煤炭开采对“矿-农”复合区农田质量影响评价

Evaluation of the impacts of coal mining on farmland quality in mine-agriculture regions in China

农田质量的内涵应包括本底质量、经济质量和生态环境质量3部分。煤炭开采导致农田严重受损,科学合理评价煤炭开采对矿-农复合区农田质量的影响,对制定区域土地复垦规划和综合整治有着重要的意义。以山西省泽州县长河流域为研究区,该研究首先建立了煤炭开采沉陷区农田质量评价的指标体系,选取农田自然质量、农业生产条件、区位条件、农田环境条件来表征农田质量,对并依据这些指标进行空间可视化,利用多因素加权求和的方法对农田质量进行综合评价。研究结果表明:与煤炭开采非扰动区相比,位于煤矿区井田边界内的农田自然质量、农业生产条件、区位条件、农田生态环境条件评价分值均较低;煤矿井田边界范围内的农田质量(平均值为0.37)低于非矿区农田(平均值为0.55)。应结合煤炭开采扰动影响区农田质量区域分布特点,制定科学合理的矿-农复合区土地复垦规划和土地综合整治方案。

Farmland quality refers to the ability of the land to perform agriculture functions,such as grain production,sustainable performance.The evaluation of farmland quality can include three aspects,background quality,economic quality and ecological environment quality.The indictor farmland quality provides the internal natural attributes,particularly on natural geographical conditions affected by social and economic input.Specifically,the“mining-agriculture”combined method can be widely engaged in agricultural production on the ground,while coal mining underground in Shanxi Province,China.Coal mining has caused serious damage to the farmland,where the quality of cultivated land has deteriorated,and thereby posed great threat on food security and social stability.Therefore,it is necessary to systematically evaluate the impact of coal mining on the quality of farmland in the mine-agricultural complex region,as well for the formulation of regional land reclamation plans.Taking the Changhe river basin in Zezhou County,Shanxi Province as the research area,four indexes were selected to characterize overall farmland quality,including natural quality of farmland,agricultural production conditions,location conditions,and farmland environmental conditions,according to the national standard"Regulations on Agricultural Land Grading and Classification".A specific index system was established to spatially visualize four indexes using the geographic information technology,ArcGIS.A multi-factor weighted algorithm was used to analyze the spatial distribution of each index,and to obtain comprehensive evaluation for the quality of farmland,particularly on coal mining subsidence areas.The results show that the constructed index system of farmland quality can be suitable for the“mine-agriculture”compound regions,reflecting the farmland status of the target areas.The evaluation scores of farmland natural quality,agricultural production conditions,location conditions,and farmland eco-environmental conditions were low in the undisturbed area of coal mining.The farmland quality within the boundary of the coal mine field(average 0.37)was much lower than that of non-mining farmland(average 0.55).It infers that coal mining can affect independent indicators,such as natural quality,economic quality and farmland environmental quality,and ultimately lead to a serious decline in the fertility of farmland at the regional level.The main reason is that the underground coal mining can destroy the topography on the ground,thereby result in soil nutrients loss,broken plots,ground subsidence of roads,and the discharge of mining pollutants at high levels of environmental pollution in local farmland.This finding can provide a theoretical basis to formulate a scientific and rational land-rehabilitation plan for the mine-agricultural complex regions,and comprehensive land improvement plans.