Tree ring analysis reveals age structure, dynamics and wood production of a natural forest stand in Cameroon
Tree ring analysis reveals age structure, dynamics and wood production of a natural forest stand in Cameroon
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DOI：
10.1016/s0378-1127(01)00814-3
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发表时间：
2003-02
影响因子：
3.7
通讯作者：
M. Worbes;R. Staschel;A. Roloff;W. Junk
中科院分区：
文献类型：
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作者：
M. Worbes;R. Staschel;A. Roloff;W. Junk
在喀麦隆的一个半落叶天然林中，在1公顷的面积上对直径大于10厘米的所有树木进行了森林调查和生长量估计。该林分主要由Triplochiton scleroxylon组成，是广泛分布于西非的森林类型的一部分。放射性碳测年和树木年轮分析证明树木木材中存在年轮。最古老的树（Celtis zenkeri）的立场是220岁。41 - 60岁年龄组的个体数量最多。120多岁的树木被发现专门在层的Emercury。树木的年龄与直径和高度的相关性很弱。林下树种的平均直径生长率为0.2cm/年，挺水树种为0.82cm/年。主要用材树种（T. 90年平均最小采伐直径为80 cm。根据种群的年龄、高度分布和木材密度，将种群的生存策略分为三种类型。在各龄级中具有高木材密度和低生长率的树种一般仅限于林下层。只有老个体、低或中等木材密度和高生长率的树种仅限于上层，可归类为长寿先锋树种（T。硬木属）。最后，具有中等或高木材密度的物种，上层的一些老个体和下层冠层的许多新兵可以被定义为成熟的森林树木或未来的树木（Nesogordonia papaverifera，梧桐）。这些研究结果导致的假设，调查的立场可以被归类为一个很晚的次生林过渡到成熟的森林。
In a semi-deciduous natural forest stand in Cameroon a forest inventory and increment estimations on all trees with a diameter above 10cm were carried out in an area of 1ha. The stand is dominated by Triplochiton scleroxylon and is a part of a forest type which is widely distributed in West Africa. The existence of annual rings in the wood of trees was proven by radiocarbon dating and tree ring analysis. The oldest tree (Celtis zenkeri) of the stand was 220 years old. The age class between 41 and 60 years is the strongest in number of individuals. Trees with an age of more than 120 years were found exclusively in the storey of the emergents. The age of the trees correlates very weakly with the diameter and the height. The mean diameter growth rates vary between 0.2cm per year in understorey tree species and 0.82cm per year in emergent species. The major timber species (T. scleroxylon) reaches in mean the minimum felling diameter of 80cm within 90 years. According to their age and height distribution together with the wood density, we distinguished three major types of life strategies of species cohorts. Species with high wood density and low increment rates in all age classes are generally restricted to the understorey. Species with exclusively old individuals, low or moderate wood densities and high increment rates are restricted to the upper storey and can be classified as long-living pioneers (T. scleroxylon). Finally, species with moderate or high wood density, some old individuals in the upper storey and many recruits in the lower canopy can be defined as mature forest trees or trees of the future (Nesogordonia papaverifera, Sterculia rhinopetala). These findings lead to the assumption that the investigated stand can be classified as a very late secondary stand in transition to a mature forest.