长洲水利枢纽建坝后对库区水鸟影响的预测分析

Prediction of impacts of Changzhou Water Conservancy Project on waterbird in the reservoir area

长洲水利枢纽库区分布有４１种水鸟，其中３８种是涉禽，它们主要栖息于河谷带。环境影响评价分析表明，大坝建成蓄水后将给涉禽带来很不利的影响。由于生境的改变，库区水鸟群落将发生变化，涉禽的种类和数量将减少，而游禽的种类和数量将增多。建议开展受威胁的珍稀水鸟海南（Ｇｏｒｓａｃｈｉｕｓｍａｇｎｉｆｉｃｕｓ）的生态生物学研究，以便提出有效的保护措施。

There are 41 waterbird species in the Changzhou reservoir area. Of them, 38 species are grallatores. These waterbirds occur mainly in the river valley. An environmental assessment based on the habitats and ecological characteristics of waterbirds predicted that construction of the dam will make negative impacts on the grallatores.  The habitats are divided into five types: (1) water surface of the river; (2) sandbank and small islands; (3) farm field along the river valley; (4) ponds along the bank;(5) small streams. The second type, sandbank and small island, will be lost almost completely, and hence the grallatores in this habitat will be seriously disturbed. The 30 wading bird species in this habitat will decrease to 12 species, and 96.5 percent of the bird populations will decrease.The prediction analysis indicate, in the whole reservoir area, that five wading bird species will disappear when the dam is built. Of them,Chinese Egret (Egretta eulophotes) and Sacred Ibis (Threskiornis aethiopicus) are stateprotected bird species. The populations of 16 wading bird species will decrease to less than 20 percent,and four species will decrease to 20～50 percent, five species to over 50 percent. Five wading bird species will be slightly influenced. Only one wading bird species will increase their populations. Due to the change of the habitat, a succession of waterbird community will take place with the number of species and populations of the grallatores decreasing and the natatores increasing.The critical endangered species Whiteeared Night Heron (Gorsachius magnificus) is also impacted. It is suggested that a further survey on ecology of the species should be carried out so that an effective conservation measurement may be found.