Zhang Kai, Yang Kang, Wu Xingtong, Bai Lu, Zhao Jiangang, Zheng Xinhui
School of Chemical &Environmental Engineering, China University of Mining and Technology, Beijing 100083, China.
ACS Omega. 2022 May 23;7(22):18688-18698. doi: 10.1021/acsomega.2c01369. eCollection 2022 Jun 7.
The impact of coal mining subsidence on surface ecology involves the influence of several ecological elements such as water, soil, and vegetation, which is systematic and complex. Given the unclear understanding of the synergistic change patterns of the water-soil-vegetation ecological elements in the influence of coal mining in the west, this paper investigates the impact of coal mining on the surface ecology, especially the distribution of soil water content (SWC). In 2020, this study collected 3000 soil samples from 60 sampling points (at depth of 0-10 m) and tested the SWC. All samples come from three different temporal and spatial areas of coal mining subsidence in the desert mining area of Northwest China where soil types are mainly aridisols. At the same time, the interactions among deep SWC and surface soil physical and chemical properties, surface SWC and soil fertility, and pH were analyzed. The spatial variability of soil moisture is reflected by kriging interpolation, and SWC values at different depths are predicted as a basis for monitoring the environmental impact of different coal mining subsidence years. The research has shown that the ground subsidence leads to a decrease in SWC value and changes in surface soil pH, physical and chemical properties, and covering vegetation, which have occurred from the beginning of coal mining. The impact of coal mining on the SWC of the unsaturated zone is mainly at the depth of 0-6 m, where SWC is not directly related to the nutrient content of the surface soil. The overall settlement of the ground will stir up simultaneous decline in the quality of deep SWC and topsoil. The findings of this investigation suggest that changes in the soil structure caused by coal mining subsidence are the key factor in SWC loss. Timely monitoring and repairing 0-6 m ground fissures, as well as selecting shrubs on the surface is the best choice for the restoration of the ecological environment and prevention of soil erosion in this area.
煤炭开采沉陷对地表生态的影响涉及水、土壤、植被等多个生态要素，具有系统性和复杂性。鉴于西部煤炭开采影响下水-土-植被生态要素协同变化规律认识不清，本文研究煤炭开采对地表生态的影响，尤其关注土壤含水量（SWC）的分布。2020年，本研究从60个采样点（深度0 - 10米）采集了3000个土壤样本并测试了土壤含水量。所有样本均来自中国西北沙漠矿区煤炭开采沉陷的三个不同时空区域，这些区域土壤类型主要为干旱土。同时，分析了深层土壤含水量与表层土壤理化性质、表层土壤含水量与土壤肥力以及pH值之间的相互作用。通过克里金插值法反映土壤水分的空间变异性，并预测不同深度的土壤含水量值，作为监测不同煤炭开采沉陷年份环境影响的依据。研究表明，地面沉降导致土壤含水量值下降，以及表层土壤pH值、理化性质和覆盖植被发生变化，这些变化自煤炭开采开始就已出现。煤炭开采对非饱和带土壤含水量的影响主要在0 - 6米深度，该深度土壤含水量与表层土壤养分含量无直接关系。地面的整体沉降会引发深层土壤含水量和表层土壤质量的同步下降。本调查结果表明，煤炭开采沉陷引起的土壤结构变化是土壤含水量损失的关键因素。及时监测和修复0 - 6米的地面裂缝，以及在地表选择灌木是该地区生态环境恢复和防止土壤侵蚀的最佳选择。
