Fate of Biosolid Derived Organic Contaminants in Soils and Effects on Soil Microbial Communities

生物固体衍生的有机污染物在土壤中的归宿及其对土壤微生物群落的影响

• 批准号: 0854167
• 负责人: Claudia Gunsch
• 金额: $ 29.98万
• 依托单位: Duke University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2013-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0854167&HistoricalAwards=false
• 关键词: Fate; Biosolid; Derived; Organic; Contaminants

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).0854167GunschWastewater treatment processes do not efficiently remove all types of contaminants. The accumulation of these contaminants in biosolids is a growing concern because approximately 50% of biosolids in the United States are currently land-applied. Thus, there is potential for these pollutants to become mobilized in the environment following land-application of biosolids and cause adverse environmental effects. The principal objective of this proposal is to characterize the chemical fate of several organic contaminants, of various physicochemical properties, in soils and plants following biosolid land application. Furthermore, this project will explore microbial community dynamics and changes in denitrification function resulting from this process. Denitrifiers are key to nitrogen cycling and are linked to primary productivity and carbon decomposition. As such, denitrifying community dynamics are a good indicator of microbial function in soils. The contaminants chosen for this study are: 1) triclosan (a bactericide found in personal care products); 2) nonylphenol (a detergent/surfactant); 3) naproxen (pharmaceutically active compound a.k.a. Aleve) and; 4) two types of brominated flame retardants (BFRs). The working hypothesis of this project is that the rate of biosolid application will affect not only the contaminant fate, but impact microbial community structure and function. A series of experiments will be carried out in batch reactors and specially designed environmental chambers to test this hypothesis. At the conclusion of this study several metrics will be calculated to evaluate biosolid land application on environmental and soil health. These include: 1) soil retention factors of each contaminant ; 2) bioavailability of contaminants to plants cultivated in the soils; 3) the plant biomass production; and 4) by determining the threshold concentrations of each contaminant that is responsible for a significant microbial shift in microbial community structure and a 10% decrease in denitrification rate. This project will serve to further establish and strengthen collaborations between junior Faculty in the Pratt School of Engineering and the Nicholas School of the Environment at Duke University. This research will also enable both graduate and undergraduate students participating in this project to work in an interdisciplinary research team and gain valuable training. In addition, the PIs will continue to develop and implement an outreach program ("Scientists and Engineers for the Future") aimed at introducing underrepresented minority students in middle school to science and engineering so that they may make educated career decisions. The PIs are currently working with several middle school science teachers to develop work plans which integrate the students' curriculum with innovative hands-on activities representative of the biological sciences and environmental engineering. The PIs hope this outreach program will help these students make informed choices about career possibilities in science and engineering.

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。0854167 Gunsch废水处理工艺不能有效地去除所有类型的污染物。这些污染物在生物固体中的积累越来越令人担忧，因为美国目前大约50%的生物固体是土地应用的。因此，这些污染物有可能在土地上施用生物固体后在环境中移动，造成不利的环境影响。本提案的主要目的是描述几种有机污染物的化学命运，各种物理化学性质，在土壤和植物生物固体土地应用。此外，本项目还将探索微生物群落动态和由此过程导致的反硝化功能的变化。反硝化菌是氮循环的关键，与初级生产力和碳分解有关。因此，微生物群落动态是土壤中微生物功能的一个很好的指标。本研究选择的污染物为：1）三氯生（一种在个人护理产品中发现的物质）; 2）壬基酚（一种洗涤剂/表面活性剂）; 3）萘普生（药物活性化合物，Aleve）和; 4）两种类型的溴化阻燃剂（BFR）。本项目的工作假设是，生物固体的施用率不仅会影响污染物的归宿，而且会影响微生物群落结构和功能。一系列实验将在间歇反应器和专门设计的环境室中进行，以验证这一假设。 在这项研究的结论，几个指标将计算评估生物固体土地应用对环境和土壤健康。其中包括：1）每种污染物的土壤保留因子; 2）污染物对土壤中种植的植物的生物利用度; 3）植物生物量生产;以及4）通过确定每种污染物的阈值浓度，该阈值浓度是微生物群落结构中的显著微生物转变和反硝化速率降低10%的原因。该项目将进一步建立和加强普拉特工程学院和杜克大学尼古拉斯环境学院初级学院之间的合作。这项研究还将使参与该项目的研究生和本科生能够在跨学科研究团队中工作，并获得宝贵的培训。此外，土著人民协会将继续制定和实施一项外联方案（“未来的科学家和工程师”），旨在向中学中代表性不足的少数民族学生介绍科学和工程，使他们能够做出有教育意义的职业决定。PI目前正在与几位中学科学教师合作制定工作计划，将学生的课程与代表生物科学和环境工程的创新实践活动结合起来。PI希望这个推广计划将帮助这些学生对科学和工程的职业可能性做出明智的选择。