Impacts of Green Infrastructure on the Microbiome of Urban Stormwater: Reducing Threats to Public Health

包括生物滞留单元在内的绿色基础设施越来越多地被用作传统城市排水系统的更可持续的替代方案。虽然在雨水管理的许多方面都得到了成功的应用，但人们还没有真实的了解这些系统是否或如何提供公共卫生服务，例如控制人类病原体的传播。雨水中粪便指示细菌（FIB）的浓度通常超过人类接触的安全水平;然而，FIB并不是实际病原体的良好指标。这突出表明需要确定实际致病病原体的丰度和多样性，并确定生物滞留如何减少其对下游水体的贡献。该项目将通过分析雨水的微生物组和评估生物滞留系统在减少雨水中一系列微生物对人类健康和环境质量的威胁方面的有效性来满足这一需求。过去对雨水处理技术有效性的研究受到限制，因为传统的方法和分析方法只能追踪有限的细菌物种，这些细菌物种丰富且易于培养，如E。大肠杆菌或大肠菌群。使用第三代测序来识别微生物物种，研究人员将量化丰度，多样性和抗菌素耐药性（AMR）基因，以描述雨水的微生物组。该研究旨在确定：（1）如果对雨水中细菌亚群（FIB）的常规监测足以代表完整的微生物组，包括实际的人类病原体，或者如果需要对微生物组进行更广泛的监测，以及（2）如果雨水处理技术-在这种情况下是生物滞留系统-可以减少病原菌和AMR基因，而不是FIB追踪的这些有害污染物的替代子集。通过生物滞留设计挑战赛，其中包括实地考察的实验流域，七年级和八年级的学生从哥伦布市学校将学习第一手如何设计生物滞留系统，以及如何收集现场和实验室数据来测试假设。由于超过70%的哥伦布市学生是少数民族，这将提高代表性不足的群体在STEM教育中的参与。这项研究的一个重大社会效益将是确定通过绿色基础设施减少雨水病原体的设计组件。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Green infrastructure, including bioretention cells, is increasingly used as a more sustainable alternative to traditional urban drainage. While successfully employed in many aspects of stormwater management, there is as yet no real understanding of whether or how these systems provide public health services, such as controlling the spread of human pathogens. Concentrations of fecal indicator bacteria (FIB) in stormwater routinely exceed safe levels for human contact; however, FIBs are not good indicators of actual pathogens. This highlights the need to determine the abundance and diversity of actual disease-causing pathogens and to determine how bioretention reduces their contribution to downstream water bodies. This project will address this need by analyzing the microbiome of stormwater and evaluating the effectiveness of bioretention systems in reducing a range of microbial threats in stormwater to human health and environmental quality. Past studies of the effectiveness of stormwater treatment technologies have been limited because conventional approaches and analytical methods only track limited bacterial species that are abundant and easy to culture, such as E. coli or coliforms. Using third generation sequencing to identify microbial species, the investigators will quantify abundance, diversity and antimicrobial resistance (AMR) genes to describe the microbiome of stormwater. The research is targeted to determine: (1) if conventional monitoring of subsets of bacteria (FIB) in stormwater is a sufficient proxy of the complete microbiome, including actual human pathogens, or if more extensive monitoring of the microbiome is warranted, and (2) if stormwater treatment technologies - in this case bioretention systems - can reduce pathogenic bacteria and AMR genes, as opposed to proxy subsets of these harmful pollutants as tracked by FIB. Through a Bioretention Design Challenge that includes field trips to the experimental watersheds, 7th and 8th grade students from Columbus City Schools will learn first-hand how to design bioretention systems and how to collect field and laboratory data to test hypotheses. Because more than 70% of Columbus City students are minorities, this will enhance the participation of underrepresented groups in STEM education. A significant societal benefit from this research will be the identification of design components that enhance stormwater pathogen reductions by green infrastructure.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.