Fertile Soil Disappearing on Midwestern Prairie. How Much Is Gone?

Farming has ruined and damaged a lot of the rich soil of the Midwestern farms of the United States, and a team of researchers just came up with an astounding approximate of just how much is gone.

According to an NPR report, the most fertile topsoil is totally gone from one-third of the entire land allotted to growing crops throughout the upper Midwest, said the scientists. However, some researchers have remained skeptical about the methods that yielded said results.

The research, it was said, appeared from mere observation, one that those who fly over the US Midwestern farms can verify for themselves. The bare soil's color varied, and such a variation is often linked to the quality of the soil.

The soil found to be darkest in color is popularly known as topsoil. For soil scientists, this layer is called the "A-horizon."

According to the University of Massachusetts, Amherst PhD Student Evan Thaler, it is the black, organic-rich soil that is ideal for growing crops.

Full of Living Bacteria

This rich soil is full of living bacteria and decaying plant roots also known as organic carbon. When the early settlers first came to the Midwest, it was all over places, developed from hundreds of years of accumulated low land grass.

However, plowing released much of the stuck carbon, and topsoil was lost to wind and water erosion. Thaler, together with his colleagues compared that color as observed from satellites, with direct gauges of soil causality that the US Department of Agriculture has carried out, and discovered that light brown soil had a very little amount of organic carbon, which was not really A-horizon soil at all.

The layer of the said topsoil had disappeared. What's more, the research team discovered that this was constantly the case on certain portions of the landscape. Thaler said, the A-horizon was nearly always gone on hilltops.

The PhD student believes that a hundred years of plowing is responsible for such an almost disappearance. Essentially, the soil slowly dropped hillsides, a little bit every year, as farmers cultivated the soil.

One-Third of Crops Growing on Erosion-Prone Hills

The team of scientists then expanded their investigation to fields of other crops including corn and soybeans, among others, within a larger area of the upper Midwest including great parts of Minnesota, Indiana, Illinois and Iowa.

Moreover, the team calculated that roughly one-third of the crops grow on erosion-prone hills. This produced their approximate that one-third of all cropland in that area had lost its topsoil.

Thaler explained, that calculation is far more than those that the US Department of Agriculture published. He said he thinks the USDA is intensely undervaluing the amount of loss.

Some other soil experts, however, are skeptical of this methodology of Thaler. University of Illinois's Michelle Wander said that the research depends on a series of hypotheses to fill in gaps in the data and such theories probably overestimate the loss of topsoil.

Wander also points out that topsoil gets mixed into original layers of soil instead of completely disappearing.

Endangered Topsoil

Even the critics of this study agreed though, that topsoil is endangered. Minnesota's state soil health specialist Anna Cates said, to her, it's insignificant whether it is exactly a third.

Maybe, she added, it is 20 percent, or even 40. So much of the topsoil had disappeared from the hills, elaborated Cates.

She also added that farmers are already aware that these eroded hilltops, as shown on Breaking News Today's YouTube video are not that productive and many of them are in quest for solutions.

Cates said, they are essentially attempting to make up for many years of fairly inconsiderate practices. She elaborated there is no quick solution for this.

However, there are definitely ways to farm that also reconstruct topsoil. They engaged less tilling or none at all. Lastly, the expert said, farmers can grow grass and produce hay instead of corn.

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