流沙河流域土地利用与地形因子的关系

目的]以西双版纳傣族自治州的流沙河流域为例,对该流域土地利用与地形因子的关系进行研究,为流域土地利用规划提供科学依据。方法]采用分布指数和基于DEM数据提取的高程、坡度、坡向,分析该流域1976—2010年各地类在不同地形因子下的分布变化特征。结果]有林地在较高海拔,较大坡度,北坡区域占有优势;茶园主要分布在1 200~1 400m海拔的东坡和南坡,坡度对其分布影响较弱;橡胶园主要分布在水热条件较好的600~1 000m海拔,坡度较缓,东坡和南坡区域;建设用地主要分布在中低海拔,坡度较缓,无坡向的平地;轮歇地在1 000~1 600m的东坡和南坡占优,坡度对其分布影响较小;水田主要分布在中低海拔,缓坡,无坡向的平地。结论]流沙河流域有林地和传统耕地不断被开垦为橡胶园和茶园等经济种植园,橡胶种植有向高海拔、陡坡与北坡发展趋势,使有林地分布进一步破碎化。为维持该流域生态稳定性,应严格控制好经济作物的种植面积,保护好现存的热带森林。

Relationship Between Land Use and Topographic Factors in Liushahe Watershed

Objective] Taking Liushahe watershed in Xishuangbanna Dai Automomous Prefecture as a case study area, this study tries to investigate the relationship between land use and topography factors in order to provide scientific support for land use planning.Methods] We extracted elevation, slope and aspect from DEM data, combined with distribution index, we then analyzed the relationships between land use distribution and topography factors from 1976 to 2010.Results] Forest was dominant in higher elevations, steeper slope and north-facing aspects; Tea garden mainly distributed in elevation between 1200 and 1400 m on east and south-facing aspects, and the slope had weak effect on the distribution of tea garden; Rubber plantation mainly distributed at elevation of 600~1000 m on gentle slopes in east-facing and south-facing aspects with better hydrothermal conditions; Construction land was mainly located in the area at low altitude with flat and gentle slopes; Rotation land mainly distributed at elevation of 1000~1600 m, and had a maximum percentage in east-facing and south-facing slopes, and the slope had little restraints on the distribution of rotation land; Paddy field mainly distributed in the area with low altitude, flat and gentle slopes.Conclusion] Forest and traditional tillage has been reclaimed for rubber plantation and tea garden, and rubber plantation continuously expands to higher and steeper areas and in north-facing aspect.As a result, the forest has been fragmented. Therefore, the expansion of rubber plantations into forest must be controlled to ensure the ecological stability of the watersheds in this region.