It is the O horizon. The A horizon is the mineral horizon and does include a large amount of organic material but the O horizon contains the most abundant amount of organic matter. The O horizon overlies the A horizon.
The correct order of soil horizons, from top to bottom, is O horizon, A horizon, E horizon, B horizon, C horizon, and R horizon. It is important to note that not all soils have all these horizons, as they can vary depending on the specific conditions of the soil.
The correct order of soil horizons from top to bottom is O, A, E, B, C. The O horizon is organic matter on the surface, the A horizon is topsoil with organic material mixed with mineral particles, the E horizon is a zone of leaching, the B horizon is subsoil with accumulated minerals, and the C horizon is weathered parent material.
The O in the O horizon stands for organic matter, which consists of partially decomposed plant material like leaves and twigs. This layer is found at the surface of the soil and is an important component for soil formation and nutrient cycling.
the "O" horizon
Soil horizons consist of different layers with unique characteristics: O horizon: Organic matter such as leaf litter and decaying plant material. A horizon: Topsoil rich in organic matter, minerals, and living organisms. B horizon: Subsoil with enriched minerals leached from above. C horizon: Weathered parent material that has not undergone much alteration.
The B horizon is the layer of soil underneath the A horizon, which is under the O horizon. The B horizon contains minerals and sand grains as well as organic material. If you didn't get it when your teacher explained it, ask him/her aboput it. They are sure to explain better than I can!
The 5 layers in a complete soil profile are the O horizon (organic matter), A horizon (topsoil), E horizon (eluviated layer), B horizon (subsoil), and C horizon (parent material). These layers collectively make up the soil profile, each with different characteristics and roles in supporting plant growth and ecosystem function.
The O-Horizon
Topsoil typically consists of the uppermost soil layers, including the O horizon (organic matter layer) and the A horizon (mineral layer). These layers are rich in nutrients and organic matter, making them essential for plant growth and agriculture.
The uppermost layer of the soil, known as the O Horizon, contains the highest amount of organic material. This layer consists of decomposing plant and animal matter, as well as living organisms like fungi and insects that aid in the decomposition process.
The five soil horizons are O horizon (organic matter), A horizon (topsoil), E horizon (eluviated or leached layer), B horizon (subsoil), and C horizon (parent material). These horizons collectively make up the soil profile and influence soil characteristics and fertility.