連続砂防堰堤を持つ河川の水温形成に関する研究

抄録

In previous researches (e.g.: Nakano et al, 1996), it is estimated that habitat for cold water fish will be decreasing in Hokkaido area, Japan, if water temperature go up several degrees by global warming. In summer, habitat for Siretoko Peninsula (20 degree is limit temperature) comes severer in daytime by radiation in Siretoko Peninsula, and Sabo dam series is suspected as a factor further heating.

In this study, under an assumption that dam makes wide, shallow, and slow flow area and they make further heating effects by radiation/sensitive heat flux, field investigations on micro meteorology, temporal/spatial water temperature change and flow field are done in two domains with/without dam series in the Kanayama River. Furthermore small experiment also done to know heal flux magnitude of dam fall’s heating effect

Result shows that: (1) radiation’s effect is larger in dam series domain than another. (2) This effects are estimated by flow field with wide water surface and slow velocity made by river bed shape with flat dam.

(3) At dam falls, heating effect is negligible or cooling effect is larger by latent heat. By further research, explanation of heating effects by falls taking warm air at pools is expected.