Global Nutrient Overload?

posted 26 April 2001

An article in a recent issue of Science reported that if trends of fertilizer consumption from the past 35 years are projected, there would be 2.7 times as much nitrogen used in 2050 as at present, and 2.4 times as much phosphorus. The article went on to forecast that this increased nutrient use would drive an identical increase in eutrophication (nutrient enrichment) of the world's ecosystems, resulting in habitat destruction and species extinctions… loss of biodiversity.

Biodiversity is important, and we share the concern. But will the projected scenario really happen? Here's why it shouldn't.

The authors of the Science report made a mistake in projecting the fertilizer trend. They assumed that global use of fertilizer would continue to increase without slowing, as shown by the line marked "L" in the figure below. Actually, world consumption figures for phosphorus already show a distinct slowing in growth rate, so the curves "E" and "Q" could also be considered projections. In reality, projecting 50 years into the future using the past 35 years is simply impossible.

The world today (excluding the former Soviet Union) produces 25 percent more crop per unit of phosphorus fertilizer applied than it did twenty years ago. Simply put, farmers are improving their nutrient use efficiency. We anticipate this will continue, through continuing research, adaptation and innovation.

For more details on the criticism of the forecast of phosphorus consumption, please see the full letter to the Editor of Science, below:




At a National Nutrients Workshop held 19-20 March in Ottawa, Canada, PPIC Director Tom Bruulsema, working together with Dave Finlayson of the Canadian Fertilizer Institute, made a presentation to communicate industry's commitment to solving problems related to the environment and human health. The workshop, attended by 90 people from federal and provincial natural resource related departments and other interested parties, was held to discuss the conclusions of a recent scientific assessment on nutrient impacts on the environment, and to identify opportunities for action.


For a copy of the presentation, "Fertilizer Industry Initiatives in Nutrient Management", click on the icon below: