Effect of copper sulphate treatment on natural phytoplanktonic communities.
Copper sulphate treatment is widely used as a global and empirical method to remove or control phytoplankton blooms without precise description of the impact on phytoplanktonic populations. The effects of two copper sulphate treatments on natural phytoplanktonic communities sampled in the spring and summer seasons, were assessed by indoor mesocosm experiments. The initial copper-complexing capacity of each water sample was evaluated before each treatment. The copper concentrations applied were 80 microg l(-1) and 160 microg l(-1) of copper, below and above the water complexation capacity, respectively. The phytoplanktonic biomass recovered within a few days after treatment. The highest copper concentration, which generated a highly toxic environment, caused a global decrease in phytoplankton diversity, and led to the development and dominance of nanophytoplanktonic Chlorophyceae. In mesocosms treated with 80 microg l(-1) of copper, the effect on phytoplanktonic community size-class structure and composition was dependent on seasonal variation. This could be related to differences in community composition, and thus to species sensitivity to copper and to differences in copper bioavailability between spring and summer. Both treatments significantly affected cyanobacterial biomass and caused changes in the size-class structure and composition of phytoplanktonic communities which may imply modifications of the ecosystem structure and function.
Le Jeune
Anne-Hélène
AH
UMR CNRS 6023, Laboratoire de Biologie des Protistes, Université Clermont-Ferrand II, 24, Avenue des Landais, 63177 Aubière Cedex, France.
Charpin
Marie
M
Deluchat
Véronique
V
Briand
Jean-François
JF
Lenain
Jean-François
JF
Baudu
Michel
M
Amblard
Christian
C
D000818:Animals; D044822:Biodiversity; D018533:Biomass; D019327:Copper Sulfate / Q000032:analysis / Q000633:toxicity*; D000458:Cyanobacteria / Q000187:drug effects* / Q000302:isolation & purification; D004141:Dinoflagellida / Q000187:drug effects* / Q000302:isolation & purification; D056890:Eukaryota / Q000187:drug effects* / Q000302:isolation & purification; D010839:Phytoplankton / Q000187:drug effects*; D012621:Seasons; D013997:Time Factors
D019327:Copper Sulfate