Abstract
Fragmentation of lotic habitat by a drought is assumed to intercept the longitudinal movement of organisms and alter the community structure of them. In this study, we compared the community structure of freshwater animals between upstream and downstream of intermittent reach caused by human activities, in order to reveal the impacts of drought on spatial distribution of stream fish and invertebrates. Obvious influence of droughts was not observed for the community structure of fish and invertebrates. In contrast, spatial distribution of some dominant invertebrate taxa was seemed to be altered by droughts. However, there remains a possibility that strong effects of physicochemical habitat condition on invertebrates were more important than influence of a drought.Fragmentation of lotic habitat by a drought is assumed to intercept the longitudinal movement of organisms and alter the community structure of them. In this study, we compared the community structure of freshwater animals between upstream and downstream of intermittent reach caused by human activities, in order to reveal the impacts of drought on spatial distribution of stream fish and invertebrates. Obvious influence of droughts was not observed for the community structure of fish and invertebrates. In contrast, spatial distribution of some dominant invertebrate taxa was seemed to be altered by droughts. However, there remains a possibility that strong effects of physicochemical habitat condition on invertebrates were more important than influence of a drought.
