Anthropogenic biome
[6] In a recent global ecosystem classification, anthropogenic biomes have 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.
600,000 years ago, humans were using spears to kill horses and other large animals in Great Britain and China.
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.
The anthropogenic biome in the 1700s, before the industrial revolution, was made up of mostly wild, untouched land, with no human settlement disturbing the natural state.
[10] 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.
Now, the most populated anthromes (dense settlements and villages) account for only a small fraction of the global ice-free land.
[9] These changes in population density between areas shifted global patterns of anthrome emergence, and also had wide-spread effects on various ecosystems.
Most of Earth's unused lands are now within the agricultural and settled landscapes of semi-natural, rangeland, cropland and village anthromes.
[12] 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 and Asia.
[12] Croplands which are locally irrigated have the highest human population density,[12] likely due to the fact that it provides crops with a constant supply on water.
Croplands that are sustained mainly from the local rainfall are the most extensive of the populated anthromes,[12] with annual precipitation near 1000 mm in certain areas of the globe.
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.
[9] Domesticated grazing livestock are typically adapted to grasslands and savannas, so the alteration of these biomes tends to be less noticeable.
[12] Many cultured woodlands are secondary forests that act as carbon sinks as a result of ongoing regrowth of woody vegetation.
The indoor biome of Manhattan 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.
They range from fish ponds, marine shrimp and benthic farming sites to large tracts of land such as parts of the Guadalquivir Marshes in Andalusia, Spain.
[13] This massive transformation of Earth's ecosystems for human use has occurred with enhanced rates of species extinctions.
[13] With the exception of especially vulnerable taxa, the majority of native species may be capable of maintaining viable populations in anthromes.
[19] There is increasing evidence that suggests that biodiversity conservation can be effective in both densely and sparsely settled anthromes.
