Soil

Soil is a important product of weathering and covers most of the land surface. Weathering produces a layer of rock and mineral fragments which is called regolith. Soil is apart of this regolith that helps support plant growth. There are three important characteristics of soil are compositon, texture and structure.Soil's composition is made up of; mineral matter or broken-down rock 45%; organic matter or humus 5%; water 25%; air 25%.  Soil varies at different depths in composition, texture, structure, and color. These variations divide the soil into zones known as soil horizons. A vertical section through all of the soil horizons is called a soil profile. In some soil profiles, the soil horizons blend gradually from one to another, soil horizons are quite distinct. Three common types of soil are pedalfer, pedocal, and laterite. Soil is a very important part of life on Earth and is needed for plants, animals, and humans.