and Reticulofenestra pseudoumbilicus. We note also that Helicosphaera spp. was abundant in some intervals, while discoasterids increase towards the top of the section indicating more temperate superficial waters. The Arroyo Alférez on-shore bioestratigraphic scheme constitutes the first calcareous nannoplankton research to construct a biochronologic scheme for the Cenozoic of northern Colombia with application on oil exploration in the offshore areas of the Colombian Caribbean basin and shows a potential palaeoceanographic key for the future correlation with off-shore record. Martini, E., 1971. Standard Tertiary and Quaternary calcareous nannoplankton zonation. In: Farinacci,

A. (Ed.), Proceedings of the II Planktonic Conference. Roma 1970, 2, 739-785. Bukry, D; 1975. Coccolith and silicoflagellate stratigraphy, northwestern Pacific Ocean, Deep Sea

Drilling Project, Leg 32. Initial Reports of the Deep Sea Drilling Project, 32, 677-701. Bukry, D; 1973. Coccolith and silicoflagellate stratigraphy, Tasman Sea and Southern Pacific Ocean,

Deep Sea Drilling Project Leg21. Initial Report Deep Sea Drilling Project, 21, 885ˆ893.

A new separation protocol to investigate the geochemistry of calcareous nannoflora. Application to Meso- Cenozoic pelagic deposits.

Fabrice Minoletti, Michaël Hermoso and Vincent Gressier JE2477 Biominéralisations et Paléoenvironnements, Université Pierre et Marie Curie (Paris 6), PARIS CEDEX 05, France, minolet@ccr.jussieu.fr Despite of the dominance of calcareous nannofossils in pelagic sediments, their specific geochemistry is still underexploited because of their minute dimensions. Geochemical analyses are classically performed on monospecific assemblages of manually-picked foraminifera or on the bulk carbonate, which is dominated by calcareous nannoflora but also contains variable amounts of other calcareous components. In order to study their geochemical signatures, we propose a new protocol enabling the separation of the various micrometric calcareous components of pelagic deposits: calcareous nannofossils, planktic and benthic foraminifera, euhedral crystals, micarb. Particles are separated according to (1) size and (2) resistance to ultrasonication related to their microstructure. (1) The granulometric separation is achieved with sequential filtration steps (from 60µm down to 2µm) which allow the recovery of subsamples homogeneous in size and origin (for example mono- and oligospecific assemblages of coccoliths).

(2) When various components share their dimensions but exhibit distinct microstructures, a strong ultrasonication is implemented. After such a treatment, polycrystalline nannofossils are broken while resistant particles remain unaltered. Both particles can be further separated by filtration. This methodology was applied to various lithologies and palaeoenvironments. Oligospecific nannofossil assemblages from Neogene calcareous oozes lighten the influence of specific vital effects on the coccolith isotopic signatures. For lithified sediments, we present monospecific assemblages of coccoliths and nannoliths from three intervals/lithologies: Cretaceous-Palaeogene transition clays, Early Toarcian Black Shales and Early Cretaceous marls. The comparison between the geochemical evolution of the photic-zone and the diagenetic overprint improves our understanding of critical palaeoceanographical changes during these three periods.

Spatial distribution of benthic foraminifera in the Rhône prodelta: faunal response to organic matter focussing

Mojtahid, M. (1), Jorissen, F. (1), Lansard, B. (2), Fontanier, C. (1), Bombled, B. (2) and Rabouille, C. (2). (1) Laboratory of Recent and Fossil Bio-Indicators, UPRES EA 2644, Université d’Angers, Angers Cedex, France, and Laboratory of Marine Bio-Indicators Study, Ker Chalon, Ile d’Yeu, France meryem.mojtahid@etud.univ-angers.fr (2) Laboratoire des Sciences du Climat et de l'Environnement, Gif-sur-Yvette, France On many continental shelf areas, the combination of high surface water productivity coupled and limited water depth leads to important organic matter deposits on the sea floor. Especially, sediments in coastal zones which represent only 10 % of the total oceanic surface burry about 80% of marine organic matter and accumulate about 90% of fluvial particles. In the Gulf of Lion, the Rhone River is a major source of nutrients and organic matter. This important supply may have a negative effect on the sea floor where the marine food chain may be modified by important eutrophication and hypoxia. The relationship between the composition of benthic foraminiferal faunas and the amounts of organic carbon in the sediment has been the subject of a large number of studies. In general, it has been noticed that very characteristic associations occur in high productivity areas. However, researchers still argue whether these characteristic faunas result from the raised food availability, from the lowered oxygen availability, or from a combination of both factors. In most cases, these two parameters can not be well separated. In our study, three faunal assemblages occur in relation to the organic enrichment gradient in this area. The first assemblage is situated in the immediate vicinity of the river mouth (1.3 % < Corg < 1.9 %); the faunas are characterized by a low density and biodiversity; they are dominated by Nonionella turgida, N. scaphum, Quinqueloculina seminula, Ammonia beccarii f. inflata, in about equal proportions. A second assemblage is situated in the intermediate part of the organic enrichment zone (1.0 % < Corg < 1.3 %) and is characterized by high densities and intermediate biodiversity; faunas are dominated by the species N. scaphum accompanied in lower proportions by Bulimina spp., E. scabra, N. scaphum and V. bradyana. A third assemblage is situated in the outer part of the organic-rich sediments (0.7 % < Corg < 1.0 %). The faunas are characterized by very high densities and a high biodiversity; they are dominated by Cassidulina carinata, Bulimina spp., Eggerella scabra, Nonion scaphum and Valvulineria bradyana, in about equal proportions.

Towards an operational use of benthic foraminifera for organic pollution monitoring in open and enclosed marine environments

Mojtahid, M. (1), Jorissen, F. (1), Pearson, T. (2), Durrieu, J. (3); Galgani, F. (4) (1) Laboratory of Recent and Fossil Bio-Indicators, UPRES EA 2644, Université d’Angers, Angers Cedex, France and Laboratory of Marine Bio-Indicators Study, Ker Chalon, Ile d’Yeu, France meryem.mojtahid@etud.univ-angers.fr (2) (3) TOTAL, Département Environnement Opérations, Pau, FRANCE. (4) IFREMER, Sète, FRANCE. Foraminifera are among the most abundant protists in marine benthic environments. Because of their short life cycles, high biodiversity and specific ecological requirements of individual species, foraminifera react quickly to environmental disturbance, and can be successfully employed as bio-indicators of environmental change, such as those brought about by anthropogenic pollution. In the last decennia, foraminifera have been increasingly used to monitor pollution in a wide range of marine environments, such as intertidal mudflats impacted by oil spillages, harbours affected by heavy metal pollution, or eutrophicated continental shelves. Our best examples of anthropogenic eutrophication are 1) a drill cutting disposal sites at the outer continental shelf off Congo, where we observed a zonation of foraminiferal faunas in the 750 m around the discharge point. In the immediate vicinity of the discharge points (within 70 m), faunas are characterised by low foraminiferal densities. Faunas between 70 m and 250 m of the disposal sites have very high foraminiferal densities, with high percentages of opportunistic taxa such as B. aculeata and B. marginata. Between 250 and 750 m, foraminiferal densities decrease, and the percentages of opportunistic species are lower; 2) a sewage sludge disposal on the sea floor in the Firth of Clyde (Scotland) where we used benthic foraminifera and macrofaunal/meiofaunal assemblages to evaluate the impact. These two communities present a very similar distributional pattern around the disposal site. In its immediate vicinity, both groups show impoverished faunas composed exclusively of species tolerant to strong oxygen depletion. This area is surrounded by an aureole of high density faunas dominated by opportunistic species. Still farther away, faunal density decreases, and equilibrium taxa gradually replace opportunistic species. At about 3 Km of the disposal site, both foraminiferal and macro-/meiofaunal taxa become comparable to those found at the reference station. We used these data to develop a quantitative pollution index, values of which are strongly correlated with the distance to the disposal site. This foraminiferal index offers the possibility to quantify the impact of anthropogenic eutrophication in marine environments, but its validity must be tested in wider range of naturally and anthropogenetically impacted marine environments.

General context of sedimentation and biogeochemistry in the Bay of Biscay (ANR FORCLIM)

Mouret, A., Schmidt, S. and Anschutz, P. Université Bordeaux I, CNRS UMR 5805 (EPOC), Talence Cedex ; France. a.mouret@epoc.u-bordeaux1.fr The main objective of the program ANR-Forclim is to improve significantly the interpretation of fossil foraminifera signals, as a proxy for hydrological changes in the North Atlantic ocean (see for details Howa et al in the same session). A specific task of the FORCLIM project is to characterize the geochemical and sedimentary environment of foraminifera growth in the water column and at the water-sediment interface.

The studied area is the Bay of Biscay, a semi-enclosed basin on the eastern side of the Northern Atlantic Ocean, bathed by homogenous oceanic waters from the North Atlantic Drift. Several rivers in France and Spain (Loire, Charente, Gironde, Adour, Bidassoa, and Ebre) feed the sedimentary basin. The Gironde and Loire Rivers are presently the main sources of fine sediments to the margin (Thomas et al., 1994). We focus on the south-eastern part of the Bay of Biscay on the slope of the Aquitaine margin between the canyons of Capbreton and Cap Ferret. The sediments of this zone are well studied in term of diagenetic processes since ten years. The first Forclim cruise (PECH-1, June 2006) was the first investigation of this system along a depth transect between 150 and 2000 m. Water column and interface sediment samples were collected using CTD-casts and multicorer. Parameters of interest are: nutrient concentration, suspended matter load, radionuclides. Modern sedimentation is assessed on seasonal to century timescales using a multi-tracer approach (234Th, 210Pb, 230Th). Sedimentation intensity (particulate fluxes, bioturbation, sedimentation rate, focusing) presents the expected decreasing trend with depth as expected on margin slopes. However focusing ratios, based on Th-230, support the occurrence of significant horizontal advection of sediments, even at the deepest site. This data set, along with biogeochemical parameters, will help to better understand the relationships between the sedimentary recording, early diagenesis, and the composition of particles in suspension and foraminifera in the water column above the sediment on a continental margin.

Reconstructing middle Miocene Mediterranean palaeocirculation using benthic foraminifera.

