DISSERTATION RESEARCH: Plant response to water availability and drought in a changing world

论文研究：变化世界中植物对水供应和干旱的反应

• 批准号: 1700855
• 负责人: Jennifer Powers
• 金额: $ 1.63万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-06-01 至 2019-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1700855&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Plant; response; water

Drought has been increasing in frequency and severity worldwide for the last 60 years, and the increase is expected to continue over the next several decades. Extreme drought events are already taking their toll on trees and other woody plants all over the world, leading to widespread forest mortality. As greenhouse gas emissions continue to rise on a global scale, the importance of forests increases, as trees can take up carbon dioxide and store it for centuries in the form of wood. However, the death of trees during drought reduces how much can be taken up and increases the amount of carbon dioxide released back into the air when dead trees decompose. This Doctoral Dissertation Improvement Grant will provide funds to evaluate which kinds of plants are more susceptible to drought, and the mechanisms that determine plants? vulnerability to extreme drought events. This research has the potential to reveal characteristics that make woody plants more or less tolerant to drought and may increase the ability to predict species? responses to extreme drought events. The results will inform local land managers and policy-makers on which tree species are more tolerant to drought and therefore improve plans for restoration and management of forests in the face of increasing drought severity. This project will use novel methods to determine the resistance of woody plants to extreme drought using plant anatomical features and physiological measurements. The major cause of tree mortality from drought is embolism accumulation in the water-conducting pipes of plants that obstruct proper water movement from the soil up to the leaves. The researchers will study which anatomical traits make plants more susceptible to embolisms. This work will be conducted in both dry and wet temperate and tropical forests to provide information on how plants growing under different rainfall environments respond to drought. The project will include workshops with public primary school teachers in rural Northwestern Costa Rica, which is an area with a history of extreme droughts that have resulted in widespread forest mortality. These workshops will enhance Costa Rican primary school curriculum through active learning of how plants obtain and use water and the impact of drought on native forests.

在过去的60年中，全球频率和严重程度的频率和严重程度一直在增加，预计在接下来的几十年中，这种增长将继续下去。极端的干旱事件已经使世界各地的树木和其他木本植物造成了损失，导致了广泛的森林死亡率。随着温室气体排放量继续在全球范围内上升，森林的重要性不断增加，因为树木可以占据二氧化碳并以木材形式储存数百年。但是，干旱期间树木的死亡减少了多少，可以增加多少二氧化碳的数量，当枯树分解时，释放了二氧化碳。 该博士学位论文改善赠款将提供资金来评估哪种植物更容易受到干旱的影响，以及确定植物的机制？极端干旱事件的脆弱性。这项研究具有揭示特征，使木本植物或多或少地容忍干旱，并可能增加预测物种的能力？对极端干旱事件的反应。结果将为当地土地管理者和政策制定者提供对干旱更宽容的耐受性，从而改善面对干旱严重程度日益严重的森林恢复和管理的计划。该项目将使用新颖的方法来确定木本植物使用植物解剖学特征和生理测量的抗性。干旱的树木死亡率的主要原因是栓塞在植物的水导管中积累，这些管道阻碍了从土壤到叶子向叶子移动的适当水。研究人员将研究哪些解剖特征使植物更容易栓塞。这项工作将在干燥的温带和热带森林中进行，以提供有关在不同降雨环境下生长的植物如何应对干旱的信息。该项目将包括与西北哥斯达黎加乡村的公立小学教师的讲习班，该地区是一个有极端干旱历史的地区，导致了广泛的森林死亡率。这些研讨会将通过积极学习植物如何获得和使用水以及干旱对本地森林的影响来增强哥斯达黎加小学课程。