Temperature Coefficient for Modeling Denitrification in Surface Water Sediments Using the Mass Transfer Coefficient
Watershed modeling has become an important tool for researchers with the high costs of water quality monitoring. When modeling nitrate transport within drainage networks, denitrification within the sediments needs to be accounted for. Birgand et. al. developed an equation using a term called a mass transfer coefficient to mathematically describe sediment denitrification. This equation takes into account the effect that water column nitrate concentration and flow depth have on sediment denitrification. Water column temperature also has a marked effect on the rate of denitrification in sediment. A relationship of temperature to denitrification rate was developed using information presented by Dawson and Murphy. This relationship was inserted into the mathematical relationship developed by Birgand et al. to improve its' ability to prediction nitrate removal due to denitrification within drainage networks. The modified equation was tested by comparing measured nitrate concentrations over time from denitrification tanks with varying temperatures with predicted concentrations. Results show that the modified equation increased the accuracy of predicting nitrate removal through denitrification from sediment in drainage networks.