IMPACT OF LONG-TERM TILLAGE AND CROP ROTATION ON CONCENTRATION OF SOIL PARTICULATE ORGANIC MATTER ASSOCIATED CARBON AND NITROGEN

The soil management practices may pose intense effects on the nature and properties of soils. A field experiment was conducted during 2002 to 2007 on a Vanmeter farm of the Ohio State University South Centers at Piketon Ohio, USA to assess the long term influence of tillage practices and crop rotation on soil particulate organic matter allied with carbon and nitrogen. Tillage treatments including conventional (CT) and No-till (NT) were factored into continuous corn (CC), corn-soybean (CS) and corn-soybean-wheat-cowpea (CSW) rotations by following randomized complete block design with 6 replications. The results of long-term study showed that 12 percent of significant increase was observed in the particulate organic matter (POM) in NT by the passage of time. The particulate organic carbon (POC) concentration under NT increased (15 %) significantly when CT converted in to NT over five year. Furthermore, particulate organic nitrogen (PON) increased (12%) significantly under NT than under CT. Crop rotation had significant effects on POM and the effects were more prominent in the CSW rotation. The POM, POC concentration increased with time in CC (11%) and CSW (15%) rotations. As soil depth increases, significant decrease was observed in POM, POC and PON concentrations regardless of tillage and crop rotation treatments. Tillage and crop rotation had no significant influence on the physical parameters; however, with time as a factor in the interaction significantly influenced the physical properties. Changes in the physical properties of the soil by tillage practices and crop rotation are mainly due to soil disturbance, placement, amount and type of added biomass crop in the soil ecosystem. Physical properties of soil facilitate microbial activities, support chemical functions, improve protection C and improve the quality of soil.