Mourik, A.A. (1), Kouwenhoven, T.J. (1), Abels, H.A. (1), Hilgen, F.J. (1), Van der Zwaan, G.J. (1, 2) (1) Department of Earth Sciences, Utrecht University, Utrecht, The Netherlands. mourik@geo.uu.nl (2) Faculty of Biology, University of Nijmegen, The Netherlands An important step in global climate evolution characterizes the middle Miocene and is related to the rapid expansion of the East Antarctic Ice Sheet at ~13.9 Ma. The associated sea level fall may have affected the already narrowed Tethyan seaway connecting the Atlantic, via the Mediterranean, to the Indian Ocean. Narrowing and closure of the eastern part of this seaway will have caused major changes in ocean circulation both on a regional and a global scale. In the Mediterranean the first sapropelitic sediments develop after the climate transition between ~14.2-13.8 Ma. To gain more insight in the effects of climate change and seaway closure on Mediterranean palaeoenvironments and circulation patterns, we have analysed benthic foraminiferal assemblages from the Maltese Islands (Malta, Gozo: central Mediterranean), for an interval covering ~14.9-13.1 Ma. The composite sequence we sampled shows a marked transition from limestones of the Globigerina Limestone Formation to marls and clays of the Blue Clay Formation. The top of the transitional bed between the two Formations has been dated 13.82 Ma and coincides with the middle Miocene global cooling, indicated by the Mi-3b shift in benthic δ18O. This level has recently been selected to define the boundary between the Langhian and Serravallian. Benthic foraminiferal assemblages indicate a faunal turnover between the Globigerina Limestone and the Blue Clay Formations. The Blue Clay fauna is indicative of a relatively stressed and poorly oxygenated environment, which can point to an increase in organic matter supply as well as to a decreased ventilation of the basin. Plankton/benthos (P/B) ratios indicate a sea level lowering between the Globigerina Limestone and Blue Clay Formations that exceeds by far the estimate for a glacio-eustatic fall. Clearly, the P/B ratios are affected by factors other than water depth in this interval.

Experimental dissolution studies on late Mesozoic and Cenozoic foraminiferal assemblages

Nguyen, T.M.P. and Speijer, R P. Department of Geography - Geology, K.U Leuven, Belgium. thiminhphuong.nguyen@student.kuleuven.be Dissolution of calcareous particles in general and foraminifera in particular has long been recognized in fossil assemblages. Although foraminiferal dissolution is qualitatively easily identified in the fossil record, there is surprisingly little knowledge of which taxa suffered most severely from this and to what extent this could have influenced the composition of the entire assemblage. Uncritical use of foraminiferal assemblages, without any assessment of the preservation of the foraminifera, can and will lead to distorted palaeoenvironmental reconstructions. In this PhD project, we are carrying out dissolution experiments on fossil foraminifera selected from successions which record highly variable calcite contents associated with apparent foraminiferal changes (upper Cretaceous and Cenozoic successions) in order to unravel the impact of dissolution on planktic/benthic ratios and on the composition in benthic foraminiferal assemblages. Our preliminary results corroborate results of previous studies, which show that benthic foraminifers are generally more resistant to dissolution than planktic foraminifers, and that the small size fraction dissolves significantly faster than the coarser ones. Consequently, increasing dissolution leads to depressed P/B ratios. Our results also give us an idea about the relative susceptibility of different taxa to dissolution. Based on earlier studies we developed an experimental setup and a method of ranking taxa according to their resistance to dissolution. Among lowermost Eocene benthic taxa studied from Egypt, Lenticulina shows to be the most resistant genus, ranked well before the agglutinated Gaudryina cf. ellisorae - ranked second. This observation is compatible with experience on poorly preserved (presumably strongly dissolved) lower Eocene assemblages from Egypt yielding large numbers trochamminids (non calcareous) and Lenticulina as one of the few calcareous taxa preserved. For the planktic taxa, Acarinina and Morozovella appear equally susceptible to dissolution.

Living benthic foraminifera distribution in the Flensburg Fjord, (western Baltic Sea)

Nikulina, A.(1), Polovodova, I.(1), Schoenfeld, J.(2), and Dullo, W.-Chr. (2) (1) Faculty of Geography and Geoecology, Saint-Petersburg State University, St.-Petersburg; Russia. anikulina@gmail.com (2) Research Unit Palaeoceanography, Leibniz-Institute of Marine Sciences, Kiel, Germany. Living benthic foraminifera were studied in the Flensburg Fjord, Baltic Sea in June 2006. Low population density comparing to the proper Kiel Bight was typical for the fjord excepting the marine part. It was accompanied by high percentage of deformed tests up to 15 % in the innermost fjord and the Gelting Bight. Apparently low values of standing crop regarded to low salinity and relatively high sand content whereas abnormalities of tests - to high levels of trace metals detected in the inner fjord as well as changes in salinity and nutrients distribution. According to environmental conditions four foraminiferal assemblages has been distinguished. The innermost fjord with silt sediments, high levels of nutrients and trace metals was occupied by assemblages of Elphidium incertum with E. excavatum f. excavata. High percentage Ammoni beccarii and E. excavatum f. excavata characterized the central fjord in conditions of reduced salinity and nutrients and medium trace metals content. A. beccarii with E. albiumbilicatum dominated in sandy sediments of the Gelting Bight under reduced salinity and food availability. Predominance of E. excavatum f. excavata and clavata tests was common for the marine environment of the open Flensburg Fjord. Reophax dentaliniformis and Ammotium cassis were found in the central and marine parts of the fjord in amounts less than 5 %; their distribution is seemingly controlled by salinity.

Trophic relationships between phytodetritus, benthic foraminifera, and metazoans: carbon and nitrogen isotopic evidence

Nomaki, H.(1), Ogawa, N. O.(1), Ohkouchi, N.(1), Suga, H. (1), Toyofuku, T.(1), Shimanaga, M.(2), Nakatsuka, T.(3), Kitazato, H. (1) (1)Institute for Research on Earth Evolution, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka, Japan, nomakih@jamstec.go.jp (2) Aitsu Marine Station, Center for Marine Environment Studies, Kumamoto University, Japan (3) Institute of Low Temperature Science, Hokkaido University, Sapporo, Japan We examined the trophic levels of deep-sea benthic foraminifera and metazoans based on stable carbon and nitrogen isotopic compositions of their soft tissue to evaluate the foraminiferal role in deep-sea benthic ecosystems. Living benthic foraminifera and metazoans were collected from two bathyal sites (water depths 750 and 1430 m) and at three moments (April and November 2004/ August 2005) in Sagami Bay, Japan. Both the carbon and nitrogen isotopic compositions significantly differ between foraminiferal species. At the deeper site, δ15N of the benthic foraminifera ranged between 6.7‰ and 11.0‰ (typically 7‰ to 10‰) with inter-species variations. This implies that most benthic foraminifera utilized surface sediments (4.5‰) or particulate organic matter (6.4‰) as their food sources. Many metazoan meiobenthos, in particular polychaetes of meiofaunal size, some harpacticoid copepods, and kinorynchs (examined only in the shallower site) exhibited δ15N heavier than foraminifera, suggesting that they occupy higher trophic levels than the benthic foraminifera. Macro- and mega-benthos (polychaetes, spatangoids, ophiuroids, dentalioids) exhibited δ15N of about 10?16‰, suggesting them to be in trophic levels 1-2 steps higher than metazoan meiofauna and benthic foraminifera. Similar isotopic trends were observed at the shallower site. Combining the isotopic evidences and the observations on gut contents of some metazoan meiofauna, together with previous experimental results, the benthic foraminifera in the bathyal Sagami Bay are considered as a bridge in the energy flow from phytodetritus and sediments to metazoans.

Morphotypes of Globigerinoides ruber (white) in the eastern Mediterranean Sea

Numberger, L.(1), Kucera, M.(1), Hemleben, Ch.(1), Mackensen, A.(2), Schulz, H.(1) Hoffmann, R. (1), Wunderlich M. (1) (1) Institute for Geosciences, University Tübingen, Germany. lea.numberger@uni-tuebingen.de (2) Alfred Wegener Institute for Polar and Marine ResearchBremerhaven, Germany The chemical composition of shells of the planktonic foraminifer Globigerinoides ruber (white) is frequently used to determine past sea surface conditions. Recently, it has been shown that arbitrarily defined morphotypes within this species exhibit different chemical and isotopic signatures. These results imply either that the morphotypes represent cryptic species which possess different ecological preferences or that the species produces predictable morphological aberrations under different ecological conditions. At any rate, the link between shell chemistry and morphology in G. ruber (white) implies an as yet poorly understood but potentially powerful factor that could be used to better interpret palaeoenvironmental data obtained from this species. Here we investigate the presence and distribution through time of morphological types of G. ruber (white) in late Quaternary sediments of the eastern Mediterranean. The reason for carrying out this study is to understand the anomalously high abundance of G. ruber that we found in the MIS 10 glacial sediments (up to 70 %). Following earlier practice, we have defined five arbitrary morphological types within the species, quantified their morphology and determined their relative abundance and stable isotopic composition. An analysis of 19 variables extracted from 562 individuals in four samples shows that the G. ruber morphospace appears continuous and that the recognised morphotypes represent end-members rather than distinct

clusters. On the other hand, we show that the abundance of the morphotypes changes significantly between glacials and interglacials and that the isotopic composition of the types differs. In particular, we note that the anomalously high abundance of G. ruber during the MIS 10 glacial is accompanied by a significantly higher proportion of one of the morphotypes and that two of the morphotypes are morphologically different during MIS 10 compared to MIS 11. Our results indicate that G. ruber (white) populations that proliferated in the eastern Mediterranean during MIS 10 were not identical to those living there during the MIS 11.

SST evolution off NW-Africa during the past 55 kyrs: A multi-proxy approach

Ott, C., Steinke, S., Rendle-Buehring, R.H. Research Center for Ocean Margins (RCOM), Bremen University, Germany. ott@uni-bremen.de In this study, a multi proxy approach involving alkenone-based and Mg/Ca-based (Globigerina bulloides) sea-surface temperature (SST) estimates was used in order to reconstruct the palaeoceanographic conditions of the upwelling area off NW-Africa for the past 55 kyrs. Investigations were carried out on sediment core GeoB8507-3 located ~170 km off the Africa coast in the Northeast Atlantic (19,47° N, 18,09° W, 2411m water depth). The modern-day upwelling zone off NW-Africa is restricted to a coastal band of 50-70 km (Mittelstaedt, 1989). In the region south of ~20°N this upwelling is seasonal occurring during winter and early spring (Wooster et al., 1976). The alkenone-derived SST records show an increase in temperature during the last glacial compared to modern conditions, while SST records based on Mg/Ca ratios show a cooling. These observed opposing trends in the SST records could be related to the overall varying ecological preferences of the different plankton groups. However, these finding could also reflect seasonal differences in their productivity in response to changes in the location and intensity of the upwelling during the last glacial. Mittelstedt, E., 1989. The subsurface circulation along the Morrocan slope. In: Neshiba, S. (Ed.),

Poleward Flows Eastern Ocean Boundaries. Springer, Berlin, pp 96-108. Wooster, W., Bakun, A., McLain, D., 1976. The seasonal upwelling cycle along the eastern boundary

of the North Atlantic. Journal of Marine Research 34, 131-141.

