THE FLORIDA STATE UNIVERSITY ARTS AND SCIENCES ...

also implies that the transferability of reduction functions to other situations (e.g. soils
and environmental conditions) is questionable. The wide range of individual reduction
functions that exists in literature (Heinen, 2006) seems to indicate that the current models
are site specific. It is perhaps this lack of consensus on reduction functions and values
that has prevented the development of a generalized field scale model to predict the rate
of denitrification.
A widely useable simple field scale model for denitrification must take into account that
it would be near impossible to obtain an accurate site specific potential denitrification
rate to which a set of reduction functions can be applied. In addition as denitrification
may primarily be of a hot spot nature (Pabich, 2001), the ability to sample at the correct
location is critical to ensure that the correct potential denitrification rates can be obtained
multiple sampling will be required.
Further the calibration of the models often involves collection of additional data and
information which may lead to an increase in cost and time. This impediment may be
overcome by the development of a statistical based model which can predict the
denitrification rate using already existing data. As denitrification is primarily controlled
by the eleven factors mentioned in section 1.2, a natural choice would be to develop a
statistical relationship between all of the parameters and the denitrification rate. This will
allow the estimation of the denitrification rate based primarily on the environmental
conditions.
If denitrification is to be included in nitrogen cycling models or decision rules in a quick,
simple and effective way, simple denitrification functions need to be developed. The
framework for the model as described by Heinen (2006) is ideal with a slight
modification. Instead of having the denitrification rate as a function of potential
denitrification rate and other additional reduction functions, it is perhaps easier to have
the denitrification rate expressed directly in terms of these controlling factors.
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