Overuse leading to decline in world's phosphorus stock

Last Updated: Tue, Feb 15, 2011 11:40 hrs

A team of researchers has warned that overuse of phosphorus in the industrialized world may lead to global phosphorus stock getting depleted forever.

Stephen Carpenter of the University of Wisconsin-Madison and Elena Bennett of McGill University report that the human use of phosphorous, primarily in the industrialized world, is causing the widespread eutrophication of fresh surface water.There is a finite amount of phosphorous in the world. This is a material that's becoming more rare and we need to use it more efficiently," said Carpenter.

Excess phosphorous from fertilizer that washes from farms destroys freshwater ecosystems and degrades water quality.

"If you have too much phosphorous, you get eutrophication," warned Carpenter.

"Phosphorous stimulates the growth of algae and weeds near shore and some of the algae can contain cyanobacteria, which are toxic. You lose fish. You lose water quality for drinking."

The problem is complicated by the fact that that excess phosphorous in the environment is a problem primarily in the industrialized world, mainly Europe, North America and parts of Asia.

In other parts of the world, notably Africa and Australia, soils are phosphorous poor, creating a stark imbalance.

"Some soils have plenty of phosphorous, and some soils do not and you need to add phosphorous to grow crops on them. It's this patchiness that makes the problem tricky."

The researchers advise agricultural practices should be improved to better conserve phosphate within agricultural ecosystems are necessary to avert the widespread pollution of surface waters.

Phosphorous from parts of the world where the element is abundant, they say, can be moved to phosphorous deficient regions of the world by extracting phosphorous from manure, for example, using manure digesters.

The study appears in the Feb. 14 edition of the journal Environmental Research Letters. (ANI)