CAREER: Nitrogen exchange and removal in riparian wetlands - the role of vegetation

职业：河岸湿地的氮交换和去除——植被的作用

• 批准号: 2339873
• 负责人: Amy Hansen
• 金额: $ 57.74万
• 依托单位: University of Kansas Center for Research Inc
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-04-01 至 2029-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2339873&HistoricalAwards=false
• 关键词: CAREER; Nitrogen; exchange; removal; riparian; CAREER; Nitrogen; exchange; removal; riparian

Excessive biologically available nitrogen has severely degraded water quality in streams and rivers of the agriculturally managed midwestern United States. Most nitrogen loading in this region occurs during high streamflow, flooded conditions when rivers are hydrologically connected to riparian wetlands. Despite clear evidence of wetland nitrogen removal, a mechanistic understanding of removal efficiency is lacking. Using a combination of field experiments, in situ and remote sensing observations, this project investigates how wetland vegetation regulates the interplay between water transport and nitrogen removal rates in physically and biologically distinct regions of riparian wetlands. This knowledge is required to harness the potential of wetlands to mitigate surface water quality degradation. In addition, a central challenge in managing water quality is the reliance on voluntary adoption of conservation actions to reduce nitrogen inputs. The education and outreach components of this project will provide opportunities to share science relevant to water quality stewardship with community members in an engaging setting and format. Overall, this project responds to a scientific and societal demand to generalize our understanding of wetlands system performance and identifies pathways to address impaired water quality under the expanding local, national and global footprint of agriculture.The overarching goal of this proposal is to advance scientific and student understanding of the role of riparian wetland vegetation in facilitating nitrogen removal during high streamflow, flooded conditions when most reactive nitrogen loading occurs. Specifically, this project will investigate the effect of riparian wetland vegetation distribution and structure on nitrogen removal at two spatial scales. At the reach scale, observational data along the study reach will quantify wetland inundation depth and extent, hydraulic exchange rate with the channel, vegetation structure and net nitrogen removal along the reach. At the vegetated canopy scale, field experiments will be used to measure nitrogen transformation and removal rates as a function of flow rate and in-canopy vegetation structure. Net nitrogen removal rates at canopy and reach scales will be compared via a modeling approach to determine whether local-scale interactions can explain net patterns in nitrogen removal. This project additionally seeks to promote water quality stewardship through an experiential, communication focused educational initiative and student led outreach activities while increasing student diversity. Educational activities will be structured to first build university student expertise via active learning in courses then have the students teach what they have learned through a local science center and its successful existing outreach program.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.

过多的生物学上可用的氮在美国中西部管理的农业管理的溪流和河流中严重退化了水质。该区域中的大多数氮负荷发生在高流量期间，当河流与河岸湿地连接时，洪水泛滥。尽管有明确的湿地氮去除证据，但仍缺乏对去除效率的机械理解。该项目结合了现场实验，原位和遥感观测，研究了湿地植被如何调节河岸湿地的物理和生物学上不同区域的水转运与氮去除率之间的相互作用。需要这种知识来利用湿地减轻地表水质降解的潜力。此外，管理水质的核心挑战是依赖自愿采用保护措施以减少氮输入。该项目的教育和外展成分将为与社区成员分享与水质管理有关的科学的机会，以吸引人的环境和格式。总体而言，该项目对科学和社会的需求做出了反应，以概括我们对湿地系统表现的理解，并确定在不断扩大的农业足迹下，解决湿地系统的表现，以解决水质受损。该提案的总体目标是提高科学和学生对河岸湿地在促进nit型中的影响时对河岸湿地的作用的理解。具体而言，该项目将研究河岸湿地植被分布和结构对两个空间尺度上氮去除的影响。在触及量表上，沿研究范围的观察数据将量化湿地淹没深度和范围，液压汇率，通道，植被结构和沿触及范围的净氮去除。在植被冠层尺度上，将使用现场实验来测量氮的转化和去除速率，这是流速和自动物内植被结构的函数。将通过建模方法比较冠层的净氮去除速率，以确定局部规模的相互作用是否可以解释去除氮的净模式。该项目还旨在通过以体验，以沟通为主教的教育计划和学生领导的外展活动来促进水质管理，同时增加了学生的多样性。教育活动将结构结构化，首先通过积极学习在课程中建立大学生专业知识，然后让学生通过当地的科学中心及其成功的现有外展计划来教授他们所学到的知识。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛影响的审查标准来通过评估来获得支持的。