Effects of Land Use Change on the Ecosystem Services Value in the Dry-Hot Valley

The objective of the study reported here was to determine whether LANDSAT TM images could be used to quantify changes in land-use and ecosystem services in Yuanmou County. The sizes of six land use/land cover(LUCC) categories were estimated in Yuanmou County according to the LANDSAT TM images in the summer of 1986 and 2005. Coefficients published by Xie Gaodi and co-workers in 2003 were used to value changes in ecosystem services delivered by each land use/land cover category,and the ecosystem services sensitivity analysis was conducted to de-termine the effect of manipulating these coefficients on the estimated values. The im-portant results are summarized as followings. ① The estimated size of cultivated land,pasture land,water area and unused land decreased by 6.39%,1.35%,2.25% and 10.67% respectively between 1986 and 2005. By contrast,the estimated size of forest land and construction land increased by about 2.23% and 71.15% respectively between 1986 and 2005. ② The total ecosystem services value(EVS) of the study area in-creased from 2 142 132 609.46 yuan to 2 146 416 621.00 yuan,with the net increase of 4 284 011.54 yuan during the 20-year time period. ③ The coefficient sensitivity(CS) of the study are less than unity in all cases(CS ∧1) . This indicates that the total eco-system values estimated for the study area are relatively inelastic with respect to the ecosystem service coefficients. While this implies that our estimates are robust and the coefficient is reasonable,highly under or over valued coefficients can substantially affect the veracity of estimated changes in ecosystem service values overtime even when the CS are less than unity(CS ∧1) .