Deposits of thermohaline currents on slopes west of Ireland - a micropalaeontological study

Owen, N.L.1, Toms, L.2, Edwards, R.J.3, and Haughton, P.D.W.2. (1) Department of Geology, College Dublin, Dublin 2, Ireland. owensn@tcd.ie. (2) Marine and Petroleum Geology Research Group, School of Geological Sciences, University College Dublin, Belfield, Dublin 4, Ireland. (3) Department of Geography, Museum Building, Trinity College Dublin, Dublin 2, Ireland. Deposits on the western slope of the Porcupine Bank have been tentatively recorded as contourites. A thorough examination of 170 samples from three cores from this site reveals a coherent lithostratigraphy. Sixty-one different benthic foraminifera taxa were recorded, with twenty-four planktonic species. Interglacial units are dominated by hemipelagic sediments (foraminifera and nannofossil oozes). Glacial sediments are characterized by a high clay content and variable IRD. IRD peaks coincide with a reduced diversity of planktonic foraminifera (consisting primarily of Neogloboquadrina pachyderma (sin.), Globigerina bulloides and Turborotalita quinqueloba) and the appearance of agglutinated tubes in the benthic fauna. Lithostratigraphic correlations are supported or enhanced by comparing % N.pachyderma (sin.). values from each core. Study of the benthic fauna shows a consistent change in assemblage between glacial and interglacial episodes. Estimating flux rates from benthic foram assembages initially suggests that glacial primary productivity (PP) in this

region may have been slightly reduced at this time (75-85g C org. m-2, yr-1) , in comparison with modern PP estimates (90-105g C org. m-2, yr-1). The preliminary results for glacial sediments indicate PP values similar to those observed in the modern Nordic Seas.

Foraminifers and ostracods from the Campanian of the Jezówka quarry, the Miechów Trough, southern Poland: palaeoecological implications

Peryt, D. (1), Witek, A.. (2), Jaskula, I. (2) (1) Institute of Palaeobiology, Polish Academy of Sciences, Warszawa, Poland d.peryt@twarda.pan.pl (2) Department of Ecosystem Stratigraphy, Faculty of Earth Sciences, University of Silesia, Sosnowiec, Poland. Campanian foraminifers and ostracods from the Jezówka quarry in the south-western part of the Miechów Trough, southern Poland, were analyzed. Foraminiferal assemblages in the studied interval are moderately to highly diverse. More than 80 taxa were identified at the generic or specific level. The identified taxa represent 4 suborders: Globigerinina, Textulariina, Lagenina, Rotaliina Representatives of Globigerinina and Rotaliina dominate foraminiferal assemblages. In the studied interval P/B ratio values vary from 40 to 70%; keeled forms make 40 to 70% of planktonic foraminiferal assemblages; H(S), the Shannon-Weaver heterogeneity index is generally high: 2,6-3,2; number of benthic species in the assemblages exceeds 20 and the proportion of agglutinated tests vary from 3 to 25%. Benthic foraminiferal assemblages are dominated by epifaunal morphogroups. Ostracod assemblages are represented by 2 suborders: Platycopida and Podocopida. More than 50 species were identified. Platycopids form 30 to 55% of the assemblages. P/B ratio values and H(S) diversity index indicate outer shelf environment. High contribution of keeled forms to planktonic foraminiferal assemblages, high proportions of epifaunal morphogroups within benthic foraminiferal assemblages and low to moderate contribution of platycopids to the ostracod assemblages indicate mesotrophic to oligotrophic surface waters and aerobic bottom-water conditions.

Recent benthic foraminifera in moderate polluted environment: a case study from Kiel Fjord

Polovodova, I. (1); Nikulina, A. (1); Schoenfeld, J. (2), Belozersky, G. (1) (1) Faculty of Geography and Geoecology, Saint-Petersburg State University, Russia ipolovodova@gmail.com (2) Research Unit Palaeoceanography, IFM-GEOMAR, Kiel; Germany. Kiel fjord is a narrow inlet of the Kiel Bight and undergoes long-term anthropogenic load from intensive shipping, ship-building, ammunition waste and city infrastructure. 90 surficial sediment samples were taken in 2005-2006 and analyzed for foraminifera and sediment geochemistry . Recent benthic foraminiferal community is presented mostly by Ammonia beccarii and subspecies of Elphidium excavatum . A. beccarii and E. excavatum f. excavata substitute each other and we believe that they occupy different ecological niches. In contrary E. incertum and E. albiumbilicatum occur together in area of Friedrichsort isthmus, so called transitional zone between inner and outer Kiel fjords. E. albiumbilicatum seems to be dependent on sand content and shows negative correlation with Corg values. Levels of all trace metals showed the highest values in inner fjord. Cu and Sn exceed background concentrations in 2 and 6 times correspondingly. Copper and zinc have higher levels near the entrance to Kiel Canal (high ship traffic area) and in Dietrichsdorf former shipyards area, whereas enormous high tin levels were observed in central part. All trace metals seem to be bounded with organic matter and show high positive correlations with Corg. Calculated A/E index (A. beccarii vs. E. excavatum) showed high positive correlation with Sn content and Corg.

Tests morphological abnormalities were observed up to 17% in southern and 19% in north-eastern part of the fjord, whereas value typical for natural conditions is 3%. Deformed tests correlate negatively with Corg and SiO2 that confirms the limiting role of food. Negative correlation of E. albiumbilicatum and Sn content in sediments was revealed, that allows the assumption that this species can be used as indicator of tin pollution. Distribution of population density in Kiel fjord is very patchy - the maximum values are in vicinity of Laboe resort, in front of Kiel Canal and in central fjord. Good positive correlations between population density and SiO2, Corg and chlorophyll a were revealed. Population density increased 50 times since 1960s, probably due to relative reduction of human-made pollution after Helsinki Commission started to work and using of antifouling paints, containing toxic substance TBT, stopped in 1990s.

Benthic foraminifera and hypoxic conditions: Results of CTG method in experimental study

Pucci, F. (1,2), Geslin, E. (1), Jorissen, F.J. (1), Morigi, C. (2), Sabbatini, A. (2), Negri, A. (2). (1) University of Angers, France. francypucci@yahoo.it (2) Polytechnic University of Marche, Ancona, Italy In the Adriatic Sea, oxygen-depleted areas have increased in the last century, due to eutrophication. The aim of this work is to determine the response of shallow water benthic foraminifera to oxygen-depleted conditions due to strong anthropogenic impact. We combined an in situ study with laboratory experiments under hypoxic/anoxic conditions, in order to obtain databases on the living benthic foraminifera communities useful to evaluate their use as biological indicators of the coastal equilibrium. Sixteen cores (10 cm long) from the Adriatic Sea, at 35 m water depth were exposed to 1) hypoxic/anoxic conditions (<1 ml O2/l); 2) normal condition (>1 ml O2/l) for 70 days and were analyzed using a highly accurate method (fluorogenic probe Cell Tracker Green CMFDA) to distinguish the living individuals. The experimental results show that the anoxic conditions do not have a direct lethal effect on the majority of benthic foraminifera species which are able to survive for more than 2 months under hypoxic/anoxic conditions. Some taxa (Bulimina spp. and Eggerella scabra) seem to have no preference for a specific microhabitat and their presence until the deepest layers of the sediment denotes their high tolerance with respect to hypoxic/anoxic conditions and the lack of labile organic matter. Some other taxa (Nouria polymorphinoides and Nonionella turgida), migrate to the surface under hypoxic/anoxic conditions, apparently in response to the strong compression of the succession of redox fronts in the superficial layer. The different responses of the benthic foraminifera species to hypoxic events, may be used as a tool in estimating naturally occurring hypoxia.

Distribution of live planktonic foraminifera in the Bay of Biscay during the warm summer of 2006

Retailleau, S. (1), Howa, H. (2), Loncaric, N. (2), Schiebel, R. (3), Terrien, S. (3) (1) Laboratory of Recent and Fossil Bio-Indicators, UPRES EA 2644, Université d’Angers, Angers Cedex, France sophie.retailleau@univ-angers.fr (2) Laboratory of Marine Bio-Indicators Study, Ker Chalon, Ile d’Yeu, France (3) National Oceanography Centre, University of Southampton, UK In the framework of the French national research project "FORCLIM" four plankton tow stations were collected in the Bay of Biscay in June 2006 during an exceptionally warm period (sea surface temperature of 22°C, 2°C above the mean summer temperature). Samples were collected with a WP2 plankton tow (mesh size 100µm) at discrete water depth intervals. Material was soaked in a Rose

Bengal solution in order to discriminate living planktonic foraminifera, rose dyed, from dead ones. The results allow us to deduce the spatial distribution of living planktonic foraminifera as a function of bathymetry and distance from the coast (Station WH. (2000m depth), 131km from the coast; A. (1000m), 79km; B. (550m), 52km; D. (145m), 12km). Living foraminiferal abundance decreases drastically towards the coast from a maximum of 65 specimens/m3 at station WH to 15 specimens/ m3 at station D, and especially between stations A and B where standing stocks decrease by an order of magnitude. Dominant species living in the Bay of Biscay in June 2006 are the taxa commonly found around 45°N : 1) the shallow dwellers (0-100m) Globigerina bulloides, Globigerina quinqueloba, right-coiling Neogloboquadrina pachyderma, and Orbulina universa; and 2) the deep dwellers (below 100m) Globorotalia scitula and Globorotalia inflata. G. scitula shows an atypical vertical distribution pattern. Well known as a deep-dweller, this species lives below chlorophyll maximum at stations WH, A and B but occupies a shallow niche close to the sea surface at the station D, closest to shore. In comparison with surface sediments, we have not found G. ruber and G. trilobus in plankton tow samples, though we expected to find them in this hot surface waters. When do they appear? Is the species remnant or brought in by warm currents? To better understand present and absent foraminifera we need more data. These preliminary results will be enlarged by 5 additional sampling campaigns (April and November 2007, March, April and July 2008) and will be compared to simultaneous measurements of the sea water geochemistry in order to determine the ecology of planktonic foraminifera in the specific environments of this embayment.

