Location matters. A systematic review of spatial contextual factors mediating ecosystem services of urban trees

To ensure and maintain ecosystem service delivery in cities undergoing densification, strategic tree planting is important. The effects of tree location on ecosystem service delivery have been emphasised. However, there is no integrated overview of the different aspects of tree location, here called spatial contextual factors, that mediate urban tree ecosystem services. This paper presents the results of a systematic literature review and provides a comprehensive overview of spatial contextual factors recognised by research as relevant for ecosystem service delivery by urban trees. To support creating such an overview, we first gain insight into the current common understanding of what spatial context is conceptually and how it participates in the co-production of ecosystem services. We find that generally, spatial context is represented by both social and ecological structures and processes and that it mediates ecosystem services by four mechanisms along the ecosystem service cascade. In the next step, we identify 114 unique spatial contextual factors mediating 31 ecosystem services of urban trees. Of all factors, people, represented by physical location, socio-demographics or building functions, mediate the highest number of services, highlighting the importance of urban planning and design in mediating urban tree ecosystem services.