Title: | Gas-phase and transpiration-driven mechanisms for volatilization through wetland macrophytes |
Address: | "Department of Civil and Environmental Engineering, Princeton University, Princeton, New Jersey 08544, United States. mcreid@princeton.edu" |
ISSN/ISBN: | 1520-5851 (Electronic) 0013-936X (Linking) |
Abstract: | "Natural and constructed wetlands have gained attention as potential tools for remediation of shallow sediments and groundwater contaminated with volatile organic compounds (VOCs). Wetland macrophytes are known to enhance rates of contaminant removal via volatilization, but the magnitude of different volatilization mechanisms, and the relationship between volatilization rates and contaminant physiochemical properties, remain poorly understood. Greenhouse mesocosm experiments using the volatile tracer sulfur hexafluoride were conducted to determine the relative magnitudes of gas-phase and transpiration-driven volatilization mechanisms. A numerical model for vegetation-mediated volatilization was developed, calibrated with tracer measurements, and used to predict plant-mediated volatilization of common VOCs as well as quantify the contribution of different volatilization pathways. Model simulations agree with conclusions from previous work that transpiration is the main driver for volatilization of VOCs, but also demonstrate that vapor-phase transport in wetland plants is significant, and can represent up to 50% of the total flux for compounds with greater volatility like vinyl chloride" |
Keywords: | "Biodegradation, Environmental Gases/*analysis Kinetics Meteorological Concepts Models, Biological Plant Transpiration/*physiology Plants/*metabolism Rhizome/metabolism Rhizosphere Sulfur Hexafluoride/analysis Temperature Typhaceae/metabolism Volatilizatio;" |
Notes: | "MedlineReid, Matthew C Jaffe, Peter R eng Research Support, U.S. Gov't, Non-P.H.S. 2012/04/19 Environ Sci Technol. 2012 May 15; 46(10):5344-52. doi: 10.1021/es203297a. Epub 2012 Apr 30" |