Postdoctoral Fellowship: CREST-PRP: Ecophysiological response of tidal freshwater tree ecosystem engineers to chronic thermal, hydric, and salinity stressors in the Caribbean.

博士后奖学金：CREST-PRP：潮汐淡水树生态系统工程师对加勒比地区慢性热、水和盐压力源的生态生理反应。

• 批准号: 2400973
• 负责人: Elix Hernandez
• 金额: $ 30.71万
• 依托单位: University of Puerto Rico-Rio Piedras
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-07-01 至 2026-06-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2400973&HistoricalAwards=false
• 关键词: Postdoctoral; Fellowship; CREST; PRP; Ecophysiological

In tropical ecosystems the weather is typically stable and warm but in the past decade climate change has been causing changes in temperature and shifts in rain and sea level in coastal wetlands that are impacting tropical flora and fauna. Lacking tools to adjust to these changes, tropical plants might struggle to survive. This study will investigate how two tree species, Pterocarpus officinalis and Dalbergia ecastaphyllum, cope with changes in temperatures and water supply and how these changes are affecting their physiology. The study site is located in the Corredor Ecológico del Noreste, a natural reserve in the Caribbean that represents freshwater coastal wetlands. Working with natural resource managers, community, and scientists, data will be collected to characterize the effects of climate change on these trees with the goal of advance knowledging that can be applied to inform management decisions about coastal wetlands restoration.In the past decade, Puerto Rico and the broader Caribbean region have witnessed a historical increase in temperature. Trends suggest that this warming trajectory will continue, accompanied by other climatic extremes, including rising sea levels, extreme precipitation events, and intensified atmospheric disturbances. Coastal tropical vegetation is in a perilous situation, where in the context of a warmer planet and rising sea levels, vegetation might not have the physiological mechanisms for acclimation. This study’s goal is to assess the ecophysiological responses of nitrogen-fixing species in tidal freshwater wetlands in response to warmer temperatures and increased salinity under the same mesoclimate conditions. The research will investigate 1) how warmer climate and increased salinity affects photosynthesis and regulation of osmotic balance, and 2) how these environmental changes affect activity and efficiency of nitrogen fixation. Using an interdisciplinary approach involving plant physiology, ecology, climate change science and metabolomics, the study will include field observations of two tree species, Pterocarpus officinalis and Dalbergia ecastaphyllum, that share the same mesoclimate but different hydrologic conditions, and greenhouse experiments in which air temperature and saline conditions will be modified. Data examined will include light and temperature response curves to assess leaf thermal tolerance, plant morphological traits, hydraulic conductance, osmotic potential, 13C and 15N isotopic analyses for nitrogen fixation, as well as nutrient analysis and non-targeted metabolomic analyses to create a profile of metabolites related to salt stress and temperature changes. The combined approach will be applicable to informing plant selection in conservation management efforts, thus enhancing the potential benefits these critical ecosystems provide.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

在热带生态系统中，天气通常稳定且温暖，但是在过去的十年中，气候变化一直在导致沿海湿地的雨水和海平面变化，这些沿海湿地影响了热带动植物和动物群。缺乏适应这些变化的工具，热带植物可能难以生存。这项研究将研究两种树种，pterocarpus officinalis和dalbergia estaphyllum如何应对温度和供水的变化以及这些变化如何影响其生理。研究地点位于加勒比海的自然保护区CorredorEcológicodel Noreste，代表淡水沿海湿地。与自然资源经理，社区和科学家合作，将收集数据以表征气候变化对这些树木的影响，以便提前知道可以将有关沿海湿地恢复的管理决策提供信息。在过去的十年中，波多黎各Rico和更广泛的加勒比海地区已经见证了温度的历史升高。趋势表明，这种变暖轨迹将继续，伴随着其他极端极端，包括海平面上升，极端降水事件和受启发的大气障碍。沿海的热带植被处于危险的境地，在温暖的行星和海平面上升的情况下，植被可能没有适应物理机制。这项研究的目的是评估潮汐淡水湿地中氮固定物种的生态生物学反应，以响应温度较高的温度和在同一中性气候条件下的盐度升高。该研究将研究1）气候变暖和盐度增加如何影响光合作用和渗透平衡的调节，2）这些环境变化如何影响氮固定的活动和效率。使用涉及植物生理学，生态学，气候变化科学和代谢组学的跨学科方法，该研究将包括对两种树种的现场观察，即pterocarpus officinalis和dalbergia centaphylum，它们具有相同的中性气候但不同的水文条件，以及在其温度温度和盐水条件下进行修改的温室实验。研究的数据将包括光和温度响应曲线，以评估叶片热耐受性，植物形态性状，液压电导，渗透电势，13C和15N同位素分析，以固定氮，营养分析以及非靶向的代谢分析，以创建与盐胁迫和温度变化相关的分类材料的特征。合并的方法将适用于在保护管理工作中为植物选择提供信息，从而提高了这些关键生态系统提供的潜在利益。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子和更广泛影响的审查标准来通过评估来获得支持的。