黄土区大型露天煤矿排土场微地形塑造及其生态水文响应研究

As one of the most important mainstay industries in energy market, opencast coal mines are primarily located in the vulnerable Loess Plateau of northwestern China. Opencast mining is an efficient and cost-effective mode for the exploitation of mineral resources. However, this modern mining technology can give rise to a large impact on the surrounding landscape by permanently eliminating vegetation and altering topography, soils and subsurface geological structures. The soils of platform are severely compacted and the rocks and soils of slop are loose in large-scale dumps resulted from opencast mining, and the rainfall is centralized in this area; which result in accelerated runoff and soil erosion compared to the undisturbed natural surfaces. Previous research results showed that reclaimed soil erosion control is unable to be obtained good results using traditional "grading confluence, concentrated drainage" mode. If the larger modification is made on reshaping landforms, it will generate second earth moving and a substantial increase in the cost of land reclamation and water and soil conservation. Therefore, the idea of dispersing runoff and storing water instead of traditional draining off water is introduced in this study, and micro topography shaping method will be employed to solve the problem of increasing soil and water loss in the process of large artificial piled landform reshaping and to achieve the control of soil erosion and efficient use of limited water resources. Antaibao opencast coalmine in Shanxi province will be selected as research area. The change law in water infiltration and runoff in platform of large mechanical compaction and slop of loose soil, and the effects of different micro topography shaping modes of slope and platform on vegetation restoration and the eco-hydrological process of reclaimed soil will be studies in this study. The relationship among topography shaping, soil properties, vegetation restoration, and hydrological response in platform and slope of dumps will be characterized. This study can provide a scientific reference for land reclamation and soil and water conservation in large-scale opencast coalmine of Loess Plateau area.

黄土区露天煤矿开采形成了大量的大型人工堆垫地貌排土场，这些排土场平台土壤压实严重、边坡岩土松散。同时，本区域降雨集中，致使人工再造地貌土壤侵蚀加剧。已有研究表明，用传统的“分级汇流、集中排水”思路进行排土场复垦土壤侵蚀控制往往不能取得较好的效果。若对人工再造地貌进行较大改造，势必会造成“二次倒土”，大幅增加土地复垦与水土保持成本。为此本研究突破传统水土保持模式，从“分散径流、以蓄代排”的思路出发，选择山西平朔安太堡大型露天煤矿，引入微地形塑造方法解决大型人工堆垫地貌再造过程中水土流失加剧的问题，通过研究排土场平台和边坡不同微地形改造方式下土壤水分入渗和地表径流变化规律、分析不同微地形塑造方式对植被恢复及其水文效应的影响程度与作用机制、建立排土场边坡平台“地形塑造—土壤特性—植被恢复—水文效应”之间的定量表达关系，以期为黄土区大型露天煤排土场土地复垦与水土保持提供科学支撑。

黄土区露天煤矿开采形成了大量的大型人工堆垫地貌排土场，这些排土场平台土壤压实严重、边 坡岩土松散。同时，本区域降雨集中，致使人工再造地貌土壤侵蚀加剧。本研究突破传统水土保持模式，从“分散径流、以蓄代排”的思路出发，选择山西平朔安太堡大型露天煤矿，引入微地形塑造方法解决大型人工堆垫地貌再造过程中水土流失加剧的问题，通过室内模拟与田间小区试验研究了排土场平台和边坡不同微地形改造方式下土壤水分入渗和地表径流变化规律、分析了不同微地形塑造方式对植被恢复及其水文效应的影响程度与作用机制、建立了排土场边坡平台“地形塑造—土壤特性—植被恢复—水文效应 ”之间的定量表达关系，提出了黄土区大型露天煤矿排土场微地形塑造与植被配置控制岩土侵蚀的最优方案。研究发现微地形塑造具有较好的露天煤矿排土场岩土侵蚀控制效果，考虑微地形整地措施的自然、经济和技术综合效益，治理水土流失可以优选挡水埂和水平沟3m布设方案；如果着重考虑实际施工以及造价等因素，挡水埂和水平沟5m、畦地和水平沟3m布设方案可行性也较大。通过研究发表SCI/SSCI期刊论文15篇、CSCD期刊论文1篇，授权发明专利1项，培养博士生3名、硕士生9名。相关研究成果可为黄土区大型露天煤排土场土地复垦与水土保持提供科学支撑，本研究提出的排土场微地形重塑技术可在黄土高原区以及内蒙古草原区推广应用，具有广阔的推广应用前景。