中国西部生态环境极其脆弱，煤炭资源开发与自然因素共同作用导致的矿区土地退化不容忽视，本文旨在揭示我国西部煤矿区土地退化的成因、程度、分布与趋势，为矿区土地退化防治与国土空间生态修复提供数据基础与决策依据。提出了煤矿区土地退化的概念，将煤矿区土地退化的直接因素划分为挖损、塌陷和压占，间接因素或外在表现划分为土壤侵蚀、植被退化与沙漠化或石漠化，结合实地调查并辅以高分辨率与高光谱遥感数据解译，提取了上述土地退化因素信息，并提出了土地退化外在表现的分级评价标准，进而构建了西部煤矿区土地退化的综合评价模型，对分布于黄土高原区、西南山地丘陵区、北方草原区和西北干旱区的12个重点煤矿区进行了土地退化信息提取、土地退化因素分析与土地退化综合评价。结果表明:① 影响井工煤矿的万吨塌陷率的因素有累计采厚、平均采深、煤层倾角及上覆岩性，影响露天煤矿的万吨损毁率的因素包括煤层厚度、剥离岩土厚度及其堆放方式。② 不同地域的矿区土地退化主要表现有所不同:黄土高原区为植被退化和土壤侵蚀，西南山地丘陵区为土壤侵蚀，北方草原区与西北干旱区植被退化、土壤侵蚀与沙漠化3者兼有。③ 矿山尺度的土地退化要比矿区尺度的更为剧烈，露天开采引起的土地退化要强于井工开采;矿区尺度的土地退化程度与煤炭资源开发强度(用煤矿扰动面积与矿区总面积之比表示)有关，开发强度越大，矿区土地退化程度越严重，而土地退化程度与开发强度并不呈正比，它还与矿区的生态脆弱性或承载力有关。因此,不同区域、不同采煤方法造成的土地退化形式及退化程度不一，因此需要采取不同的修复策略;为防止过度土地退化，需要根据矿区生态承载力确定合适的开发强度。

The ecological environment in western China is extremely fragile. The land degradation caused by coal re- source exploitation and natural factors cannot be ignored in Coal Mine Area ( CMA). This paper aims to reveal the causes,degree,distribution and trend of land degradation in CMAs in western China,and to provide basis for land deg- radation prevention and land space ecological restoration in CMAs. The concept of land degradation in CMAa is proposed,and the affecting factors are categorized into direct and indirect factors (or external manifestations). Direct fac- tors include excavation,occupation,and subsidence. Indirect factors include soil erosion,vegetation degradation,and desertification or stony desertification. These land degradation factors are obtained by combining field survey data and supplementary interpretation of high-resolution and hyperspectral remote sensing data. Moreover,a comprehensive eval- uation model for land degradation in western CMA is constructed based on the grading evaluation criteria for the indi- rect factors of land degradation. Finally,an empirical study was carried out on 12 key CMAs in the Loess Plateau Re- gion (LPR),Southwest Mountain and Hilly Region ( SMHR),Northern Steppe Region ( NSR) and Northwest Arid Region (NAR). The results show that:① the subsidence rate of per 10 000 tons is mainly affected by factors such as mining thickness,burial depth,dip angle and overlying lithology,while the damage rate of per 10 000 tons is mainly af- fected by factors including coal seam thickness,stripped rock and soil thickness,and rock and soil stacking methods. ② Different regions have different main manifestations of land degradation. Among them,LPR is vegetation degradation and soil erosion,SMHR is soil erosion,while NSR and NAR are vegetation degradation,soil erosion,and desertifica- tion. ③ The land degradation of mine-scale is far more severe than CMA-scale,and the impact open-pit mining is more severe than underground mining. In addition,the degree of land degradation on the CMA scale is related to the Coal Resource Development Intensity (Referred to as CRDI,expressed as the ratio of the disturbance area of the coal mine to the total area of the CMA). Among them,the greater the CRDI,the more severe the land degradation in the mining area. However,the degree of land degradation is not directly proportional to CRDI,and it is also related to the ecologi- cal vulnerability or carrying capacity of the CMA. In conclusion,as the forms and degrees of land degradation are dif- ferent due to diverse methods of coal mining in different regions,it requires to take corresponding stategies of land res- toration. In order to prevent the excessive land degradation,it’s necessary to determine the rational exploitation inten- sity according to the ecological carrying capacity of CMAs.

1 方法

    1.1 西部重点煤矿区土地损毁状况信息提取方法

    1.2 西部重点煤矿区土地退化信息提取

    1.3 西部重点煤矿区土地退化综合评价

2 结果与分析讨论

    2.1 西部重点煤矿区土地损毁结果分析

    2.2 西部重点煤矿区土地退化表现分析

    2.3 西部重点煤矿区土地退化的影响因素分析

    2.4 西部煤矿区土地退化综合评价

    2.5 露天开采规模对矿区土地退化的影响

3 结论