Submitted to: Use of Organic and Inorganic Amendments Derived from Waste By-Products
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 2, 2001
Publication Date: August 1, 2002
Citation: Livingston, S.J., Norton, L.D., Edwards, J.H., Aiken, G.E. Co-utilization of organic and inorganic waste to alleviate plant nutrient imbalances: II. Rainfall simulator studies. Use of Organic and Inorganic Amendments Derived from Waste By-Products to Alleviate Soil Nutrient Imbalance. Proceedings of a Workshop. 2002. p. 22-31. Interpretive Summary: The problem studied was high phosphorous contents and adverse environmental impact. This study was conducted to determine the effects of soil amendments on the amount of water soluble phosphorous (WSP) and total phosphorous (TP) in runoff and sediment. We conducted a study with a rainfall simulator on a field where chicken and cattle manure has been surface applied for the past 40 years. The treatments evaluated surface applied gypsum and surface applied gypsum over mixed processed paper mulch on phosphorous losses under cropland and pasture. Amendments along with tillage had a positive effect on the amount of WSP and TP in the runoff and sediment. Undistrurbed pasture plots with no amendments had greater amounts of WSPint he runoff than the pasture sites forall other amendment and surface types. Gypsum amendments had lesser amounts of WSP in the runoff than all other amendments for all surface conditions. The most effective treatment was the disturbed gypsum while the least effective was the untreated pasture. WSP amounts did not vary with increasing runoff rates. The disturbed surface with gypsum or paper amendments reduced the WSP amount in the runoff on the soil series studied due to mixing the TP throughout the top 10inches of the soil. The amount of TP in the sediment collected was measured for the disturbed conditon and indicate that the untreated sites contain a greater amount of TP than either gypsum or paper treatments. The impact of this research is that producers with high P in their soils can reduce off-site eutriophication by a combination of tillage and by adding soil amendments. All society will benefit from improved water quality.
Technical Abstract: This study was conducted to determine the effects of soil amendments on the concentration of soluble reactive phosphorous (SRP) and total phosphorous (TP) in runoff and sediment using the Norton rainfall simulator on a field where poultry and cattle manure has been surface applied for the past 40 years. The effect of surface applied gypsum, and surface applied gypsum over incorporated processed paper mulch, on phosphorous losses under cultivated and pasture condition were studied. The study was conducted on a Fine, smectitic, thermic Udertic Paleustalf (Zulch series), near College Station, TX. Twelve plots under pretreated pasture conditions and 12 plots of disturbed land with treatments applied just prior to simulated rainfall were studied. Pasture plots had greater (3.8 mg L-1) concentrations of SRP in the runoff than the pasture sites (2.6 mg L-1) across amendment types. Gypsum amendments had lesser (2.45 mg L-1) concentrations of SRP than all other amendments (paper 3.11 mg L-1, control 4.09 mg L-1) across surface conditions. The most effective treatment was the disturbed gypsum (1.65 mg L-1 SRP) while the least effective was the pasture control (4.5 mg L-1 SRP). SRP concentrations did not vary significantly with increasing runoff rates. The disturbed surface with gypsum or paper amendments reduced the SRP concentration in the runoff on the soil series studied due to mixing the TP throughout the Ap horizon. Concentrations of SRP did not change with increasing runoff volumes. TP concentrations in sediment delivered were measured for the disturbed sites and indicate the control (2.91 kg ha hr-1) was greater than both the gypsum (0.165 kg ha hr-1) and paper (0.31 kg ha hr-1).