四川省农业生态系统能值评价及动态计量分析

农业生态系统是人类生存的最基本系统，对其结构和功能进行分析是破解农业生态环境问题的关键.本文应用能值分析理论并借助数据包络分析法、协整检验、误差修正模型等经济计量方法，对1997-2009年四川省及其21个地级市农业生态系统的运行动态、环境承载情况、运行效率、投入产出关系进行定量分析.结果表明： 研究期间，四川省处在由传统农业向现代农业过渡阶段，农业机械化水平不断提高，资源利用效率不断加强，结构优势度总体情况较好，而过度依赖经济能值的投入使系统可持续性能力逐年减弱；区域间农业生态系统发展状况的差异较大，成都平原区和川西高原区要么资源开发过度，要么资源利用不足，而四川丘陵地区农业生态系统富有活力和发展潜力，属于四川农业未来发展的重点区域；四川省农业生态系统总体运行效率较低，各地状况不一，既包括技术效率较低因素，也有规模不当的原因；四川省农业生态系统经济能值指标与产出能值之间存在长期均衡动态关系，但短期内的能值投入远未达到理想的产出状态.

Emergy evaluation and dynamic measurement analysis of agro-ecosystems in Sichuan Province of Southwest China

Agro-ecosystem is the most basic system for human beings survival, while the analysis of the structure and function of the system is the key to solve the problems of agro-ecological environment. In this paper, emergy theory and related economic measurement methods including data envelopment analysis, cointegration test, and error correction model were applied to quantitatively analyze the operation dynamics, environmental loading, operation efficiency, and input-output relation of the agro-ecosystems in Sichuan Province and its 21 cities in 1997-2009. In the study period, Sichuan Province was in the transition period from traditional agriculture to modern agriculture. The agricultural mechanization level of the Province improved constantly, resources utilization efficiency enhanced continually, overall structural dominant degree was better, but the over-reliance on economic emergy input caused the sustainability of the system weakened gradually. The development status of the agro-ecosystems in the Province varied among regions. Chengdu Plain and Western Sichuan Highland were either in overexploited or in underutilized, while the hilly areas were full of vitality and development potential, tended to be the important areas for the future development of Sichuan agriculture. Generally, the operation efficiency of the agro-ecosystems in the Province was relatively low, with the situation differed in different regions due to the lower technical efficiency or improper scale. There was a long-term equilibrium between the economic emergy indices and output emergy, but the short-term emergy input didn't reach the ideal output.