If you dug a hole 100 feet down into the ground, what would you discover? The first thing you’ll notice is that you’ve burrowed through many distinct layers of soil. Just what can you learn from this cross-section of earth waiting below the surface? Let’s take a closer look, explore the importance of soils, and see why dirt is crucial to all life on Earth.
Why Is Soil Important?
Soil is essential to life as we know it here on terra firma. It provides a place for plants to grow and a home for insects and fulfills other critical duties that our flourishing planet depends on, including the following:
A Medium to Grow Food
Soil is an essential component of plant growth. It supports their root systems, protects them from erosion, and keeps them growing upright. It also provides plants with essential minerals and nutrients, including water.
A Home for Many Organisms
A large variety of animals, insects, and other microbes live in soil and depend on it for food and air. It’s a diverse habitat for a wide range of organisms, such as worms and termites, that help break down organic matter and enrich the soil. It’s also a nesting ground used by many creatures to raise their next generation.
A Water Filtration System
Much of our planet’s rainfall and snowmelt flows to larger water bodies like streams and lakes, but much of it soaks into the ground. As it continues to seep through many layers of soil, it’s filtered clean of dust, chemicals, and other contaminants. This filtered water provides both plants and humans with one of the purest sources of liquid needed for good health and prime growth.
It Helps Maintain Atmospheric Gases
Dirt helps maintain adequate aeration and provides air to plant roots. By acting as a storehouse, layers of dirt help to regulate atmospheric carbon dioxide. Soil contains nearly twice as much carbon as the air, plus nitrogen and phosphorus. These nutrients are stored, transformed, and cycled into the ground.
Types of Soil
In the U.S., there are 12 classifications of soil textures. Here, we will discuss the four most common types, including the following:
Sandy soil has a gritty feel and warms up quickly in spring. It’s free draining and features large, hard particles, though it’s inferior at holding water.
Sand doesn’t bind very well with soil aggregates and it’s often low in nutrients because the nutrients wash away easily. The natural weathering of bedrock like limestone, shale, granite, and quartz produces sand.
This type of soil has a fine, smooth texture and holds water better than sand. It makes a superior choice for crop cultivation because it holds more nutrients than course-particles. It’s heavier than sandy soils but not as heavy as clay. Silt forms when dust and fine debris are carried by water or ice and deposited on the ground.
Clay is made up of the smallest particles. They bind incredibly well, resulting in little or no breathing spaces for plants and insects. Clay is sticky when wet and easily molds into any form. When dry, it hardens into a rock. Soil that is rich in clay doesn’t drain very well at all and is thought to originate in the sediment of sea or lake bottoms.
Loam is a mixture of sand, clay, and silt particles. It’s high in the essential mineral calcium and retains water well. Most agriculturalists agree that loam is ideal for most crops. It’s a vegetable farmer’s top choice as it’s full of decomposed organic material and plenty of nutrients. These nutrients demonstrate why organic matter is important in soil. It also has a soft texture and is easy to cultivate.
Factors That Affect Soil Formation
The ground produces soil based on five factors. The interaction between parent material, time, climate, landscape, and the bounty of healthy organisms is what gives birth to new dirt.
Soil’s parent material refers to the minerals and organic matter from which it’s formed. It will retain its origin rock’s color, texture, structure, and mineral composition.
It can take many years to break down parent material into dirt. As the land ages, new organic matter adds to the mix, and exposure to water and wind changes its features. As earth gets buried over time, it may evolve into a completely different type of soil.
Climate is often one of the most active factors that shape the formation of new soil. The two most critical climatic components are temperature and rainfall. A warm, damp climate means more vegetation and organic matter and the increased potential for water erosion.
The landscape also plays a prominent role in soil formation. Water runs down steep, long slopes quickly, leaving behind poor quality soil on the hillside and an abundance of fertile land at the base. Expose these hills to direct sunlight, and these extreme conditions dry out the ground, making it less productive.
Uses of Soils
Much of the planet’s exposed surface has a covering of thick soil. It’s a precious ecosystem that offers mankind many useful applications.
According to the North Carolina Department of Agriculture, plants derive 13 essential nutrients from soil alone. It’s an excellent medium for growing food, as the roots use the dirt for strength and stability, too. Agriculture is definitely one of the most important functions of soil.
From adobe covered structures to building blocks made of pure mud, soil has played an integral part in humanity’s building process for thousands of years. When compacted and dried, earthen bricks can support enormous loads. Providing shelter reveals yet more of the importance of soil.
Clay is an essential component for making pottery. Even our ancestors knew that you just need to add water to this type of soil to create beautiful, functional ceramics. Clay is quite versatile, and once dry holds its shape indefinitely.
Health and Beauty Products
Soil’s microbes can be harmful to some strains of bacteria, which is why it’s commonly used to make antibiotics, ointments, and anti-cancer drugs. Even cosmetologists make beauty products from clay, including blush, foundation, facial masks, and toothpaste.
Soil is essential to all life on Earth. Its abundant supply takes years to replenish, and with so many varied uses, it’s conservation is important.