“the ecology of inland waters”...ecology in europe. it was perceived (by terrestrial and marine...

www.britishcouncil.es www.csic.eswww.britishcouncil.es www.csic.es

ScienceCOORDINATORS:

Brian MossUniversity of LiverpooL

andy J. Green estación BioLógica de doñana (seviLLa)

“The ecology of inland waters”

EsTación Biológica dE doñana (HuElva), 13-17 ocToBEr 2013

British CouncilEducation and Society

Paseo del General Martínez Campos, 3128010 Madrid. Spain

CSICConsejo Superior de Investigaciones CientíficasVicepresidencia de Relaciones Internacionales

Calle Serrano, 11728006 Madrid. Spain

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THE ECOLOGY OF INLAND WATERS

Opening DoorsScientific workshops for young researchers

Doñana, (Huelva) Spain, 13 - 17 October 2013

1. Introduction 3

2. Presentation 3

3. List of participants 4

4. Programme 5

5. Summary of discussions 8

6. Abstracts 10

7. Evaluation questionnaire 27

8. General comments 31

9. Acknowledgements 31

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Opening DoorsDoñana, (Huelva) Spain, 13 - 17 October 2013

3

INTRODUCTION

TheBritishCouncil inSpain, incollaborationwith theSpanishNationalResearchCouncil (CSIC) isorganisingaseriesofscientificworkshopstoprovideopportunitiesforyoungresearchersfromtheUKandSpaintomeetface-to-facefortheexchangeofideas,knowledgeandinformationonprioritytopicsandtoexplorefutureareasofresearchandcollaboration.

Thisworkshopon“TheEcologyofInlandWaters”wastheeleventhintheseries.

PRESENTATION

Theworkshopprogrammeincluded10key lecturesof30minutes in lengthand20presentationsof15minutesbyatotalof30researchersinthefieldprecededbyashortwelcomeintroductionbyBritishCouncilandCSICrepresentatives.

Opportunities fordialoguewereprovidedat theendofeachsession.Theworkshop finishedwithgeneralimpressionsonthestateofthesubjectareaandfundingopportunitiesandquestionsaboutwhere is freshwaterecologygoing,whatcollaborationsmightbe interesting,whatmakesagoodproposalandwheremightyougetitfunded.

TheworkshopwascoordinatedbyEmeritusProfessorBrianMossandProfessorAndyJ.Green.

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Carles Alcaraz, IRTA, Sant Carles de la Ràpita, [email protected]

Mireia Bartrons, University of Wisconsin-Madison/Universitat de Vic, [email protected]

Susana Bernal, Centro de Estudios Avanzados de Blanes (CEAB-CSIC), Girona [email protected]

Nùria Bonada, Universitat de Barcelona, Barcelona [email protected]

Jordi Catalan, Centre de Recerca Ecològica i Aplicacions Forestals (CREAF), Barcelona [email protected]

Isabelle Durance, Cardiff University, Cardiff [email protected]

Hugh Feeley, Cardiff University, Cardiff [email protected]

Ana Filipa Filipe, Centro de Investigação em Biodiversidade e Recursos Genéticos (CIBIO), Universidad do Porto, Porto [email protected]

Margarita Florencio, Universidade dos Açores, Terceira [email protected]

Belinda Gallardo, University of Cambridge, Cambridge [email protected]

Emili García-Berthou, Universitat de Girona, Girona [email protected]

Eduardo García-Roger, Universitat de València, València [email protected]

Andy Green, Estación Biológica de Doñana-CSIC, Sevilla [email protected]

Jonathan Grey, Queen Mary London, London [email protected]

Cayetano Gutiérrez, Universidad de Murcia, Murcia [email protected]

Christopher Hassall, University of Leeds, Leeds [email protected]

Erika Hogan, Loughborough University, Loughborough [email protected]

Gareth Jenkins, Queen Mary University of London, London [email protected]

Aitor Larrañaga, Universidad del País Vasco, Bilbao [email protected]

Alan Law, University of Stirling, Stirling [email protected]

Christophe Lejeusne, Estación Biológica de Doñana-CSIC, Sevilla [email protected]

Stephen Maberly, Centre for Ecology and Hydrology, Lancaster [email protected]

Eleanor Mackay, Centre for Ecology & Hydrology, Lancaster, [email protected]

Kit Magellan, Universitat de Girona, Girona [email protected]

Brian Moss, University of Liverpool, Liverpool [email protected]

Daniel Perkins, Imperial College London, Ascot [email protected]

Isabel Reche, Universidad de Granada, Granada [email protected]

Marta Sánchez, Estación Biológica de Doñana-CSIC, Sevilla [email protected]

Nigel Willby, University of Stirling, Stirling [email protected]

Kevin Wood, Bournemouth University, Bournemouth, [email protected]

LIST OF PARTICIPANTS

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PROGRAMME

SUNDAY 13TH OCTOBER

20:00: Welcome drinks and informal welcome dinner at the Palacio de Doñana

MONDAY 14TH OCTOBER

9.30 Welcome by British Council and CSIC representatives

Session 1: (Chair, Nùria Bonada)

9:50 Introduction, Brian Moss, Freshwaterresearch:keyandglobalorgoingnowhere?

10:20 Andy Green, Freshwaterbirdsasmajorplayersontheaquaticstage

10.50 Kevin Wood,Quantifyingtheeffectsofgrazingonaquaticecosystems

11:05Alan Law,Along-termstudyoftheeffectsofherbivorybyEuropeanbeaveronaquaticvegetation

11:20 General discussion

11:35 Coffee

Session 2: (Chair, Stephen Maberly)

11.50Jordi Catalan,Predictabilityrequiresunderstanding:someparadoxesonpersistentorganicpollutantsandaquaticorganisms

12.20 Gareth Jenkins,Speciesinteractionsmayinhibitbiologicalrecoveryinacidifiedfreshwaters

12.35Núria Bonada,Biologicaltraits,evolutionaryhistory,andcommunityassemblyoffreshwaterbiodiversity

13.05 Ana Filipe,Usingtimetofirstdetectiontoimprovespeciesdistributionsmodels

13:20Margarita Florencio,Bioticinteractionsandenvironmentalvariabilitydeterminebiodiversitypatternsinmacroinvertebrateassemblagesoftemporaryponds


13:50 Lunch

Session 3: (Chair, Isabel Reche)

15.30 Jonathan Grey,Connectivity:cornucopiaorcurseforinlandwaters?

16.00Mireia Bartrons,Aquatic-TerrestrialLinkagesCreateaTrophicBypassthatReducesMethylmercuryinTerrestrialFoodWebs

16.15 Hugh Feeley, Smallheadwaterstreamsandtheirimportanceinfreshwaterresearch:Case-studiesfromIreland

16.30Eduardo García-Roger,Bet-hedgingstrategiesinthehatchingofrotiferdiapausingeggsfromtemporarypopulations


17:00 Coffee

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Session 4: (Chair, Jonathan Grey)

17:30 Isabel Reche,Inlandwatersasamodelsystemtostudymicrobialmetacommunities

18:00 Erika Hogan,NutrientlimitationofphytoplanktongrowthinArcticlakes

18:15Eleanor Mackay,Fromsmalllakestoglobalbiogeochemicalcycles:theinfluenceofmixingprocessesonphosphorusaccumulationandcycling


20:00 Dinner at the Palacio de Doñana

TUESDAY 15TH OCTOBER

Session 5: (Chair, Isabelle Durance)

9:30Nigel Willby,Whatcanlandscape-scaleapproachesteachusabouttheconservationandrestorationoffreshwaters?

10:00 Carles Alcaraz,Long-termchangesinthelowerEbroRiver:top-downversusbottom-upeffects

10.15Susana Bernal,Openingtheblack-box:theuseofexperimentalcatchmentstounderstandecosystemfunctionanditsresponsetoenvironmentalchange

10.30 General discussion

10.45 Coffee

Session 6: (Chair, Jodi Catalan)

11.00 Emili García-Berthou,Invasionbiologyandinlandwaters:fromconservationtocommunication

11.30 Belinda Gallardo,IsGreatBritainonthebrinkofinvasionalmeltdownofPontoCaspianspecies?

11.45Christopher Lejeusne,Invasivebrineanddecapodshrimps:whatcantheytellusaboutinvasionmechanismsinaquaticenvironments?

12:00Kit Magellan,Theroleofbehaviourinbiologicalinvasions:interactionsbetweeninvasivefishandnativeIberianspecies

12:15Marta Sánchez,StudyingfeedingrateinArtemiaprovideinsightsonthecompetitivesuperiorityoftheexoticA.franciscanaanditspotentialimpactinhypersalineecosystems

12.30 General Discussion

13:00 Lunch

15:00 GuidedtourofDoñanaNationalPark

20:30 Dinner at local restaurant

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TUESDAY 16TH OCTOBER

Session 7: (Chair, Nigel Willby)

9:30Stephen Maberly,Climatechangeeffectsonthefunctioningofinlandwaters:pervasiveinfluenceorminorfactor?

10:00 Aitor Larrañaga,Globalchange:perspectivesfromthenotsodrySpain

10:15Cayetano Gutiérrez,Theeffectofnaturalandanthropogenicstressorsonthestructureandfunctionofaquaticecosystems


11:00 Coffee

Session 8: (Chair, Emili Garcia-Berthou)

11:30Isabelle Durance,Freshwaterecosystemservices:anewwayofcommunicatingtheimportanceoffreshwatersandfreshwaterbiodiversity

12:00 Christopher Hassall,Urbanpondsandaquaticbiodiversity

12:15 Daniel Perkins,Land-useeffectsonstreamfoodwebsandservices


13:00 Lunch

Session 9: (Chair, Andy Green)

15:00César Alcácer Santos(CoordinadorGestiónEcosistémicadelAgua,FundaciónCentrodelasNuevasTecnologíasdelAgua),Fundingopportunitiesintheareaofaquaticecology

15:45

SessionsforSubgroupdiscussions.4mixedgroupsof5youngerscientistsand2groupsof5olderscientistsdiscussedtheirgeneralimpressionsonthestateofthesubjectarea.Inparticular,theywereaskedtodiscuss"Whereisfreshwaterecologygoing?"and"Whatcollaborationsmightbeinteresting?",withtheaimof2-4mainpointsfromeachgroupforeachquestion.

