TRACE ELEMENT KINETICS IN CONTAMINATED POSIDONIA OCEANICA MEADOW J. Richir, N. Luy, G. Lepoint, A. Alvera Azcarate, R. Biondo, S. Gobert Essaouira

Mediterranean submitted to anthropic pressures Introduction INTRODUCTIONINTRODUCTION bioindicator : Posidonia oceanica - monitoring of coastal ecosystem pollution; - representative accumulation; - pollutant biologically accessible. pollution trace elements (TEs) TECdPbCuZnCrFeNi # ref TEAsAgCoMnAlBiVMo # ref Luy et al. (2012)

Mediterranean submitted to anthropic pressures Introduction INTRODUCTIONINTRODUCTION bioindicators : Posidonia oceanica pollution trace elements (TEs) TEs uptake and loss kinetics of P. oceanica contaminated in their natural environment? e.g.: Ledent (1992); Warnau et al. (1996)

Mediterranean submitted to anthropic pressures Introduction INTRODUCTIONINTRODUCTION bioindicators : Posidonia oceanica pollution trace elements (TEs) TEs uptake and loss kinetics of P. oceanica contaminated in their natural environment? Objectives: To study TEs kinetics and tissue compartmentalization of P. ocenica contaminated in situ at 2 experimental levels: - moderate: 21x Calvi SW conc.; 4x world ocean mean conc. - acute: 151x Calvi SW conc.; 31x world ocean mean conc. e.g.: Ledent (1992); Warnau et al. (1996)

In situ experimental contaminations MATERIAL - METHODS

MATERIAL-METHODSMATERIAL-METHODS Contamination at moderate levels 5 days of contamination in June 2009; 410L bell-shaped mesocosm; Contamination every 12 hours (9am-9pm); 15 days of decontamination.

MATERIAL-METHODSMATERIAL-METHODS Contamination at moderate levels

MATERIAL-METHODSMATERIAL-METHODS Contamination at acute levels 24h00 of contamination in June 2009; 54L rectangular-box mesocosm; 5 contaminations, 1 every 3 hours (9am-9pm); 15 days of decontamination

Posidonia oceanica (A) shoot of leaves on a plagiotropic rhizome (Rz); (B, C) adult leaves (AL); (D) intermediate leaf (IL); (E) juvenile leaf. Libes and Boudouresque,1987 plagiotropic shoot orthotropic shoot rhizome blade roots MATERIAL-METHODSMATERIAL-METHODS limb ligula leaf base (petiole) ED CB A root leaf base stipule scale rhizome

RESULTSRESULTS Ag moderate conta.: kinetics

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RESULTSRESULTS

RESULTSRESULTS

RESULTSRESULTS Ag moderate conta.: compartmentalization

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RESULTSRESULTS Ag moderate conta.: kinetics

RESULTSRESULTS Ag acute conta.: kinetics

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RESULTSRESULTS

RESULTSRESULTS Ag acute conta.: compartmentalization

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RESULTSRESULTS Ag acute conta.: kinetics

CONCLUSIONCONCLUSION Conclusion P. oceanica takes up TEs from the beginning of experiments; Moderate contamination design are preferred; Once contaminations end, TE concentrations rapidly decrease; Leaves exhibited different uptake kinetics: the younger growing leaves forming new tissues incorporated chemicals more rapidly than the older senescent leaves; Rhizomes did not show any clear trend. P. oceanica is a sensitive sentinel to delineate punctual pollutions similar to what might be measured in contaminated Mediterranean waters routine use in regularly scheduled monitoring programs.

QUESTIONSQUESTIONS Thank you for your attention

RESULTSRESULTS Cu moderate conta.: kinetics

RESULTSRESULTS Cu moderate conta.: compartmentalization

RESULTSRESULTS Cu moderate conta.: kinetics

RESULTSRESULTS Cu acute conta.: kinetics

RESULTSRESULTS Cu acute conta.: compartmentalization

RESULTSRESULTS Cu acute conta.: kinetics

RESULTSRESULTS Fe moderate conta.: kinetics

RESULTSRESULTS Fe moderate conta.: compartmentalization

RESULTSRESULTS Fe moderate conta.: kinetics

RESULTSRESULTS Fe acute conta.: kinetics

RESULTSRESULTS Fe acute conta.: compartmentalization

RESULTSRESULTS Fe acute conta.: kinetics

Analytical steps: homogeneous sample acidic digestion in a microwave oven measures :  inductively coupled plasma mass spectrometer MATERIAL-METHODSMATERIAL-METHODS Laboratory analyses Ethos D ELAN DRCII