Anthropogenic biomes, also known as anthromes, human biomes or intensive land-use biome, describe the terrestrial
biosphere
The biosphere (from Greek βίος ''bíos'' "life" and σφαῖρα ''sphaira'' "sphere"), also known as the ecosphere (from Greek οἶκος ''oîkos'' "environment" and σφαῖρα), is the worldwide sum of all ecosystems. It can also be ...
(
biome
A biome () is a biogeographical unit consisting of a biological community that has formed in response to the physical environment in which they are found and a shared regional climate. Biomes may span more than one continent. Biome is a broader ...
s) in its contemporary, human-altered form using global ecosystem units defined by global patterns of sustained direct human interaction with ecosystems.
Origin and evolution of the concept
Anthromes were first named and mapped by
Erle Ellis
Erle Christopher Ellis (born 11 March 1963 in Washington, DC) is an United States of America, American environmental scientist. Ellis's work investigates the causes and consequences of long-term ecological changes caused by humans at local to globa ...
and
Navin Ramankutty Navin Ramankutty (1970) is an agricultural geographer. As of 2015 he is a professor of Global Food Security and Sustainability at the University of British Columbia Ramankutty studies changes in land use and agricultural practices, and the effect ...
in their 2008 paper, "Putting People in the Map: Anthropogenic Biomes of the World".
Anthrome maps now appear in numerous textbooks. and in the National Geographic World Atlas. The most recent version o
anthrome mapswere published in 2021.
In a recent global ecosystem classification, the anthropogenic biomes has been incorporated into several distinct functional biomes in the terrestrial and freshwater realms, and additional units have been described for the freshwater, marine, subterranean and transitional realms to create a more comprehensive description of all ecosystems created and maintained by human activities. The intensive land-use biome comprises five distinct terrestrial ecosystem functional groups:
pastures
Pasture (from the Latin ''pastus'', past participle of ''pascere'', "to feed") is land used for grazing. Pasture lands in the narrow sense are enclosed tracts of farmland, grazed by domesticated livestock, such as horses, cattle, sheep, or swine ...
,
crops
A crop is a plant that can be grown and harvested extensively for profit or subsistence. When the plants of the same kind are cultivated at one place on a large scale, it is called a crop. Most crops are cultivated in agriculture or hydroponics ...
,
plantations
A plantation is an agricultural estate, generally centered on a plantation house, meant for farming that specializes in cash crops, usually mainly planted with a single crop, with perhaps ancillary areas for vegetables for eating and so on. The ...
,
urban
Urban means "related to a city". In that sense, the term may refer to:
* Urban area, geographical area distinct from rural areas
* Urban culture, the culture of towns and cities
Urban may also refer to:
General
* Urban (name), a list of people ...
and semi-natural ecosystem functional group. The artificial wetlands biome in the freshwater realm includes large
reservoirs
A reservoir (; from French ''réservoir'' ) is an enlarged lake behind a dam. Such a dam may be either artificial, built to store fresh water or it may be a natural formation.
Reservoirs can be created in a number of ways, including control ...
and other
constructed wetlands
A constructed wetland is an artificial wetland to treat sewage, greywater, stormwater runoff or industrial wastewater. It may also be designed for land reclamation after mining, or as a mitigation step for natural areas lost to land developmen ...
,
rice paddies
A paddy field is a flooded field of arable land used for growing semiaquatic crops, most notably rice and taro. It originates from the Neolithic rice-farming cultures of the Yangtze River basin in southern China, associated with pre-Aust ...
, aquafarms and networks of
canals
Canals or artificial waterways are waterways or river engineering, engineered channel (geography), channels built for drainage management (e.g. flood control and irrigation) or for conveyancing water transport watercraft, vehicles (e.g. ...
and ditches. The anthropogenic marine biome in the marine realm includes submerged artificial structures and marine aquafarms. The anthropogenic subterranean voids biome includes industrial excavations or artificial cave-like systems. There are two additional biomes in transitions between realms: the anthropogenic shoreline biome includes artificial shorelines; the anthropogenic subterranean freshwaters biome includes water pipes, subterranean canals and flooded mines.
