2008 Annual Report
1a.Objectives (from AD-416)
We propose to evaluate FGD gypsum influences on soil properties that determine soil erodibility. The research will help establish proper rates of FGD gypsum to reduce runoff and erosion losses, and improve soil productivity. We will also provide documentation of water quality improvement associated with FGD gypsum needed to help qualify practices for use as a BMP and water quality improvement credits.
1b.Approach (from AD-416)
Two studies will be conducted at the Northeast Mississippi Experiment Station at Verona. In one study, we will evaluate the effects of FGD gypsum on an existing set of no-till cotton plots. The FGD gypsum application rates of 0, 1, 1.5, 2, and 3 tons/acre will be applied on a replicated plot experiment. The other study will evaluate the effects of tillage-gypsum interactions on soybean yields. The three tillage treatments are no-till, fall chisel-harrow, and conventional. Plot sizes, gypsum application rates, and replications are identical to those for no-till cotton. Crop yields will be measured by the experiment station personnel responsible for all agronomic practices. Following harvest each growing season, soil cores will be collected to a depth of 36 inches from each plot and characterized for water dispersible clay as a measure of erodibility, particle size distribution, organic carbon content, pH, exchangeable A1, exchangeable bases, total calcium, sulfur, nitrogen, and phosphorus.
This project seeks to determine the effects of amending soils with flue gas desulfurization (FGD) gypsum, a byproduct of air pollution control processes used at power plants, on several soil physical and chemical properties that influence soil erodibility and crop yields under different conservation tillage systems. Field plots were installed at the North Mississippi Research and Extension Center at Verona. Initial soil characterization samples were collected, and FGD gypsum was applied at rates of 0, 1, 2, 3, and 5 tons/acre to the replicated plot experiments. Crop response will be evaluated at different growth stages, and by measuring yields at the end of the growing season.