Read: an article describing this work in Agricultural Research

Easy-to-Use Computer Model Helps Illustrate Water Movement Through Soil

A user-friendly, sophisticated computer model developed by the Agricultural Research Service has helped engineers, scientists and students worldwide understand how water and chemicals move in soil and groundwater.

HYDRUS allows agricultural engineers to design irrigation systems that provide optimal water to crops while minimizing the transport of fertilizers and pesticides to groundwater. Landfill designers have used the program to ensure their facilities do not release contaminants.

Dozens of scientists and students contributed to HYDRUS, which was developed at ARS' George E. Brown, Jr., Salinity Laboratory in Riverside, Calif. ARS soil scientist Rien van Genuchten and University of California civil engineer Jirka Simunek are lead authors of the computer program.

The model continues to evolve, thanks to a cooperative research and development agreement with the Colorado School of Mines' International Ground Water Modeling Center (IGWMC) in Golden. IGWMC distributes the model, provides hands-on help to users, runs short-courses on the model, and gives feedback to ARS so that the researchers can improve HYDRUS.

So far, IGWMC has sold more than 500 copies of the model worldwide, and has conducted courses on the model in the U.S., Europe and Australia.

HYDRUS provides an easy-to-use, Windows-based format. It displays results visually by means of graphs or contour lines, instead of as columns of numbers. Animation can illustrate how a fertilizer or other chemical would move through the soil and possibly into groundwater.

An article describing this work appears in the May issue ofAgricultural Research, ARS' monthly magazine.

Demonstration versions of the model are online at:

http://www.ussl.ars.usda.gov/MODELS/HYDRUS2D.HTM

and

http://www.mines.edu/research/igwmc/zipfiles

ARS is the chief research agency of the U.S. Department of Agriculture.

Scientific contact: Rien van Genuchten, Soil Physics and Pesticide Research Unit, ARS George E. Brown, Jr., Salinity Laboratory, Riverside Calif., phone (909) 369-4847, fax (909) 342-4964, [email protected].