Our Choice

Excerpt

As a boy growing up during the summers on my family's farm in Tennessee, I
learned from my father how to recognize the richest and most productive
soil: in a word, it's black. It's also porous and moist. But it was not
until much later in my life that I learned the reason fertile soil is black:
it's the carbon.
 
The soils of the earth contain between three and four and a half times as
much carbon-just in the first few feet-as do the plants and trees, and more
than twice as much as is currently in the atmosphere. With improved
agricultural and land management practices, we can significantly increase
the amount of CO2 that is pulled from the atmosphere by vegetation and left
sequestered in the soil, while enhancing agricultural productivity and food
security-and restoring degraded lands-at the same time. As with other
climate solutions, however, the success of this promising strategy depends
upon large-scale changes in long-established patterns.
 
When my father was a young man, the greatest threat to the productivity of
the land in America was soil erosion. Farmers and landowners in his
generation were enlisted by Franklin Delano Roosevelt in a nationwide
struggle to stop the soil erosion that had led to the Dust Bowl of the 1930s
and had left many farms cut with deep gullies, through which the best soils
for agriculture were washed away. To this day, I remember the lessons he
taught me. For example, when walking across the farm, keep an eye out for
the first hint of erosion; stop the beginning of a gulley before it can
start to deepen.
 
The battle against soil erosion and the degradation of soil quality on farms
in the United States is a success story. And by slowing soil erosion, the
U.S. has also begun to restore the carbon content of the soil. The crucial
layer of humus in healthy soils is made up, on average, of 58 percent
carbon. There are, however, new threats to the quality of soil and new
opportunities to sequester much more carbon in the soil.
 
More important, in much of the developing world-particularly in sub-Saharan
Africa-the degradation of soil quality continues to worsen and has reached
levels that threaten food security for hundreds of millions of people. The
loss of soil carbon in degraded African croplands has already exceeded the
magnitude of losses in the U.S. 80 years ago, just prior to the Dust Bowl.
Addressing this threat effectively can not only make African soils more
fertile and productive, it can simultaneously pull enormous amounts of CO2
from the atmosphere of the planet and sequester it in the soil as it is
restored to health.
 
From Our Choice by Al Gore
 
(c) 2009 Al Gore