Effect of Conventional & Conservation Tillage on compaction in Namibia

High compaction in conventional tillage (CV) systems results in lower root growth. Studies were conducted at Ogongo, University of Namibia to compare the effects of two CV treatments (i.e. tractor - drawn disc harrow (TDH) and animal - drawn mouldboard plough (AMP) and two Namibia Specific Conservation Tillage (NSCT) (tractor - drawn ripper furrower (TRF) and animal - drawn ripper furrowers (ARF) on soil compaction. The study showed significant (p<0.001) differences in mean penetration resistance (PR) among the tillage methods in the two years and a significant positive linear relationship between penetration resistance (PR) and depth in 2012 at planting and at harvesting for various depths for the four tillage methods (p<0.001). PR increased with depth across all four tillage methods at planting and harvesting for 2011 and 2012. The farmers’ fields, 31% (n=13) had PR values that are less than 2 MPa. All NSCT methods resulted in lower PR than the CV methods showing that the NSCT methods contributed to better reduction in soil compaction. Therefore NSCT has the potential to transform Namibian smallholder agriculture into a sustainable and productive crop production strategy.