Estimating fluxes of CO2 and CH4 along the Siberian Yensei River

估算西伯利亚延塞河沿线的 CO2 和 CH4 通量

• 批准号: 1642851
• 负责人: Rainer Amon
• 金额: $ 4.95万
• 依托单位: Texas A&M University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-06-15 至 2017-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1642851&HistoricalAwards=false
• 关键词: Estimating; fluxes; CO2; CH4; along

The proposed work will explore the release of greenhouse gases from Arctic rivers to the atmosphere. The hypothesis of this work is that land-based organic carbon that gets flushed into rivers does not makes its way to the Arctic Ocean, where it could be deposited in the sediments. Rather, before reaching the Arctic Ocean, microbes decompose this organic carbon, resulting in a flux of CO2 and CH4, both greenhouse gases, from the rivers to the atmosphere. The larger concern is that as Arctic peatlands warm and thaw over this century, organic material that has built up over thousands of years in the frozen soils will become susceptible to transport to the rivers, processing, and then released to the atmosphere in the form of CO2 and CH4. Currently this is an under-explored research topic, partly because it is so difficult to directly measure the transfer of these greenhouse gases from the rivers to the atmosphere. The PIs of this project believe that they have developed the instrumentation to estimate these fluxes in a cheap and reasonable way. The PI intends to do this in a Russian watershed. As the cruise expenses will be paid by their Russian collaborators, the PIs are asking for a small amount of support funds to develop the instruments and for travel.This is a relatively small project and only includes for 1 month participation of a graduate student. However, the collaboration with foreign colleagues is viewed very positively. Moreover, Amon has a good track record with respect to BI and outreach. In previous work, Amon has trained several graduate students and exposed a number of undergraduate students to Arctic research. He has organized a data workshop with international participation including several graduate and undergraduate students at the TAMU international study center in Italy and initiated the ?science on the island? series to published short newspaper articles about these research projects in the Galveston County Daily News. The Program has no reason to believe that this commitment to active outreach and education will cease.The watersheds of the large Siberian rivers store significant amounts of organic carbon in soils and vegetation. However, the lateral transport of carbon from Arctic lands to the rivers, the in-stream processing of DOC, and the greenhouse gas evasion from the river networks has not been well determined. In the summer of 2015, dissolved organic carbon (DOC) measured in the Yenesei by Amon and colleagues indicates large differences in upstream and downstream DOC during the freshet period, suggesting 1) significant in-transit losses of DOC and 2) that plant and litter carbon is the predominant source of DOC exported to the Arctic Ocean. The proposed project will measure the concentration and isotopic composition of CO2 and CH4 in surface waters and air, which, together with other measurements, will permit the determination of air/water gas exchange. This award will allow the PIs to take advantage of an offer to participate in a cruise of opportunity on a 2000 km stretch of the Yenisei River in the summer 2016.

拟议的工作将探索北极河流向大气中排放的温室气体。 这项工作的假设是，冲入河流的陆地有机碳不会进入北冰洋，在那里它可能沉积在沉积物中。 相反，在到达北冰洋之前，微生物会分解这些有机碳，导致二氧化碳和甲烷（这两种温室气体）从河流进入大气。 更大的担忧是，随着北极泥炭地在本世纪变暖和解冻，在冻土中积累了数千年的有机物质将变得容易被运输到河流、加工，然后以二氧化碳和甲烷。 目前，这是一个尚未充分探索的研究课题，部分原因是直接测量这些温室气体从河流到大气的转移非常困难。 该项目的 PI 相信他们已经开发出了能够以廉价且合理的方式估算这些通量的仪器。 PI 打算在俄罗斯的一个分水岭进行这项工作。 由于巡航费用将由俄罗斯合作者支付，PI 正在寻求少量支持资金来开发仪器和旅行。这是一个相对较小的项目，仅包括一名研究生参与 1 个月的时间。 然而，与外国同事的合作却受到非常积极的评价。此外，Amon 在 BI 和外展方面拥有良好的记录。 在之前的工作中，阿蒙培养了几名研究生，并让一些本科生接触了北极研究。 他在意大利 TAMU 国际研究中心组织了一次有国际参与的数据研讨会，其中包括几名研究生和本科生，并发起了“岛上的科学”活动。系列在加尔维斯顿县每日新闻上发表有关这些研究项目的短报文章。 该计划没有理由相信这种对积极宣传和教育的承诺将会停止。西伯利亚大河的流域在土壤和植被中储存了大量的有机碳。 然而，碳从北极陆地到河流的横向输送、DOC的河内处理以及河流网络的温室气体逃逸尚未得到很好的确定。 2015 年夏季，Amon 及其同事在叶尼塞河中测量的溶解有机碳 (DOC) 表明，淡水期间上游和下游 DOC 存在巨大差异，这表明 1) DOC 在运输过程中显着损失，2) 植物和凋落物碳是出口到北冰洋的DOC的主要来源。拟议项目将测量地表水和空气中二氧化碳和甲烷的浓度和同位素组成，与其他测量一起，将可以确定空气/水气体交换。 该奖项将使 PI 能够利用机会参加 2016 年夏季叶尼塞河 2000 公里河段的巡游活动。