『Abstract
Sediment denitrification is a major pathway of fixed nitrogen
loss from aquatic systems. Due to technical difficulties in measuring
this process and its spatial and temporal variability, estimates
of local, regional and global denitrification have to rely on
a combination of measurements and models. Here we review approaches
to describing denitrification in aquatic sediments, ranging from
mechanistic diagenetic models to empirical parameterizations of
nitrogen fluxes across the sediment-water interface. We also present
a compilation of denitrification measurements and ancillary data
for different aquatic systems, ranging from freshwater to marine.
Based on this data compilation we reevaluate published parameterizations
of denitrification. We recommend that future models of denitrification
use (1) a combination of mechanistic diagenetic models and measurements
where bottom-waters are temporally hypoxic or anoxic, and (2)
the much simpler correlations between denitrification and sediment
oxygen consumption for oxic bottom waters. For our data set, inclusion
of bottom water oxygen and nitrate concentrations in a multivariate
regression did not improve the statistical fit.
Keywords: Denitrification; Diagenetic model; Sediment』
Abbreviations
Introduction
Model approaches
Steady-state models
Layered dynamic models
Microenvironments
Parameterizations
Data
Data compilation
Mean tendencies
Environmental control on N cycling processes
Application of data to models
Regression analysis
Phosphate fluxes
Diagenetic model versus parameterization
Conclusions
Acknowledgments
References