| Rocky desertification is one of the important environmental problems the k arst area is facing in Southwest China,whose evolution process and driving m echanism analysis have always been the difficulties and hotspots in the related research fields.Grasping the spatial and temporal distribution of rocky desertifi cation in the region and changing characteristics to explore rocky desertification are discussed.Researching the relevant changes of the driving mechanism is o f great significance to the prevention and control of soil erosion,the improvem ent of the ecological environment,and the poverty-stricken areas.In this study,we selected Enshi City in the southwest of Hubei Province,where the geogra phical environment is relatively poor and the economic development is relativ ely lagging behind,and which is also a multi-ethnic community By using the remote sensing images of the research area 3?2007,2011,2015?,based on E NVI 5.1 Arc GIS10.2 and SPSS22.0data processing and analysis platform,usin g the transfer matrix,CA-Markov model,principal component analysis and gra y correlation analysis methods,characterize the rock desertification factors?veg etation coverage,bedrock contact?in Enshi City from 2007 to 2015,the chang ing law and driving mechanism of the type of rock desertification.Based on t he research,a series of analyses were carried out,to provide suggestions for c omprehensive management decisions of regional rock desertification.The results show as follows.?1?The vegetation coverage in Enshi City is dominated by higher vegetati on coverage?HFC,FFC?.The overall distribution is characterized by lower ve getation coverage in the central region and northeast region,and gradually incr eased vegetation coverage in the southwest and northwest regions.The vegetati on with high coverage is mainly concentrated in the southwest and southeast r egions.?2?During the three periods of 2007-2011,2011-2015 and 2007-2015,t he overall rock exposure rate of Enshi City showed a decreasing trend.Accord ing to the investigation of the administrative divisions of Enshi City,the areas where the increase exists are located in the central part of Enshi City?Tun B ao Township?,the north?Taiyanghe Township,Longfeng Town?and the south west?Bajiao Township and Shengjiaba Township?.?3?The distribution of rock y desertification in Enshi City is characterized by local zonal zone and scattere d distribution in other areas.Most areas with a high degree of rocky desertific ation are concentrated in the middle and northeast of the research area,and sc attered distribution is also found in the southern region.However,the overall d egree of rock desertification is relatively mild.The area of severe rock desertif ication type is relatively light,and the overall degree of rock desertification is mainly mild and moderate.?4?From 2007 to 2011,the proportion of stony de sertification getting better?16.36%?>getting worse?2.83%?.The area with fav orable transformation mainly lies in the middle and east and northeast of the r esearch area.From 2011 to 2015,rocky desertification improved?7.02%?>det eriorated?6.62%?.From 2007 to 2015,the rocky desertification type improved?15.90%?>deteriorated?1.98%?.the areas where the rocky desertification chan ged were the central and eastern regions(Sancha Township,CuijiaBa Town,S hadi Township,Xintang Township,etc.?5?The evolution process of latent roc ky desertification and mild rocky desertification is relatively fierce,with the maximum change rate of potential rock desertification reaching 85.35 km2/a fr om 2007 to 2011,and the highest change rate of mild rock desertification also reached 51.26km2/a from 2007 to 2011.?6?The CA-Markov model predicts various types of rock desertification data for 2037 in Enshi City.The non-rock y desertification types were 1941.85 km2,the potential rocky desertification wa s 1237.11 km2,the mild rocky desertification was 501.34 km2,the moderate ro cky desertification was 155.25 km2,and the severe rocky desertification was 60.44 km2.?7?The factors with high correlation of the overall rocky desertificati on type are X1 forest coverage?the average correlation is 0.913?,total cultivate d land resources at the end of X4?the average correlation is 0.916?,X111 agric ultural population density?the average correlation is 0.917?,indicators The low er total correlation degree of the system is the X2 garden area?the correlation mean is 0.468?and the slope farmland area above X9 25 degrees?the correlati on mean is 0.524?;the other driving index evaluation factors,the correlation m ean value are all above 0.6.Between 2007 and 2015,due to the implementation of various ecological restoration policies and comprehensive management projects in the evolution pr ocess of rock desertification in Enshi City,the regional rock desertification as a whole showed a state of mitigation and optimization.The analysis predicts t hat the degree of rocky desertification in Enshi will be improved and optimize d to a greater extent by 2037.Based on the change of rocky desertification,st atistical methods were used to analyze the correlation of various related driving factors in the region the driving mechanism of rocky desertification in the reg ion was explored,and the correlation degree of driving factors corresponding t o each type of rocky desertification was obtained.The extraction method of ro cky desertification provided in this paper is fast and efficient.The extracted m aps and data can provide a reference for regional research on rocky desertificat ion,and the conclusions drawn can provide scientific support for regional contr ol of rocky desertification. |
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