PRZM Harmonization with the EU FOCUS Models
The Pesticide Root Zone Model (PRZM) was first released by the US Environmental Protection Agency (USEPA) in 1984 to simulate the vertical movement of pesticides in the unsaturated soil. Since the model’s inception, Waterborne staff have been involved with the development and enhancement of PRZM. This includes implementing a European specific version, created by the FOCUS group, to handle standard scenarios. Waterborne recently made significant changes to PRZM’s code to improve the model’s functionality.
The first set of enhancements were made to improve PRZM’s use for watershed modeling. These changes included a new sub-lateral flow routine to more closely represent tile drainage, a change to the evapotranspiration routine in order to allow the use of FAO irrigation and drainage paper 56 based technology, and run-on/run-off buffer model utilization.
The second set of enhancements were made to increase PRZM’s harmonization with the FOCUS group’s PEARL, MACRO and PELMO models. These improvements included the addition of aged sorption kinetics, user-defined dispersion lengths and a daily irrigation file.