17:30 Coffee

Session 10: (Chair, Brian Moss)

18:00 Reportsfromdiscussiongroupsandgeneraldiscussion

20:00 Dinner at the Palacio de Doñana

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SUMMARy OF DISCUSSIONS

Our workshop was held in a relaxed andinformalatmosphereon theedgeofDoñana’shugemarismas(temporarymarshsystem) inaWorldHeritageSite.Therelativelysmallsizeofthemeeting,and the fact thateveryonemadea presentation, and no one was there only asa member of the audience, helped to fosteran atmosphere of interaction and less senseof hierarchy between very experienced andearly career scientists. Scientific meetings areusually organised in such a way that they arelargely one-way exercises. Most of the time,someone talkswhilst the rest listen. Therewillusually be questions after a talk, or in a laterdiscussionsection,butthesetooareessentiallyinteractions between only two people (thespeaker and the questioner) and only rarelydoesarealdiscussionensue.Inthisworkshop,whereamajorthemewasthedirectioninwhichthe subject of freshwater ecology is goingandis likelytogo,andhowtotakeadvantageof such predictions in future collaborations,we felt it useful to devote time to small-group discussions. So that discussions werenot dominated by the older and (perhaps)moreconfident,werandomisedmembershipingroupsoffivebutcreatedseparategroupsfromthe older and the younger participants. Thetopicsfordiscussionwere‘Whereisfreshwaterecologygoing?’and‘Whatcollaborationsmightbeinteresting?’Discussionsrangedmorewidelythan these, however, as well they should, withthe independent minds that good scientistsinevitablyhave.

One of us had pointed out that there wereconsidered to be some problems within theorganisation and promulgation of freshwaterecology in Europe. It was perceived (byterrestrial and marine ecologists) to be lessimportant than terrestrial and marine ecology,becauseofanemphasisonpracticalproblem-solving, and an orientation towards themediumofwater rather than towardsabstractecological problems, which are perceived tobe intellectually more challenging (at least bythose that are orientated towards that sortof approach). An approach to summarisingthe discussions, which were reported groupby group to a plenary session, is thus to

construct a SWOT (strengths, weaknesses,opportunities, threats) analysis for freshwaterecology and ecologists, with the potentiallyinteresting collaborations being presented asopportunities.

StrengthsThe strengths of freshwater ecologists wereperceived as a long tradition of making links,both intellectual and personal, with otherdisciplines. The talks given had illustrated thiswith examples, on the one hand, from animalbehaviour, concerning mating and aggressionin small fish, to the biogeochemical transfersof mercury from lakes by chironomids andof nitrogen from catchments to lakes, on theother. Secondly, freshwater ecologists havecontributed to the formulation of majorprinciples in ecology as a whole (the trophic-dynamic concept (Lindeman), the nicheconcept (Hutchinson), the winkling out ofpseudoreplication inexperiments(Hurlbert)) inthepast,andhavebeenparticularly important(with marine ecologists) in exploring the useof stable isotopes, particularly of carbon andnitrogen, in the elaboration of food webs,and the movements of carbon across thelandscape and into the waters. Freshwaterecology was also seen to have had a widescope,bothgeographical(infishbiogeographyand speciation), and in time (through thedevelopmentofpalaeolimnologytoafargreatersophisticationthanterrestrialpalaeoecology).

WeaknessesWeaknesseswereseeninadevelopingdegreeof isolationism compared with the breadth ofapproach of the past, (which was seen as astrength), a tendency to concentrate only onthe freshwater system with sometimes littleattention to the catchment, and a tendencyto publish the best work in non-specificjournals with high impact factors, which isunderstandable, but which camouflages thefreshwateroriginofthework.Theremightalsobe a more gentle pacing of the work, linkedwith emphasis on organisms with long life-historiesorpatterns inpopulationchangethatemergeonlyafterstudyofmanyannualcycles.Ithadbeenpointedout thatWinfriedLamperthad accused freshwater ecology of continualreinventionofthewheel,throughcreatingmoreand more examples of the same phenomena(studies on eutrophicated lakes, engineered

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rivers,drainedanddryingwetlands,populationcyclesdescribedbutnotanalysed,forexample).It was also felt that we might not be forwardenoughinadvertisingourselvesandourwork.If a scientific meeting of ecologists contains95% terrestrialpapersand5% freshwater, thefreshwater marketing needs to have 19 timestheimpacttomaintainparity.

ThreatsThreats were not perceived to be greatlydifferent from a continuation of our currentweaknesses. But despite the fact that manyproblems in the oceans can be tackledmuch more conveniently in freshwaters (andsometimes have already been exhaustivelystudied there), theprestigeof largegrants forexpensive ships and cruises may sometimesworktoourdisadvantage.

OpportunitiesMost interesting were the possibilities ofcollaborations, which reflect opportunities inthisanalysis.Generalperceptionswerethatwecouldadopttheconfidentattitudesofterrestrialecologistsandsimplypushourinterestsmore,that we could improve our communicationabilities tosellourresearch,andthatwehavenotingeneralbeendeficientindevelopingnewtechniques and fields. There was certainly acasefor ‘emerging from the water and thinking outside the cup’,butperhapsthatissomethingwe have often done, and perhaps reinventingthewheel isnotsuchabadthingif it leadstonewperceptionsof thewheel: theequivalentsof pneumatic tyres to replace iron-shod rims,lightweight alloys to replace heavy steel andimprovedgearingsystems,forexample.

Itwasfeltthatfutureresearchwouldinevitably(because of political influences reflectedin funding) be in the applied area, but thatneed not exclude a clever incorporation offundamentalstudies.Thefuturewillalsodependmore on collaboration because specialisttechniquesdemanddeeperskills(inchemistryand bioinformatics and statistics for example).There was also an opportunity to improvecommunicationtechniques,especiallyasusersofourresults,whoprovidefunds,andstipulaterequirements, expect clear communicationof results and their implications. One majorpoint made by a speaker cognizant with theintricacies of submitting EU grant proposalswas in thinking about the reviewers (often

non-specialists), so that plain English was apriority.Therewasevidence,thataswithotherscientists, much could be learned throughwider collaboration as required to obtainthe large EU grants, though it would need amaintenance of the divergent thinking of pasttradition.Techniquesmightincreasinglyinvolvetheuseofsocialmedia. Indeed,severaloftheworkshop participants experimented with theuseofTwittertobroadcasttheworkshopitselfbefore and during the event, and presentedthe resultsduringourdiscussions.Twitterwasmore widely established among the BritishparticipantsthantheSpanish,andseveraloftheSpanish participants decided to adopt Twitterasaprofessionaltooldirectlyasaconsequenceoftheworkshop.

Making time for collaborative thinking as wellas practical working could also pay dividends.There were ways to help the process. Beingcreativeinotheractivitiesoutsidesciencecouldhelp increase creativity within it. It was worthallocatingsometimetoriskyresearchwhilstalsocarryingoutthebread-and-butterresearchthatisenforcedbythepressuresofmodernfundingand institutional management. In the future,deep expertise will continue to be required,buttoogreataspecialisationcanbehazardousin a world of changing fashions in funding.Flexibility is needed. Learning new techniquesis always a good thing. Familiar techniquesapplied repeatedly in different situations canbecome prisons. There are opportunities toapplynewtools(e.g.stableisotopes,genomics)especiallytoinvestigateprocesses,butitshouldberememberedthatthebestresearchisalwaysdrivenbyquestions,nottechnology,andfashioncan be a false seducer. In general, freshwaterecologists have probably not thought enoughabout the links with evolution, notwithstandingthe excellence of studies on speciation infish and on adaptive radiation through traits.Finallymodels, nowwidelyused, aregenerallyrestricted and do not include nearly enoughattentiontomicrobiallydrivenprocessesontheone hand, and larger organisms such as birdsandmammals(andoftenevenfish)ontheother.It is necessary to think big. Peter Medawar, aNobelPrize-winningphysiologistoncesaidthatimportant answers come only from importantquestions.

EUfundingwasidentifiedasessentialtoenablefuturecollaborativeresearchoninlandwatersin

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theUKandSpain, especiallygiven thecurrentchallenging financial situation for Spanishresearch. There are many commonalities forcollaboration,especiallybetweencountries likethe UK and Spain with markedly contrastedterrain, climate and recent geological history.Thevaluationofecosystemgoodsandservicesis currently of high and growing profile. Itprovides opportunities for working with otherareas in the social sciences and engineering.It would be valuable to use this as a platformfor creating a desired increase into morefundamentalresearch,andfundingforlong-termstudies,anditcontributestocommunicationofthebenefitsofconservation,and thechangingof attitudes among the public and politicians.It also increasingly uses remote sensing andgeographical information systems, techniquesthathavenotbeensowidelyusedbyfreshwater

ecologists but approaches that allow researchon remote areas that might not otherwise bepossible, as well as going back in time e.g. toretracefloodingpatternsinDoñanabackinthe1980s before these were monitored. Beyondthatthecommonalitiesofinvasiveandmigratingspecies, climate and other global change, notleastfloodsanddrought,andtheimplicationsoffragmentation of the landscape, offer contrastand comparisons for future work linking Spainand the UK. Doñana was an ideal place to bereminded of such themes, as Europe’s mostimportant wintering area for ducks and othermigratory waterbirds that breed in northernEurope,andasahighlyprotectednaturalareasurrounded by transformed landscapes suchasaseasideresort,strawberryfields,andotheragriculture.

AbSTRACTS

Long-term shifts in the lower Ebro River

Carles Alcaraz, IRTA, Sant Carles de la Ràpita, Spain

TheEbroRiver is ca.930km longanddrainsan area of 85534 km2 crossing the North-easternpartof the IberianPeninsula. It isoneof the most important rivers flowing into theMediterranean Sea, with a mean annual flowof about 426 m3/s, but there are significantdifferences between dry (118 m3/s) and wet(569 m3/s) years. In the lower Ebro River(100 km upstream the mouth) there are twolarge reservoirs (Mequinença and Riba-roja)built in the 1960s for hydropower purposes,thusimpactingriverhydrology,geomorphologyand ecology. The lower Ebro River has alsorecently undergone a regime shift to amacrophyte-dominated from a phytoplankton-dominatedsystem.Twoinitialhypotheseshavebeen proposed to explain the collapse of thephytoplankton:bottom-up(oligotrophicationbythediminutionofphosphorus);top-down(zebramusselintroductionandcolonization).Thezebramussel (Dreissena polymorpha) is among themost invasive organisms worldwide with welldocumentedecologicalimpactsonecosystems

functioningandnativefaunabesides imposinghugeeconomiccosts. Inordertocheckthesehypotheses we gathered data (from 1990 to2005)onwaterquality,hydrologyandbiologicalcommunities(phytoplankton,macrophytesandzebramussel)fromexistingdatasets.APrincipalComponents Analysis (PCA) was carried outin order to explore patterns of associationamong limnological variables, GeneralizedAdditiveModels(GAMs)wereappliedtomodelthe response of chlorophyll concentration totemporal, and the relationship of chlorophyllto limnological variables was analyzed byGeneralized Linear Models (GLMs) using aninformation–theoretic approach. Since musseldensity has been proposed as a key factordetermining its impacts we also constructeda demographic model, using a monthly timestep,mortalityandfecunditywascontrolledbytemperatureandpopulationgrowthwaslimitedby a carrying capacity calculated from localdata.Resultsclearlyshowthatthedecreaseinphosphorus is the main cause of chlorophyllreduction, and thus triggering the ecosystemshiftthroughanincreaseinwatertransparencyandthesubsequentcolonizationofmacrophytes.The decrease in dissolved phosphorus (GLMsmodels) had a relative importance 14 timeshigherthantheincreaseinzebramusseldensitytoexplainthevariationoftotalchlorophyll,andriver hydrology did not present a significantinfluence on the decreasing trend of total

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chlorophyll along the study period. This novelecosystemshiftiscausingremarkablechangesin the biological communities beyond thedecreaseofphytoplanktonandtheproliferationof macrophytes, such as massive colonizationof Simulidae (black fly) and other changesin the benthic invertebrate communities thatare currently investigated. Mussel modelpredictionsatalocalscalemayadditionallybehelpfulindevelopingadequatecontrolplansbyforecastingmanagementeffects.

