毛乌素沙地煤矿开采对植被景观的影响

毛乌素沙地气候干燥,水资源短缺,生态环境十分脆弱,对各种人为扰动极为敏感。该地区煤炭资源的开采势必会增加当地环境负担,使得生态环境恶化。以陕西省神木县大保当煤矿为例,通过实地调查,在查明自然植被种类、类型和分布的基础上,借助地理信息系统技术与地表沉陷预测模型,对煤矿开采造成的植被景观格局变化进行了预测,并分析了斑块数、形状指数、多样性指数等指标。结果表明,煤矿开采后矿区景观破碎度上升,斑块形状复杂化,景观异质性降低,植被生物量减少。矿区植被类型发生变化,原先以叉子圆柏(Sabina vulgaris)、北沙柳(Salix psammophila)、斜茎黄耆(Astragalus adsurgens)为优势种的灌木丛向以黑沙蒿(Artemisia ordosica)为优势种的灌草丛转化。从矿区整体变化程度来看,煤矿开采对区域自然生态系统存在一定的干扰,但未造成其根本性改变,自然生态系统仍存在一定的恢复和调控能力,应采取一系列生物与工程措施引导矿区生态环境向可持续方向发展。

Impacts of Coal Mining on Vegetation Landscape in Mu Us Sandland

Mu Us sandland with dry climate, scarce water, and fragile ecological environment, is very sensitive to all kinds of anthropogenic disturbances. Coal Mining resources in this region is bound to increase the burden on local environment, and make the ecological environment worse. Taking Dabaodang coal mine as an example, the number of patches, shape index, diversity index and other indicators were analyzed through field investigation, to find out the type and distribution of natural vegetation, using geographic information system technology and surface subsidence prediction model, and vegetation landscape pattern change caused by coal mining was predicted. The results showed that after coal mining, the landscape fragmentation increased, patch shape was complexitied, the landscape heterogeneity decreased, and the vegetation biomass reduced. The vegetation types changed. Bushes originally had Sabina vulgaris, Salix psammophila, Astragalus adsurgens as the dominant species of succeed to shrubs which was dominated by species Artemisia ordosica. From the change of whole mining area, there are some disturbance of coal mining to the natural ecological system, but was not cause the radical change, the natural ecological system still had certain recovery and control ability. A series of biological and engineering measures should be taken to promote ecological environment of the mining area to the direction of sustainable development.