The Secret World Beneath Our Feet: Digging Into the Hidden Wonders of Soil

Wendell Berry, American writer, environmental activist, and farmer once said ‘The soil is the great connector of lives, the source and destination of all.’

When I was a child, I would spend hours simply playing in the soil. Digging, squeezing, sometimes even tasting it, I would sit out in the rain and discover amazing creatures with weird and wonderfully shaped bodies, numerous legs, and sometimes dangerous-looking claws.

As adults, we walk on it every day, we grow food in it, we work hard to own land. And as Wendell Berry reminded us some of us will even be buried in it.

Soil, it is all around us, but what do we really know about it?

The everyday, run-of-the-mill person will hold their hands up and say, “nothing”! Scientists might argue we know more about it now than ever before. This is true, but for many years, we knew very little.

Which is weird when you sit back and really think about it – it is so close to us. Soil is one of the most diverse habitats on Earth. It is home to a myriad of organisms, including bacteria, fungi, insects, and other microorganisms. At the risk of sounding geeky, this biodiversity is crucial for ecosystem functions like recycling nutrients and the decomposition of matter.

So how is soil made? Soil formation is a slow process, taking hundreds to thousands of years. It involves the weathering of rocks and the accumulation of organic material. However, human activities such as deforestation, agriculture, and urbanization have negatively impacted soil, contributing to degradation. This includes erosion, compaction, and the loss of organic matter, all of which threaten soil health and productivity.

So why is soil so important? Soil is fundamental for food production, water filtration, and storing carbon. It supports plant growth, which in turn supports animal life and human societies. Big stuff!

Here are some funky facts!

The more you look into the murky, unknown world beneath our feet, the more it becomes interesting.

For example, a teaspoon of healthy soil contains between 100 million to 1 billion bacteria. One gram of soil can contain 10,000 different species of bacteria!

Mycorrhizal fungi are tiny, helpful fungi that live in the soil and connect to plant roots. They help plants by sharing water and nutrients through an underground web. It's like having a secret underground web that lets plants "talk" to each other and share things.

Arbuscular mycorrhizal fungi forms a symbiotic relationship with grapevine roots.

And remember, all this is going on under our feet!

There is more: through this underground web, the fungi can move important nutrients, like food and water, from one plant to another. If one plant has too much and another plant needs some, the fungi help them share.

Young or weak plants that can't get enough nutrients on their own can get help from stronger plants through the fungi's web. This makes sure all the plants in the group stay healthy.

If a plant gets attacked by bugs, it can send a warning through the fungi's web to other plants. This way, the other plants can get ready to defend themselves before the bugs reach them.

There is a lot more going on under our feet than we appreciate!

The top 15 cm of soil in an acre can contain between 1 and 9 tonnes of living organisms, including roots, microorganisms, and invertebrates.

In a square meter of healthy soil, there can be up to 1 million earthworms, insects, and other invertebrates. Earthworms alone can number between 100 to 500 individuals per square meter in fertile soils; they are the engineers of the soil.

Worms doing their thing

Their burrowing and digestion of organic matter create channels that aerate the soil and increase its ability to absorb water. Earthworms create extensive tunnel systems in the soil, which can extend up to 5 meters (16 feet) deep.

So next time we stroll across that patch of land, stop, take a moment, and think about what is going on beneath our feet. Channel that inner child, get on your knees, and explore. You don’t have to travel to the furthest reaches of space or the deepest oceans to find another world – it is right there beneath our feet.