Phosphorus cycling in conservation cropping systems of the Canadian Prairies

加拿大大草原农业生产的可持续性要求施于土壤的养分有效地循环利用，而不是流失到环境中。 化肥也是农民的一项重要投入成本，提高化肥使用效率有助于提高经济效益。今天，大草原的种植制度正朝着少耕或免耕的方向发展，更多的土地也在施用动物粪便。 在加拿大大草原的免耕和施肥土壤中，磷的形态和转化不如氮的形态和转化有据可查。 生产者报告说，在这些种植系统中，对氮肥的需求减少，有些人现在报告说，对添加的磷的需求减少。据推测，通过有机组分的磷循环是更重要的，需要更好地理解，使适当的磷肥决策，在这些新的系统。这项研究将确定长期免耕和施肥土地中存在的重要磷库，以及控制磷周转和生物利用度的因素。

Sustainability of agricultural production on the Canadian prairies requires that the nutrients that are applied to soils are effectively recycled rather than lost to the environment.  Fertilizers also represent a significant input cost to farmers and greater efficiency in their use contributes to better economic returns. Cropping systems on the prairies today are moving towards reduced or zero-tillage, and more land is also receiving application of animal manures.  The forms and transformations of phosphorus in zero-till and manured soils of the Canadian prairies is not as well documented as for nitrogen.  Producers have reported less need for nitrogen fertilizer in these cropping systems and some are now reporting less requirement for added phosphorus. It is hypothesized that phosphorus cycling through organic fractions is more important and needs to be better understood to make appropriate P fertilization decisions in these new systems. The research will identify the important pools of phosphorus present in long-term no-till and manured lands, and the factors controlling phosphorus turnover and bioavailability.