Integration of plant responses to multiple stressors over time: interactions between winter and summer

随着时间的推移植物对多种应激源的反应的整合：冬季和夏季之间的相互作用

基本信息

批准号：
RGPIN-2015-06178
负责人：
Henry, Hugh
金额：
$ 3.57万
依托单位：
University of Western Ontario
依托单位国家：
加拿大
项目类别：
Discovery Grants Program - Individual
财政年份：
2019
资助国家：
加拿大
起止时间：
2019-01-01 至 2020-12-31
项目状态：
已结题

来源：
https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=689778
关键词：
Integration plant responses multiple stressors

项目摘要

Response to multiple stresses has been a key topic in plant research, particularly in the context of global environmental change. While there has been a focus on plant responses to stresses that occur simultaneously, such as drought and heat stress, interactions between stresses also can occur sequentially in time. In some cases changes in the physiology of a plant in response to an initial stress can decrease vulnerability to future stress. However, in contrast to the potential benefits of this 'stress memory,' declines in plant condition in response to the initial stress can decrease the ability to tolerate future stress. Such interactions between multiple stresses have been studied extensively in the context of the growing season. In contrast, studies of carryover effects of winter stress on summer stress responses are lacking, despite the potential for variability in winter conditions to influence plant growing season performance substantially. Synergies between plant responses to variability in winter conditions and stress tolerance over summer are further complicated when examined in an ecosystem context. For example, frost not only has the potential to damage overwintering plants, but it also can affect soil microorganisms, nutrient availability, soil physical properties and moisture, and the interactions of these factors need to be accounted for when examining overall plant responses. ***The overarching question I will address with my research program is how variability in winter conditions alters the subsequent responses of herbaceous plants to stress over summer. I hypothesize that while frost damage over winter can reduce the performance of plants over summer, exposure to stress over winter nevertheless has the potential to reduce the vulnerability of plants to summer stresses. I will test this hypothesis and explore how soil processes can contribute to interactions between winter conditions and summer stress using a combination of controlled environment and field experiments. My short term objective is to examine how the timing and severity of frost exposure affect summer drought tolerance, the importance of direct effects versus the indirect effects in explaining interactions between frost and drought, and the performance tradeoffs that limit the abilities of plants with high stress memory to capitalize on extended growing season length. My long term objective is to examine the broader significance of plant winter/summer stress interactions in influencing plant community and ecosystem level processes, including plant species composition, soil nitrogen availability and retention, and plant litter decomposition. In terms of impact, my research will provide crucial information for predicting changes in species distributions and ecosystem function in response to extreme climate events, and transform how winter processes are integrated into plant and ecosystem ecology. *** **

对多种压力的反应一直是植物研究中的一个关键主题，尤其是在全球环境变化的背景下。虽然一直关注简单发生的植物对应激的反应，例如干旱和热应激，但应力之间的相互作用也可以依次及时发生。在某些情况下，由于初始压力，植物生理学的变化会减少对未来压力的脆弱性。但是，与这种“压力记忆”的潜在益处相反，植物状况下的响应初始压力的下降可以降低忍受未来压力的能力。在生长季节的背景下，已经对多种压力之间的这种相互作用进行了广泛的研究。相比之下，尽管缺乏对冬季压力对夏季压力反应的结转影响的研究，尽管冬季条件下有可能影响植物生长季节的表现，但仍缺乏对夏季压力反应的反应。在生态系统环境中检查植物对变异性的植物对变异性的反应与夏季的压力耐受性之间的协同作用更加复杂。例如，弗罗斯特不仅有可能损害越冬的植物，而且还会影响土壤微生物，养分可用性，土壤物理特性和水分，并且在检查整体植物反应时需要考虑这些因素的相互作用。 ***我将在研究计划中解决的总体问题是，冬季条件下的可变性如何改变草本植物对夏季压力的随后反应。我假设，尽管冬季的霜冻破坏可以在夏季降低植物的性能，但是在冬季承受压力的可能性仍然有可能减少植物在夏季压力下的脆弱性。我将检验这一假设，并探讨土壤过程如何使用受控环境和现场实验的结合来促进冬季条件与夏季压力之间的相互作用。我的短期目标是检查霜冻暴露的时间和严重程度如何影响夏季的干旱耐受性，直接影响与间接影响在解释霜冻与干旱之间的相互作用方面的重要性以及限制具有高压力记忆力的植物能力以利用扩展生长季节长度的植物的能力。我的长期目标是研究影响植物社区和生态系统水平过程的植物冬季/夏季压力相互作用的更广泛的意义，包括植物物种组成，土壤氮的可用性和保留率以及植物垃圾分解。在影响方面，我的研究将提供至关重要的信息，以预测响应极端气候事件的物种分布和生态系统功能的变化，并将冬季过程整合到植物和生态系统生态学中。 *******