Wang Xikai, Peng Suping, He Yunlan
State Key Labortaory for Fine Exploration and Intelligent Development of Coal Resources, China University of Mining and Technology (Beijing), Beijing 100083, China; College of Geoscience and Surveying Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China.
State Key Labortaory for Fine Exploration and Intelligent Development of Coal Resources, China University of Mining and Technology (Beijing), Beijing 100083, China.
Sci Total Environ. 2024 Nov 15;951:175831. doi: 10.1016/j.scitotenv.2024.175831. Epub 2024 Aug 26.
The Shendong mining area is the largest coal production base in China. However, the area is dry and water scarce, and the ecological environment is fragile. Large scale mining of shallow and thick coal seam in mining area may affect surface moisture and threaten surface ecological security. In order to understand the change of soil moisture in subsidence area. The evaporation loss rate of undisturbed and subsidence soil in mining area was estimated by using water stable isotope technique. The soil particle size and moisture of undisturbed and subsidence soil were compared. The results showed that the soil particle size did not change significantly in the subsidence area, but the continuity of soil structure changed. The evaporation loss rate of soil in subsidence area is about 15 % lower than that of undisturbed soil, and the soil moisture of soil in subsidence area is about 10 % higher than that of undisturbed soil. Further, the Craig-Gordon model is more accurate than the Rayleigh model in estimating the evaporation loss of soil moisture. Our work showed that the soil structure of coal mining subsidence area becomes much looser and the loose cover formed by the surface soil is the main reason for the reduction of soil moisture evaporation. The significant increase of soil moisture will be beneficial to plant recovery and growth, and lay a water foundation for ecological self-restoration in subsidence area. This study is helpful to understand the influence of coal mining subsidence on soil and surface hydrology in arid and semi-arid areas, and has important significance for optimizing and improving the ecological reclamation model of mining areas in western China.
神东矿区是中国最大的煤炭生产基地。然而，该地区干旱缺水，生态环境脆弱。矿区浅埋厚煤层的大规模开采可能会影响地表水分，威胁地表生态安全。为了解沉陷区土壤水分的变化情况，利用水稳定同位素技术估算了矿区未扰动土壤和沉陷土壤的蒸发损失率，并比较了未扰动土壤和沉陷土壤的粒径及水分情况。结果表明，沉陷区土壤粒径变化不显著，但土壤结构的连续性发生了变化。沉陷区土壤的蒸发损失率比未扰动土壤低约15%，沉陷区土壤的含水量比未扰动土壤高约10%。此外，在估算土壤水分蒸发损失方面，克雷格 - 戈登模型比瑞利模型更准确。我们的研究表明，采煤沉陷区的土壤结构变得更加疏松，表层土壤形成的松散覆盖层是土壤水分蒸发减少的主要原因。土壤水分的显著增加将有利于植物的恢复和生长，为沉陷区的生态自我修复奠定水分基础。本研究有助于了解干旱半干旱地区采煤沉陷对土壤和地表水文学的影响，对优化和改进中国西部矿区的生态复垦模式具有重要意义。
