关键词: 介形类, 太湖, 丰度, 生物量, 环境因子

Abstract:

Fifteen ostracod species were collected from Tai Lake during the period from September 2004 to August 2005.Their abundance and biomass showed a similar seasonal pattern:autumn>summer>spring>winter.Among 15 species,the abundance and biomass of 〖WTBX〗Physocypria kraepelini〖WTBZ〗 and 〖WTBX〗Fabaeformiscandona〖WTBZ〗 cf.〖WTBX〗fabaeformis〖WTBZ〗 were the highest and played important roles in composition of ostracods community in Tai Lake.The mean abundance of ostracods was 1 590 ind/m2,and the mean biomass of ostracods was 46 495 μg(dwt)/m2.There was the same horizontal distribution for the abundance and biomass of ostracods in 9 sampling areas,and then the high abundance and biomass appeared in the east of Tai Lake (such as East Tai Lake,Eastern Coastal Belt and Gong Bay) because of the feeding and behavior habits of ostracods.Among the 9 areas,except for Meiliang Bay and Gong Bay,there was similar seasonal pattern for abundance and biomass in Tai Lake.The differences in Meiliang Bay and Gong Bay were mainly because of high reproduce energy of eurythermal species.Results of Pearson correlations analysis showed:water temperature,transparency,plant density and dissolved oxygen (DO) were important environmental factors affecting abundance and biomass of ostracods in the lake,but there were a few differences with seasons.

Key words: ostracod, Tai Lake, abundance, biomass, environmental factor