Modern agriculture is eroding soils at a rapid pace

What can possibly rival the erosive force of a glacier, which over time carves out deep valleys or crevices that will eventually become lakes? Human activities. Modern agriculture in particular, according to a study published in early April in the journal Geology . It involves analyzing sediments from the Minnesota River in the United States, whose course was traced at the end of the Ice Age.

This study adds to a body of work on the American continent that shows how the settlement of European colonists profoundly altered the morphology of the land, and, in doing so, the quality of the soil. “In less than 200 years, we have transformed these landscapes about 10 times faster than the Ice Age,” Andrew Wickert, a geologist at the University of Minnesota Twin Cities and co-author of the study, told Science .

Asked by the American magazine, David Montgomery, a geologist at the University of Washington, who was not involved in the work, confirms: “Agricultural erosion is one of the most significant – yet hidden – effects of human activity on the environment.” Regarding the study’s findings and conclusions, he says:

“These are exceptional data that allow us to identify a geological turning point in the modern era.”

The researchers caution that this isn't just a historical reconstruction. The erosion assessed in the study continues. Its rate, driven by agriculture, still far exceeds prehistoric rates. This is despite agricultural advances such as the use of cover crops, no-till methods, and contour plowing.

Current levels of erosion contribute to soil depletion by removing the fertile layer and weakening its ability to retain moisture and store carbon. More importantly, “experts are concerned about the long-term threats this phenomenon poses to our food security,” notes Science.