Soil is made up of three main components – minerals that come from rocks below or nearby, organic matter which is the remains of plants and animals that use the soil, and the living organisms that reside in the soil.
What are the main ingredients in soil?
Soil is a mixture of four main ingredients: weathered rock, organic matter, air, and water. The weathered rock can be in the form of sand, silt, clay, pebbles, or other size rocks. Organic matter can be anything from old leaves, dead animals and plants, or tiny living things.
The largest component of soil is the mineral portion, which makes up approximately 45% to 49% of the volume. Soil minerals are derived from two principal mineral types. Primary minerals, such as those found in sand and silt, are those soil materials that are similar to the parent material from which they formed.
Soils are chemically different from the rocks and minerals from which they are formed in that soils contain less of the water soluble weathering products, calcium, magnesium, sodium, and potassium, and more of the relatively insoluble elements such as iron and aluminum.
Soil consists of four components: mineral particles, water, air, and organic matter. Some examples of mineral matter are gravel, stone, clay, sand, and silt. Mineral particles are vital for the growth of plants. The water in soil is rainwater that has been absorbed by the other components in the soil.
Soil covers much of the land on Earth. It is made up of minerals (rock, sand, clay, silt), air, water, and organic material (matter from dead plants and animals).
A soil with a mixture of clay, silt, sand and humus is often referred to as a loam. It contains the nutrients necessary for plants, holds sufficient water to make them available to the plant roots, with air pockets between the particles to allow good drainage, and it holds together well.
Soil is the thin layer of material covering the earth's surface and is formed from the weathering of rocks. It is made up mainly of mineral particles, organic materials, air, water and living organisms—all of which interact slowly yet constantly.
Bedrock is the solid layer of rock beneath the soil. Soil is a mixture of rock particles, minerals, decayed organic material, air, and water. The decayed organic material in soil is humus, a dark-colored substance that forms as plant and animal remains decay.
Living organisms present in soil include archaea, bacteria, actinomycetes, fungi, algae, protozoa, and a wide variety of larger soil fauna, including springtails, mites, nematodes, earthworms, ants, insects that spend all or part of their life underground, and larger organisms such as burrowing rodents.
The Parent Material may be directly below the soil, or great distances away if wind, water or glaciers have transported the soil. The soil formation process is termed 'pedogenesis'. Climatic conditions are important factors affecting both the form and rate of physical and chemical weathering of the parent material.
Soil is a vital part of the natural environment. It is just as important as plants, animals, rocks, landforms, lochs and rivers. It influences the distribution of plant species and provides a habitat for a wide range of organisms.
Soil is defined as the unconsolidated portion of the earth's crust modified through physical, chemical, and biotic processes into a medium capable of supporting plant growth. The Soil Resources Inventory (SRI) includes: Maps of the locations and extent of soils.
There are three main horizons (called A, B, and C) which are present in all soil.
- Organic - The organic layer (also called the humus layer) is a thick layer of plant remains such as leaves and twigs.
- Topsoil - Topsoil is considered the "A" horizon.
- Subsoil - Subsoil is considered the "B" horizon.
There are three basic types of soil: sand, silt and clay. But, most soils are composed of a combination of the different types.
- 9.1 Soil processes important for nutrient uptake.
- 9.2 Carbon.
- 9.3 Nitrogen. 9.3.1 Nitrogen gains. 9.3.2 Nitrogen sequestration. 9.3.3 Nitrogen losses.
- 9.4 Phosphorus.
- 9.5 Potassium.
- 9.6 Calcium.
- 9.7 Magnesium.
- 9.8 Sulfur.
Here are the major properties of soil.
- Texture. The texture of the soil refers to the proportions of three major materials within it: sand, clay and silt.
- Structure. Linked to the texture is the structure of the soil.
Soils are complex mixtures of minerals, water, air, organic matter, and countless organisms that are the decaying remains of once-living things. It forms at the surface of land – it is the “skin of the earth.”
Soil conservation is the preventing of soil loss from erosion or reduced fertility caused by over usage, acidification, salinization or other chemical soil contamination. Slash-and-burn and other unsustainable methods of subsistence farming are practiced in some lesser developed areas.
Despite being a non-renewable resource, meaning its loss and degradation is not recoverable within a human lifespan, soil is often overlooked. It is estimated that today, 33 percent of land is moderately to highly degraded due to the erosion, salinization, compaction, acidification and chemical pollution of soils.