Subsurface banding of poultrylitter influence on runoff nutrient losses ina no-tillage maize cropping system

Authors: Watts, Dexter; Way, Thomas - Tom

Submitted to: Soil & Tillage Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/13/2019
Publication Date: 7/20/2019
Citation: Watts, D.B., Way, T.R. 2019. Subsurface banding of poultrylitter influence on runoff nutrient losses ina no-tillage maize cropping system. Soil & Tillage Research. 194:104345. https://doi.org/10.1016/j.still.2019.104325.
DOI: https://doi.org/10.1016/j.still.2019.104325

Interpretive Summary: Technology has recently been developed at the USDA-ARS National Soil Dynamics Laboratory (NSDL) to subsurface band apply poultry litter in soil. A study was conducted to evaluate the influence of using this technology in a corn cropping system on N and P losses. Subsurface banding of poultry litter was compared to surface applied poultry litter, surface banding of poultry litter, inorganic fertilizer, and a nonfertilized control. Artificial rainfall was created using a rainfall simulator to generate surface water runoff. The standard practice, surface broadcasting of poultry litter, resulted in the greatest N and P losses with surface water runoff. Placing poultry litter in bands 3-5 cm below the soil surface using a new prototype implement developed at the NSDL reduced N and P losses to those observed with the nonfertilized control. This study shows that subsurface banding of poultry litter in soil can reduce N and P losses compared to the traditional fertilization practices.

Technical Abstract: Poultry litter (PL) is often used as an alternative nutrient source for crop production in the southeastern U.S. Historically, PL has been broadcast applied on the soil surface, leaving the nutrients susceptible to runoff. Developments made in recent years allow for placing PL in narrow bands below the soil surface with minimal disturbance. This technological advancement could potentially reduce the transport of P in surface water runoff from fields managed under conservation agricultural systems. Thus, a study was conducted at the Piedmont Agricultural Research Unit located in Camp Hill AL, USA to evaluate the influence of banding PL into a no-till field on P loss. Treatments consisted of surface banded PL, subsurface banded PL (3-5 cm below the surface), broadcasted PL, broadcasted commercial fertilizer (CF) and a nonfertilized control. Runoff events (40 min) were created using rainfall simulations. The PL treatments were applied based on an N rate of 168 kg total N ha-1. For the CF, inorganic N was applied at a rate of 168 kg total N ha-1 and P at a rate of 45 kg P ha-1. The greatest losses of dissolved P and inorganic N occurred with the surface broadcast treatments. Subsurface band applying the PL reduced P concentration losses and loading in surface water runoff to levels of the control. No differences were observed in runoff volume between treatments. Thus, total P losses mimic those observed for dissolved P concentration and loads. Approximately 60-80% of the total P concentration was dissolved reactive P regardless of application method. Subsurface band application reduced total P concentration by 95% when compared to surface broadcasted litter. These results show that subsurface band-applied PL can greatly reduce the impact of P loss to the environment when compared to conventional surface-applied PL and CF practices.