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You will never believe these bizarre truths about soil


Soil is the uppermost layer of earth’s crust that is made of broken rocks. When rock particles are subjected to various physical and chemical changes, it results in minute soil particles. Apart from the plants we get to see, multiple other living beings are found surviving under or over the soil surface. Worms, insects, bacteria, fungi and countless other single celled beings co-live with the plant roots or thrive independent of it.

Soil is segregated to five layers which vary in depth and composition from each other. The soil layers are termed horizons. And the tree major horizons are the top soil, sub soil and the parent rock. The horizons in detail make the soil profile.

Other than the minerals, soil contains water and humus or decaying matter that a plant requires to grow. The composition of soil is summed up to 45% minerals, 25% water, 25% air and 5% organic matter also known as humus. However this composition tends to vary across the soil type and based on the geography too.

As agriculture improves, studying the soil has also improved vastly. The key indicator of fertile soil is the presence of earthworms in it. As they burrow through, these worms tend to loosen up the soil which makes it easy for the plant roots to penetrate inside the earth much effectively. Commonly termed as the peasant’s friend, earth worms consume about 2 tons of per acre per year, mixing it with soil after digestion. It helps in improving the soil nutrition. No wonder why they are sold at the fertilizer shops!

One other important agronomic characteristic of soil is their retention capacity. Sandy or silt soil is very loosely packed and hence is poor in retaining water. On the other hand, clay soil is comparatively tightly packed. It thus holds the water for longer hours and also retains back the minerals, pesticides or insecticides added. 

The microbial population in soil is a major advantage for the crops and plants. Few microbes share a symbiotic relationship with the roots of plants. They stay alongside the roots and fix the atmospheric nitrogen for them to grow. When you weigh the microbes in an acre of soil, it will be more than the weight of two cows! However minute they may be, microbes like bacteria and fungi plays a crucial role in maintaining the soil profile. Healthy soil can actually mark the future of the entire human population because according to soil ecologists, it can be a key to feeding 9 billion people by the year 2050.