Secchi disk in Lake Santo Parmense (2007-2010)

Water transparency was measured at the point of maximum depth of the lake by means of a Secchi disk. (Spatial Scale Description: Water samples were collected at the point of maximum depth of the lake by means of a Ruttner bottle. Samples were collected at the following depths: 0, -5 m, -10 m, -15 m, bottom. Samples were kept refrigerated and transported to the laboratory where dissolved reactive phosphorus was determined spectrophotometrically following APHA, AWWA, WPCF (1971). In 1972 samples were collected only on one date in september. In 1973 samples were collected monthly from january to april (twice in february).)