Evaluation of main regulating, provisioning, and supporting ecosystem services of urban street trees: A literature review

In urban ecosystems, the value of green spaces and biodiversity is increasingly recognized, and street trees provide beneficial effects or ecosystem services. However, street trees are not all the same, and some species are better suited for specific urban contexts and provide more benefits than others. Considering an extensive literature, here we provide a framework to evaluate the various ecosystem services that street tree species can provide in urban environments related to regulating, provisioning, and supporting services. For each ecosystem service, we selected the numerous morphological, physiological, and ecological features of the tree species that can affect the provision and extent of the benefits. An ideal species does not exist because some traits can be beneficial in certain climates or for specific functions and be negative for others. Here, we suggest an array of traits that urban planners can look for if they want to maximize a specific ecosystem service rather than another. For instance, evergreen, tall, fast-growing species are potentially the best types of trees if urban planners want to maximize carbon sequestration amounts, but the same traits could be negative for other ecosystem services. All in all, we recognize that maintaining a diversity of tree species, with an array of morphological, physiological, and ecological features, can diversify and possibly increase the provision of ecosystem services.