What is Humus Soil?
The thin layer of earth’s upper crust that contains only 4-12 inches (10-30 centimeters) of humus-containing soil is the foundation of all life on earth.
Humus formation is a complex biological and ecological process that involves the interplay between inorganic conversions and organic creatures such as microbes, nematodes, and earthworms.
In this article, we will explore what humus soil is, its benefits, how it is formed, and why it is the foundation of all life on earth.
What is Humus Soil?
Humus soil is a type of soil that contains a high concentration of organic matter in the form of decomposed plant and animal remains.
It is a complex mixture of various compounds that include cellulose, lignin, proteins, fats, carbohydrates, and other organic molecules.
Humus is what gives soil its dark, rich color, and it is often referred to as the “soul of the soil” because it provides plants with the essential nutrients they need to grow.
Benefits of Humus Soil
Humus soil has numerous benefits for the environment and human health. It contains a wealth of essential plant nutrients such as nitrogen, phosphorus, and potassium, which are vital for healthy plant growth and development.
Humus soil also helps to retain moisture in the soil, which reduces the need for irrigation and conserves water. It improves soil structure and fertility while reducing soil erosion and nutrient leaching.
Humus soil supports the growth of microbes and beneficial soil organisms such as earthworms, which are essential for a healthy ecosystem.
How is Humus Soil Formed?
Humus formation is a biological process that occurs in two stages. The first stage involves the decomposition of organic substances and minerals in the soil.
This process is carried out by soil microorganisms, mainly lithobionts, which are the mediators between stone and life.
These microbes produce a life-giving substance from the non-living mineral, which forms the basis for living matter, earth, plants, animals, and human beings to begin, step by step, to build.
The second stage of humus formation involves the development of totally new combinations of the broken-down products.
This leads to the initial stages of humus. The process of humus formation is ongoing, and it is influenced by various factors such as soil type, climate, vegetation, and land-use practices.
It takes a long time for humus soil to form. While untouched soils in primeval forests can at best reach 20 percent humus content, cultivated soils with 2 percent humus content are considered high-quality farmland. Real humus stores only emerge over the course of millennia.
Why Humus is the Foundation of Life on Earth
Only soils with optimal structural tilth, which has a humus content of 8-10 percent, can support plant growth.
The remaining 98 percent of soil mass is of purely mineral origin, resulting from the decomposition and erosion of rock.
Humus soil provides a necessary and rare balance between the organic and mineral components of soil. It provides plants with essential nutrients while improving soil structure and fertility.
Almost all plant communities, except for leguminous plants and untouched forests, use up more humus than they can produce.
Each harvest and each growth of cultivated plants is accompanied by a loss of humus. The lost humus cannot be replaced by any kind of mineral fertilizer.
Both deciduous woods and mixed forests can provide their own humus because they can make use of their own discarded leaves.
Even in nature, without human influence, humus is only produced in deciduous forests and on undisturbed land.
Manure, with its high proportion of animal excrement, cannot support natural humus formation. Manure has to be turned into humus before it can be used for fertilization.
This is because the microbes living in the soil are more favorably disposed toward the decomposition of pure cellulose than the disintegration of animal excrement, which leaves the intestines in an anaerobic state.
If manure is introduced to the soil without being turned into humus, it remains an alien element for quite a long time, and the microbes inherent in the soil are driven out.