The evolutional analysis of coupling relationship between population and resource-environment in Gansu Province, China

Gansu province lies in the northwest of China and its eco-environment system is fragile. Due to the rapid growth of population and the remarkable expansion of the economy since the implementation of the economic reforms in 1978, the demands for resources have been increasingly expanding and the eco-environment has been greatly influenced in Gansu. As a result, the human-land contradiction in the region is becoming increasingly conspicuous. Based on panel and serial statistical data, the coupling relationship between population and resource- environment in Gansu province is evaluated through the use of improved analytical hierarchy process and the coordinated development degree (CDD) model for the years from 1990 to 2004. We found several trends. Firstly, the integrated population development capability increased linearly through the whole study periods. The maximum value for the integrated population development index (IPDI) was reached in 2004 (0.875). Secondly, the integrated resource-environment status has generally declined with some annual fluctuations since 1990, while the integrated resource-environment utilization index (IRUI) has decreased from 0.601 to 0.39. Thirdly, the coupling relationship between population and resource-environment varied gradually from minor maladjustment to moderate harmony, and then recently shifted to secondary harmony. The maximum value of CDD (0.753) was reached in 1999. The direct cause of the quantitative variations of coupling relationship is that population system and resource-environment system didn´t continuously track each other from 1990 to 2004. Finally, the carrying capacity of the environment is limited, while the demands of human beings are increasing, so programs for sustainable development face huge pressure in Gansu. Given this situation, it is difficult to achieve the goal of an all-round well-off society since per capita GDP in Gansu was only 3,668 yuan in 1999.