BACKGROUND Acacia tortilis is a keystone species across arid ecosystems in Africa and the Middle East. Yet, its life-history, longevity and growth are poorly known, and consequently ongoing changes in tree populations cannot be managed in an appropriate manner. In other arid areas parenchymatic bands marking growth zones in the wood have made dendrochronological studies possible. The possibilities for using pre- and post-bomb 14C content in wood samples along with the presence of narrow marginal parenchymatic bands in the wood is therefore tested to gain further insight into the age, growth and growth conditions of A. tortilis in the hyper-arid Eastern Desert of Egypt. RESULTS Based on age scenarios and the Gompertz growth equation, the age of trees studied seems to be from 200 up to 650 years. Annual radial growth estimated from calibrated dates based on the post-bomb 14C content of samples is up to 2.4 mm, but varies both spatially and temporally. Parenchymatic bands are not formed regularly. The correlation in band pattern among trees is poor, both among and within sites. CONCLUSION The post-bomb 14C content of A. tortilis wood gives valuable information on tree growth and is required to assess the age scenario approach applied here. This approach indicates high longevities and slow growth of trees. Special management measures should therefore be taken at sites where the trend in tree population size is negative. The possibilities for dendrochronological studies based on A. tortilis from the Eastern Desert are poor. However, marginal parenchymatic bands can give insight into fine scale variation in growth conditions and the past management of trees.

中文翻译：

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金合欢的寿命和生长；来自 14C 含量和木材解剖学的见解。


背景 Acacia tortilis 是非洲和中东干旱生态系统的关键物种。然而，人们对它的生命史、寿命和生长知之甚少，因此无法以适当的方式管理树木种群的持续变化。在其他干旱地区，标记木材生长区域的薄壁组织带使树木年代学研究成为可能。因此，测试了使用木材样品中爆炸前和爆炸后 14C 含量以及木材中狭窄的边缘薄壁组织带的可能性，以进一步了解 A. tortilis 在超级环境中的年龄、生长和生长条件。埃及干旱的东部沙漠。结果 根据年龄情景和 Gompertz 生长方程，研究的树木年龄似乎为 200 至 650 年。根据样本爆炸后 14C 含量的校准日期估算出的年径向生长量高达 2.4 毫米，但在空间和时间上都有变化。薄壁组织带不规则形成。无论是在地点之间还是在地点之内，树木之间的带状图案的相关性都很差。结论 A. tortilis 木材的爆炸后 14C 含量提供了有关树木生长的宝贵信息，并且需要评估此处应用的年龄情景方法。这种方法表明树木的寿命较长但生长缓慢。因此，应在树木种群规模呈负趋势的地点采取特殊管理措施。基于东部沙漠的 A. tortilis 进行树木年代学研究的可能性很小。然而，边缘薄壁组织带可以洞察生长条件的精细尺度变化和过去的树木管理。