辽西北半干旱区土地退化遥感监测及其驱动力分析OA

[Objective]Utilizable land resources is scarce in semi-arid regions,systematic analysis of the spatiotemporal processes and influencing factors of land degradation is of highly significant for these ecologically fragile areas.[Method]Based on NDVI,meteorological data,land use data,ET,and NPP from 2000 to 2024,the water utilization efficiency(WUE)in the semi-arid region of Northwestern Liaoning was calculated.The spatiotemporal patterns of land degradation at different stages were analyzed using the WUE-NPP framework.Sen's slope estimator combined with the Mann-Kendall trend test and multiple stepwise regression were employed to reveal the dynamic changes in WUE and NPP,as well as their relationships with climate and human activities.[Results]The results indicate that from 2000 to 2024,WUE in Northwestern Liaoning showed an overall steady yet positive trend.Significantly increased areas were mainly concentrated in southern Fuxin City,while significantly decreased areas were primarily found in Chaoyang City and northeastern Fuxin City,with both categories accounting for comparable proportions.Land degradation across the study area has generally been mitigated,with restored land accounting for 27.19%of the total area,whereas degraded land accounted for only 2.02%,mainly distributed in Chaoyang City and southwestern Fuxin City,predominantly in the mid to late stages of degradation.[Conclusion]Comprehensive analysis of land degradation stages using WUE and NPP revealed that both climate and human activities play dominant roles in land degradation or restoration.In particular,the fragile natural environment of semi-arid regions and excessive human activities lacking effective policies and regulations have accelerated the process of land degradation.