Water chemistry and biology in a shallow lake (Lake Pamvotis - Greece). Present state and perspectives

Lake Pamvotis is a shallow lake, located in NW Greece, which during last decades has influenced by a lot of man-made impacts such as sewage discharge, water level fluctuation, e.t.c. Water quality for physicochemical and biological parameters was monitored seasonally in five sampling-stations from April 1998 to March 1999. Lake Pamvotis is an eutrophic ecosystem which has been influenced by the nutrients input, rates of nutrient cycling and plankton-fish dynamics. According to the nitrogen: phosphorus ratio, the limiting factor is phosphorous during spring while a nitrogen limitation is switched on during the warm season. Restoration management strategy requires reduction of external organic load, control of non-point pollution from the surrounding agricultural area and establishment of biomanipulation techniques.