1.School of Ecology and Nature Conservation, Beijing Forestry University;2.Department of Biology and Information Engineering, Yiyang Vocational & Technical College;3.Research Institute of Forestry, Chinese Academy of Forestry
Ecosystem vulnerability is a core issue of global climate change and sustainable development research. Measuring and evaluating of vulnerability are essential for understanding the structure and function of ecosystems. Tianshan-Tarim Oasis contains multiple types of ecosystems such as mountain, desert and oasis, and there are many ecotones between different ecological types. Gross primary productivity (GPP) of vegetation, which is the total amount of carbon uptake by vegetation photosynthesis, is an important functional indicator of terrestrial ecosystem. GPP is not only an important index to measure the health status of ecosystem, but also a result of comprehensive effects of the environmental limiting factors on ecosystem. The fluctuation of vegetation productivity can also be used as an indicator to measure the vulnerability of ecosystem. In this study, GPP products with a spatial resolution of 1 km retrieved from Moderate-resolution Imaging Spectroradiometer (MODIS) were chosen to calculate and evaluate the ecosystem vulnerability of the study area. Based on vegetation productivity, the vulnerability of the study area is calculated and classified into not vulnerable, mild vulnerable, moderate vulnerable, severe vulnerable, and extreme vulnerable. The spatial distribution characteristics of ecosystem vulnerability and its relationship with environmental factors were also analyzed and discussed. The results showed that: (1) the ecosystem vulnerability of the study area presented an obvious spatial differentiation pattern on the whole, with moderate and severe vulnerability as the main feature, and the extremely vulnerable areas were mainly distributed in the southern Tarim Oasis; (2) the vulnerability of the ecosystem generally increased with the rise of the mean annual temperature in the region. Affected by surface water irrigation, there was no obvious trend between ecosystem vulnerability and precipitation; (3) the vulnerability of the ecosystem in the study area indicated a downward trend with the increase of the average altitude and the average slope in the area. Due to harshly natural conditions, overgrazing and over-exploitation of farmland, the area currently showed a state of serious vulnerability. Therefore, the ecological governance should be actively carried out, the key areas of ecological functions should be rationally planned, grassland, wetland and other easy-to-reclaim areas should be protected, the red line of the scope of oasis development should be delineated, farmland reclamation should be restricted, and the distribution of water resources in the Tarim River Basin should be coordinated. This study provides a methodological reference for using satellite remote sensing data to study the vulnerability of ecosystems, and provides a scientific evidence for sustainable development and ecological governance.
王鹤松,何敏,闫薇,艾金龙,褚建民.基于遥感GPP的天山-塔里木绿洲地区生态系统脆弱性研究.生态学报,,(). http://dx. doi. org/10.5846/stxb202101130132复制