Sustainability of phosphorus fertilisation: sources and forms of phosphate

Phosphorus (P), which originates from a non-renewable natural resource, is essential for crop productivity, food security and human health. Despite being a finite resource its use has been increasing consistently over the last few decades. The major use of the phosphate rock is the manufacture of P fertiliser, agriculture also being the main source for nonpoint source P pollution, which causes the eutrophication of water bodies. Thus, there is great need for a sustainable use of P with special attention to agricultural use, namely P fertilisation. This paper explores P sources and forms that could be phytoavailable and hence used as fertilisers. Current trends in phosphorus fertilisation are also discussed with a focus on approaches to net decrease in phosphate rock exploitation and closure of phosphorous cycle use.