西双版纳勐养自然保护区土地利用对自然景观的影响

使用ARC/INFO和ARC/VIEW地理信息系统,对以1995年3月的卫星影像图、相关图件及数据为基础的图形数据库进行分析,研究了土地利用对勐养自然保护区自然景观的影响.结果表明,土地利用使季节雨林生境的异质性最高(多样性指数H为2.1759,优势度指数D为1.2831),季风常绿阔叶林异质性最小(H为1.2531,D为2.3318).该保护区总的人为干扰强度指数(HD)为0.1287,其中季节雨林生境受干扰最强烈,HD达0.8809.季风常绿阔叶林是保护区的优势植被(占总面积的78%),土地利用使其约12.36%(或10895hm₂)的面积被损坏.热带雨林(季节雨林、山地雨林和季雨林,占总面积的12%)是重点保护对象,土地利用使其损失了约19%(2557hm₂),是受到严重干扰的生境组分.耕地的斑块数量最多(占斑块总数的25.86%)而面积却很小(占总面积的2.2%),呈小块状散布在保护区里.人们因经营耕地而活动在保护区里,构成了大面积的干扰,使灌丛草地基本随着耕地散布在保护区里.要保护好西双版纳勐养自然保护区,必须以改善土地利用方式来控制耕地的扩散.

Impact of land use on natural landscapes in Mengyang Nature Reserve of Xishuangbanna.

Studies on the impact of land use on natural landscapes in Mengyang Nature Reserve of Xishuangbanna by the application of GIS ARC/INFO and ARC/VIEW showed that the land use resulted in the highest heterogeneity of the ecotope type of seasonal rainforest(Heterogeneity H 2.1759 and Dominance D 1.2831), and the lowest heterogeneity of the monsoon evergreen broad leaved forest (H 1.2531 and D 2.3318).The intensity index of human disturbance (HD) of the whole reserve was 0.1287, while that of the seasonal rainforest was 0.8809.Land use made 12.36% or 10895 hm 2 of monsoon evergreen broad leaved forest damaged, which was the dominated vegetation in the reserve, accounting for 78% of total area. It also made 19% or 2557 hm 2 of the tropical rainforest, the key protected object, damaged. The cultivated land was characterized by its numerous small patches (accounting for 25.86% of the total patches) and small area (accounting for 2.2% of the total area).A large area of disturbance was induced by human activities in the reserve, which made shrubs distributed in reserve, accompanying the cultivated land.It is suggested that the spreading of the cultivated land must be controlled by improving the land use styles in order to conserve the reserve well.