Submitted to: Agronomy Journal
Publication Type: Peer reviewed journal
Publication Acceptance Date: 6/3/2009
Publication Date: 8/18/2009
Citation: Adeli, A., Tewolde, H., Sistani, K.R., Rowe, D.E. 2009. Broiler Litter Fertilization and Cropping System Impacts on Soil Properties. Agronomy Journal. 101:1304-1310. Interpretive Summary: Improvement of soil quality in continuous cropping systems is critical to sustaining agricultural productivity. Since profit margins in monocropped cotton have declined due to high production costs and stagnant yields, there has been a renewed interest in producing cotton in rotation with corn which has resulted in increasing cotton yield as compared to continuous cotton systems. Crop rotation is also known to beneficially influence soil quality parameters. Increased cotton yield when rotated with corn is possibly related to the improvement of soil chemical, physical, and biological improvement. Recently, interest in using broiler litter N as an economical alternative source to commercial fertilizer for row crop production has increased. The beneficial effect of manure fertilization on soil properties such as organic C, microbial density and activity, soil aggregate stability and total soil porosity has been well documented, but mostly under monoculture systems. The combined effect of these two management strategies on nutrient cycling and soil properties is not documented in the southeast U.S., particularly in the Mississippi agro-ecosystem. Therefore, the objective of this study was to determine if rotating cotton with corn along with broiler litter fertilization has potential to sustain soil quality.
Technical Abstract: A 3-year study was conducted at the Mississippi Agricultural and Forestry Experiment Station, Verona, MS, in a Catalpa silty clay loam soil (Fine, smectitic, thermic Fluvaquentic Hapludolls) to evaluate soil chemical, physical, and biological changes resulting from cropping systems along with broiler litter applications. Three main plots with the sequence cotton-cotton-cotton, cotton-corn-cotton, and corn-cotton-cotton were split into five subplots each of which received 0, 4.5, 9.0, 13.5 Mg litter ha-1 yr-1, and commercial inorganic fertilizer N-P-K at the recommended rate as determined by Mississippi Soil Testing Laboratory. The fertilizer N source was urea-ammonium nitrate solution with 32% N that was injected into the soil at the rate of 123 kg N ha-1 yr-1 for cotton and 180 kg N ha-1 yr-1 for corn. Broiler litter fertilization had a greater impact on soil properties than crop rotation, the effect was most pronounced at 0- to 15-cm. Broiler litter application increased soil nutrient concentrations, reduced bulk density, increased soil total porosity and stability of the aggregates. Inclusion of corn into the rotation with cotton also increased total soil C, microbial biomass C, total soil porosity and stability of the aggregates by 10, 30, 11 and 19%, respectively, as compared to continuous cotton system, however, soil N, NO3-N, P, Cu and Zn concentrations reduced by 13, 14, 12, 23, and 22%, respectively. Inclusion of corn into the rotation with cotton plays a key role in improving soil physical and biological properties, but nutrient depletions, particularly N, in the soil after corn has to be taken into account for the following cotton crop.