|Way, Thomas - Tom|
|Torbert, Henry - Allen|
|ARMSTRONG, SHALAMAR - Illinois State University|
Submitted to: Journal of Environmental Quality
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/24/2015
Publication Date: 11/6/2015
Publication URL: http://handle.nal.usda.gov/10113/62443
Citation: Watts, D.B., Way, T.R., Torbert III, H.A., Armstrong, S.D. 2015. Subsurface band application of poultry litter and its influence on phosphorus concentration and retention after runoff from permanent pastures. Journal of Environmental Quality. 44:1930-1937.
Interpretive Summary: A prototype implement has recently been developed at the USDA-ARS National Soil Dynamics Laboratory (NSDL) to subsurface band poultry litter. Subsurface applying poultry litter with this implement can potentially reduce the negative impact of P loss from agricultural fields to surface water runoff. Thus, a study was conducted to evaluate the retention of P in a Bermudagrass pasture following a high intensity surface water runoff event on soils from the Piedmont and Coastal Plains regions of the Southeastern US. Subsurface banding of poultry litter was compared to surface applied poultry litter, commercial fertilizer, and a non-fertilized control. Measurement of P in soil after runoff occurred showed that P was concentrated in the poultry litter bands. Lateral P movement from the poultry litter band was minimal. Concentrations of P 9.5 cm and 19 cm downslope of the banded area were similar to those observed in the control. Subsurface banding poultry litter also retained more P in soil compared to surface applying poultry litter and commercial fertilizer. This study shows that subsurface banding poultry litter in soil could be used as a management tool to retain P within the soil profile decreasing the potential for loss in surface water runoff.
Technical Abstract: Excessive P loss from agricultural fields has been identified as a major cause of eutrophication to river, lakes, and streams. To minimize and mitigate P loss from poultry litter (PL) applications, new technology is being developed for subsurface band application of litter below the soil surface. Thus, research was conducted to evaluate the impact of subsurface banding poultry litter on the retention of P in a pasture system. A 40 min runoff event was created using rainfall simulations in a bermudagrass (Cynodon dactylon L.) pasture on a common soil type from the Coastal Plain and Piedmont regions. The Coastal Plain soil type was a Marvyn loamy sand (fine-loamy, kaolinitic, thermic Typic Kanhapludults) and the Piedmont soil type was a Hard Labor loamy sand (fine, kaolinitic, thermic Oxyaquic Kanhapludults). Treatments consisted of surface- and subsurface-applied PL (bands 38 cm apart) at a rate of 9 Mg/ha, surface broadcast–applied commercial fertilizer (CF; urea and triple superphosphate blend) at the equivalent N (330 kg N /ha) and P (315 kg N/ha) content of PL, and a non-fertilized control. Measurements of total P, Mehlich 1 P, and water soluble P were measured at 0-5 and 5-10 cm depths to determine distribution and retention of nutrients following an intensive surface runoff event. The greatest P concentrations were observed in the shallow depth just below the soil surface. Phosphorus measurements taken at the locations of the poultry litter bands were greater than for the surface applied treatments and control. Nutrient concentrations in soil samples taken between bands of the subsurface applied poultry litter treatment were similar to the control. Subsurface banding poultry litter resulted in the greatest P retention compared to the surface applied poultry litter and commercial fertilizer treatments. Results obtained from this study show that subsurface band-applying poultry litter can increase the P retention in soil compared to surface broadcast application.