稳定同位素标签揭示了芽前温带树苗中的水和碳流
Manuel G Walde1, Marco M Lehmann1, Arthur Gessler1,2
1Ecosystem Ecology, Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland.
Plant, cell & environment
|October 1, 2024
概括
温带树在冬季休眠期间吸收土壤和大气中的水,以便在春季早期得到水分. 常青树苗还吸收大气中的碳,突出了生长季节前物种特定的水和碳动态.
科学领域:
- 植物生理学 植物生理学
- 森林生态 森林生态
- 同位素生物地质化学 同位素生物地质化学
背景情况:
- 了解冬季休眠期间温带树木的水和碳动态对于预测森林对气候变化的反应至关重要.
- 在生长季节开始之前,关于控制这些过程的生理机制的知识有限.
研究的目的:
- 研究温带树种在从冬季休眠期过渡到初春期间的水和碳吸收和分配策略.
- 阐明土壤水和大气中的水蒸气吸收在保持树木水分的作用.
主要方法:
- 在冬季休眠期间将 (2H) 丰富水应用于土壤中.
- 在强迫条件下测量植物组织 (茎,枝,芽) 中的同位素.
- 用2H丰富的水蒸气和碳-13 (13C) 丰富的二氧化碳进行脉冲标记,以追踪大气吸收.
主要成果:
- 土壤水在休眠期间被纳入地表器官,并在强迫条件下不同地分配给物种.
- 所有测试的物种都将大气中的水蒸气吸收到地表组织中.
- 从大气中的二氧化碳中吸收的碳仅在常青树苗中观察到.
结论:
- 温带树在冬季积极吸收和重新分配土壤水.
- 大气中的水蒸气吸收有助于温带树木的地面水合.
- 水和碳动态的特定物种差异受结构特征和常青与落叶的习惯的影响.
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