CAREER: Quantifying the Extent and Biogeochemical Impact of Modern Ferruginous Lakes

职业：量化现代含铁湖泊的范围和生物地球化学影响

• 批准号: 1944946
• 负责人: Elizabeth Swanner
• 金额: $ 66.25万
• 依托单位: Iowa State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-07-01 至 2025-06-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1944946&HistoricalAwards=false
• 关键词: CAREER; Quantifying; Extent; Biogeochemical; Impact

Many small, deep lakes formed during the melting of continental ice sheets that covered much of the northern hemisphere before 10,000 years ago. It is hard for oxygen to mix into small, deep lakes, which makes them “microbial worlds”, as most aquatic animals can’t live without oxygen. This project will test whether such small lakes that lack oxygen also contain abundant iron, and whether that iron is supplied from the surrounding glacial deposits. With no oxygen, and abundant iron, lake microbes can produce methane out of sinking algal or plant material. Road salt applications near lakes might also cause lakes that did mix to stop mixing, making conditions better for methane-producing microbes. This work will give a better idea how lake shape, microbes, and water chemistry contribute to lake emissions of methane, which is an important but not well-understood contributor to natural greenhouse gas emissions to the atmosphere. The chemistry of these lakes is also similar to the oceans before 500 million years ago, before animals appeared, and so we can use them to help understand if oceans were producing methane in the past. Undergraduate and graduate students will collect field data from lakes in a rural and urban area in Minnesota (MN) as part of class and research expeditions. The field methods, findings, and data will be shared through traditional (publications and conferences) and non-traditional (YouTube videos, Wikipedia pages) outlets. Workshops in Minneapolis, MN will engage diverse youth, including residents of a historically African American neighborhood adjacent to an urban study lake. Workshops in Itasca State Park, MN, the site of the rural lakes, will engage the visiting public and residents of surrounding counties and nearby Native American population centers.There are only 22 ferruginous meromictic lakes worldwide identified in the literature, but do more exist? Most of the recognized ferruginous meromictic lakes are postglacial, with groundwater or peatlands a hypothesized, but unverified source of iron. More than a dozen postglacial lakes in two field areas in Minnesota (MN) will be evaluated for meromixis and ferruginous conditions, giving insight into how land use changes enhance meromixis. Detailed iron budgets will be constructed for two lakes to identify and quantify iron sources. Many ferruginous meromictic lakes have a subsurface chlorophyll a maximum layer at the iron-oxygen redoxcline, and the contribution of this layer to primary productivity and oxygen production will be quantified in two lakes. Furthermore, rates of methanogenesis, methane fluxes, and the contribution of methane to the organic carbon degradation will be quantified in two lakes to better constrain carbon fluxes under ferruginous conditions. The results of these activities will better delineate 1) the extent of meromictic ferruginous lakes, 2) fluxes of water and elements between surface and groundwater reservoirs, 3) and carbon cycling under ferruginous conditions, which predominated in Earth's past oceans and influenced the oxidation of Earth's surface.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.

