PLANT PHYSIOLOGY
PLANT GROWTH
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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sand, silt, and clay
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topsoil, subsoil, and root zone
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topsoil, subsoil, and bedrock
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None of the above
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Detailed explanation-1: -Soils are named and classified based on their horizons. The soil profile has four distinct layers: 1) O horizon; 2) A horizon; 3) B horizon, or subsoil; and 4) C horizon, or soil base ([link]). The O horizon has freshly decomposing organic matter-humus-at its surface, with decomposed vegetation at its base.
Detailed explanation-2: -The layers of the soil are called horizons. The uppermost horizon is called the topsoil layer. The topsoil layer is a mixture of sand, silt, clay and broken down organic matter, called humus.
Detailed explanation-3: -The topsoil is the uppermost layer of the soil. Below the topsoil is the subsoil. The third layer comprises of weathered rock material. Finally, the bottomost layer is called the bedrock or parent rock from which the soil is formed.