Soil is underfoot on nearly every the surface of the planet, including the ocean floor. Soil might be taken for granted or rarely considered unless there are plans for a garden, rain has made the yard muddy, or when the kids have discovered the mud puddle. The process of soil formation plays a vital role in how the planet is fed, watered, and supported. Without soil, the earth would be a very different place.
Soil serves as more than a growing medium. It takes on many roles as it forms to shape the land. Human activity and resulting climate changes have increased soil’s vulnerability and exacerbated the natural process of erosion, yet reverence for soil’s gifts continues as humans dig their hands in to immortalize soil’s impact on life itself. Though everyone encounters soil nearly every day, most don’t know what soil is made from or how it is formed.
What is Soil Made From?
Considered the “skin of the earth,’ soil is an essential component to life on the planet. Soil can be a complex combination of organic matter found in decomposition and may include materials like sand, silt, or clay. Soils may be thin and just a few millimeters deep, or they might have several meters of depth, and it is dependent on the stability of the soil and whether it has protections in the form of supporting vegetation and moisture. Soils, depending on their region, may be home to fungi, bacteria, insects, and air – all working together in the process of soil formation.
Soil is developed from several physical and biological operations; it is the foundation of life and ecosystem health. As soil is created from rock, certain factors determine what soil is made of and which soil types form. Rock and sediment are under the influence of the following five elements that comprise soil’s structure.
1. Lithosphere: This is where rock and sediment form, some of which might be leftover from thousands of years of glacial retreat. Breakdown of these materials may occur from abrasion or changes in temperature.
2. Biosphere: This contains the influencing factors of flora and fauna. When other living organisms decide to call a rock home or pass through or over the rock on the way to somewhere else, this combination of breakdown contributes to soil’s final composition.
3. Hydrosphere: Water plays a crucial role in the development of soil’s stability and fertility. The carriage of other materials and water’s constant movement erode rock and debris.
4. Atmosphere: Climate influences the rate at which material is weathered as well as the speed of its decomposition.
5. Topography: Elevation and slope of land also influence soil development. Differences in land’s peaks and valleys play a role in vulnerability and erosion.
How is Soil Formed?
As these elements come together, they form different soil types or soil series. Understanding soil’s composition is directly related to productivity, risks, and hazards that might come into play, as well as soil’s suitability for use. Soil might be compromised and lose its fertility and stability due to erosion through wind and water. Although erosion is a normal and natural process and contributes to soil formation, excessive erosion can have the opposite effect.
Soil is typically comprised of four or more layers of deposits referred to as horizons.
1. O Horizon: This is organic accumulation above mineral soil. Fallen leaves, stray grasses, and other debris lying atop the surface are usually defined as the O layer.
2. A Horizon: This layer is mineral soil, commonly called topsoil. Topsoil is defined as the uppermost layer where plants, roots, insects, and microorganisms live.
3. B Horizon: This layer of subsoil is often indicated by color change, as its exposure to the elements and materials differs from the upper layer.
4. C horizon: Located under B Horizon, this layer is not exposed to changing weather conditions or the same forces upper horizons might experience. C horizon is considered parent material and where soil formation gets its blueprint.
While there might be only a few major soil classifications, there are thousands of soil types. Soil within the same series contains similar characteristics including texture and rock content, depth to water table, soil depth, and temperature. The slope of the land, soil’s position, and precipitation play roles in soil’s formation and type.
What is Soil’s Function?
Soil serves numerous functions and is responsible for ecosystem health and regulation alongside human health and creativity.
- Soil supports ecosystems. Species survival, plant growth, and habitat are all influenced by soil. Insects and microbes call soil home, and their activity also impacts soil development and type.
- Soil regulates ecosystems. Soil regulates the speed at which nutrients, carbon, and water cycle through the environment. Soil provides clean air and water through infiltration while the same process limits exposure to disease and ensure soil’s resilience.
- Soil provides food and nutrients for species survival. Clothing and habitats are comprised of soil elements or take their instruction from the soil. Soil provides food and nutrition to the entire planet.
Cultural Awareness and Artistry
Soil has inspired creativity and artistry throughout the ages. Soil is recognized in cultural beliefs and religions in order to give thanks for its contribution to life and living.
Soil and its corresponding landscape have inspired artists for centuries. From books and pottery to paintings and poetry, the earth’s vast and changing topography inspires dreamers and visionaries alike.
The health and wellbeing of the planet and its inhabitants are directly affected by soil’s formation, type, depth, and health. Soil is a living, changing material that is subject to the same vulnerabilities as any other living thing. Managing soil’s function and utilizing it to its best ability is vital to overall plant growth and habitat restoration.
There are real dangers to compromising topsoil as well as each horizon below. Erosion compromises soil health by robbing its nutrients and leaving it vulnerable to disease. People must remember the value of soil and the life it provides. They must look after the well-being of this seemingly small but astronomical part of the world.