关键词: 交叉敏感性, 克里雅绿洲, 生态系统服务价值, 土地利用类型转换

Abstract:

Land-use change is a major driver behind the loss of ecosystem services. In recent years, a great emphasis has been placed on the responsiveness of ecosystem services value to the land-use change, and the coefficient of sensitivity, as an important indicator, has been widely used for the assessment of this responsiveness. However, the limitation of sensitivity analysis, proposed by Kreuter et al, on this application has been neglected. In this paper, firstly, the reexamination was carried out for the conventional sensitivity analysis, and the concept of cross-sensitivity and its calculation was proposed on this basis, through which it was more intuitive to characterize the responsiveness of ecosystem services value to the mutual transformation between land use types. Secondly, a dynamic analysis was conducted using coefficient of cross- sensitivity for the responsiveness of ecosystem services value to the transformation among land use types in the Keriya Oasis in 1991, 2002 and 2011 respectively, noting the processes of land-use change, to which ecosystem services were increasingly sensitive, to provide a reference for land-use policy. The main conclusions were drawn as follows: 1) The categories of land-use transformations to which the ecosystem services showed sensitive were stable during the three time points 1991, 2002 and 2011, mainly concentrated on the conversions from the land-use types with high ecosystem functionality, i.e. wetland and water body, to the others which are large in size and poor in ecosystem service provision, i.e. desert and low- densitygrass. For example, 1% conversion from wetland to desert caused 4.15% loss in ecosystem service in 1991, and 4.45% loss in 2002; 1% transformation from water body to low-density-grass led to 1.16% and 1.30% loss in ecosystem service in 1991 and 2002. 2) As compared with 1991 and 2011, the cross-sensitivity coefficients generally increased in 2002, mainly due to the decrease in the size of wetlands and water area which exacerbated the ecological vulnerability of the study area, and as a result the value of ecosystem services showed greater sensitivity to such transformations. 3) The coefficient of cross- sensitivity for the transformation from wetlands and water body to arable land had been in a rising trend, and continued close to -1, indicating that the value of ecosystem services became more and more sensitive to the intensifying human activities.

Key words: cross- sensitivity, the Keriya Oasis, ecosystem services value, land- use transformation