|Bosch, David - Dave|
Submitted to: Cotton Research and Extension Report
Publication Type: Experiment Station
Publication Acceptance Date: 2/7/2001
Publication Date: 2/20/2001
Citation: BOSCH, D.D., POTTER, T.L., TRUMAN, C.C., BEDNARZ, C., HARRIS, G. TILLAGE EFFECTS ON PLANT AVAILABLE WATER, COTTON PRODUCTION AND SOIL/WATER QUALITY. COTTON RESEARCH AND EXTENSION REPORT. PP. 59-70. 2001.
Interpretive Summary: Conservation tillage has significant potential as a management tool for cotton production on sandy soils that are drought-prone and susceptible to erosion. Minimizing soil disturbance can reduce irrigation requirements and runoff, which in turn reduces the transport of sediment, nutrients, pesticides, and other agrichemical residues into surface waters. While potential benefits of conservation tillage are widely recognized, actual benefits in terms of water conservation and quality vary considerably, depending on numerous factors including soil characteristics, topography, pest pressure, agrichemical use, and weather. To better characterize some of these differences, a collaborative research effort was established to systematically evaluate impacts of strip-tillage on water quantity and off- site water quality. Strip-till was found to conserve soil water while reducing runoff and sediment transport when compared to conventional-till. These results should be of interest to growers and water managers who are concerned with optimizing water use to lower production costs while protecting water quality.
Technical Abstract: A 4.6-acre parcel on the UGA Gibbs Farm located in Tift County, GA was used to better characterize the impact of conservation tillage on soil runoff, erosion, and agrichemical transport. While the potential benefits of conservation tillage are widely recognized, actual benefits in terms of water conservation and quality vary considerably, depending on numerous factors including soil characteristics, topography, pest pressure, agrichemical use, and weather. The site was divided into six half-acre plots with a seventh 1-acre plot set aside for companion rainfall simulation studies. Half of the plots were managed with conventional- tillage while the other half were strip-tilled. Surface runoff and groundwater samples were collected to characterize water flow and transport. Findings from the study indicate that strip-till improves soil infiltration while reducing runoff and sediment transport compared to conventional-till. Some potentially negative observations associated with strip-till included enhanced herbicide leaching and higher loss rates of dissolved defoliant residues in runoff. Yields from the strip-till plots were competitive with those from the conventional-till plots. As subsequent crops are produced on the plots and environmental monitoring continued, more definitive data will be available to evaluate positive and negative aspects of strip-till versus conventional-till.