Runoff generation and phosphorus mobilization in agricultural landscapes

农业景观中径流的产生和磷的动员

• 批准号: RGPIN-2015-04816
• 负责人: Macrae, Merrin
• 金额: $ 1.6万
• 依托单位: University of Waterloo
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=613186
• 关键词: Runoff; generation; phosphorus; mobilization; agricultural

Phosphorus (P) export from non-point sources in agriculture-dominated catchments is a global issue, and a priority area for many regions in Canada, where Harmful Algal Blooms (HABs) have been observed in large lakes with increasing frequency. Despite the implementation of Beneficial Management Practices (BMPs) to reduce P loss, P loads are not decreasing and in fact are increasing in some regions. Existing models for P export and management strategies largely target rainfall event-driven surface runoff and do not effectively address winter processes and the snowmelt period. This period represents a significant gap in our scientific understanding of P mobilization in agricultural regions. In many midlatitude regions globally, the winter period is the dominant annual flux for both runoff and P. Thus, an understanding of the drivers of P loss in winter and early spring is needed. The objective of this proposal, and the short-term objective of my research program is to improve scientific understanding of the impacts of winter conditions on P supply and transport processes, and how these interact to drive P transfer in surface and subsurface runoff. An improved scientific understanding of runoff generation and P mobilization dynamics in both surface and subsurface pathways in agricultural catchments is needed to develop and implement effective strategies that reduce P loads via both of these pathways. An understanding of the role of climate drivers on these processes will also provide insight into how agricultural systems may respond to climate change, if conditions shift from snow-dominated to more precipitation dominated with reduced soil frost as has been projected. Field investigations will be coupled with novel experiments done in the field and in the laboratory at the University of Waterloo, and four graduate students will be trained as part of this work. My proposed research will have significant environmental and economic impacts as it addresses issues related to climate (and climate change) and issues that are relevant to agricultural management (i.e. artificial drainage). Most importantly, this research targets the winter period, and is based on observational field data, and therefore addresses a significant knowledge gap.

以农业为主的流域非点源磷（P）出口是一个全球性问题，也是加拿大许多地区的优先领域，尽管实施了这些措施，但在这些地区大型湖泊中发现有害藻华（HAB）的现象越来越频繁。为减少磷损失而实施的有益管理实践（BMP），磷负荷并未减少，事实上，在一些地区，现有的磷输出和管理策略模型主要针对降雨事件驱动的地表径流，而不是减少。有效地解决冬季过程和融雪期。这一时期代表了我们对农业地区磷动员的科学认识上的重大差距。在全球许多中纬度地区，冬季是径流和磷的主要年度通量。需要了解冬季和早春磷流失的驱动因素。 该提案的目标以及我的研究计划的短期目标是提高对冬季条件对磷供应和运输过程的影响的科学理解，以及它们如何相互作用以驱动地表和地下径流中的磷转移。需要对农业流域地表和地下途径的径流生成和磷动员动态进行科学了解，以制定和实施通过这两种途径减少磷负荷的有效策略。了解气候驱动因素在这些过程中的作用也将提供帮助。深入了解农业系统如何应对气候如果情况如预测的那样从降雪为主转变为以降水为主且土壤霜减少，就会发生变化。 现场调查将与滑铁卢大学现场和实验室进行的新颖实验相结合，作为这项工作的一部分，四名研究生将接受培训，因为它解决了相关问题，将产生重大的环境和经济影响。最重要的是，这项研究针对的是冬季，并且基于实地观测数据，因此解决了重大的知识差距。