Evaluation of Flue Gas Desulfurization Gypsum As a Soil Amendment for Irrigated Crop Production in Nebraska.

Flue gas desulfurization gypsum (FGDG), a by-product of coal-fired electrical power generation plants, can have a range of beneficial uses in agricultural crop production as an alternative to landfill disposal. The 2-yr study was conducted to evaluate the potential for FGDG to improve soil quality and crop production on irrigated cropland in south-central Nebraska. Based on field maps for soil organic matter, soil apparent electrical conductivity, and pH, field length treatment strip locations were determined at two sites and FGDG was applied at four application rates (0, 1.2, 4.8, and 9.6 Mg/ha) in four replicates before planting in both fields. At each site, crop yield was measured manually at physiological maturity from geo-referenced locations in each treatment strip representing different topography and soil properties. This manual harvest was followed by combine harvest, after which soil samples were collected from same geo-referenced locations used during hand-harvest in each treatment strip at depth increments of 0-20 cm, 20-40 cm, and 40-60 cm. Besides regular agronomic analysis, both biomass and soil samples were also analyzed for selected metals. In the year (2014) of FGDG application, no significant treatment effect was observed with respect to crop yields and soil physical and chemical properties. No significant heavy metal accumulation was detected in either soils or crop biomass. This presentation will also have data included from the second year (2015).