Water isotopes in desiccating lichens
Water isotopes in desiccating lichens
复制标题
干燥地衣中的水同位素
作者：
Britta Hartard;M. Cuntz;C. Máguas;M. Lakatos
水的稳定同位素组成通常被用作维管植物和生态系统中水交换过程的示踪剂。到目前为止，还没有研究集中在非维管生物，多水生物，如地衣和苔藓植物的同位素过程。为了了解非维管植物的基本同位素交换过程，研究了不同种类的绿藻地衣在干燥条件下的菌体水同位素组成。研究表明地衣与周围水蒸气的同位素组成平衡。开发了一个模型作为概念的证明，该模型说明了这些多水生物的特定水关系。该方法首先结合了它们可变的菌体水势，然后将菌体水划分为两个同位素不同但相连的水池。此外，这些结果代表了向发展多氢生物作为环境蒸气同位素组成记录者迈出的第一步。
The stable isotopic composition of water is routinely used as a tracer to study water exchange processes in vascular plants and ecosystems. To date, no study has focussed on isotope processes in non-vascular, poikilohydric organisms such as lichens and bryophytes. To understand basic isotope exchange processes of non-vascular plants, thallus water isotopic composition was studied in various green-algal lichens exposed to desiccation. The study indicates that lichens equilibrate with the isotopic composition of surrounding water vapour. A model was developed as a proof of concept that accounts for the specific water relations of these poikilohydric organisms. The approach incorporates first their variable thallus water potential and second a compartmentation of the thallus water into two isotopically distinct but connected water pools. Moreover, the results represent first steps towards the development of poikilohydric organisms as a recorder of ambient vapour isotopic composition.
影响因子：
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作者：
D. Silverman
通讯作者：
D. Silverman