[ copied from http://news.discovery.com/earth/people-erode-soil-100-times-faster-than-nature-150114.htm ]
Jan 14, 2015 12:51 PM ET //
Cutting down or burning native forests and starting intensive agriculture – that is, industrial-scale farming, designed to produce high yields of crops and/or animals — can accelerate erosion dramatically, reports a newly-published study from researchers at the University of Vermont.
It causes so much damage, in fact, that in a few decades as much soil is lost as would naturally occur over thousands of years.
The researchers, who studied 10 large river basins in the southeastern United States, found that the damage started to occur hundreds of years ago, when large numbers of settlers arrived from Europe, and accelerated as agriculture developed. Before the 1700s, hillsides along the rivers eroded at a rate of about an inch each 2,500 years. But by the time erosion peaked in the late 1800s and early 1900s thanks to logging and tobacco and cotton cultivation, the hills were losing an inch every 25 years.
“Our study shows exactly how huge an effect European colonization and agriculture had on the landscape of North America,” says one of the researchers, Dylan Rood, “humans scraped off the soil more than 100 times faster than other natural processes.”
The study was published in the journal Geology.
The scientists came up with their findings by collecting sediment samples and then using an accelerator mass spectrometer at the Lawrence Livermore National Laboratory to help them measure the quantity of a rare isotope, beryllium-10, in quartz in the sediment. The isotope, formed by cosmic rays, builds up in the top of soil. As the erosion rate increases, the soil accumulates less beryllium-10.
Scientists say that across the planet, erosion by water and wind is as dire of a threat as climate change, which actually adds to the loss of soil. A 2006 study by Cornell University researchers reported that around the world, soil is being swept and washed away 10 to 40 times faster than it can be replenished by natural processes. As a result, the planet is losing a quantity of cropland equal in size to the state of Indiana each year. Back in the 1930s, drought and poor farming methods caused a period of severe dust storms called the Dust Bowl, which caused an economic catastrophe for farmers.
Now this is a news story I wish we were hearing more about… but who cares about dirt, right?
That’s the problem. Who cares about compost?
Compost is a huge part of the answer here, as it restores soil and helps prevent erosion.
I really, really hope that by the time I’m super old that humans are embarrassed of their past with landfills.
We’re completely out of tune.
If you want to take a major step in the right direction, start composting.