Effect of Soil Type and Operational Speed on Performance of Some Selected Agricultural Field Machinery in South East Nigeria

Abstract

Abstract: A research was conducted to examine the effect of soil type and operational speed on the performance of some selected agricultural field machineries in South- East Nigeria. Results revealed that the disc plough had maximum field efficiency of 88.11% at a working speed of 6kmhr^-1 in clay-loam soil, while in sandy-clay soil; it recorded maximum field efficiency of 87.98% under the same operational speed (6kmhr^-1) and in loamy-sandy soil it obtained  maximum field efficiency of 87.55% at the speed of 5kmhr^-1. The harrow had maximum field efficiency of 98.54% at operational speed of 9kmhr^-1 in sandy-clay soil; in clay-loam soil at a working speed of 8kmhr^-1, it recorded maximum field efficiencies of 87.98%, and 87.19% respectively. Results further indicated that the ridger had maximum field efficiencies of 89.09%, 87.96% and 87.95% respectively, in sandy-clay, clay-loam and loamy-sandy soil under operational speed of 9kmhr^-1. At this same working speed, the rotovator obtained maximum field efficiencies of 89.81%, 89.40% and 87.11% in clay-loam, sandy-clay and loamy-sandy soil respectively. On the other hand, the planter recorded its maximum field efficiency of 89.69% in sandy-clay soil at speed of 5kmhr^-1, while in clay-loam soil, it had maximum efficiency of 89.30% at speed of 6kmhr^-1 and in loamy-sandy soil, and it achieved a field efficiency of 88.99% under working speed of 7kmhr^-1. The harrow, ridger and rotovator attained maximum field efficiency at higher operational speeds (8 – 9kmhr^-1) as compared to plough and planter that achieved their maximum field efficiencies at lower operational speeds (5 – 7kmhr^-1). The lower operational speed of the plough was attributed to the higher tractive and draft force required in its operation, to initially break up and turn over the compacted soil which is associated with slow operational speed than other tillage implements; while that of the planter was attributed to the high precision required in its operation for proper metering, placement and covering of the seeds to avoid damages, which could only be achieved in a moderately slow working speed. Finally, the average efficiencies for all the implements were highest in sandy-clay soil, followed by clay-loam soil and least was obtained in loamy-sandy soil. The variation in the performances of the various implements could be attributed to the differences in soil physical and mechanical properties and/or demographic factors that exist among different soil types in different agro-ecological areas of South-East Nigeria.