Healthy Soils Can Help Reverse GLOBAL WARMING
Healthy soils store huge quantities of carbon. Cutting emissions is important but even successful reductions will not reverse the high levels of carbon already in the atmosphere. Fortunately for the planet, we can reverse global warming by restoring drylands and desertified soils to health so they can capture and sequester large amounts of carbon. Soils rebound quickly but governments and individuals need to act rapidly and globally to ensure success.
The time is running out so we must act NOW.
The math is simple. Human activity over the past 200 years has turned huge swaths of Earth’s grasslands and
swamplands into degraded and desertified soils and, according to Rattan Lal (2004), has led to the loss of between 50
and 66% of historic soil carbon. Restoring health to agricultural soils, grasslands and swamplands could recapture much of this carbon. “The technical potential of carbon sequestration in world soils Maybe 2 billion to 3 billion metric tons per year for the next 50 years”.
1. Which is the equivalent to ½ to ¾ of the total carbon added annually to the atmosphere?
2. Industrial agricultural practices are the main source of CO2 emissions. Farming techniques created over 200 years ago have changed little: till the soil, plant, fertilize (now with chemicals), grow, reap and then leave soil exposed to the elements until next spring. From 1850 to 1970, “ twice as much atmospheric carbon dioxide has
derived from farming practices as from the burning of fossil fuels … .”
3. After 1970, fossil fuels emitted more but the level of emissions from agriculture did not decrease. I.e., emissions from burning fossil fuels exceeded that from soils.
Leaving soils exposed to the elements and the application of chemical fertilizers and herbicides kill the earthworms,
microbes, and bacteria that form the lifeblood of healthy soil. Unhealthy soils quickly lose carbon and moisture and topsoil turns to windblown dust or is washed into streams and rivers. “In the past 150 years, between 50 and 80
percent of organic carbon in the topsoil has gone airborne.”
4. And “[g]lobally, each year some seventy-five billion tons of soil is lost. That would cover about thirty-eight thousand square miles of arable land, an expanse larger than the nation of Australia. … In the United States, Cornell soil scientist David Pimentel says that 90 percent of our cropland
is losing soil to wind and water erosion at thirteen times the rate that soils are being formed.”
5. Better soil management practices can stop this loss