武汉中心城区生态系统服务额外需求量化评估——缘起绿色基础设施供需错配

生态系统服务从产生到使用是一个动态流动过程,分别对应着生态系统服务的供给与需求,然而在城市化过程中,人口的聚集及绿色基础设施的破碎导致城市生态系统服务供需失衡极为严重。当生态系统服务供给无法满足需求时,则存在生态系统服务额外需求。通过量化评估生态系统服务的额外需求,将为绿色基础设施的精确供给提供决策依据。以武汉中心城区为例,以街区作为基本单元,选择合适的环境质量标准作为额外需求阈值,对以下4项生态系统服务额外需求进行量化评估与空间制图:空气净化、雨洪调节、温度调节和游憩服务,并采用熵值法求得各项服务的权重,叠加得到综合的生态系统服务额外需求。最终评估结果可作为武汉中心城区绿色基础设施优先实施区域与类型的规划依据。

Evaluation of Ecosystem Services Excess Demandin the Central Area of Wuhan: A Discussion Basedon Mismatches between Supply and Demand ofGreen Infrastructure

The ecosystem service is a dynamic flow process from itsproduction to usage, which corresponds to the supply and demandof ecosystem services. However, in the process of urbanization,the accumulation of population and the fragmentation of greeninfrastructure lead to a serious imbalance between supply anddemand of urban ecosystem services. When the supply of ecosystemservices can not meet the demand, there is an excess demand forecosystem services. A quantitative assessment of the ecosystemservices excess demand provides a decision-making basis for theprecise supply of green infrastructure. Taking the central area ofWuhan as an example, appropriate environmental quality standardswere selected as the excess demand threshold, the following fourecosystem services excess demands were quantified and spatiallymapped in a street scale: air purification, flood regulation, heatregulation, and recreation. The weights of each service wereobtained through entropy-based weight method, and then theywere superimposed to gain ecosystem services aggregated excessdemand. The final evaluation results can be used as the planningbasis for the priority implementation area and type of greeninfrastructure in the central area of Wuhan.