鳥取市の街区公園における郷土樹種と非郷土樹種の現況

抄録

In order to clarify the present state of tree species composition in block parks, the authors have recorded individual number of all the planted and seedling trees in 93 block parks in Tottori City in 2002. To compare with them, the same investigation was also done in 9 shrine woodlands and one landscape park. Consequently, in the block parks, 156 species and 7,455 individuals were recorded as planted trees. Among them, only 37.8% species and 18.2% individuals were native species. In contrast, among 84 species and 3,579 individuals of seedling trees, 57.1% species and 69.9% individuals were native species. In the shrine woodlands, 63.5% species and 76.2% individuals were native species. In the block parks, 77 individuals of seedling trees grew exceed height of 2m and 24.4% of them were Robinia psedoacacia (alien species) and 14.3% were Cinnamomum camphora (domestically alien species) . In the block parks, alien trees were dominant; moreover, well-grown seedling trees were also non-native species. This state is problem for both conservation of local landscape and biodiversity. The authors suggested that native trees are recommended for planting rather than non-native trees in block parks.