Karst rocky desertification is one of the major ecological and environmental problems that threaten the sustainable development of southwestern China. It is caused by irrational and intensive land-use patterns in karst geo-ecological environment. Therefore, it is vital to identify how human forces work on this degraded environment. Based on the soil erosion information in 2000 and remote sensing images of Guanling County collected in 2000 and 2007, four grades of karst rocky desertification data in 14 villages of Guanling County were extracted. Impacts of population, affluence, and other human forces on karst rocky desertification were analyzed using STIRPAT model. The results show that:1) Factors of population and affluence had strong influence on karst rocky desertification. In the STIRPAT model analysis, the population and affluence coefficients were positive, indicating that the increase in population and affluence would lead to more serious desertification. 2) Factors of farmer correlated with karst rocky desertification negatively, especially the way of viewing the relationship between people and nature, and the level of knowledge about rocky desertification. Government behavior was not a significant factor in this analysis. 3) The findings provide evidence that STIRPAT model can be used to analyze the relationship between human driving forces and rocky desertification.
On the basis of MSS and TM remote sensing data of 5 study periods during 1975-2002 as well as geographic data of Beijing City,evolution laws of landscape components and corresponding changes of the ecological environment are discussed through image processing and GIS analysis.The results show that structure of landscape eco-component changes greatly during the 27 study years,natural landscape components slightly increase,semi-natural landscape components drastically decline,humanistic landscape components increase fast and are mainly transformed from semi-landscape components,that is to say,urban construction land occupies a great number of farmland,and human interventions are serious;moreover,transformation among landscape components is also frequent in all study periods,semi-natural landscape components witness the largest transformation ratio,so semi-natural landscape components are a kind of relatively instable one in Beijing.In terms of eco-environment,natural landscape components within the city increase which is specifically demonstrated as increase of water,urban green space and vegetation coverage;compared with the data in 1975,it is obvious that eco-environment quality of Beijing is gradually improving,and urban environment quality also promoted.
