Spatial variability of soil nitrogen and phosphorus and assessment of nutrient use in rotation crops following pigs on an outdoor hog-rearing farm in Eastern Ontario

开发替代传统畜牧业的可持续发展方法是一个活跃的研究领域。大多数传统畜牧业都有某种形式的负面经济、环境或社会影响。因此，人们对发展重视动物福利和优化将牲畜田间安置纳入作物轮作系统的畜牧业系统越来越感兴趣。室外养猪作业通常与土壤中氮和磷的高水平不规则分布有关。了解这些养分在农田内的垂直和水平分布，对于制定作物轮作的管理决策至关重要。仔细选择猪周期后种植的作物或饲料对于最大限度地利用作物轮作系统中的养分也很重要。我们提出了一项研究，以评估氮和磷的空间分布后，一年轮作系统的猪在安大略省东南部的农场。我们将同时进行一项温室试验，以检验在猪轮作土壤中生长的饲料作物和混合饲料的产量、氮和磷吸收能力，并与对照土壤和商业肥料处理进行比较。我们的目标是：(1)通过量化土壤中氮和磷的数量和分布，最大限度地提高轮作系统中的养分利用效率；(2)在养猪轮作后，从养分更新和产量生产方面找到有效的作物，这将减少潜在的养分损失给环境的风险，并有助于农场盈利。

Developing sustainable alternatives to conventional livestock farming practices is an active area of research. Most conventional livestock farming practices have some form of negative economic, environmental or social impact. Consequently, there is an increased interest in developing livestock farming systems that value animal welfare and optimize the integration of livestock field placement into crop rotation systems. Outdoor swine-rearing operations are commonly associated with high levels of irregularly distributed nitrogen and phosphorus in soil. Understanding of the distribution of these nutrients, both vertically and horizontally within a farm plot, is crucial to making management decisions for crop rotations. Careful selection of crops or forages to be grown after a pig cycle is also important to maximize the use efficiency of nutrients within a crop rotation system. We propose a study to assess the spatial distribution of nitrogen and phosphorus after a year of pigs in a rotational system in a South-eastern Ontario farm. We will concurrently conduct a greenhouse experiment to examine the yield, N and P uptake ability of feed crops and forage mixtures grown in pig-rotation soil, as compared to control soil and commercial fertilizer treatments. Our goals are to (1) maximize the nutrient use efficiency in a rotational system by quantifying the amount and distribution of nitrogen and phosphorus in the soil, and (2) find efficient crops in terms of nutrient update and yield production to grow after a pig rotation, that will reduce potential risk of nutrient losses to the environment, and contribute to farm profitability.