Soils are a composition of mineral particles 45% , organic matter 5% , air 25% , and water 25% . Brown earths are fertile and very suitable for agriculture. Their suitability for agriculture are due to their characteristics of good texture, dark colour, and ph value .
How does the soil work?
Organic matter comes from decaying plants, animals or microorganisms. Organic matter is rich in nutrients and helps stabilise the soil. You should not ignore the effects of even large living matter, roots and such help increase drainage and even provide nutrients where they are worn away from pushing through the earth.
What makes up a healthy soil?
The biological aspect is organic matter—the portion of soil that was once living plants or animals. That's one of the things that makes soil microorganisms so important. They mineralize organic matter into nutrients that crop plants can use. Soils with higher levels of organic matter are able to retain more nutrients.