| Subalpine region plays principal role in Natural Forest Protection Project in Western Sichuan. Based on TM image in 1985, SPOT5 image in 2005, forest distribution map, forest resource secondary surveying, topographic map, land use plan map, survey data and others, with the support of Remote sensing (RS) and Geographical Information System (GIS), Combined with the Digital Terrain Model (DEM), the theory and method of landscape ecology were used in this paper. The landscape pattern and dynamic processes were completely analysed in serial time and spatial space. The landscape ecology construction, landscape present situation, dynamic processes and ecology estimation were studied in detail. Based on the change of land use to make landscape ecology plan, the landscape ecology restoration region was raised and rebuilt, which could get better landscape allocation, it is very important to manage and restore ecology system of natural forest protection region in China by studying the method and approach of landscape ecology restoration. During the processing, following results and evolvement were gained in this paper.1. The topographic maps of study area were rectified, vector, modified errors and merged. The DEM in ARC/INFO was generated by the methods of linear and nonlinear interpolation. The accuracy of DEM was checked by the methods of spoint check and profile analysis. The results showed that: using point check, the accuracy of nonlinear interpolation was slightly higher than linear interpolation; using profile analysis, the errors of arbitrary direction was smaller than Y direction, the accuracy of nonlinear interpolation was higher at steep hill, but, the accuracy was very similar at flat region by using linear and nonlinear interpolation.2. With the support of ArcGIS, the slope and aspect were extracted and slice level was studied from DEM, the proportion of flat and steep region was larger, the proportion of iean region was smaller. The flat region was focused on the tong and parts of the river, the proportion of steep region was higher than that of fiat region, which showed that the study area was steep.3. During the processes of SPOT5 image, the data was orthorectified by using the DEM of the study area, the influence of the terrain was well eliminated. So it was very import to orthorectified the image by using DEM for forest land of complicated mountain region in China. Based on the property of remote sensor and the statistical characters of image, the quantitative conclusion could be drawn that the best multiple spectral bands combined result was 412 of SPOT5 by calculating the entropy, standard deviation and correlation coefficient in each band.4.With the support of AutoSync model in ERDAS IMAGE 9, the rectified SPOT5 of multiple spectral bands (10×10m) was used as referenced image to make match the geometric coordinate and edge match for TM data, which could improve the accuracy of TM greatly. The correlation coefficient and standard deviation were calculated and statistics, the best bands combined result could be ascertained by calculating the OIF. The supervised classification and accuracy check were made and the result of classification could be accepted.5. Different landscape type had different landscape pattern at the same elevation level. With the elevation increased, the change of landscape type and elevation was clearly shown. At different elevation level, three landscape types that had biggest area as flow: (1985a)bare land, alpine meadow, alpine shrub(I)-alpine meadow, alpine shrub, forest(Ⅱ)-forest, alpline meadow, alpine shrub (Ⅲ) forest, grassland, shrub (Ⅳ)-forest, grassland, shrub (Ⅴ) -forest, grassland, shrub (Ⅵ)(2005a):bare land, alpine meadow, alpine shrub(I)-alpine meadow, alpine shrub,forest(Ⅱ)- forest, alpine grassland, alpine shrub(Ⅲ)-forest, shrub, grassland(Ⅳ)-forest, grassland, shrub(Ⅴ) -forest, shrub, grassland(Ⅵ)6. With the elevation increased, the landscape diversity index and dominance index emerged on a certain distribution law. The landscape diversity index was biggest at 6th elevation level, but the smallest landscape diversity index was 4th elevation level, after that, The landscape diversity index increased a little, Generally, the landscape diversity index decreased with the elevation increased, on the contrary, landscape dominance index had adverse law with landscape diversity index.7. The landscape index of mean patch area, diversity index, dominance and patch density was selected to study the relationship among the landscape pattern and slope and aspect. The results showed that: the steep region had greater advantage of area proportion, the patch density and diversity were smallest, but the path mean area and landscape dominance were biggest; in fiat region, the patch density and diversity index were biggest and its landscape dominance and diversity index were smallest; in shady region, the