采煤沉陷区复垦前后农业生态系统能值变化特征分析

采用能值理论分析方法,比较采煤沉陷区复垦前后农业生态系统能值投入和输出,结果显示,复垦后的能值总投入是复垦前的2.7倍,能值总输出是复垦前的3.1倍,能值投入率是复垦前的7.4倍,说明复垦后的农、业生态系统经济发展水平有所提高;人均能值用量是复垦前的2.7倍,表明复垦后人民的生活水平得到改善;由于复垦后农业产业结构的多元化,各产业结构正处于发展中阶段,因此,净能值产出率由复垦前的0.28降低到复垦后的0.14,但环境负荷率由复垦前的0.5上升到复垦后的3.7,系统稳定性指数由复垦前的0.10上升到复垦后的0.36,从而说明,复垦后的农业生态系统相对复垦前循环利用率和持续发展程度较高。

Effects of reclamation of coal mining subsidence on emergy characteristics of agricultural ecosystem

Emergy theory and analysis method were employed to compare the effects of pre-and post-reclamation of coal mining subsidence on emergy inputs and outputs of agricultural-ecosystem.The results showed that after reclamation,the total emergy input and output were 2.7 times and 3.1 times of those before reclamation,respectively.Reclamation significantly increased the rate of emergy input(defined asrenewable organic energy+unrenewable source production]/renewable environmental resource+nonrenewable environment...