盐城滨海湿地水鸟类群生境适宜性及生态阈值研究:对栖息地景观结构恢复的启示

A Study on Habitat Suitability and Ecological Threshold of Waterbird Guilds in Yancheng Coastal Wetlands:Implications for Habitat Structure Restoration.

盐城滨海湿地作为以水鸟栖息地保护为主的新晋世界自然遗产地,其水鸟栖息地保护现状和面临的潜在问题备受各界关注。选取盐城滨海湿地5个主要水鸟栖息地,基于野外调查获得的鸻鹬类、雁鸭类和鹭类的环境和生境等数据,综合运用地理信息技术、随机森林算法(RF)和阈值分析方法(TITAN),开展3类水鸟适宜生境识别和环境变量阈值分析。结果表明:鸻鹬类主要分布在条子泥栖息地和核心栖息地东缘;雁鸭类主要分布在条子泥和核心栖息地的农田和芦苇沼泽地;鹭类主要分布在各块栖息地的养殖塘和芦苇沼泽地;雁鸭类在5块栖息地内适宜区域面积占比均小于鸻鹬类和鹭类。影响3类水鸟在适宜区域分布的主要环境变量有生境类型、到水面距离、植被覆盖度、到芦苇距离、到主要道路/海堤距离和到农田距离,涵盖了生境类型、植被盖度和距离等环境指标。各水鸟类群内部对主要环境变量的正负响应阈值存在物种数量上的差异,同时类群间对环境变量的响应阈值也不同。最后提出了维护盐城滨海湿地水鸟种群多样性和恢复栖息地景观结构的建议和方案。

Yancheng coastal wetland is a new world natural heritage site,which mainly focuses on waterbird habitat conservation.The current status and potential problems of waterbird habitat conservation have attracted much attention from scholars.In this study,five major waterbirds habitat sites in Yancheng coastal wetland were selected.Based on the data of three waterbirds guilds,environmental variables and habitat types obtained from field survey,GIS technology,random forest(RF)and threshold indicator taxa analysis(TITAN)were used to identify the suitable habitat of the three guilds and analyze the response threshold of environmental variables.The results show that the shorebirds were mainly distributed in eastern edge of Tiaozini habitat site and Core habitat site,anatidae was mainly distributed in farmland and reed marshes of Tiaozini and Core area,and herons were mainly distributed in aquaculture ponds and reed marshes of each habitat site.The area proportion of suitable areas of antidae in the five habitat sites was smaller than that of shorebirds and herons.T_hab,D_wat,P_fvc,D_ree,D_swa and D_far were the main environmental variables affecting the distribution of the three guilds in suitable areas,covering environmental indicators,such as habitat type,vegetation coverage and distance indicators.There were differences in the number of species in the positive and negative response thresholds of the main environmental variables in three guilds,and the response thresholds of the waterbird guilds to the environmental variables were also different.Finally,some suggestions and schemes for waterbirds diversity maintenance and habitat landscape structure restoration in Yancheng coastal wetland were proposed.