Soil Compaction Due to Mechanical Harvesting in Wet Soil

摘要

The Cauca Valley of Colombia is a semi-humid region with mostly fine textured soils, on which cane is planted and harvested all year round; therefore, compaction problems and direct cane stool damage may arise during mechanical harvesting operations.The present study was undertaken to quantify cane field damage caused by mechanical harvesting equipment under wet soil conditions. A field planted to variety MZC 74275 on a Mollisol (clay loam) was harvested after a 50 mm rainfall event. The controlledand combined traffic of a fully mechanical harvesting system was compared with the traffic of a semi-mechanised harvesting system. A zero traffic treatment, where the cane was manually cut and removed from the plot by hand, was included as reference. A nearby commercial plot was mechanically harvested without traffic supervision. Results showed that direct stool damage by infield machinery is reduced to a minimum when cane fields are planted at 1.75 m row spacing, and compaction is limited to the top 0.25 m soil depth. Current ratooning practices, including one pass of a double-shank sub-soiler, were sufficient to restore soil physical properties. The cane yield of plots under controlled traffic of mechanical harvesting equipment resulted in similar cane yields to the plots without infield traffic. Uncontrolled traffic of mechanical and semi-mechanical commercial harvesting induced a cane yield loss of 30 t/ha as a result of increased stool damage. Controlled traffic of infield machinery is thus important to sustain production in any harvesting system under the soil and climatic conditions of the Cauca Valley in Colombia.