CAREER: From the forest to the stream: Exploring forest land cover controls on dissolved organic matter character and aquatic ecosystem respiration in headwater streams

职业：从森林到溪流：探索森林土地覆盖对源头溪流中溶解有机物特征和水生生态系统呼吸的控制

• 批准号: 1945504
• 负责人: Tim Covino
• 金额: $ 83.31万
• 依托单位: Colorado 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: 2020-05-01 至 2023-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1945504&HistoricalAwards=false
• 关键词: CAREER; forest; stream; Exploring; land

Although inland waters comprise only ~1% of Earth’s surface, they play a central role in the global carbon cycle. Large amounts of carbon are delivered to inland waters as terrestrial dissolved organic matter (DOM) in headwater streams. The type and amount of DOM in these streams controls whether that carbon is released to the atmosphere (i.e. stream respiration) or removed from the carbon cycle (i.e. transported downstream and buried). This project will determine the role of forest harvesting, and specifically clear cutting, in controlling carbon cycling and stream respiration in headwater streams. The results from this project will be used to develop predictive models that guide future research and inform management of forested headwater systems. This project will provide training for at least 2 PhD and 9 undergraduate student researchers who will gain interdisciplinary expertise in the hydrologic and biogeochemical sciences, solving problems of societal concern. Data and understanding gained in this project will be used as university class examples to discuss the linkages between land management, carbon cycling, and hydrologic response of forested ecosystems. This project will develop educational materials on watershed science that will reach nearly 6,000 K-12 students, 48 science teachers, and 40 pre-service students to enhance understanding of land cover-ecosystem interactions and knowledge of their local watersheds.Inland waters have recently been highlighted for their importance in global carbon pools and fluxes relative to terrestrial and marine systems. Dissolved organic matter (DOM) represents the largest fraction of organic carbon transported through stream networks, and much of this DOM enters streams in headwater forest locations. This project answers the call to ‘focus on better identifying human impacts on the transport and biogeochemical cycling of carbon by inland waters’ as outlined in the Second State of the Carbon Cycle Report, by: 1) Determining the role of forest harvesting in regulating DOM character in headwater streams; 2) Quantifying the influence of DOM character on stream ecosystem respiration; and 3) Identifying how components 1 and 2 interact to regulate spatial and temporal patterns of ecosystem respiration across forested headwater stream networks. This information will be used to create predictions that will then be confronted with data to improve models, and expose gaps in understanding to guide future field and lab experimentation. This project will develop a vertically integrated program of mentorship, education, and provide training for undergraduate and PhD students who will gain exposure to research, outreach, and professional development activities. Through collaboration with the College of Natural Science Education and Outreach Center, this project will develop a STEM kit on watershed science specifically targeted at K-12 schools with a high percentage of underrepresented students, and encourage these groups to pursue STEM pathways.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.

尽管内陆水域仅占地球表面的 1%，但它们在全球碳循环中发挥着核心作用，大量碳以源头河流中的陆地溶解有机物 (DOM) 的形式输送到内陆水域。这些溪流中的碳控制着碳是否释放到大气中（即溪流呼吸）或从碳循环中去除（即向下游运输和掩埋）。该项目将确定森林采伐，特别是砍伐在控制中的作用。该项目的结果将用于开发预测模型，指导未来的研究并为森林水源系统的管理提供信息。该项目将为至少 2 名博士生和 9 名本科生研究人员提供培训。获得水文和生物地球化学科学的跨学科专业知识，解决社会关注的问题。在该项目中获得的数据和理解将用作大学课堂示例，讨论土地管理、碳循环和森林生态系统水文响应之间的联系。将开发流域科学教育材料，供近 6,000 名 K-12 学生、48 名科学教师和 40 名职前学生使用，以增强对土地覆盖-生态系统相互作用的理解以及对当地流域的了解。溶解有机物 (DOM) 因其在全球碳库和相对于陆地和海洋系统的通量中的重要性而受到关注，它代表了通过河流网络传输的有机碳的最大部分，并且大部分 DOM 进入河流。该项目响应了《第二份碳循环状况报告》中“更好地确定人类对内陆水域碳运输和生物地球化学循环的影响”的号召，具体措施如下： 1) 确定森林的作用采集在调节源头溪流中 DOM 特征中的作用；2) 量化 DOM 特征对溪流生态系统呼吸的影响；以及 3) 确定成分 1 和 2 如何相互作用来调节森林生态系统呼吸的空间和时间模式这些信息将用于创建预测，然后用数据来改进模型，并揭示理解上的差距，以指导未来的现场和实验室实验。该项目将开发一个垂直整合的指导、教育和实验计划。通过与自然科学学院教育和外展中心合作，该项目将为本科生和博士生提供接触研究、外展和专业发展活动的培训，专门针对 K-12 学生开发分水岭科学 STEM 套件。比例较高的学校该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Amount and reactivity of dissolved organic matter export are affected by land cover change from old‐growth to second‐growth forests in headwater ecosystems

溶解性有机物输出量和反应性受到水源生态系统中从老林到次生林土地覆盖变化的影响

• DOI: 10.1002/hyp.14343
• 发表时间: 2021
• 期刊: Hydrological Processes
• 影响因子: 3.2
• 作者: Fegel, Timothy S.;Boot, Claudia M.;Covino, Timothy P.;Elder, Kelly;Hall, Edward K.;Starr, Banning;Stegen, James;Rhoades, Charles C.
• 通讯作者: Rhoades, Charles C.

Conservative solute transport processes and associated transient storage mechanisms: Comparing streams with contrasting channel morphologies, land use and land cover

保守的溶质传输过程和相关的瞬时存储机制：比较具有对比河道形态、土地利用和土地覆盖的河流

• DOI: 10.1002/hyp.14564
• 发表时间: 2022
• 期刊: Hydrological Processes
• 影响因子: 3.2
• 作者: Emanuelson, Karin;Covino, Tim;Ward, Adam S.;Dorley, Jancoba;Gooseff, Michael
• 通讯作者: Gooseff, Michael