Effect of Temperature and Salinity during Spawning Season to the Population of Juvenile of Corbicula japonica in Lake Jusan

Abstract

Population of Corbicula japonica in Lake Jusan increased steeply in 2008. In order to explain the increase, we focused on the environmental conditions of spawning season. The dynamic energy budget (DEB) simulation indicates that C. japoica were able to spawn every year, but they waited for suitable spawning temperature. After spawned, eggs need a certain salinity transforming to larva and juvenile stage. Results of a vertical one-dimensional water quality simulation show that in 2007 the duration of spawning temperature was longer than in the other years, indicating a higher opportunity for all adult C. japonica to spawn. Also, the daily average salinity was close to the ideal salinity transferring eggs to larva and juvenile stage. These two parameters are supposed to be the main factors affecting the high population in 2008