Study On Vegetation Community And Soil Seed Bank Of Opencast Coal Mine Dump In Loess Area

In this paper,the different recovery models of slope and platform of Wujiata mine dump in Ordos were studied by using field investigation and indoor germination experiment.The spatio-temporal distribution characteristics and relationship between vegetation community and soil seed bank in opencast coal mine dump in Loess area were studied systematically.The benefit and potential of different ecological restoration models were discussed.The main results achieved were as follows:(1)A total of 32 plant species belonging to 12 families and 22 genera and 13 species belonging to 6 families and 8 genera of vegetation communities and soil seed bank were counted under different slope restoration models respectively.Saliuge was more favorable to increase species diversity while artemisia island was more favorable to increase vegetation density and legume grass belt was more favorable to increase soil seed bank scale.The similarity between soil seed bank and vegetation community was 0.23—0.36.The effect of vegetation restoration of Artemisia sphaerocephala krasch was better than that of other restoration models while the community stability of saliug restoration model was higher.The storage of soil seed bank in the legume grass belt restoration model was large,which increased the driving potential of vegetation restoration.(2)There were 50 species of plants belonging to 16 families and 40 genera under different vegetation restoration models.There were 11 species belonging to 4 families and 9 genera in the soil seed bank.For the vegetation community,Robinia pseudoacacia forest species diversity was the highest,Hippophae rhamnoides forest density was the largest.The coverage of alfalfa planted for 6 years and the scale of soil seed bank were the largest.The similarity coefficient between plant community and soil seed bank was 0.24—0.67.The restoration model of Robinia pseudoacacia was beneficial to the stability of community and the benefit of vegetation restoration was better.Medicago Sativa and Ulmus pumila soil seed banks had large scale,which can increased the potential of vegetation restoration.(3)The species diversity of shrub community and soil seed bank was the best.The density of plant community and soil seed bank was the highest under grassland type,which could reach495.47 plants/m~2and 1422.91 seeds/m~2respectively.The shrub vegetation type is helpful to increase the community stability,and the grassland vegetation type has higher restoration benefit.Grassland and shrub vegetation are the main vegetation types in the construction of platform artificial vegetation.Therefore,for the vegetation restoration and reconstruction of the dumping slopes in the Aeolian Loess area can give priority to the salug restoration model,improve the vegetation restoration efficiency,and combine with the legume grass belt to enhance the vegetation restoration potential.The platform could consider constructing artificial vegetation restoration model with grass-shrub arrangement as the main part to protect community restoration potential and improve community diversity and stability,and could also consider introducing exogenous seed bank to enhance community restoration potential.There are 21 figures,14 tables and 118 references in this paper.