Meaning in geology & earth sciences, with examples
/ˈhjuːməs/nounCommon term
In geology & earth sciences, humus means: The dark, stable organic material in soil that forms when plant and animal remains decay. It holds water and nutrients and makes soil fertile.
In Turkish: humus
How it is used
Used in soil science, agriculture and gardening. Humus gives topsoil its dark colour. Soils are described as humus-rich or humus-poor, and the process that forms humus is called humification.
Example sentences
Forest soils often have a thick layer of humus.
Adding compost increases the humus content of the soil.
Common collocations
humus layer
humus-rich soil
humus content
organic matter
Related terms
topsoilThe upper layer of soil, usually the top 5 to 30 cm, which is rich in organic matter and holds most plant roots and soil organisms.
soilThe loose top layer of the land surface, made of weathered rock particles, organic matter, water and air, in which plants grow.
soil horizonOne of the distinct layers in a soil profile, roughly parallel to the surface, that differs from the others in colour, texture or composition.
soil textureThe proportions of sand, silt and clay particles in a soil, which control how well it holds water, how it drains and how easily it can be worked.
