几十年的碳储量在树种中普遍存在,仅受树长寿的限制
Drew M P Peltier1, Mariah S Carbone2,3, Kiona Ogle2,3,4
1School of Life Sciences, University of Nevada, Las Vegas, Las Vegas, NV, 89154, USA.
The New phytologist
|December 3, 2024
概括
树木存储不同年龄的碳储量,从最近到几十年的碳储量,同时在树干中. 像火灾这样的干扰显著地使这些储备变老,而环境压力对物种的影响不同.
科学领域:
- 植物生理学 植物生理学
- 生态生态学 生态生态学
- 通过放射性碳测年法进行测年.
背景情况:
- 植物从过去的光合作用中储存碳储备,以推动当前的新陈代谢.
- 树干储备与大气炸弹尖峰的放射性碳 (Δ14C) 约会揭示了储备年龄.
研究的目的:
- 综合来自九种树木的Δ14C数据,以建模储备的动态.
- 调查储备的分布,混合和周转在物种之间以及应对压力 (干旱,干旱) 和干扰 (火灾,树皮甲虫) 时如何变化.
主要方法:
- 合成了来自九种树干储备的现有放射性碳 (Δ14C) 数据.
- 开发并应用了一种新的流程模型来分析储备积累,分配,混合和营业额.
- 检查了环境压力和干扰对保护区特征的影响.
主要成果:
- 年轻的 (<1岁) 和老的 (20-60岁以上) 储量在单一树木中共存,包括针叶树中的前爆碳.
- 该模型显示储备的深度混合 (平均约30个环),周转时间约为2.7年.
- 干扰显著增加了储备年龄 (+15-35年),而压力影响是物种特异性的;一些物种在恢复过程中显示出老储备的外向混合.
结论:
- 大多数光合作用物被快速代谢,由深度混合和储备的快速循环证明.
- 储备年龄的生态变化很大,可能受到压力和干扰的影响.
- 最大储备年龄主要受到树木长寿的限制,这表明旧储备在树木中普遍存在.
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