Our soil is dying. We tend to focus on issues such as fossil fuels or water in our fight for climate action and often the issue of soil quality gets left in the dust. But it takes an average of 500 years to naturally build an inch of topsoil, and we’re losing it at 17 times that rate. Although soil degradation can be caused by a number of natural factors, increasingly soil quality is affected by human actions.
Our Changing Climate series
Today I’m going to narrow in on one of the bigger human-caused factors – industrial agriculture – in order to answer what soil degradation is, why it’s happening, and why we need to strive for better soil health.
First, what is soil degradation?
Quite simply, it means decline in soil health as a result of misuse or poor management. Soil can vary widely in its depth depending on whether it’s young or stable and old, but it’s generally teeming with life.
According to the Earth Institute at Columbia University, it’s estimated that an acre of soil may contain 900 pounds of earthworms, 2,400 pounds of fungi, 1,500 pounds of bacteria, 133 pounds of protozoa, 890 pounds of arthropods and algae, and even sometimes small mammals.
When soil health is affected, this biodiverse system wanes. 🐁
Why then is soil degradation such a big issue now?
Well, the quality of topsoil can definitely be damaged by natural occurrences like floods or wind. The rate of topsoil loss has increased radically over the last 200 years in the United States, as a result of modern agricultural practices.
In Pimentel et al’s study on the economics of soil erosion and conservation, they estimate that in the United States soil has been lost at about 17 times the rate at which it’s formed. 🐌
We can pin some of the soil loss to the intensive cultivation practices and mono-cropping of industrial agriculture. When we till and turn over a field for the next season’s crop using large combines, the topsoil is decimated much in the same way habitat is lost when clear-cutting a forest.
Tillage aerates the soil by breaking up its composition, but in the process it compacts the soil underneath and kills the wealth of micro-organisms hidden to the naked eye. As a result of many years of industrial cultivation practices, the topsoil lies void of life and then needs to be injected with nutrient-filled fertilizer and chemicals, which in turn alter the chemical makeup of the soil and make it even harder for essential organisms to survive.
In short, cultivating the soil always results in the decline of its fertility and health, and the continual use of intensive cultivation over the last century has left the United States with a looming soil crisis.
So why does degraded topsoil even matter and will it even affect me?
Yes, it will, and even more than you think. Healthy soil is the foundation for healthy plants, which are obviously crucial for our survival. This means that when we continually abuse soil structure and quality to pump out massive amounts of corn and soybeans we are making it harder to grow nutrient-dense food in the future.
👉 Right now, almost 33% of the world’s soil has been moderately or highly degraded, according to the Food and Agriculture Organization of the United Nations. And when you consider that soil can store almost three times more carbon than forests and other vegetation, killing it could lead to our inability to mitigate climate change. In order to halt this process we need to reconsider the way we approach agriculture.
In Pimentel’s study, they argue that the total investment for US erosion control would be about $8.4 billion per year. Considering that erosion causes $44 billion in damages each year, and could very well cause more, this is a no-brainer.
But on a more basic level, we should look towards the examples of innovators like Curtis Stone, who was able to create a comfortable lifestyle on a low-till, intensive urban farm. His farm builds soil health by adding compost and natural fertilizer like turkey manure to the soil, as well as keeping the cultivation of the land to a minimum.
Yes, industrial agricultural practices have provided a large amount of food to North America, but when we consider the long-term negative effects of those practices and the fact that our food system now relies heavily on just a few crops, the positives of supposed abundance merely seem like a flimsy patch for a leaky ship.
Soil is our hidden lifeline, and if we destroy it we lose our ability to feed ourselves and protect our environment.