Patterns and drivers of plant biodiversity in Chinese university campuses

Urban biodiversity is strongly correlated with human well-being and is quickly becoming a new research field. Most previous studies in this field focus on patterns of species richness but few consider species and trait compositions and how these are shaped by anthropogenic and environmental drivers. Such information, however, is critical for effective planning and management of urban species. We compiled published species lists from 71 Chinese university campuses. We also collected environmental data for each campus, including anthropogenic (campus age and area) and environmental variables (climate and topography), to explore the distribution patterns and the drivers of species richness, composition and traits. We found that university campuses in China maintain substantial plant diversity, including at least 1565 woody and 1614 herbaceous species. The distribution pattern of campus species richness was mostly driven by anthropogenic variables, being positively correlated with campus age and size. In contrast, campus species composition and leaf traits were mostly driven by climate variables. This was especially true for woody plants of which campus species composition and traits were more constrained by mean annual temperature than herb species. Our study provides a basic but diverse database for the selection of campus plants, which can benefit the management of urban ecosystems. Our results reveal that landscape design can influence urban species richness, species composition is still restricted by the natural environment. Hence, many endangered species can be protected in these human-friendly urban ecosystems if they have suitable traits adapted to local climatic conditions.