(This is Part 7 of a continuing series. Go back to Part 6.)
The foundation of civilization itself is a thin layer of topsoil covering much of the landmass of the earth. This layer of topsoil was geological eons in the making, and now it is rapidly being lost.
The U.S. is losing about 2 billion tons of topsoil a year. India is thought to be losing about 4.7 billion tons per year. China is losing much more. And virtually every other country on earth is losing precious topsoil. Why is this happening?
Take the case of China. In the last half-century China's herds of cattle, sheep and goats have tripled to 400 million. For the most part, they graze on grasslands in northern and western China. And they are literally denuding the soil.
To retain topsoil it must be covered by vegetation. Without vegetation, topsoil becomes vulnerable to wind and rain storms and blows or washes away.
As topsoil is depleted, what is left underneath is sand, which cannot support crops. Thus the loss of topsoil eventually leads to desertification, that is, the process of the encroachment of desert upon the earth's landmass.
Scientists says that the entire northwest area of China is turning into a desert on a scale never before seen. There are vast deserts in that area already and they are linking up. Indeed, the Gobi desert has expanded to within 150 miles of the capital itself, Beijing.
And it's not just China. The huge Sahara desert in North Africa is encroaching rapidly upon the countries to its north and south. The large southwestern part of the United States is also becoming drier year by year. Huge swaths of Asia and Africa—holding two-thirds of the world's people—are undergoing desertification, but it's occurring to some degree across the globe.
Denuding of the soil is basically caused by three things:
Overcutting of trees and forests, overgrazing by livestock and overplowing of farmland.
Demand for humanity's food staple, grain, has tripled in the last 50 years. To meet this need, immense forests and savannahs have been cleared to create farmland. However this process is coming to a close because, on a relative basis, there just isn't much left of either to clear.
Thus in the future the existence of sufficient farmland to meet humanity's needs will come down to preservation of existing land. To do this, tremendous emphasis will need to be put on keeping existing land covered with vegetation so that topsoil can be preserved.
(This is the end of Part 7. Go to Part 8.)
—jim sloman, 9.21.04 for Apr 21
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