Influence of biosolid treatment on the presence and mobility of emerging organic contaminants in agricultural soils after land application

生物固体的土地应用将新出现的有机污染物(EOCs)引入土壤。虽然生物固体对土壤肥力有好处，但EOC含量受到污水处理过程的影响。生物固体处理如何影响EoC降解和流动性的机制还不完全清楚。我们以前已经证明，在农业生态系统中，集约化管理碱(石灰)稳定的生物固体会导致EOC的显著积累和潜在的水中迁移。了解生物固体处理如何推动EOC在土壤中的相互作用是这一5年计划的关键短期目标，以解决土壤健康风险这一更广泛的长期目标。推动短期目标的问题包括： 污水污泥处理如何影响最终生物固体产品中EOCs的存在？ 产生生物固体的过程是否影响EOCs在添加到土壤中后的生物降解速度？ 驱动EoC降解或迁移的机制是否与土壤的特性或生物固体的特性有关？ 实验室和实地研究将被用来检验生物固体处理对EOC-土壤相互作用有重大影响的假说。首先，我们将研究单一来源的原始污水污泥中的EOC浓度对三种稳定化技术的响应：堆肥、厌氧消化和石灰稳定化。这些生物固体将用于受控环境土壤培养和土柱迁移研究，以检验EOC的生物降解性和移动性。这些结果将与我们之前研究的两个污染物传输模型联系起来。将进行一项实地研究，以评估来自不同生物固体处理的EOCs在变温变湿条件下在土壤中以及与植物之间的反应。这些机理研究将加深对驱动EOC反应的潜在过程的理解，这些反应来自对土壤的生物固体处理。这项实地调查研究将在受管理的农业景观快速变化的条件下，将土壤中的这些动态联系起来。 拟议的工作是原创的，有能力在国内和国际上产生重大的直接影响。在加拿大和全球，城市环境中的废水固体浓度是一个迅速增长的问题。生物固体在农业系统中的扩散有能力每年引入数百吨人为化学品，我们对其影响的全部范围了解有限。我已经建立了重要的田野和实验室基础设施，以支持从陆地应用的生物固体中研究EOCs，我不知道在加拿大或国际上建立了许多类似的实验系统。这些研究将集中于我们对城市污水处理如何影响接受生物固体改良剂土壤中的EOC动态的理解。

Land application of biosolids introduces Emerging Organic Contaminants (EOCs) into the soil. While biosolids have benefits to soil fertility, EOC content is affected by sewage treatment processes. The mechanisms for how biosolids treatment affects EOC degradation and mobility are not fully understood. We have previously shown that intensive management of an alkaline (lime) stabilized biosolid in agro-ecosystems leads to significant EOC accumulation and potential transport into water. Understanding how biosolid treatment drives EOC interactions in soil is the key short-term objective for this 5-year program in order to address the broader long-term objective of what the risks are for soil health. The questions driving the short-term objectives are: How does sewage sludge treatment impact the presence of EOCs in the final biosolid product? Does the process of generating biosolids affect the rate at which EOCs will biodegrade after adding to soil? Are the mechanisms driving EOC degradation or mobility related to the properties of soil or the properties of the biosolid? Laboratory and field-based studies will be used to test the hypotheses that biosolid treatment has a significant impact on EOC-soil interactions. First, we will examine how EOC concentrations in a single source raw sewage sludge respond to three stabilization techniques: composting, anaerobic digestion, and lime stabilization. These biosolids will be used in controlled environment soil incubation and soil column transport studies to examine EOC biodegradation and mobility. These results will be linked to two contaminant transport models that we have previously worked on. A field study will be established to evaluate how EOCs from the different biosolid treatments respond in soils under conditions of variable temperature and moisture, as well as with plants. The mechanistic studies will develop an understanding of underlying processes driving the EOC responses from biosolid treatments amended to soils. The empirical field study will contextualize these dynamics in soils under the rapidly changing conditions of managed agricultural landscapes. The proposed work is original and has the capacity to have significant immediate impact nationally and internationally. Concentration of wastewater solids in urban environments is rapidly growing issue in Canada and globally. The dispersal of biosolids in agricultural systems has the capacity to introduce hundreds of tons annually of anthropogenic chemicals that we have limited understanding of the full scope of their impact. I have built significant field and laboratory infrastructure in support of studying EOCs from land applied biosolids and I not aware of many similar experimental systems established in Canada or internationally. These studies will focus our understanding of how municipal sewage treatment affects EOC dynamics in soils receiving biosolid amendments.