木津川植生砂州における伏流水輸送と窒素動態

抄録

Recently it is recognized that subsurface water zone under river sandbars has functions of habitat for benthos and microorganism/microbe living in substrate, and that some of those remove materials from the water or change physicochemical characteristics. Sandbar formed in channel is the basis for the subsurface process in which surface flow pass through the bar, and the bar serves as a place to purify water or cycle nutrients in the river environment. In the present research, behavior of nitrogen as a nutrient is studied. The behavior of subsurface flow and changes in water quality are examined with a field investigation. The evaluation of water quality transformation functions in the subsurface process in vegetated sandbar was attempted. Results show that vegetation cover decreases disturbances by vertical solute inflow or effects of dilution, and accelerate denitrofication in horizontal subsurface flow.