Integrated water management systems for sustainable use of agricultural lands and water

扩大集约农业生产需要使用足够的灌溉、排水和农用化学品。高施肥量的后果是增加了通过质量不佳的排水回流污染小溪、河流和湖泊的潜力。在马尼托巴省南部，灌溉马铃薯的产量正在扩大，这些地区劣质地下水造成的盐碱化一直是一个主要问题。通过设计良好的灌溉和排水系统进行适当的水管理可以最大限度地减少盐碱化问题。缓解盐碱化的策略之一是使用多余的灌溉水来清洗根部以下的盐分，并通过排水系统清除这些多余的水。如果排水回流被引导到工程湿地，污染物可以被植被去除。这将允许在干旱时期将水重新用于灌溉，从而消除对河流和湖泊的污染。 将调查排水/次灌溉系统的运行情况，将排水回流引导到设计适当的工程湿地，并评估水质的变化。拟议研究计划的长期目标是开发综合水管理系统，允许扩大集约化高价值作物生产，同时保护土地和水免受污染。 田间试验采用带状小区设计，分别采用顶灌排水、渗灌/排水、顶灌不排水、不灌不排水处理。土壤根区将全面安装仪器，监测水分和盐分的运动。排水回流将被引导到不同的工程湿地，那里的盐分和养分将被不同类型的盐生植物吸收，这些植物可以生长在盐碱环境中。定期采集生物量以去除工程湿地的盐分负荷，以确定不同盐生植物的盐分去除效率。这些试验的结果将使灌溉/排水更可持续。

The expansion of intensive agricultural production requires the use of adequate irrigation, drainage, and agricultural chemicals. The consequence of high fertilizer application is the increased potential to pollute the streams, rivers, and lakes via poor quality drainage return flows. Irrigated potato production is expanding in Southern Manitoba in areas where salinization from poor quality groundwater has been a major problem. Proper water management through well-designed irrigation and drainage systems can minimize the salinization problems. One of the strategies to mitigate salinization is to use excess irrigation water to wash the salts below the root zone and remove this excess water by a drainage system. If the drainage return flows are directed to engineered-wetlands, the pollutants could be removed by vegetation. This will allow the water to be re-used for irrigation during dry periods and thus eliminate the pollution of rivers and lakes. The operation of drainage/subirrigation system will be investigated and the drainage return flow will be directed to properly designed engineered-wetlands and the changes in water quality will be assessed. The long term objective of the proposed research program is to develop integrated water management systems that will allow expansion of intensive high-value crop production while protecting the land and water from pollution. Field experiments will be conducted in a strip-plot design with overhead irrigation with drainage, subirrigation/drainage, overhead irrigation without drainage, and no irrigation and no drainage as treatments. The soil root zone will be fully instrumented to monitor the water and salt movement. The drainage return flows will be directed into different engineered-wetlands where the salts and nutrients will be taken up by different types of halophytic plants that can grow in saline environments. Biomass will be periodically harvested to remove the salt load from the engineered-wetlands to determine the salt removal efficiency of different halophytic plants. The results from these experiments will make irrigation/drainage more sustainable.