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Fosnrs 6: Stumod-FL - a Tool for Predicting Fate and Transport of Nitrogen in Soil Treatment Units in Florida.
See more from this Division: Oral sessionsSee more from this Session: TRACK 1--Treatment and Fate of Contaminants: Nitrogen
STUMOD-FL accounts for evapotranspiration and the effect of high/seasonally variable water tables on nitrogen removal in soil and incorporates up to four soil layers including the biomat. The effects of ET are expressed in two primary ways: root water uptake and root nutrient uptake. The potential evapotranspiration is calculated using Hargreaves Method. The actual evapo-transpiration is calculated from the potential evapotranspiration with adjustment factors to account for soil moisture content and root distribution. The nutrient uptake is driven primarily by plant nutrient demand but also the actual ET and concentration of nutrients in the soil water. The root water uptake has a flexible formulation that considers a maximum allowable uptake, plant nutrient demand, and soil water nutrient availability uptake mechanisms through ET. STUMOD-FL estimates the water table fluctuations in response to precipitation based on one-dimensional flow in unconfined aquifers. Assumptions in the model development include that the major cause of water table fluctuation is precipitation and that the time lag from precipitation to water table response is negligible.
Nitrogen species concentrations and the fraction of total nitrogen reaching the aquifer and mass flux is estimated by STUMOD-FL at user specified soil depths based on user input data including hydraulic loading rate, sorption, nitrification and denitrification rates. The effect of soil moisture content (a surrogate for redox conditions) is accounted for in nitrification and denitrification reactions. STUMOD-FL predictions are being compared to controlled pilot-scale test site data on nitrogen fate and transport under a variety of typical operating conditions. Model outputs provide insight into the behavior of soil treatment and quantitative estimations of nitrogen removal as affected by a range of conditions.
See more from this Session: TRACK 1--Treatment and Fate of Contaminants: Nitrogen