Afromontane

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Afromontane Zones. I. West African and Cameroon highlands, II. Ethiopian and Arabian highlands, III. Western (Albertine) Rift, IV. Eastern Rift. V. Southern Rift, VI. Eastern Highlands, VII. Drakensberg Afromontane Zones (transparent).png
Afromontane Zones. I. West African and Cameroon highlands, II. Ethiopian and Arabian highlands, III. Western (Albertine) Rift, IV. Eastern Rift. V. Southern Rift, VI. Eastern Highlands, VII. Drakensberg

The Afromontane regions are subregions of the Afrotropical realm, one of the Earth's eight biogeographic realms, covering the plant and animal species found in the mountains of Africa and the southern Arabian Peninsula. The Afromontane regions of Africa are discontinuous, separated from each other by lower-lying areas, and are sometimes referred to as the Afromontane archipelago, as their distribution is analogous to a series of sky islands.

Contents

Geography

Afromontane communities occur above 1,500–2,000 metres (4,900–6,600 ft) elevation near the equator, and as low as 300 metres (980 ft) elevation in the Knysna-Amatole montane forests of South Africa. Afromontane forests are generally cooler and more humid than the surrounding lowlands.

The Afromontane archipelago mostly follows the East African Rift from the Red Sea to Zimbabwe, with the largest areas in the Ethiopian Highlands, the Albertine Rift Mountains of Uganda, Rwanda, Burundi, Democratic Republic of the Congo, and Tanzania, and the Eastern Arc highlands of Kenya and Tanzania. Other Afromontane regions include the Drakensberg range of southern Africa, the Cameroon Highlands, and the Cameroon Line volcanoes, including Mount Cameroon, Bioko, and São Tomé.

Flora

Although some Afromontane enclaves are widely separated, they share a similar mix of plant species which are often distinct from the surrounding lowland regions. Podocarps, of genera Podocarpus and Afrocarpus , are a characteristic tree, along with Prunus africana , Hagenia abyssinica , Juniperus procera , and Olea spp.. In the higher mountains, the Afromontane forest or woodland zone transitions to a higher Afroalpine zone of grasslands, shrublands, or moorlands.

The plant families Curtisiaceae and Oliniaceae are Afromontane endemics and family Barbeyaceae is a near-endemic. The tree genera Afrocrania, Balthasaria, Curtisia, Ficalhoa, Hagenia, Kiggelaria, Leucosidea, Platypterocarpus, Trichocladus, Widdringtonia , and Xymalos are Afromontane endemics or near-endemics, as are the plant genera Ardisiandra, Cincinnobotrys, and Stapfiella .

Distribution

Eastern Afromontane biodiversity hotspot Eastern Afromontane Biodiversity Hotspot (cropped).png
Eastern Afromontane biodiversity hotspot

In South Africa, Afromontane forests cover only 0.5% of the country's land area. The Afromontane forests occur along the mountainous arc of the Drakensberg Range, from Limpopo Province in the northeast to the Western Cape Province in the southwest. The Afromontane forests generally occur in well-watered areas, including ravines and south-facing slopes. The Afromontane forests are intolerant of fire, and the frequent fires of the surrounding fynbos, savanna, and grassland limit the expansion of the forests. Despite their small area, the Afromontane forests of South Africa produce valuable timber, particularly the real yellowwood (Podocarpus latifolius), Outeniqua yellowwood (Afrocarpus falcatus), and stinkwood (Ocotea bullata).

Afromontane ecoregions

Tropical and subtropical moist broadleaf forests
Montane grasslands, shrublands, and woodlands
Deserts and xeric shrublands

Related Research Articles

Woodland Land covered in trees

A woodland is, in the broad sense, land covered with trees, or in a narrow sense, synonymous with wood, a low-density forest forming open habitats with plenty of sunlight and limited shade. Woodlands may support an understory of shrubs and herbaceous plants including grasses. Woodland may form a transition to shrubland under drier conditions or during early stages of primary or secondary succession. Higher-density areas of trees with a largely closed canopy that provides extensive and nearly continuous shade are often referred to as forests.

The Global 200 is the list of ecoregions identified by WWF, the global conservation organization, as priorities for conservation. According to WWF, an ecoregion is defined as a "relatively large unit of land or water containing a characteristic set of natural communities that share a large majority of their species dynamics, and environmental conditions". So, for example, based on their levels of endemism, Madagascar gets multiple listings, ancient Lake Baikal gets one, and the North American Great Lakes get none.

Afrotropical realm One of the Earths eight [[biogeographic realm]]s

The Afrotropical realm is one of the Earth's eight biogeographic realms. It includes Africa south of the Sahara Desert, the majority 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 known as the Ethiopian Zone or Ethiopian Region.

Ethiopian Highlands mountain range

The Ethiopian Highlands is a rugged mass of mountains in Ethiopia, situated in northeast part of Africa. It forms the largest continuous area of its elevation in the continent, with little of its surface falling below 1,500 m (4,900 ft), while the summits reach heights of up to 4,550 m (14,930 ft). It is sometimes called the Roof of Africa due to its height and large area. Most of the Ethiopian Highlands are part of central and northern Ethiopia, and its northernmost portion reaches into Eritrea.

