【作者】 景明；

【导师】 白中科； 师学义；

【作者基本信息】 中国地质大学（北京） ， 土地资源管理， 2014， 博士

【摘要】 本文以生态环境极度脆弱、人为干扰程度巨大,土地损毁极为严重的黄土区大型露天煤矿为研究对象,分析黄土区露天煤矿扰动地貌特征并对其进行分类；分析黄土区露天煤矿在“剥离-采掘-运输-排弃-整形-复垦”一体化工艺下的地貌演变机制及过程；选取地形指数,定量分析地貌重塑的时空演变规律；通过实地调查采样、分析化验、遥感解译及相关数据收集等,分析重塑地貌对土壤特性空间分异、植被立地条件、沟道河网时空变异及水灾风险性的影响；并在此基础上,进行地貌重塑优化研究,提出土地整形地貌重塑的建议,为黄土区大型露天煤矿地貌重塑、土壤重构、植被重建与生态重建提供一定的借鉴和参考,研究取得以下成果：宏观方面：(1)通过对黄土区及黄土区露天煤矿扰动地貌特征的分析,将黄土区露天煤矿扰动地貌划分为动态的开采地貌和趋于稳态的重塑地貌,其中开采地貌按开采过程分为剥离地貌、矿坑推进地貌和排弃地貌；重塑地貌按形态特征分为遗留矿坑地貌、外排土场地貌和内排土场地貌；(2)在总结黄土区大型露天煤矿区地貌演变的“剥-采-运-排-造-复”一体化工艺基础上,以平朔安家岭矿区为例,分析了矿区剥离开采的纵向工艺,运输排弃的横向过程,造地复垦的综合手段和地貌重塑的关键技术。地貌演变定量分析方面：(1)黄土区露天煤矿采、排、复地貌演变过程中地形因子指标呈现5种不同变化趋势；(2)确定黄土区大型露天煤矿地貌演变的2个主成分因子：起伏因子和扭曲因子；(3)将露天矿区地貌演变划分为四个阶段：矿坑与外排土场形成时期、矿坑推进与内排土场形成时期、内排土场推进时期、内排土场稳定时期,研究了不同阶段地形指标变化的差异性和阶段生态风险。对重塑地貌的响应方面;(1)重塑地貌是复垦土壤特性的重要决定因子,影响复垦重构土壤的发育特征和空间变异；不同坡位、坡度、坡向、复垦模式下的土壤特性存在显著差异；土壤水分和全氮与复垦因子、地形指数及遥感指数间存在较好的相关性,而土壤容重、有机质、全磷、全钾相关性低于预期值；运用回归克里格预测法进行了复垦土壤空间特性预测优化,提高了回归预测精度。(2)重塑地貌对植被立地条件、植被修复发育有较强影响,且不同的立地类型决定了植被恢复的难易程度、植被的配置类型及演替规律。其中,平台厚层黄土型、边坡土质中／下部坡型具有良好的立地条件,有利于植被恢复；将立地类型划分为平台、边坡2个立地小区：平台小区化分为9个立地类型组、13个立地类型；边坡小区化分为9个立地类型组、20个立地类型,为排土场立地条件改良、植被修复及生态恢复提供依据。(3)基于黄土区大型露天煤矿尺度提取河网沟道时,选取DEM分辨率为5m,汇流能力阂值为5000较为适宜；经过1990年与2013年水文地貌对比发现,剧烈扰动后沟道水文形态特征发生巨大改变,自相似性消失,而且汇水线密度和复杂度均降低,流域高差和坡降均增加,水文地貌整体呈单一化趋势；水灾风险性评价在未扰动前淹没指数分级明显,湿度指数和截留指数大小分布均匀,而扰动后三者均发生巨大改变,正负地形差别愈发明显,裸地、坡地增多,淹没指数分级分布不规律,湿度指数分布不均,截留指数总体降低,加大了矿区水灾的风险性和不确定性。地貌重塑优化方面：矿区仿自然地貌重塑是一个点、线布置到面的整体塑造过程,通过子流域和沟道的规划和设计、原地貌参数的提取和模型构建参数的优化,利用GeofluvTM模型构建仿自然地貌,使传统的平台-边坡-平台的设计,被凹形缓坡代替；传统的梯田式拾阶而下地貌,被弯曲式缓坡而下所代替；地貌由单一变成多样且多组合,由不考虑与周围景观协调的大型人工堆垫体变成与周围相互衔接的仿自然景观；沟道河网也进一步优化演变成一种蜿蜒自然的模式,沟道稳定性提高、水流冲击降低,最大程度的保证了汇流安全。更多还原

