Urban trees in university campus: structure, function, and ecological values

University campuses usually have more trees and can provide various ecosystem services. However, there are few reports on tree ecosystem services of Chinese university campuses, especially in northern China. This study investigated the trees in the campus of Shenyang Institute of Technology and analyzed its ecological benefits and monetary value through i-Tree Streets. The campus trees contained a total of 5193 trees of 66 species, of which Catalpa ovata G. Don, Acer mono Maxim., Rhus typhina Nutt, and Salix babylonica L. accounted for 59.7% of the total number. The age structure of the trees in the campus was not ideal, with 71.5% of young trees, 24.0% of maturing trees, 4.5% of mature trees, and only 0.04% of old trees. The trees in the campus provided more energy saving benefits ($60,850, $11.7/tree), carbon reduction benefits ($34,318, $6.6/tree) and aesthetic benefits ($30,150, $5.8/tree). The benefits resulted from air pollutant removal ($12,889, $2.5/tree) and rainwater runoff interception ($15,534, $3.0/tree) were smaller. In addition, tree species with more maturing trees and mature trees (i.e., with larger diameter at breast height) and large leaf area in the campus contributed significantly to ecosystem services. Our results can provide suggestions and certain insights for Chinese campus greening managers in tree species selection and tree management.