Taking the Trophic bypass: Aquatic-Terrestrial Linkage Reduces Methylmercury in Terrestrial Food Webs

Mireia Bartrons1, Claudio Gratton2, Brian J. Spiesman2, M. Jake Vander Zanden1

1 Center for Limnology, University of Wisconsin, Madison, USA

2 Department of Entomology, University of Wisconsin, Madison, USA

Ecosystemscanbelinkedbythemovementofmatterandnutrientsacrosshabitatboundariesthroughavarietyofprocesses,includingaquaticinsect emergence. Aquatic organisms tend tohave higher concentrations of certain toxiccontaminants such as methylmercury (MeHg)compared to their terrestrial counterparts. Ifaquatic organisms come to land, terrestrialorganisms that consume them are expectedto have elevated MeHg levels. But emergentaquatic insects could have other impacts aswell,suchasalteringconsumertrophicposition,orincreasingecosystemproductivityasaresultof nutrient inputs from insect carcasses.Here,wemeasureMeHgconcentrationsinterrestrialarthropods at two lakes in northeasternIceland, and use carbon and nitrogen stableisotopes to quantify aquatic reliance andtrophicposition.Contrary toourexpectations,terrestrial consumers that consumed aquaticprey had lower MeHg concentrations. MeHgconcentrations were positively correlated withconsumer trophic position. Path analysis wasusedtoexaminethedirectandindirecteffectsof aquatic reliance and trophic position onMeHg.Acrossallterrestrialarthropodfocaltaxa(Lycosidae,Linyphiidae,Acari,Opiliones),aquaticreliancehadsignificantdirectand indirect (viachanges in trophic position) negative effects

on terrestrial consumer MeHg. Overall, ourresults highlight the potential for cross-habitatlinkages to affect MeHg dynamics via severalmechanisms, including effects on consumertrophicposition.Terrestrialarthropodsthatfedon aquatic insects had lower MeHg, whichruns counter to the conventional wisdom thataquatic systems are a universal source ofMeHg contamination to surrounding terrestrialecosystems.

Keywords: Ecosystem Linkages, Food Web,AquaticInsects,Methylmercury,StableIsotopes

The use of experimental catchments to understand ecosystem function and its response to environmental change

Susana Bernal, Centro de Estudios Avanzados de Blanes (CEAB-CSIC), Girona, Spain

Freshwaterecosystemsareexcellentintegratorsof ecosystem processes occurring at thecatchment-scale because they are recipientsof waters draining throughout the catchment.This intimate relationship between freshwaterand terrestrial ecosystemsallowsapproachingchallengingquestionsinourtoday’sworldsuchas theeffectofclimatechangeonecosystemnutrient fluxandcycling.While rare, long-termrecordssuchasthosecollectedattheHubbardBrook Experimental Forest (NH, USA), offer aunique opportunity to disentangle effects ofclimate from other anthropogenic influences.Our study indicates that climate alone cannotexplain the occurrence of a dramatic >90%dropincatchmentnitrateexportoverthepast46years,despite longergrowingseasonsandhighersoiltemperatures.Thestrongestclimateinfluence was a warming-induced shift in soil-water flow paths within the catchment, butthiseffectexplainedatbestonly~40%of thenitratedecline. Incontrast, at least50-60%oftheobservedchangeintheNexportcouldbeexplained by the long-lasting effect of forestcuttingintheearly1900’sontheNcycleofthesoil and vegetation pools. Our analysis showsthat past events can obscure the influence ofmodern-daystressesontheNcycle,evenwhenanalyseshavetheadvantageofbeinginformedby half-century long data sets. These findingsraisefundamentalquestionsabouthoweffectsofclimatechangecanberesolvedonterrestrialecosystems still under the influence of pastperturbations.

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biological traits, evolutionary history, and community assemblage of freshwater biodiversity

Núria Bonada, Grup de Recerca Freshwater Ecology and Management (FEM), Departament d’Ecologia, Facultat de Biologia, Universitat de Barcelona (UB), Spain

Freshwater ecosystems hold an enormousnumber of species despite occupying a verysmall fraction of the Earth’s surface. However,under the current freshwater crisis, many ofthese species are highly threaten, some havebeenrecentlyextinct,andothersaredecliningmuch faster than those in terrestrialormarineecosystems. Understanding global patterns offreshwater biodiversity is thus a key issue forits conservation but still remains a challengein macroecology and macroevolution. Inparticular, despite biodiversity is a very broadconceptandincludemanydifferentdimensions(from genetic to ecosystem diversity), mostmacroecologicalandmacroevolutionarystudiesdealwithsimplemeasuresofbiodiversity,suchasspeciesrichness.Thesesimplemeasuresdonot account for species identity and considerall species and their relationships as equal.Species differ in their functional (what theydo) and evolutionary (from where they comefrom) characteristics and therefore thesefeaturesshouldbeconsideredwhenanalysingbiodiversitypatterns.Thus,siteswithfunctionallycomplementary species would be morediverse that sites with functionally redundantspecies because they hold broader functionalinformation. Likewise, sites with phylogeneticdistant species would be more diverse thansiteswithcloselyrelatedspeciesbecausetheyintegratemoreevolutionary information.Basedon this idea, we showed that macroecologicaland macroevolutionary patterns might differdepending on how we consider diversity.Stream macroinvertebrates showed that themost accepted macroecological pattern ofspecies richness in latitude was followed byspecies richness and functional diversity butnot by phylogenetic diversity. When lookingat the macroevolutionary pattern, speciesdiversification along the evolutionary timefollowed what is known for all the eukaryotesbut changes in functional diversity of taxashowed that most recent clades have lowerdiversity than older clades. Only by analysingthedifferentdimensionsofbiodiversityinspace

and timewewill be able tounderstandglobalpatterns of species and address appropriatedconservationmeasures.

Predictability requires understanding: some paradoxes on persistent organic pollutants and aquatic organisms

Jordi Catalan1,2

1Centre de Recerca Ecològica i Aplications Forestals, (CREAF), 2 Centro de Estudios Avanzados de Blanes (CEAB-CSIC), Spain

The current global change provides countlessopportunities for research in ecology.Research on these issues has a societaldemand for prediction. In this talk, the aimwas to highlight the need for understandingthe mechanisms behind observed patternsin order to extrapolate results beyond thedetailedcasestudies.Excessiveconfidenceonthe statistical associations between observedpatterns can lead to serious inconsistenciesand errors in projections of future scenarios.To illustrate these contingencies, we lookedat some paradoxes arising from patterns inthedistributionofpersistentorganicpollutants(POPs)infreshwaterorganisms.

The consequences of the progressiveaccumulation of POPs in nature are largelyunknown.However, thiswasnot thesubjectofthe talk. Examples of the distribution of thesecompoundsinfreshwaterorganismswereusedto illustrate how necessary is an adequateknowledge of physicochemical principlesand biological idiosyncrasies of organisms toextrapolateoracceptexplainationsforobservedpatterns.

Polychlorobyphenyls (PCBs) were used asdemonstrative compounds. The productionand use of PCBs was banned long ago in the1970s, but their slow fate in the environmentdeterminesthattheyarespreadingthroughoutthe planet and bioaccumulating in the biota.They are interesting as model compoundsbecauseincludeanumberofcongenerswithadifferentamountofchlorination,whichultimatelydetermine individual volatility properties andpartitioncharacteristicsbetweenair,waterandlipids(i.e.,livingbeings).

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PCBs reach remote areas, far from they wereproducedandused,byatmospheric transportand then dissolve partially in water andeventuallyaccumulateintheaquaticorganism.The interesting issue is that the proportion ofthe different PCB congeners may vary acrossthe different compartments in this pathwayduetotheirspecificphysicochemicalfeatures.In the atmosphere of remote sites, the lesschlorinated congeners, which are lighter andmore volatile, usually predominate. Whenthey dissolve into the water, the ratio amongcongeners tends to be similar because themore-volatile dissolve less. Then, when thecompounds bioaccumulate, the less volatilebecome more abundant within the organismsbecausetheyaremorehydrophobic.Thus,theshort story is that the most abundant in theair should become the less abundant in theorganismsaccordingtotheoryandconsideringorganismsessentiallyasasimplelipid(fat)ball.

In fact, ithasbeen foundthat the lessvolatilePCBs are relatively more abundant in themacroinvertebratesofmountainlakes,reversingthetendencyintheairoftheselocations,whichshowahigherproportionof themostvolatile.Fine,theywerefollowingtheexpectedpattern,and several species were showing the same.But then, started to appear species with thecompletely opposed pattern: more relativeconcentrationofthemostvolatile,asintheair.What was wrong with the expectations? Whatdid these “outlier” species have in common?Allofthemwerespeciesthatrespireairratherthan water despite being aquatic. They eithergetapartofthebodyoutsideandkeepair inabubbleorevenarepermanentlyunderwaterbutwithasystem(plastron)thatallowsthemtokeep an air layer attached to the ventral partofthebodysothatgasesinthis“airchamber”exchangewithwater.Thus,fineagain.TheonesrespiringwaterhaveaPCBsignatureclosertowater concentrations and the ones respiringairasignatureclosertoairconcentrations.Weunderstandtheprocessagain;let’smakesomecalculations check it. Ops! It turns out that atthermodynamicequilibriumrespiring in theairorwaterdoesnotmakeanydifference in thefinal concentrations. Both types of organismsshould show the same PCBs profiles. In fact,thedifferencebetweenair-lipidpartitioningandwater-lipidpartitioningisexactlycompensatedbythepartitioningbetweenairandwater.Wheredoesthedifferenceinobservedpatternscomefromthen?Perhapsthesimplethermodynamic

“fat ball” model is not enough. That is, weare observing patterns resulting from kineticprocesses: food uptake, excretion with faecesandexchange through therespiratorysystem.The key points are that ventilation rates inthe respiratorysystem fororganisms respiringwater are higher than for those respiring airasoxygenconcentration is30timeshigher inair than in water and that coefficients of PCBpartitionbetweenair-lipidandwater-lipiddifferinordersofmagnitude.

Beyondthedetailsofthecase,thetakehomemessage is that, by simple association ofpatterns,wedonotexplain theprocess.Evenwhenthereissometheorybehind,thesimplestmodelmayresulttoosimple.Thisisparticularlytrue for living systems that are far fromthermodynamic equilibrium. Consideration ofphysicochemicalprinciples,biologicaltraitsandsomecalculationsmayhelpquestioningaboutthe mechanisms behind observed patterns.Anotherexample,aboutPCBaltitudinalpatternsin sediments and fish was also presented toillustrate how easy is to accept inappropriateadhocexplanationswhentwopatternsmatch.