Biogeography of coccolithophores in the Equatorial and Southearstern Pacific and establishment of a data-base to develop a MAT

Saavedra-Pellitero, M. (1), Flores, J.A. (1) and Sierro, F.J. (1) (1) Departamento de Geología, Universidad de Salamanca, España, mariemsaavedra@usal.es Surface sediment samples recovered in the Equatorial and Southwestern Pacific were analysed (15ºN to 50ºS and 71ºW to 93ºW). The samples were collected during Génesis III-RR9702A, NEMO-Me0005A and PUCK cruises. Smear slides were prepared to assess the relative abundance of coccolithophore taxa. A minimum of 400 coccoliths per sample were counted under polarized light in petrographic microscope, with a magnification of 1000X. In short, 19 different species (or groups in some cases) were identified, and compared to previous research done (McIntyre and Bé, 1967; Okada and Honjo, 1973¸ Winter, 1994). A total of five biogeographic coccolithophore zones have been established taking into account the abundances of taxa and some significant physical parameters such as temperature and salinity. -Tropical North, characterized by an assemblage mainly composed by Gephyrocapsa oceanica, Florisphaera profunda, "small" Gephyrocapsa and Gephyrocapsa muellerae. -Equatorial, basically dominated by placoliths. -Tropical South, where F. profunda, G. oceanica, "small" Gephyrocapsa, Calcidiscus leptoporus, Emiliania huxleyi and G. muellerae are dominant. Characteristics taxa are Umbilicosphaera sp., Calcisosolenia sp., Oolithotus sp., Syracosphaera sp.p and Rhabdosphaera clavigera. -Subtropical South, with an assemblage dominated by gephyrocapsids, F. profunda, C. leptoporus and Helicosphaera carteri. -Transitional-Subpolar where, "small" Gephyrocapsa is the most abundant taxa, although E. huxleyi, G. muellerae, C. leptoporus, G. oceanica, F. profunda, C. pelagicus (very abundant in this zone) and H. carteri are also well represented. Finally, a quantitative reconstruction of sea surface temperature in ODP Site 1233 (Southeast Pacific) has been made using a Modern Analog Technique (MAT), (Palaeoanalogs 2.0 Therón et al., 2004). McIntyre, A. and Bé, A.W.H., 1967. Modern coccolithophoridae of the Atlantic-I. Placoliths and

Cyrtoliths. Deep-Sea Research, 14, 561-597. Okada, H. and Honjo, S., 1973. The distribution of oceanic coccolithophorids in the Pacific. Deep-Sea

Research, 20, 355-374.

Therón, R., Paillard, D., Cortijo E., Flores, J.A., Vaquero, M., Sierro, F.J. and Waelbroeck, C., 2004. Rapid reconstruction of palaeoenvironmental features using a new multiplatform program. Micropalaeontology, 50, 391-395.

Winter, A., Jordan, R.W. and Roth, P.H., 1994. Biogeography of living coccolithophores in ocean waters. In: Winter A. and Siesser G. (eds) Coccolithophores, Cambridge University Press, Cambridge, 161-178.

Benthic foraminiferal fauna as e utrophication markers in historical time of Adriatic sea

Sabbatini, A. (1), Morigi, C. (1), Pucci, F. (1), Ravaioli, M. (2), Alvisi, F. (2), Matteucci, G. (3) and A. Negri (1) (1) Polytechnic University of Marche, Department of Marine Science, Ancona, Italy, a.sabbatini@univpm.it (2) ISMAR-CNR, Bologna, Italy (3) Istituto di Ricerca Gruppo CSA SpA, Rimini, Italy Benthic foraminifera are one-celled organisms that are widely spread over the worlds' oceans. The high preservation potential of their shells makes them a useful tool to date sediment layers and reconstruct ancient environments. In this case, qualitative and quantitative study of benthic foraminiferal assemblages provide us important information about habitat and life strategies of these protists; palaeoenvironmental reconstruction allows to value environmental and climatic changes occurred over time and to obtain an applicable model to recent systems. The vertical distribution of benthic foraminifera in two sediment cores from the Northern Adriatic Sea has been studied with high resolution. Preparation of micropalaeontological samples followed the standard technique. Quantitative and qualitative analyses of benthic foraminifera have been performed. According to our age model, based on 210Pb and 137Cs analyses, the studied cores span from the past 1000 years to present. Benthic foraminiferal patterns and grain-size analyses indicate a number of substantial environmental changes in the benthic ecosystem. We observed increasing eutrophication in the Northern Adriatic basin occurring from 1900 AD and in particular in the last decades. The local benthic foraminiferal fauna indicates a steady variation of food/oxygen availability and increasing of stress environmental conditions from 1930 onwards. Our results show the cycling replacement of a more stable fauna, consisting of less stress-tolerant epifaunal taxa in combination with sandy substrates by a number of very opportunistic taxa, living in muddy habitats. These taxa are most able to profit from the combination of high food availability and fair oxygen levels. This trend is interpreted as the effect of anthropogenic eutrophication due to intense industrial and agricultural development interested the northern coast of Adriatic basin and the waste water disposal in the Po River as well as to "natural" organic nutrient flux leading to dysoxic, or even anoxic bottom conditions. Foraminifera play an active role in the benthic ecosystem structures and dynamics and their abundance is strongly correlated with organic matter input. Our study confirms high correlation between organic matter flux and distribution of this group over the past. We improve our knowledge on the change from the past "natural" river-marine interaction, to the present-day strongly human-influenced situation.

Molecular analysis of coccolithophores from plankton filter samples

Scherrer, S., Brupbacher, U. and Thierstein, H. R. Geological Institute, ETH Zurich, Zürich, Switzerland. sandra.scherrer@erdw.ethz.ch Genetic information of coccolithophores available today is almost exclusively based on cultured material, and thus restricted to 1) only a few species, and 2) only a few samples of one species. For a better understanding of the inter- and intraspecific genetic variation it is essential to investigate environmental samples and to analyze natural populations.

At the Hawaiian and Bermudan time series stations, in situ plankton samples were collected together with detailed data of environmental conditions. Coccolithophore species abundances at different water depths throughout the year were previously described (Haidar & Thierstein, 2001; Cortés et al., 2001). In the current study we show that genomic DNA of coccolithophores is present on these filters and can be analyzed by specifically adapted PCR-based methods. The genetic diversity on different filters was assessed by isolation of total genomic DNA and subsequent amplification of the nuclear ribosomal internal transcribed spacer (ITS rDNA) with haptophyte specific primers. After cloning of PCR products, clones were sequenced and analyzed. Several haplotypes defined by sequence differences at the ITS region were identified. By isolating all the haplotypes on different filters, genetically distinct clusters can be revealed (including uncultured taxa). Genetic data will be compared to the previously collected morphological data on filters with one predominant geno- or morphotype along with environmental parameters. In addition, our sequence data allows us to track bathymetrical and seasonal variation on coccolithophore abundances. The implications for the ecology and evolution of coccolithophores will be discussed. Aims of this project include assessing the genetic diversity of several coccolithophore species (including uncultured ones), reconstructing ecological patterns and combining genetic with morphological data. Cortés, M.Y., Bollmann, J. & Thierstein, H.R., 2001. Coccolithophore ecology at the HOT station ALOHA, Hawaii. Deep-Sea Research II, 48, 1957-1981. Haidar, A.T. & Thierstein, H.R., 2001. Coccolithophore dynamics off Bermuda. Deep-Sea Research II, 48, 1925-1956.

Planktic foraminiferal ecology of the Arabian Sea

Schiebel, R., School of Ocean and Earth Science, National Oceanography Centre, Southampton, UK rxs@noc.soton.ac.uk The Arabian Sea is a natural laboratory of modern planktic foraminiferal ecology, spanning a wide range of hydrographic and trophic conditions, and is affected by distinctive monsoonal-driven seasonality. On a species level, the abundance of planktic foraminifers is affected by temperature and salinity at a global scale, and by the distribution and quality of food, not nutrients, at a regional scale. However, the combination of both hydrography and food determines the abundance of planktic foraminifers to a significant degree, rather than one or few factors alone. Stratification of the surface water column, i.e. depth and strength of the seasonal pycnocline, possibly combines most of the information which is needed to explain the distribution of planktic foraminifers. In turn, plankic foraminifers could be used to reconstruct the stratification of the ancient oceans. Planktic foraminifera have been used extensively as palaeoceanographic proxies to reconstruct and interpret monsoonal oscillation in the Arabian Sea. This paper aims to present a new perspective on the ecology and spatial and temporal distribution of modern planktic foraminifers of the Arabian Sea, which can serve as a template to explain the presence or absence of planktic foraminiferal species in other regions of the world's oceans, and facilitate more targeted palaeoceanographic reconstruction.

Growth of foraminifers - from carbonate production to proxy incorporation

Schmidt, D.N (1) Kasemann, S. (2) Vance, D. (1) (1) Department of Earth Sciences, University of Bristol, UK d.schmidt@bristol.ac.uk (2) Grant Institute of Earth Science, University of Edinburgh, UK Changes in the size of pelagic carbonate producers influence the amount of material exported to the deep ocean. This size varied considerably over geological time with as yet unquantified implications for pelagic export production. We have determined the changes in foraminiferal carbonate production during the last 100 Myrs in the Atlantic and Indian Ocean from the tropics and the mid latitudes. Throughout most of Cretaceous and Palaeogene, planktic foraminiferal carbonate production is negligible in comparison with coccolithophore carbonate production. The evolution towards modern carbonate production happened in two events: the first at the Eocene/Oligocene boundary, the second around the Miocene/Pliocene boundary with a reversal back to insignificant values in the Mid-Late Miocene. The first step is not paralleled by increases in foraminiferal size, whereas the second one roughly coincides with the time when sizes in foraminiferal assemblages reached ranges larger than they had been at any time before. Size changes reflect growth rate changes in planktic foraminifers due to their triggered reproduction cycles. It has been suggested that these growth rates can influence elemental incorporation of palaeoclimate proxies. To test this effect on the boron isotope ratio of foraminiferal calcite, a proxy for palaeo-pH and hence pCO2, we have performed in-situ boron isotope analysis using secondary ionisation mass spectrometry (SIMS). We tested for the influences of developmental history of the foraminifer, growth rates, depth habitat and symbiont activity on boron incorporation. Average δ11B values of Globorotalia truncatulinoides tests do not vary significantly over a size range from 460 to 670 µm and, hence, δ11B appears to be independent of the final size of the foraminifer and overall growth rates. The change in δ11B from chamber to chamber within a specimen is significant though with lower values in the last chambers of the specimen and higher values in the older part of the test. The highest δ11B and boron concentrations can be found in the earlier chambers, whereas the gametogenetic crust has lower δ11B values. The difference in δ11B is too large to be explained by ecological pH changes during the life of the specimen, i.e. depth migration, alone.

Benthic foraminifera from mud volcanoes in the Gulf of Cadiz: food and oxygen decoupled?

