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Submitted to: Meeting Proceedings
Publication Type: Proceedings Publication Acceptance Date: 9/12/2010 Publication Date: 9/12/2010 Citation: Watts, D.B., Torbert III, H.A. 2010. Impact on Soil Utilizing Poultry Litter as a Fertilizer Source in Conservation Tillage Systems. In: Proceedings of the Uruguayan Society of Soil Science and ISTRO Uruguay Branch Conference, July 12-14, 2010, Colonia del Sacramento, Uruguay. p. 10. 2010 CDROM. Interpretive Summary: Long-term tillage and manure application are thought to alter soil’s ability to sequester plant nutrients and mineralize C and N. A laboratory incubation study was conducted to evaluate the impact of long-term poultry litter application (>10 years) as affected by tillage practice (>25 years) on soil fertility form a study area located at the Sand Mountain Substation in the Appalachian Plateau region of Northeast Alabama, USA. Results indicated that long-term tillage with PL application can increase soil C and N mineralization, nutrient retention, and organic matter. Technical Abstract: Long-term tillage and manure application are thought to alter soil’s ability to sequester plant nutrients and mineralize C and N. Thus, an aerobic laboratory incubation study (C and N mineralization) was conducted to evaluate the impact of long-term poultry litter (PL) application (>10 years) as affected by tillage practice (>25 years). Soil chemical properties were also evaluated to assess the influence of management practices on soil fertility. Soil samples were collected at three depths (0-5, 5-10, and 10-20 cm) from continuous soybean and corn systems managed under different tillage [conventional tillage (CT) and no-tillage (NT)] and fertility practices [poultry litter (PL) and inorganic fertilizer (IF)]. The study area was located at the Sand Mountain Substation in the Appalachian Plateau region of Northeast Alabama, USA, on a Hartselle fine sandy loam (fine-loamy, siliceous, subactive, thermic Typic Hapludults). Poultry litter addition and tillage both increased soil nutrients (N, P, K, Ca, and Mg). The greatest nutrient retention was at the 0-5 cm depth. This was a function of the NT system concentrating nutrients near the soil surface as opposed to a more even distribution seen under CT. The NT with PL (NT-PL) also had higher total organic carbon (TOC) concentration for corn and soybean (2.25 and 1.83 g C/kg) followed by NT with IF (NT-IF; 1.73 and 1.11 g C/kg), respectively. Furthermore, the C mineralized was significantly higher at the 0-5 cm depth for NT and CT compared to lower soil depths; similar patterns were observed for N mineralization. Long-term PL application resulted in higher C and N mineralization compared to IF. As depth increased, more C and N mineralization occurred under CT due to soil mixing in the plow layer. Results indicated that long-term tillage with PL application can increase soil C and N mineralization, nutrient retention, and organic matter |
