典型煤粮复合区采煤沉陷积水区域时空演变特征与驱动力

Temporal and spatial evolution characteristics and driving forces of coal mining subsidence waterlogging area in typical overlapped area of coal-crop

采煤沉陷积水是高潜水位煤粮复合区的主要生态破坏特征,开展沉陷积水区域时空演变特征与驱动机制研究对于煤粮复合区水土资源优化配置与土地复垦具有重要意义。为揭示煤粮复合区采煤沉陷积水区域的时空演变特征与驱动机制,以典型煤粮复合区永城矿区为研究区,利用源自Landsat图像的1990—2020年中国30 m分辨率土地覆盖数据,使用ArcGIS软件中的按掩膜提取和按属性提取等功能提取不同年份水体分布信息,对比分析不同年份永城矿区水体面积变化及空间分布信息,从而揭示永城矿区长时序采煤沉陷积水区域面积时空演变特征。基于煤炭开采沉陷过程,探讨开采沉陷与地下水位及地表积水的耦合关系,结合煤炭开采、降水量、地下水位等因素分析采煤沉陷积水区域时空演变的驱动机制。研究结果表明,1990—2020年永城矿区水体面积增加8.2332km^(2),其中,1990—2000年变化幅度较小,2000年后煤炭井工开采沉陷累积效应显现,2000—2005年和2010—2015年年均增长率较高,分别为12.8213%和10.1412%;积水区域扩张部分主要分布在永城矿区中部、西南部、东南部和东部;煤炭井工开采是水体面积增加的主要驱动力,决定了采煤沉陷区水域的空间分布范围和扩展方向;地下水位和降雨量则在一定程度上影响了采煤沉陷区水域分布范围;地质结构及生态修复工程促进了采煤沉陷区积水区域增加。通过研究典型采煤沉陷积水区域长时序演变特征及驱动机制,为高潜水位煤粮复合区土地资源可持续利用与生态修复提供科学依据。

Coal mining subsidence waterlogging is the main ecological damage characteristic in overlapped area of coal-crop with high underground water level,it is of great significance to study the temporal and spatial evolution characteristics and driving mechanism of mining subsidence waterlogging area for optimal allocation of water and soil resources and land reclamation in overlapped area of coal-crop.Aiming to reveal the temporal and spatial evolution characteristics and driving mechanism of the subsidence waterlogging area in the overlapped area of coal-crop,Yongcheng Mining Area,a typical overlapped area of coal-crop,is selected as the research area,and the functions of ArcGIS software such as mask extraction and attribute extraction are used to extract waterlogging distribution information using the 30 m resolution land cover data of China from 1990 to 2020 from Landsat images.The variation and spatial distribution of waterlogging area in Yongcheng Mining Area in different years are compared and analyzed,thus the long time series evolution characteristics of coal subsidence waterlogging area in Yongcheng Mining Area is revealed.Based on coal mining subsidence process,the coupling relationship between mining subsidence and groundwater level and surface waterlogging is discussed,and the driving mechanism of temporal and spatial evolution of coal subsidence waterlogging area in combination with factors such as coal mining,precipitation and groundwater level is analyzed.The results show that the water body area of Yongcheng Mining Area increased by 8.2332 km^(2) from 1990 to 2020,and the variation range is small during the period of 1990-2000,however,the mining subsidence accumulative effect appeared after 2000,and the average annual growth rates of 2000-2005 and 2010-2015 are 12.8213% and 10.1412%,respectively.The expansion part of the waterlogging area mainly distributes in the middle,southwest,southeast and east of Yongcheng Mining Area.Coal underground mining is the main driving force for the increase of waterlogging area,which determines the spatial distribution range and extension direction of waterlogging area in coal mining subsidence area.The groundwater level and rainfall affect the waterlogging area distribution range in the coal mining subsidence area to some extent.Geological structure and ecological restoration project promote the increase of waterlogging area in coal mining subsidence area.The long time series evolution characteristics and the analysis of driving factors of typical coal mining subsidence waterlogging area are comprehensively studied,which could provide scientific basis for the sustainable utilization of land resources and ecological restoration in the overlapped area of coal-crop with high underground water level.