Traditional ploughing irreparably depleting soil cover

Traditional plough-based agriculture combined with the growing demands of a burgeoning population for more food production, is fast depleting the Earths soil supply.

Washington, Aug 9 : Traditional plough-based agriculture combined with the growing demands of a burgeoning population for more food production, is fast depleting the Earth's soil supply.

Prof. David Montgomery from the University of Washington Earth and space sciences, has in his study said that long-established practices has been found to increase soil erosion to the point that it is not offset by soil creation.

No-till agriculture, in which crop stubble is mixed with the top layer of soil using a method called disking, is far more sustainable, he said.

"Soil loss through conventional agriculture is in a range of 10 to 100 times greater than the rate at which soil is created. No-till agriculture brings it into the ballpark, surprisingly close to being balanced with soil creation," he added.

As part of his study, Prof. Montgomery looked at data from more than 1,650 measurements published in more than 200 studies examining various aspects of farming practices, soil creation and erosion.

He found that long-term erosion rates worldwide averaged less than one-tenth of a millimetre per year, which was similar to the rate at which soil was produced through mechanical, chemical and biological processes that dissolved rock and mixed the grains with organic matter.

Erosion rates consistently exceeded one millimetre a year - less than a half-inch per decade - only in steep alpine terrain, while ploughed fields eroded at about the same pace as the Himalayas.

The findings appear in this week's online edition of the Proceedings of the National Academy of Sciences (PNAS).

ANI