Collaborative Research: Drivers and Biogeochemical Implications of Saltwater Intrusion Along Arctic Coastlines

合作研究：北极海岸线盐水入侵的驱动因素和生物地球化学影响

• 批准号: 2316041
• 负责人: James McClelland
• 金额: $ 43.41万
• 依托单位: Marine Biological Laboratory
• 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: 2024-04-01 至 2027-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2316041&HistoricalAwards=false
• 关键词: Collaborative; Research; Drivers; Biogeochemical; Implications

Sea-level rise and storm events push saltwater landward (i.e., saltwater intrusion), driving changes in the chemistry, ecology, and greenhouse gas fluxes of terrestrial ecosystems. Present knowledge of the drivers and impacts of saltwater intrusion is based on temperate and tropical environments. Little is known about saltwater intrusion along Arctic coastlines where permafrost underlies coastal ecosystems. In this study, we investigate the drivers of coastal Arctic saltwater intrusion and the impacts of saltwater intrusion on porewater chemistry and greenhouse gas fluxes along Alaska’s Beaufort Sea coast. This work will provide baseline understanding of the physical, biological, and chemical processes occurring along rapidly changing Arctic coastlines; will train two summer interns, a research assistant, and field technician; and will fund two early career, female researchers. Findings will be shared with the scientific community, as well as at local schools and public forums, bringing the Arctic to Cape Cod communities. Along coastlines worldwide, sea-level rise and storm events are driving saltwater intrusion into terrestrial environments. Present understanding of the drivers and ecosystem ramifications of saltwater intrusion is largely based on studies conducted in temperate and tropical environments. The influence of saltwater intrusion on the physical and biogeochemical properties of permafrost-bound coastlines has been investigated far less, leaving pronounced gaps in understanding of coastal Arctic ecosystem responses to salinization. This study will fill these gaps by expanding knowledge of the processes mediating distributions of coastal porewater salinity and the consequences of Arctic tundra salinization for greenhouse gas fluxes to the atmosphere and nutrient fluxes to the coastal ocean. Through an interdisciplinary field and laboratory study conducted along Alaska’s Beaufort Sea coast, we will (1) characterize subsurface temperature, water level, thaw depth, and porewater salinity dynamics, (2) measure porewater nutrient concentrations and greenhouse gas fluxes, and (3) assess links between water table dynamics, groundwater nutrient concentrations, and greenhouse gas fluxes across healthy and salinized tundra sites. The proposed activities will expand system understanding by uncovering links between tundra salinization and altered physical and biogeochemical processes, enhancing our ability to project coastal ecosystem function in a changing climate. The broader impacts of the project include early career mentorship, participation in K-12 education, and research dissemination to the scientific and broader community. Specifically, this project will train summer interns, a research assistant, and a technician both in the field and laboratory. Through partnerships with the Woods Hole Science and Technology Education Program, project outcomes will regularly be presented at local schools and public forums, and PIs will participate in local activities including mentoring student projects in science fairs. Lastly, results from this project will be disseminated to the scientific community through journal publications and conference presentations.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.

海平面的上升和风暴事件推动了盐水陆地（即盐水入侵），推动陆地生态系统的化学，生态学和温室气体通量的变化。目前了解盐水侵入的驱动因素和影响是基于温度和热带环境。关于北极海岸线上的盐水侵入知之甚少，北极冻土是沿海生态系统基础的基础。在这项研究中，我们调查了沿海北极盐水入侵的驱动因素以及盐水侵入对阿拉斯加Beaufort Sea Coast沿线沿孔水化学和温室气体通量的影响。这项工作将提供对沿北极海岸线快速变化的物理，生物和化学过程的基线理解。将培训两个暑期实习生，一名研究助理和现场技术员；并将资助两个早期职业，女性研究人员。调查结果将与科学界以及当地学校和公共论坛共享，将北极带到鳕鱼角社区。沿着全球海岸线，海平面上升和风暴事件正在推动盐水侵入陆地环境。目前对盐水侵入的驱动因素和生态系统分析的了解主要基于在温度和热带环境中进行的研究。盐水侵入对永久冻土沿岸海岸线的物理和生物地球化学特性的影响较小，在理解沿海北极生态系统对盐分的反应方面留下了明显的差距。这项研究将通过扩大对沿海毛水盐度的分布的知识的了解，以及北极苔原盐水对温室气体通量到大气的后果以及对沿海海洋的营养通量的后果。 Through an interdisciplinary field and laboratory study conducted along Alaska’s Beaufort Sea coast, we will (1) characterize subsurface temperature, water level, thaw depth, and porewater salinity dynamics, (2) measurement porewater nutrient concentrations and greenhouse gas fluxes, and (3) assessment links between water table dynamics, groundwater nutrient concentrations, and greenhouse gas fluxes across healthy and salinized tundra站点。拟议的活动将通过发现苔原盐化和改变物理和生物地球化学过程之间的联系来扩展系统理解，从而增强我们在不断变化的气候下投射沿海生态系统功能的能力。该项目的广播公司影响包括早期职业心态，参与K-12教育以及对科学和广播公司社区的研究。具体来说，该项目将培训暑期实习生，研究助理以及实验室和实验室的技术。通过与Woods Hole Science和技术教育计划的合作伙伴关系，项目成果将定期在当地学校和公共论坛上介绍，PIS将参加当地活动，包括在科学博览会上进行心理学生项目。最后，该项目的结果将通过期刊出版物和会议演讲将科学界传播到科学界。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优点和更广泛的影响评估标准通过评估而被认为是珍贵的支持。