Anthropogenic transformation of the Biosphere
For more than a century, the biosphere has been described in terms of global ecosystem units called
biomes, which are vegetation types like
tropical rainforests
Tropical rainforests are rainforests that occur in areas of tropical rainforest climate in which there is no dry season – all months have an average precipitation of at least 60 mm – and may also be referred to as ''lowland equa ...
and
grasslands
A grassland is an area where the vegetation is dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur natural ...
that are identified in relation to global
climate
Climate is the long-term weather pattern in an area, typically averaged over 30 years. More rigorously, it is the mean and variability of meteorological variables over a time spanning from months to millions of years. Some of the meteorologic ...
patterns. Considering that human populations and their use of land have fundamentally altered global patterns of ecosystem form, process, and biodiversity, anthropogenic biomes provide a framework for integrating human systems with the biosphere in the
Anthropocene
The Anthropocene ( ) is a proposed geological epoch dating from the commencement of significant human impact on Earth's geology and ecosystems, including, but not limited to, anthropogenic climate change.
, neither the International Commissi ...
.
Before 1700
Humans have been altering ecosystems since we have evolved. Evidence suggests that our ancestors were burning land to clear it at one million years ago. 600,000 years ago, humans were using spears to kill horses and other large animals in Great Britain and China. For the past tens of thousands of years, humans have greatly changed the plant and animal life around the globe, from what type of wildlife and plant life dominated to what type of ecosystems dominate.
Examples include Native Americans; they altered the forest, burnt land to clear it, settled in cities, disrupting forests and other ecosystems, and built monuments that required moving large amounts of earth, such as the Cahokia Monuments.
More examples are the civilizations of the ancient world; they mined large amounts of material, made roads, and especially for the Romans, when mining lead, released large amounts of mercury and lead into the air. A recent study showed that nearly three quarters of Earth's land was already inhabited and reshaped by human societies as long as 12,000 years ago.
Agriculture (1700–present)
Humans have been altering ecosystems since before
agriculture
Agriculture or farming is the practice of cultivating plants and livestock. Agriculture was the key development in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that enabled people to ...
first developed, and as the human population has grown and become more technologically advanced over time, the land use for agricultural purposes has increased significantly. The anthropogenic biome in the 1700s, before the
industrial revolution
The Industrial Revolution was the transition to new manufacturing processes in Great Britain, continental Europe, and the United States, that occurred during the period from around 1760 to about 1820–1840. This transition included going f ...
, was made up of mostly wild, untouched land, with no human settlement disturbing the natural state.
[Ellis, E. C. (2011). Anthropogenic transformation of the terrestrial biosphere.''Philosophical Transactions of the Royal Society of London A: Mathematical, Physical and Engineering Sciences'', ''369''(1938), 1010-1035.] In this time period, most of the Earth's ice-free land consisted of wildlands and natural anthromes, and it wasn't until after the industrial revolution in the 19th century that land use for agriculture and human settlements started to increase.
[Ellis, E. C., Klein Goldewijk, K., Siebert, S., Lightman, D., & Ramankutty, N. (2010). Anthropogenic transformation of the biomes, 1700 to 2000. ''Global Ecology and Biogeography'', ''19''(5), 589-606.] With technology advancing and manufacturing processes becoming more efficient, the human population was beginning to thrive, and was subsequently requiring and using more natural resources. By the year 2000, over half of the Earth's ice free land was transformed into rangelands, croplands, villages and dense settlements, which left less than half of the Earth's land untouched.
Anthropogenic changes between 1700 and 1800 were far smaller than those of the following centuries, and as such the rate of change has increased over time. As a result, the 20th century had the fastest rate of anthropogenic ecosystem transformation of the past 300 years.
Land distribution
As the human population steadily increased in numbers throughout history, the use of
natural resource
Natural resources are resources that are drawn from nature and used with few modifications. This includes the sources of valued characteristics such as commercial and industrial use, aesthetic value, scientific interest and cultural value. O ...
s and land began to increase, and the distribution of land used for various agricultural and settlement purposes began to change. The use of land around the world was transformed from its natural state to land used for agriculture, settlements and pastures to sustain the population and its growing needs. The distribution of land among anthromes underwent a shift away from natural anthromes and wildlands towards human-altered anthromes we are familiar with today. Now, the most populated anthromes (dense settlements and villages) account for only a small fraction of the global ice-free land.
