Vegetation type, soil type and shifts and cycles in climate affect deep drainage in eastern Australia

Abstract: Secondary dryland salinity is usually caused by clearing native vegetation and introducing crops and pastures. This damages landscapes and costs more than $1,000 million annually in agricultural production alone. However, in some areas the rate of increase has slowed or there has been a decrease in the extent of dryland salinity. To understand the dynamics of the hydrologic balance in eastern Australia, the HowLeaky?2008 model was used to simulate a range of soil types, climates and vegetation systems. Four soil types were simulated: (i) a Kandosol with plant-available water capacity (PAWC, to 1200mm depth) of