Céline LAFABRIEOlivier PRINGAULTAsma SAKKA HLAILIChristophe LEBOULANGER Rutger DE WIT

Anthropization of Mediterranean lagoon ecosystems:

impact of chemical contaminationon the functioning and diversity

of first pelagic trophic levels

Final Workshop of the START/MaghLAG ProjectBizerte (Tunisia) 25-27 June 2012

Goods and services- High productivity- Nursery and feeding zones- Biodiversity hotspots, etc.

Coastal lagoons

High anthropic pressures

Urbanization AgricultureIndustries

Chemical contamination

Þ Threatened/endangered ecosystems2

© OzCoasts (G

eoscience Australia) 2

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High importance in geochemical cycles

Fundamental roles in ecosystems functioning(O2 production, organic matter transfer…)

Sensibility to xenobiotics

Base of food webs → Control of upper trophic levels (“bottom-up” regulation)

Phytoplankton

3

Photosynthetic pelagic

organisms↓

Play a major part in lagoon ecosystems

Aim of the study

To determine effects of resuspended contaminated sediment on phytoplankton diversity and functioning

To evaluate the selection pressure that chemical contamination may exert on phytoplankton communities

Original and innovative approachPluridisciplinarity (chemistry/biology) – Multicontamination

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Impact of chemical contaminationon natural phytoplankton communities

Interesting site to evaluate phytoplancton

sensibility to contaminants

COMETE, 2005

High chemical contamination

pressures

Menzel Abderahman

Bizerte

Menzel Bourguiba

Urban areas and main chemical releases

PolycyclicAromaticHydrocarbons (PAH),Tracemetals

Pesticides

Trace metals

N

1 km

Size = 11 x 13 kmArea = 15 000 haMean depth = 8 mMax. depth = 12 m

Bizerte lagoon

Mediterranean Sea

Tunisia

Study sites

CS

L

M

5

Primary production

Growth

Specific diversity

Physiological activities

Experimental protocol

In situ experiments

Laboratoryanalyses 2 x 5-days investigations

Contaminated sediment elutriate

(prepared from site CS sediment and water)

Phytoplancton

exposition

Phytoplancton(from site L and site M)

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Þ Comparisons of « control microcosms » with « contaminated microcosms »

First results

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Nutrients seem to strongly influence responses of phytoplankton exposed to contaminated sediment elutriate, stimulating growth and counterbalancing the possible harmful effects of contaminants

0 24 48 72 960123456789

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Control Exposed to elutriate

Time (h)

PN (µ

mol

O2/

L/h)

Net production

0 24 48 72 960

2

4

6

8

10Contrôle Exposed to elutriate

Time (h)

Resp

irati

on (µ

µmol

O2/

L/h)

Respiration

UMR 5119 ECOSYM « Écologie des systèmes marins côtiers » (Montpellier) - M. Troussellier et M. Bouvy

RéseauxPlancton (RESEAUX)

Populations planctoniques (DROP)

Algues toxiques (ETDA)

Benthos / Pelagos (BIP)

PHYTOPLANKTON

COLLABORATION

JEAI ECOBIZ (2012-14)Ecology of south-mediterranean coastal lagoons

Impact of anthropization on the diversity and functioning of first pelagic trophic levels in the Bizerte lagoon

Resp.: M.N. Daly Yahia (FSB); Cor. AIRD: O. Pringault (IRD, ECOSYM)

FSB (Faculté des Sciences de Bizerte, Tunisie)

Project insertion

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Tunisie

France

Espagne

Italie

Algérie

Maroc

Libye Egypte

TurquieGrèce

Chypre

SlovénieCroatie

Boznie-Herz.

Monténégro

Albanie

Malte

Syrie

Liban

IsraëlTerritoires

palestiniens

Þ North-South comparisons of coastal lagoons within the Mediterranean basin

Perspectives

9

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Réseau d’Etude des Ecosystèmes des Eaux de Transition

Founded in 2006

Ambition to network people working in France (including overseas) on coastal ecosystems, coastal lagoons, coral reef lagoons, estuaries => “Transitional Waters”

Web-site: www.reeet.univ-montp2.fr

Major activities so far

Budgets LOICZ (Land-Ocean Interactions in the Coastal Zone) working group continues to collaborate with lagoon managers

Organization of the 4th European Conference on Coastal Lagoon Research (=> EuroLag: European Coastal lagoon symposium)

REEET - France

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14-18 December 2009, in Montpellier

319 participants from 21 countries

3 special issues being prepared: Hydrobiologia, Estuarine Coastal and Shelf Science, and Transitional Waters Bulletin

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1313

14

20 June - Hydrobiologia SI, 7 out of 9 published on-line

20 June – SI ECSS15 out of 16 published on-line

شكراThanks