Vegetable Production & Water Pollution On The Western Australian Coastal Plain
Amending pale sandy souls with 120t red mud/ha (freshly applied) increased the amount of fertiliser P held in the top 15 cm of soil, although the corresponding soil-test P levels at the beginning of the following crop were small, being only 5 to 10 ppm greater than on unamended soil. This is not sufficient soil-test P to allow soil-testing to be used effectively for the management of crops on amended soil, based on soil-test requirements on yellow Karrakatta sands. Another problem for soil-testing on red mud-amended soils in the short term is that the red mud cannot be mixed into the soil properly using field equipment, so that the soil-test measurement on a sample of soil is likely to be very variable. However, mixing may improve over time through repeated hoeing and the action of plant roots and water in breaking down aggregates of RMG.