Imbalanced supply and demand of temperature regulation service provided by urban forests: A case study in Shenzhen, China

Urban forests can provide temperature regulation service (TRS) by lowering the local temperature and further mitigating the urban heat island effect. Numerous studies have focused on how to better realize or enhance the cooling function of urban forests, but have not considered that from the perspective of supply and demand. Here, we develop a framework to quantify the supply and demand of temperature regulation service provided by urban forests, using remote sensing, meteorological and socio-economic data. Taking Shenzhen city as a case study, we analyzed the spatial distribution of both TRS supply and demand as well as their relationship in Shenzhen. We found: 1) TRS supply varied greatly in space, with areas of high supply generally located in the southeast of Shenzhen, which is mainly covered by forests, and around the boundaries of administrative districts that are distant from the urban centers. 2) TRS demand had even more significant spatial heterogeneity, showing that high-demand areas were primarily distributed in the southwest but occupied a relatively small amount of land in Shenzhen. We then categorized the spatial relationship between TRS supply and demand into four types, and identified the hotspots of highly mismatched supply and demand of TRS. Targeted urban forests planning and management measures were further proposed for each type of region. This study provides spatial tools and insights for urban forests design and planning towards better urban heat mitigation and adaptation.