Pollution Load and Water Quality Conditions of Lake Onogawa

Abstract

Field observation on how the characteristics of pollution load and the conditions of water quality of mountainous Lake Onogawa change as time progresses is investigated. The process of nutrient release from bottom deposit is discussed from the data on batch test of and field observation. In the hypolimnion, nitrogen metabolism is controlled by the process of nutrient elution and'diffusion process. In the epliminion, the water quality of the lake is between olig- and mesotrophic condition because the lake is used for hydropower generation.