Characterizing the release, dynamics and plant availability of phosphorus from recovered struvites

目前的作物品种如卡诺拉需要高的磷（P）用量以实现其高产潜力。由于其与土壤组分的相互作用，P在大多数农业土壤中具有非常低的流动性，这需要将其放置在根增殖区附近，即，在种子行，以提高吸收。然而，油菜对土壤溶液中中等高浓度的肥料养分敏感，结果是在种子行中放置高比例的可溶性磷肥会严重损害或杀死幼苗，从而降低产量。在加拿大大草原，一次将种子和所有肥料放置在种子行中是一种常见的做法;然而，对于油菜，大部分肥料必须放置在侧带或中间行带，以避免种子受损和幼苗死亡。磷的低流动性限制了带状施磷对植物根系发育的可及性。从我们的盆栽研究的初步结果表明，低溶解度，因此低盐指数鸟粪石可以允许（i）种子行放置高P率，而不会导致幼苗毒性和（ii）应用较低的P率，以产生相同的产量较高的传统磷肥。由于人们越来越重视补充不可再生资源（P）并尽量减少过量P损失对环境的不利环境影响，因此地表水体富营养化，不同形式的鸟粪石越来越多地变得可用。尽管最近有证据表明鸟粪石有益于作物生产，但控制鸟粪石磷在土壤中的有效性和植物吸收的过程和机制还不清楚。需要这些知识来制定优化作物产量和质量的战略，并最大限度地减少土壤中过量磷的积累，过量磷可以转移到地表水质量并导致富营养化。我的研究将采用实验室，温室，和现场技术来阐明控制植物的可用性和移动性的回收鸟粪石磷在不同的土壤，沿着与环境变量的动力学磷的可用性。研究结果将有助于提高可安全施用的剂量，以满足作物需求并优化产量，而不会对敏感作物（如油菜）产生幼苗毒性风险。除了有利于农民，因此加拿大的农业经济，并尽量减少磷的环境损失，从而保护加拿大的地表水资源，我的研究计划将培训HQP在广泛的研究技术，从建模磷的可用性，运输和命运的过程，以及国家的最先进的仪器技术表征磷的形式在土壤中，涉及利用建模和分析结果来提高作物田的产量。我的HQP将受益于与公共和私营部门合作者的互动。

Current cultivars of crops such as canola require high phosphorus (P) rates to realize their high yield potential. Because of its interaction with soil components, P has very low mobility in most agricultural soils, which necessitates its placement near the zone of root proliferation, i.e., in the seed row, to enhance uptake. However, canola is sensitive to moderately high concentrations of fertilizer nutrients in the soil solution, with the result that placement of high rates of soluble P fertilizers in the seed row can seriously damage or kill seedlings, thereby reducing yield. Placement of seed and all fertilizer in the seed row in one pass is a common practice on the Canadian Prairies; however, for canola, most of that fertilizer has to be placed in a side band or mid-row band to avoid seed damage and seedling mortality. The low mobility of P restricts the accessibility of band-applied P to developing plant roots. Preliminary results from our pot studies suggest that the low solubility, hence low salt index of struvite may allow (i) seed row placement of high P rates without causing seedling toxicity and (ii) application of lower P rates to produce the same yield as higher rates of conventional P fertilizers. Different forms of struvite are increasingly becoming available due to the growing emphasis on replenishing the non-renewable resource (P) and minimizing the adverse environmental impacts of excess P loss to the environment, hence eutrophication of surface water bodies. Despite recent evidence of struvite benefits in crop production, processes and mechanisms controlling struvite P availability in soils and uptake by plants are not well-understood. Such knowledge is needed to formulate strategies for optimizing crop yield and quality and minimizing the build up of excess P in soils, which can be transported to surface water quality and cause eutrophication. My research will employ laboratory, greenhouse, and field techniques to elucidate the processes controlling plant availability and mobility of recovered struvite P in different soils, along with the environmental variables governing the kinetics of P availability. Results will help increase the rates that can be safely applied to meet crop demand and optimize yields without risking seedling toxicity to sensitive crops such as canola. In addition to benefiting farmers, hence Canada's agroeconomy, and minimizing environmental loss of P, thereby protecting Canada's surface water resources, my research program will train HQP in a wide range of research techniques, from modeling P availability, transport and fate processes, as well as state-of-the-art instrumental techniques for characterizing P forms in the soil, to utilization of modeling and analytical results to improve yields in crop fields. My HQP will benefit from interaction with collaborators from the public and private sectors.