Tuesday, November 6, 2007 - 2:10 PM
229-4
Manipulating Denitrification: Lessons Learnt from Riparian Research.
Many years of research have demonstrated that denitrification in riparian zones is an important mechanism for reducing non-point source pollution of surface waters. Further understanding of the environmental factors controlling denitrification at the catchment scale has also been developed in the studies of these ecosystems. Using these principles it is possible to manipulate the physical environment to enhance denitrification at sites where denitrification rates are low. Such approaches generally require the addition of a particulate organic matter source that provide an anaerobic environment and a carbon source that stimulates denitrification. Several approaches have been tested at field scale including denitrification walls for removing nitrate from groundwater, denitrification layers below topsoils at land treatment systems and denitrification beds for removing nitrate from point source discharges. I will explore the successes and failures of these approaches to date. A key message is that none of these approaches suit all conditions and it is important to match the approach to the hydraulic properties of the physical environment.
Audio File