Influence of Landscape Pattern Index on the Area Extracted from ETM~+ and MODIS

The water body maps of different landscape pattern with 30m and 250m spatial resolution were derived from 8 MODIS scenes and Landsat ETM+ scenes at the same time in order to study the impact of resolution on the water body extraction with different spatial patterns.It is found that the error is small as edge density of the region is low while the error is large as edge density of the region is high.The study area was divided into three regions with different fragmental level according to edge density of the water body.Considering ETM+ water maps as reference,the MODIS water maps overestimate the areas of less fragmental and more fragmental,and underestimate the areas of the most fragmental.As for less fragmental water body,MODIS data can get nearly the same accuracy comparing with the ETM+ data.Landscape metrics can improve MODIS area estimates only for more fragmental water,as showed by higher values of the coefficient of determination for multiple than for simple regression.But for the most fragmental water body,the accuracy can hardly be improved by introducing landscape pattern indices.