|NETTHISINGHE, A.M.P. - Western Kentucky University|
|WOOSLEY, P.B. - Western Kentucky University|
|GILFILLEN, R.A. - Western Kentucky University|
|WILLIAN, T.W. - Western Kentucky University|
|ROWLAND, N.S. - Western Kentucky University|
Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/30/2016
Publication Date: 7/28/2016
Citation: Netthisinghe, A., Woosley, P., Gilfillen, R., Willian, T., Sistani, K.R., Rowland, N. 2016. Corn grain yield and soil properties after 10 years of broiler litter amendment. Agronomy Journal. 108:1-8.
Interpretive Summary: Kentucky is the seventh largest broiler chicken producing state in the U.S. with over 308 million broilers produced annually. Broiler production results in large volumes of broiler litter as a byproduct. Disposing large quantities of poultry litter can also provide an economic opportunity to improve crop yields and soil quality due to poultry litter’s nutrient-rich organic matter composition. Integration of litter nutrients with corn production benefits poultry producers as a method of manure disposal and corn growers as a low cost fertilizer that is also beneficial to soil health in the long term. Although, research has shown corn production with poultry litter can exhibit economic gains and agronomic benefits over chemical fertilizer application, long-term land application of poultry litter raises agronomic and environmental concerns. Also, understanding grain production and soil characteristics resulting from long-term broiler litter amendment is important in establishing sustainable manure based corn production for the Kentucky karst region. Hence, the objective of this decade-long study was to quantify and compare corn grain production and resulting soil chemical properties when corn grain crop N requirement was provided fully with broiler litter, or in combination (1:1) with chemical fertilizer under no-till and conventional tillage systems. On average, broiler litter produced significantly higher grain yield than the mixture of litter and N fertilizer but similar to chemical fertilizer treatment alone. Long-term broiler litter application did not alter negatively soil chemical properties but had positive impact on soil physical and chemical properties. Results from this long-term study has a great impact on farmers' decision making with regard to poultry manure utilization as an alternate source of fertilizer for a sustainable crop production.
Technical Abstract: Use of broiler litter nutrients for crop production benefits crops, soils, and aids in disposing manure. Understanding corn (Zea mays L.) grain production and soil properties resulting from long-term poultry litter amendment helps establish a sustainable animal manure based corn production with low environmental risk potential. This decade-long study examined effects of supplying N requirement of corn grain crop by broiler litter alone, a 1:1 mixture of broiler litter and inorganic N fertilizer, and chemical N fertilizer alone on corn grain yield and post-harvest soil properties under no-till (NT) and conventional tillage (CT). The experimental design was split-plot which was replicated on four separate blocks. On average, broiler litter treatment produced significantly higher grain yield (10.1 Mg/ha) than the mixture of litter and N fertilizer treatment (9.6 Mg/ha), but similar to chemical fertilizer treatment alone (9.8 Mg/ha). The CT plots produced similar or greater grain yields than the NT. Broiler litter did not alter soil pH in broiler litter treatment and the mixed treatment (litter and fertilizer), but pH was decreased in the chemical fertilizer. The mixed treatment soils had greater cation exchange capacity (CEC), organic matter (OM), and total N (TN) (15.5 cmol/kg; 45 g/kg; 2.9 g/kg) contents than the mixed treatment (12.3 cmol/kg; 42.3 g/kg; 2.4 g/kg) and CF (10.1 cmol/kg; 35.5 g/kg; 1.7 g/kg). The soil P, Cu, and Zn increase in the broiler litter and the mixed treatments were not environmentally or agronomically significant. Tillage did not impact soil nutrient concentrations, but were slightly higher in the NT. Broiler litter nutrients under NT and CT offer an economical and environmentally safe corn production option. Long-term broiler litter application did not alter negatively soil chemical properties but had positive impact on soil physical and chemical properties. Results from this long-term study has a great impact on farmers' decision making with regard to poultry manure utilization as an alternate source of fertilizer for a sustainable crop production.