Knysna-Amatole montane forests Ecoregion of the tropical and subtropical moist broadleaf forests biome in South Africa

The Knysna-Amatole montane forests ecoregion, of the tropical and subtropical moist broadleaf forests biome, is in South Africa. It covers an Afromontane area of 3,100 square kilometres (1,200 sq mi) in the Eastern Cape and Western Cape provinces.

Forest-savanna mosaic is a transitory ecotone between the tropical moist broadleaf forests of Equatorial Africa and the drier savannas and open woodlands to the north and south of the forest belt. The forest-savanna mosaic consists of drier forests, often gallery forest, interspersed with savannas and open grasslands.

<i>Hagenia</i> genus of plants

Hagenia abyssinica is a species of flowering plant native to the high-elevation Afromontane regions of central and eastern Africa. It also has a disjunct distribution in the high mountains of East Africa from Sudan and Ethiopia in the north, through Kenya, Uganda, Rwanda, Burundi, Democratic Republic of Congo, and Tanzania, to Malawi and Zambia in the south.

Ptychadena porosissima is a species of frog in the family Ptychadenidae. It is found in Angola, Democratic Republic of the Congo, Ethiopia, Kenya, Malawi, Rwanda, South Africa, Swaziland, Tanzania, Uganda, Zambia, Zimbabwe, possibly Burundi, possibly Lesotho, and possibly Mozambique. Its natural habitats are temperate forest, subtropical or tropical moist montane forest, moist savanna, subtropical or tropical moist shrubland, temperate grassland, subtropical or tropical seasonally wet or flooded lowland grassland, subtropical or tropical high-altitude grassland, swamps, intermittent freshwater marshes, pastureland, rural gardens, and heavily degraded former forest.

Fan-tailed widowbird species of bird

The fan-tailed widowbird, also known as the red-shouldered widowbird, is a species of bird in the family Ploceidae, which is native to grassy and swampy areas of the tropical and subtropical Afrotropics.

Climbing shrew species of mammal

The climbing shrew is a species of mammal in the family Soricidae, which is found in subtropical Africa. It is found in Angola, Benin, Burundi, Cameroon, Central African Republic, Republic of the Congo, Democratic Republic of the Congo, Ivory Coast, Ethiopia, Ghana, Guinea, Kenya, Liberia, Malawi, Mozambique, Nigeria, Rwanda, Sierra Leone, South Sudan, Tanzania, Togo, Uganda, Zambia, and Zimbabwe. Its natural habitats are subtropical or tropical moist lowland forest, subtropical or tropical moist montane forest, and moist savanna.

The Southern Highlands is a highland region in southwestern Tanzania, at the northern end of Lake Malawi. The highlands include portions of Mbeya, Njombe, Rukwa, Ruvuma, and Songwe regions, bordering Malawi, Mozambique, and Zambia. Mbeya is the largest city in the highlands.

Southern Afrotemperate Forest Main indigenous forest-type in the south-western part of South Africa

Southern Afrotemperate Forest is a kind of tall, shady, multilayered indigenous South African forest. This is the main forest-type in the south-western part of South Africa, naturally extending from the Cape Peninsula in the west, as far as Port Elizabeth in the east. In this range, it usually occurs in small forest pockets, surrounded by fynbos vegetation.

East African montane forests Ecoregion (WWF)

The East African montane forests is a montane tropical moist forest ecoregion of eastern Africa. The ecoregion comprises several separate areas above 2000 meters in the mountains of South Sudan, Uganda, Kenya, and Tanzania.

Rwenzori-Virunga montane moorlands montane ecoregion in central Africa

The Ruwenzori-Virunga montane moorlands is a montane grasslands and shrublands ecoregion of central Africa.

Southern Rift montane forest-grassland mosaic Ecoregion in Malawi, Tanzania, and Zambia

The South Malawi montane forest-grassland mosaic is a montane grasslands and shrublands ecoregion of Tanzania, Malawi, Mozambique, and Zambia.

Northern Acacia-Commiphora bushlands and thickets Ecoregion (WWF)

The Northern Acacia-Commiphora bushlands and thickets are a tropical grasslands, savannas, and shrublands ecoregion in eastern Africa. The ecoregion is mostly located in Kenya, extending north into southeastern South Sudan, northeastern Uganda, and southwestern Ethiopia, and south into Tanzania along the Kenya-Tanzania border.

Somali Acacia-Commiphora bushlands and thickets Ecoregion (WWF)

The Somali Acacia-Commiphora bushlands and thickets is a semi-arid tropical grasslands, savannas, and shrublands ecoregion in the Horn of Africa. It is home to diverse communities of plants and animals, including several endemic species.

Victoria Basin forest-savanna mosaic Ecoregion (WWF)

The Victoria Basin forest-grassland mosaic is an ecoregion that lies mostly in Uganda and extends into neighboring countries. The ecoregion is centered north and west of Lake Victoria, with an outlier on the border of Ethiopia and South Sudan.

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