News » How much could phosphorus use be reduced?

A theoretical optimisation model of agriculture, human diet, phosphorus use and recycling suggests that mineral phosphorus input could be reduced by 90%, assuming complete recycling of crop wastes, slaughterhouse waste phosphorus, animal manures and human excreta, no soil P accumulation and low soil P losses (compared to a ?baseline? situation based on current Netherlands data, with 60% of diet protein from animal sources, less than 50% of crop waste recycling and zero recycling of slaughterhouse waste and sewage phosphorus).

If phosphorus were fully recycled (including crop wastes, sewage, slaughterhouse wastes) a small amount of animal protein in the diet (around 10%) would result in the lowest mineral phosphorus consumption. In scenarios without full recycling of slaughterhouse waste, a vegan diet led to the lowest mineral phosphorus need. The lowest mineral phosphorus need per year is estimated at over 1 000 tonnes(P)/year for a population of 17 million people. ESPP NOTE: this would be 0.45 million tonnes P/year world mineral fertiliser use (7.7 billion population), compared to 16.5 - 22 MtP/y world fertiliser use (figures in Cordell 2014 and Hermann et al. 2018 above), with the assumptions above (e.g. no soil P accumulation).

For more information visit: ?Closing the phosphorus cycle in a food system: insights from a modelling exercise?, H. van Kernebeek, S. Oosting, M. van Ittersum, R. Ripoll-Bosch, I. de Boer, Animal, Volume 12, Issue 8, August 2018 , pp. 1755-1765 https://doi.org/10.1017/S1751731118001039