| According to clustering way made by Erle C. Ellis, 12 cells were selected from an IKONOS high resolution image of Jintang county and Jianyang City, Sichuan province, as samples representative to study the long-term changes of landscape structure between 1945 to 2002 .And 5 cells were selected to study the soil nutrients spatial distribution. The results are obtained as following:1. Great changes has taken place in village landscapes since 1945 with increasing of population and more strong effects of human activities. The anthropogenic units in landforms, such as house buildings, roads and reservoirs etc, in 2002, increased by 231.23% over 1945, but bench plateau , stream reduced 11.99% and 91.60% respectively. Some steep slopes and summit changed to bench plateau. For landuse, rainfed cropland reduced, but built-up and disturbed area increased by 480.17%. Perennial plant landcover increased by 186.57% over 1945 and sealed landcover by 386.09%. There were 16 kinds of ecotopes reduced, mainly cropland on bench plateau (BPRAac04), mixed open woody land on steep slope (SSTMow02), rice paddy submerged and fallow in winter (FSPAri03) and annual crop land on summit, significantly. The number of increased ecotope types is 27. Perennial evergreen needle leaf tree on steep slope (SSTPen03) increased by 335.52%, multi-story houses with shared wall or courtyard (ANCSho03) by 769.57%. Increased brand-new ecotope types are mainly rice paddy with double cropping season (FSPAri01, BPPAri01), orange orchard (BPRPoe33,SLRAoe33), mixed crop land (BPRMmc01), bamboo on bench plateau (BPTPtg24) and planted evergreen needle leaf tree on steep slope (SSTPen01).2. The heterogeneity of village landscapes in different stratifications has significant difference, and especially Shannon-Weiner indexes, dominance and fragmentation have changed greatly. The Shannon-Weiner indexes and the fragmentations of landform, landuse, landcover and ecotope are 1.4667, 2.2286; 1.3282, 2.4621; 1.1824, 2.8291; and 2.4225, 4.9937 respectively. Comparing the landscape indexes in 2002 with those in 1945, the Shannon-Weiner indexes increased by 15.75-46.61%, the evenness by 13.63-46.61%; the dominance reduced by 3.84-29.53; the relative richness changed from -6.67 to 78.95% and the fragmentation increased by 80.55-153.58%.3. The results of fractal analysis indicate that the fractal dimension of paddy is from 1.1154 to 1.2555, relatively low, reflecting that the structure of paddy is not only affected by landform, but also by human activities greatly. The cropland, forest, hamlet, infrastructure and watercourse have higher fractal indexes (1.3-1.5) and low self-similarity. The landscape fragment indexes are naturally from 0.0240- 0.0424/100m~2, relatively low.3. It is obtained from the modeling analysis of soil nutrients spatial distribution that the spatial variations of soil nutrients are fairly fitted with Spherical, Gaussian or Exponential model, and their spatial autocorrelation degrees are different. Some values and modeling...
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