Schönfeld, J., Sommer, S., Pfannkuche, O. and Dullo, W.-Chr. Leibniz-Institute of Marine Sciences IFM-GEOMAR, Kiel, Germany. jschoenfeld@ifm-geomar.de Dissolved oxygen and food availability are dominant factors in controlling the abundance and distribution of benthic organisms. The flux rate of particulate organic matter and its decomposition at the sea bed mainly controls near-bottom and pore water oxygen levels. We investigated this relationship in the Hotspot Ecosystem Research on the Margins of European Seas (HERMES) Project. The depth distribution of living (Rose Bengal stained) benthic foraminifers in near-surface sediments was analysed in short sediment cores from Mercator, Captain Arutyunov and Carlos Ribeiro mud volcanoes in the Gulf of Cadiz at water depths from 350 to 2200 m. The pore water oxygen gradient is affected by near-surface methane oxidation at these sites. The faunal distributions were compared with those from three adjacent locations at the same water depths and under the same surface ocean primary productivity. The pore water oxygen profiles were measured ex situ with microelectrodes at all sites. The benthic foraminiferal population densities decreased parallel to pore water oxygen in near-surface sediments at all sites. The standing stock values in the uppermost centimetre were similar on mud volcanoes and at pelagic settings at a given water depth. However, the assemblages were dominated by endobenthic species on the mud volcanoes whereas tubular arenaceous species and suspension feeders

were frequent at the pelagic sites. Fisher's alpha index displayed consistently lower faunal diversities on the mud volcanoes than at adjacent locations. The individual species' depth distribution on mud volcanoes and at pelagic sites revealed surprisingly different strategies and tolerances. Foraminifers specialised on fresh food or those that prefer a shallow endobenthic habitat, e.g. Melonis barleeanum and Uvigerina peregrina parva, retain their depth distribution in the sediment even at a far lower oxygenation than in ambient settings. Others with an oxygen-gradient related lifestyle or nutrition, i.e. Globobulimina affinis and Cribrostomoides scitulum, adapt their living depth accordingly. These results will help to identify and to better constrain the environmental tolerances of oxygen related indicator species.

Live benthic foraminiferal communities from the oxygen minimum zone of the Pakistan continental margin

Schumacher, S. (1,2), Jorissen, F.J. (1), Dissard, D. (1,2), Larkin, K.E. (3), Gooday, A.J. (3) (1) Laboratory of Recent and Fossil Bio-Indicators, Angers University, Angers Cedex 01, France, and Laboratory of Marine Bio-Indicators Study, Ker Chalon, Ile d’Yeu, France. stefanie.schumacher@awi.de (2) Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany (3) National Oceanography Centre, Southampton, University of Southampton, United Kingdom Live (Rose Bengal stained) benthic foraminiferal communities (hard-shelled species only) from the Pakistan continental margin oxygen minimum zone (OMZ) have been studied in order to determine the relation between faunal composition and the oxygenation of bottom waters. Samples were taken from 133 m to 1870 m water depth during the 2003 intermonsoon (March-May) and monsoon (August-October) seasons. Live foraminiferal densities show a clear maximum in the first half centimetre of the sediment; only few specimens are found down to 4 cm depth. In both seasons the faunas exhibit a clear zonation across the Pakistan margin OMZ. Down to 500 m water depth, Uvigerina ex gr. U. semiornata and Bolivina aff. B. dilatata dominate the assemblages. These taxa are adapted to the very low bottom-water oxygen values (~0.1 ml/l in the OMZ core) and the extremely high input of organic carbon on the upper continental slope. The lower part of the OMZ is characterized by cosmopolitan faunas. Seasonality is not seen in species distribution, but in test size composition. Smaller test sizes dominate the Uvigerina ex gr. U. semiornata and Bolivina aff. B. dilatata fauna during the monsoon season. In the lower part of the OMZ the 63-150 micron fraction is more significant than the larger fraction (> 150 micron). The contrast between faunas typical for the upper part of the OMZ, and cosmopolitan faunas in the lower part of the OMZ, may be explained by a difference in the stability of dysoxic conditions over geological time periods. The core of the OMZ has been characterised by prolonged periods of stable, strongly dysoxic conditions. On the contrary, the lower part of the OMZ has been much more unstable over time, reflecting a higher sensitivity to short-term changes in primary productivity and the intensity of NADW flow. As a consequence well-adapted, shallow infaunal taxa occupy the upper part of the OMZ, whereas in the lower part of the OMZ, cosmopolitan deep infaunal taxa have repeatedly colonised these more intermittent low oxygen environments.

Phylogeography of some selected rotaliids (benthic foraminifera)

Schweizer, M. (1), Pawlowski, J. (2), Geslin, E. (3) and Cedhagen, T. (4) (1) Geologisches Institut, ETHZ, Zürich, Switzerland. magali.schweizer@erdw.ethz.ch (2) Dept. de Zoologie et Biologie animale, Université de Genève, Genève 4; Switzerland. (3) Laboratoire de Géologie, Université d'Angers, Angers cedex 01; France. (4) Biologisk Institut, Aarhus Universitet, Finlandsgade 14, 8200 Århus N; Denmark

Presently, one of the main results obtained by DNA studies on foraminifers is that many morphospecies can be divided into several genetic species. Finding cryptic species seems to be rather systematic in planktic foraminifera (e.g. Kucera & Darling 2002). The genetic diversity is also much higher than expected in allogromiids (Pawlowski et al. 2005). Cryptic speciation also occurs in some benthic calcareous taxa such as Ammonia (Holzmann 2000) and Glabratellidae (Tsuchiya et al. 2003). However, other rotaliids appear more homogeneous genetically; e.g. morphological variation coupled to a low genetic diversity has been observed in Uvigerina peregrina (Schweizer et al. 2005). Therefore, the situation in rotaliids is rather complex, with various cases from cryptic speciation to ecophenotypic variability. Here, we will investigate the phylogeography of some rotaliids with SSU rDNA and, if possible, ITS rDNA, which is more variable. The material includes species belonging to the genera Bolivina, Bulimina, Cibicides, Globobulimina, Nonionella, Rosalina and Uvigerina, which were sampled in different locations (mainly North Atlantic, Skagerrak, Mediterranean and Antarctic). The focus is on the search for cosmopolitan species, the identification of bioprovinces, and the comparison of taxonomies from different locations. Holzmann, M., 2000. Species concept in foraminifera: Ammonia as a case study. Micropalaeontology,

46(suppl. 1), 21-37. Kucera, M., Darling, K. F., 2002. Cryptic species of planktonic foraminifera: their effect on

palaeoceanographic reconstructions. Philosophical Transactions of the Royal Society of London, serie A, 360: 695-718.

Pawlowski, J., Fahrni, J.F., Guiard, J., Conlan, K., Hardecker, J., Habura, A., Bowser, S.S., 2005. Allogromiid foraminifera and gromiids from under the Ross Ice Shelf: morphological and molecular diversity. Polar Biology, 28, 514-522.

Schweizer, M., Pawlowski, J., Duijnstee, I.A.P., Kouwenhoven, T.J., van der Zwaan, G.J., 2005. Molecular phylogeny of the foraminiferal genus Uvigerina based on ribosomal DNA sequences. Marine Micropalaeontology, 57, 51-67.

Tsuchiya, M., Kitazato, H., Pawlowski, J., 2003. Analysis of internal transcribed spacer of ribosomal DNA reveals cryptic speciation in Planoglabratella opercularis. Journal of Foraminiferal Research, 33(4), 285-293.

Factors controlling the distribution of planktonic foraminifera in Red Sea sediments

Siccha, M., Trommer, G., Schulz, H., Hemleben, Ch., Kucera, M. Institute for Geosciences, University Tübingen, Germany. michael.siccha@uni-tuebingen.de With its special geographical and hydrological properties, the Red Sea is a natural laboratory for the reconstruction of past climates. While the southern Red Sea is characterized by Monsoon-controlled inflow of nutrient-rich surface water from the Indian Ocean through the Strait of Bab-el-Mandeb, the northern Red Sea is distinguished by high evaporation rates and low productivity. Most oceanographic factors like temperature and salinity are highly correlated in the surface waters, a phenomenon which poses problems for the interpretation of geochemical proxy data. In an attempt to develop new proxies for oceanographic parameters in the Red Sea, we are investigating the factors that control the distribution of planktonic foraminifera species in surface sediments of the basin. We have generated a new dataset of assemblage counts from 61 multicorer coretop samples and investigated the distribution pattern. Three main patterns emerged: 1) species typical for the waters entering the Red Sea from the Gulf of Aden (Globigerina bulloides, Neoglobuquadrina dutertrei, Globorotalia menardii, Globorotalia ungulata), whose abundances rapidly decrease with increasing distance from the marine connection, 2) Globigerinoides sacculifer, which is found to be representative for the more saline and less warm waters in the northern Red Sea, and 3) Globigerinita glutinata, which increases in relative abundance from north to south and replacing G. sacculifer as the dominant species on the point of transition between northern and southern parts of the Red Sea. Multivariate analyses confirm that the foraminiferal fauna reflects the effect of several parameters, mainly the inflow of Indian Ocean surface water, salinity and temperature. We have attempted to develop faunal transfer functions for

oceanographic variables by several methods. The best results for the prediction of the factors temperature and salinity were achieved by a modification of the revised analogue method, based on smoothing of assemblage data projected onto the basin axis with error margins of 0.42°C and 0.18psu, but similarly good results were also obtained by the Imbrie and Kipp and the modern analogue technique. Reconstructed data of the transfer functions for past time periods are not yet available, the first test with Holocene samples being in progress.

Opportunities and pitfalls of the use of foraminiferal planktic/benthic ratios in palaeodepth reconstructions

Speijer, R.P. and Nguyen, T.M.P. Department of Geography-Geology, K.U.Leuven, Leuven; Belgium, robert.speijer@geo.kuleuven.be The foraminiferal planktic/benthic ratio, often expressed as %P (100% * P/(P+B)), is widely used for palaeodepth estimates. Based on modern P/B-ratio distributions on several continental margins van der Zwaan et al. (1990; Mar. Geol. 95:1-16) developed a formula for calculating palaeodepths from foraminiferal assemblages: Depth = e(3.58732 + 0.03534*%P) including confidence limits. In principle this formula can be a valuable tool to quantify foraminiferal data, especially for reconstructing Quaternary and Neogene palaeodepth and sea-level changes. However, the conversion of P/B ratios into palaeodepths is often applied uncritically. At least four recurrent abuses of the depth model can be observed in published literature: 1) uncritical application to pre-Neogene epicontinental assemblages; 2) neglect of error margins; 3) ignorance of the depth limitations of the method; and 4) lack of quality assessment of the foraminiferal assemblages. 1) Palaeogene and Cretaceous foraminiferal assemblages from Tethyan epicontinental basins often consist of >90%P. Employing the depth model, this would suggest unrealistic palaeodepths in excess of 850 m. Apparently, the relative production of planktic versus benthic tests in epicontintenal basins differed considerably from the present day production, which may learn us something about differences in the functioning of planktic and benthic food webs and bentho-pelagic coupling in deep time. 2) The depth model also provides error margins. Because of the rather large uncertainty of the estimates the model primarily allows for identification of large depth trends (uplift/subsidence), but cannot discern short-term sea-level fluctuations of some tens of meters or less. 3) The mathematics of the depth formula only allows for estimates within the depth range from 36 m (0%P) and 1238 m (100%P). Deeper deposits cannot be assessed in this way. 4) Using P/B ratios as a tool for depth estimates relies on careful consideration of the quality of the foraminiferal assemblage. Foraminiferal assemblages from pre-Quaternary deposits often show signs of dissolution and because of the differential susceptibility of planktics and benthics, the P/B ratios may be strongly offset. This paper will highlight the opportunities and pitfalls of using P/B ratios in palaeoenvironmental studies.

