The Wintering Habitats of Migrant Birds and Their Relationship with Water Level in Poyang Lake,China
XIA Shaoxia1,3,YU Xiubo1,FAN Na2(1.Key Lab of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences andNature Resources Research, Chinese Academy of Sciences, Beijing 100101,China;2.Jiangxi Normal University, Nanchang 330022,China;3.Graduate University of Chinese Academy of Sciences, Beijing 100049,China)
Poyang Lake is the largest lake in China, offering an important stopover site formigratory bird along the East Asian-Australasian Flyway. Lower water levels and longer dryseason persisting in Poyang Lake in recent years would affect such a process. In this context aproject for Poyang lake water-control project is being launched by the local government. Impact ofincreased water level on aquatic organisms, especially on waterfowl, has become a significantissue. The purpose of this study is to investigate the effect of water level changes on migratorybirds. Considering elements of ecological feature, food selection, and habitat preference of migrantbirds during the wintering period, approaches and standards to distinguish bird habitats arepresented. In the meanwhile, 25 scenes of satellite imageries from 2000 to 2008 and long timeseries water level data from 1962 to 2008 were jointly used to classify waterfowl habitats. Therelationship among areas of habitat and water level are analyzed in detail. Effects of the planningPoyang Lake key water-control project on migrant birds and their habitats were comprehensivelyevaluated, with providing measures to conserve wetland and migrant birds. Results indicated that:1) in terms of feeding characteristics, waterfowl can be conceptually divided to six functionalgroups, and the diverse functional groups had a variety of feeding targets. Birds select feeding sitesin accordance with food abundance and accessibility. Most of waterfowls are distributed alongzones with sedge marsh, mudflats, or shallow water less than 60 cm deep; and 2) habitat areassuitable for migrant birds account for roughly one forth to two thirds of the Poyang Lake wetland atdifferent stages in winter. Habitat areas are strongly affected by a changing water level,particularly, more sensitive when the water level is high. Lower water levels in winter and springhad an immaterial effect on birds and their habitats. The habitat area is generally large when thewater level reaches 11 m and 12 m (Wusong elevation). The habitat areas sharply shrink withwater level rising; In this situation, it is diffcult to find the suitable habitat for birds when waterlevel is higher 14 m (Wusong elevation).
【Fund】： 国家重点基础研究发展计划(973计划):“中国主要陆地生态系统服务功能与生态安全”(编号:2009CB421106);; 国家科技支撑计划:“国家生态恢复重建的综合监测评估关键技术研发”(编号:2006BAC08B05)
【CateGory Index】： Q958
【CateGory Index】： Q958