Research TRACEs Soil Erosion

May 14, 1997

Greensboro, NC: An extensive effort involving the research, instruction and extension components of the North Carolina A&T State University School of Agriculture, the TRACE research project has important implications for tillage practices and erosion prediction technology both locally and nationally.

TRACE represents Tillage Runoff, Agricultural Chemicals and Erosion, all research components within this long-term project. Researchers hope that the results of TRACE will help farmers improve their growing methods while increasing their profits and preserving the environment by minimizing soil erosion.

"The final intent of our work is to reach end users (farmers) through Extension, so that they can realize better production and profits," said Dr. Godfrey Gayle, chairperson of the NC A&T Department of Natural Resources and Environmental Design, and one of TRACE's principal researchers.

To do this, TRACE researchers are studying four different tillage treatments: conventional tillage, which involves chisel plowing and disk harrowing; strip tillage, in which only the planted portion of the soil is tilled; no-till/controlled traffic tillage, in which the soil is not tilled and tractor tires are restricted to designated lanes; and no-till/full traffic tillage, in which all soil is compacted.

According to Dr. Charles Raczkowski, assistant professor of soil science at A&T, the no-till/full traffic treatment represents a worst-case scenario. "The adverse effects of wheel compaction are being evaluated in this treatment," said Raczkowski. "This will demonstrate to farmers how important it is to control vehicular traffic in no-till methods."

According to Raczkowski, traffic control can be achieved by establishing permanent traffic lanes.

All of the test plots are located on A&T's farm complex just east of Greensboro. Each plot is monitored using a system of pipes and containers from which runoff volume, and pesticide, nutrient and soil losses are collected and measured.

"The different plots allow us to simulate realistic farming practices," said Dr. Manuel Reyes, assistant professor of Agricultural and Biosystems Engineering at A&T. "In order for our data to be accurate, the testing must be thorough."

Gayle believes that improved erosion control methods can result in increased profits for farmers. "Though the results of a change in tillage practices aren't always immediately noticeable, in the long run, farmers should be able to cut back on their labor and chemical input costs, due to improved soil quality and structure. The reduction in costs and the improved fertility of the soil should translate into a higher profit margin."

In addition to Reyes, Gayle and Raczkowski, Dr. G. B. Reddy and technical field assistants Leon Moses and Aminu Yaro are intensively involved in specialized aspects of TRACE. Reddy, a soil microbiologist, is responsible for the chemical analysis, while Moses is responsible for preparing the test plots, and Yaro is responsible for sampling after rain. All are involved in the overall experiment design.

The data obtained from the TRACE research are used in a number of ways. Among them are testing four erosion and water quality computer modeling programs used by the United States Department of Agriculture, and as additions to the database used by USDA model developers.

In 1994, the NC A&T School of Agriculture was awarded a grant by USDA to study and compare the four erosion and water quality models. Each computer assisted model was developed by scientists working through USDA to analyze and predict erosion.

At A&T, data collected through TRACE are inputted into each of the models to test the model's accuracy in prediction, and to determine its ease of use. Evaluators then rate the models and submit their evaluations to USDA.

"All of the models were originally tested by their creators, but this is the first time that so many have been compared by independent testers," said Reyes. "USDA hopes that our results will help the model developers improve on the existing technology."

A 1996 USDA capacity-building grant has enabled A&T faculty to extend TRACE to both graduate and undergraduate students in A&T's School of Agriculture. Grant money has been used to support ten A&T biosystems engineering students as erosion and water quality modeling scholars who study one of the USDA models.

"Students are involved with the intention that, once they graduate and pursue careers outside of A&T, they will disseminate what they have learned to others," said Gayle. "As far as we know, we are the only institution to offer undergraduates the opportunity to be trained in, and receive pay for, studying an erosion model to this extent."

The grant has also been used to offer A&T students a course in erosion and water quality modeling.

The benefits of TRACE research and related information of have not been limited to A&T faculty and students, and USDA. Workshops in the different models are open to the public, and have been attended by a variety of professionals.

TRACE research has also been presented at number of professional meetings across the country.
Plans are also underway to offer workshops and tours to the state's farmers through A&T's Cooperative Extension Program.

USDA personnel involved with TRACE include: Dr. George R. Foster, Sedimentation Laboratory, Oxford, Mississippi; Dr. James L. Fouss, Mid South Area, Soil and Water Management Research, Baton Rouge, Louisiana; Dr. Jerry Lemunyon, South Technical Center, Fort Worth, Texas; Drs. Glenn A. Weesies and John M. Laflen, National Soil Erosion Research Lab, West Lafayette, Indiana; Dr. Ralph A. Leonard, Southeast Watershed Research Laboratory, Tifton, Georgia; and Dr. Jimmy R. Williams, Grassland, Soil and Water Research Laboratory, Temple, Texas.

- 30 -

For more information, please contact Dr. Godfrey Gayle, NC A&T School of Agriculture, (336) 334-7543, or Dr. Manuel Reyes at (336) 334-7787.