渭河流域生态系统服务权衡优化研究

Trade-offs and optimization among ecosystem services in the Weihe River basin

研究生态系统服务之间以及与土地利用类型之间的复杂关系,进行生态系统服务导向下的土地利用优化,对实现社会经济与生态保护协调可持续发展具有重要的意义。以渭河流域关中-天水经济区段(简称关天段)为研究对象,在子流域尺度估算了2000—2013年的生物多样性、固碳和产水3种生态系统服务量,定量化研究彼此之间的权衡和协同关系;并利用CA-Markov模型预测2050年土地利用变化情景,以此测算未来情景下的生态系统服务并引入生产可能性边界(PPF)方法,进行权衡与协同分析,探究2050年最优生态系统服务下的土地利用格局。研究得出:(1)2000—2013年研究区的总产水量呈增加趋势。秦岭与六盘山地区总固碳量较大,生物多样性质量较高;而关中平原地区人口和城市分布较多,固碳能力较差,生境退化度普遍较高。(2)固碳与生物多样性之间呈现协同关系,而产水与生物多样性和产水与固碳之间均表现为权衡关系。(3)绘制了2050年的生态系统服务下的最优帕累托效率曲线,并进一步进行权衡协同分析,得到相对应的土地利用优化图。将生态系统服务及权衡需求纳入到土地决策和优化管理过程中,将有助于研究区的生态,社会和经济达到共赢状态。

With the rapid increase in human population and the excessive utilization of natural resources,humans frequently enhance the production of some services at the expense of others. Therefore,it is important to accurately understand the trade-offs and synergies among ecosystem services and explore land use optimization in order to improve ecosystem services in the Weihe River watershed. In this study,we first simulated and mapped three key ecosystem services at the sub-basin level from 2000 to 2013,including water yield,carbon sequestration,and biological diversity. Then,we quantitatively analyzed the dynamic changes in trade-offs and synergies between ecosystem services by using R language programs and production possibility frontiers（ PPF）. Finally,the CA-Markov model was used to predict land use change scenarios for2050. We estimated and optimized the qualities of various ecosystem services in 2050 and the optimal pattern of land use was generated based on the Optimal Pareto Frontier between ecosystem services. The results indicate that：（1） the water yield increased in the Weihe River watershed from 2000 to 2013. The total quantity of carbon sequestered in the Qinling Mountains and Liupan Mountains was relatively large and the biodiversity quality was relatively high. The Guanzhong Plain region had a large population and urban distribution, the carbon sequestration capacity was poor, and the habitat degradation degree was generally higher.（2）There were tradeoffs between water yield and carbon sequestration,as well aswater yield and biological diversity. There was synergy between carbon sequestration and biological diversity.（3） The optimal pattern of land use was generated based on the Optimal Pareto Frontier between ecosystem services in 2050. Our research suggested that integrating ecosystem services and trade-off analyses into land system architecture and optimal management is of great value to the sustainable development of the environment and economy.