patch density was smallest, patch mean area was biggest, the landscape dominance and diversity were much smaller, in sunny region, patch density and landscape dominance were biggest and patch mean area and diversity index were smallest.8. The relationship was analysed among the landscape spatial pattern and elevation, aspect and slope of reclassification. The results showed that: landscape distribution had certain correlation with elevation, aspect and slope, with the elevation and slope increased, the distribution of cropland (abandoned cropland) decreased, forest and shrub land were the main landscape type of shady steep slope, grassland was the main landscape type of sunny flat slope, but the difference of the landscape type distribution in different aspect was not obvious, It seemed that terrain had a certain influence on macro-distribution of landscape pattern. 9. The forest landscape type extracted by the grid sample and DEM was overlay, which could described the distribution pattern, geography and relative location of forest landscape in spatial scale. According to that results, the landscape element was analysed by using spatial pattern trend surface analysis. The formation, distribution law and the dynamic spatial pattern of forest landscape distribution pattern were studied, which could provide the theory for the restoration and sustainable of the natural forest ecology system of study area.10. The change of horizontal location made a certain influence on the landscape pattern evolution by using horizontal trend surface analysis, the difference of the trend surface of horizontal landscape element distribution in west-east and north-south direction was not obvious. In fact, the trend surface of horizontal distribution of landscape element could show that the terrain had control function on local landscape.11. In low elevation, the SI of shady slope was smaller and changed greatly, because the relative pure of broadleaf landscape distributed this region and belonged to the unstable landscape type, which was the earlier stage of landscape succession, its SI was smaller; the change of SI of sunny slope was stable, the mixed coniferous and broadleaf forest landscape distributed there and belonged to the important phase from the landscape succession process to climax pattern. In high elevation, the SI in shady slope was bigger, because the mixed coniferous forest landscape distributed here, its landscape construction was stable, the change of SI of sunny slope was great, because the amount of forest landscape of this region was litter. When the elevation greater than 3200 meter, With the aspect increased, the distribution shape of SI index was saddle-shapo, on the contrary, the distribution'shape of SI was"⌒"12. When the slope was below 20°, with the aspect increased, the relative SI was smaller, the distribution shape of SI was wave form, when the slope was between 20°and 60°, the distribution shape of SI was stable, when the slope was between60°and 90°,the SI increased gradually and changed greatly, the distribution shape of SI was"⌒"13. The spatial change of different land use type was studied by using matrix transfer in certain period in this paper. The result showed that: the forest and shrub land were stable landscape type of the study area, which kept the higher contribution rates of conversion-in and lower conversion-out, but the contribution rates of conversion-in of the forest was much higher than shrub, the contribution rates of conversion-in and conversion-out of the grassland were very high, but the contribution rates of conversion-in was greater than conversion-out. The contribution rates of conversion-in and conversion-out of other landscape was not changed a lot.14. The index of ecology and landscape structure was selected, with the support of spatial analysis of ArcGIS, the landscape ecology estimation was carried out by using AHP method and fuzzy analysis. The terrain factor(slice level, aspect and slope) and the estimation result were overlay. The result showed that: the forest land lafidscape ecology estimation index was bigger and got the biggest index at second elevation level; the forest land landscape ecology estimation index of shrub and grassland was second and third, the landscape ecology estimation index of barren land wasteland and barren hills was much smaller and the result of barren land was smallest at third elevation level.15. The distribution map of landscape pattern and ecology estimation was overlay with DEM, based on the land use, the landscape ecology classification was studied, the ecology process and restoration measure of landscape pattern of different terrain was studied in time and space, the landscape ecology restoration region was raised and rebuilt, which could explore the measure and method of natural forest landscape ecology restoration.
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