Collaborative Research: Climate-induced sea-level rise, warming and herbivory effects on vegetation and greenhouse gas emission in coastal western Alaska

北极沿海湿地正在经历气候变化的影响，包括气温变暖、海平面上升引发的洪水，以及夏季迁徙并以当地植物为食的鹅数量的变化。阿拉斯加的育空-库斯科维姆三角洲（Y-K）是世界上最大的河流三角洲之一，也是数百万候鸟的重要生态系统。这项研究着眼于变暖、洪水增加和鹅的影响变化将如何影响不同的植物群落和温室气体的吸收和释放，从而影响气候变化的速度。研究人员将在不同的植物群落中进行实地实验，这些植物群落将经历不同程度的洪水、变暖和鹅的影响，并测量植物和温室气体对这些变化的反应。研究人员还将进行实验室实验，在那里研究人员可以严格控制温度、洪水和鹅的影响，以更好地理解我们测量的现场反应背后的机制。这个项目扩展了我们的理解，因为它将在Y-K三角洲的沿海和内陆景观中进行，与之前的研究不同。这些实验将着眼于洪水、气候变暖和放牧鹅之间复杂的相互作用，以梳理这三种影响。这些实验提供的深刻理解也可以应用于其他生态系统，因为北极的许多沿海地区正在经历类似的气候变化。调查人员将与一名学校教师合作，根据这项研究建立学习模块，这些模块将用于Y-K三角洲土著村庄的中学。研究人员将在研究地点与当地高中生合作，培训他们实地技术，并帮助他们为当地广播电台编写有关研究的报道。最后，研究人员将培训和指导一名博士后研究员、两名研究生和三所大学的本科生，他们将通过科学会议和出版物传播他们的发现。北极沿海湿地正在经历气候变化的重大后果，包括气温升高、海平面上升和水禽丰度的变化。阿拉斯加的育空-库斯科维姆（Y-K）三角洲是世界上最大的河流三角洲之一，是数百万候鸟的重要避难所，也是北美最容易受到这些变化影响的地区之一。该提案的总体目标是研究在水禽数量变化的情况下，温度升高和洪水如何相互作用，影响Y-K三角洲地区的植物群落和温室气体（GHG）排放，特别是二氧化碳和甲烷。为了实现这一目标，研究人员将进行大规模的野外实验，在那里他们将操纵温度、洪水状况和鹅的影响，以量化这些变量如何相互作用来影响植物群落和温室气体通量。研究人员将使用实验室实验来扩展对测量反应背后机制的推断和理解。这些方法的结合将使我们更好地了解是什么驱动了植被群落动态和该系统的温室气体排放。本研究解决了三个知识空白：1)通过测量沿海和内陆植物群落对温室气体的控制，扩展了我们对Y-K三角洲温室气体通量的认识；2)研究结果将为预测未来气候变化如何相互作用影响群落和温室气体通量提供信息；3)通过提高对不同条件下驱动温室气体通量的机制的理解，该工作将提高对其他高纬度沿海湿地系统中气候变化如何影响温室气体通量的理解。为了产生更广泛的影响，调查人员将与一名当地学校教师合作，根据我们的研究构建学习模块，用于Y-K三角洲土著村庄的中学。调查人员将在研究地点与当地高中生合作，培训他们实地技术，并帮助他们为当地广播电台编写有关研究的报道。研究人员将培训和指导一名博士后研究员、两名研究生和三所大学的本科生，他们将通过科学会议和出版物传播他们的发现。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Arctic coastal wetlands are experiencing the effects of climate change, including warming temperatures, flooding from sea level rise, and changes to the number of geese that migrate in the summer and graze on local plants. The Yukon-Kuskokwim (Y-K) Delta of Alaska is one of the largest river deltas in the world and an important ecosystem for millions of migratory geese. This research looks at how warming, increased flooding, and changes in the impacts of geese will affect different plant communities and the uptake and release of greenhouse gases, which influence the rate of climate change. The investigators will conduct field experiments in different plant communities that will experience different levels of flooding, warming, and goose impacts, and measure plant and greenhouse gas responses to these changes. The investigators will also conduct laboratory experiments where the investigators can tightly control temperature, flooding, and effects of geese to better understand the mechanisms behind our measured field responses. This project expands our understanding because it will be conducted across both coastal and inland landscapes in the Y-K Delta, unlike previous research. The experiments will look at complex interactions between flooding, warming, and goose grazing to tease apart these three effects. The deep understanding provided from these experiments can also be applied to other ecosystems because many coastal regions in the Arctic are experiencing similar climate changes. The investigators will work with a school teacher to build learning modules based on this research that will be used in middle schools across native villages in the Y-K Delta. The researchers will work with local high school students at the research site to train them in field techniques as well as help them develop a story about the research for the local radio station. Finally, the investigators will train and mentor a post-doctoral researcher, two graduate students, and undergraduates at three universities, who will disseminate their findings through scientific conferences and publications. Arctic coastal wetlands are experiencing significant consequences of climate change, including increasing temperature, rising sea level, and changing waterfowl abundances. The Yukon-Kuskokwim (Y-K) Delta in Alaska, one of the largest river deltas in the world, is an important refuge for millions of migratory birds and one of the most vulnerable regions in North America to these changes. The overall goal of this proposal is to investigate how increasing temperature and flooding, in light of changing waterfowl abundances, interact to affect plant communities and greenhouse gas (GHG) emissions, specifically carbon dioxide and methane, across the Y-K Delta landscape. To address this goal, the investigators will conduct a large-scale field experiment, where they will manipulate temperature, flooding regimes, and goose impacts to quantify how these variables interact to influence plant communities and GHG fluxes. The investigators will use laboratory experiments to expand inference and understanding of the mechanisms behind the measured responses. The combination of these approaches will result in a greater understanding of what drives vegetation community dynamics and GHG emissions from this system. The proposed research addresses three gaps in knowledge: 1) This research expands our knowledge about GHG fluxes in the Y-K Delta by measuring the controls on GHGs in both coastal and inland plant communities; 2) The results will inform prediction of how climate-induced changes will interact to influence communities and GHG fluxes in the future; and 3) By improving understanding of the mechanisms that drive GHG fluxes across a gradient of conditions, the work will improve understanding of how GHG fluxes will be affected by climate change in other high-latitude coastal wetland systems. For broader impacts, the investigators will work with a local school teacher to build learning modules from our research to be used in middle schools across native villages in the Y-K Delta. The investigators will work with local high school students at the research site to train them in field techniques as well as help them develop a story about the research for the local radio station. The investigators will train and mentor a post-doctoral researcher, two graduate students, and undergraduates at three universities, who will disseminate their findings through scientific conferences and publications.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.