Healthy, well-maintained soil is a key component not only to growing fruitful crops, but also to protecting the environment and sustaining agriculture for future generations.
The term “soil health” is a broad one, though.
“It’s like saying human health,” said Dr. Charles Shapiro, professor emeritus of agronomy and horticulture at the University of Nebraska-Lincoln. Much like the human body, “healthy soil” relies on hundreds of factors.
Dr. Martha Mamo, the head of UNL’s Department of Agronomy and Horticulture agrees.
“I don’t think there is bad soil or good soil,” she said, “but there are soils that are better suited for some things.”
Breaking down the composition of soil is a precise science, but there’s no one-size-fits-all formula for preparing it to raise the best crops.
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Soil erosion occurs when topsoil is worn away. Soil erosion has been a key priority for conservationists since the 1930s, when heavy winds and loose topsoil throughout the Midwest contributed to a period of drought we now know as the Dust Bowl.
“The most fertile part of the soil is the topsoil. When you lose the topsoil, you’re losing a lot of nutrients,” Dr. Mamo said. “So that’s one consequence. You will have reduced ability to produce food.”
Flowing water and hard rains can also wear soil away. When displaced soil lands in streams and road ditches, the structure of minerals meant to nourish plant roots and hold water is eliminated. Carbon and other gases are released into the atmosphere, and minerals wind up where they are harmful rather than helpful. That’s why farmers take measures to add organic matter to the ground to improve soil structure.