2017 Roberts Global P and K Use and Balance in World Agriculture
Phosphorus (P) and potassium (K) fertiliser use in the world varies in space and time. Several factors such as weather, policies, economic considerations etc. are drivers of such variability. Use of fertiliser nutrients in crops and their offtake from farms, at local, regional or continental scale, influence crop yield, farm profitability, and the sustainability of production systems. Careful assessment of nutrient balances, the difference between nutrient additions and removals at different scales, indicates the merits of current practices, and provides guidance whether optimization is required in plant nutrient management. The present article illustrates the P and K fertiliser use in intensive production areas of the world, how that has influenced farm-gate balances of these major nutrients, and the impact on native fertility, crop productivity and economics of production.