A simple denitrification model? Literature review, sensitivity analysis, and application

Denitrification is a complex process. In literature, this process is mostly described by a simplified process model. From a literature review, the consensus model describes the actual denitrification rate as being equal to some potential denitrification rate subsequently reduced by soil environmental conditions. Typically, potential denitrification is reduced by nitrate content, degree of saturation (water content) as a measure for anaerobic conditions, soil temperature, and possibly soil pH. There is, however, much less consensus about the actual shape of the reduction functions. This indicates that these reduction functions are site (soil) specific. From a sensitivity analysis it follows that this model is most sensitive to the water content reduction function. Available data sets were used to determine if these can be used to parameterize the reduction functions. It appears that this is rather difficult, since mostly the measured actual denitrification rate is much less than the potential denitrification rate. Therefore, the reduction functions need to be determined independently.