Ecosystem Health Assessment of Gan River Upstream based on PSR Model

According to the characteristics of the ecosystem Gan River upstream basin using the 'pressure-state-response'(PSR)frame model,the ecosystem health evaluation index system and evaluation model of Gan River upstream were established,with which the ecosystem health in Gan River upstream basin in 2005 was evaluated.The results showed that: the overall situation of ecosystem health in Gan River upstream basin is good which belongs to the second level of health.Of 16 counties,Zhanggong area of Ganzhou belongs to the fifth level which is relatively poor,Chongyi,Anyuan,Shicheng etc 11 counties belong the second level of health,accounting for the majority of proportion,Xingguo,Ganxian,Yudu,Nankang counties belong to the third level of health.In addition,in accordance with the main factors which restrict ecosystem health of each county,some countermeasures to improve health level are put forward.