关键词: 植物功能性状, 城乡梯度, 生存策略, 叶, 细根, 园林树木

Abstract: Functional traits are important characteristics that link plants, environment and ecosystems, with a far-reaching significance for indicating environmental changes. In this study, we measured 14 morphological, physiological, and nutrient traits of leaf and fine-root in five garden evergreen tree species, Photinia ×fraseri, Euonymus japonicas ‘Aurea marginatus’, Cinnamomum camphora, Ligustrum lucidum, and Osmanthus fragrans. The differential variations of traits across an urban-rural environmental gradient and the correlation between leaf traits and root traits were analyzed to reveal the survival and adaptation strategies of these species. The results showed that morphological traits of different tree species differed greatly. There were no significant differences in the leaf morphological traits along the urban-rural gradient. The physiological traits showed an increasing trend along the urbanrural gradient, and the similar trend was observed for carbon contents in fine roots and leaves. According to the results of principal component analysis and the theory of plant economic spectrum, the fine roots of the garden tree species tended to adopt a “conservative” strategy, and the survival strategy of tree species as whole appeared “slow investment return” type in the rural sites. This survival strategy was not found in the urban sites. Our findings indicate that urbanization may strengthen the resource acquisition ability of plants for growth and production.

Key words: plant functional trait, urban-rural gradient, survival strategy, leaf, fine root, garden tree.