Abstract
C:N:P ratios of epilithic periphyton were measured in littoral zones (25 stations), inflow rivers (30 stations), and lagoons (23 stations) of Lake Biwa to evaluate the nutrient status of freshwater epilithic periphyton. Dissolved inorganic nitrogen (DIN) and phosphorus (DIP) in surface waters at respective station were also determined. The results of DIN:DIP ratios in surface water suggested that the growth of periphyton was limited by phosphorus at most stations (71 stations of all stations). The results of C:N:P ratios of periphyton suggested that the growth of periphyton was not limited by each nutrient concentration at most stations (69 stations of all stations). The present study seems that C:N:P ratios of periphyton were influenced not only by DIN:DIP ratios in water, but also by water temperature, light intensity, water current, algal species, and so on.
