The effect of severe drought on CO2 uptake by plants and carbon dynamics in the plant-soil system

严重干旱对植物吸收二氧化碳和植物-土壤系统碳动态的影响

基本信息

批准号：
230374803
负责人：
Professor Dr. Bruno Glaser
金额：
--
依托单位：
Lehrstuhl für Störungsökologie
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2012
资助国家：
德国
起止时间：
2011-12-31 至 2014-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/230374803?language=en
关键词：
effect severe drought CO2 uptake

项目摘要

Drought events are regarded to increase in frequency and duration due to climate change. Especially, severe droughts most likely increase in Germany during summer season, where commonly plants actively grow and assimilate CO2, which can be strongly affected by drought. As the latter effect strongly depends on physiology of plants and drought resistance, more drought tolerant plants are thought to further assimilate CO2, while others die. This has a strong influence on the plant driven sequestration of C in soil and thus the C fluxes in the plant-soil system as drought might also promotes C loss in soil. Furthermore, it remains questionable, if plants are able to adapt to drought to further resist to severe droughts.In the current proposal, we will proof CO2 uptake by plants, translocation of C from plants to soil and soil C fluxes of two different plant communities (grass and heath), which were previously exposed to annual drought or control conditions, as affected by increasing drought. This will be traced in a triple 13CO2 pulse experiment, which was carried out under rainout shelters installed on the Bayreuth EVENT I experiment in summer 2011. After each 13CO2 labeling, carried out in weeks 1, 5, 9 after the installation of the rainout shelters, plant and soil samples were collected weekly, thus enabling 13C tracing in the individual plant compartments and soil, which is compared to replicates that did not receive the isotopic label.This research will serve the following central goals: 1. Determine effect of increasing drought on C uptake by plants and C translocation towards soil. 2. Identify plant species of lower or higher drought tolerance in both plant communities. 3. Assess the effect of severe drought on soil C storage. Such information is strongly required to understand plant community responses and carbon budgets in the plant-soil system as under future climatic conditions.

由于气候变化，干旱事件被认为增加了频率和持续时间。特别是，在夏季，德国最有可能增加的干旱，那里通常植物会积极生长和吸收二氧化碳，这可能会受到干旱的强烈影响。由于后者的作用在很大程度上取决于植物和抗旱性的生理学，因此人们认为更耐旱的植物可以进一步同化二氧化碳，而其他植物则死亡。这对植物驱动的C在土壤中的隔离有很大影响，因此，由于干旱也可能促进土壤中的植物土壤系统中的C通量。此外，如果植物能够适应干旱以进一步抵抗严重的干旱。在当前的提案中，我们将证明植物的二氧化碳吸收，C植物从植物到土壤和土壤C的易位，以及两个不同植物群落的土壤c通量（草和荒地）以前暴露于每年的干旱或控制条件下，受干旱的影响。这将在三重13CO2 Pulse实验中追踪，该实验是在2011年夏季实验的Rainout避难所下进行的。在安装RainOut避难所后，在第1、5、9周进行了每个13CO2标签之后，每周收集植物和土壤样品，从而在单个植物室和土壤中进行13C追踪，将其与未接受同位素标签的复制进行了比较。这项研究将达到以下中心目标：1。确定干旱的影响。在植物的C摄取和c转移到土壤上。 2。确定两个植物群落中较低或更高干旱耐受性的植物物种。 3。评估严重干旱对土壤C储存的影响。在未来的气候条件下，强烈需要此类信息才能了解植物土壤系统中的植物社区反应和碳预算。