Phosphorous Leakage: 'food for thought'...

Phosphorous: a vital ingredient in fertilisers, which have become a necessity in food production.

Intensive agriculture has received bad press in recent years for its detrimental effects on the environment, and particularly on aquatic ecosystems. Eutrophication is becoming increasingly commonplace, causing severe environmental change across the globe. For a little reminder, take a peek at http://www.lakescientist.com/learn-about-lakes/water-quality/eutrophication.html.

The role of phosphorous in this process is a significant one, but the problem of phosphorous leakage from agricultural land into aquatic systems is double-edged. Firstly, the resulting eutrophication causes biodiversity loss and food web simplification, making the ecosystem more vulnerable to other forms of environmental change. But coupled with this is the issue of a growing population. Currently, food cannot be produced at current global levels without the use of artificial fertilisers, and with an estimated 2-2.5 billion new mouths to feed by 2050 our global demand for phosphorous will only increase.

But is there a way we can solve these two problems, in order to avoid further environmental change into the future? Some researchers seem to think so (http://www.agci.org/dB/PDFs/09S2_TCrews_StoryofP.pdf)!

Nearly 100% of the phosphorous eaten in food is excreted, which translates to 3 million tonnes of phosphorous lost down the toilets of the global population every year! So if this phosphorous is recovered and reused before it reaches aquatic systems, eutrophication can be significantly reduced. Moreover, recovery will reduce phosphorous wastage, helping to preserve finite reserves of rock phosphate – from which phosphorous for fertilisers is derived – that would otherwise be exhausted in the next 50 years or so.

So, if we save our wee we could save the world!

Of course, this won’t prevent leakage directly from agricultural land, and my personal opinion is that this is where we should focus in order to really address the problems of damaging environmental change in aquatic systems.