Abstract:
The gravel curtain layer, composed of soil crust and gravel, offers an important ecological barrier in desert mining area. Natural gravel curtain layers exhibit strong stability; however, large-scale mining disturbances have caused severe damage to the gravel curtain layer. This study was intended to reveal the wind erosion resistance of the gravel curtain layer. For this purpose, we collected samples from the gravel curtain layer in 5 mining areas in the Eastern Junggar Basin and conducted remote sensing analysis, wind tunnel experiments, and numerical experiments. The regional distribution features of the gravel curtain layer in the Eastern Junggar Basin were obtained, and the features of gravel cover in the natural the gravel curtain layer in this region were analyzed. We further revealed the law and mechanism of the in-fluence of gravel cover and cover type on wind erosion resistance and studied the mechanical and physico-chemical properties of soil crust, the quantitative relationship between the two was established. Our results showed that: ① The gravel curtain layer was widely distributed in the Eastern Junggar Basin, primarily in the northern parts of the Wucaiwan and Dajing mining areas. However, some regions have been damaged due to mining activities. ② Gravel cover was positively related to wind erosion resistance of the gravel curtain layer. For every increase in gravel cover by 15%, the wind erosion of soil was reduced by 10%−30%. At the same gravel cover of the desert pavement, the proportion of medium- and small-grained gravel was positively correlated to the wind erosion resistance. Compared with particle size distribution, gravel cover had a larger impact on wind erosion resistance. ③ The shear strength of soil crust in the gravel curtain layer was correlated to the physicochemical properties of soil. The physicochemical parameters of soil were ranked as follows in descending order of the correlation coefficient: clay content (0.946) > organic matter (0.894) > calcium carbonate (0.888) > moisture content (0.518) > silt content (0.312). Clay content has the most significant impact on the shear strength of soil crust, and it not only directly affects shear strength but also exerts indirect influence through calcium carbonate (
0.7741) and organic matter (
0.7733). ④ The terrain of the Eastern Junggar Basin slopes from low in the northwest to high in the southeast, and the distribution pattern of its soil properties is consistent with the topographical gradient of the region.