FN Archimer Export Format
PT J
TI Two decades of oligotrophication: Evidence for a phytoplankton community shift in the coastal lagoon of Thau (Mediterranean Sea, France)
BT 
AF Derolez, Valerie
   Soudant, Dominique
   Malet, Nathalie
   Chiantella, Claude
   Richard, Marion
   Abadie, Eric
   Aliaume, Catherine
   Bec, Beatrice
AS 1:1;2:2;3:3;4:1;5:1;6:1;7:4;8:4;
FF 1:PDG-ODE-LITTORAL-LERLR;2:PDG-ODE-VIGIES;3:PDG-ODE-LITTORAL-LERPAC;4:PDG-ODE-LITTORAL-LERLR;5:PDG-ODE-LITTORAL-LERLR;6:PDG-ODE-LITTORAL-LERLR;7:;8:;
C1 MARBEC (Univ. Montpellier, CNRS, IRD, Ifremer), 34203, Sète cedex, France
   Ifremer, VIGIES. 44311, Nantes Cedex 03, France
   Ifremer, LERPAC/CO, 20600, Bastia, France
   MARBEC (Univ. Montpellier, CNRS, IRD, Ifremer), 34095, Montpellier, France
C2 IFREMER, FRANCE
   IFREMER, FRANCE
   IFREMER, FRANCE
   UNIV MONTPELLIER, FRANCE
SI SETE
   NANTES
   CORSE
SE PDG-ODE-LITTORAL-LERLR
   PDG-ODE-VIGIES
   PDG-ODE-LITTORAL-LERPAC
UM MARBEC
IN WOS Ifremer UPR
   WOS Ifremer UMR
   copubli-france
   copubli-univ-france
IF 2.929
TC 35
UR https://archimer.ifremer.fr/doc/00629/74063/73514.pdf
LA English
DT Article
DE ;Eutrophication;Oligotrophication;Nutrients;Recovery;Phytoplankton community shift;Mediterranean coastal lagoon
AB Mediterranean costal lagoons have been exposed to anthropic eutrophication for decades. Thau lagoon is one of the largest among them and provides many ecosystem services including shellfish farming. Considerable efforts were made between the 1970s and the late 2000s to improve the wastewater treatment systems in the lagoon watershed. A decrease in nutrient inputs to Thau lagoon was subsequently observed, evidence for the start of a recovery process in Thau lagoon, following oligotrophication. This decrease has significant consequences for ecosystem communities, above all primary producers. In our study, we characterised and quantified long-term changes by analysing long monitoring time-series (1998-2016) of phytoplankton biomass, abundance and composition of the taxa, nutrients and climate conditions, using univariate and multivariate statistics. Our results revealed that two decades of mitigation actions in the Thau lagoon watershed have led to a significant progressive reduction in nutrient concentrations and in phytoplankton biomass (-60%), associated with a decrease in diatom abundance (-66%), particularly affecting Skeletonema spp. The changes were associated with a community shift characterised by a shift in phytoplankton taxonomic dominance from Skeletonema-Chaetoceros to Chaetoceros-Pseudo-nitzschia. The median proportion of dinoflagellates relative to diatoms increased, although the total dinoflagellate abundance did not change significantly. We hypothesise that the shift in phytoplankton communities is the result of the mixed effects of the reduction in nutrient inputs and of climatic-related variables. Finally, we present a conceptual scheme of the main drivers of phytoplankton community structure to clarify the ecosystem functioning of a Mediterranean lagoon used for shellfish farming, under oligotrophication and climate change.
PY 2020
PD AUG
SO Estuarine Coastal And Shelf Science
SN 0272-7714
PU Elsevier BV
VL 241
UT 000539292700003
DI 10.1016/j.ecss.2020.106810
ID 74063
ER

EF