The upper layer is the part of the C soil horizon where organic matter is broken down. The C horizon may be described as soil among the rocks, as opposed to rocks among the soil characteristics of the overlying A and B horizons. It receives the name regolith because of the preponderance of non-organic matter.
the A horizon
the A horizon
The O horizon, also known as the organic horizon, contains the most organic matter in soils. This layer consists of decomposed plant materials like leaves, branches, and other organic debris that have not yet fully broken down.
A horizon
O-Horizon: leaf litter, organic material A-Horizon: plough zone, rich in organic matter B-Horizon: zone of clay, iron and organic matter C-Horizon: weathering zone, little organic matter and little life R-Horizon:unweathered parent materia
Soil is a mixture of broken down rock and broken down organic plant matter.
Organic matter that is broken down into soil is called humus. Humus is a dark, organic material that forms in soil from the decomposition of plant and animal matter. It helps improve soil structure, nutrient content, and water holding capacity.
The B horizon typically contains clay, organic matter, minerals, and nutrients that have leached down from the topsoil and accumulated. It is often richer in nutrients than the underlying C horizon.
O-horizon (surface litter)=mainly partially decaying organic matter A-horizon (Topsoil)= mainly contains organic matter, living organisms, inorganic minerals. E-horizon (Eluviated zone)= low quantities of minerals,clay and organic matter due to leeching. B-horizon (Subsoil)= accumulation of iron, aluminium and clay leached down from the A and E horizons. C-horizon (Regolith)= partially broken down inorganic minerals Bedrock
animals called decomposers do exactly what their name implies, they decompose organic material. these include worms, pill bugs, and an assortment of things to tiny to see with the naked eye. I believe this is the answer to your question.
The B horizon of the soil profile accumulates leached minerals that have moved down from the topsoil (A horizon) due to the process of leaching. The B horizon generally contains minerals and organic matter washed down from upper layers, making it a zone of accumulation.
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.