摘要
为了研究生态恢复过程中复合承载力变化,以陕北县南沟小流域的生态恢复试验为例,应用能值方法揭示了该流域的动态可持续性.同时,应用情景模拟方法研究了在不同能值生活标准下的承载力变化,探讨了生态恢复对承载力的影响.结果显示,2002～2005年流域环境负载率(ELR)总体上有所下降,持续性指数(ESI)有所增加.流域可更新资源承载力、中国1996年生活标准下以及全球1999年生活标准下的人口承载力分别为938人(下限)、10853人和3020人(上限).根据基于面积的承载力计算方法,流域可更新资源承载力和中国1996年生活标准下承载力分别为17844hm2和6572hm2,分别为流域面积的3倍和1.1倍.上述结果表明,生态恢复提高了流域资源利用和转换效率,环境负载率下降,流域现有人口及其生产规模基本在其承载力范围内,但已经接近上限.鉴于当前较低的生活标准,流域的承载力有待进一步提高.
Ecological-economic carrying capacity is a complicated issue which must be addressed. To explore the evolution of ecological-economic carrying capacity in the process of ecological restoration, the Xiannangou small catchment in Northern Shaanxi province was used as a case study site. Sustainability dynamics for this catchment were clarified by employing emergy accounting and the catchment carrying capacity was simulated for different living standards in emergy terms using scenario analysis to quantify the impacts of ecological rehabilitation on the carrying capacity. The results showed that ：① over the period 2002 - 2005, environmental loading ratio （ELR） decreased and the emergy-based sustainability index （ESI） generally increased.②The people-based carrying capacity for renewable resources was 938 persons （lower limit）, that for the Chinese living standard in 1996 was 10853 persons and for the global living standard in 1999 was 3020 persons （upper limit）. ③ The area-based carrying capacity for renewable resources and the one on the Chinese living standard in 1996 were 17844 hm^2 and 6572 hm^2 , about 3 and 1.1 times the area of the catchment, respectively. The results above suggest that ecological rehabilitation contributed to the improvement of resource use and conversion efficiency, as well as to decreases in the environmental loading ratio at the catchment level. The population size and production scale ranged within the interval between the lower and upper limits for carrying capacity. Given the present lower living standard, the ecological-economic carrying capacity has to be enhanced at the catchment scale.
出处
《环境科学学报》
CAS
CSCD
北大核心
2009年第12期2658-2665,共8页
Acta Scientiae Circumstantiae
基金
中科院科学院西部行动计划(No.KZCX2-XB2-05)
国家科技支撑计划项目(No.2006BAD09B10-2)
国家自然科学基金(No.4077108)~~
关键词
生态经济承载力
生态恢复
能值生活标准
carrying capacity
ecological rehabilitation
living standard in emergy terms
