徐州耕地生态经济系统结构、功能及可持续性能评价

研究目的:评价1990—2006年徐州耕地生态经济系统运行及可持续性能状况。研究方法:能值理论和方法。研究结果:(1)提出基于能值的"粮经比",衡量农村产业结构调整程度,徐州耕地生态经济系统基于能值的"粮经比"已由72∶28调整为48∶52;(2)不断增长的工业辅助能投入(电力、燃料、机械、农药、化肥)未能提高系统的净能值产出率,却在持续增加系统的环境负载率;(3)随着产业结构调整,系统内粮食作物和经济作物的能值产出结构趋于平衡、合理,系统的自稳定性逐渐增强;(4)系统的可持续性能很弱,且呈下降趋势。研究结论:基于能值的徐州耕地生态经济系统产出率和可持续性能不高,应实现由"石油农业"向生态农业的转变。

Structure, Function and Sustainability Assessment of Eco-economic System of Cultivated Land in Xuzhou

The purpose of this paper is to assess the operation and sustainability of eco-economic system of cultivated land in Xuzhou from 1990 to 2006. Methods of energy theory and analysis were employed. The results indicate that: （1）the proportion index of grain crops to economic crops based on energy theory was put forward in order to measure the degree of rural industrial structure adjustment. The index of Xuzhou has been adjusted from 72:28 to 48:52;（2）the increasing industrial auxiliary input (e.g., electric power, fuel, machinery, pesticide, chemical fertilizer) did not improve the output ratio of net energy in the system, on the contrary, the environmental cost of the system had been increased continuously;（3）during the industrial structure adjustment, the energy output structure of grain corps and economic corps in the system tended to be balanced and reasonable, and the self stabilization of the system was enhanced gradually;（4）sustainability of the system was very weak and the index was with downward trend. It is concluded that the output ratio and sustainability of eco-economic system of cultivated land in Xuzhou based on energy theory were not high. The development mode should be changed from the so-called petro agriculture into ecological agriculture.