razing rates of zooplankton in different size groups on bacterioplankton were studied in spring of 1990,in lake Donghu,Wuhan.The results show that bacterioplankton is an impor- tant food resource for zooplankton,especially for protozoa and rotifera,which contribute al-most 75%of the commtinity.It plays an important role in energy flow of this lake ecosys-tem,The total clearance rate of the zooplankton community on bacterioplankton was 180.10ml/1.h,total feeding rate was 0.40μgCl￣(-1)h￣(-1).Grazing rate of z...