Freshwater Ecosystem services, challenges and opportunities for freshwaters and freshwater biodiversity

Isabelle Durance and the Duress team, Cardiff University, United Kingdom

There isgrowingconsensusthat inappropriatevaluation of the world’s ecosystem serviceshaveledtowidespreaderrorsinenvironmentalmanagementwithassociatedsocialdisbenefits.Freshwater ecosystems are a prime example:when managed appropriately, they providemajor services such as fish production, watersupply, nutrient transport, health benefits andrecreation.However,theseserviceshavebeencompromised extensively because they areseldom recognised in catchment activities.Pressuresonriverecosystemserviceswillgrowinfutureaslanduseintensifies,waterdemandsincreaseandclimatechangesfurther.

Sustainable management of river ecosystemservices depends on understanding theprocesses that underpin them. In particular,thereisaneedtoquantifyhowservicesdepend

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on riverorganisms,and toassesswhetherarethere biodiversity thresholds under which aservicecannotbedeliveredoriscompromised.While our understanding is that the level andstabilityofecosystemfunctionstendtoimprovewith increasing biodiversity, the nature of therelationshipthatlinksbiodiversitytoecosystemservicesstillneedstobedefined.TheDURESSproject,a£3million trans-disciplinaryresearchprogramme funded by NERC, is seeking toassess quantitatively i) how biodiversityand service delivery are linked; ii) how riverbiodiversityaffectstheresilienceofecosystemservicedeliverythroughtime;andto iii)definehowchanges incatchmentsandclimateaffectservices delivered by river biota in order toinformimprovedmanagement.

First lessons from this project are that i) theecosystemserviceapproachrequiresaholistic,real life, large scale approach; but also that ii)the ecosystem service approach - by shiftingfocus from biodiversity or habitat to service– bridges the gap between natural and socialsciences,andbringsscientistsoutoftheirzoneofcomfort.Clearly,addressingthemajorsocietalchallengesofourtimeswillrequireamajorshiftinthewayourenvironmentismanagedandanout of the ordinary approach. The ecosystemserviceapproachisnotwithoutdifficulties,butfreshwaterecologists,withtheirintegratedandinterdisciplinary catchment tradition, are alsoclearlythebestsuitedtoleadthepath.

Small headwater streams and rivers and their importance in freshwater research: Case studies from Ireland.

Hugh B. Feeley,School of Biosciences, Cardiff University, United Kingdom

Headwater streams and rivers constitute ahigh percentage of the riverine network inmany countries worldwide (e.g. Ireland ~77%,U.S. ~85% and U.K. ~90%). Their extensivespatial distribution, range of physiochemicalcharacteristics and variable land-use coverprovide an unlimited array of ecologicaltemplates ideal for research opportunities.Using headwaters categorised into coniferforest cover classes throughout Ireland myresearchhasindicatedthesignificantreductionof inorganic drivers (e.g. SO42- and NO3-) ofacidity during episodic storm events and thesignificant increases in organic acidity arising

from increases in dissolved organic carbon(DOC).TheconcentrationofDOCduringepisodicevents increases with increasing forest coverandinterestingly,concentrationshaveincreasedby up to 35% over the last 30 years in thesesmall peaty catchments. Ecological recoveryin the same forested headwaters seems tohaveimproved,althoughstormeventfrequencyand associated low pH reduces acid-sensitivetaxa periodically. Nevertheless, ecologicalresistance and resilience has increased. Theextensive number of headwaters with varyingland-use types in close proximity (<2km) hasalso allowed us to examine the longitudinalextent of acid impact on macroinvertebratepopulations and exclude the effects ofcatchmentphysiochemicalcharacteristicssuchas aspect, soil, geology, elevation etc, andallowed us to highlight the limited (~1.5km)ecological impact. Other research has alsohighlighted the importance of headwaters inregional macroinvertebrate biodiversity (12-30%), and emphasises their importance infreshwaterconservation.Nevertheless,extremeclimatic events may reduce this biodiversitysignificantly which may have knock on effectsonthesustainabilityofecosystemservicesintothe future.Whileheadwatersarevital in futurefreshwaterresearch,aholistic,multidisciplinaryapproachacrosstheecological,environmental,social, cultural and economic disciplines areessentialforthesuccessfulcommunicationandimplementationofourresearch.

Using time to first detection to improve species distribution models

Fereira, M.1; Filipe, A.F.1; Magalhães, M.F.2; Beja, P.R.1

1 CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos da Universidade do Porto, Portugal

2 Centro de Biologia Ambiental, Departamento de Biologia Animal, Faculdade de Ciências de Lisboa, Lisboa, Portugal

Sinceearlytimesresearchersworriedaboutthepossibilitythatanorganismispresentbutmightnotbedetectedduringasurvey.Infact,speciesdetectability is a primary cause of biodiversitydata uncertainty, particularly when modellingthe distributions of species inhabiting freshwaters.Herewepredict fishdistributionswhileaccountingdifferentdetectionprobabilities for

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the Sabor catchment (Douro basin, IberianPeninsula). First, we estimate the speciesprobability of detection using a new Bayesianapproach based on a time-to-first-detection.Second, we incorporate such detection inlogisticregressionmodels.

Timetodetectionvariedwithsamplesitedepthand species analysed. Substantial differenceswere found when contrasting results of thelogistic regression models that do not correctfordetectabilitywiththeonesthatincorporatedetectionestimates.Forthemajorityofspeciesno more than five minutes was needed toachievehighprobabilityofdetection.

Results of our study highlight the importanceof incorporating detectability estimates whilepredictingspeciesoccurrences.Notaccountingsuch source of uncertainty can certainlyinfluence the results obtained, with strongimplications on the accuracy and reliability ofbiodiversitydatabasesaswellasinregionalorglobalconservationandmanagementplans.

biotic interactions and environmental variability determine biodiversity patterns in macroinvertebrate assemblages of temporary ponds.

Margarita Florencio Diaz, Universidade dos Açores, Terceira, Portugal

Temporary ponds are water bodies thatpresentrecurrentdesiccationphaseofvariableduration.TheDoñanaNationalPark(SWSpain)can present more than 3000 water bodiesusually being formed after the first rains ofautumn or winter. The macroinvertebrateorganisms inhabiting temporary ponds (mainlycoleopterans,heteropteransandodonates)areadapted to the typical fluctuations of theseponds, developing strategies to disperseand survive pond desiccation. We exploredmacroinvertebrate biodiversity patterns inDoñana temporary ponds across time andspace. A highly nested pattern was detected,whichconsistsinspecies-poorsitesharbouringsubsetsofthespeciescontainedinthespecies-richsites.Detectingproperlynestedbiodiversitypatternsand thebackgroundmechanismshasimportant consequences for conservation. Wedetected that weak dispersal limitations in thepondnetworktogetherwiththeenvironmentalvariabilitywerethemaindriversoftheobserved

nested pattern. Therefore, the best strategyfor conservation is to guarantee the highconnectivity and heterogeneity in the pondnetwork to support the high diversity of thesystem. We also identified different phasesduringtheannualcyclesofpondinundationanddesiccation.During the fillingphase, thepondinundation occurs in the whole network afterthefirstheavyrainfalls.Duringtheintermediatephase, the establishment of the assemblagesandtheorganisms’lifecyclesoccurs.Thedryingphasestartswhenthe firstpondsareclose todesiccation and organisms thus develop theirstrategies facingdesiccation.During the fillingand the drying phase, we detected Urodele’spredationonthemacroinvertebrateassemblagestructures. We also identified competitiveexclusion and habitat segregation operatingtogether to determine spatial assemblagesegregations.Wealsodetectedthatthedegreeof nestedness increased after the first pondinundationuntilthedryingphase.Inthedryingphase, the simultaneous occurrence of dryingponds under stressing conditions and morestable non-drying ponds determine a non-nested macroinvertebrate pattern. Temporalvariability in temporary ponds must be takenintoaccounttodetermineproperlyprioritiesforconservation.

Key words: macroinvertebrate assemblages,temporary ponds, biodiversity patterns,conservation,spatio-temporalvariations

Is Great britain on the brink of invasional meltdown of Ponto Caspian species?

Belinda Gallardo, Aquatic Ecology Group, Department of Zoology, University of Cambridge, United Kingdom

Thisstudyseekstoassessthefullscopeofthethreatposedbyahigh-riskgroupoffreshwaterinvaders originating from the Ponto-Caspianregion(SEEurope)acrossBritain.Approximately40% of invasive freshwater invasive speciescurrentlyknown inBritainarereported for thefirsttimefromcoastalcatchmentsoftheThamesriver basin district, followed in importance bythe Anglian and Humber districts. At least 15out of the 23 alert Ponto-Caspian organismsinvestigated are well established in the RhineestuaryandDutchports.Fourofthesespecies(Hemimysis anomala, Dikerogammarus villosus, D. haemobaphes and H. invalida)haverecently

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crossed the channel and established in GreatBritain. Linear regression models suggest therestareunderacriticalriskofbeingtransported,with four species predicted to have arrivedalready to Great Britain (Echinogammarus ischnus, Jaera istri, Limnomysis benedeni and D. bispinosus).Accordingtospeciesdistributionmodels performed with data on the currentspatial distribution of Ponto-Caspian invaders,the cumulative risk of invasion of multiplePonto-Caspian species, thus invasionalmeltdown, ishighest in theSEofEnglandanddecreases north and westwards. GeneralizedLinear Models used to address the responseof Ponto Caspian invaders to water chemistrywere able to explain between 30 and 70%of the species presence-absence. Alkalinitywas the most important factor in all modelswith Ponto Caspian invaders showing highprobabilities of successful establishment atalkalinity levels higher than 120 mg/L, whichcorrespondtomostofEnglandandtheeasternpartofWales.Overall,thepredictivemodelsandmapsdevelopedinthisstudyprovideameansfor a scientifically informed prioritization ofspeciesandriverbasinsforthemanagementofexistingand future invasionsofPontoCaspianspecies. To conclude, we have compiledenough information to make the case thatGreatBritainmightbeonthebrinkofinvasionalmeltdownand, asaconsequence,confrontingthe problem of alertPonto-Caspian invasivespecies is a vital element for nationalbiosecurity.

