시화호 저서생태계의 장기 변동

Abstract

Since the Shihwa dyke construction the lake has undergone unstable environments such as large fluctuation of salinity and oxygen due to irregular exchanges of waters between the outer saline water and the inner brackish one, inflow of a good deal of pollutants from non-point and point sources, and water stagnancy. It indicates that the lake ecosystem has a variability of species composition and species density. Especially, benthic organisms are lacking of ability to cope with changes of environments because most of them are sedentary and are limited in mobility, and thus the variation gives rise to change in the community structure. The Shihwa macrobenthos have responded to the severe environments, and the response was reported in some previous studies. However, these studies referred to succession of macrofauna for only three years of the initial stage after the dyke construction. In the present paper, we report on long-term responses of the macrobenthos to the large variation in salinity and dissolved oxygen for fifteen years after the birth of the lake.d deal of pollutants from non-point and point sources, and water stagnancy. It indicates that the lake ecosystem has a variability of species composition and species density. Especially, benthic organisms are lacking of ability to cope with changes of environments because most of them are sedentary and are limited in mobility, and thus the variation gives rise to change in the community structure. The Shihwa macrobenthos have responded to the severe environments, and the response was reported in some previous studies. However, these studies referred to succession of macrofauna for only three years of the initial stage after the dyke construction. In the present paper, we report on long-term responses of the macrobenthos to the large variation in salinity and dissolved oxygen for fifteen years after the birth of the lake.