Benefits of Broiler Litter × Industrial By-Products Management Schemes in a Forage-Based System on Nutrients and Microbial Losses in Surface Runoff.

The inability to incorporate manure into permanent hayfield leads to  nutrients accumulation near the soil surface and potential for transport nutrient off site by runoff water. In this study, rainfall simulations were used to determine the effect of broiler litter (BL) treated with N and P immobilizing agents on nutrient losses from a bermudagrass (Cynodon doctylon) hayfield on  Marietta silt loam (Fine-loamy, siliceous, active, thermic Fluvaquentic Eutrudepts). The experimental design was a randomized complete block design with four treatments replicated three times. Treatments were no litter ( control),  13.4 Mg ha^-1  litter treated  with flue gas desulfurization (FGD) gypsum, and   with lignite at 20% (dry weight, wt/wt). Repeated rain was applied with a 3 day interval to determine how long FGD gypsum and lignite are effective in protecting  litter derived N, P and C from loss. Application of broiler litter substantially increased N, P and C concentrations in surface runoff as compared to the control (unfertilized). The addition of  FGD gypsum reduced P in runoff by 76%  as compared to broiler litter alone but was effective  only at the first rain event. Lignite did not  affect runoff P concentration, but significantly reduced runoff N by 60% as compared to  litter alone. The addition of FGD gypsum or lignite failed to significantly reduce microbial loads in runoff, though both reduced microbial levels by greater than 20%.Thus, broiler litter treated with FGD and lignite can be considered as a good management practice in mitigation of P and N and microbial levels in runoff, reduce water pollution and build healthy soil.