Invasion biology and inland waters: from conservation to communication

Emili García-Berthou, Institut d'Ecologia Aquàtica, Universitat de Girona, Spain

Freshwaterecosystemsarevery important forbiodiversityconservationandamongthemostthreatened worldwide. This is well exemplifiedin the Iberian Peninsula with most freshwaternative fish being endemics that are decliningduetoseveremultipleenvironmentalpressures.One of these pressures are invasive alienspecies. I provide an overview of invasionbiology using our research on freshwaterfishes in the Iberian Peninsula. Five classicalquestionsofinvasionbiologyare:Whatarethedistinctive features of invasive species? Whatdetermines invasibility of ecosystems? Whydo these invaders do so well and where do

theycomefrom?Whataretheeffectsoftheseinvasions?Andhowcanwemanagethisissue?Although we have advanced much on theanswer to thesequestions,manyuncertaintiesremain that call for a precautionary approach.Probablythemostunsolvedofthesequestionsishowtoreducethefrequencyandmitigatetheimpactsofinvasivealienspecies.Improvementofseveralcommunicationaspectsisoneofthekeytoolstoreducetheexponentialincreaseofthisenvironmentalissue.

bet-hedging strategies in the hatching of rotifer diapausing eggs from temporary populations

Eduardo M. García-Roger, Institut Cavanilles de Biodiversitat i Biologia Evolutiva. Universitat de València, Spain

Habitat unpredictability is a local adaptationfactor shaping life-history traits in aquaticorganisms. In the case of rotifers, whichwere used here as model organisms, such anuncertainty may select for the evolution ofbet-hedging through risk-spreading strategiesindiapausingegghatching.Thismeans thatafractionofdiapausingeggsinwildpopulationsdo not hatch even when the conditions arefavourable for population growth. Thus, thereis a remaining fraction of viable diapausingeggs waiting on stand by in the sedimentsfor longer periods. According to theory, it isexpected that the incidence of bet-hedgingstrategies for diapausing egg hatching willbe higher in more variable habitats. However,there is still little empirical evidence tosupport this prediction. This is most likelydue to the difficulties in accomplishing therequirements needed to identify and analyzebet-hedgingstrategies,avoidingconfusionwithgenetic variation and phenotypic plasticity.Essentially,theserequirementsare:(1)maternalcontrol over offspring phenotype, and (2)populationdifferentiationassociated tohabitatpredictability.Preliminaryanalyseshaveshowedagradientofpredictabilityinhabitatsoccupiedby the rotifer Brachionus plicatilis, and theexistence of a significant positive correlationbetween hatching fraction of diapausing eggsand an index of habitat predictability. Thissuggests that environmental variance in thismodelsystemtendstodecreaseasitincreasesthe frequency of good years for populationgrowth. Our recent research has also showed

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evidence of maternal control over offspringphenotype respect to their hatching pattern.Typically, the first diapausing eggs producedexhibited longer diapauses than diapausingeggsproducedlater.Althoughgeneticvariabilitycannot be completely discarded, our resultssuggest that variation in diapause duration islikely tohaveevolvedby thespreadofabet-hedgingstrategy.

Keywords: Bet-hedging,Diapause,Evolutionaryecology,Habitatunpredictability,Rotifers.

Freshwater birds as major players on the aquatic stage

Andy J. Green, Departmento de Ecología de Humedales, Estación Biológica de Doñana-CSIC, Spain

Since Hurlbert & Chang published a seminalpaper on “ornitholimnology” in 1983 (PNAS809: 4766-4769), surprisingly little attentionhas been paid to the role of birds in aquaticsystems. Ornithologists tend to focus on thepopulation ecology of their study species,without considering their influence on theecosystems they inhabit. Aquatic ecologiststend to ignore birds, as illustrated by theirnear or complete absence in textbooks suchas Lampert & Sommer’s Limnoecology andWetzel’s Limnology. However, birds are oftenmore important than fish in many freshwatersystems,especiallyshallowortemporaryones.UsingexamplesfromSpainandelsewhere,wepresentareviewofthelimnologicalroleofbirdsin thehopeofstimulating further research.Aspredators, grazers and ecosystem engineerstheyhaveaprofoundeffectontheabundanceofotherorganismsandonecosystemfunctioning.As such, waterbirds provide many ecosystemservices (reviewed by Green & Elmberg 2013Biol.Rev.)Theyinfluencesedimentstabilityandsuspension,andtheswitchbetweenclearwaterandturbidwaterstates.Owingtotheirmobility,theyplayan important role innutrientcyclingand can cause guanotrophication. They canhaveamajor influence inmethaneproductionandotheraspectsofbiogeochemicalcyclinginwetlands.As ideal vectors for thedispersal ofplankton,macrophytesandmacroinvertebratesthey have a central role in maintenance ofbiodiversity and in metapopulation dynamics,andareespeciallyimportantintheredistributionof these organisms in response to climate

change. Waterbirds also disperse parasites,pathogens and invasive species betweenaquatic systems, and can also be vectorsof heavy metals and other contaminants.Much more collaborative research betweenlimnologistsandornithologistscanimproveourunderstanding of aquatic systems. To quoteComin & Hurlbert (2012 Hydrobiologia) a “fullintegrationoftheecologyofaquaticbirdswiththeecologyoflakesandriversisfaraway”.

Keywords: waterbirds,ecosystemservices,ornitholimnology,seeddispersal,guanotrophication

Connectivity: cornucopia or curse for inland waters?

Jonathan Grey, Queen Mary University of London, United Kingdom

Inland waters are not isolated ecosystemsandmustbeconsidered in theperspectiveofa larger landscape unit to include the entiredrainagebasinifwearetomaintaintheintegrityof their ecosystem structure and processes.Connectivity is thus crucial and approachessuchasstableisotopeanalyseshavebeenkeyto illustrate the importance of movements oforganic matter into them from the land, andthe regulatory roles of fish that move amongthewatersandbirdsandmammalsthatmigratebetweenthewatersandtheland.Inlandwatersalso play a regulatory role in the transfer ofcarbon through the hydrological cycle, andreleaseofthatcarbonbacktotheatmosphereasvariousimportantgreenhousegases,ratherthan just conduits between the land and theoceans.The incorporationofmethane-derivedcarbon into food-chains identified by distinctstable isotope values from biogenic methane,has not only caused us to re-evaluate therelative importance of chemosynthetic versusphotosynthetic production in inland watersbut also highlights the importance of biologyin mitigating greenhouse gas mediation fromterrestrialsourcesthroughaquaticecosystemstoatmosphericsinks.

However, the likelihood of human inducedstressors being introduced to inland waters isalso enhanced through connectivity. Excessnutrients applied to agricultural land, as wellas mobile fine sediments from regularly tilledfields, contaminants from urban landscapes,

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and the introduction of invasive non-nativespecies are all promoted throughconnectivityand are clearly beginning to act in concertwith climate change. While palaeolimnologyhas been influential in identifying the start ofthe industrial revolution as a turning point inthe ‘quality’ofstandingwaters,andhencethelabelling of pre-industrial revolution structuraland functional conditions as a pristine stateidealtoaimforintermsofrehabilitation,humanshave been modifying the wider landscapethroughout the drainage basin for thousandsrather thanhundredsofyears. Towhatextentthen should we be viewing, for example,changing trends inwatercolour influencedbydissolved organic carbon against these muchlongertermpervasivehumaninfluencesinthecatchment?Iraiseandexploresuchquestionsusing a variety of stable isotope studies fromthepast25years.

The effect of natural and anthropogenic stressors on the structure and function of aquatic ecosystems

Cayetano Gutiérrez Cánovas,Ecología Acuática, Universidad de Murcia, Spain

Chronicstressmodifiesthestructureandfunctionof ecosystems through different processes.Despite that some convergent responseshave been found, as changes in communitycomposition and a reduction in diversity,there is unclear how this may affect to theprocessesexplainingchangesinbetadiversityandecosystemfeatures.Inmyresearch,Iusedstream macroinvertebrates to explore thesequestions,astheyofferinterestingpropertiestotestecologicalhypotheses.Astheseorganismsrespond tomarkedenvironmentalhabitats,weusenaturalandanthropogenicstressgradientstoseeifthedegreeinwhichtheregionalpoolof species isadapted toa typeof stress,maycause patterns that help to predict responsesto ongoing global change. In a first work, Ifoundthatnaturalandanthropogenicstressorsreduced species richness and generatecontrasting patterns in beta diversity thatarise through different mechanisms. Whilespeciesturnoveralongnaturalstressgradients,nested subset of species developed overanthropogenic stress gradients. In a secondwork, we estimate some ecosystem featuresfrom a multidimensional space composed of

axesthatrepresentedthevariationinbiologicaltraits of the aquatic community. We used thisreduced space as proxy of the functionalnichetoestimatemeantaxonniche(functionalrichness at taxon level), niche similarity (thepercentage of niche overlap between taxonpairs), community niche (functional richnessat community level), functional dispersion(functional diversity, as mean departure fromcommunitycentroid)andfunctionalredundancy(sum of overlapping areas between speciespairs).Wefoundsimilarfunctionalresponsestonaturalandanthropogenicstress,wheremeantaxon niche and niche similarity augmentedwith increased stress, and community niche,functionaldispersionandfunctionalredundancydecreasedwhenstressintensityaugmented.Thereductioninfunctionalrichnessarosefromthedevelopment of nested subsets of communitytraits along stress gradient. The results ofthese studies may have strong conservationimplications and may help to predict theecosystemresponsestoglobalchangeandtoelucidatehoworganismscolonizedandevolvedinstressfulhabitats.

Urban ponds and aquatic biodiversity

Chris Hassall, University of Leeds, United Kingdom

Workingonwetlands inurbanareas involvesauniquesetofproblemsandopportunities.Urbanareasaregenerallyconsideredtobe“unnatural”regions that contain little or no biodiversity.Furthermore, ponds themselves are thoughtto be insignificant due to their small size andvariable quality. However, in the aggregateponds can provide a substantial landscape-levelbiodiversityaswellasgeneratinggreatly-enhanced connectivity across otherwiseimpermeable built-up areas. Increasingconcern over the capacity of species to shifttheir ranges in response to climate changehas led to a focus on ensuring that habitatconnectivityismaximised(forexample,throughthe Natura2000 Network). From a purelyacademic perspective, urban ponds representa fascinating array of different water bodytypes,includingbombcraters,swimmingpoolsandfountainsinadditiontogardenponds,parklakes and sustainable drainage systems. Usingdatafromasetof30pondssampledacrosstheCityofOttawainOntario,Canada,Idemonstratethe problems with definitions of “urban” and“natural”: all ponds were impacted by human

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activity,buttovaryingdegreesandindifferentways.Theprinciplecauseofvariationinwaterchemistry between the ponds in the presentstudywaslikelyroadsalt,whichvariedstronglybetween the most urban (a highway drainagepond) to the most natural (a small lake in aProvincialPark). However,biodiversitysurveysshowedthatevenhighly-managedstormwaterretentionpondscanhaveequivalentbiodiversitytoperi-urbanunmanagedponds.Finally,Ishowthatthereexiststhepossibilityforconsiderableoutreach within urban environments andhighlight a new project, the West YorkshirePonds Project (www.wypp.org), which seeksto partner with schools to further knowledgeof freshwaters. This would create a series ofpondsacrosstheCityofLeedswhichcouldbeusedby researchers as anoutdoor laboratoryand by schools as an educational resource,strengthening partnerships between primary,secondaryandtertiaryeducationandprovidingschoolchildrenwithmuch-neededexposuretonatureandecologicalsystems.

