TABLE 1.

Characteristics of the six sampling sites

Characteristic	Result from:
	Grangent Reservoir	Villerest Reservoir	Cuzieu (Loire River)	Feurs (Loire River)	Sables Pond	Place Pond
Minimum Secchi disk depth (m)	1.0	0.7	NDa	ND	0	0.2
Chlorophyll a concn (mg m−3)
Annual mean	11.0	20.5	4.8	16.0	73.2	52.4
Maximum	47.6	62.9	9.8	35.2	149.6	87.8
Maximum temp (°C)	25.2	27	28.2	28.3	26.6	27.7
Total phosphorus (mean annual concn of inflow [mg liter−1])	0.04	0.08	0.09	0.09	2.37	1.45
Proportion (%) of M. aeruginosa in:
Phytoplankton	86	ND	ND	ND	51	42
Cyanobacteria	94	ND	ND	ND	81	81
Trophic statusb	Eutrophic	Eutrophic			Hypereutrophic	Hypereutrophic

^aND, not determined.

^bFrom OCDE (31a).