通过小湾大坝蓄水前后8个采样断面的浮游植物、浮游动物和鱼类的对比调查,筛选出适于ESHIPPO模型生态风险评价的广域属种、特有属种(稀有种、特有种、资源种和土著鱼),并对其进行生态风险分析.结果表明:大坝建设对水生物种产生一定程度的生态风险,尤其是对于澜沧江土著鱼类,水文形势改变增加了其生态风险;特有属种如浮游植物红毛藻、中华鱼子菜、溪菜,浮游动物云南棘猛水溞和西南荡镖水蚤等处于高风险状态,必须对其加强监测并采取相应的保护措施;浮游植物和浮游动物的广域属种均处于中度风险状态,对其除监测外应做好保护准备;小湾大坝蓄水后,12种土著鱼(光唇裂腹鱼、澜沧裂腹鱼、云南平鳅、黑线沙鳅、横斑原缨口鳅、拟鳗副鳅、云南四须鲃、宽头华鲮、长臀刀鲇、扎那纹胸鮡、无斑褶鮡、宽纹南鳅)处于高度风险状态,应立即对其采取必要的保护措施,防止其消失或灭绝.
An investigation was conducted on the phytoplankton,zooplankton,and fish at 8 sampling sections in the Manwan Reservoir before and after the construction of Xiaowan Hydropower Dam.The modified ESHIPPO model was applied to study the changes of the featured aquatic species,including endangered species,endemic species,resource species,and native fish,aimed to make an ecological risk assessment of the dam construction on the aquatic species.The dam construction had definite ecological risk on the aquatic species,especially the endemic fish,in Langcang River,due to the changes of hydrological conditions.The endemic species including Bangia atropurpurea,Lemanea sinica,Prasiola sp.,Attheyella yunnanensis,and Neutrodiaptomus mariadvigae were at high ecological risk,and thus,besides monitoring,protection measures were needed to be taken to lower the possibility of the species extinction.The widely distributed species of phytoplankton and zooplankton were at medium ecological risk,and protection measures besides monitoring should be prepared.Twelve kinds of native fish,including Barbodes huangchuchieni,Sinilabeo laticeps,Racoma lantsangensis,Racoma lissolabiatus,Paracobitis anguillioides,Schistura latifasciata,Botia nigrolineata,Vanmanenia striata,Homaloptera yunnanensis,Platytropius longianlis,Glyptothorax zanaensis,and Pseudecheneis immaculate,were at high ecological risk,and protection measures needed to be developed to prevent the possibility of the species loss and extinction.