Soil erosion in caneland tillage systems

Soil erosion often limits the sustain ability of land for sugar cane production. Specifications of structural erosion control measures for cane land in Queensland have been developed by extrapolation from other crop types and areas, and by observation of structure performance within cane fields. Also the specifications did not take into account the adoption of reduced tillage and retention of crop residue, which reduce soil erosion. The WEPP (Water Erosion Prediction Project) model, was calibrated for rapid prediction of soil loss within structural soil conservation measures. For a 25 minute duration 10 year Average Recurrence Interval (ARI) design storm (52 mm), soil loss was predicted for five soils, for a range of cane furrow lengths and gradients, with different surface treatments. Soil erodibilities vary with soil and surface treatment and tillage results in higher erosion levels. Current specifications for soil conservation structural measures appear adequate for bare cultivated conditions and conservative where crop residues are retained, either through zero tillage or incorporation.