The effects of habitat network construction and urban block unit structure on biodiversity in semiarid green spaces

The promotion of urban biodiversity mainly relies on all kinds of urban green land, especially the green land affiliated with fragmentation and smaller dimensions that receives less attention. Based on small-scale connected urban green spaces, the construction of habitat networks is very important for biodiversity protection. Considering the importance of the habitat networks constructed by the affiliated green land with smaller dimensions to biodiversity protection, this research attempted to apply a new technique to construct a habitat network and an urban block unit structure for ecological restoration and green space biodiversity at the city-block scale. By analyzing the related ecological principles, this research extracted four design approaches: the green land habitat patch-companion method; the corresponding shape and function method; the newly increased and protective patch location method; the bunching patch substitution method; and the approaches for designing campus habitat galleries, such as the 3D greening method of narrow and long campus galleries, the method of designing a campus main road green belt, the method of designing a relaxed campus landscape green belt, the method of designing a core campus landscape green belt, the method of connecting the habitat patch node, and the method of covering habitat diversity. By comparing the network pattern indexes, determining the key habitat patches, constructing the habitat network frameworks, and improving the habitat aggregation quality, this research constructed three ideal network models for urban university campus habitats and explained the butterfly biodiversity model graphic representation, application conditions, and features. The "crosswise radiation" network was effective for ecological restoration, and the "dendritic zoning" network significantly enhanced butterfly biodiversity.