Abstract: 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/VIEWshowed 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 DHD) of the whole reserve was 0.1287, while that of the seasonal rainforest was 0.8809.Land use made 12.36% or 10895 hm² 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 hm² 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).Alarge 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.

Key words: Impact of land use, Human disturbance, Landscape change, Nature reserve, Xishuangbanna, soil phosphorus, semi-variance function, spatial variation., flooded area of the Yellow River, Kriging interpolation