瀬淵構造を持つ河川区間における微地形と水生昆虫の分布に関する現地調査

抄録

Distribution of benthic macroinvertebrates such as aquatic insects seems to be dependent on the physical environment like mean velocity and bed material in lotic environment. We have conducted field survey in which part of a river was dried so that we were able to sample aquatic insects from various places. Survey results showed that aquatic insects which belong to collector-filterer were abundant at places with high flow velocity and those belong to collector-gatherer were found in large number in area where flow velocity is small and sediment settles. Flow pattern controls dominant species because species that has a feeding function which is suitable to the flow environment can be dominant. High correlation between velocity and biomass of collector-filterer was found.