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 Demand in the Central Area of Wuhan: A Discussion Based on Mismatches between Supply and Demand of Green Infrastructure

The ecosystem service is a dynamic flow process from its production to usage, which corresponds to the supply and demand of ecosystem services. However, in the process of urbanization, the accumulation of population and the fragmentation of green infrastructure lead to a serious imbalance between supply and demand of urban ecosystem services. When the supply of ecosystem services can not meet the demand, there is an excess demand for ecosystem services. A quantitative assessment of the ecosystem services excess demand provides a decision-making basis for the precise supply of green infrastructure. Taking the central area of Wuhan as an example, appropriate environmental quality standards were selected as the excess demand threshold, the following four ecosystem services excess demands were quantified and spatially mapped in a street scale: air purification, flood regulation, heat regulation, and recreation. The weights of each service were obtained through entropy-based weight method, and then they were superimposed to gain ecosystem services aggregated excess demand. The final evaluation results can be used as the planning basis for the priority implementation area and type of green infrastructure in the central area of Wuhan.