黑龙江水系主要江河浮游植物种群结构特征

Phytoplankton Population Composition 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、图们江的浮游植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植物共计83属215种，种群结构主要是以绿藻、硅藻为主，分别占40．5％和35．3％；硅藻类在各江河中的生态优势度均超过0．5，物种丰富度均超过1．0；各水域之间相似系数均在0．2以上；浮游植物密度与生物量变动为146．48×10^4—668．79×10^4个／L和2．522—7．663mg/L；硅藻生物量与密度都是最高的，分别占62．3％和76．6％；浮游植物生物多样性指数平均为1．281，均匀度指数为0．282；同时探讨了水质污染状况。

The species composition of phytoplankton was investigated in main branches of Heilongjiang river system in May, July, September and November 2003. Results indicate： There were 215 species of phytoplankton belonging to 83 generas were found, in which scenedesmus （40.5%） and diatom （35.5 % ） were predominant. The dominance of Diatom in every branch is more than 0.5 and richness of all Diatom are more than 1.0. Similar eoefficieients in all rivers are above 0.2. The abundance and biomass of phytoplankton vary from 146.48 × 10^4 to 668.79 × 10^4 ind./L and from 2.522 to 7.663 mg/L respectively. The abundance and biomass of Diatom are the highest in all species, occupying 62.3 % and 76.6% respectively. Biodiversity of phytoplankton in Heilongjiang river system was 1.281, with the evenness of 0.282; water quality was also discussed in this paper.