Improved desertification grading and fine-scale integration of land use and severity for monitoring and ecological restoration at desert margins

Abstract

Desertification remains a critical issue, particularly in desert fringe areas that are ecologically fragile and prone to desertification. This paper innovatively develops a more accurate desertification severity grading model for these areas and analyzes the desertification situation across different land cover types to improve existing control measures. An improved grading model based on feature space was constructed for Liaoning Province, and a random forest model was used to classify desertified land cover types. Combining these results with desertification severity provided fine-scale information. The results of the dynamic monitoring of desertification severity based on the projection distance model in MSAVI-DI (Modified Soil Adjusted Vegetation Index- Drought Index) feature space showed that the total area of desertification in the 2019 is 4930.28 km². Over the past decade, the total desertified area has decreased by 373.71 km². The fine-scale information analysis indicates that desertification management and ecological restoration should prioritize areas with more fragmented landscapes. Poorly managed and abandoned croplands are prone to further desertification, underscoring the importance of targeted management efforts. Overall, the study constructed a grading model of desertification severity for desert margins. At the same time, fine-scale information on desertification containing the severity of desertification and land cover type was obtained. This provides a more accurate basis for future desertification restoration.