From the year 1700-2000, lands used for agriculture and urban settlements increased significantly, however the area occupied by rangelands increased even more rapidly, so that it became the dominant anthrome in the 20th century.
As a result, the biggest global land-use change as a result of the industrial revolution, was the expansion of pastures.
Human population
Following the industrial revolution, the human population experienced a rapid increase. The human
population density
Population density (in agriculture: standing stock or plant density) is a measurement of population per unit land area. It is mostly applied to humans, but sometimes to other living organisms too. It is a key geographical term.Matt RosenberPopul ...
in certain anthromes began to change, shifting away from rural environments to urban settlements, where the population density was much higher.
These changes in population density between areas shifted global patterns of anthrome emergence, and also had wide-spread effects on various ecosystems.
Half of the Earth's population now lives in cities, and most people reside in urban anthromes, with some populations dwelling in smaller cities and towns.
Currently, human populations are expected to grow until at least midcentury,
and the transformation of the Earth's anthromes are expected to follow this growth.
Current state of the anthropogenic biosphere
The present state of the terrestrial biosphere is predominantly anthropogenic.
More than half of the terrestrial biosphere remains unused directly for agriculture or urban settlements, and of these unused lands still remaining, less than half are wildlands. Most of Earth's unused lands are now within the agricultural and settled landscapes of semi-natural, rangeland, cropland and village anthromes.
Major anthromes
Anthromes include dense settlements (urban and mixed settlements), villages, croplands, rangelands and semi-natural lands and have been mapped globally using two different classification systems, viewable on
Google Maps
Google Maps is a web mapping platform and consumer application offered by Google. It offers satellite imagery, aerial photography, street maps, 360° interactive panoramic views of streets ( Street View), real-time traffic conditions, and rou ...
and
Google Earth
Google Earth is a computer program that renders a 3D computer graphics, 3D representation of Earth based primarily on satellite imagery. The program maps the Earth by superimposition, superimposing satellite images, aerial photography, and geog ...
.
There are currently 18 anthropogenic biomes, the most prominent of which are listed below.
[Alessa, L., & Chapin, F. S. (2008). Anthropogenic biomes: a key contribution to earth-system science. ''Trends in Ecology & Evolution'', ''23''(10), 529-531.]
Dense settlements
Dense settlements are the second most densely populated regions in the world.
They are defined as areas with a high population density, though the density can be variable.
The Population density, however, never falls below 100 persons/km, even in the non-urban parts of the dense settlements, and it has been suggested that these areas consist of both the edges of major cities in underdeveloped nations, and the long standing small towns throughout
western Europe
Western Europe is the western region of Europe. The region's countries and territories vary depending on context.
The concept of "the West" appeared in Europe in juxtaposition to "the East" and originally applied to the ancient Mediterranean ...
and
Asia
Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an area ...
.
Most often we think of dense settlements as cities, but dense settlements can also be suburbs, towns and rural settlements with high but
fragmented populations.
[Ellis, E. C. (2013). Sustaining biodiversity and people in the world's anthropogenic biomes. ''Current Opinion in Environmental Sustainability'', ''5''(3), 368-372.]
Croplands
Croplands are another major anthrome throughout the world. Croplands include most of the
cultivated lands of the world, and also about a quarter of global tree cover.
Croplands which are locally
irrigated
Irrigation (also referred to as watering) 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 been devel ...
have the highest human population density,
likely due to the fact that it provides crops with a constant supply on water. This makes harvest time and crop survival more predictable. Croplands that are sustained mainly from the local rainfall are the most extensive of the populated anthromes,
with annual precipitation near 1000 mm in certain areas of the globe. In these areas, there is sufficient water supplied by the climate to support all aspects of life without hardly any irrigation.
However, in dryer areas, this method of agriculture would not be as productive.
Rangelands
Rangelands are a very broad anthropogenic biome group that has been described according to three levels of population density: residential, populated and remote. The Residential rangeland anthrome has two key features: its population density is never below 10 persons per square kilometre, and a substantial portion of its area is used for pasture.
Pastures in rangelands are the most dominant land cover. Bare earth is significant in this anthrome, covering nearly one third of the land for every one square kilometer.