【Abstract】 This paper summarized and classified the morphologic characteristics of open-pit coal mine in loess area through the research about the extremely fragile ecological en vironment, the huge human disturbance, and the seriously damaged land in the giantc oal mine, analyzed the mechanism and process of landform evolution in the integrated project, which consists of peeling, mining, transportation, dumping and reclamation, selected topographic index, quantificationally analyzed the space-time evolution laws about topography rebuilding, and then analyzed the impact on spatial variation of soil, site conditions of vegetations, variation of river channels and the corresponding hazar d through field survey sampling, laboratory analysis, remote sensing interpretation an d literature and related data collection, analysis remodeling spatial variation of soil to pography, vegetation site conditions, at last, put forward topography optimization rem odeling and suggestions for loess landform reshaping large surface area as the referen ce of loess landform rebuilding, soil reconstruction, revegetation and ecological establ ishment in the future, and got the following results:Macroscopic results were that open-pit coal mining landform is classified into dynamic mining landform, which consists of the stripping topography, the marching pit topography and the dumping topography, and recontruced landform becoming steady, which consists of the remaining pit topography, waste-dump topography and inner spoil dump topography, through analyzing the characteristics of disturbed topography on the loess area, and analyzed the longitudinal process of peeling and mining, transverse process of transportation and dumping, methods of reclamation and technology of landform reconstruction on open-pit coal mine in the Pingshuo mining area, through summarized the integration process, which consists of peeling, mining, transportation, dump, shaping and reclamation in the open-pit mines in loess area.The results of quantitative analysis of morphological evolution shows, that the process of mining, casting, reclamation in the large opencast mine on loess hilly region presents five kinds of trends; that there are two new single indicators of terrain evolution, fluctuation factors and distortion factors, whose contribution rate is93.94%, and their principal component values has been calculated; and that the opencast mining area landform evolution has been divided into four stages:mine pit and external dump forming, pit advancing and inner dump forming, pit disappearing and inner dump advancing and inner dump stabilizing, which reveals the terrain indicators’difference of different stages and phased ecological risk.The impact of remodeling topography:Reshaped landform, which is an important factor for reclaimed soil properties in large opencast coal mine in loess area, affects development characteristics and spatial variability of reclaimed soil;the characteristics of reclaimed soil in different slope positions, or different slope gradients, or different slope aspects, or different vegetation restoration patterns were significantly different; soil moisture content’s and total nitrogen’s correlations with vegetation restoration patterns, reshaped landform and remote sensing indexes are good, but volume weight of soil’s, organic matter’s, total phosphorus’s, total potassium’s are poor; through regression Kriging method,resuits of regression prediction of soil moisture content, organic matter, total nitrogen and total phosphorus are good, and then the results’residual errors are reduced.Reshaped landform has a strong impact on vegetation site conditions, restoration and development. Different site types determines the difficulty of vegetation restoration, vegetation configuration type and succession law. Among them, a thick layer of loess platform type, slope soil medium/lower part of the slope type have good site conditions to vegetation restoration; The study area was eventually divided into2site area:platform and slope; platform area was classified into9site type groups and13site types, while slope area into9site type groups and20site types. This provided basis for the improvement of mine site conditions, vegetation restoration and maintenance as well as the local ecosystem recovery.When getting the channels in the open-pit coal mines on loess area through DEM,the appropriate resolution ratio and threshold value of catchment are respectively5m and5000. Through comparing the hydrological landform in1990 with that in2013, results that after severe disturbance in mining area, hydrological characteristics changed greatly, which leads channels’ self-similarity disappear, and the landform integrally has a simplification trend, which is that density and complexity of catchment lines reduced, and elevation difference and slope of drainage basin increased.Flood index has obvious hierarchy before mining disturbance, and humidity index and intercept index both have homogeneous distribution, but all three changed greatly after disturbance, which shows that flood index has no hierarchy, humidity index has uneven distribution and intercept index reduce integrally, and the flood risk index increases.Through planning and design of drainage basins and channels, extraction of original geomorphic parameters and optimizing parameters of constructing model, GeoFluvTM constructed a model imitated the natural landform. The design of the model is a constructing process of from points, lines to surface, traditional design of platform-slope-platform is replaced by concave gentle slope, traditional landform, which has ladders, is replaced by deviously gentle slople, landform changed from single to multiple, and the dump that is inharmonious with surrounding is replaced by imitated-nature landform which is connected with surrounding. Through construction of landform in GeoFluvTM, the drainage basins, channels and hillslopes would be tending towards stability, and the channels would become wriggle, which slow down the speed of stream, and incease stability of channels.更多还原