Submitted to: Journal of Soil and Water Conservation
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/8/2000
Publication Date: 3/1/2001
Citation: POTE, D.H., REED, B.A., DANIEL, T.C., NICHOLS, D.J., MOORE JR, P.A., EDWARDS, D.R., FORMICA, S. 2001. WATER-QUALITY EFFECTS ON INFILTRATION RATE AND MANURE APPLICATION RATE FOR SOILS RECEIVING SWINE MANURE. JOURNAL OF SOIL AND WATER CONSERVATION. 56(1):32-37.
Interpretive Summary: High nutrient levels in surface runoff from intensive animal production areas often promote excessive algae growth in streams and lakes, and lead to serious water-quality problems. Expansion of confined swine production in some regions of the United States has raised concerns that swine manure applications may threaten water quality in those areas. For example, increasing swine production in the Buffalo National River watershed is believed to be partly responsible for declining water quality in that scenic national park. Swine manure is usually surface applied to pastures and hay fields, but better management of manure applications may be required to adequately protect water quality. Therefore, research is needed to help identify the best sites and methods for manure applications. This research found that concentrations and mass losses of water-soluble nutrients in storm runoff from pasture increased significantly following swine manure applications, and doubled when manure application doubled. Infiltration rate (the rate at which rain soaks into a soil) ranged from 0.3 to 2.4 inches per hour. Soils that had a high infiltration rate produced less storm runoff (as expected), but also had lower concentrations of the soluble nutrients in storm runoff. Concentrations of nitrate and ammonia at the 16-inch depth in the soil did not increase following swine manure applications. Nutrient loss in runoff from manure applications can be a serious threat to water quality, but information from this research can help agricultural producers make better manure management decisions to protect water quality while maintaining high levels of production.
Technical Abstract: We investigated effects of rain infiltration rate and manure application rate on quality of leachate and runoff from four soils receiving applications of swine (Sus scrofa L.) manure slurry. Tall fescue (Festuca arundinacea Schreber) plots received 1 or 2 Mg (dry weight) ha-1 of swine manure slurry to provide 78.4 or 156.8 kg N ha-1. Simulated rain (75 mm h-1), applied 24 h after slurry application, produced 30 min of runoff from each plot. Mean infiltration rates ranged from 7.7 to 60.6 mm h-1. Concentrations and mass losses of total Kjeldahl nitrogen (TKN), NH4-N, dissolved reactive P (DRP), and total P in runoff increased significantly (à=0.05) following slurry applications, and doubled when slurry application doubled. High infiltration rates reduced runoff volumes and runoff concentrations of soluble nutrients: Cl, total dissolved solids, DRP, TKN, and NH4-N. Concentrations of NO3-N and NH4-N in leachate water, collected at 0.4-m depth by suction cup lysimeters, did not increase following slurry applications.