Hydrologic effects of crop residue management practices

Abstract

A daily water balance model of catchment behaviour was used with rainfall and runoff data from three 1 ha catchments over the period 1976-1981 inclusive to study the effects of different practices of crop residue management on volumes and peak rates of runoff. The practices studied were stubble burning, stubble incorporation, and stubble mulching. Rainfall and runoff data from the six-year study period were used to calibrate the catchment model to each of the management practices in turn. A 64-year record of daily rainfalls from a nearby meteorological station was used to estimate the long-term effects of the practices on the frequency distributions of runoff. An empirical relationship between peak rates of runoff and daily amounts of runoff was used with the daily water balance model to estimate the effects of the practices on peak rates of runoff. Burning of stubble produced the highest peak rates and amounts of runoff and mulching the lowest.