FORESTRY
SOIL SCIENCE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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-has bits of decayed plants and animals-adds nutrients
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-underneath plants and grass-above topsoil
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-dark-has the most humus and minerals
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-under humus-above subsoil
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Detailed explanation-1: -Topsoil is predominantly made up of humus and minerals. Humus is the organic matter formed due to the decomposition of dead plants and animals.
Detailed explanation-2: -Thus, clay has the highest humus content. Humus is the organic component of soil, formed by the decomposition of leaves and other plant material by soil microorganisms.
Detailed explanation-3: -The topsoil layer is a mixture of sand, silt, clay and broken down organic matter, called humus. Humus is rich, highly decomposed organic matter mostly made from dead plants, crunched-up leaves, dead insects and twigs. Topsoil is the home of living things and the materials that they make or they change.
Detailed explanation-4: -The thick brown or black substance that remains after most of the organic litter has decomposed is called humus. Earthworms often help mix humus with minerals in the soil. Humus contains many useful nutrients for healthy soil.