Rangeland anthromes are less altered than croplands, but their alteration tends to increase with population.
Domesticated
Domestication is a sustained multi-generational relationship in which humans assume a significant degree of control over the reproduction and care of another group of organisms to secure a more predictable supply of resources from that group. A ...
grazing livestock are typically adapted to
grassland
A grassland is an area where the vegetation is dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur natur ...
s and
savanna
A savanna or savannah is a mixed woodland-grassland (i.e. grassy woodland) ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to ...
s, so the alteration of these biomes tends to be less noticeable.
Forests
Forested anthromes are dominated by tree cover, and they have high precipitation and minimal human populations, where the population density is usually less than 3 persons/km².
Most populated forests act as
carbon sink
A carbon sink is anything, natural or otherwise, that accumulates and stores some carbon-containing chemical compound for an indefinite period and thereby removes carbon dioxide () from the atmosphere.
Globally, the two most important carbon si ...
s because of the lack of human activity. Without harmful emissions being released in the forests due to human activity, the vegetation is able to utilize carbon dioxide in the atmosphere, and act as a sink. Remote forests are a little different than populated forests because the majority of the vegetation in these forests have been clear-cut for human consumption. Forests are generally cleared to sustain substantial populations of domestic livestock,
and to utilize the lumber.
Indoor
Very few biologists have studied the evolutionary processes at work in indoor environments.
Estimates of the extent of
residential
A residential area is a land used in which housing predominates, as opposed to industrial and commercial areas.
Housing may vary significantly between, and through, residential areas. These include single-family housing, multi-family residen ...
and
commercial
Commercial may refer to:
* a dose of advertising conveyed through media (such as - for example - radio or television)
** Radio advertisement
** Television advertisement
* (adjective for:) commerce, a system of voluntary exchange of products and s ...
buildings range between 1.3% and 6% of global ice-free land area. This area is just as extensive as other small biomes such as flooded grass-lands and tropical
coniferous
Conifers are a group of cone-bearing seed plants, a subset of gymnosperms. Scientifically, they make up the division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single extant class, Pinopsida. All extant ...
forests.
The indoor biome is rapidly expanding, while forest anthromes are shrinking. The indoor biome of
Manhattan
Manhattan (), known regionally as the City, is the most densely populated and geographically smallest of the five boroughs of New York City. The borough is also coextensive with New York County, one of the original counties of the U.S. state ...
is almost three times as large, in terms of its floor space, as is the geographical area of the island itself,
due to the buildings rising up instead of spreading out. Thousands of species live in the indoor biome, many of them preferentially or even obligatorily. The only action that humans take to alter the evolution of the indoor biome is with cleaning practices. The field of indoor biomes will continue to change as long as our culture will change.
Aquatic
Managed aquatic biomes or aquatic anthromes have rarely been studied as such. They range from
fish ponds,
marine shrimp and
benthic farming sites to large tracts of land such as parts of the
Guadalquivir Marshes
The Guadalquivir Marshes (in es, Marismas del Guadalquivir or simply ''Las Marismas'') are a natural region of marshy lowlands on the lower Guadalquivir River.
The ''Las Marismas'' zone forms a large part of the province of Huelva, province o ...
in
Andalusia
Andalusia (, ; es, Andalucía ) is the southernmost Autonomous communities of Spain, autonomous community in Peninsular Spain. It is the most populous and the second-largest autonomous community in the country. It is officially recognised as a ...
, Spain.
Ecosystem approach to Aquaculture management and biodiversity conservation in a Mediterranean coastal wetland: case study of Doniana marshes (Andalucia, Spain)
', United Nations Environmental Program / Mediterranean Action Plan, Tunis 2012.
Implications of an anthropogenic biosphere
Humans have fundamentally altered global patterns of biodiversity and ecosystem processes.
It is no longer possible to explain or predict ecological patterns or processes across the Earth without considering the human role.
[Ellis, E. C. (2015). Ecology in an Anthropogenic Biosphere. ''Ecological Monographs''.] Human societies began transforming terrestrial ecology more than 50 000 years ago,
and
evolution
Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...
ary evidence has been presented demonstrating that the ultimate causes of human transformation of the biosphere are social and cultural, not biological, chemical, or physical.