Nutrient limitation of phytoplankton growth in arctic lakes

Erika Hogan1, Suzanne McGowan2, N. John Anderson1

1 Department of Geography, Loughborough University, Loughborough, Leicestershire, United Kingdom

2 School of Geography, The University of Nottingham, University Park, Nottingham, United Kingdom

Thereisgrowingevidenceofecologicalchangein arctic lakes. The majority of this evidencecomes from lake sediment records whichsuggest the composition of algal communitieshas changed, and productivity has increasedover thepast150years. Thischange ismostcommonly attributed to climate, in particular,an increase in temperature. However, suchinterpretation often ignores other drivers ofchange, for example, long-range atmosphericnitrogen(N)deposition,whichhasbeenshownto occur over a similar time frame at manysites across the arctic. The region of southwest Greenland is typical of much of thearctic in terms of lake density, precipitationpatterns and vegetation. It also provides aunique opportunity to investigate atmosphericNdepositionasadriverofecologicalchange,

as it has only very recently experiencedrapid, significant 20th century warming whichhas been observed elsewhere in the Arctic.Evidence from Greenland ice core recordsalso indicate that N-NO3- concentration as aresult of atmospheric deposits has increasedover thepastc.150years. There isaclimateand precipitation gradient which exists acrosssouthwestGreenlandfromtheinlandicesheetmargin (continental climate, colder and drier)to the coast (maritime climate, warmer andwetter).Wehypothesisedthattheprecipitationgradientmightalsorepresentagradientinwetatmospheric N deposition, and might resultin a shift from N-to phosphorus (P)- limitationbetween lakes at the ice sheet margin andcoast. Study lakes (n = 21) were situated in3 distinct locations across the region: the icesheet margin, inland at the head of SøndreStrømfjord,andatthecoast.Nutrientlimitationwas investigated 3 times between August2010 and July 2011, allowing both seasonaland regional differences to be explored.Phytoplankton growth was assessed over 14days following invivo fluorescenceofsamplestreated with 1 of 6 nutrient additions: control(noaddition),P (6μMNaH2PO4),NH4

+ (90μMNH4Cl),NO3

-(90μMNaNO3),P+NH4+andP+

NO3- (final concentrations as before). A clear

response tonutrient additionwas found in95% of all bioassays, and of these, co-nutrientlimitationwasmostcommonlyrecorded(70%of cases). Therewasnoevidenceof regionalvariationinnutrientlimitation.However,strongseasonalvariation,withashiftfromP-limitationunder ice to co-limitation during spring andsummerwasrecorded.

Keywords: arctic, nitrogen, nutrient limitation,phytoplankton,phosphorus

Species interactions may inhibit biological recovery in acidified freshwaters

Gareth Jenkins, Queen Mary University of London, United Kingdom

The extensive acidification of fresh watersacross Europe and North America during the20thcenturyledtosystematicandwidespreadloss of species, which in turn fundamentallychanged the structure of resident aquaticcommunities. While attempts to limit or haltthe causative acidifying emissions have been

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successful in a widespread reversal of thechemical consequences of acidification, suchasloweredpHandtoxiccompounds,therehasnotbeenacorrespondingbiological recovery,with evidence for species recolonisationpatchy or lagged at best. Here I presentworkaimedatinvestigatingpotentialecologicalconstraints on this biological recovery, usingmanipulation of both antagonistic direct (suchas predator functional response) and moresubtle indirect (such as apparent competition)speciesinteractions.Byexperimentallyvaryingthe densities of both acid-tolerant and acid-sensitive species in the presence of largeinvertebrate predators, I provide evidencethat the lag in recovery of acidified aquaticcommunities is, at least in part, due tointrinsic resistance to re-colonisation by acid-sensitive species. This resistance is conferredby a combination of both direct and indirectinteractions between predators and prey, andis manifest at various levels of organisation.These findings increase our understanding ofthe drivers which govern the structure andfunctionofecologicalnetworks inresponsetoanimportantclimaticstressor.Thisisespeciallyrelevant given the rapid industrialisation ofdeveloping countries with large populations,such as India and China, which could wellsoonleadtofurtheranthropogenicacidificationon a significant scale. Understanding of howcommunitiesrespondtothisstresswillbevitalif large-scale loss of taxa is to be avoided ormitigated.

Key words: Acidification,recovery,predator-preyinteractions,functionalresponse,climaticstressor

Global change: perspectives from the not so dry Spain

Aitor Larrañaga,Universidad del País Vasco, Bilbao, Spain

Humanity has increased the rate at whichnatural systems are modified and naturalprocesses are being significantly alteredglobally. Although scientists are building upknowledgeonhowtomanagethoseaffections,local authorities have a limited capacity topalliate the effects of some of the issues thattheterm'globalchange'encompasses.Amongthosewefindglobalwarmingthatirremediablywill affect most ecosystems. A recent studycarried out in the north of Spain suggests

that global warming will enhance microbialgrowth, together with the immobilization ofnitrogen to and decomposition of detritus.Moreover,thesamestudysuggeststhatfungaltaxa richness in the coldest streams will bemost affected by the temperature increments.Contrastingly, some other affections includedwithin global change can be locally managed.In this sense, while a great effort has beendedicated to prevent the effects of big dams(>1 hm3) on inland waters (e.g., maintainingecologicalflowsdownstreamorreducingwaterflowdiscontinuitywithfishladders)smalldamshavebeenclassicallyunderstudied.Thetypicallack of management leads to droughts in thereachesbelowthedamthatarerepeatedeverysummer, creating a very significant effect onstreamcommunitiesandfunctions.Ontheotherhand, the replacementofnativevegetationbyplantations inthecatchments(e.g.eucalyptorpine) is proven to alter stream communities,although preserving a native riparian corridorseemstoreducethemagnitudeoftheimpact.In light of these and similar recent studies,future projects should consider three aspectsthatareessentialtounderstandglobalchangeeffects on inland waters. Firstly, they willneed to marry the potential for transferringknowledge to society with the possibility fordevelopingecological theories. Secondly, theyshould enable to rank locally unmanageableand manageable affections to have an ideaof the ability of local actions to cope withglobalchange.Thirdly, theywillneedfocusoninteractionsamongfactorstoidentifythemostsensitiveareasorsituations.

Keywords: Global warming, water regulation,landusechanges,manageabilityoftheaffection,futureprojects

Engineering diversity: the impacts of beavers on aquatic vegetation

Alan Law, University of Stirling, United Kingdom

Human influenced global and local pressuresonfreshwatersystemsareincreasingandshowno sign abating. Therefore it is vital that anyimpacts, pressures or conservation projectsareassessedscientificallyandindependentlyinorder to understand potential related impacts.As an example, the beaver (Castor spp.) isa keystone species where populations areincreasing globally through reintroduction

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projects. They have the potential to create,modifyandalterfreshwaterandriparianhabitatsthrough ecosystem engineering (i.e. dambuilding)andselectiveherbivory.Ourstudiesinamoderatelyproductivepondoveratenyearperioddocumentedhighlyselectiveforagingonmacrophytespeciesresultinginreduceddensitydependant competition with foraged habitatshaving a 3 times greater species richness,increased species diversity and increasedspecies turnover. As no beaver created damsphysicallyalteredthepondhydrology,selectivebeaver grazing alone accounts for significantchangesinhabitatstructure.Studieswerealsoconducted in Sweden whereby changes inmacrophyte and aquatic coloeptera richnessand diversity between beaver created andcontrol wetlands were observed at thelandscape scale. Sites where beaver createddams altered the hydrological regime had asignificantlyhighermacrophyteandcoloepterarichnessanddiversitywithspeciescompositiondiffering between wetland types. Underlyingabiotic environmental variables could notconsistently explain observed differences, yet30%morespecieswereaddedtothelandscapespeciespoolwiththeadditionofthesebeavercreatedhabitats.Thereforereintroductionsandincreasing populations of beavers in thesestudies appear to positively influence thefreshwaterlandscape;thoughourobservationsarenotnecessarilyuniversal.

Keywords; beaver,diversity,richness,macrophytes,coleoptera

Invasive brine and decapod shrimps: what can they tell us about invasion mechanisms in aquatic environments?

Christophe Lejeusne, Estación Biológica de Doñana-CSIC, Sevilla, Spain

Biological invasions are, with climate change,the two major threats to biodiversity andlikely one of the biggest scientific challengefor the 21st century. Each disturbance hasecological and economical effects but theycanalso interact, inducingpotentiallystrongerecological consequences on biodiversity. It isnow quite well admitted that climate changefavoursinvasivespecies,atleastthespreadofthe thermophilic ones. Aquatic environmentssuch as estuaries are particularly sensitiveto biological invasions because of the stronganthropogenic pressures acting on them and

favouring multiple vectors of introduction.However, the mechanisms allowing a speciesto become invasive are still incompletelyunderstood. Various hypotheses have beenproposed (e.g. propagule pressure, enemyrelease hypothesis) but remain insufficient toexplain the mechanisms. Recently, the stresstolerancehypothesisemergedinthecontextofclimatechangeandsupposesthatifaninvasivehasabroaderrangeof temperature tolerancethananative thenan increase in temperatureis likely to have a disproportionately negativeimpactonthenative.Usinganecophysiologicalapproach, we tested this hypothesis. Wedetermined the critical thermal maximum ofbothnativeand invasivecongenericestuarinecrustaceans, and measured their oxygenconsumptionandtheirsurvivalunderdifferentacute thermal stress. In all experiments, theinvasive species performed better than thenative.Wealsocharacterizethetranscriptomesofbothspeciestostudytheirdifferentialgeneexpression facing an acute thermal stress.Molecular functions involved in the stressresponse were very similar between species,but the number of differentially expressedunigenes was ten times higher for the nativecompared to the invasive. All in all, this worktends toconfirm the importanceof the stresstolerancehypothesisasanimportant(butlikelynotunique)mechanismofbiologicalinvasions.

Keywords: biological invasions, estuaries, mechanisms of invasions, stress tolerance hypothesis

Climate change effects on the functioning of inland waters: pervasive influence or minor factor?

