Yuzo Yamamoto,^1,2 Hideaki Shibata,^3,4 Hiroshi Ueda<sup>1,4,*

1</sup>1Aquatic Bioresources and Ecosystem Research Group, Field Science Center for the Northern Biosphere,
²†Present address: Demonstration Laboratory, Marine Ecology Research Institute, 4-7-17 Arahama, Kashi
³2Watershed Function Research Group, Field Science Center for the Northern Biosphere, Hokkaido Univer
⁴3Division of Biosphere Science, Graduate School of Environmental Science, Hokkaido University, North

^*Corresponding author. Tel. :+81-11-706-2598; Fax : +81-11-706-2598; E-mail: hueda@fsc.hokudai.ac.jp