Anthropogenic biomes offer a new way forward by acknowledging human influence on global ecosystems and moving us toward models and investigations of the terrestrial biosphere that integrate human and ecological systems.
Challenges facing biodiversity in the anthropogenic biosphere
Extinctions
Over the past century, anthrome extent and land use intensity increased rapidly together with growing human populations, leaving wildlands without human population or land use in less than one quarter of the terrestrial biosphere.
This massive transformation of Earth's ecosystems for human use has occurred with enhanced rates of species
extinction
Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...
s. Humans are directly causing species extinctions, especially of
megafauna
In terrestrial zoology, the megafauna (from Greek μέγας ''megas'' "large" and New Latin ''fauna'' "animal life") comprises the large or giant animals of an area, habitat, or geological period, extinct and/or extant. The most common threshold ...
, by reducing, fragmenting and transforming native habitats and by overexploiting individual species.
Current rates of extinctions vary greatly by taxa, with mammals, reptiles and amphibians especially threatened; however there is growing evidence that viable populations of many, if not most native taxa, especially plants, may be sustainable within anthromes.
With the exception of especially vulnerable taxa, the majority of native species may be capable of maintaining viable populations in anthromes.
Conservation
Anthromes present an alternative view of the terrestrial biosphere by characterizing the
diversity
Diversity, diversify, or diverse may refer to:
Business
*Diversity (business), the inclusion of people of different identities (ethnicity, gender, age) in the workforce
*Diversity marketing, marketing communication targeting diverse customers
* ...
of global ecological land cover patterns created and sustained by human population densities and land use while also incorporating their relationships with
biotic communities.
[Martin, L. J., Quinn, J. E., Ellis, E. C., Shaw, M. R., Dorning, M. A., Hallett, L. M., ... & Michel, N. L. (2014). Conservation opportunities across the world's anthromes. ''Diversity and distributions'', ''20''(7), 745-755.] Biome
A biome () is a biogeographical unit consisting of a biological community that has formed in response to the physical environment in which they are found and a shared regional climate. Biomes may span more than one continent. Biome is a broader ...
s and
ecoregion
An ecoregion (ecological region) or ecozone (ecological zone) is an ecologically and geographically defined area that is smaller than a bioregion, which in turn is smaller than a biogeographic realm. Ecoregions cover relatively large areas of l ...
s are limited in that they reduce human influences, and an increasing number of
conservation
Conservation is the preservation or efficient use of resources, or the conservation of various quantities under physical laws.
Conservation may also refer to:
Environment and natural resources
* Nature conservation, the protection and managem ...
biologists have argued that biodiversity conservation must be extended to
habitat
In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...
s directly shaped by humans. Within anthromes, including densely populated anthromes, humans rarely use all available land. As a result, anthromes are generally mosaics of heavily used lands and less intensively used lands.
Protected areas and
biodiversity
Biodiversity or biological diversity is the variety and variability of life on Earth. Biodiversity is a measure of variation at the genetic (''genetic variability''), species (''species diversity''), and ecosystem (''ecosystem diversity'') l ...
hotspots are not distributed equally across anthromes. Less populated anthromes contain a greater proportion of protected areas. While 23.4% of remote woodland anthrome is protected, only 2.3% of irrigated village anthrome is protected.
There is increasing evidence that suggests that biodiversity conservation can be effective in both densely and sparsely settled anthromes. Land sharing and land sparing are increasingly seen as conservation strategies.
See also
*
Anthropocene
The Anthropocene ( ) is a proposed geological epoch dating from the commencement of significant human impact on Earth's geology and ecosystems, including, but not limited to, anthropogenic climate change.
, neither the International Commissi ...
*
Novel ecosystem Novel ecosystems are human-built, modified, or engineered niches of the Anthropocene. They exist in places that have been altered in structure and function by human agency. Novel ecosystems are part of the human environment and niche (including u ...
*
Technoecosystem
*
Technodiversity
References
{{Reflist
External links
Putting the "Me" in Biome : Educational Resource at National GeographicAnthropogenic Biomes at NASAAnthropogenic Biomes project web site (with maps, educational materials, downloadable data)
Anthropocene
Biomes
Habitats
Urban planning
Human habitats
Human impact on the environment