An investigation into the effect of soil compaction and tillage on plant growth and yield of winter barley(Hordeum vulgare L.)

Abstract

Abstract. The use of heavy machinery in agriculture is a major cause of compaction which, alters soil aggregate and pore structure affecting soil strength, porosity/availability of air and its response to heat. Compacted soils can lead to reductions in water and fertiliser uptakes leading to lower crop production and increased water runoff. Nutrient losses have been found to increase in compacted soil. A long-term 3x3 factorial Traffic (Random Traffic Farming, Controlled Traffic Farming and Low Ground Pressure systems) and Tillage (Deep, 250mm; Shallow, 100mm and no till) field trial at Harper Adams University, UK, was established in 2011. Initial results indicated benefits to crop yields from both Controlled Traffic Farming and Low Ground Pressure systems especially when applied under shallow tillage systems. An investigation was carried out in 2015 to determine whether the trial treatments had an effect on winter barley early growth and final yield by comparing components of yield at GS 30 and at harvest. Results for early growth found reductions in plant establishment and root dry mass for compacted areas possibly due to anaerobic conditions due to reduced soil pore size, however, the Barley yields were not significantly different (p>0.1). The compensation by the barley crop for the reduced plant numbers was by increased tiller survival and is thought to be due to the lower annual rainfall (22% reduction compared to the previous three year mean) especially during grain filling (33% reduction) which allowed sufficient soil moisture for optimum crop growth whilst sufficient soil pore air was maintained.