The Use of Ground Rocks in Laterite Systems: An improvement to the use of Conventional Soluble Fertilizers?

Othon H. Leonardos, W. Fyfe, B. Kronberg

ABSTRACT:

The geochemistry of lateritic terrains is discussed in terms of nutrient demand in agriculture. The data presented show a dramatic depletion of virtually all nutrients when compared to crustal levels and other soil systems. Increasing world demand for food production, particularly in tropical countries where alcohol production is also needed, has forced the agriculture frontier deep into lateritic areas. As cultivation is intensified the laterite becomes more barren and a neutral recipient for the massive doses of nutrients that are to be constantly added if production is to continue. Conventional soluble fertilizers such as NPK do not answer basic requirements. Designed for the high-nutrient and high-exchange-capacity soils of the northern hemisphere they are not held by the Fe2O3Al2O3SiO2H2O laterite systems and, under condition of excess rain, they can be wasted and consequently polluting. Furthermore, they do not supply a variety of both macro- and micronutrient elements that are normally present in soils in equilibrium with rock debris, but that are lacking in laterites. The replenishment of the laterite to the nutrient levels of natural fertile soils can be basically attained by adding into the system ground rocks of varied composition. The thermodynamical and geochemical background of this proposition is discussed and the state of the art is presented.

https://www.sciencedirect.com/science/article/abs/pii/0009254187901434