Stephen C. Maberly,Lake Ecosystems Group, Centre for Ecology & Hydrology, Lancaster Environment Centre, Lancaster, United Kingdom

Inland waters respond to multiple externalstressors operating at a hierarchy of scalesfrom global (e.g. climate change) to regional(e.g. atmospheric deposition) to local (e.g.nutrient enrichment). These affect differentcomponents of a lake ecosystem and triggera complex series of bottom-up and top-downinternal interactions that control the structureandfunctionofinlandwaters.Therecent(2013)IPCC report clearly demonstrates the globaltrendofchangingclimateandthelinkbetweenthisandgreenhousegasemissions.Forecastsof

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futurechangedependonfutureanthropogenicemissions,buttherewillbesubstantialwarming,withgeographicvariation,andalteredpatternsof precipitation in the coming century. Lakesare very sensitive to weather and climateand detailed analysis of long-term data setsfrom lakes in theEnglishLakeDistrict suchasWindermere,haveshownstrongeffectsoflargescaleprocesseslinkedtothepositionoftheGulfStream,theNorthAtlanticOscillationandRossbyWavebreakingthatalterlakeecology.Somewillcausecoherent interannual responses in lakesacross large geographic regions, others willbe translated differentially depending on lakesensitivitytoaparticularfactorsuchasflushing.Sincearound1990 therehasbeenasignalofwarming water and longer stratification in theEnglish Lake District. There is some evidencethat this has caused phenological changesin the growth of phytoplankton, zooplanktonand fish spawning, with possibilities of trophicmismatch. For some species though, part ofthis change is caused by resource availabilityrather than by a direct temperature effect.Climatechangewillopennichesfornon-nativespecies fromwarmerclimatesandclose themfor species adapted to cooler conditions withconsequences for food web structure anddiet shifts at higher trophic levels. So long asnutrients are available, cyanobacterial bloomsare likely to be favoured by climate changeandlongerandstrongerstratificationhasbeenshowntoexacerbateoxygen-depletionindeepwater. Local management of a particular sitecannotcontrolglobalclimatechange,butsomeeffects can be mitigated by reducing nutrientloads.

Keywords: climate change, long-term data,multiplestressors,phenology,trophicmismatch

From small lakes to global biogeochemical cycles: the influence of mixing processes on phosphorus accumulation and cycling

Eleanor Mackay, Centre for Ecology & Hydrology, Lancaster, United Kingdom

Small lakes (<1km2) are numerically the mostdominant lakes globally and represent a largeproportion of the total area. They are alsoconsidered to be hotspots of biogeochemicalcycling, processing nutrients at higher rates

than larger waterbodies. As a consequence,theyareanimportantcomponentoffreshwatersystems globally. However, our understandingofphysicalmixingprocessesthat interactwithbiogeochemicalactivityhaslargelybeenbasedon observations from large lakes or atypicalevents and the assumption that the sameprocesses apply in small lakes have not beentested.Physicalmixingprocessescontributingto biogeochemical cycling were studied in asmall,eutrophiclakeinthenorthwestofEngland.Typical weak forcing consistent with averagesummertimeweatherconditionsresultedintheupwind advection of buoyant phytoplankton.This isconsistentwithpatterns foundon largelakes where wind forcing is stronger. Shallowwatertransitionzonesbetweentheriverandlakewere shown to be dominated by hydrologicaldilution, although a significant effect of algalup take was found in relation to phosphorusconcentrations,suggestingthatthezonecouldbeahotspot forbiologicalproduction.Modelsof sediment distribution developed for largelakes were a poor descriptor of sedimentphosphorus and organic carbon distribution.Calculationofresuspensionbytheoreticalwind-induced current speeds better reflected thedistribution patterns of these variables. Usingonlythedeepestsiteforestimatesoflakeburialoforganiccarbonandphosphoruscouldleadtoanoverestimateofburialratesby60to100%.Internalphosphorus loadingfromhypolimneticsedimentswasfoundtobestronglyinfluencedby seasonal weather patterns, resultingin large inter-annual variability. This sourceof phosphorus is often poorly quantified inlake phosphorus budgets, yet the variabilityin internal loading found in this study hasimplications for lakemanagementplans in thecontext of changing weather patterns due toclimatechange.

Keywords: Phosphorus,Physicalmixing,Sediment,Transitionzones,EsthwaiteWater

The role of behaviour in biological invasions: interactions between invasive fish and native Iberian species

Kit Magellan, Universitat de Girona, Spain

Theroleofbehaviour inbiological invasions isbecomingincreasingevident.Onefocusisfactors

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that contribute to invasive success, dispersalability and aggressiveness having both beenimplicated. I investigated interactionsbetweenthe highly invasive mosquitofish, Gambusia holbrooki and the native Iberian toothcarp,Aphanius iberus, specifically examining maleGambusia’s ability to differentiate betweenspeciesandsexes.IfoundthatmaleGambusia consistently differentiated between male andfemale heterospecifics but initially failed todistinguish heterospecific females from thoseof their own species. However, they began tolearn to recognise species differences within24hours.Giventhatmostmalematingattemptstowards female Gambusia are unsuccessful,malesmaybeselectedforpersistencedespiterejection. This, together with the lack ofcostly mating displays and nuptial gifts inthe mosquitofish mating system suggests sexrecognition and misdirected mating attemptsmaybelesscostlythanspeciesrecognition.Thedetrimental effects of Gambusia on Aphaniusare therefore not limited to aggression andcompetition, but include sexual harassmentby male Gambusia towards female Aphanius.Selection for persistence and a rapid learningability may be factors explaining the invasivesuccessofG.holbrooki.

Keywords: Behaviouralecology,Ethology,Invasivespecies,Gambusia holbrooki, Aphanius iberus

Freshwater research: key and global or going nowhere?

Brian Moss, University of Liverpool, United Kingdom

In2005,areport,sponsoredbytheFreshwaterBiological Association and Centre for Ecologyand Hydrology, lamented a decline in thenumbers and consequent productivity offreshwaterresearchersintheUK.Thequalityoftheworkwasnotquestioned.But in2007,anarticle by Winfried Lampert, on his retirementfrom the Max Plank Institute for LimnologicalResearch inPlön,Germany,and itsconversiontoaninstituteformolecularecology,lamentedthe quality of European freshwater research.It had become, he alleged, largely practicallyorientated,anddrivenbytheneedsofEuropeanUnionlegislation;itwasnowlargelydescriptive,thoughservedbymoresophisticatedstatistics,butlackinginattentiontofundamentalscience.Washeright?

Freshwater sciences have contributed muchto fundamental ecology, not least RaymondLindeman’s trophic-dynamicconcept, andG.E.Hutchinson’s essay on Santa Rosalia and theniche concept, based on his observations ofcorixids in a Sicilian pond. We understandfreshwater systems well at the fundamentallevel,withastronggroundingintherelationshipsamong catchments and their drainagesystems.Nonetheless, inEuropewemayhavecontributedlessrecentlytothesefundamentalconcepts because our heavily populated,grossly altered, and disconnected landscapesimbueaboundariedattitude.Wethinkintermsof isolated lakes and river reaches, and havenot the opportunity to investigate the greatersystems, such as the linkages uncovered inwestern North America among the ocean,the rivers, and the forests, catalysed by themovements of salmon and the predation ofbears.Likewiseweperhapsavoidopportunitiesto think in termsof thegreatglobal cyclesofwater, carbon and oxygen that regulate thecomposition of our oceans and atmosphere,andregulateourclimate.

ThecompartmentalizationofEurope, reflectedin our thinking, has many consequencesthat support Winfried Lampert’s analysis. Weattempt to conserve aquatic habitats on toosmallascale,with too limitinga legislation,sothat many of our attempts at restoration aredisappointing. We try to reinstate species listsindefinedplacesratherthantorestorethekeyfeatures of nutrient parsimony, characteristicstructure (both physical and biological) andsizeandconnectivity.Inturnthisinfluencesourapproachto therisingproblemofcopingwithclimatechange.Ofcourseweneed to reducecarbonemissionsand findwaysofgeneratingenergybyrenewablemeans,butwealsoneedtoattendtocarbonstorage.Temperatureswillnotfalluntilstoragesaregreaterperannumthanemissions.Insteadofminoractivitiesandevenofwidespreadgeoengineering,withtechniqueseitheryet tobe inventedorwith likelyseriousside effects, we need to restore large areasof biome, with interconnected terrestrial andfreshwater systems that serve tostorecarbonefficiently.Thesemustcomefromareasthatwecurrently use for agriculture (anthromes) thatcurrently occupy three-quarters of the landsurface. We need grand strategies to releasethis landthroughmoreefficient farming,muchreducedfoodwasteandchangeddiets.

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Such grand strategies are alien to thedisconnected thinkingand inadequate trainingofourpoliticalleaders,whoareunlikelytofindsolutions to the nexus of problems of climatechange, over-consumption, developing worldpovertyandexploitation,andbiomedestruction,with its losses of goods and services thatwe face. Change will have to come from thebottom-up,andscientists,especiallyecologicalandenvironmentalscientists,willhavetohaveamajorroleineducatingandleadingthepublicinto thisgranderscale thinking.Buteducationand leadership mean good communication,and beyond widening our compartmentalistthinking, we need to improve our skills vastlyin this respect. Scientific writing has becomemore obscure, more inwardly directed, andincreasingly ineffective in getting importantinformationtowhereitmightbebestused,asithasproliferatedintoaplethoraofnewjournals.Weneedurgentlytoputourownhouseinorder.

Land-use effects on stream food webs and ecosystem services

Daniel Perkins, Imperial College London, Ascot, United Kingdom

Organism size often plays a key role indetermining the structure of ecologicalcommunities because it influences ecologicalprocessesacrossmultiplelevelsoforganization,from individuals and their interactions to foodwebs and ecosystems. For example, CharlesEltonin1927describeda‘pyramidofnumbers’wherethenumericalabun¬danceoforganismsare organised by their size, because ‘theenemy is larger than theanimaluponwhich itpreys’. Understanding how this ‘size structure’might be altered by human impacts is animportantcontemporarychallengeforecology.Freshwater systems (e.g. streams and rivers)might particularly susceptible in this respect,becausethesesystemstendtobestronglysizestructuredandhavethepotentialtobegreatlyinfluenced by changes in adjacent land-use(e.g.changes intypeandamountofterrestrialsubsides entering systems). I compiled a datasetcomprisingapproximately60,000individualsizemeasurementsofbenthicdiatoms,macro-invertebratesandfishsampledfrom36streamsacrosstheUKandtheirtrophicinteractions(i.e.whoeatswhom).Thisdatasetwasusedtotestfortheinfluenceofriparianland-use(deciduouswoodland,coniferouswoodlandandmoorland)

on food web and community structure. I findthat stream communities from deciduouswoodland sites are less size structured thanwewouldpredict (frommetabolic theory) andsupportgreaterbiomassathighertrophiclevelsthanstreamsinconiferousormoorlandriparianzones. This is driven by a greater amount ofterrestrial subsidies (in the form of leaf litter)and greater proportion of detritivore links inthesesites,whichincreasestheflowofenergyto higher trophic levels. These results haveimportant implications for predicting changesinecosystemservicessuchasthoserelatedtofisheries (fish standing stocks and production)and regulation of detrital processes (e.g. leaflitter decomposition) under different land-usechangescenarios.

Keywords: Bodysize,foodwebs,metabolicscaling,terrestrialsubsidies,ecosystemservices.

Inland waters as model systems to study metacommunities

Isabel Reche, Departamento de Ecología, Facultad de Ciencias, Universidad de Granada, Spain

Since the Forbes seminal article “The lakeas a microcosm” (1887), most limnology wasfocusedonwithin-lakeprocessestounderstandplankton dynamics. More recently, lakes arebeen considered in a landscape contextinteracting with the terrestrial and humanprocesses, recognizing finally its influenceat temporal and spatial scale. This newapproach allows considering lakes as islands,eventually connected by organisms’ dispersal,establishing a metacommunity. Therefore,besides competition and predation as within-lakes processes, species immigration can beaffecting plankton communities among lakes.Nestedness analysis emerges as a useful tooltodetermine thebalancebetweenwithin-andamong-lakes processes structuring planktonassemblages.

