Montane grasslands and shrublands
Encyclopedia
Montane grasslands and shrublands is a biome
defined by the World Wildlife Fund. The biome includes high altitude
(montane
, subalpine
, and alpine
) grassland
s and shrubland
s around the world.
Montane grasslands and shrublands located above the tree line are commonly known as alpine tundra
, which occurs in mountain
regions around the world. Below the tree line are subalpine and montane grasslands and shrublands. Stunted subalpine forests are known as krummholz
, and occur just below the tree line, where harsh, windy conditions and poor soils create dwarfed and twisted forest
s of slow-growing trees.
Montane grasslands and shrublands, particularly in subtropical and tropical regions, often evolved as virtual islands, separated from other montane regions by warmer, lower elevation regions, and are frequently home to many distinctive and endemic
plants which evolved in response to the cool, wet climate
and abundant tropical sunlight. Characteristic plants of these habitats display adaptations such as rosette structures, waxy surfaces, and hairy leaves. A unique feature of many wet tropical montane regions is the presence of giant rosette plants from a variety of plant families, such as Lobelia
(Afrotropic
), Puya
(Neotropic
), Cyathea
(New Guinea
), and Argyroxiphium
(Hawaii
).
The most extensive montane grasslands and shrublands occur in the Neotropic
Paramo
of the Andes Mountains. This biome also occurs in the mountains of east
and central Africa
, Mount Kinabalu
of Borneo
, highest elevations of the Western Ghats
in South India
and the Central Highlands of New Guinea
.
Where conditions are drier, one finds montane grasslands, savannas, and woodlands, like the Ethiopian Highlands
, and montane steppe
s, like the steppes of the Tibetan Plateau
.
Biome
Biomes are climatically and geographically defined as similar climatic conditions on the Earth, such as communities of plants, animals, and soil organisms, and are often referred to as ecosystems. Some parts of the earth have more or less the same kind of abiotic and biotic factors spread over a...
defined by the World Wildlife Fund. The biome includes high altitude
Altitude
Altitude or height is defined based on the context in which it is used . As a general definition, altitude is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. The reference datum also often varies according to the context...
(montane
Montane
In biogeography, montane is the highland area located below the subalpine zone. Montane regions generally have cooler temperatures and often have higher rainfall than the adjacent lowland regions, and are frequently home to distinct communities of plants and animals.The term "montane" means "of the...
, subalpine
Subalpine
The subalpine zone is the biotic zone immediately below tree line around the world. Species that occur in this zone depend on the location of the zone on the Earth, for example, Snow Gum in Australia, or Subalpine Larch, Mountain Hemlock and Subalpine Fir in western North America.Trees in the...
, and alpine
Alpine climate
Alpine climate is the average weather for a region above the tree line. This climate is also referred to as mountain climate or highland climate....
) grassland
Grassland
Grasslands are areas where the vegetation is dominated by grasses and other herbaceous plants . However, sedge and rush families can also be found. Grasslands occur naturally on all continents except Antarctica...
s and shrubland
Shrubland
Shrubland, scrubland, scrub or brush is a plant community characterized by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity...
s around the world.
Montane grasslands and shrublands located above the tree line are commonly known as alpine tundra
Alpine tundra
Alpine tundra is a natural region that does not contain trees because it is at high altitude. Alpine tundra is distinguished from arctic tundra, because alpine soils are generally better drained than arctic soils...
, which occurs in mountain
Mountain
Image:Himalaya_annotated.jpg|thumb|right|The Himalayan mountain range with Mount Everestrect 58 14 160 49 Chomo Lonzorect 200 28 335 52 Makalurect 378 24 566 45 Mount Everestrect 188 581 920 656 Tibetan Plateaurect 250 406 340 427 Rong River...
regions around the world. Below the tree line are subalpine and montane grasslands and shrublands. Stunted subalpine forests are known as krummholz
Krummholz
Krummholz or Krumholtz formation — also called Knieholz — is a particular feature of subarctic and subalpine tree line landscapes. Continual exposure to fierce, freezing winds causes vegetation to become stunted and deformed...
, and occur just below the tree line, where harsh, windy conditions and poor soils create dwarfed and twisted forest
Forest
A forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...
s of slow-growing trees.
Montane grasslands and shrublands, particularly in subtropical and tropical regions, often evolved as virtual islands, separated from other montane regions by warmer, lower elevation regions, and are frequently home to many distinctive and endemic
Endemic (ecology)
Endemism is the ecological state of being unique to a defined geographic location, such as an island, nation or other defined zone, or habitat type; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, all species of lemur are endemic to the...
plants which evolved in response to the cool, wet climate
Climate
Climate encompasses the statistics of temperature, humidity, atmospheric pressure, wind, rainfall, atmospheric particle count and other meteorological elemental measurements in a given region over long periods...
and abundant tropical sunlight. Characteristic plants of these habitats display adaptations such as rosette structures, waxy surfaces, and hairy leaves. A unique feature of many wet tropical montane regions is the presence of giant rosette plants from a variety of plant families, such as Lobelia
Lobelia
Lobelia is a genus of flowering plant comprising 360–400 species, with a subcosmopolitan distribution primarily in tropical to warm temperate regions of the world, a few species extending into cooler temperate regions...
