Collaborative Research: Assessing the bioavailability of effluent organic nitrogen along a freshwater to saltwater continuum

这项拟议研究的目标是解决提供生物去除营养物质的有机氮(EON)废水处理设施的生物可利用性。这项研究的目的是提供基本信息，以导致可靠的生物测定，以确定污水厂排放的EON对接收地表水的影响和对富营养化的贡献。介绍了影响地表水有机氮有效性的已知因素的良好背景，并反映了这个合作研究小组的不同背景：环境工程师、生物海洋学家、有机地球化学家和化学海洋学家。研究的基本假设是，EON的生物有效性与盐度、浓度和光照有关，地表水中的生物群在不同的盐度位置可能不同，可能具有不同的EON转化和吸收特征。本研究将考察不同种源对EON生物利用度的影响。该提案提供了一项计划，以评估生物种群、藻类的生长水平。叶绿素a测量，基于分子量大小的EON的可用性，以及应用化学方法评估EON的元素组成和分子表征。开发EON生物利用度的生物测定方法并确定废水、工厂废水中可生物降解的量的能力将产生深远的影响。首先，它将为水质管理人员和建模人员提供科学依据，以确定是像现在一样处理所有流出的氮，还是考虑不影响富营养化活动从而不会导致形成对鱼类有害的低氧条件的可能的顽固性部分。生物分析工具可以帮助指导污水处理厂的设计，因为不同操作的流出物可以用来确定不同的设计或操作条件是否会影响EON的生物有效性。其他重要的影响是一所暑期迷你学校，它可以利用这个项目和切萨皮克湾地区的水质问题作为当地的真实情景，供公众研究。这项工作将是对大规模问题进行跨学科研究的展示和样板。这种类型的培训和教育将对参与该项目的研究生产生长期影响。作为过去NSF研究的一部分，PI还为本科生提供了成功的暑期研究经验。

CBET-0755826MulhollandThe objective of this proposed study is to address the bioavailability of effluent organic nitrogen (EON)) wastewater treatment facilities which provides biological nutrient removal. The research is intended to provide basic information that can lead to reliable bioassays to determine the effect of a wastewater plant discharge EON on the receiving surface water and contribution to eutrophication. An excellent background on known factors that affect the availability of organic nitrogen in surface waters was presented and reflected the diverse backgrounds of this collaborative research group; environmental engineer, biological oceanographer, organic geochemists, and chemical oceanographer. Basic hypothesis for the research is that the bioavailability of EON is related to salinity concentration and light and that the biota in the surface water may be different at different salinity locations and possibly have different EON conversion and uptake characteristics. The research would investigate the effect of different seed sources on the EON bioavailability. The proposal provides a plan to assess the biological populations, the level of algae growth by. Chlorophyll a measurement, the availability of the EON based on molecular weight size, and application of chemistry methods to assess the elemental composition of the EON and molecular characterization. The ability to develop a bioassay for the bioavailability of EON and to determine what amount from wastewater plant effluents is biodegradable will have far reaching impacts. First it would provide water quality managers and modelers scientific basis on whether to treat all effluent nitrogen as bioavailable as they now do or to account for a possible recalcitrant fraction that has not affect on eutrophication activity and thus does not contribute to developing hypoxia conditions that are harmful to fish. The bioassay tool can help guide wastewater plant designs as effluents from different operations can be used to determine if different design or operating conditions affect the EON bioavailability. Other important impacts are a summer mini school that can use this project and water quality issues in the Chesapeake Bay area as local and real scenario for study by the public. The work will be showcase and model for interdisciplinary research on a large scale problem. This type of training and education will have a long term impact on the graduate students working on the project. The PIs have also had successful summer research experiences for undergraduates as part of past NSF studies.