Residual Effects of Long-Term Tillage and Manure Application on Soil Macronutrients

Authors: Watts, Dexter; Torbert, Henry - Allen; Prior, Stephen - Steve

Submitted to: American Society of Agronomy Meetings
Publication Type: Abstract Only
Publication Acceptance Date: 11/4/2007
Publication Date: 11/4/2007
Citation: Watts, D.B., Torbert III, H.A., Prior, S.A. 2007. Residual Effects of Long-Term Tillage and Manure Application on Soil Macronutrients. American Society of Agronomy Meetings. CDROM.

Interpretive Summary:

Technical Abstract: Long-term tillage and manure application are thought to alter the soil nutrient status. Thus, a study was conducted to evaluate soil chemical properties after long-term tillage (>25 years) and manure application (> 10 years). Soil samples were collected at three depths (0-5, 5-10, and 10-20 cm) from continuous soybean and corn plots with and without manure managed under conventional (CT) and no-tillage (NT) at the Sand Mountain Substation in the Appalachian Plateau region of Northeast Alabama on a Hartselle fine sandy loam. The NT with manure resulted in a greater buildup of organic matter concentration (4.05 and 3.29 g kg-1) for corn and soybean plots followed by NT without manure (3.11 and 1.998 g kg-1) at the 0-5 cm depth, respectively; similar trend was shown for the cation exchange capacity (CEC). Further, the soil macronutrients (C, N, K, Mg, Ca, and P) were significantly higher at the 0-5 cm depth for NT and CT compared to other depths. Long-term manure application resulted in a greater concentration of macronutrients compared to adding no manure. The deeper depths contained a greater concentration of macronutrients under CT conditions relative to NT conditions, which is attributed to soil mixing in the plow layer. These results indicate that long-term tillage management plays an important role in the amount of plant nutrients retained in soil.