“…At each plot, depth-integrated subsamples were taken from four random points using a 45 mm internal diameter clear plastic tube, and combined for analysis of nutrients, chlorophyll a and turbidity. Standard analytical methods were used to determine total phosphorus and total nitrogen (Valderrama, 1981), filterable reactive phosphorus (Johnson, 1982), nitrate plus nitrite (Johnson, 1983), ammonium-nitrogen (Switala, 1993), and chlorophyll a (APHA, 1995) as an indicator of phytoplankton biomass. Turbidity was analysed in situ (Hach 2100P Turbidimeter).…”