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Sand desertification is a serious ecological and environmental problem in semiarid grassland areas; thus an accurate understanding of its causes and process mechanisms is of significance for grassland desertification control. With the popularization of remote sensing monitoring technology, most research has focused on analyzing the trends of grassland sand patches and their impact on regional desertification, whereas fewer studies have explored the mechanisms of grassland desertification development. This study analyzed the dynamic changes in grassland landscape in the Hulun Buir grassland of China via multiperiod high‐resolution remote sensing images from 1959 to 2020, and examined the morphological changes, erosion patterns, grain size characteristics and sediment compaction of two trough blowouts. Our study noted that under climate change and human activities, grassland desertification is becoming increasingly serious, and its main manifestation is the occurrence and expansion of blowouts. Changes in blowout morphologies indicate that the area of the deflation basin shows a state of continuous growth, whereas the area of the depositional lobe shows fluctuating changes, which could mean that the deflation basin may be a useful indicator of desertification. Based on a detailed analysis of both climate and grassland changes, we believe that human activities determine the occurrence of blowouts, and climatic conditions determine the expansion of blowouts and the desertification degree. The morphological changes of blowouts are related to the removal mode and erosion resistance of the grassland soil, and the rate of removal of the soil limits the rate of blowout expansion.

Aeolian desertification is a severe ecological and environmental problem in arid regions. Research on its spatio-temporal distribution, modelling and driving force is necessary to prevent the development of aeolian desertification. In this study, the Moltsog Dune Field in Mongolia and the Ujimqin Dune Field in China were selected as the study areas, as both contain dunes under similar physical conditions. Using

Aeolian desertification is a severe ecological and environmental problem in arid regions. Research on its temporal and spatial distribution, development model, and driving force is necessary to prevent the development of aeolian desertification. In this study, the Moltsog dune field in Mongolia and the Ujimqin dune field in China were selected as the study areas, as both contain dunes with similar natural conditions. Using Landsat data from 1988, 1995, 2002, 2009, 2016, and 2020, the spatial-temporal distribution and degree of development of aeolian desertification in the two dune fields over the past 30 years were compared. Two periods of high-resolution images were then used to compare the surface morphological changes induced by aeolian desertification in the dune fields. Climatic and socio-economic data of the same period were used to compare and analyze the causes of changes in aeolian desertification in these regions. The results show that: (1) Over 30 years, the degree and development rate of aeolian desertification in the Ujimqin dune field were generally higher than those in the Moltsog dune field, and the former had a high degree of fragmented aeolian desertification patches with an expanding range. (2) The main form of aeolian desertification is the reactivation of fixed dunes, which includes the development of blowouts on the flat grassland under the influence of human activities in the Ujimqin dune field. (3) The desertification in Moltsog is mainly affected by climatic factors, while that in Ujimqin is mainly affected by human activities. The latter is specifically affected by the high grazing intensity before 2000 and increased mining activities after 2000. These findings provide a reference for comparing the aeolian desertification process and meaningful information for preventing and managing aeolian desertification and enabling the sustainable development of dune fields in arid regions.

In order to study the correlation between the vegetation coverage of typical grassland and the thickness of chestnut calcium soil layer, three typical geomorphic types of Wuzhumuqin typical grassland in Inner Mongolia were selected as experimental plots. It uses 3S technology and the methods of landscape ecology and geostatistics to test the image data and field quadrat in the past three years. It closely combines vegetation ecology with soil environment, the relationship between soil characteristics and vegetation landscape, and makes a correlation analysis on the synergistic evolution of chestnut soil thickness. The relationship between chestnut soil thickness, soil water content, and vegetation coverage under three different geomorphic conditions was obtained. Based on the quantitative analysis of the temporal and spatial differences between the vegetation coverage of typical grassland and the thickness of chestnut soil, the spatial distribution patterns of different soil types are revealed. Based on Landsat 8 TM image data, this paper makes statistics of vegetation index (NDVI) at three test sites. The spatial overlap method and the actual observation data are abandoned for spatial interpolation, and the similarity conclusion is obtained. The study shows that among the three sample plots in 2021, except for the original wavy high flat sample plot whose natural environment has been greatly damaged, the correlation coefficient between chestnut calcium soil layer thickness and vegetation coverage in the other two sample plots is also significant in the significance of 0.01 or 0.05 (two-sided test). It shows that there is a very significant positive correlation between the thickness of chestnut calcium soil layer and the thickness of chestnut calcium soil layer. The purpose of this paper is to use hyperspectral images to classify different kinds of plants, so as to realize the monitoring of chestnut soil. It will provide rapid and dynamic technical support for desertification control in the future.