(Afrotropic
Afrotropic
The Afrotropic is one of the Earth's eight ecozones. It includes Africa south of the Sahara Desert, the southern and eastern fringes of the Arabian Peninsula, the island of Madagascar, southern Iran and extreme southwestern Pakistan, and the islands of the western Indian Ocean. It was formerly...
), Puya
Puya (genus)
Puya is a genus of the botanical family Bromeliaceae, subfamily Pitcairnioideae. These terrestrial plants are native to the Andes Mountains of South America and southern Central America...
(Neotropic
Neotropic
In biogeography, the Neotropic or Neotropical zone is one of the eight terrestrial ecozones. This ecozone includes South and Central America, the Mexican lowlands, the Caribbean islands, and southern Florida, because these regions share a large number of plant and animal groups.It is sometimes used...
), Cyathea
Cyathea
Cyathea is a genus of tree ferns, the type genus of the fern order Cyatheales. They are mostly terrestrial ferns, usually with a single tall stem. Rarely, the trunk may be branched or creeping. Many species also develop a fibrous mass of roots at the base of the trunk. The genus has a pantropical...
(New Guinea
New Guinea
New Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...
), and Argyroxiphium
Argyroxiphium
Argyroxiphium is a small genus of five species in the sunflower family, Asteraceae. Its members are known by the common name of silversword or greensword due to their long, narrow leaves and the silvery hairs on some species. It belongs to a larger radiation of over 50 species, including the...
(Hawaii
Hawaii
Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...
).
The most extensive montane grasslands and shrublands occur in the Neotropic
Neotropic
In biogeography, the Neotropic or Neotropical zone is one of the eight terrestrial ecozones. This ecozone includes South and Central America, the Mexican lowlands, the Caribbean islands, and southern Florida, because these regions share a large number of plant and animal groups.It is sometimes used...
Paramo
Páramo
The term páramo can refer to a variety of ecosystems. Some ecologists describe the páramo broadly as “all high, tropical, montane vegetation above the continuous timberline”. A more narrow term classifies the páramo according to its regional placement - specifically located in “the northern Andes...
of the Andes Mountains. This biome also occurs in the mountains of east
East Africa
East Africa or Eastern Africa is the easterly region of the African continent, variably defined by geography or geopolitics. In the UN scheme of geographic regions, 19 territories constitute Eastern Africa:...
and central Africa
Central Africa
Central Africa is a core region of the African continent which includes Burundi, the Central African Republic, Chad, the Democratic Republic of the Congo, and Rwanda....
, Mount Kinabalu
Mount Kinabalu
Mount Kinabalu is a prominent mountain on the island of Borneo in Southeast Asia. It is located in the East Malaysian state of Sabah and is protected as Kinabalu National Park, a World Heritage Site. Kinabalu is the tallest peak in Borneo's Crocker Range and is the tallest mountain in the Malay...
of Borneo
Borneo
Borneo is the third largest island in the world and is located north of Java Island, Indonesia, at the geographic centre of Maritime Southeast Asia....
, highest elevations of the Western Ghats
Western Ghats
The Western Ghats, Western Ghauts or the Sahyādri is a mountain range along the western side of India. It runs north to south along the western edge of the Deccan Plateau, and separates the plateau from a narrow coastal plain along the Arabian Sea. The Western Ghats block rainfall to the Deccan...
in South India
South India
South India is the area encompassing India's states of Andhra Pradesh, Karnataka, Kerala and Tamil Nadu as well as the union territories of Lakshadweep and Pondicherry, occupying 19.31% of India's area...
and the Central Highlands of New Guinea
New Guinea
New Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...
.
Where conditions are drier, one finds montane grasslands, savannas, and woodlands, like the Ethiopian Highlands
Ethiopian Highlands
The Ethiopian Highlands are a rugged mass of mountains in Ethiopia, Eritrea , and northern Somalia in the Horn of Africa...
, and montane steppe
Steppe
In physical geography, steppe is an ecoregion, in the montane grasslands and shrublands and temperate grasslands, savannas, and shrublands biomes, characterized by grassland plains without trees apart from those near rivers and lakes...
s, like the steppes of the Tibetan Plateau
Tibetan Plateau
The Tibetan Plateau , also known as the Qinghai–Tibetan Plateau is a vast, elevated plateau in Central Asia covering most of the Tibet Autonomous Region and Qinghai, in addition to smaller portions of western Sichuan, southwestern Gansu, and northern Yunnan in Western China and Ladakh in...
.