崇明东滩鸟类栖息地优化区越冬水鸟的栖息地利用及影响因子

Habitat Use and Factors Affecting Distribution of Wintering Waterbirds in the Wetland Restoration Area at Chongming Dongtan

阐明水鸟栖息地利用与环境因子的关系有助于制定针对性的水鸟保护对策。本研究在2012～2013年冬季对崇明东滩鸟类栖息地优化区内越冬水鸟的种类、数量以及6种环境因子（植被面积比例、裸地面积比例、水深、地形变异、栖息地结构多样性和干扰）进行调查，以了解水鸟对人工湿地的栖息地利用及其影响因子。野外调查共记录到水鸟24种9018只，其中优势种为斑嘴鸭（Anas poecilorhyncha）和绿头鸭（A．platyrhynchos）；栖息地优化区内水鸟休息的个体数量占总数量的79．2％，这表明优化区是大多数水鸟的休息地，而小鹏鹧（Tachybaptus ruficoUis）、白骨顶（Fulicaatra）、黑水鸡（Gallinula chloropus）、白琵鹭（Platalea leucorodia）和黑脸琵鹭（P．minor）的觅食个体数量超过60％，说明优化区也为这些鸟类提供了觅食地。逐步回归分析表明，裸地面积比例是影响越冬水鸟种类分布的最主要因子；尽管游禽在地形变异较大、植被面积比例较低的区域数量较多，但在休息时游禽更偏好于裸地面积比例较高的区域，而涉禽休息时偏好于地形变异较大的区域。为增加栖息地优化区内的水鸟多样性，建议在优化区内种植水鸟可食的沉水植物以增加水鸟的食物资源，同时增加裸地面积比例和地形变异程度，更好地为水鸟提供栖息地。

Clarifying the relationship between habitat use of waterbirds and environmental factors contributes to making conservation strategies. In order to understand the use of waterbirds on artificial wetlands and factors affecting their habitat use, we surveyed waterbird species and numbers and six environmental factors （including vegetation area, ratio of bare land area, water depth, topographic variation, habitat structural diversity, and human disturbance） in the wetland restoration area at Chongming Dongtan in the winter of 2012 -2013. A total of 9 018 individuals in 24 species were recorded during 12 surveys. Spot-billed Duck （Anas poecilorhyncha） and Mallard （A. platyrhynchos） were the dominant species, accounting for 47.5 and 32.7% of total individual numbers, respectively. Rest behavior was recorded in 79. 2% of total individuals, suggesting the wetland restoration area provided roosting sites for most waterbirds. Moreover, over 60% of individuals showed foraging behavior in Little Grebe （Tachybaptus ruficollis ）, Coot （Fulica atra ）, Common Moorhen （Gallinula chloropus） , Eurasian Spoonbill （ Platalea leucorodia ） , and Black-faced Spoonbill （ P. minor）. Stepwise regression analysis indicated the proportion of bare land area is the main factor affecting the species numbers of waterbirds ; although waterfowl preferred plots with large topographic variation and low cover of vegetation, they stayed in plots with high proportion of bare land area. For the waders, they preferred to rest in plots with large topographic variation. To increase waterbird diversity in the wetland restoration area, we suggested to improve the food conditions for waterbirds, such as planting more submerged plants, and to increase the topographic variation and the proportion of bare land area.