Lime sales
Soil acidity is one of the few soil constraints, particularly subsurface constraints, that can be treated with appropriate management. There is increasing recognition amongst growers that lime use needs to increase and the trend in use is positive. However the current amount of lime used is only 50-65% of the estimated requirement of 2.5 million tonnes per year for the next 10 years to reach recommended pH targets (Figure 3).
Degradation of the soil resource has implications wider than the immediate concerns of production and profitability. Sustainability should also consider offsite impacts of soil acidity such as degradation of waterways (increased water run-off containing eroded sediment and nutrients), groundwater pollution (increased leaching of nutrients) and dryland salinity (reduced water usage).