Measuring denitrification in the subsurface environment of Manawatu River Catchment

Abstract

Denitrification is an important nitrate (NO₃⁻) attenuation process in soil water systems. A sound understanding of this process will aid in the management and mitigation of the impacts of NO₃⁻ on groundwater and surface water quality. Denitrification in surface soils has been widely studied, but there are relatively few studies of its occurrence and distribution in the subsurface environment, particularly in the Manawatu River catchment, New Zealand. Challenges around the measurement of denitrification in the subsurface environment is one of the reasons that there has been limited research in this important area. Acetylene inhibition (AI) is a commonly employed method to measure denitrification in soil-water systems. However, subsurface denitrification studies using the AI method vary in methodological details, and this variation has implications for the reliability and comparability of results.