The Ecosystem Service Function Value And Evaluation Analysis Of The Typical Rock-desertification Area Under The Human Intervention

Natural ecosystems are essential for the survival of mankind. With the development of science and the emergence of environment problems, fully understanding and properly evaluation of ecosystem function become an important research topic. Karst regions have special geologic background and landform environment. The bad ecological environment results in the more obvious regional conflict between human and land. The study and discuss on the composition and related evaluation of the regional ecosystem service function are particularly urgent and significant. Taking the typical karst valley of the southwestern rocky desertification area-Huajiang demonstration area as the study area, in view of the difficulty of data acquisition and the inefficiency of the evaluation method for the current ecosystem service value assessment, this paper utilizes technologies such as GIS which is efficient,has spatial expression and is convenient for management. Referring to the mature and the latest results from the academia, for the karst regions the paper establishes a set of ecosystem service function value assessment systems which is targeted, efficient, and easy to manage. The paper chooses a quantitative analysis for the intensity of human disturbance based on the landscape pattern, and through the spatial overlay analysis, the correlation between the intensity of human disturbance in the study area and the value of ecosystem service has been found. By study and analysis, conclusions are drawn as follows:(1)The total value of the study area in the three periods of ten years shows down first and then up. In 2000, 2005, and 2010, the total value was 202.6160 million yuan, 202.4579 million yuan, and 302.2240 million yuan respectively. The rate was 0.08%, 49.28%, and 49.16% respectively in 2000-2005, 2005-2010, and 2000-2010. On the whole, the spatial distribution of ecosystem service function value is low in the central and eastern-northwestern area; the value is high in the v-shaped valleys in the southern, southeastern, and northwestern area. Most of these changes are benefited from the good policy environment and powerful means of desertification control in the study area over the years, which greatly improves the ecological environment, thus significantly increases the ecosystem service function value of the study area.(2)In 2000, 2005, and 2010, the amount of the change among the spatial patterns of the human disturbance index is relatively small According to the area, levels are ranked as: the moderate interference region, the mild interference region, the severe interference region, and no interference region. From the proportion, the intensity of human disturbance in the study area is large. Human factors and the changes of ecosystem service function have great relevance. Therefore, for the better governance of the ecological environment problems in the study area, greater effort to limit the human disturbance is needed. We should add some beneficial human intervention, and guide the ecosystem in the study area to develop in a healthy, good, and sustainable direction.(3)In the study area, the ecosystem service value in the moderate interference region was the highest in nearly a decade, followed by the mild interference region and severe interference region, and the no interference region came last. In the past ten years, the ecosystem service value proportion of the no and severe interference regions presented a rising trend; however, the proportion of the mild and moderate interference regions had a decreasing trend. From the perspective of the spatial pattern, there wasn’t any obvious change in the ecosystem service value of the interference regions.Analysis shows that the composition of the ecosystem service value in the study area and the intensity of human disturbance have great relevance, and the spatial changes in the intensity of human disturbance cause spatial differences of ecosystem service function value. In the past decade,with the help of the good policy and the countermeasures against rocky desertification, the intensity of human disturbance of the study area has continuously been weakened, making the ecosystem service function value in the study area have a steady improvement. But from the distribution of the ecosystem service value of the different intensities of human disturbance, the value of the moderate interference region is on the high side, while the value of the mild interference region is low. In future, we should strengthen the research and management measures on the moderate interference region, gradually reducing the area ratio of the moderate interference region, increasing the area ratio of the no and mild interference region.