Carole L. Jaworski
Cornelis G. Hoogeweg, Arthur H (352) 392-1951
GAINESVILLE-A new computer software program, developed by a University of Florida graduate student from the Netherlands, will help protect Florida’s drinking water from pesticide contamination. With minor tweaking, it could have worldwide application.
More than 80 percent of Florida’s drinking water comes from underground sources, says Cornelis G. Hoogeweg, soil and water science graduate research assistant with the UF’s Institute of Food and Agricultural Sciences. But pesticides and other chemicals used in the production of Florida agricultural crops could contaminate groundwater supplies. In fact, several pesticides have already been detected in ground and surface waters.
“The pesticide contamination prediction system-called SEAMS (Soil Environmental and Agricultural Management System)-is user-friendly,” Hoogeweg says. “So friendly, in fact, that users-farmers, policy makers, educators, regulators, and researchers who need a tool to predict pesticide behavior in a three-dimensional world-don’t even need to own a computer. The reason is, Florida’s county extension agents are being trained to run the computer simulation program for them.” That three-day training began June 24 at UF.
The software will be released in September, when the U.S. Environmental Protection Agency and 55 out of 67 Florida counties will receive it. Counties that do not have their soil maps digitized will not receive the software.
SEAMS builds on, and combines features from, several different computerized programs: the Chemical Movement in Layered Soils model, the Geographic Information Systems (GIS), ArcView, a weather generation program (WGEN), and Florida’s county-by-county digitized soils databases.
The result of this combination of models, interfaces, and databases is more than a sum of its parts: It is a simple tool that can predict pesticide contamination of groundwater.
“It’s a great screening tool if you need a quick analysis of groundwater vulnerability to pesticide,” he says. “It’s better than EPA’s present system-an index method to quantify groundwater vulnerability-because it takes individual pesticide properties and drinking water standards into consideration. As for EPA’s other two screening models, SEAMS does an equally good job and requires less input data.”
Users can select from several pesticide classes: growth regulators, fungicides, fumigants, herbicides, insecticides, miticides, and nematicides. The list is automatically updated for each crop. Based on the selected crop and treatment, a list of recommended pesticides for the site appears. More than one pesticide at a time can be selected. Five pesticide application parameters are also selected: minimum and maximum application rate, application depth, and application beginning and end dates.
The software prompts the user to select land-use types, such as fallow, row crops, and small grains; management practices, such as straight row, conservation tillage, contoured, terraced, or a combination; and crop cover conditions to estimate runoff and infiltration of precipitation.
Pesticide leaching appears as maps or as the probability of exceeding EPA’s health advisory levels. The maps, created by GIS, don’t need much interpretation, he says. “They’re very clear. Green is safe and red is hazardous.”
The program is so user friendly that, if you have not properly selected an application area, a warning window pops up with the message: “Bummer. No Application Areas Selected.”
Right now, the list is valid only for Florida, but that’s because only the pesticides registered for use in Florida have been incorporated into the model. The model could easily be retrofitted for use elsewhere.
“This software can be used anywhere in the world that has digitized soil maps and the type of soil data used in the model,” says Arthur Hornsby, UF/IFAS soil and water science professor.
The GIS technology used in the model was developed in the early 1960s and came out of the need to map the moon. It allows the user to analyze, manipulate, store, retrieve, and visualize data. The first application of GIS was 35,000 years ago, Hoogeweg says, in the cave paintings in France. There, early humans drew the migration route of deer along with pictures of their prey. In essence, maps were combined with data, which is characteristic for GIS.
For more information on the new software, Hoogeweg can be contacted by e-mail at email@example.com; by phone at (352) 392-1951; or by a home page on the internet at .