Because it has Humus which is a organic material that is from living things.
Humus.
Dark soil, also known as humus, is good for plants because it is rich in organic matter and nutrients that help support plant growth. It improves soil structure, water retention, and provides essential nutrients for plants to thrive. Dark soil also promotes the growth of beneficial soil microorganisms that help break down organic matter and release nutrients for plants to absorb.
Dark soil is good because if soil is dark it means that it is moisturized, therefore it can feed water to the roots of the plant that is growing. Soil that is not dark is bad because it is dry and does not have the moisture for the roots of the plant.
The main characteristics of dark brown soil include high fertility, good drainage, and being rich in organic matter. This type of soil is often ideal for growing a wide variety of crops due to its nutrient content and ability to retain moisture while still allowing excess water to flow through.
The topsoil horizon is dark because it contains a high amount of organic matter in the form of decomposed plant and animal material. This organic matter enriches the soil with nutrients, promoting healthy plant growth. The dark color is a result of the organic matter breaking down and mixing with mineral particles in the soil.
The dark organic rich material formed as a top layer in soil from the decayed remains of plants and animals is called humus. It is a crucial component of healthy soil, enhancing its fertility, structure, and water-retention capacity. Humus results from the decomposition of organic matter, contributing essential nutrients to support plant growth and promoting microbial activity in the soil ecosystem.
it has no soil
top soil
you are likely to find dark, humus-rich soil in an A-horizon profile because that's where dark soil is found & the composition is the particles of weathered rock materials mixed with humus.
dark soil
dark soil
Yes, it grows on top of the soil.