mull
Quick Summary
The term "mull" has several meanings, but in geology, it refers to a specific type of soil layer. Mull is a friable forest humus that forms a mixture of organic matter and mineral soil, gradually merging into the soil beneath it. This term was first used in 1923 to describe this geological formation.1
It is important to distinguish this geological term from other uses of "mull," such as the Scottish island of Mull, the mineral mullite found in ceramics, or the verb "to mull," which means to grind, mix, or ponder.234
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deciduous forest…granular humus layer known as mull, which is a porous mixture of organic material and mineral soil. Mull humus harbours many bacteria and invertebrate animals such as earthworms.
Read More…granular humus layer known as mull, which is a porous mixture of organic material and mineral soil. Mull humus harbours many bacteria and invertebrate animals such as earthworms.
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temperate forestEnvironment…temperate deciduous forest soils are mull soils, which have a high level of organic matter especially close to the surface that is well mixed with mineral matter. Variations in soil materials and fertility have a strong influence on the types of trees that will dominate the forest. For example, in…
Read More…temperate deciduous forest soils are mull soils, which have a high level of organic matter especially close to the surface that is well mixed with mineral matter. Variations in soil materials and fertility have a strong influence on the types of trees that will dominate the forest. For example, in…
Read More