棉花滩水库浮游生物群落结构特征研究

为探究紫金铜矿事故后棉花滩水库浮游生物群落结构的基本情况,保护水域生态环境,提高水面综合利用效益,恢复生产秩序及水域合理生态结构,根据水库型态设置22采样点,对棉花滩水库浮游生物的密度及生物量进行了监测.结果表明,浮游植物6门、35属、43种,密度为14.16×104～ 131.66×104个/L,平均密度为42.89×104个/L,生物量为0.096 ～7.174 mg/L,平均生物量为1.401 mg/L,浮游植物生物量和密度在空间上呈现从上游至下游逐渐降低的趋势；Shannon-Wiener多样性指数在0.628 ～2.671,Pielou均匀度指数为0.231 ～0.839,根据评价标准判断,大都属轻度污染.浮游动物4门、13种,密度为36 ～ 285个/L,平均密度为个79个/L,生物量为0.154 ～3.110 mg/L,平均生物量为1.421 mg/L；多样性指数为1.300 ～2.441,均匀度指数为0.625～0.982.棉花滩水库浮游植物为硅藻-绿藻型,生物评价其属于中营养型；事故发生水域浮游生物群落结构受到外界的干扰,呈现不稳定状态.

Research on characteristics of community structure of plankton in Mianhuatan Reservoir

Objective: To explore plankton community structure in Mianhuatan Reservoir after Zijin copper accident and to provide a reference for protecting ecological environment, improving the utilization efficiency of the water, and recovering the production order and the reasonable ecological structure in the waters. Methods: Set the sampling points according to the water body environment and the situation of pollution. Water samples were detected by the density and biomass of plankton. Qualitative samples were inspected by microscopy. Results: We found 6 phylum, 35 genus and 43 species of phytoplankton with a density being 14.16×104-131.66 ×104 ind./L, the mean density 42.89×104 ind./L, biomass 0.096-7.174 mg/L, and the mean biomass 1.401 mg/L, the biomass and density of phytoplankton presented trend of gradual decline from top to bottom. The diversity index fluctuated in the 0.667-2.671, and the evenness index was in the range of 0.231-0.839. The Mianhuatan Reservoir mostly belong to mild contamination, according to the evaluation standard. There were 4 phylum, 13 kinds of zooplankton in the waters with a density being 36-285 ind./L, the mean density 79 ind./L, biomass 0.154-3.110mg/L, and the mean biomass 1.421 mg/L, The diversity index and evenness index were 1.300-2.441 and 0.625-0.982. Conclusion: The diversity indices of phytoplankton and some other datas showed that the waters were geared to middle nutrition reservoir and that the plankton community structure of a part places was unstable and susceptible to outside interference.