Coupling of ecological health and ecological carrying capacity in the Gannan pastoral area based on the 3S technology

Abstract： Ecological carrying capacity is one of the main features of overall level of ecosystem, and its quantification has become a decisionmaking requirement for ecological environment management and regionally sustainable development. The index system was established by using satellite imagery (TM, ETM+) and census data to evaluate the ecological carrying capacity with ecosystem health in the Gannan region. The main indicators were calculated by 3S (GIS, RS, GPS) technology which were used to analyze Spatial data and the AGAAHP was used to calculate the weight value of each index, and then these data were applied to determine the ecological carrying capacity of each county in the Gannan region with the help of State Space Method. This study indicated that the reduction of ecological carrying capacity resulted from the decline in environmental bearing capacity and ecological elastic force, as well as the increase in human social influence during 2000-2008. In the past decade, the environmental bearing capacity kept unhealthy status, and ecological elastic force decreased from subhealth status to sick status. The human social influence changed into unhealthy status. The comprehensive analysis showed that the ecological carrying capacity kept the subhealth status in the past decade.