High-resolution and 3-D imaging of foraminifera with X-ray micro-CT

Speijer, R.P.(1), Cnudde, V.(2), Masschaele, B.(3), Foubert, A.(2) and Jacobs, P. (2) (1) Department of Geography-Geology, K.U.Leuven, Belgium, robert.speijer@geo.kuleuven.be (2) Department of Geology and Soil Science, Ghent University, Belgium (3) Department for Subatomic and Radiation Physics, Ghent University, Belgium Shells of foraminifera are three dimensional objects with an internal structure hidden within the shell. These internal structures play an important role in specimen-based research and thus obtaining information of the inside of the foraminiferal shell is crucial for progress in systematic, biometric, and evolutionary studies. Usually sectioning and breaking away the outer wall in combination with SEM

are applied in order to display internal structures in great detail, but these methods are always destructive. In contrast, classical X-ray studies are essentially non-destructive, but generally provide rather blurry images. The recent rise and rapid evolution of high-resolution computed tomography on micron and submicron scale (micro-CT, resp. nano-CT) provides new opportunities for foraminiferal research. It combines the advantage of the non-destructive penetrative power of X-ray analysis with a current magnification of about 1000 times. This resolution for obtaining - in a non-destructive way - morphological or biometrical data from the inside of a foraminifer is unsurpassed by any other method. In this poster we describe the methodology of X-ray micro-CT as it is currently developing at the Centre for X-ray Tomography at Ghent University (UGCT; <http://www.ugct.ugent.be/>www.ugct.ugent.be) and we show the opportunities of virtual sectioning of foraminifera. In principle, this method will also allow for analysis of type specimens (holotypes and paratypes) of species. Our goal is to demonstrate that X-ray micro-CT offers great opportunities in systematic, biometric, and evolutionary research on foraminifera.

Gebel Qreiya (Nile Valley, Egypt) in the Middle Palaeocene: a micropalaeontological and sedimentological reconstruction

Sprong, J. (1), Schulte, P. (2), Speijer, R.P. (1), Steurbaut, E. (3) and Youssef, M. (1) (1) Department of Geography and Geology, K.U.Leuven, Belgium. Jorinde.Sprong@geo.kuleuven.be, (2) Geology and Mineralogy Department, Universität Erlangen-Nürnberg, Germany (3) Royal Belgian Institute of Natural Sciences, Brussel, Belgium (4) Department of Geography and Geology, K.U.Leuven, Belgium In Egypt the homogenous marly deposits of the Dakhla Fm of middle Palaeocene age feature an anomalous bed at the P3a-P3b boundary (Sprong, 2007). This bed is dark purple-brown in colour and laminated, it contains abundant planktic foraminifera, which are often pyritized, it has a lot of fish remains and it is heavily bioturbated. A detailed dataset around the P3a-P3b boundary bed has been analysed for the Qreiya succession, where this bed is very nicely developed. In the studied part of the Qreiya succession the planktic Foraminiferal zones P1c to P4 (Berggren and Pearson, 2005) and Calcareous Nannoplankton zones NTp6 to NTp8C (Varol, 1989) were recognized. Sampling resolution was from 25 cm to every cm in the boundary bed. Both micropalaeontological studies as well as geochemical and sedimentological methods were applied. The first few cm of the dark marl bed contained solely planktic foraminifera, it were the bioturbations present in the dark marl that contained the benthic foraminifera. The benthic assemblage from the bioturbations differed clearly from the middle and middle-outer neritic assemblages below and above the boundary bed. The most easily recognizable benthic species was Neoeponides duwi, a shallow water / opportunistic species. The benthic assemblage showed a sea-level lowering causing deeper water species to disappear from the assemblage. During the start of the transgressive phase the sea floor was anoxic, only planktic foraminifera were able to live. As sea level rose further oxic conditions restored and the benthic realm was firstly re-occupied by shallow water and stress-resistant species. Up section, in the P3b-P4 interval, extensive channelling was observed in the succession. They are believed to be the result of higher bottom water current activity after the sea level change. Berggren W.A. and Pearson P.N., 2005. A revised tropical to subtropical Palaeogene planktonic

foraminiferal zonation. J. of Foraminiferal Research 35: 279-314 Sprong, J., Speijer, R.P. and Steurbaut, E., subm. Biostratigraphy of the Danian/Selandian transition in

the southern Tethys, highlighting the First Appearance of planktic foraminifera Igorina albeari. Submitted to Geologica Acta.

Varol, O., 1989. Palaeocene calcareous nannofossil biostratigraphy. In: S.E. van Heck (Editor), Nannofossils and their applications. Ellis Horwood Ltd., Chichester, pp. 267-310.

Proxy dependence of the timing and pattern of deglacial warming in the tropical South China Sea

Steinke, S. (1), Kienast, M. (2), Groeneveld, J. (1), Chen, M.-T. (3), Rendle-Bühring, R.H. (1) (1) Research Center Ocean Margins, Universität Bremen, Germany. ssteinke@uni-bremen.de (2) Department of Oceanography, Dalhousie University, Halifax, Nova Scotia, Canada (3) Institute of Applied Geosciences, National Taiwan Ocean University, Keelung, Taiwan Sea surface temperatures (SSTs), reconstructed from Globigerinoides ruber Mg/Ca and alkenones (Uk'37) from core MD01-2390 from the tropical South China Sea (SCS) during the last deglaciation reveal a proxy-dependent discrepancy in the timing and pattern of the deglacial warming. Alkenone data suggest that the deglacial warming is punctuated by a decrease in temperature between 17-15 ka BP, corroborating previously published alkenone Uk'37-SST records from the southern SCS. Within uncertainties, this cooling is coeval with Heinrich Event 1 (H 1) in the N Atlantic. In contrast, G. ruber Mg/Ca SST estimates suggest a continuous warming starting around 18 ka BP, without any response to H1. The same contrasting patterns of deglacial surface water warming during deglaciation have been found in the eastern equatorial Pacific (Mix, 2006), implying a common pattern of proxy-dependent difference in recording the deglacial warming of the both sides of the tropical Pacific Ocean. We propose that this discrepancy may be due to differences in seasonality of the planktonic foraminifer G. ruber and alkenone-producing coccolithophores. Mix, A.C., 2006. Running hot and cold in the eastern equatorial Pacific. Quaternary Science Reviews, 25, 1147-1149.

The Last Glacial in the North Atlantic - A High-Resolution Reconstruction using Coccoliths

Stolz, K. (1), Karl-Heinz Baumann (1), Katharina Janke (1), and Patrizia Ziveri (2) (1) FB 5 Geosciences, University of Bremen, Bremen; Germany. kstolz@uni-bremen.de (2) Institut de Ciència i Tecnologia Ambientals, Universitat Autònoma de Barcelona, Bellaterra, Spain. For this project coccoliths are used for the reconstruction of environmental changes in the last Glacial in the North Atlantic Region, therefore sediments from ODP Site 980 (Rockall Plateau, subpolar North Atlantic) have been studied using a high sample resolution. Studies already performed by McManus et al. (2001) clearly show that Site 980 has a high potential to strongly react to climatic and oceanographic changes within the last Interglacial/Glacial cycle. Analyses of δ18O from planktic foraminifera indicate the occurrence of short termed warm events within this generally colder period. The results of the analyses of lithics confirm this showing several phases of high input of probably ice rafted material at the same time. The coccolith assemblage shows drastic changes in numbers throughout the studied glacial record, with total numbers of coccoliths much lower than in the previous Interglacial. They range between maxima of c. 11000 x 106 and minima of c. 200 x 106 coccoliths/ g sediment within the last glacial cycle. Within the major cooling trend of this period, several cooling phases can be pointed out. The assemblage is initially dominated by Emiliania huxleyi. The interstadials are indicated by fluctuations in the occurrence of Calcidiscus leptoporus and the subtropical form Syracosphaera pulchra. Their high abundances denote an enhanced influence of the warm North Atlantic Current (NAC). In the stadials, which are sometimes connected with Heinrich Events, decreases in the coccolith assemblages point to a weakened influence of the NAC, and an enhanced inflow of cold polar waters, and therewith a climatic and ecologic deterioration. Coming investigations on the isotope signal of coccoliths will provide more insight into this story.

McManus, J.F., Oppo, D.W. and Cullen, J.L., 1999. A 0.5 million year record of millennial-scale climate variability in the North Atlantic. Science, 283, 971-975.

The calcareous nannofossil's signature of climate change in the Maastrichtian

Nicolas Thibault and Silvia Gardin UMR CNRS 5143, Université Pierre et Marie Curie, Paris cedex 05, France. nithibau@ccr.jussieu.fr The long-term global cooling that characterizes the Maastrichtian is superimposed by dramatic climate and temperature fluctuations (Barrera & Savin, 1999). This climate evolution is underlined by marine biotic events such as the Inoceramid and Rudist extinctions and significant changes in the planktic foraminiferal assemblages. In order to complete the response of the calcareous plankton community, Maastrichtian nannofossil assemblages were analyzed from different palaeolatitudes and oceanic basins (Tethys, Atlantic, Indian and Tropical Pacific Oceans). Our study reveals a common response of calcareous nannoplankton to global climate change. During the Maastrichtian, two episodes of cooling are underscored by a sensible increase of « cool-water taxa » (A. octoradiata, G. segmentatum, N. frequens and K. magnificus) from chron C32n to C30n. In the uppermost Maastrichtian (upper part of chron C30n), all the sites record : (1) a sudden drop in abundance of « cool-water taxa », (2) the extinction of B. constans and the demise of the fertility taxa, (3) a concomitant acme zone of thermophilic taxon M. murus (chron C29r). This pattern is indicative of maximum warming and lowered productivity of surface waters. The nannofossil climate trend correlates well with the palaeotemperature curve based on fossil plants (Wilf et al., 2003) and with the 187Os/188Os signature of Deccan volcanic activity (Ravizza and Peucker-Ehrenbrink, 2003), thus providing a compelling link between Deccan volcanism and late Maastrichtian warming. The palaeoecological evolution of calcareous nannofossils during the Maastrichtian confirms that the end of the Mesozoic was characterized by a great climatic and environmental instability. Barrera, E. & Savin, S.M., 1999. Evolution of Campanian-Maastrichtian marine climates and oceans.

