Influence Study Of Sites On Vegetation Coverage In Dumps And Gangue Fields Based On UAV Remote Sensing Technology

The Northwestern Arid Desert Regions in China is the northern sand-proof belt of "two screens and three belts" of China's ecological security pattern,with large coal bases such as Shendong and Ningdong,which is the basis of China's ecological security and energy security.With the increase of mining scale and intensity,the ecological security problem in mining area is increasingly serious,and the ecological restoration task is increasingly difficult.It is of great importance to explore the influence and correlation between the site and vegetation coverage of the dumps and gangue fields in the Northwestern Arid Desert Regions in China to guide the ecological restoration work and restore the ecological environment of the mining areas.This study toke two typical coal mining cities,Wuhai and Lingwu,in the Northwestern Arid Desert Regions in China as the research areas,and selected the local mine dumps and gangue fields that have carried out artificial vegetation restoration as research objects.UAV remote sensing technology,field survey and laboratory experiment were used to obtain soil,topography and vegetation coverage data,statistical methods were used to study the relationship between sites and vegetation coverage of dumps and gangue fields.The main results are as follows:(1)Based on UAV image and visible vegetation index,the method of quickly extracting vegetation coverage of mine dump slope is feasible,and the extraction accuracy is high.Among the common visible vegetation indexes,VDVI index has the best performance in the vegetation extraction of the dump slope in the study area.(2)The slope of reclaimed dumps and gangue fields is generally larger,the soil has the characteristics of sandy soil,and the physical and chemical properties of the soil are generally lower in Wuhai and Lingwu mining areas.But soil bulk density,total potassium content and other indicators were improved compared with the surrounding natural areas.The slope of the dumps in Wuhai mining area is 25-37 °,and the vegetation coverage of the dump slopes in Wuhai mining area is between10%-32%.The slope of gangue fields slope in Lingwu mining area is 20-34 °,and the vegetation coverage of the dump slopes in Lingwu mining area is between 20%-66%.(3)There is an obvious correlation between slope soil,topography and vegetation coverage of dumps and gangue fields in Wuhai and Lingwu mining areas,Vegetation coverage is positively correlated with soil nutrients and capillary porosity,and negatively correlated with slope.Total potassium and total nitrogen contents are the main site influencing factors of vegetation coverage in Wuhai mining area.Organic matter,total potassium and slope are the main site influencing factors of vegetation coverage in Lingwu mining area.(4)According to the comprehensive score and rank of site factors of dumps and gangue fields in Wuhai and Lingwu mining areas,and the principle that taking the dumps and gangue fields site close to natural condition as the suitable site type,combined with land reclamation quality control standards(TD/ t1036-2013),preliminary put forward that: In Wuhai mining area,the reasonable coverage range in the early stage of vegetation restoration is 15%-26% in west slope of the dump.In Lingwu mining area,the reasonable coverage range in the early stage of vegetation restoration is 15%-63% in north slope of gangue field,15%-59% in south slope of gangue field,18%-58% in west slope of gangue field.