CAREER: Unlocking Recalcitrant Carbon to Enhance Denitrification of Nonpoint Source Nitrogen in Woodchip Bioreactors

职业：释放顽固碳以增强木片生物反应器中非点源氮的反硝化

• 批准号: 2237947
• 负责人: Matthew Reid
• 金额: $ 54.62万
• 依托单位: Cornell University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2028-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2237947&HistoricalAwards=false
• 关键词: CAREER; Unlocking; Recalcitrant; Carbon; Enhance

Nonpoint sources of nitrogen (N) such as nitrate from agricultural and stormwater runoff are among the most intractable drivers of pollution and water quality impairments in the United States, contributing to eutrophication, harmful algal blooms, and hypoxia, which adversely impact the ecological health, economic, and recreational values of the Nation’s surface water systems including lakes, rivers, and large estuaries such as the Chesapeake Bay and the Gulf of Mexico. Woodchip bioreactors (WBRs) have emerged as promising and scalable biofiltration systems for removing nitrate from agricultural and stormwater runoff. Most WBRs consist of subsurface trenches filled with a carbon source (woodchip) designed to stimulate microbial denitrification (DN) to remove nitrate from a flowing runoff stream prior to its discharge into a receiving surface water system. The effectiveness of current WBRs is limited by the slow release of the bioavailable carbon (C) from the woodchip media required to support the growth and metabolism of DN bacteria. The overarching goal of this CAREER project is to probe, elucidate, and leverage the redox biogeochemical reactions that control the release and mobilization of bioavailable C from woodchip media to stimulate DN in WBRs. To advance this goal, the Principal Investigator proposes to test the hypothesis that oxic-anoxic cycling during the operation of a woodchip bioreactor enhances denitrification by accelerating the decomposition of recalcitrant, lignocellulosic woodchip biomass into labile C during oxic periods to stimulate the growth and metabolic activity of DN microorganisms during subsequent anoxic periods. The successful completion of this project will benefit society through the generation of new fundamental knowledge to support the development and deployment of more efficient and sustainable solutions to manage and mitigate nonpoint sources of nitrate pollution. Additional benefits to society will be achieved through student education and training including the mentoring of a graduate student at Cornell University. Biogeochemical reactions of iron (Fe) and manganese (Mn) minerals at redox interfaces play an important role in the decomposition of lignocellulosic biomass (LB) in the environment, and mechanistic understanding of these organo-mineral interactions is rapidly evolving. This CAREER project will investigate and unravel the redox active biogeochemical reactions that control the release of labile carbon (C) from the degradation of woodchip media with the goal of leveraging this new knowledge to improve the performance of woodchip bioreactors (WBRs) that utilize LB as C source to stimulate the growth of denitrifying (DN) microorganisms to remove nitrate from agricultural and stormwater runoff. The specific objectives of the research are to 1) probe and elucidate Mn- and Fe- driven redox reactions that control the release of dissolved organic carbon (DOC) from woodchip media in model WBRs using state-of-the-art characterization techniques including synchrotron-based spectroscopy and microscopy (e.g., micro-XANES and micro-XRF) and advanced mass spectrometry (e.g., FT-ICR MS); 2) assess and evaluate the effects of enzymatic vs. nonenzymatic transformations on the quantity and quality of DOC released from woodchip media in model WBRs; and 3) develop and validate process-based models to simulate the effects of redox fluctuations and cycling on the release of DOC and DN efficiency in flow-through WBRs. The successful completion of this project has the potential for transformative impact through the generation of new fundamental knowledge to advance the design and implementation of more efficient WBRs for the removal of nitrate from agricultural and stormwater runoff. To implement the educational and outreach activities of this CAREER project, the Principal Investigator (PI) proposes to leverage existing programs and resources at Cornell University to develop and deliver new hands-on experiential learning opportunities in environmental engineering (EE) for students from underrepresented groups. The proposed activities will include i) an outreach program to high school students and teachers from rural areas of Central New York State and ii) a summer training and mentorship program for undergraduate and community college students. In addition, the PI proposes to leverage the project resources and research findings to develop and integrate new course modules on sensing and control of water infrastructure systems for nitrogen pollution removal into the EE undergraduate curriculum at Cornell University.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.

