基于水文地貌分类的滨海湿地生态功能评价——以盐城滨海湿地为例

盐城滨海湿地生态功能的空间差异对该区的保护/开发具有重要的指导意义,水文地貌分类为生态功能的评价提供了良好的前提条件。根据盐城滨海湿地2006-2007年Alos遥感影像数据制作湿地景观图,同时通过DEM和水文水动力条件图,借助Arcgis9.2的空间分析功能确定水文地貌单元(HGMU)。在此基础上,利用实地调查数据和湿地景观数据对不同水文地貌单元的湿地生态功能进行评价。结果表明:(1)盐城海滨湿地包括7类水文地貌单元(HGMU),不同HGMU生态系统类型差异较大;(2)同种HGMU生态功能基本处于同一等级,不同HGMU的生态功能差异明显;(3)盐城海滨湿地不同HGMU单元生态功能由大到小排序为:淡水双向-冲积区(河口)、海水天双向-泥粉砂带、海水月双向-泥滩带、海水年双向-草滩带、淡水单向-冲积区、淡水单向-海积区和淡水单向-冲积海积区。其中,河口湿地、淤泥质滩涂和草滩带湿地在维护盐城海滨湿地生态功能中具有重要地位。

Assessment of ecological functions for coastal wetlands based on hydrogeomorphic units: a case study on coastal wetland of Yancheng, Jiangsu Province, China

Understanding the spatial differences of ecological functions of the coastal wetlands in the Yancheng is of great importance for wetlands protection and exploitation.Hydmgeomorphic unit(HGMU)is a base condition for ecological function assessment.Based on the distribution of wetland types abstracted from Alos imagery in 2006-2007 and field surveying on hydrological condition and DEM(1:25000),the hydrogeomorphic units were determinated for evaluation of wetland ecological functions in the study area.The results showed that the coastal wetlands of yancheng Call be classified 7 HGMUs.Each HGMU has similar ecological functions,and different HGMU has clear different ecological functions.Among these HGMUs,the double direction of freshwater-flooding area(estuary area),daily tide-mud and sand fiat area and monthly tide-murat,as well as annual tide-grass flat area had better ecological functions than other areas in the coastal wetlands of Yancheng.Therefore,to conservation these HGMU wetlands are of significant importance for maintaining regional ecological functions in the coastal area.