Analysis Of Dynamic Changes Of Vegetation Coverage And Driving Factors In Lingwu City,Ningxia

In this study,the 1999-2018 5th period Landsat TM/OLI remote sensing image of Lingwu City was used.Through ENVI5.3 and ArcGIS 10.2 software,the normalized vegetation index and pixel dichotomy model were used to invert 1999,2003,and 2008.The vegetation coverage in 2006,2013 and 2018 was studied.The spatial and temporal dynamics of vegetation coverage in Lingwu City from 1999 to 2018 were studied,and the driving mechanism was explored from both natural and social aspects.The reasons for the dynamic changes of vegetation in Lingwu City were discussed.Provide the basis for the change of coverage and the identification of influencing factors.The research results are as follows:(1)The average vegetation coverage in the 5th period of 1999-2018 in Lingwu City was 25%.The overall vegetation coverage was relatively low.The overall spatial distribution of vegetation coverage showed that the western region was higher than the eastern region,and the southern region was higher than the northern region.From 1999 to 2018,there was no significant change in the vegetation coverage in the western region,the vegetation coverage in the central region increased,and the vegetation coverage in the eastern region decreased slightly.(2)The change of vegetation coverage in Lingwu City from 1999 to 2018 showed a decrease first and then an increase,showing an overall increasing trend.Since 2009,the average annual vegetation coverage has shown an increasing trend,and the vegetation coverage has gradually increased.From 1999 to 2018,the degree of fluctuation between the extremely low vegetation coverage and the area of the low vegetation coverage was relatively large,of which 13.55%of the extremely low vegetation coverage was transferred to low vegetation coverage,and 15.91%of the low vegetation coverage was transferred to Medium and low vegetation coverage.(3)Natural factors in Lingwu City have a certain degree of influence on the distribution of vegetation coverage types.During 1999-2018,the vegetation coverage change was greatly disturbed by human factors.Coal mining activities will cause the vegetation coverage in the mining area and surrounding areas to decrease.In recent years,after vegetation restoration has been adopted,the vegetation coverage has increased.