WATER QUALITY CHARACTERISTICS IN LAKE TATARANUMA FROM FIELD SURVEY

Abstract

 Lake Tataranuma in Gunma has been suffering from a deteriorating environment for aquatic plants and animals due to the development of the area and the increase in polluted wastewater since around the period of rapid economic growth. In many cases, water pollution in lakes is caused by a variety of factors, and it is necessary to make sure of the relationship between the phenomena and the factors. In this study, we investigated the spatiotemporal characteristics of water quality in Lake Tataranuma based on field surveys conducted four times a year. The results showed that thermal stratification in the central part of Lake Tataranuma, which has a large water depth, during the summer season. The vertical profiles of DO, pH and chlorophyll fluorescence in summer were related to thermal stratification.