洱海流域生态-农业系统动态耦合过程分析

Dynamic Coupling in an Eco-agricultural System in a Highland Lake Basin:A Case Study of Erhai Lake

以农业面源污染为研究重点,探究兼顾生态与发展职能的流域生态-农业系统的耦合过程与机制,为高原湖泊流域污染治理和生态农业发展提供依据。选择洱海流域为研究对象,运用系统耦合理论,构建系统综合评价模型、系统耦合度测度模型、系统耦合协调模型和系统耦合演化模型,对1994-2015年洱海流域系统耦合度及动态耦合过程进行分析。1994-2015年,洱海流域生态-农业综合发展指数和耦合度均呈上升趋势,经济-生态系统总体向良好状态发展,经济发展对流域生态环境质量的威胁不断弱化,两者协调发展水平维持磨合、提升。1994-2015年洱海流域生态-农业系统耦合协调度为0.46-0.88,经济发展子系统与生态环境子系统总体呈现协调耦合的状态,其中1994-2002年处于拮抗时期,2003-2005年仍然处于拮抗时期但耦合度下降趋势得到扭转,2006-2011年进入磨合阶段,2012-2015年进入高水平耦合阶段但保持与促进难度较大。耦合态势可分为磨合消耗阶段（1994-1998年）、快速消耗阶段（1999-2003年）、快速协调阶段（2004-2007年）和磨合协调阶段（2008-2015年）,揭示了生态农业政策的短期效益,预示流域农业面源污染治理的困境。系统耦合测度有效识别了洱海流域生态-农业系统演化阶段与特征,农业生产方式制约着洱海流域生态-农业系统协调耦合,磨合协调阶段下农业面源污染治理需要持续推进。

Research on integrated ecological-agricultural-social systems is one of the frontiers of ecological economics and this coupling is vital for sustainable development. To provide a basis for pollution control and eco-agricultural development of plateau lake basins,we selected Erhai Lake for a case study,exploring the coupling process and its mechanism by focusing on agricultural non-point source pollution. Based on system coupling theory,we developed four related models; a comprehensive evaluation model,a system coupling measurement model,a system coupling coordination model and system coupling evolution model. Then,using the models,the dynamic coupling processes of an eco-agriculture system in the Erhai Lake basin from 1994 to 2015 were analyzed. Data was obtained from the statistical yearbook and monitoring data collected by the local environmental protection agency. The comprehensive ecological-agricultural development index and coupling degree in the basin both increased during the study period. The economic-ecological system continued developing and the coupling of economic development with environment quality increased steadily. From 1994 to 2015,the coupling degree of the eco-agriculture system in Erhai Lake basin increased from 0. 46 to 0. 88,and the relationship moved through several phases： an antagonistic period（ 1994-2002）,an antagonistic period with reversed coupling（ 2003-2005）,coupling（ 2006-2011）,high level coupling with difficulties in maintenance and promotion（ 2012-2015）. The coupling was divided into running-in consumption stage（ 1994-1998）,rapid consumption stage（ 1999-2003）,fast coordination stage（ 2004-2007） and running-in coordination stage（ 2008-2015）. This series of stages revealed the short-term benefits of the eco-agriculture policies and predicted the results of agricultural non-point source pollution control.The coupling measurement system effectively identified the stages and characteristics of the ecological-agricultural system in the Erhai Lake basin,where the existing agricultural production mode limited harmonious coupling of the ecological-agricultural system. The integrated system is providing important benefits,but control of agricultural nonpoint source pollution should be promoted during the running-in coordination stage.