Mechanics and Modelling of Agricultural Nonpoint Source Pollution

长期的研究目标是开发环境可持续的非点源污染控制的实用方法，包括基于分水岭的水源保护和养分管理。为粮食安全、环境可持续性、可持续粮食生产和未来能力建设的土壤复原力所需的这种方法的发展，将提供评估结构性和非结构性最佳管理和水管理做法对分水岭水体健康的影响的手段。这种方法的发展还需要更好地了解和描述影响季节性水文的水文变量和过程，它们对水流模式的影响，以及对营养物质负荷采取的最佳管理做法。这项研究的重点是量化气候变化引起的河流水流状况的变化，开发一种易于使用的筛选方法来应用非点源污染最佳管理实践，并开发一种创新的方法来评估在安大略省独特的季节性气候条件下控制和改善河流水质所采用的结构性和非结构性最佳管理实践的表现。这一办法将导致开发有效管理农业土地利用活动造成的沉积物和营养物非点源污染的工具。*将通过以下方式实现拟议目标：(1)量化气候变化对水文变量的影响，如季节性水流模式、温度和降水制度；(2)开发一种易于使用的筛选方法，以确定泥沙和磷源的位置，以便在流域内应用最佳管理做法；(3)开发一个基于事件的流域模型，能够明确评估季节性降雨事件和结构性最佳管理做法的影响，如管道口和盲水口等结构性最佳管理做法，以及用于非点源污染控制的非结构性最佳管理做法，如流域内和沿溪流植物滤带。这项研究将提供一种工具来评估路边沟渠和可变的场边界对向河流输送的泥沙和营养物质的影响。这项研究还将提供一个简单的筛选工具，以确定在农业分水岭中应用最佳管理做法的地点。虽然这项研究的重点一直是安大略省的条件，但结果将适用于该国的其他地区。最终的受益者将是社会和人类，他们将受益于潜在的水源保护和水质改善。

The long-term research goals have been to develop practical approaches for environmentally sustainable nonpoint source pollution control, including watershed based source water protection and nutrient management. Development of such approach; needed for food security, environmental sustainability, soil resilience for sustainable food production and for future capacity building; will provide means to assess the effect of structural and non-structural best management and water management practises on the health of the water bodies in a watershed. Development of such approaches also require better understanding and description of hydrologic variable and processes affecting seasonal hydrology, their impact of stream flow pattern and adopted best management practices on nutrient loads. This research focuses on the quantification of the changes in the stream flow regimes due to climate change, development of an easily use-able screening approach for the application of non-point source pollution best management practises, and the development of an innovative approach to evaluate the performance of structural and non-structural best management practises adopted to control and improve stream water quality in Ontario's unique seasonal climatic conditions. This approach will lead to the development of tools for effective management of sediment and nutrient non-point source pollution due to agricultural land use activities. *** The proposed goal will be achieved by (i) quantification of the effect of climate change on hydrologic variables such as seasonal stream flow pattern, temperature and precipitation regimes, (ii) by development of an easily usable screening approach to identify the location of sediment and phosphorus sources for application of best management practises in a watershed, and (iii) by development of an event based watershed model having the capability to explicitly evaluate the impact of seasonal rainfall events and structural best management practices such as pipe inlets and blind inlets, and non-structural best management practices such as within watershed and along the stream vegetative filter strips adopted for non-point source pollution control. This research will provide a tool to evaluate the impact of road side ditches and variable field boundaries on sediment and nutrients delivered to the stream. This research will also provide a simple screening tool to identify the location for the application of best management practises in an agricultural watershed. Though the focus of this research has been the Ontario conditions, the results will be applicable to other regions of the country. The ultimate beneficiary will be society and humanity, who will be benefited from potential source water protection and water quality improvements.