| 其他摘要 | Through field works in the Wudongde Hydroelectric Station influented area of the Jinshajiang River, and some other survey materials, we list 157 phytoplanktons, 153 zooplanktons, 60 zoobenthoses, 15 aquatic plants, and 107 fishes. The number of fish species is high, and there are a lot of endemic species which only distribute in upper Yangzi River basin. Fish fauna presents the character of the East Asia Biology Group and obviously complex transitivity. The formation of this fauna depends on Jinshajiang River`s geographical history in which headword capture and flow direction change occurred because of tectonic uplift of Qinghai-Tibetan and Yunnan-Guizhou Plateaus. Based on the environment changes in the estimated area, such as water level, current, water temperature and sediment etc, and united with biological characters of wildlife which distributed in this area, we evaluate the influences which may be caused by the hydroelectric station. The influences should be continual, the river ecology will be broken, heterogenicity of the river environment will reduce, river natural rhythm will change, productivity of the river bank will degrade, nutritive material will enhance. These changes should cause the loss of biodiversity, reduction of endemism, reducement of fauna heterogenicity and destruction of the river bank community. The river ecological system will change to reservoir style. The analysis on the influence to the fishes indicates that the dam will interrupt the migration channels, flood spawning sites, destroy habitats of endemic species, which might change the original fish fauna obviously. All of the hydroelectric station steps in lower Jinshajiang River will bring cumulative environmental impacts. The biological fauna of this area will change completely, biodiversity will reduce and endemic species will degrade. Considering biodiversity as the conservation emphasis, combining practical work operability, we confirm the key fish species and conservation priority of the estimated area. We present ecological compensation suggestions such as aboriginal species preservation, fry releasing, enhancement of river management etc. At the same time, to release the cumulative ecological impacts caused by the hydroelectric station steps in lower Jinshajiang River, we suggest constructing endangered and endemic fishes national natural reserve of the middle and upper Jinshajiang River which aims to conserve aquatic wildlife resources and reduce the influences on the ecological system caused by the construction of the hydroelectric station. |
修改评论