Earth is Losing Farmland at an Alarming Rate

2015 has marked the International Year of Soils, an event that many members of the public missed — but they shouldn’t have, because soil is vitally important for human survival. Ominously, a study from the Grantham Centre for Sustainable Futures indicates that in the last 40 years, humans have chewed through 33 percent of the Earth’s topsoil, thanks to development and harmful farming practices. The grim findings are a bad sign for the future, as we rely on soil not just for sustenance, but also as a carbon trap, key component of nearly every ecosystem on Earth, and breeding ground for organisms with tremendous commercial and humanitarian applications, such as bacteria that could contribute to the development of cutting edge pharmaceuticals. We should be worshiping the ground we walk on, and this study indicates that we’ve been doing just the opposite.

Soil depletion is often far off on the minds of members of the public because they’re not intimately connected with farms and other settings where soil plays a vital role. When they think about soil damage, they might imagine the Dust Bowl of the 1930s, caused by unsustainable farming practices and then-unusual farming conditions, and they may not be aware of the extent of desertification, soil salination, and other problems rendering once vibrant farmland unusable. In the United States alone, 50 acres of farm and ranchland alone fall to the developer’s backhoe every hour, and that soil loss doesn’t account for damage caused by poor farming practices, a problem across the United States as commercial farms attempt to eke as much as possible out of the land.

Heavy ploughing disrupts the soil, making it impossible for microorganisms to survive. When that soil is further treated with fertilizers, fungicides, pesticides and specially treated herbicides, it adds to the problem. Other land is overgrazed, or subjected to aggressive harvesting practices that strip trees and shrubs which normally act to hold the soil in place with their tough networks of roots. The damaged, dry, crumbling soil can’t sustain life unless it’s shocked with even more fertilizers, compounding the problem, and it washes away in rains and floods, rushing out into the ocean and carrying a burden of agricultural chemicals with it — like the fertilizers causing algae blooms that disrupt marine environments, illustrating the chain effect caused by disruption of soil ecosystems.

It can take hundreds of years for up to an inch of topsoil to develop, assuming that the soil is left alone and the conditions are right — that the weather isn’t too hot or dry, too wet or humid. Trees, living organisms and minerals need to break down slowly, building up a rich layer of dark, crumbly soil that’s full of nutrients for plants to grow in, and while the soil breaks down, it also needs to be held in place with living flora. This painstaking process isn’t happening quickly enough to replace soil lost to human activities, which are breaking down arable land at a rate approximately 100 times that of soil replacement.

Soil loss means a lot of things for the future of humanity. As a source of crops, breakdown of usable soil will equate to a decline in available food, potentially adding to the problem of world hunger, especially in developing nations that are already aggressively exploiting their arable land to grow enough to feed their populations. Luxury crops like coffee and chocolate, already threatened by climate change, are likely to experience extreme scarcity. Low-lying areas will flood, as healthy soil normally creates a buffer zone that limits storm surge and keeps rivers back. Atmospheric carbon could rise, as soil is a major carbon sink. Massive soil plumes from major rivers like the Amazon could continue to grow, adding to the problems experienced by the world’s oceans.

Researchers warn that the Earth’s soil is near a tipping point. In the short term, humans need to radically reform farming practices, allowing fields to lie fallow with cover crops to restore nutrients and prevent soil loss. They also need to reduce the use of heavy farming equipment, particularly ploughs, and to use crop rotation to avoid stripping nutrients from their farmlands. High-efficiency methods of farming that don’t devastate the Earth are available, and farmers need to be educated about them so they can integrate them into their routines. In areas where people are not farming, forest conservation and restoration are critical, as forest ecosystems both trap and rebuild soil.

It took billions of years for the Earth to develop into the rich, ecologically diverse place that it is, and much of that diversity hangs by a thread. Soil is a key piece of the puzzle that sustains life on Earth, and if we lose it forever, it will take billions more years for the Earth to recover.

Photo credit: Idaho National Laboratory

62 comments

Mark Donner
Mark Donner1 years ago

The infinite stupidity of humanity is mind boggling: here's a logical concept, "unlimited growth in a finite world with limited resources" Add that to the glorification of genocide and ecocide and of the extermination of life wherever it is to be found, and you have the definition of humanity.

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Mark Donner
Mark Donner1 years ago

Earth doesn't have "billions of years" to recover. In two billion years the sun will have gotten hot enough that Earth will be uninhabitable. Good job, death humans.

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Siyus Copetallus
Siyus Copetallus1 years ago

Thank you for sharing.

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Sarah Hill
Sarah Hill1 years ago

Farmers are no longer utilizing crop rotation.

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Nikki Davey
Nikki Davey1 years ago

Not good.

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Kamia T.
Kamia T1 years ago

The sad part is that there is so much you can do to add to the topsoil on the land under your stewardship, if you only want to. When I first came to my property, it was nearly solid rock. Now there is almost a foot of good soil on top through mulching, composting and not cutting everything down to the ground.

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mari s.
Mari S1 years ago

First, we can build upward -- second, in warmer climates, we can build environmentally friendly easy to assemble structures. == In summary, we must be mindful & considerate -- we share this planet with other life, who, by the way, also belong to our earth's family.

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mari s.
Mari S1 years ago

First, we can build upward -- second, in warmer climates, we can build environmentally friendly easy to assemble structures. In summary, we must be mindful and considerate--

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Carole R.
Carole R1 years ago

This is extremely troubling. Too many houses, not enough open land.

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Paul Carter
Paul Carter1 years ago

The problem is human beings and their "needs" to gather to them useless things and to prolifically procreate. If most couples had only 2 children and people who never produced any were rewarded; if alternative lifestyles that did not produce offspring were encouraged, if abortion and contraception were encouraged especially where there is already extreme poverty and a shortage of food; then maybe we could look forward to a future. As it is we will make ourselves and probably 90% of the other species extinct. Perhaps in a million years another sentient species will evolve to take our place after the planet has recovered from the most devastatingly greedy and stupid species to evolve on this planet so far.

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