基于相图法的新疆精河县大农业系统可持续性能值评价

为促进干旱区大农业系统的可持续发展,以新疆精河县为研究区,从能值角度出发,利用相图法分析了1990年、1999年和2007年研究区大农业系统的能值投入情况,评价了系统能值利用的可持续性。结果表明:精河县大农业系统的能值投入中可更新环境资源能值和经济社会反馈能值比例下降,从1990年的67%下降到1999年的61%再到2007年的48%;同时不可更新环境资源能值比例上升,三年比例依次为14%,24%和38%。虽然在所研究时段内系统的能值利用是可持续的,但其可持续性指标由1990年的Ⅱ级可持续性降到1999年和2007年的Ⅲ级可持续性,且2007年的可持续性指标下降到三年中的最低。因此,系统应当从当前的发展状况出发,沿可更新资源的敏感线上行发展,主要采取节约和保护不可更新资源和可更新资源有效替代的方法,直接或间接地降低对不可更新资源的利用比率,提高系统未来的可持续发展能力。

Evaluation on the Sustainability of General Agricultural System in Jinghe County of Xinjiang Based on Ternary Diagram

For the sustainability of general agricultural system in arid area,Jinghe County of Xinjiang was chosen as a typical study area.This paper analyzed the input of its general agriculture system from the emergy point of view based on ternary diagram.Then the sustainability of system was evaluated.The results are as following: the emergy percentages of renewable resources and feedback from economic society are decreasing from 67% to 61% then to 48%,but increasing of un-renewable ones are 14%,24% and 38% in the 3-year study.At the same time,the index which can be used to indicate the sustainability of the system is descendent from the second sustainable area of 1990 to the third of 1999 and 2007 and the lowest index is in 2007 though it is sustainable.So lots of measures such as saving,protecting un-renewable resources and replacing it with renewable ones must be taken for the sustainable development of general agricultural system in Jinghe County.