深圳次生林群落结构与植物多样性

Community structure and plant diversity of secondary forests in Shenzhen

为了重建近自然的乡土植被景观,近些年深圳市大力推进退化人工林的美景诱导与近自然化绿化工程。笔者对深圳市保存较好的天然次生林进行了调查研究,结果表明:深圳现有次生林分为厚壳桂+假苹婆+铁榄林、鸭脚木+豺皮樟+黧蒴林、杉木+银柴+九节林和阴香+南洋楹+糖胶树林4种基本类型;与邻近香港、广州白云山相比植物组成有很大相似性;现有次生林的乔木层高度多在10m以下,中小径级树木占明显优势;不同类型群落多度格局都遵循对数级数分布,不同类型次生林的物种多样性指数差异不太明显,处于演替中期的鸭脚木+豺皮樟+黧蒴林物种多样性最高,针阔混交的杉木+银柴+九节林灌木层物种多样性最高。

In order to rebuild the natural landscape with the native vegetation, this paper aimed to offer a model and a theoretical basis for the recent eco-landscaping forest construction from natural secondary forest in Shenzhen area . Based on field investigation, We set up 15 fixed plots whose area is 30 m × 40 m in Xiaomeisha, Yantian district, Paiya Mt. , Longgang district and Yangtai Mt. , Baoan district. The factors investigated include diameter at breast height of trees （ DBH ≥ 1.0 cm） , tree＇s height, coverage and the number of shrubs and herbaceous with the method of grid sampled. All data are dealt with SPSS11.0. cluster analysis show that the current secondary forest in Shenzhen can be divided into 4 forms, i.e. , Cryptocarya chinensis ＋ Sterculia laneeolata ＋ Sinosideroxylon wightianum community, Schefflera octophylla ＋ Litsea rotundifolia ＋ Castanopsis fissa community, Cunainghamia lanceolata ＋ Aporosa dioica ＋ Psychotria rubra community, Cinnamomum burmannii ＋ Albizia falcataria ＋ Alstonia scholaris community. Comparing with research made in the Baiyun Mt. , Guangzhou and in Hong Kong, the species and the structure of secondary forest community are rather similar. It is also found that the percentage of trees with smaller diameter and the tree＇s height below 10 m is much more in the existing secondary forest. All communities follow log-series distribution model. The biodiversity index of four kinds secondary forest vary insignificantly, in which the S. octophylla ＋ L. rotundifolia ＋ C.fissa community has the highest species diversity, the mixed conifer C. burmannii ＋ A.falcataria ＋ A. scholaris community has the highest shrub species diversity.