RAPID: Using a drought-enhanced nitrate pulse to understand stream N retention and processing

RAPID：使用干旱增强的硝酸盐脉冲来了解河流氮的保留和处理

• 批准号: 1263559
• 负责人: Amy Burgin
• 金额: $ 19.76万
• 依托单位: University of Nebraska-Lincoln
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-11-01 至 2014-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1263559&HistoricalAwards=false
• 关键词: RAPID; Using; drought; enhanced; nitrate

Nitrogen addition is a cornerstone of modern agriculture, but fertilization has impacted inland and coastal waters by increasing nitrogen concentrations, supporting excessive growth of aquatic plants, reducing oxygen concentrations, and triggering harmful algal blooms. Because of extreme drought in 2012, Midwestern soils have accumulated nitrogen that is expected to be driven into river networks by late summer or fall precipitation. This anticipated landscape-wide nitrogen pulse offers an immediate and unparalleled opportunity to record how nitrogen enters streams, and to quantify the transport, attenuation, and fate of nitrogen as it moves through stream networks. An existing stream monitoring network will be expanded and used to collect water samples during and after major precipitation events in fall 2012, taking advantage of a short-term opportunity to characterize nitrogen movement and processing in an agricultural landscape.Unintended consequences of fertilization are an increasingly important issue for resource managers. This project will add to our understanding of how nitrogen moves from agricultural lands into and through stream networks, and it will do so under climate conditions that are expected to be more common in the coming decades. Additionally, this project will support five early career scientists and a collaboration between the University of Nebraska-Lincoln, the University of Iowa, and Coe College. Inclusion of Coe College will provide opportunities for undergraduate research and mentoring of undergraduate students by faculty and graduate students.

氮素添加是现代农业的基石，但施肥增加了氮素浓度，支持了水生植物的过度生长，降低了氧气浓度，并引发了有害的藻类水华，从而影响了内陆和沿海水域。由于2012年的极端干旱，中西部土壤积累了氮素，预计这些氮素将被夏末或秋季降水带入河网。这一预期的全景氮素脉冲提供了一个即时和无与伦比的机会来记录氮素如何进入河流，并量化氮素在河流网络中的传输、衰减和去向。现有的河流监测网络将扩大并用于在2012年秋季主要降水事件期间和之后收集水样，利用一个短期机会来描述农业景观中的氮素移动和加工。对资源管理者来说，施肥的意外后果是一个越来越重要的问题。这个项目将增加我们对氮如何从农田进入和通过河流网络的理解，它将在预计在未来几十年更加常见的气候条件下做到这一点。此外，该项目将支持五名早期职业科学家，以及内布拉斯加-林肯大学、爱荷华大学和科学院之间的合作。纳入COE学院将为本科生研究提供机会，并由教职员工和研究生指导本科生。