Facts About Soil

Interesting Facts About Soil

• Soil is an important part of ecosystem. Life in an ecosystem is directly related to the type and composition of the soil found in it.
• Soil is formed due to chemical and physical withering of rocks. Withering forms the sand particles and debris of plants and animals makes it fertile. Soil forms earth’s outermost layer.
• Rain, thunder, flood, erosion, etc. play major role in soil formation. Seasonal expansion (during summer) and contraction (during winter) also causes the rock to wither, forming tiny sand particles.
• Geology of a particular area contributes to the properties of soil in that region. Take the valley province of Pennsylvania as an example. This region has sedimentary beds formed with different layers of sandstone, limestone and shale. Sandstone is hard and it forms coarse soil. Limestone withers off very fast and the calcium carbonate present in it dissolves in water and gets distributed, adding to the fertility of the soil. Shale soil has a fine texture and is acidic in nature. It has scarce nutrients.
• The top layer of soil is called humus. Humus is composed of fungus, bacteria and other microorganisms.
• Formation of soil is a lengthy process; it takes about 500 years to form a layer of soil of about 1 inch thickness.
• If you spread five tons of soil over one acre of land, it would be as thin as a dime!
• Soil, which has many organic contents in it, is rich in minerals and nutrients. Rocks are the major source of these minerals.
• 45% of an average soil sample is comprised of minerals. Of the remaining 55%, 25% is composed of water, 25% air and the remaining 5% of organic matter.
• Soil is abundant in microorganisms. These microorganisms help in decaying dead matter in the soil and add to its organic content.
• 1 gram of soil contains about 5000 to 7000 species of bacteria. One acre of soil can hold 5-10 tons of living beings!
• There are infinite types of soil on earth. Scientists have discovered about 7000 types of soil in United States and about 10000 types of soil in Europe.
• These different types of soil are classified according to their texture, color and components.
• Some types of soil have vibrant colors like red, yellow, white etc. However, most types are black, brown or grey in color.
• Soil could be of different textures like coarse, fine etc. Sand has the largest particles while clay has the finest. The texture of the soil can be found out by rubbing it between the fingers. Sandy soil has a gritty texture while silt has a silky one.
• Soil could be smooth, crumbly, rough, sticky, silky or creamy depending upon the minerals, slit, clay or sand content in it.
• Soil has many layers and these layers are called horizons. The various horizons of soil are horizon O, horizon A, horizon B and horizon C. The topmost layer is horizon O and is highly fertile.
• Horizon A lies below horizon O and this layer is also characterized by the presence of microorganisms and other critters. It has organic debris and wastes shed from the roots of trees.
• Horizon B lies below horizon A. This layer is tough and hard that it cannot be penetrated by roots or critters.
• Horizon C lies below horizon B. This layer consists of the parent materials of soil formation. Bedrock is the major component of this layer, however, other secondary materials brought along by factors like ice, rain, erosion, etc. are also found here.
• Plant and soil maintain a mutually benefitting relationship. Soil provides an anchor for the plant to live and supplies water and essential nutrients and the roots of the plants penetrate the soil and allow air to pass, thereby helping many organisms to thrive in soil. Also, the roots prevent soil erosion and hold the soil together.
• Each type of soil has a specific PH which has a direct influence on the type of plants and microorganisms that can survive on it. However, you can adjust the PH of a soil by adding external substances. For instance, you can add lime to acidic soil to reduce its acidity to the desired level. On the other hand, you can acidify the soil with nitrogen containing fertilizers if it is highly alkaline.