Study on the Benthic Macroinvertebrates in the Middle Reaches of the Paenae Stream , a Tributary of the Naktong River , Korea

배내천 中流의 底棲性 大形無脊椎動物에 대한 硏究 1. 群集分析 및 生物學的 水質 判定

Benthic macroinvertebrates were collecte in the middle reaches of the paenae stream, a tributary of th naktong river in korea, in four seasons from August 1989. To may 1990, during the study period, 125 species, 81 genera and 41 families were collected. Overall, the most dominant species was lepidostoma sp. 1 followed by heptagenia kihada, neoperla quadrata, diamesa sp. 1, ect.. the community was most diverse in autumn, However the number of collectd individuals was highest in winter. Species of chironomids including diamesa sp. 1 and mayflies including paraleptophlebia chocorata were collected exceptionally in a large number in winter. Seasonal occurrence of funtional groups such as collectors, shredders and scrapers was related with the availadlity of food sourses in the stream. The abundance of predators was relatively stable in four seasons with 17% on average. Diversity, tbi and chandler's biotic score(bs) in the paenae strem were 3.75, 14.5, and 100 on average, respectively. Based on biological and chemical indices the paenae stream was clean in the range of xeno- and oligo- saprobity.