梅州市城区行道树的结构特征

Structure Characteristics of Street Trees in Meizhou City

采用抽样调查方法对梅州市城区20条主要道路的行道树进行调查,分析梅州城区行道树的组成特征、结构特征,探讨多样性指数和物种重要值。结果表明:1)梅州城区行道树共有13科18属23种7133株,其平均胸径、平均冠幅、平均树高分别为27.59cm,4.10m,6.94m,总体上看,平均冠幅偏小;2)物种丰富度指数S、Shannon-Wiener指数H和Simpson指数D偏小且各道路间差异明显,说明各道路行道树存在一定程度的物种单一性、层次的单调性;3)梅州市城区行道树优势树种是大叶榕、垂榕、大王椰子,次优势种为海南榄仁、阿珍榄仁、阴香,它们是梅州城市街道绿化的好树种。基于南亚热带植物区系的特点,提出了梅州城区行道树的骨干树种、一般树种、试用树种名单,共计50种。

Based on an investigation of the street trees of 20 main streets in the urban area of Meizhou city, the composition, structure and characteristics as well as species diversity, importance value of the street trees were analyzed. The results were as follows： 1） There were 7 133 trees, belonging to 23 species and 18 genera and 13 families, and their average DBH, crown and height were respectively 27.59 cm, 4.10 m and 6.94 m. In general their average crown was relative small. 2） S （abundance index）, H（ Shannon-Wiener index）, and D （Simpson index） of biodiversity index were small, and there were the obvious difference in those indexes among different streets, which suggested that there were certain monotone of the tree species and structure layer. 3） The dominant species mainly consisted of evergreen trees that were Ficus virens var. sublanveolata, Ficus benjamina, Roystonea regia, Terminalia hainanensis, T. arjuna, Cinnamomum burmannii, and they were excellent tree species to fit for streets of Meizhou city. In the end, a list of 50 species, including major, general and tentative trees, were proposed according to characteristics of flora in the south subtropics.