1. Research Center for Environmental Quality Management, Kyoto University, Otsu, Shiga, Japan
2. Lake Biwa Branch Office, National Institute for Environmental Studies, Otsu, Shiga, Japan
3. Department of Civil and Environmental Engineering, Ritsumeikan University, Kusatsu, Japan
4. Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, Japan
5. Regional Environment Conservation Division, National Institute for Environmental Studies, Tsukuba, Ibaraki, Japan
6. Graduate School of Agriculture, Kyoto University, Kitashirakawa-Oiwake, Sakyo-ku, Kyoto, Japan