Controlling and restoration models of complex degradation of vulnerable Karst ecosystem
喀斯特脆弱生态系统复合退化控制与重建模式

The Karst area located at the center of Guizhou Tableland in China is the largest world. The typical problems in this region are poor ecological environment and poverty, where hardly to be recovered or restored; it is one of the six most vulnerable ecosystems in China. karst ecosystem is a complex process which was characterized by intensive human activities vegetation as inducement acting on the fragile continuous Karst zone in the the degraded ecosystems are Degradation of the vulnerable as driving force and decreasing geological resources, as a consequence, land deteriorated and desert landscape appeared. In this study, a new model was established to simulate the complex degradation process of vulnerable karst ecosystem based on local human activities, natural environment and economic development by using degrees, community types, service and function of ecosystems, land degradation and poverty as indicators. interruption The model showed that there were four major stages dominating the complex degradation process which were vegetation decreasing, loss of service and function of ecosystem, degeneration of soil quality and rocky desertification. The processes of degradation and restoration of vulnerable karst ecosystem did not occur simultaneously, and there were no linear relationships between them and restoration process took much longer time and was more difficult. A controlling model was also established to prevent rocky desertification using the principles and methods of temporary restoration ecology and temporary management. Based on this model, 3 types of recovering and restoration patterns of ecological protection, open economic and bi-triple helix were set up according to rocky mountain area, semi-rocky mountain area and mountain and hilly region, respectively, which would be greatly helpful to boost the harmonious and sustainable development of ecology, economy and society in Karst areas.