Ecological Benefits and Plant Landscape Creation in Urban Parks: A Study of Nanhu Park, Hefei, China

Plant landscape creation in urban parks is an important aspect of urban ecological construction under the goal of "carbon neutrality". In this study, the plant community of Nanhu Park in Hefei City was considered the research subject, and its tree species' composition and diameter at breast height (DBH) were analyzed. The ecological benefits of the park's green space were evaluated using the i-tree Eco model, and the carbon sequestration, runoff retention, air pollution removal, and oxygen production benefits were quantified as economic values and combined with the landscape effect evaluation method. The results show that Nanhu Park is rich in tree species types, with 5871 trees of 41 species in 23 families and 32 native species, among which three species of Sapindus mukorossi, Eucommia ulmoides, and Triadica sebifera accounted for 43.7% of the total number of trees. The dominant tree DBH was intermediate (7.6-15.2 cm). In Nanhu Park, the economic benefits were ordered as follows: carbon sequestration > runoff retention > air pollution removal > oxygen production benefits. The dominant tree species strongly contributed to the total ecological benefit of urban park green space; the ecological benefit of individual trees was not positively correlated with the number of tree species; native tree species had better ecological and landscape effects, while plant communities with growth changes and hierarchical depth of landscape were more popular. The analysis of ecological benefits and landscape evaluation of urban park green space provide a theoretical basis for enhancing the plant landscape, thus providing a case reference for promoting the construction of park green space in Hefei.