What have you done today to lower your impact?

We are washing away the foundations of our existence on every front. It is high time we move from crashing about on the planet like a bull in china shop and find a way to go forward with intent. We must find systems of living based on sustainability. The systems and tools exist, it is up to each of us to adopt them.

Blog Archive

Friday 29 February 2008

Food part 1 - Soil erosion - by Robb

There are many issues surrounding food, it’s production, transportation, and consumption. I’ve already touched on some issues relating to corn production in the previous post. I’d like to go right back to the basic ingredients for production of healthy food; clean water, clean air and rich healthy soil. I’ll deal with more with clean water in later posts and clean air will require many posts as well. For now I’d like to start with soil.

Our entire civilization depends on our soil!


“Around the world, soil is being swept and washed away 10 to 40 times faster than it is being replenished, destroying cropland the size of Indiana every year....” reports a Cornell University study by ecologist David Pimental.

The same Cornell report points out that 99.7 percent of human food comes from cropland. Cropland is shrinking by almost 37,000 square miles a year due to soil erosion.

"Erosion is one of those problems that nickels and dimes you to death: One rainstorm can wash away 1 mm (.04 inches) of dirt. It doesn't sound like much, but when you consider a hectare (2.5 acres), it would take 13 tons of topsoil -- or 20 years if left to natural processes -- to replace that loss," Pimentel said.

If that isn’t enough to scare you here are some more stats from that report:
* The United States is losing soil 10 times faster -- and China and India are losing soil 30 to 40 times faster -- than the natural replenishment rate.
* The economic impact of soil erosion in the United States costs the nation about $37.6 billion each year in productivity losses. Damage from soil erosion worldwide is estimated to be $400 billion per year.
* As a result of erosion over the past 40 years, 30 percent of the world's arable land has become unproductive.
(http://www.news.cornell.edu/stories/March06/soil.erosion.threat.ssl.html Feb 2008)

So what’s going on? It seems clear we need to look carefully at farming methods. It is well known that tropical rainforests exist over very poor soils due to their amazing ability to very quickly recycle nutrients. So when these forests are cleared for farming or livestock the soil can only support a few years of crops before erosion washes it away. Stopping the clearing of tropical rainforests make sense on so many levels that it is frankly unbelievable that it continues.

Industrial farming methods are equally to blame. At every planting season the earth is laid bare to dry out and blow away. It is already weakened through overfarming and chemical usage and lack of organic matter to bind it together and hold moisture. According to Pimental in just one winter almost 2 inches per hectare (2.5 acres) of soil blew away from cropland in Kansas, the equivalent of 650 tons of topsoil per hectare. There is new evidence suggesting that the increasing dustiness of the US west has gotten much worse in the last 200 years and is due largely to intensive livestock grazing and railroad building. (http://www.livescience.com/environment/080225-west-dustier.html March 2008)

Low or no tillage farming is proving to substantially reduce erosion. Avoiding the plough and leaving mulch in the soil, even if only 20%, reduces erosion by 70% to 80% according to conservation agriculture trials monitored by the Catholic University of Leuven in Belgium. (http://news.bbc.co.uk/2/hi/europe/5274100.stm Feb 2008)

So what can an individual do about this? As with most efforts to live in a sustainable manner one begins with detailed examination of personal consumption. Where does your food come from? Does it contribute to irresponsible farming practices? Are all the calories you are consuming full of quality nutrition? The easiest solution is to grow your own food and drastically reduce meat consumption. By growing as much food as you can, organically, you can offset the food with unknown origination with food you know everything about. But if you can’t grow it, buy it. Organically grown food is much kinder to the soil as it depends on healthy soil for it’s production rather than on chemical fertilizers, herbicides, and pesticides. Buy supporting organic farming you will be encouraging conservation of the soil and getting healthier food in the bargain, a much more sustainable choice.

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