|Mays, D - ALABAMA A&M UNIVERSITY|
|Dawkins, R - AUBURN UNIVERSITY|
Submitted to: Journal of Sustainable Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 19, 2005
Publication Date: March 19, 2006
Citation: Sistani, K.R., Mays, D.A., Dawkins, R.A. Tall fescue fertilized with alum-treated and untreated broiler litter: runoff, soil, and plant nutrient content. Journal of Sustainable Agriculture. Vol 28(3):109-119 Interpretive Summary: The return of animal manure to land completes a natural recycling process. However, manure is also known to be a potential source of pollution to the environment. Increase in runoff phosphorus (P) and nitrogen (N) from pastures fertilized with poultry litter is well documented due to the environmental implications in many areas since these nutrients, particularly P, are the limiting factor for aquatic plant production. Reducing the concentration of these nutrients in runoff water will also reduce the risk of surface water contamination. It has been shown that aluminum sulfate commonly known as “alum” can greatly decrease P solubility in litter. The objectives of this research were (i) to study the effects of alum treatment of broiler litter on the yield and nutrient uptake of tall fescue and (ii) to investigate the effectiveness of different rate of alum addition to broiler litter on reducing the runoff P from litter treated tall fescue plots. Our study showed the P concentration in runoff water from tall fescue plots was reduced by 87% and also a greater plant concentration of N resulted from using alum-treated litter compared to untreated litter. It is imperative to manage manure properly, particularly when surface applied, in order to prevent manure P from being dissolved in rain water and carried to water bodies through runoff because most of the P in manure is in the water soluble form.
Technical Abstract: Surface and ground water quality may be impacted as a result of land application of poultry litter to pasture or crop lands. An experiment was conducted at Crossville, AL to study the effects of alum [Al2 (SO4)3,14H2O] treatment of broiler litter on the yield and nutrient uptake of tall fescue (Festuca arundinaceae) and the nutrient content of runoff water exited from treated plots. Alum was used at the rate of 0, 545 and 1090 kg per 1464 m2 of the poultry house. The low rate is the one recommended by Natural Resource Conservation Service (NRCS) in Alabama. Soil samples were collected from the research plots at the beginning of the experiment and at the end of each growing season from 0-7.5, 7.5-15, and 15-30 cm depth. Runoff samples were collected from each plot after each rainfall event that caused runoff. Alum treatments had no effect on tall fescue dry matter yield, and the herbage nutrient concentrations were within acceptable limits. We observed significant reductions in the runoff concentrations of NH4-N (28.6 mg/L for untreated litter VS 15.0 mg/L for alum-treated litter), total P (11.5 mg/L VS 5.1 mg/L), soluble reactive P (10.4 mg/L VS 4.7 mg/L), and particulate P (1.9 mg/L VS 0.8 mg/L). This practice should receive serious consideration as a method of reducing the adverse environmental impact of broiler chicken production when the litter is applied to pasture land.