黑龙江水系主要江河浮游动物种群结构特征

Population Structure of Zooplankton in Heilongjiang River System

2003年5-11月，对黑龙江水系具有代表性的黑龙江、乌苏里江、绥芬河、图们江的浮游动物种群结构特征进行了研究，结果表明：黑龙江水系主要江河浮游动物共计100属种，种群结构主要是以原生动物、轮虫为主，分别占31％和47％；各江段的生态优势度均在0．9左右，物种丰富度均超过0．7；各水域之间相似系数为0．1321～0．3222；浮游动物密度与生物量分别为2035.5～6859．1个／L、0．2480～0．9075mg／L，生物量与密度均以黑龙江最高（0．9075mg／L和6859．1个／L）；浮游动物生物多样性平均为0．830，均匀度指数为0．539。同时探讨了各水域生物多样性。

The species composition of zooplankton was investigated in the main branches of Heilongjiang River system including Heilong, Wusuli, Suifen and Tumen rivers in May, July, September and November 2003. Results showed that there are 100 species of zooplankton, in which protozoa （31.0%） and rotifer （47.0%） are predominant. The superiority of zooplankton is over 0.9, and the abundance ratio is over 0.7. The similarity coefficient ranges from 0.132 1 to 0.322 2, and the density of zooplankton and the community biomass are from 2035.5 to 6 859.1 individuals/L and 0.2480 to 0.9075 mg/L, respectively. The density and biomass are the highest in Heilong River （6 859.1 individuals/L and 0.907 5 mg/L）. The mean biodiversity is 0.830, and homogeneity index is 0.539. Moreover, the biodiversity in all the rivers was also studied.