黄渤海濒危水鸟栖息地动态变化研究

中国滨海湿地是东亚-澳大利西亚迁徙路线上候鸟重要的停歇地、繁殖地和越冬地，土地利用变化所引发的滨海湿地退化导致水鸟栖息地类别和面积发生了很大转变，影响迁徙水鸟种群数量的稳定性。然而，土地利用变化在哪些区域和多大程度上影响了迁徙水鸟的栖息地分布尚不清晰。以土地围垦典型区域黄渤海滨海湿地为研究区，以受胁濒危水鸟物种勺嘴鹬、大滨鹬、大杓鹬、小青脚鹬、黑脸琵鹭、黄嘴白鹭、遗鸥、黑嘴鸥为研究对象，结合物种分布模型MaxEnt和GIS空间分析，模拟2000、2015、2020年水鸟栖息地时空分布，探索过去20年栖息地分布的时空变化，分析水鸟种群变化趋势，识别水鸟栖息地保护优先区域，提出水鸟栖息地保护管理建议。结果显示：2000—2020年，8个水鸟物种栖息地主要分布在渤海湾、莱州湾、江苏盐城沿岸、如东-东台沿岸区域。所有物种的栖息地面积均呈不同程度的下降趋势，其中7个物种栖息地下降比例超过50%,下降的区域主要分布在渤海湾、江苏盐城沿岸、东台条子泥、小洋口沿岸，滨海湿地丧失是导致水鸟栖息地面积下降的直接因素。7个物种种群数量呈下降趋势。研究所确定的水鸟保护优先区面积达240.32 km^2...

Variation of waterbird habitat in the Yellow and Bohai Seas, China

Coastal wetlands in mainland China are home to rich fishery resources, mangroves, and seagrass beds. They are recognized as key part of global biodiversity, providing the natural eco-safety barrier for the development of economically developed coastal regions in China. They not only offer preciously natural resources, but also are key components of a biotic community of mountains, rivers, forests, croplands, lakes and grasslands for their important ecological functions and values. Coastal wetlands in China provide important stopover sites, breeding areas and non-breeding areas for migratory waterbirds along the East Asian-Australasian Flyway (EAAF). Nevertheless, the problems of wetland loss and function degradation still exist and are widespread due to a wide range of factors, such as fast industrialization and urbanization, the increased pressure of wetlands and their biodiversity loss, lack of coordinated wetland management systems, over-lapping of different administrative functions, and conflict among different sectors'' policies on wetland management. Loss in coastal wetlands due to land use change resulted in dramatic change in habitat category and area, and further reduced the stability of waterbird population. However, it is still unclear where and how land use change has had impact on the distribution of waterbird habitats. In this study, we regarded coastal wetlands along the Yellow and Bohai Seas that a hotspot of land use change occurred as study area. We selected eight endangered species, i.e., Spoon-billed Sandpiper, Great Knot, Far Eastern Curlew, Nordmann''s Greenshank, Black-faced Spoonbill, Chinese Egret, Relict Gull, and Saunders''s Gull as targeted species. We combined species distribution model MaxEnt and GIS to estimate habitat distribution and their spatio-temporal changes between 2000 and 2020, and to assess the trend of waterbird population changes. Then we identified priority areas for conservation, and provided recommendation on conservation and management. The results showed that the waterbird habitats were mainly distributed in Bohai Bay, Laizhou Bay, and the coastal areas along the Yancheng and Rudong-Dongtai between 2000 and 2020. During that period, the habitat area of all eight species declined, among which the habitat area of seven species has lost more than 50%, and these areas occurred in Bohai bay and the coasts along the Yancheng, Tiaozini, Dongtai County, Xiaoyangkou, and Rudong County. Coastal wetland loss was a direct factor behind the decrease of waterbird habitats. The populations of seven species tended to decline. We identified priority areas for conservation with a total area of 240.32 km², and the coast of Rudong County was defined as a conservation gap area. We recommended expanding the boundary range of Yancheng world heritage site to include the unprotected area. It is necessary to improve conservation and management and reduce continuous loss of waterbird habitats. It is also important to engage the general public in the protection of waterbird habitats and promote the protection of new natural protected areas.