Ethiopian montane forests | |
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Ecology | |
Realm | Afrotropical |
Biome | tropical and subtropical moist broadleaf forests |
Borders | |
Geography | |
Area | 67,663 km2 (26,125 sq mi) |
Country | Ethiopia |
Elevation | 1000 – 3000 m |
Conservation | |
Conservation status | Critical/endangered (WWF, 2001), [1] Nature Imperiled (One Earth, 2017) [2] |
Protected | 7,659 km2 (11%) [3] |
The Ethiopian montane forests is a tropical moist broadleaf forest ecoregion in Ethiopia. It covers the southwestern and southeastern portions of the Ethiopian Highlands. The ecoregion includes distinctive Afromontane evergreen forests. The ecoregion's biodiversity is threatened by deforestation, conversion to agriculture, and overgrazing. [2]
The Ethiopian montane forests lie in the southwestern and southeastern Ethiopian Highlands. The southwestern portion is bounded at lower elevations by the East Sudanian savanna, and the southeastern portion transitions to the Somali Acacia–Commiphora bushlands and thickets at lower elevations. [2]
At higher elevations they transition to the Ethiopian montane moorlands. [1] The Ethiopian montane grasslands and woodlands ecoregion covers most of the rest of the highlands, and includes drier montane Afromontane forests, woodlands, and grasslands to the north and east. [2]
In the 1983 Vegetation Map of Africa, Frank White identified three vegetation types in the Ethiopian highlands – "Evergreen and semi-evergreen bushland and thicket - East African" from 1000 to 1800 meters elevation, "Undifferentiated montane vegetation (A) Afromontane" from 1,800 to about 3800 meters elevation, and "Altimontane vegetation in tropical Africa" above 3,800 meters elevation. [4] [5] The 2001 Terrestrial Ecoregions of the World system adopted by the World Wildlife Fund followed White's vegetation types in the Ethiopian Highlands, with the "Ethiopian montane forests" ecoregion corresponding to White's "Evergreen and semi-evergreen bushland and thicket - East African", the "Ethiopian montane grasslands and woodlands" to the "Undifferentiated montane vegetation (A) Afromontane", and the Ethiopian montane moorlands to White's "Altimontane vegetation in tropical Africa". [6] [7]
In 2017 Eric Dinerstein et al. revised the ecoregion system in the highlands, following the map of potential natural vegetation of eastern Africa developed by VECEA. [8] [9] The revised ecoregion boundaries were adopted by One Earth, [2] and later by the WWF. [1]
Moisture-bearing winds from the Red Sea provide rainfall throughout the year. The highlands generate orographic precipitation, and are generally cooler and more humid than the lower-elevation deserts and dry shrublands that bound the highlands on the east and south. Orographic effects create fog and cloud cover which keep humidity high and help sustain forests. Southwesterly winds bring rainfall from May to October. Average annual rainfall varies with location, from 600 to 1500 mm. The southern and southwestern portions of the ecoregion generally have higher rainfall. [1]
The Ethiopian montane forests are composed of two main plant communities, Afromontane rain forest (aka moist evergreen Afromontane forest) and Afromontane transitional rain forest. [5] [2] The ecoregion's Afromontane flora includes species distinct to Africa's highland regions, often mixed with typical lowland species. In most of the ecoregion the natural vegetation has been heavily altered by livestock grazing, conversion to agriculture, and plantations of exotic trees. [1]
Afromontane forests grow between (1500-) 1800 and 2600 (-3000) meters elevation. The largest block of Afromontane forest is in the southwestern highlands. There is a smaller bloc in the eastern highlands, which includes the Harenna Forest on the southern slope of the Bale Mountains. [5] Characteristic trees of the Afromontane rain forests include Diospyros abyssinica , Mitragyna rubrostipulata , Macaranga capensis , Ochna holstii , Olea capensis , Aningeria adolfi-friederici , Prunus africana , and Syzygium guineense , along with the tree fern Alsophila manniana . [10]
In the Harenna Forest, lower montane forests grow between 1900 and 2300 meters elevation. Middle montane forests occur between 2300 and 2800 meters. Upper montane forests, which include forests dominated by Hagenia abyssinica and extensive stands of the bamboo Yushania alpina , grow from 2800 to 3250 meters elevation. [11] At lower elevations, the Harenna Forest transitions to a distinct woodland community, with an open canopy of Warburgia ugandensis, Croton macrostachyus, Syzygium guineense , and Afrocarpus gracilior , and wild coffee (Coffea arabica) as the dominant understory shrub. [1]
Afromontane transitional rain forests grow on the western slopes of the southwestern highlands, as low as 450 meters elevation and up to 1,500 meters elevation. Transitional rain forests between 450 and 650 meters elevation are typically semi-deciduous, while forests at higher elevations are mostly evergreen. [5] Typical species include bastard white stinkwood ( Celtis gomphophylla ), forest fever berry ( Croton sylvaticus ), giant diospyros ( Diospyros abyssinica ), forest sandpaper fig Ficus exasperata ), Manilkara butugi , and mvule ( Milicia excelsa ). [10]
