Review and outlook for agromineral research in agriculture and climate mitigation

Abstract

Agrominerals are finely ground rocks and minerals used as low-cost fertilisers, and they have received more attention in recent years as sustainable development and climate change mitigation have come to the forefront of societal concerns. Here, we summarise progress in agromineral research over the last 20 years, and discuss the challenges and opportunities of this discipline. The idea of agrominerals has been around since the early 19th century. However, widespread application is subject to economic practicality. In recent years, two big trends have dominated agromineral research. First, some global warming mitigation strategies, such as ‘enhanced chemical weathering’ and bio-energy carbon capture and storage call for the application of rock powders in arable land on a massive scale. This gives agromineral research an urgency and significance. Second, advances in knowledge of mineral weathering kinetics are poised to transform predictions of agronomic effectiveness from mere empirical studies to more quantitative evaluation. We now have a much better understanding of the factors that influence weathering and nutrient release rates. We forecast that rapid advances in some areas of biogeochemistry will enable advances in the study of agrominerals. In particular, we will be able to measure weathering and nutrient release rates at the field scale, and ultimately to predict kinetic processes of mineral dissolution or precipitation in soil–water–plant systems and the cycling of nutrients and toxic elements in agricultural land.