SGS Nutrient Theme: Environmental assessment of nutrient application to extensive pastures in the high rainfall zone of southern Australia

Abstract

To assess the risks and benefits of more intensive pasture management, 2 or 3 treatments with contrasting fertiliser regimes were selected from each site of the Sustainable Grazing Systems national experiment. The assessment used soil coring data, modelling and runoff nutrient concentration data. Soil acidification rates were estimated from the simulated nitrate leaching and product removal estimated from the stocking rates at each site. Much higher acidification rates were estimated at sites in Victoria and southern Western Australia than in northern New South Wales. This was because of a lower level of nitrate leaching in summer-dominant rainfall environments coupled with lower stocking ra..