The US may be working for its future on foundations that are eroding. Science Alert notes that across the midwest US, one of the world's most active agricultural regions, experts observed that present soil erosion is around a thousand times faster than before modern agriculture took over.
Soil Erosion Acceleration
Science Alert notes how this is a remarkably greater soil loss than allowable.
Geologist Caroline Quarrier, one author of the study who participated in it as part of her master's dissertation, shared that this is the first time they know the natural erosion rates within the midwest. Quarrier also states that knowing the erosion rate prior to the settlement of Europeans and Americans, they can concretely assess how modern agriculture accounted for the massive acceleration of the process.
The recent study was included in the Geology journal. It was based on an element known as beryllium, which is quite rare. Quarrier and fellow researchers noticed the presence of this element in the uppermost soil of up to 14 prairies that are native, that are located throughout the Midwest, and that have been untouched by agriculture.
The said element is usually formed within the atmosphere of the earth. Its formation usually takes place as Milky Way cosmic rays pierce into the earth. When such rays touch the soil's topmost layer, the half-life may shed light on the rate of erosion that spans as far as thousands or even up to millions of years.
According to Phys, the team brought sample soil back into their labs. They then proceeded to sift the soil to sort the grains individually. The researchers also removed other particles that were not quartz and then ran the remaining sample through a purification procedure to isolate the beryllium.
The beryllium sample was then forwarded to another lab that counted each atom. The team then calculated erosion rates precisely, from the present up until the Ice Age that took place roughly 12,000 years before.
Science Alert notes that prior to the trend of modern agriculture, the average rate of erosion was around 0.04 mm each year in Minnesota, Iowa, South Dakota, Kansas, and Nebraska. This was the case around 12,000 years ago.
Moving on to the present-day, things have clearly changed.
According to Science Alert, the sustainability rules implemented by the USDA or US Department of Agriculture are based on the assumption that midwest upper soil can handle only one mm of soil erosion annually.
However, these findings show that the current soil erosion levels are much stronger than the typical erosion rates of pre-agriculture times. This shows that the tolerable rate of erosion is remarkably higher than the natural and actual erosion rates.
Such findings are worrying because they may lead to the soil's ultimate inability to recover. The soil may end up disappearing much faster than its accumulation rate.
Climate Change Implications
Soil plays a vital role in sucking out carbon from the atmosphere. With these great erosion rates, the effects of climate change may worsen.
On the bright side, there is still room and time to do something about this concern. With proper solutions, it is possible to lower the rates of erosion.
Check out more news and information on Climate Change in Science Times.