黄土区大型露天矿排土场水土流失评价

Water and soil loss assessment of the dump in large opencast mine in loess area

运用专家分析法和层次分析法确定了黄土区大型露天矿排土场水土流失的评价因子,建立了排土场水土流失评价指标体系和评价模型,并据此对平朔安太堡露天矿南排土场不同复垦时期的水土流失危害进行评价.结果显示:南排土场未复垦、植被恢复初期(复垦1～3a)、植被恢复后期(复垦8～10a)的水土流失影响度综合评价指数分别为0 863,0 512,0 399,处于极严重、较严重、较轻微级别.复垦8～10a后南排土场水土流失危害程度比采后新造地降低了两个等级,但仍存在一定程度的水土流失.提高植被的有效覆盖度,优化植被配置模式是进一步降低南排土场水土流失危害的主要措施.

Soil erosion assessment indexes of the dump of large opencast coal mine were made by Delphic and AHP, and soil erosion assessment indexes system and water-soil safety evaluating model were established, which are applied to assess soil erosion of the south dump by the evaluating model: the assessment result is according with the outside experiments. The assessment indexes number of the 3 stages of newly-constructed, 1～3 a and 8～10 a of reclamation are 0.863,0.512 and 0.399,which belong to the 3 grades of very serious,serious and slighter. The south dump still exists soil erosion in certain degree. Increasing planting cover and modifying planting modes can further lower soil erosion endangering of the south dump.