Bioavailability and Biodegradation of Organic Contaminants In Heterogenous Subsurface Environments

异质地下环境中有机污染物的生物利用度和生物降解

• 批准号: 9523870
• 负责人: Raina Maier
• 金额: $ 41万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-10-01 至 1999-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9523870&HistoricalAwards=false
• 关键词: Bioavailability; Biodegradation; Organic; Contaminants; Heterogenous

9523870 Miller Bioavailability and Biodegradation of Organic Contaminants in Heterogeneous Subsurface Environments. One of the most promising and cost-effective environmental cleanup technologies for contaminated soil and groundwater is in situ bioremediation. In situ bioremediation is the use of microorganisms to restore a contaminated environment without having to excavate or otherwise disturb the contaminated site. Many natural environments contain microbial communities capable of degrading (destroying) pollutants. There are two serious problems facing successful implementation of in situ bioremediation. These are the physical and chemical heterogeneities found in natural environments, and the reduced availability of contaminants that results from the sorption (sticking) of contaminants to solid surfaces (clay or sand particles). The goal of this project is to use an integrated biological and physical/chemical approach to investigate the factors controlling bioremediation in natural (heterogeneous) subsurface environments. This proposal outlines a unique approach to understanding the effect of heterogeneity on contaminant availability, and how availability constraints can be overcome to enhance the magnitude and rate of bioremediation. This approach combines state-of-the-art intermediate-scale flow and transport experiments with an advanced technique for the determination of both the number and activity of contaminant-degrading microorganisms (fiber optic detection of luminescing microorganisms). This approach will allow the simultaneous detection of contaminant transport and microbial activity, which will allow for the investigation of the relationship between spatial heterogeneity and availability of contaminants for microbially-mediated destruction. In addition, the approach will be used to evaluate the physical and biological parameters that control the transport of microorganisms in a heterogeneous environment, and to relate microbial mechanisms for enhanced transport to their potential to enhance the degradation of inaccessible organic contaminants. The approach will also be used to evaluate strategies to enhance in situ bioremediation, for example, the application of surfactants (detergents) that may increase the availability of sorbed contaminants. The results of the research will improve our understanding of these issues and will provide significant advancement in prediction of contaminant transport and fate, for evaluating groundwater contamination potential, and for the manipulation of subsurface systems to enhance the effectiveness of bioremediation technologies.

9523870米勒生物利用度和生物降解的有机污染物在异质地下环境。 原位生物修复技术是污染土壤和地下水最有前途和最具成本效益的环境净化技术之一。 原位生物修复是利用微生物恢复受污染的环境，而不必挖掘或以其他方式破坏受污染的场地。许多自然环境含有能够降解（破坏）污染物的微生物群落。成功实施原位生物修复面临两个严重的问题。 这些是在自然环境中发现的物理和化学不均匀性，以及由于污染物吸附（粘附）到固体表面（粘土或沙粒）而导致的污染物可用性降低。 该项目的目标是使用综合的生物和物理/化学方法来调查自然（异质）地下环境中控制生物修复的因素。 该提案概述了一种独特的方法来了解异质性对污染物可用性的影响，以及如何克服可用性限制，以提高生物修复的幅度和速度。 这种方法结合了最先进的中等规模的流动和运输实验与先进的技术，用于确定污染物降解微生物的数量和活性（发光微生物的光纤检测）。 这种方法将允许同时检测污染物的运输和微生物活性，这将允许调查的空间异质性和微生物介导的破坏污染物的可用性之间的关系。 此外，该方法将用于评价控制微生物在异质环境中迁移的物理和生物参数，并将微生物增强迁移的机制与其增强难以接触的有机污染物降解的潜力联系起来。该方法也将被用来评估战略，以提高原位生物修复，例如，应用表面活性剂（洗涤剂），可能会增加吸附污染物的可用性。研究的结果将提高我们对这些问题的理解，并将提供显着的进步，预测污染物的运输和命运，评估地下水污染的潜力，并操纵地下系统，以提高生物修复技术的有效性。