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PRZM3 - pesticide transport model - exposure assessments
PRZM3 Category: solute transport models - unsaturated zone
PRZM3 Overview
PRZM3 links two models, PRZM and VADOFT to predict pesticide transport and
transformation down through the crop root and vadose (unsaturated) zone to the water table. PRZM3 incorporates soil temperature simulation, volatilization and vapor phase transport in soils, irrigation simulation,
and microbial transformation. PRZM is a one-dimensional finite-difference model which uses a method of characteristics (MOC) algorithm to eliminate numerical dispersion. VADOFT is a one-dimensional finite-element
code that solves Richards' equation for flow in the unsaturated zone. The user may make use of constituting relationships between pressure, water content, and hydraulic conductivity to solve the flow equation. PRZM3
is capable of simulating multiple pesticides or parent-daughter relationships. PRZM3 is also capable of estimating probabilities of concentrations or fluxes in or from various media for the purpose of performing
exposure assessments. PRZM and VADOFT are linked together with the aid of a flexible execution supervisor that allows the user to build models that are tailored to site-specific situations. Monte Carlo pre and
postprocessors are provided in order to perform probability-based exposure assessments.
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