PLANTING DESIGN AND VEGETATION MANAGEMENT FOR PROMOTING BIODIVERSITY AT A UNIVERSITY CAMPUS - EXAMPLE OF BUTTERFLY

Conservation of biodiversity is an important global challenge to ensuring future sustainability. University campuses can provide valuable resources for biodiversity; however, this is not yet fully recognized and sufficiently researched. The present study was carried out to show the biodiversity value of different green spaces at the Chiba University Nishi-Chiba Campus. Butterflies were chosen as indicators at ten sites: one intensive green roof, four meadows, two roads, two open spaces and one kitchen garden. From June 2010 to November 2010, butterfly surveys were carried out by transect counts from 8:00 am to 12:00 pm every two weeks, ten times in total. We identified 705 individuals of 25 species from 5 families. The species were mainly those common to urban areas near Tokyo. The results showed that the highest number of butterfly species and the highest total number of butterflies were observed in the kitchen garden, where various medicinal herbs provided a continuous source of nectar. On the contrary, the lowest total number of butterflies was found on the intensive green roof, although the Shannon-Weaver diversity index (H’) value was high. The meadows provided a valuable habitat for the butterflies, and the roads connecting the campus green spaces were an important passageway for the butterflies. In the open spaces, areas planted with flowerbeds attracted a high number of butterflies. In conclusion, the university campus provided favorable habitats for butterflies; however, careful planting design and management is required to maintain nectar sources and host plants to maximize the biodiversity benefits of each green space.