Using Meta-Analyses to Assess Pedo-Variability Under Different Land Management.

Using Meta-Analyses to assess pedo-variability under different land management

Vincent d. Obade, Carbon Management and Sequestration Center (C-MASC), Ohio State University, Columbus, OH and Rattan Lal, School of Environment and Natural Resources - The Ohio State University, Columbus, OH

Abstract

The conflicting spatial and temporal information on the impacts of management on soil quality creates the need for a comprehensive approach that can combine soil property data into a single accurate value.  This study demonstrates an application of meta-analytic methods to integrate and quantitatively describe the effects of management practices on soil physical and chemical properties influencing agronomic yields.  Soil samples were obtained from 5 sites within Ohio, USA at similar landscape position but different management practices.  Soil samples were analyzed for determination of total soil organic carbon (SOC), bulk density (ρ_b), available water capacity (AWC), electrical conductivity (EC), and pH.  Data were compared using the Odds Ratio (OR).  Results indicate that the soil under conventional tillage (CT) had a lower OR (0.57) than that under no-till (NT) for SOC, pH (OR=0.81), ρ_b (OR=0.84), and AWC (OR=0.69).  However, the OR for EC was the reverse (OR=1.36), being higher in soil under CT than NT.  Based on the meta-analyses which provide a comparative assessment within the whole profile, the data support the conclusion that soils under CT are of a relatively lower quality than those under NT because they have lower SOC and AWC, but higher EC or salinity. Soil data under on-farm conditions will be collected over subsequent years, and analyzed in a similar fashion.  Agricultural production may benefit from decision tools that help identify the most sustainable management practices.