In: Barrera, E. & Johnson, C.C. (Eds.), Evolution of the Cretaceous Ocean-Climate System, Special Paper Geological Society of America, vol. 332, pp. 245-282. Boulder, CO.

Ravizza, G. & Peucker-Ehrenbrink, B., 2003. Chemostratigraphic Evidence of Deccan Volcanism from the Marine Osmium Isotope Record. Science 302, 1392-1395.

Wilf, P., Johnson, K.R. & Huber, B.T., 2003. Correlated terrestrial and marine evidence fro global climate changes before mass extinction at the Cretaceous-Palaeogene boundary. PNAS 100 (2), 599-604.

Advanced laboratory observations of calcium activity in living foraminifera with the fluorescent Ca indicator Fluo-3 AM.

Toyofuku, T. and Kitazato, H. Research Program for Palaeoenvironment, Institute for Research on Earth Evolution (IFREE), Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka City; Japan. toyofuku@jamstec.go.jp Foraminifera are one of the main producers of marine biogenic carbonate and are widely used to reconstruct palaeoenvironments. However, little is known about the intracellular control on carbonate and trace elemental behavior. In particular, knowledge on calcium ion storage and utilization in foraminifera is of great importance, since it may improve our understanding of the chemical composition of foraminiferal calciumcarbonate and therefore, potentially improve the accuracy of palaeoceanographic interpretations. Recently, fluorescent calcium indicators have been developed that

can be used to observe calcium ion activities within a living foraminiferal cell. In this study, we applied the fluorescent calcium indicator Fluo-3 AM to detect intracellular calcium activities in one species of a shallow water benthic foraminifera, Ammonia beccarii. We show that with this fluorescent calcium indicator it is possible to 1) perform real-time calcium ion observations, and 2) study intracellular calcium ion distribution in foraminifera. We have incubated living foraminiferal specimens under two conditions: in normal, filtrated seawater and in artificial, calcium-free seawater, both to which Fluo-3 AM was added. Fluorescence was seen all over foraminiferal cells in specimens calcifying in normal seawater, while no fluorescence was observed in individuals that were living in calcium-free seawater, though the specimens displayed pseudopodial activity in both media. Therefore, we infer that the observed fluorescence indicates merely the presence of calcium ions. This method may allow detailed, real-time observation of in-vivo calcium activities in foraminifera.

Coccolithophore and planktonic foraminifera export production and seasonality in nearshore sediment traps south of Crete (Eastern Mediterranean)

Triantaphyllou, M.V. (1), Kontakiotis, G. (1), Antonarakou, A. (1), Malinverno, E. (2), Stavrakakis, S. (3), Ziveri, P. (4), Mortyn, P.G. (4), Lykousis, V. (3), Dermitzakis, M.D. (1) (1) Dept. of Hist. Geology-Paleontology, Faculty of Geology & Geoenvironment, University of Athens, Greece, mtriant@geol.uoa.gr (2) Department of Geological Sciences and Geotechnologies, University of Milano-Bicocca, Italy (3) Hellenic Centre for Marine Research, Inst. of Oceanography, Anavyssos, Greece (4) ICTA Autonomous University of Barcelona, Bellaterra; Spain Previous studies have shown that, in eastern Mediterranean, coccolithophores are the major contributors to biogenic particle export production and flux. Within the present work we analysed coccolithophore and planktonic foraminifera-related fluxes in order to assess their contribution to the sediment flux at the south-western margin of Crete (eastern Mediterranean). Six sediment trap moorings were deployed from June 2005 to May 2006, at various locations and different distance from the coastline. Coccolithophores export production and flux shows a strong seasonality at all investigated stations: fluxes are highest (up to 106 coccosphere, 109 coccoliths m2/day) during the summer months, i.e. from June to August, and decrease during winter, although peak flux can develop in December-January at some locations. The assemblage is characterized throughout the year by the cosmopolitan Emiliania huxleyi, followed by Algyrosphaera robusta, which is commonly found at middle to high depth within the photic zone. Among the minor species, the most significant are those which typically thrive in surface waters, such as Syracosphaera spp., Helicosphaera carteri, Rhabdosphaera clavigera stylifera and different species of holococcolithophorids, with minor contribution of Discosphaera tubifera, Umbilicosphaera sibogae, Pontosphaera spp. and Coronosphaera spp. Compared to similar environments in the eastern Mediterranean, A. robusta makes a significant contribution among the deep species, while other species that usually dominate the deep photic zone, i.e. Florosphaera profunda and Gladiolithus flabellatus, show very low flux in this area. Planktonic foraminifera are present throughout the time interval considered in the present study. The planktonic foraminiferal flux data reveal two periods of maximum concentration. The total flux of forams is expressed as the number of forams x m-2 x days -1. The main-relative peak occur during mid December - mid January (2,43x103 forams x m2/day) and the second one during July-August. Among the detected species juvenile forms dominate all the samples. Furthermore, Globigerinella siphonifera and Turborotalita quinqueloba are important assemblage components during the whole period. Minor contributions are recovered for the oligotrophic species Globigerinoides ruber (white and pink variety), Globigerinita glutinata, Globigerina bulloides and Neogloboquadrina pachyderma.

Ecological and biological perspectives on a molecular phylogenetic lineage of Planoglabratella opercularis (d'Orbigny)

Masashi Tsuchiya and Hiroshi Kitazato Institute for Research on Earth Evolution (IFREE), Research Program for Palaeoenvironment, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka, Japan. tsuchiyam@jamstec.go.jp Recently, the accumulation of nucleotide sequence data has made possible molecular phylogenetic analyses of various foraminiferal species. However, the ecological and biological meanings of phylogenetic lineages are not yet clearly understood. We comprehensively studied the life cycle, morphology and breeding experiments of the rocky shore benthic foraminifer Planoglabratella opercularis and conducted molecular phylogenetic analyses based on internal transcribed spacers (ITSs) of ribosomal DNA to clarify the phylogenetic relationships among local populations and their formation mechanisms. We then considered these relationships in light of the breeding and morphological characteristics of this species. The phylogenetic analyses suggested that two ITS genotypes, A and B, exist in P. opercularis. Although genotype A is present over a broad geographical range along the coasts of Japan, small subunit and large subunit data show almost identical sequences. In contrast, genotype B has a limited distribution. The nucleotide sequence and morphology of genotype B populations are intermediate between those of P. opercularis genotype A populations and those of the closely related species P. nakamurai. Thus, genotype B populations may reflect an evolutionary relationship such as interspecific hybridization. The widely distributed genotype A populations display divergence within ITS1 sequences among their distributional areas, with a genetic cline that is related to geographic distance. At least three ITS1 subtypes exist, and genetic divergence was particularly high between the two Pacific subtypes (A-1 and A-2) and a Japan Sea subtype (A-3), suggesting that local genetic populations of ITS1 subtypes are breeding populations of a ring species. Estimation of branching periods suggested that genetic differentiation of local populations may have occurred as a result of the formation of the Japanese Islands. Ecological factors, in particular the low dispersal abilities of both adults and gametes of this species because of its plastogamic sexual reproduction, would facilitate genetic differentiation. The Japanese Islands probably acted as a barrier preventing genetic exchange, because genetic differentiation occurred after the Pacific populations became separated from the Japan Sea population. The Japan Sea became geographically isolated from surrounding seas during the late Cenozoic, with the result that genetic differences may have accumulated particularly within the Japan Sea population.

Evolutionary insight into theoretical and functional morphology of foraminifera

Tyszka, J. (1) and Topa, P. (2) (1) Institute of Geological Sciences, Polish Academy of Sciences, Cracow Research Centre, Kraków, POLAND. ndtyszka@cyf-kr.edu.pl (2) Institute of Computer Sciences, AGH University of Science and Technology, Kraków, POLAND. Theoretical morphology includes two conceptual areas focused on morphology of organisms, including the simulation of organic morphogenesis and the analysis of the possible spectrum of organic forms via morphospace construction. Both areas can be used to generate hypotheses testing functional or adaptive aspects of organic form. Our studies explore emergence of foraminiferal test patterns based on simulation of ontogenetic test growth. We are aware that a test form is directly linked to an overall foraminiferal organism therefore simulation of tests separated from the cell itself strongly simplifies reality. Previous models referred to fixed reference axes and neglected apertures.

We have proposed a new approach in foraminiferal modeling applying a moving reference system referred to apertures, which are introduced based on minimization of the local communication path. Apertures are therefore assumed to play an essential role in foraminiferal morphogenesis and in almost all life functions. The resulted spectrum of simple theoretical morphologies covers nearly all real polythalamous foraminiferal tests. That raises a fundamental question how far shell patterns are subjected to natural selection. It is likely that evolution of small simple foraminifera may choose from an enormous variety of shell shapes that have similar adaptive values. The classical view considers gradual evolution of foraminiferal morphologies. Nevertheless, the theoretical morphospace reveals regions of the morphospace that include similar shell morphologies. These specific fields in the morphospace, called morphophases, are separated from each other by morphophase transitions, which involve sharp or gradual changes in morphology controlled by changes of the model parameters. Evolutionary consequences are essential supposing that gradual genetic changes may sometimes generate abrupt morphologic modifications. The presented model and its resulted morphospace include morphologies resembling small foraminifers classified to Textulariida and Rotaliida. Both groups use the same rules to create similar morphologies. The classical taxonomy based on the wall composition keeps them aside. Molecular biology proves both groups to be closely related, in contrast to tubular foraminifers that employ a very different morphogenetic model. This research was sponsored by the Polish Science Ministry (grant nr 3 PO4D 048 24). See eForams VirtuaLab for further details and references: http://eforams.icsr.agh.edu.pl/index.php/VirtuaLab

Changes in SE Atlantic watermass distribution as reflected by deep-dwelling globorotalids during the Mid-Late Pleistocene.

