An anthrosol (or anthropogenic soil) in the
World Reference Base for Soil Resources
The World Reference Base for Soil Resources (WRB) is an international soil classification system for naming soils and creating legends for soil maps. The currently valid version is the fourth edition 2022. It is edited by a working group of the I ...
(WRB) is a type of
soil
Soil, also commonly referred to as earth, is a mixture of organic matter, minerals, gases, water, and organisms that together support the life of plants and soil organisms. Some scientific definitions distinguish dirt from ''soil'' by re ...
that has been formed or heavily modified due to long-term human activity, such as from
irrigation
Irrigation (also referred to as watering of plants) is the practice of applying controlled amounts of water to land to help grow crops, landscape plants, and lawns. Irrigation has been a key aspect of agriculture for over 5,000 years and has bee ...
, addition of organic waste or wet-field cultivation used to create
paddy fields.
[Major Soils of the World. ISRIC, Wageningen, The Netherlands. 2001](_blank)

Such soils can be formed from any parent soil, and are commonly found in areas where agriculture has been practiced for centuries. Anthrosols can be found worldwide, though they tend to have different
soil horizon
A soil horizon is a layer parallel to the soil surface whose physical, chemical and biological characteristics differ from the layers above and beneath. Horizons are defined in many cases by obvious physical features, mainly colour and texture. ...
s in different regions. For example, in northwestern Europe anthrosols commonly have
plaggic or terric (strongly affected by
manure
Manure is organic matter that is used as organic fertilizer in agriculture. Most manure consists of animal feces; other sources include compost and green manure. Manures contribute to the fertility of soil by adding organic matter and nut ...
) horizons, and together they cover some 500,000 hectares.
Due to the broad range of anthrosol compositions and structures compared to other soils of the same order of classification, there is debate on whether anthrosol should be included as an independent soil group.
Composition
Anthrosols can have different characteristics based on their origins. A high
phosphate
Phosphates are the naturally occurring form of the element phosphorus.
In chemistry, a phosphate is an anion, salt, functional group or ester derived from a phosphoric acid. It most commonly means orthophosphate, a derivative of orthop ...
concentration is a common indicator of decaying organic matter, such as bones, tissue, or excrement. A dark color can also be the result of a high amount of organic matter, or of calcium carbonate, iron, and manganese. A high
pH or
carbonate
A carbonate is a salt of carbonic acid, (), characterized by the presence of the carbonate ion, a polyatomic ion with the formula . The word "carbonate" may also refer to a carbonate ester, an organic compound containing the carbonate group ...
concentration, in anthropogenic terms, is likely the result of the addition of
wood ash
Wood ash is the powder (substance), powdery residue remaining after the combustion of wood, such as burning wood in a fireplace, bonfire, or an industrial power plant. It is largely composed of calcium compounds, along with other non-combustible ...
to the soil. Presence of human artifacts such as tools and waste can also be present in anthrosols. Other indicators include nitrogen, calcium, potassium, magnesium, iron, copper, and zinc concentrations.
In archaeology
The presence of anthrosols can be used to detect long-term human habitation, and has been used by archaeologists to identify sites of interest. Anthrosols that can indicate such activity can be described as, for instance, plaggic (from the long-term use of manure to enrich soil), irragric (from the use of flood or
surface irrigation
Surface irrigation is where water is applied and distributed over the soil surface by gravity. It is by far the most common form of irrigation throughout the world and has been practiced in many areas virtually unchanged for thousands of years.
...
), hortic (from deep cultivation, manure use and presence of other anthropogenic organic matter such as kitchen waste), anthraquic (from ''anthropos'' – man and ''aqua'' – water – meaning produced by man-made soil moisture management including irrigation or
terracing). Anthrosols can be detected by visual inspection of soils, or even from satellite imagery.
Other uses
Because of a high concentration of minerals, and in particular decayed organic matter, anthrosols are useful for agriculture. In an environmental context, well-managed anthrosols act as a
carbon sink
A carbon sink is a natural or artificial carbon sequestration process that "removes a greenhouse gas, an aerosol or a precursor of a greenhouse gas from the atmosphere". These sinks form an important part of the natural carbon cycle. An overar ...
.
See also
*
Anthrepts In the USDA soil taxonomy, Anthrepts is a term for soil with evidence of human habitation and farming.
See also
*Anthrosols in the World Soil Classification.
*Inceptisols of which anthrepts are a suborder of.
References
{{reflist
Types of so ...
from a different soil classification system
*
Necrosol
*
Technosols
*
Terra preta
''Terra preta'' (, literally "black soil" in Portuguese language, Portuguese), also known as Amazonian dark earth or Indian black earth, is a type of very dark, fertile human impact on the environment, anthropogenic soil (anthrosol) found in the ...
*
Pre-Colombian agriculture in the Amazon Basin
References
Further reading
* Howard, J. (2017
Anthropogenic Soils Springer International Publishing,
* W. Zech, P. Schad, G. Hintermaier-Erhard: Soils of the World. Springer, Berlin 2022, Chapter 12.3.2.
External links
profile photos (with classification)WRB homepage
profile photos (with classification) IUSS World of Soils
{{Soil type
Pedology
Types of soil
Human impact on the environment