Collaborative Research: Permafrost climate feedbacks: How interactions among plants, microbes, and minerals affect biogeochemical projections in a changing Arctic

合作研究：永久冻土气候反馈：植物、微生物和矿物质之间的相互作用如何影响不断变化的北极的生物地球化学预测

• 批准号: 2031072
• 负责人: Caitlin Hicks Pries
• 金额: $ 32.08万
• 依托单位: Dartmouth College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-01-01 至 2024-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2031072&HistoricalAwards=false
• 关键词: Collaborative; Research; Permafrost; climate; feedbacks

The Arctic is warming at a rate faster than elsewhere on Earth, resulting in changes to Arctic ecosystems that may affect global climate. Permafrost is ground that remains frozen for at least two consecutive years. It occurs under approximately one fourth of the northern hemisphere's land surface and contain as much carbon as the entire atmosphere. Permafrost thaw leads to changes in the dominant vegetation and makes the carbon stored in the permafrost soil vulnerable to decomposition, but existing measurements and models disagree about the implications of these changes for the global carbon cycle. This research project investigates how processes mediated by microbes, minerals, and their interactions with vegetation affect the vulnerability of carbon in permafrost soils. The researchers are carrying out laboratory and growth chamber studies to investigate microbial communities and the transformations of carbon with permafrost thaw. They are incorporating the results of those studies into Earth system models to understand feedbacks to the climate system. This research is addressing critical knowledge gaps about how carbon stored in frozen permafrost will affect the Earth's carbon cycle, which is information urgently needed to inform climate change adaptation and mitigation strategies.This project is addressing the question: how will feedbacks between plants and soils (specifically minerals and microbes) affect arctic soil carbon balance in response to global change? Using state-of-the-science tools, such as microbial sequencing and stable isotope tracing, the researchers are carrying out (1) laboratory incubations to determine how soil microbial communities and mineralogy affect the fate of plant exudates and the vulnerability of native soil organic matter in thawed permafrost, and (2) plant-soil growth chamber mesocosms to trace belowground plant deposits into permafrost soils under ambient and elevated CO2. These findings are being used to develop and evaluate a microbial-enabled model that can handle the complexity of plant-microbe-mineral feedbacks. This soil model is being integrated into the Community Land Model (CLM) to predict the impact of permafrost thaw on the arctic carbon budget. This research enables better long-term projections of permafrost-climate feedbacks. The project is training the next generation of interdisciplinary Arctic scholars well-versed in scales ranging from microbial genes to global elemental cycles through PhD assistantships, postdoctoral research, and undergraduate laboratory education. In addition, the project provides training for up to 50 early career researchers on the theory and practice of land modeling, with a special focus on Arctic systems.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.

北极的变暖速度比地球上其他地方的速度快，从而导致可能影响全球气候的北极生态系统的变化。永久冻土是至少连续两年保持冷冻的地面。它发生在北半球陆地表面的大约四分之一之下，并含有与整个大气一样多的碳。 永久冻结融化会导致主要植被的变化，并使碳储存在永久冻土土壤中很容易被分解，但是现有的测量和模型对这些变化对全球碳循环的影响不同意。 该研究项目研究了微生物，矿物质及其与植被的相互作用如何影响碳在多年冻土土壤中的脆弱性。 研究人员正在进行实验室和生长室研究，以调查微生物群落和碳的转化，并用永久冻结。他们将这些研究的结果纳入地球系统模型中，以了解气候系统的反馈。这项研究正在解决有关如何在冷冻多年冻土中储存的碳将影响地球周期的关键知识差距，这是迫切需要的信息，以告知气候变化适应和缓解策略。该项目正在解决以下问题：植物和土壤之间的反馈将如何影响ARCTIC土壤碳平衡响应全球变化？研究人员使用最先进的工具，例如微生物测序和稳定的同位素追踪，进行（1）实验室孵化，以确定土壤微生物群落和矿物学如何影响植物散发物的命运，以及渗透性的生长室中廉价的植物和（2）下面的植物植物，（2）下面的植物植物序列，（2）生长室（2）下面的植物。高架二氧化碳。这些发现被用来开发和评估具有微生物的模型，该模型可以处理植物 - 微生物反馈的复杂性。该土壤模型正在整合到社区土地模型（CLM）中，以预测永久冻结对北极碳预算的影响。这项研究可以更好地对多年冻土气候反馈的长期预测。该项目正在培训下一代跨学科的北极学者，通过博士学位助理，博士后研究和本科实验室教育，范围从微生物基因到全球元素周期等等。此外，该项目为50名早期职业研究人员提供了关于土地建模理论和实践的培训，特别关注北极系统。该奖项反映了NSF的法定任务，并被认为是通过基金会的知识分子和更广泛影响的评估审查标准来通过评估来获得支持的。