Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: March 29, 2012
Publication Date: June 27, 2012
Citation: Read, J.J., McLaughlin, M.R., Adeli, A. 2012. Rainfall simulation to evaluate nutrient loss from Marietta soil amended with poultry and cattle manures. Proceedings Mississippi Water Resources Conference. http://www.wrri.msstate.edu/publications.asp. Technical Abstract: Broiler litter, a mixture of manure and bedding materials, is a major waste product of the broiler chicken industry and is often used as a fertilizer for pasture and hay crops. Of the total land area in Mississippi, approximately 474,000 ha are utilized for grazing by livestock, which constitutes another source of manure nutrients. The build-up of N and P at the soil surface (0- to 15 cm) increases the potential for degradation of surface and groundwater resources, but the ultimate fate of these manure nutrients is not completely understood. This paper presents results of a rainfall-simulation study conducted in the greenhouse using eight PVC troughs (each 0.08 m deep x 0.18 m wide x 1.45 m long) filled with sod of common bermudagrass collected from a Marietta loam soil. The objective was to determine if the combination of broiler litter and cattle feces (dung) increases the nutrient load in surface-water runoff, as compared to litter alone. Treatments comprised 130 g litter (~3925 mg N) to six troughs, 26 g dung (~52 mg N) to four of these six; and two untreated ‘controls’. The volume and nutrient concentration of leachate was determined for five ‘events’ with a rainfall intensity of 75 mm h-1. Results indicated total N loads of 64, 366, and 378 mg in the control, broiler litter, and litter + dung treatments, respectively. Based on total N applied, these N loads correspond to N-leaching losses of 9.3% for troughs with litter and 9.5% for troughs with litter + dung. Approximately 40 to 70% of the N applied was recovered in leachate during the first rainfall event; NH4 was the predominant inorganic constituent in leachate. Because the quantity of leachate N was similar in litter and litter + dung treatments, grazing by cattle is not expected to contribute significantly to the N loss in runoff from pasture fertilized with 4.98 Mg broiler litter ha-1 (2.22 tons/acre). Results will be discussed in relation to managing bermudagrass, broiler litter, and livestock on Marrieta soil to decrease watershed runoff losses of N and P.