In this seminar, nestedness analysis wasproposed to explore the influence of diverselandscapes on microbial metacommunities.Nestedness measures the degree to whichspecies assemblages are representativesubsets of larger assemblages. Microbialecologists, since the advent of DNA-based

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molecular technologies, have started to testgeneral ecological patterns and use thediverse and well-developed metrics providedby the macroecology. We determined thenestedness of bacterial assemblages intwelve metacommunities from well-contrasted(boreal, alpine, temperate) landscapes andconnectivity level (presence/absence of inletsand geographical distances). We obtainednestednessmetricsusingthesofwaresprovidedby Ulrich (2006) and Almeida-Neto and Ulrich(2011). The matrix temperature ranged from24.6 to 34.5 ºC (0º represents an entirelynested assemblage and 100ºC a completelydisordered assemblage) and the NODF indexrangedfrom30.8to76.2.Thecomparisonwithnullmodelsindicatedthatmostofthebacterialmetacommunities analyzed were significantlynested, irrespectivelyofthepresenceof inletsconnections, as it was expected for the highdispersal availability of microorganisms. Highlyconnectedlakesshowedahigherproportionofspeciesfromthegeneralpool(%fillwashigher)with low idiosyncratic species and the masseffect(immigration)appearstobethedominantprocess. By contrast, scattered lakes showedhigher idiosyncratic species likely driven byspecies sorting within lakes. Therefore, thelandscape structurecan significantly influencemicrobialassemblagesinlakesandlakesaveryusefulmodeltotestmetacommunityhypothesis.

Studying feeding rate in Artemia provide insights on the competitive superiority of the exotic A. franciscana and its potential impact in hypersaline ecosystems

Marta Sánchez, Estación Biológica de Doñana-CSIC, Sevilla, Spain

Oneofthemostdramaticcasesofbiodiversityloss in hypersaline ecosystems in theMediterranean Region and worldwide is theinvasion of the North American brine shrimpArtemia franciscana, which is leading to theextinction to most native A. salina and A. parthenogenetica populations. The successof A. franciscana has been attributedto its higher fitness combined with a lowregulation by parasites which highly impactnative taxa (decreased fertility and increasedpredation). Artemia is a keystone species inhypersaline ecosystems; it is the dominantmacrozooplankton,servingasthemainpreyof

birds andaffectingphytoplanktondensity andcommunity structure through its filter feedingactivity.Inthisstudywecomparefeedingratesbetween native A. parthenogenetica and theinvasive A. franciscana, as well as the effecton feeding rate of the two most prevalentavian cestode species in A. parthenogenetica.Grazing experiments showed a strongdifference in the grazing rates of native andinvasiveArtemia,withA. franciscana exhibitingsignificantly higher values. Feeding rate washigher in females compared to males. Thegrazing rates also clearly differed betweeninfected and uninfected A. parthenogenetica,with important differences between particularcestode species. F. liguloides (adults infectingflamingos) significantly reduced feedingrate in its host, while Confluaria podicipina(adults infecting Grebes) induced a slight butmarginally insignificant increase in filtrationrates. We conclude that higher filtration ratesinA. franciscanacomparedwithnativespeciesmay add an additional competitive advantagetotheinvader,whichwouldbeenhancedbytheeffectofcestodeparasitesonthefeedingrateof infected native Artemia. At the ecosystemlevel,theintroductionofamoreefficientgrazermay destabilize the phytoplankton communityand affect hypersaline ecosystem functioningthrougharangeofdirectandindirectecologicaleffects.

Quantifying the effects of grazing on aquatic ecosystems

Kevin A. Wood, School of Applied Sciences, Bournemouth University, United Kingdom

Foraging by primary consumers on primaryproducers is a fundamental biotic processin nature. The outcomes of such plant-herbivoreinteractionscontrolprimaryproducerabundanceandregulatetheflowofenergyandnutrientsbetweenprimaryproducersandhighertrophic levels. Thus understanding how plant-herbivore interactions are regulated is criticaltoourunderstandingof,andabilitytomanageecosystem structure, functioning and serviceprovision. Despite the recent proliferation ofsmall-scalestudiesontheeffectsofherbivoreson aquatic plant abundance, ecologists lackan understanding of the factors which controlconsumer regulation of vascular plants acrossaquatic ecosystems. I conducted a globalmeta-analysis of the factors influencing the

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outcome of plant-herbivore interactions usinga dataset comprised of 292 values from 152studies.Iexaminedeightfactors,identifiedfromprevioussmall-scalestudies:herbivorebiomassdensity, herbivore taxonomic identity, whetherherbivores were native or non-native, habitattype, latitude,phaseoftheplantgrowthcycle,size of experimental area, and study length. Ishowedthatchangesinplantabundancewereaplasticfunctionoftwoaspectsoftheherbivoreassemblage: density and taxonomic identity.Plant abundance declined with increasedherbivore density, with plants eliminated athigh densities. I report substantial between-taxa differences in herbivore effects on plantabundance,withbirdsandinsectshavingleasteffect and molluscs and echinoderms havingthegreatesteffectforagivenherbivoredensity.I suggest that such between-taxa differencesare linked to differences in herbivore foragingecology and individual dispersal ability. Incontrast,noeffectsofwhetherherbivoreswerenativeornon-native,habitattype,latitude,phaseof theplantgrowthcycle,sizeofexperimentalarea, or study length were detected. My talkhighlights the key roles that two aspects ofthe herbivore assemblage, herbivore densityand taxonomic identity, play in regulating theoutcomesofplant-herbivoreinteractionsacrossaquaticecosystems.

Keywords: Grazing; Herbivores; Macroecology; Macrophytes; Plants

Landscape-scale conservation of aquatic biodiversity and the contribution of different habitats

Nigel Willby, University of Stirling, United Kingdom

Landscape-scale thinking, including thecreation of interconnected and more resilientnetworks of habitats, is the new mantra ofnature conservation bodies, and is heraldedas the means to promote collaboration,improve adaptation to climate-change andhalt biodiversity decline. However, freshwaterecologiststraditionallypigeon-holehabitatsandusehabitat-specificsamplingprotocolsmeaningthat the relative value of different habitatsto regional biodiversity is poorly understoodandpotentialinteractionsbetweenhabitatsare

largelyignored.Hencetheknowledgeavailableto underpin landscape scale conservation islikelytofallshortofrequirements.Connectivityisaquintessentialfeatureoffreshwatersystemsbut the various dimensions of connectivity,vertical, lateral and longitudinal, and thelinkagesbetweenpopulationshavebeenhighlydisrupted by human activities. An improvedunderstanding of the comparative biodiversityof different aquatic habitats and the linkageswithinandbetween thesehabitats is thereforeimportant to underpin conservation strategiesand catchment scale planning. This theme isdevelopedbyconsideringdifferent aspectsofplantdiversity-localrichness,rarity,invisibility,turnover and the total species pool - acrossa range of aquatic habitats that coexist inlowland landscapes, toassesshow largescalediversity and resilience depends on mosaicsof interconnected habitats. Hydrologicallyconnected backwaters (a habitat ignored bymostconventionalmonitoringschemes)hadthehighestlocalrichnessbuttheirspeciespoolwassimilartopondsandlakesduetolowerturnoverbetweensites.All habitats – includingmediumand large rivers - contributed to the regionalspecies pool, but the relationship betweenbiologicalsimilarityandspatialproximityofsitesvaried between habitats. Arresting biodiversityloss and improving the success of costly site-specific restoration projects requires thinkingat far larger scales, including connecting orenlarginglowprioritysites,andlookingbeyondthe traditional confines of discrete habitats; acentury of experience shows that instinctivelyringfencingthecathedralsofnaturefromtheirsurroundingsisnotenough.

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EVALUATION QUESTIONNAIRE

2. The discussion timing was right

3. The length of the seminar was correct

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4. The mix of participants was right

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7. The food was good



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Numberofparticipants 30

Numberofquestionnairesreceived 25

Percentage83%

Results of Event Evaluation Questionnaires

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GENERAL COMMENTS

Thankyouverymuch fororganising thework-shop. I felt Igotagreatdealoutofattending.(ErikaHogan)

Ihadanexcellenttime,andtheworkshopwasextremelyproductive(Alan Law)

Very enjoyable and well organised meeting– helped by an excellent location. (Stephen Maberly)

Overall it was a great forum to discover moreabouttheresearchofotherpeopleinthefieldand make new contacts and connections thatmaybeofuseinthefuture. (Eleanor Mackay)

Thank you for organising an excellent work-shop. We all found the workshop very useful.(Kevin Wood)

Wespentalotoftimesittingthroughpresenta-tionsbuttherewaslesstimeforformaldiscus-sions of collaborations some “special interestgroups”couldhavebeenusefultohelpthis.Onthe whole, an excellent and highly worthwhilemeeting.(Christopher Hassall)

ThereisnothingIcanthinkofthatcanimprovetheexperience.(Aitor Larrañaga)

Thank you again for organising such a greatworkshop.Ihadabrillianttime!(Gareth Jenkins)

ACkNOWLEDGEMENTS

We would like to thank the Consejo Superiorde Investigaciones Científicas and the BritishCouncil for organizing this excellent and thor-oughlyenjoyablescientificmeeting.Theeventhasprovidedmanyexcellentopportunities fordialogue and discussion, whilst demonstratingthestrengthandvitalityofouryoungscientists.We would like to emphasize in particular thehardworkandkindnessofBelenForteaoftheBritish Council. Her careful continued supportandefficiencymade the successof thework-shopinDoñanapossible.TheEBDdirectorJuanJoséNegroBalmasedaalsoprovidedessentialsupportbeforeandduringtheworkshop.AtthePalaciodeDoñana, Fernando IbáñezandPilarBayónprovidedcontinuousandessentiallogis-ticalsupport.RafaelMartínGuitartalsohelpedwithpreparations.Withtheirhelp,theworkshopwasaverypleasantexperienceforthepartici-pants,aswellasbeingverystimulatingfromthescientificpointofview.

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www.britishcouncil.es www.csic.eswww.britishcouncil.es www.csic.es

ScienceCOORDINATORS:

Brian MossUniversity of LiverpooL

andy J. Green estación BioLógica de doñana (seviLLa)

“The ecology of inland waters”

EsTación Biológica dE doñana (HuElva), 13-17 ocToBEr 2013

British CouncilEducation and Society

Paseo del General Martínez Campos, 3128010 Madrid. Spain

CSICConsejo Superior de Investigaciones CientíficasVicepresidencia de Relaciones Internacionales

Calle Serrano, 11728006 Madrid. Spain

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“the ecology of inland waters”...ecology in europe. it was perceived (by terrestrial and marine...

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