关键词: 风沙区, 采煤沉陷区, 沉陷裂缝, 土壤养分, 矿区生态修复

Abstract: In order to explore the variation characteristics of soil nutrients in different slope positions of coal mining subsidence cracks in aeolian sand area,taking the coal mining subsidence slope of Lijiata Coal Mine in Ordos as the research object,the longitudinal variation law of soil nutrient indexes in different slope positions of coal mining subsidence slope and nonfracture zone was analyzed. The results showed that the soil indexes of coal mining subsidence slope increased from the top to the bottom of the slope,the soil water content at the top of the slope was maintained at 10. 61%,and the soil organic matter in the fracture zone was 28. 61% lower than that in the non-fracture zone. Compared with the non-fractured zone,the soil moisture content and soil organic matter in the fracture zone at the middle and bottom of the slope decreased by 7. 32%,102. 59% and 21. 76%,149. 06%,respectively. The soil available nutrients in the fracture zone increased by 0. 03% ~ 14. 00% compared with the non-fracture zone. The study results indicated that:the coal mining subsidence cracks caused by coal mining have different degrees of influence on soil nutrients. With the decrease of slope,the influence of subsidence cracks on soil nutrients gradually increases. The subsidence cracks accelerate the evapotranspiration of soil moisture and the decomposition rate of soil organic matter,so that the soil available nutrients are enriched in the surface soil of the cracks,which lays a theoretical and practical foundation for the soil improvement of coal mining subsidence and the ecological restoration of mining areas.

Key words: windy desert area,coal mining subsidence area,settlement crack,soil nutrient,ecological remediation of mining area