1. Forest Research Institute Hokkaido Research Organization Bibai Japan
2. Aqua Restoration Research Center Public Works Research Institute Kakamigahara Japan
3. Arctic Research Center Hokkaido University Sapporo Japan
4. Doto Station, Forestry Research Institute Hokkaido Research Organization Shintoku Japan
5. Faculty of Environmental Earth Science Hokkaido University Sapporo Japan
6. Department of Forest Science, Graduate School of Agriculture Hokkaido University Sapporo Japan