With the aid of the 3S technology,a baseline landscape of the Yalujiang Estuary was established as reference for analysis and assessment of landscape fragmentation of the coastal wetland therein in 1989 and 2005,using indicators,such as natural landscape index,patch density,largest patch index,patch shape index and contagion index.Results show that the baseline landscape is a useful reference for assessment of landscape fragmentation.The wetland landscape of the Yalujiang Estuary tended to break into patches with natural index declining to 89.373% in 1989 and to 86.691% in 2005.Among the different types of wetlands,reed swamps,mudflats and tidal furrows shrank significantly in acreage with natural index falling down to 69.94%,71.49% and 78.42%,respectively in 2005.The index of patch density of wetlands of all the types increased,with that of reed swamps ranked first,being 18.507,and that of mudflats second,being 6.879 in 2005.Mudflats tended to become more complex in shape of patches while the other types displayed a reverse trend.The contagion index remained high for all the types of wetlands in all the periods,suggesting that the various types of wetlands are distributed in cluster in the Yalujiang Estuary.%在3S技术支持下构建了鸭绿江口滨海湿地景观本底格局,并以本底格局为参照,分别对1989年和2005年鸭绿江口滨海湿地景观破碎化过程进行了监测评价.结果表明:湿地本底格局可作为强度开发环境下湿地景观格局破碎化评价的参照依据.与本底格局相比,鸭绿江口湿地景观格局呈持续破碎化趋势,1989年和2005年湿地景观整体自然度分别为89.373%和86.691%.在不同自然湿地景观类型中,芦苇沼泽、滩涂和潮沟面积萎缩幅度较大,2005年其自然度分别为69.94%、71.49%和78.42%;各湿地类型的斑块密度都出现了不同程度的增大,其中芦苇沼泽和滩涂增大最明显,2005年斑块相对密度分别达18.507和6.879;滩涂斑块形状趋于复杂,2005年斑块相对形状指数为1.085,其他湿地类型斑块形状则持续简化;各时期不同自然湿地类型斑块聚集度指数均较高,反映出鸭绿江口各湿地类型多呈聚集分布的空间格局.
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