Ufkes, E. (1), Schneider, R.R. (2), Jansen, J.H.F. (3) and Kroon, D. (1, 4) (1) Dep. of Palaeoclimatology & Geomorphology, Vrije Universiteit, Amsterdam, the Netherlands els.ufkes@falw.vu.nl (2) Institute for Geosciences, Christian Albrechts University, Kiel, Germany (3) Royal Netherlands Institute for Sea Research, Den Burg, the Netherlands (4) School of Geosciences, Grant Institute, Edinburgh, Scotland, UK This study shows changes in (sub)surface watermass distribution in the SE Atlantic during the last 1.1 Ma. We have used the composition of planktonic foraminiferal assemblages in core T89-40 from the Walvis Ridge to reveal the main watermass shifts in relation to Milankovitch rhythms. Today, the region is influenced by the cold water of the Benguela coastal upwelling system. In addition, the area is influenced by warm waters from the subtropical gyre in the West, and, to a lesser extent, by tropical waters from beyond the Angola-Benguela Front in the North. Only sporadically warm Indian Ocean enters the basin from the south. Principal Component Analysis reveals 4 principal components of which the first reflects the intensity of the gyre system strongly modulated by precession. The second warm-water component is dominated by Globorotalia crassaformis and Globigerinoides ruber white, pointing to the influence of low-oxygenated, saline warm waters as found north of the Angola-Benguela Front. The other components reflect the intensity of the coastal upwelling system. We also found that variations in the deep-dwelling species Globorotalia truncatulinoides as well as G. crassaformis reflect changes in deeper water column. We interpret our results to reflect major changes in biogeography and/or adaptation to different environments during the Mid-Pleistocene. A period during which deep winter mixing may have been reduced due to a more southern position of the ITCZ and/or weakened zonal winds resulting in a recirculation of (sub)surface waters in the S. Atlantic as reflected by a regional near-absence of sinistral-coiled G. truncatulinoides and presence of northern input of warm (sub)surface waters species. During the mid-Brunhes the S. Atlantic circulation system reaches its "late Pleistocene state": warm water input from the North strongly diminished and only sporadically occurred during periods of strong southward frontal shifts.

Isotopic gradients at the exit of the Indonesian Archipelago : influence of Indonesian and Australian monsoons

Vénec-Peyré, M.T. (1), Bassinot, F. (2), Moreno, E. (1), Baudin, F. (3) (1) UMR5143 (MNHN-CNRS-UPMC), Département Histoire de la Terre, Muséum National d'Histoire Naturelle, Paris, France, venec@mnhn.fr (2) Laboratoire des Sciences du Climat et de l'Environnement, Domaine du CNRS, Gif-sur-Yvette, France. (3) Département de Géologie Sédimentaire, Université Pierre et Marie Curie, UMR 7072, Paris cedex 05, France The Timor Sea, located between the Indonesian Archipelago and Australia, is the main exit of the Indonesian Throughflow that brings upper thermocline water from the Pacific to the Indian Ocean (surface return branch of the Great Conveyor Belt). It is also located at a key location between the Indonesian monsoon system, to the North, and the Australian monsoon system, to the South. Sea surface δ18O gradient at the exit of the Timor Sea during the last two climatic cycles has been reconstructed using a set of giant piston-cores collected along a N-S transect during IMAGES cruises IV and VII of the R/V Marion Dufresne. The δ18O measurements were performed on the shallow-dwelling planktonic foraminifera Globigerinoides ruber. Oxygen isotopic data indicate that during interglacial periods, no clear surface gradient existed at the exit of the Timor Sea, with the three cores recording roughly the same δ18O values. During glacial periods (MIS 2, MIS = 4 and MIS 6), however, a strong S-N gradient developed at the exit of the Timor Sea. During these periods, the southernmost core (MD01-2378; Holbourn et al, 2005) always shows the lightest δ18O values, the northernmost core (MD98-2165; Levi, 2004), located west of Timor, showing the heaviest values= , and Core MD98-2166, located in between them, showing δ18O values that oscillated between the North and South end-members. Core MD01-2378, at the centre of the Timor Sea, is located within the main pathway of the ITF and is more susceptible to have always recorded surface waters that had travelled across the Indonesian archipelago. But it is also the closest core to Australia among the three. There are, therefore, two possible explanations for our observations: 1/ during glacial times, increased precipitations occurred along the ITF pathway within the Indonesian archipelago in response to stronger Indonesian summer monsoon related to increased land masses exposure; 2/ during glacial times, the southernmost core within the Timor Sea has recorded increased monsoon-related runoff from Australia. We will discuss these two possibilities.

Murrayinella murrayi (Heron-Allen & Earland) and Schackoinella globosa (Millett): morphology, taxonomy and inferred ecology.

Donata Violanti(1), Romana Melis(2) & Selene Porrera (3) (1) Department of Earth Sciences, University of Torino, Italy, donata.violanti@unito.it (2) Department of Geological, Environmental and Marine Science - University of Trieste, Italy (3) Department of Earth Sciences, University of Torino, Italy Murrayinella murrayi (Heron-Allen & Earland) and Schackoinella globosa (Millett) are two small (maximum diameter about 110-180 µm) benthic foraminifers, mainly observed in coastal Indo-Pacific waters (Loeblich & Tappan, 1994). They are common in the inner neritic assemblages of Phetchaburi (Thailand Gulf) (Melis & Violanti, 2006), and are also present in pelitic bottoms of the Khao Lak coastal area (Southwestern Thailand, Andaman Sea), affected by the December 26, 2004 tsunami. The two taxa are very similar, poorly described, reported in literature under different generic names and also the family attribution of both is controversial. Both species have a perforate wall, trochospirally coiled tests with few globose to subangular chambers and a thickly tuberculate to spinose umbilical area. In order to define unambiguous criteria for the separation of the two taxa, a

detailed morphological study has been carried out on well preserved tests, selected from Phetchaburi and Khao Lak assemblages. Quantitative analyses evidenced a different areal distribution of two specie in the Phetchaburi coastal area. M. murrayi is more frequent within the shallowest northern and central bottoms, near river mouths and it appears to be tolerant of salinity variability. Instead, S. globosa characterizes the southern and deeper sites, is less affected by fluvial run-off, and reaches its highest frequencies in diatoms-rich assemblages. This association and the morphology of the umbilical area suggest a herbivorous diet for S. globosa, in comparison with other species, which crack diatom frustules on umbilical tubercles (Austin et al., 2005). Studies in progress on the Khao Lak area, in normal marine waters, are supporting the ecologic interpretations of the two taxa made on the Phetchaburi assemblages. Austin, H.A., Austin, W.E.N. & Paterson D.M., 2005. Extracellular cracking and content removal of

the benthic diatom Pleurosigma angulatum (Quekett) by the benthic foraminifera Haynesina germanica (Ehrenberg). Marine Micropalaeontology, 57, 68-73.

Loeblich, A.R., & Tappan, H., 1994. Foraminifera of the Sahul shelf and Timor Sea: Cushman Foundation Special Publication, 31, 1-661.

Melis, R. & Violanti, D., 2006. Foraminiferal biodiversity and Holocene evolution of the Phetchaburi coastal area (Thailand Gulf). Marine Micropalaeontology, 61, 94-115.

Foram picker: towards automated classification and picking of foraminifera

Weller, A.F. (1), Bartoli, G. (1), Schiebel, R. (2), Corcoran, J. (3) and Thierstein, H.R. (1) (1) Geological Institute, Department of Earth Sciences, ETH Zurich, Zurich, Switzerland. weller@erdw.ethz.ch (2) School of Ocean & Earth Science, University of Southampton, National Oceanography Centre, Southampton, UK (3) The University of Queensland Social Research Centre (UQSRC), University of Queensland, Brisbane, Qld 4072, Australia One future development in micropalaeontology is the conception of an automated foraminifera (foram) classification and picking system. Such a system could consist of a mechanical robotic arm that will locate and pick individual forams from a sample tray and present them to a camera to take images of their umbilical, spiral and lateral sides as these are necessary for "classic" species-determination. Several image features will then be measured from each test-view, which will be used for in-line artificial neural network (ANN) classification. The classified foram will then be deposited in a pre-determined sample container. Emphasis of this presentation will be on the technical concepts, with some preliminary findings also presented. The image dataset used to develop the software will comprise ~600 forams from high and low latitudes with ~40 specimens geographically representative of ~15 selected "most common" species. To this end, a broad, generic image feature measurement routine (including both morphological and textural features) has been developed within the Java-based, public domain imaging software, ImageJ (<http://rsb.info.nih.gov/ij/>http://rsb.info.nih.gov/ij/). >90 image features (e.g. area, circularity, gray value distributions, Fourier shape descriptors, etc.) are measured, including some that do not yet appear necessary, but may actually prove useful after statistical testing of them. Moreover, some features may be particularly useful for determining differences and crossover between images of foram morphotypes. There are several advantages to automated foram classification and picking. Along with freeing the worker from routine microscopy tasks and providing the potential for continuous operation, they may ultimately be coupled with transfer functions (e.g. for automated sea surface temperature reconstructions). The fine determination of subtle differences between foram specimen images could also be helpful in distinguishing genetically distinct but morphologically close individuals. Foreseen problems to overcome include the automatic focusing on individuals and the influence of images of dissolved or broken forams on the ANN.

Stable oxygen isotopes of Thoracosphaera heimii (Dinophyceae) in relationship to temperature; a culture experiment

Zonneveld, K.A.F. (1) , Mackensen, A. (2), Baumann, K.-H. (1) (1) FB 5-Geowissenschaften, Universität Bremen, Germany. zonnev@uni-bremen.de (2) Alfred Wegener Institute für Polar und Meeresforschung, Bremerhaven, Germany To establish a relationship between temperature and the stable oxygen isotopic composition (δ18O) of vegetative cysts of the photosynthetic calcareous dinoflagellate cyst Thoracosphaera heimii, two unicellular cultures of T. heimii have been cultured under different temperatures by using a temperature gradient box. There is a clear relationship between temperature variance and the isotopic composition of T. heimii cysts according to the relationship: T (°C) = -6.827 (δ18Oc - δ18Ow) - 3.906 (R= 0.921), with c = calcite and w = water. Within this paper we are the first to discuss the possible vital effects that might cause an offset between the temperature-isotope relationship found for T. heimii calcite and that of equilibrium inorganic calcite precipitation. No indication for strong kinetic effects as result of fast calcite precipitation can be found. We observed a positive relationship between δ18Oc - δ18Ow and ambient medium water pH. We speculate that this might be the result of the presence of external carbonate anhydrase, which is common in photosynthetic dinoflagellates. The efficiency of this enzyme increases rapidly between pH 7.5 to 9, which could result in an increase in CO2 uptake relative to HCO3

- with increasing pH. We furthermore discuss the possibility of T. heimii using respirative carbon as least as part of its carbon source for calcite precipitation, which can be based on the light values of δ18Oc - δ18Ow and δ13Cc - δ13CDIC (DIC = dissolved inorganic carbon) found in this and previous studies on the isotopic composition of calcareous dinoflagellates. The results of this study as well as the broad geographic distribution of T. heimii, its stable position within the water column, its presence in the geological record since the Late Cretaceous and its resistance against dissolution compared to other plankton groups underlines the potential for a wide usability of the oxygen isotope composition of T. heimii as palaeotemperature proxy for the deeper parts of the photic zone.