1990—2018 年新疆喀什噶尔河流域土地利用/覆被变化空间耦合及其生态效应.

[Objective ] The present paper discusses the land use change and ecological effect of Kaxgar River Basin from 1990 to 2018. [Method] Using the methods of land use dynamic index, land use intensity, land use gravity center, land use information entropy and equilibrium degree, combined with the value of ecosystem services, the land use change and its ecological effects in the Kashgar River Basin were analyzed from the perspective of spatial coupling. [Result] The land use of Kaxgar River Basin changed significantly from 1990 to 2018, and the cultivated land expanded rapidly, with a growth rate of 41. 95 % . The newly increased cultivated land mainly came from medium and low coverage grassland and unused land. The change of forestland was relatively stable and slightly increased. The grassland showed a decreasing trend, with an increase of 1967. 57 km² for high coverage grassland and a decrease of 4113. 02 km² for medium and low coverage grassland. Since 29 years, the area of water has decreased sharply, with a decrease of 53. 69%, and most of the area has been converted into unused land. The expansion of construction land was the most obvious, with a dynamic attitude of 21. 53 %, which was mainly transformed from cultivated land. In addition, the center of gravity of unused land gradually moved to the northwest and formed the spatial coupling relationship of 'desert-oasis-mountain' with the migration direction of cultivated land, water and grassland center of gravity. Information entropy and equilibrium degree showed a trend of rising first and then falling. With the acceleration of urbanization, the population continues to increase, the economic scale expands gradually, and the intensity of land use continues to increase. The ecosystem service value showed a state of first benefit and then loss under the main effect of grassland, waters and cultivated land changes, and there was a trend of continuous loss in the future. [ Conclusion] In the context of climate change, the continuous expansion of arable land, grassland degradation, and water scarcity have formed a spatial and temporal coupling, and the value of ecosystem services has gradually declined, posing a threat to the ecological security of basin. [ABSTRACT FROM AUTHOR]