| Firstly, the method of landscape pattern analysis and meta-community research status were summarized, which is the theoretical basis for this study. Then the appropriate vegetation index was selected, and the exponential model was established. Based on TM remote sensing data in 1992, the landscape pattern of typical island-habitat in Thousand Island Lake Area of Hangzhou Chun'an County was analyzed using remote sensing and GIS methods. The normalized difference vegetation index of this region was estimated, and the area-effect and distance-effect of islands were analyzed and discussed.The research of landscape pattern of Thousand Island Lake area showed that patch density of this area is relatively low (6.91), showing the habitat fragmentation phenomenon. However, the landscape aggregation and connectivity were at a high level (94.90 and 99.46 respectively), and the edge of landscape was open. This would be helpful for material, energy and information exchange between patches and also would promote the increase of species diversity. Analysis of the landscape pattern of the islands with different areas showed that the bigger the island is, the weaker the fragmentation is, and the higher the aggregation and connectivity between the islands is, the more significant the edge effects is.When studied the area effect of islands, the values of NDVI of islands with different areas, and the landscape pattern of island patches with different grades of NDVI were studied. The results showed that the NDVI of super-large, large, middle and small islands, were 0.24,0.17,0.15 and 0.07 respectively, showing a decreasing trend, which revealed significant positive correlation between the size of island and their NDVI values, i.e., the larger the island area is, the better the plant growth status on it is. The landscape pattern of patches with various NDVI grades within the different types of islands influenced on its overall level of NDVI values to some extent. The entire landscape suffered from high degree of fragmentation. The results showed that the larger the island area is, the smaller the density of patches with various NDVI grades is, the weaker the degree of fragmentation is, the stronger the cohesion of patches with same NDVI grade is, the more diverse the landscape types is, and the evener the distribution of patches of each type in the landscape is. Such vegetation pattern is conducive to the migration and colonization of individuals or propagules of species, as well as the functional linkage between local plant communities in the islands with different NDVI grades, and the maintenance of stability of community structures, which tended to result in the relatively high overall level of NDVI. The results of landscape index of NDVI patch grades in Thousand Island Lake area reflect the status of the plant communities on them well.The distance effect of islands was studied, and the minimum distance to mainland 1 of samples 1,2 and 3 showed an increasing trend, and their NDVI values showed a decreasing trend, which were 0.16,0.09 and 0.07 respectively. This indicated that the closer the island to mainland is, the higher the aggregation level of islands is, and the higher NDVI value is. According to the vegetation quality of mainland 1 and 2, the closer the island to the mainland with good vegetation is, the better the vegetation status on the islands is.The correlation analysis of NDVI values with area and distance of islands showed significant positive correlation between NDVI values and areas of islands, and insignificant negative correlation between NDVI values and distances of islands.The results of the study of area effect and distance effect of islands reflected its vegetation status. This result deepened the understanding of the landscape patterns of the area, which preliminarily tested the adaptability and feasibility of the methods of remote sensing and GIS in studying the vegetation status on island-habitat in general.
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