在融化的连续冰盖融化过程中，许多小的深湖覆盖了10，000年前的大部分北半球。氧气很难混合成小的深湖，这使其成为“微生物世界”，因为大多数水生动物都无法没有氧气。该项目将测试缺少氧气的如此小的湖泊是否还含有丰富的铁，以及该铁是否是从周围冰川沉积物中提供的。没有氧气和丰富的铁，微生物可以从下沉的藻类或植物材料中产生甲烷。湖泊附近的道路盐应用也可能导致湖泊确实混合在一起混合，从而使产生甲烷的微生物更好。这项工作将有一个更好的了解，湖泊形状，微生物和水化学如何促进甲烷的湖泊排放，这是对天然温室气体排放到大气的重要但并不理解的贡献者。在5亿年前，在动物出现之前，这些湖泊的化学反应也与海洋相似，因此我们可以使用它们来帮助了解过去的海洋是否在过去产生甲烷。本科生和研究生将从明尼苏达州（明尼苏达州）（MN）的湖泊中收集现场数据，作为课堂和研究探险的一部分。现场方法，调查结果和数据将通过传统（出版物和会议）和非传统（YouTube视频，Wikipedia页面）插座共享。明尼苏达州明尼阿波利斯市的研讨会将吸引潜水者青年，其中包括与城市研究湖相邻的历史悠久的非裔美国人社区的居民。在明尼苏达州ITASCA州立公园的研讨会是粗糙湖泊的遗址，将与周边县和附近的美国原住民中心的来访公众和居民接触。在文献中，全球只有22个铁质的湖泊湖泊，但还有更多吗？大多数公认的铁虫湖泊是冰川后的，地下水或皮兰德是假设的，但没有验证的铁来源。明尼苏达州两个现场（MN）的冰河后湖泊将用于Meromixis和Fererruginous条件，从而深入了解土地利用变化如何增强Meromixis。将建造详细的铁预算，供两个湖泊识别和量化铁源。许多铁质的meromic湖泊在铁氧氧化还能环林处具有最大层面的地下叶绿素，并且该层对初级生产和氧气产生的贡献将在两个湖泊中进行量化。此外，将在两个湖泊中量化甲烷发生，甲烷通量和甲烷对有机碳降解的贡献，以更好地限制铁质条件下的碳通量。这些活动的结果将更好地描述1）Meromic铁氧湖的程度，2）水和表面和地下水储量之间的磁通量和元素，3）和在铁质条件下的碳循环量，这些碳循环在地球过去的海洋中，这些海洋中的海洋中的海洋中充满了地球的氧化，并影响了NSF的氧化，并反映了NSF的氧化商标。更广泛的影响审查标准。

项目成果

Evaluation of preservation protocols for oxygen‐sensitive minerals within laminated aquatic sediments

层状水生沉积物中氧敏感矿物的保存方案评估

• DOI: 10.1002/lom3.10533
• 发表时间: 2023
• 期刊: Limnology and Oceanography: Methods
• 作者: Ledesma, Gabrielle;Islam, Raisa;Swanner, Elizabeth D.
• 通讯作者: Swanner, Elizabeth D.

Methane-derived authigenic carbonates – A case for a globally relevant marine carbonate factory

• DOI: 10.1016/j.earscirev.2023.104487
• 发表时间: 2023-08
• 期刊: Earth-Science Reviews
• 影响因子: 12.1
• 作者: Sajjad Akam;E. Swanner;H. Yao;W. Hong;Jörn Peckmann

Water properties of Arco Lake, Budd Lake, Deming Lake, and Josephine Lake in Itasca State Park from 2006-2009 and 2019-2021, v. 2.

2006-2009 年和 2019-2021 年艾塔斯卡州立公园阿科湖、巴德湖、戴明湖和约瑟芬湖的水特性，v. 2。

• DOI: 10.6073/pasta/692c92ef1c8291162732c2b98cebdaea
• 发表时间: 2022
• 期刊: Environmental Data Initiative
• 作者: Swanner, Elizabeth D;Lascu, Ioan;Ledesma, Gabrielle;Leung, Tania;Akam, Sajjad
• 通讯作者: Akam, Sajjad

Geochemical data from sediments and porewaters from ferruginous and meromictic Brownie Lake, Minnesota, U.S.A.

来自美国明尼苏达州铁质和半重质布朗尼湖沉积物和孔隙水的地球化学数据

• DOI: 10.6073/pasta/68b50baa0a767ab33f2b7dd91948036e
• 发表时间: 2022
• 期刊: Environmental Data Initiative
• 作者: Swanner, Elizabeth D.;Islam, Raisa;Ledesma, Gabrielle;Wittkop, Chad;Akam, Sajjad;Eitel, Eryn;Katsev, Sergei;Johnson, Ben;Poulton, Simon;Bray, Andy
• 通讯作者: Bray, Andy

Water properties of Brownie Lake, MN and Canyon Lake, MI from 2015-2019

2015-2019 年明尼苏达州布朗尼湖和密歇根州峡谷湖的水特性

• DOI: 10.6073/pasta/4eaf698b4efbaf793b83d95f464d1672
• 发表时间: 2021
• 期刊: Environmental Data Initiative
• 作者: Swanner, Elizabeth D;Lambrecht, Nicholas;Wittkop, Chad;Katsev, Sergei;Ledesma, Gabrielle;Leung, Tania
• 通讯作者: Leung, Tania