云南哀牢山中山湿性常绿阔叶林20 hm2动态样地的物种组成与群落结构 / Species composition and community structure of a 20 hm2 plot of mid-mountain moist evergreen broad-leaved forest on the Mts. Ailaoshan, Yunnan Province, China
中山湿性常绿阔叶林是分布在我国亚热带气候区的一种山地森林植被。为监测此类森林的动态过程, 按照Centre for Tropical Forest Science的建设标准, 于2014年在云南省景东县徐家坝附近的中山湿性常绿阔叶林中建立了一块20 hm 2的森林动态样地, 测量并记录了样地中所有胸径(DBH) ≥ 1 cm的树木直径及其分枝的直径, 并对其挂牌标记、定位和鉴定, 分析了其物种组成和群落结构。结果显示: 样地内共有DBH ≥ 1 cm的木本植物独立个体44 168株, 隶属于36科63属104种。重要值最大的前3个科依次是壳斗科、茶科和樟科。在属的水平上, 热带区系成分占总属数的46.0%, 温带区系成分占38.1%。重要值≥1的物种有22个, 占总个体数的84.6%。重要值最大的3个种依次是蒙自连蕊茶(Camellia forrestii)、云南越桔(Vaccinium duclouxii)和多花山矾(Symplocos ramosissima)。胸高断面积之和排名前4名的物种为硬斗柯(Lithocarpus hancei)、木果柯(L. xylocarpus)、变色锥(Castanopsis wattii)和南洋木荷(Schima noronhae), 它们同时也是该群落林冠层的优势树种。样地内所有个体的径级分布呈倒“J”型, 群落有充足的增补个体, 如蒙自连蕊茶和多花山矾等。稀有种(个体数少于20的物种)共计49种, 占总物种数的47.1%。常绿木本植物在样地内分别占总重要值、总多度和总胸高断面积的94.7%、96.2%和94.0%, 优势明显。
Aims: The mid-mountain moist evergreen broad-leaved forest is a montane forest vegetation type developed in the subtropical climate zones of China. However, the community structure of the forest has never been reported based on large sized plots. The present study investigated the tree species composition and community structure within a 20 hm 2 plot, serving as the fundamentals for analyzing the relationships between environmental factors and spatial distribution of tree species, and a basic platform for monitoring long-term forest dynamics in the future.
Methods: We established a 20 hm2 plot in a forest at Xujiaba on Mts. Ailaoshan, Jingdong County, Yunnan Province in 2014. The plot was set up in accordance to the protocols of the Center for Tropical Forest Science (CTFS). All free-standing woody plants with a diameter at breast height (DBH) ≥ 1 cm were positioned, mapped, tagged, measured and identified to species in the plot.
Important findings: A total of 44 168 free-standing individuals with DBH ≥ 1 cm were recorded, belonging to 104 species, 63 genera and 36 families. Trees of Fagaceae, Theaceae and Lauraceae are dominant species. At the level of genus, the floristic composition was primarily represented by both tropical (46.0%) and temperate (38.1%) elements. The 22 individual species with importance value ≥ 1 contributed 84.6% to the total abundance. The three most abundant species were Camellia forrestii, Vaccinium duclouxii and Symplocos ramosissima. Four tree species (Lithocarpus hancei, L. xylocarpus, Castanopsis wattii and Schima noronhae) had the largest basal areas, and they were also the dominant canopy tree species in the plot. The DBH distribution of all individuals in the plot showed a reversed “J” pattern, indicating numerous recruiting populations. Such a pattern was applicable to C. forrestii and S. ramosissima as well. Forty-nine rare species (those with individual number fewer than 20 in the plot) accounted for 47.1% of the species total. Evergreen species dominated the life form spectrum of the plot, making up for 94.7%, 96.2% and 94.0% in terms of importance value, total abundance and total basal area, respectively.
Abstract in Chinese and English; article in Chinese only.