BENEFICIAL EFFECTS OF SHALLOW WATER TABLES: EVOLUTION OF AN IRRIGATION TRIAL

Fresh shallow water tables can contribute positively towards crop production by increasing soil moisture in the root zone. However, few Australian sugar growers consciously reduce their irrigation rates to take advantage of this valuable resource. In a field trial at Bundaberg, crop response to irrigation was measured when a shallow water table was situated between 1 and 1.2 metres below the soil’s surface. Under these conditions, the water table provided approximately 23% of the crop’s evapotranspiration. In addition, crop responses showed that irrigation might be unnecessary when the water table is within one metre of the soil’s surface.