| Based on aerial photographs of 1996(1:35000), forest type map of 2001 (1:25000) and terrain map (1:25000), the forest landscape pattern of Xiaokeng small basin, the part of Laoshan Natural Conservation area in Anhui Province, was analyzed. The study area covers 3779. 64 hm2. In the paper digitized map was built and above aerial photographs were analyzed using 3S techniques to identify forest vegetation types, then these information was modified with the existent inventory data and field survey to establish a GIS and database eventually. According to all above information, a three-order classification system for forest landscape was built, and landscape maps for each order were drawn; The landscape indices such as the size of patch, the density of patch, dominance, diversity, shape index,patch shape index for similar to circle,fractal dimension of patches, nearest neighbor index and connectivity were calculated using ArcGIS3.0 software and methods of landscape ecology; In additions the geographical data including slope, aspects, and elevation were got from DEM using the spatial analysis function of GIS, which were employed to make statistic analysis of the relationships between forest landscape types and geographical factors, and to describe the current landscape pattern after closed for years. The results showed: 1. After closing for afforestation for years, because of appropriate management and protection had done, the reverse succession of forest vegetation had stopped, and vegetation recovered from regeneration in a relatively short period in Xiaokeng. It was calculated that the forest coverage has already reached to 95.95%, some forest types were similar more or less to zonal vegetation in the characteristics of both species composition and structure, and forest vegetation become the main element of landscape composition which was also a controlling element of local environment. In fact, the Xiaokeng river basin becomes a typical forest landscape. 2. According to three-order classification system, there were 9 landscape elements in the first class in Xiaokeng forest landscape, and broad-leaved forest was predominated. Especially, under the item the secondary mixed forest composed of evergreen and deciduous broad-leaved trees accounted for 68.68%, which were mostly regenerated naturally. In addition, the middle-age stand distinguished by the time of closed for afforestion was in the majority. 3.The forest landscape was mainly distributed at the vertical zone of 300m-900m altitude, slope of 15°～45°, aspect of west, southeast, north, northeast, east and northwest. This was correlated closely with topography, vegetation type, species composition and the history of artificial disturbance. 4 The proportion that different landscape types accounted for showed a significant difference, it indicated that Xiaokeng forest landscape had higher heterogeneity. But it had higher shape similarity between evergreen and deciduous broad-leaved mixed forest and Xiaokeng forest landscape, it occupied the absolute predominance and played an important role in landscape function. 5.The forest landscape diversity of Xiaokeng was 2.336, and its evenness 0.613. It showed that there were abundant forest types with more landscape information; but the lower evenness indicated that they had irregular distribution pattern slightly. The landscape diversity of secondary forest regenerated naturally was 2.272, and its evenness 0.757, so it had higher heterogeneity, and high evenness too. The dominance, reduced with the research scale reduced, and it was 1.540, 1.481and 1.098 in three classification order. 6.The patch densities of landscape elements were obviously different, that of broad-leaved forest was lower, other types were higher. 7.The patch shape of Xiaokeng forest landscape was relatively simple; in general the shape of natural secondary stands were more complicated than that of plantations. The patch size of broad-leaved forest was much larger, and the patch number of tea garden was at most. 8.Grains structure...
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