氮（N）的非点来源，例如农业和雨水径流中的硝酸盐，是美国最棘手的污染和水质影响驱动因素之一，有助于富营养化，有害的藻类血液和缺氧，不利地影响了国家的经济健康和娱乐性饮水剂，以及Lakes的巨大娱乐活动。切萨皮克湾和墨西哥湾。 Woodchip生物反应器（WBR）已经出现，如有承诺，可扩展的生物过滤系统，可从农业和雨水径流中去除硝酸盐。大多数WBR由填充的地下沟渠组成，旨在刺激微生物非硝化（DN），以从流动的径流流中去除硝酸盐，然后再将其排放到接收地表水系统中。当前WBR的有效性受生物利用碳（C）缓慢释放的限制，以支持DN细菌的生长和代谢所需的木质培养基。该职业项目的总体目标是探究，阐明和利用氧化还原生物地球化学反应，以控制Woodchip媒体的生物可用性C的释放和动员，以刺激WBR中的DN。为了促进这一目标，首席研究者提出的提议要测试以下假说：木chip生物反应器过程中的氧气 - 氧化循环通过加速恢复，木质纤维纤维素chip木质木质木质木质木质木材的分解，从而增强非硝化，从而在氧化和Mickabolic and controox anctip of dn Mickrocortion中刺激dn sickity nigabolics controsist。该项目的成功完成将通过产生新的基本知识来使社会受益，以支持开发和部署更高效，更可持续的解决方案，以管理和减轻硝酸盐污染的非点来源。通过学生的教育和培训，包括康奈尔大学的研究生的心理，可以通过学生的教育和培训来实现其他好处。氧化还原界面的铁（Fe）和锰（MN）矿物质的生物地球化学反应在环境中在木质纤维素生物量（LB）的分解中起着重要作用，并且对这些有机矿物相互作用的机械理解迅速发展。该职业项目将调查并揭示氧化还原主动的生物地球化学反应，从而控制不稳定的碳（C）从木奇普媒体退化中释放的释放，目的是利用这一新知识来提高木奇生物反应器（WBRS）的性能，以利用LB作为C源来刺激dnitrify and dnitrifering（dns）的成长（dns dns），从径流。研究的具体目的是1）使用最先进的特征技术在WOWCHIP媒体中释放溶解的有机碳（DOC）的探测和探测和FE驱动的氧化还原反应，该反应使用最先进的特征技术在模型WBR中释放了溶解的有机碳（DOC）。 多发性硬化症）; 2）评估和评估酶促与非酶转化对模型WBR中Woodchip媒体发行的DOC的数量和质量的影响； 3）开发和验证基于过程的模型，以模拟氧化还原波动和循环对流通WBR中DOC和DN效率的释放的影响。该项目的成功完成，通过产生新的基本知识，可以推进更有效的WBR的设计和实施，从而从农业和雨水径流中取出硝酸盐，从而产生变革性的影响。为了实施该职业项目的教育和外展活动，首席研究员（PI）的建议旨在利用康奈尔大学的现有计划和资源来开发和提供新的动手实践经验丰富的环境工程学习机会（EE），以供来自代表性不足的群体的学生提供。拟议的活动将包括i）纽约州中部农村地区和II）的高中生和老师的外展计划，以及针对本科和社区大学生的夏季培训和心理计划。 In addition, the PI proposals to leverage the project resources and research findings to develop and integrate new course modules on sensitivity and control of water infrastructure systems for nitrogen pollution removal into the EE undergraduate curriculum at Cornell University.This award reflects NSF's statutory mission and has been deemed precious of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.