A.D. Harley & R.J. Gilkes
Rock-forming minerals of igneous and metamorphic rocks contain most of the nutrients required by higher plants for growth and development. Ground rock fertilisers may provide a source of nutrients to depleted topsoils where bulk soil solutions are not in equilibrium with fresh primary minerals. Slow dissolution rates of silicate minerals may inhibit the use of rock powders in agriculture unless suitable soils are identified and optimum rock powder properties developed. This review identifies previous research where the agronomic effectiveness of ground rock fertilisers has been evaluated. There are many ...
P. Hinsinger, M. D. A. Bolland, R. J. Gilkes
Soil samples were collected from 20 locations from the south western part of Western Australia and incubated at 25 °C for 60 days without or with finely ground granite powder at a rate of 20 g kg−1 soil, equivalent to about 20 t ha−1. Electrical conductivity and exchangeable Na, Ca and Mg were not significantly affected by granite application for most soils. Conversely, among the 20 soils studied, nine exhibited a significant increase in exchangeable K (atp