九连山常绿阔叶林群落的结构与种类数量特征

在线路调查和样方调查的基础上，分析了江西省九连山国家级自然保护区常绿阔叶林典型群落的结构与数量特征。群落主要由热带、亚热带科属组成，优势科为壳斗科Fagaceae，樟科Lauraceae，山茶科Camelliaceae，安息香科Styracaceae，杜鹃花科Ericaceae和木兰科Magnoliaceae等科，优势树种以相应的优势科属树种为主。物种数量特征采用重要值进行分析。结果表明，75个样地中，胸径≥3cm的个体密度1808株·hm^-2群落相对较高大，平均高度达11．5m，乔木垂直分化较明显：林木平均径阶为14．2cm，树种水平分布不均。许多常绿阔叶林群落正处于过老与更新发展之中，并常见有阳性落叶树种如枫香Liquidambar formosana，拟赤杨Alriphyllum fortunei和光皮桦Betula lurainirera等侵入林窗，形成常绿阔叶树与落叶阔叶树混交林。

Species number and structural characteristics of the subtropical, evergreen broad-leaved forest on Mount Jiulianshan, Jiangxi, China

For the evergreen broad-leaved forest in National Nature Reserve of Mount Jiulianshan, Jiangxi Province, plot sampling （75 plots of 10 m×10 m） and importance value were used to quantify species and describe their structural characteristics. Results of sampling showed that the typical evergreen broad-leaved forest of Mt. Jiulianshan consisted mainly of subtropical families and genera with dominant families including Fagaceae, Lauraceae, Camelliaceae, Styracaceae, Ericaceae, and Magnoliaceae. Tree density for diameter at breast height （DBH）≥3 cm was 1 808 individuals per hectare with an average height of 11.5 m. Vertical tree stratification was apparent, and horizontal distribution was uneven with an average DBH of 14.2 cm. Vegetation on Mt, Jiulianshan consisted of a combination of natural forest, secondary natural forest, and silvicultural regeneration. Some evergreen broad-leaved communities were over-mature or being regenerated. In addition, various hardwood trees were found, such as Liquidambarformosana, Alniphyllum fortunei, and Betula luminifera, which invaded canopy gaps forming mixed evergreen and hardwood broad-leaved forests.