Denitrification capacity and potential in the Toenepi catchment

Abstract

A discrepancy is often observed between the amount of nitrate (NO3-) estimated to be leaching from the root zone of agricultural land, and NO3- concentrations measured in associated surface waters. This reduction in NO3- concentrations is often the result of denitrification in the shallow groundwater. Determining where, when and how much denitrification occurs in situ can be challenging, especially when flow paths in a catchment are not well defined. Laboratory incubation experiments can be used to investigate denitrification and understand the factors limiting the process in situ.