군위댐 건설 공사가 저서성대형무척추동물 군집 변동에 미치는 영향

Abstract

Benthic macroinvertebrates were seasonally sampled from upstream and downstream of the Gunwi Dam construction site from 2006 to 2012. Totally 148 and 165 species were collected at the upstream and downstream sampling sites, respectively. At the upstream area after dam construction, there was no significant change of the numbers of non-insect taxa, but at the downstream area, the non-insect taxon numbers were increased gradually. The individual ratio of Ephemeroptera and Diptera had higher value than the other taxa in both of up and downstream. The trichopteran individual ratios were increased in upstream sites, but decreased in downstream sites from 2010. Also, non-insects and coleopteran individual ratios were decreased in upstream, but increased in downstream after completion of dam construction. The annual range of fluctuation in community indices narrowed after construction. According to a functional feeding group analysis, the individual ratios of FC (Filtering Collector) were increased, and GC (Gathering Collector) and SC (Scraper) were decreased in upstream sites annually. In contrast, the annual individual ratios of FC were decreased, and GC and SC were increased in the downstream sites.