Change in rocky desertification and effect of socio-economic activities in Guizhou

Rocky desertification is one of the most severe ecological problems in China. It has accelerated environmental degradation, caused frequent soil erosion and natural disasters, threatened people's living environment and restricted social and economic development. Analysis of the factors driving rocky desertification can be used to determine the factor that control rocky desertification and support strategies to combat the desertification. Studies have mainly focused on the geological background, geomorphological characteristics, meteorological factors, ecological restoration and governance projects. However, these studies have fallen quantification of the related social and economic activities. Thus there is the lack of a deep insight into the impact of the changes in regional rocky desertification and socio-economic activities. Using Guizhou Province as a case study area, this paper used GIS, remote sensing and statistical techniques (including Arcgis, Recognition Development and SPSS) to analyze the relationship between those neglected variables at county scale. Based on the 2000 and 2011 karst-rock desertification distribution maps, dynamic changes in rocky desertification in Guizhou Province in 2000-2011 were analyzed. The impact of social economic activities on rock desertification in karst area of the province was analyzed to lay theoretical basis for subsequent works on rocky desertification. The main conclusions of the study were as follows:1) one quarter of the karst area in Guizhou Province was still affected by rocky desertification in 2011, the control of which was still an arduous task. Based on spatial distribution, rocky desertification in Guizhou Province was relatively severe in the west and south of the study area and relatively mild in the east and north. The area of rocky karst desertification in Guizhou Province was on the whole improving. Different classes of rocky desertification were violently transformed into the other. Mild karst rocky desertification occurred in most of the area where there was improvement in rocky desertification, but the task of restoring light, moderate, severe and extremely severe rocky karst desertification was still very arduous. It also suggested that not only was attention needed to restore light, moderate, severe and extremely severe rocky karst desertification, but also to protect against potential areas of no rocky karst desertification. 2) The correlation analysis to determine the factors driving rocky desertification showed that multiple factors (including population factors, socio-economic development, agricultural production activities, terrain slope and ecological engineering construction) were critical in the evolution of rocky desertification in the region. Agricultural activities had the most significant effect on rocky desertification, including the proportion of agricultural population, total agricultural output, cultivated land area per cap., cultivated land proportion in 15°-25° slope, cultivated land proportion at > 25° slope, karst proportion at 15°-25° slope, karst proportion at > 25° slope. The correlation coefficients for these factors with rocky desertification were 0.473, 0.425, 0.291, 0.288, 0.430, 0.338 and 0.334, respectively. The study of the impact of socio-economic activities on rocky desertification provided the required expertise on the control of rocky desertification in the region.