Mechanics and Modelling of Agricultural Nonpoint Source Pollution

长期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，包括基于流域的水源保护和养分管理。这种方法的发展；粮食安全、环境可持续性、土壤复原力、可持续粮食生产和未来能力建设所需；将提供评估结构和非结构最佳管理以及水管理做法对流域内水体健康的影响的手段。发展这种方法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养分负荷采用的最佳管理做法。本研究的重点是量化由于气候变化导致的河流流量状况的变化，开发一种易于使用的筛选方法，用于应用非点源污染最佳管理实践，以及开发一种创新的方法来评估采用结构和非结构最佳管理实践的性能，以控制和改善安大略省独特的季节性气候条件下的河流水质。这种方法将导致开发有效管理由于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。拟议的目标将通过以下方式实现：(i)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；（ii）发展一种易于使用的筛选方法，以确定沉积物和磷源的位置，以便在流域应用最佳管理做法；（iii）开发基于事件的流域模型，该模型能够明确评估季节性降雨事件和结构最佳管理实践（如管道入口和盲入口）的影响，以及非结构最佳管理实践（如在流域内和沿溪流采用非点源污染控制的植物过滤带）的影响。这项研究将提供一种工具来评估道路边的沟渠和可变的田地边界对输送到河流的沉积物和营养物质的影响。这项研究还将提供一种简单的筛选工具，以确定在农业流域应用最佳管理做法的地点。虽然这项研究的重点是安大略省的情况，但其结果将适用于该国其他地区。最终的受益者将是社会和人类，他们将从潜在的水源保护和水质改善中受益。

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.