Kamrath Brock, Yuan Yongping
Office of Research and Development, United States Environmental Protection Agency, Research Triangle Park, North Carolina, USA.
Trans ASABE. 2023;1(2):77-88. doi: 10.13031/jnrae.15572.
Dissolved reactive phosphorus (DRP) export from agricultural areas is a leading cause of nutrient pollution in freshwater systems (e.g., the North American Great Lakes). A potential solution to mitigate the excessive release of DRP is the use of nutrient management. To evaluate the effectiveness of nutrient management for phosphorus (P) in the United States, we conducted a review to synthesize P management and DRP export data from peer-reviewed articles published between 2000 to 2022. We identified 15 publications and extracted 113 and 90 observations from plot- and field-scale studies, respectively. At the plot scale, mean DRP concentrations were approximately 60% lower when P application rates were below the maximum recommended rate. In addition to the lower mean value, more extreme DRP export events occurred when the P fertilization rate was greater than the maximum recommended rate. In terms of application method, subsurface placement reduced mean DRP concentrations during rainfall simulations by 88% relative to surface placement (i.e., broadcasting). For fertilizer sources, mean DRP concentrations were similar between inorganic and organic fertilizers. However, at high application rates, organic fertilizers had a greater potential to produce extreme DRP export events. At the field-scale, organic fertilizers applied at high rates had the potential to produce extreme DRP export events. However, field-scale results for the other nutrient management techniques were generally inconclusive due to a limited number of studies and confounding factors. Overall, these results displayed the potential adverse impacts of overfertilization and the surface application of P fertilizers and highlighted the need for further research into the influence of nutrient management on P losses.
农业区域溶解态活性磷（DRP）的输出是淡水系统（如北美五大湖）营养物污染的主要原因。减轻DRP过量释放的一个潜在解决方案是采用养分管理。为评估美国磷（P）养分管理的有效性，我们进行了一项综述，以综合2000年至2022年发表的同行评审文章中的磷管理和DRP输出数据。我们确定了15篇出版物，并分别从小区尺度和田间尺度研究中提取了113个和90个观测数据。在小区尺度上，当磷肥施用量低于最大推荐量时，平均DRP浓度大约低60%。除了较低的平均值外，当施肥率大于最大推荐率时，会发生更极端的DRP输出事件。就施用方法而言，与地表施用（即撒播）相比，在降雨模拟期间，地下施肥使平均DRP浓度降低了88%。对于肥料来源，无机肥料和有机肥料的平均DRP浓度相似。然而，在高施用量下，有机肥料产生极端DRP输出事件的可能性更大。在田间尺度上，高施用量的有机肥料有可能产生极端DRP输出事件。然而，由于研究数量有限和混杂因素，其他养分管理技术的田间尺度结果通常尚无定论。总体而言，这些结果显示了过度施肥和磷肥地表施用的潜在不利影响，并强调需要进一步研究养分管理对磷流失的影响。
