Influence of ecological land change on wind erosion prevention service in arid area of northwest China from 1990 to 2015

摘要

As an important "buffer" to slow down the expansion of desertification, ecological land can provide wind erosion prevention service (WEPS), which is closely related to regional ecological security and human well-being. Previous studies have focused on the response of WEPS to land use change, to a certain extent, would easily cause uncertainties, where the same type can be influenced by different physical and anthropogenic factors and further alter the WEPS. To solve this problem, ecological land was defined from the main function of land in this paper as a new indicator, and the impact of ecological land change on WEPS was quantitatively measured. The results indicated the following: (1) During the period 1990-2015, the net area of ecological land reduced by 16,244 km(2) or 17.74%. All second-level types of ecological land experienced a decreasing trend. (2) The annual average WEPS rate in the Tarim Basin was 34.82%, which increased by 1.42% across the 25 year period. (3) The increase of WEPS was mainly attributed to the expansion of oasis and the transformation of second-level eco-logical land types from low vegetation coverage to high vegetation coverage. The transformation of ecological land to desert was the main reason for the deterioration in WEPS. In the period 1990-2015, the protection and effective management of ecological land improved the ecological environment and increased the surface shelter in some regions, which was conducive to the improvement in WEPS.