ABSTRACT
Soil is a naturally occurring mixture of mineral and organic ingredients with a definite form, structure, and composition. The composition of soil changes from one location to another, although regional soils tend to be of the same type. A soil is composed primarily of minerals that are produced from parent material that is weathered or broken into small pieces. Soil consists of horizons near the Earth’s surface that, in contrast to the underlying parent material, have been altered by the interactions of climate, relief, and living organisms over time. Soils develop as a result of the following factors: parent material, climate, living organisms, landscape position, and influence of time on decomposition. Parent material is the unconsolidated organic and mineral material in which soil formation begins. Plants affect soil development by supplying upper layers with organic matter, recycling nutrients from lower to upper layers, and helping to prevent erosion.
