Study On The Change Of Entironment And The Landscape Pattern In Xishuangbanna District, LanCangJiang Watershed

Xishuangbanna district is located in the lower reaches of Lan Cang Jiang, whichis the last area that Lan Cang Jiang flows over China. And it has been famous for itsecological tourism area. So, its entironment is very importance. The issues ofentironment that it is facing have troubled all regions of Lan Cang Jiang watershedand the land area boundary in southland. Therefore, the paper takes Xishuangbannadistrict as the object and studies it as a whole drainage area. With the date provided byRS and GIS, as well as the DEM altitude data and other data, combining the methodsof landscape pattern, the entironment changes from 1988 to 2002 in Xishuangbannadistrict have been analyzed in two terms of soil erosion and landscape pattern. Theresult of study has valuable significance.The results have been shown as follows: (1) Base on the study of the actual soilerosion, at present the soil erosion areas in Xishuangbanna district is up toapproximated 30 percent, The main component part of soil erosion can be divided intolight, moderate, intense soil erosion. The soil erosion in west and south areas providedwith high density and high strength, but north and east areas have the contrarysituation. (2) According to the analysis of RS images in two periods, the area of soilerosion intension is in depressive status, but it ascends a little in recent years. Indecades of years, the soil erosions have happened with intensity change in about 11percent areas, and the change areas are focus on the south, east, southwest region, andthe soil erosion of the incremental acreage are mainly in moderate and intense level.(3) Base on the research of the landscape pattern, the landscape pattern in region ofinterest is in the situation that minority landscape has preponderance, and this renderthe asymmetry and complication of landscape are increased. In the conversion processto balance landscape pattern, some irrational pattern were came forth and brought badinfluence to entironment. The marked changes of landscape of Xishuangbanna districtare centralize in Lan Cang Jiang watershed and its branch area, and the change oflandscape pattern in drainage watershed influenced the circs of watershed area. (4)According to the two angles of entironment such as drainage area and landscapepattern, the entironment in Xishuangbanna district is stand in the transient state, and itcan establish a steady ecological system and benign entironment gradually byadjusting landscape structure, rational land utilization, regarding watershed factor,contour farming and so forth.