The plankton and trophic state of Lushui Reservoir

根据1991年1~12月的调查,陆水水库的浮游植物共8门118属,以绿藻、硅藻、蓝藻门的种类为主,占总属数的86.44%;浮游动物198种,其中原生动物38种、轮虫68种、枝角类61种、桡足类31种。浮游植物年平均数量和生物量分别为3.1449×106cell/L和1.937mg/L,数量以蓝藻、隐藻、硅藻最多,占总数量的91.33%,生物量以隐藻、硅藻、绿藻最大,占总生物量的85.03%,浮游植物初级毛产量为3.4gO2/m2·d。浮游动物年平均数量和生物量分别为2323.8ind/L和1.4837mg/L,数量以原生动物和轮虫最多,占96.89%,生物量以枝角类和桡足类为主,占79.94%.陆水水库浮游生物种类组成和现存量在不同的水域差异较大,季节变化明显。按水化学分析结果及浮游生物特征判定,陆水水库的营养类型为中营养型。还讨论了环境因子对水库浮游生物的影响。;The plankton and hydrochemistry are surveyed in Lushui Reservoir, Hubei Province from January to December.1991.The results show that there are 118 genera of phytoplanktion and 198 species of zooplankton.The average density of phytoplankton and zooplankton is 3.1449×106 cell/L and 2323.8 ind./L respectively and the average biomass 1.937 mg/L and 1.4837 mg/L respectively, in which Cryptophyta.Bacillariophyta, Cladocera predominated.The species composition and standing crop of plankton vary with different regions and seasons.The mean gross primary productivity of phytoplankton reaches 3.4g02/(m2·d).but phosphate is still a limited element to it.According to the characteristics of plankton and the data of hydrochemistry.Lushui Reservoir belongs to mesotrophic type. The effects of environmental factors on the plankton of Lushui Reservoir are also discussed in this paper.