Abstract
This paper proposes a method to calculate water and nutrient flux between bays and major basins of large lakes in stratification period, called isotherm surface method (ISM). The data set used for this study involves water temperature time series from a fine-scale profiler, water currents from an acoustic Doppler current profiler (ADCP) and nutrient concentration distribution data by water samples of several vertical layers during 4 year-48 hour continual observations in Shiozu bay of Lake Biwa. A good agreement between the measurement and the flux by the ISM indicates that this method is appropriate. Subsequent analysis shows that this method could be used widely for estimating flux between bays and major basins of large lakes in stratification period if the Wedderburn Number is more than one.