Kolla is an open woodland found at lower elevations, in the transition to the lowland savannas and dry woodlands. Characteristic trees are species of Terminalia, Commiphora, Boswellia , and Acacia . [1]
Native birds include Harwood's spurfowl (Pternistis harwoodi), Ruspoli's turaco (Menelikornis ruspolii), and yellow-throated seedeater (Crithagra flavigula), which are endemic to the Ethiopian Highlands. [1]
11% of the ecoregion is in protected areas. [3] These include Bale Mountains National Park, Chebera Churchura National Park, Didessa National Park, Bonga Forest Reserve, and the proposed Gebre Dima, Harena-Kokosa, and Sele Anderacha National Forest Priority Areas. [12]
Only 1% of the area outside protected areas is covered in relatively intact forest. [3] One Earth assesses the ecoregion as 'imperiled', with "the amount of protected and unprotected natural habitat remaining is less than or equal to 20%. Achieving half protected is not possible in the short term and efforts should focus on conserving remaining, native habitat fragments.". [2]
The Madagascar subhumid forests are a tropical moist broadleaf forest ecoregion that covers most of the Central Highlands of the island of Madagascar. They are included in the WWF's Global 200 list of outstanding ecoregions. Most of the original habitats have been lost due to human pressure.
The Ethiopian Highlands is a rugged mass of mountains in Ethiopia in Northeast 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. It is the only country in the region with such a high elevated surface. This elevated surface is bisected diagonally by the Great East African Rift System which extends from Syria to Mozambique across the East African Lakes. Most of the Ethiopian Highlands are part of central and northern Ethiopia, and its northernmost portion reaches into Eritrea.
The Maputaland-Pondoland bushland and thickets is one of the ecoregions of South Africa. It consists of the montane shrubland biome.
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.
The Sri Lanka dry-zone dry evergreen forests are a tropical dry broadleaf forest ecoregion of the island of Sri Lanka.
The Coastal forests of eastern Africa, also known as the East African Coastal Forests or Zanzibar–Inhambane forests, is a tropical moist forest region along the east coast of Africa. The region was designated a biodiversity hotspot by Conservation International.
The Southwestern Arabian montane woodlands is a xeric woodland ecoregion in the southwestern Arabian Peninsula.
The Cameroonian Highlands forests, also known as the Cameroon Highlands forests, are a montane tropical moist broadleaf forest ecoregion located on the range of mountains that runs inland from the Gulf of Guinea and forms the border between Cameroon and Nigeria. This is an area of forest and grassland which has become more populous as land is cleared for agriculture.
The Mount Cameroon and Bioko montane forests is a tropical moist broadleaf forest ecoregion in central Africa. It occupies the upper slopes of coastal Mount Cameroon in Cameroon, and the mountains of nearby Bioko island in Equatorial Guinea.
The Harenna Forest is a montane tropical evergreen forest in Ethiopia's Bale Mountains. The forest covers the southern slope of the mountains, extending from 1450 to 3200 meters in elevation. The Bale Mountains are in Ethiopia's Oromia Region and form the southwestern portion of the Ethiopian Highlands.
The Southern Zanzibar–Inhambane coastal forest mosaic, also known as the Southern Swahili coastal forests and woodlands, is a tropical moist broadleaf forest ecoregion of eastern Africa. It is a southern variation of Northern Zanzibar-Inhambane coastal forest mosaic. The ecoregion supports habitats of forest, savanna and swamps. The southern portion of the ecoregion is not as well studied due to the 1977-1992 civil war in Mozambique.
The Sanetti Plateau is a major plateau of the Ethiopian Highlands, in the Oromia Region of Ethiopia. The plateau is the highest part of the Bale Mountains, and is located within Bale Mountains National Park.
The Ethiopian montane grasslands and woodlands is a montane grasslands and shrublands ecoregion in Ethiopia. It occupies the middle elevations of the Ethiopian Highlands, between the high-elevation Ethiopian montane moorlands and lowland woodlands, savannas, shrublands, and thickets.
The Huon Peninsula montane rain forests is a tropical moist forest ecoregion in New Guinea. The ecoregion covers the mountains of northeastern New Guinea's Huon Peninsula.
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.
Northern Zanzibar–Inhambane coastal forest mosaic, also known as the Northern Swahili coastal forests and woodlands, is a tropical moist broadleaf forest ecoregion of coastal East Africa. The ecoregion includes a variety of habitats, including forest, savanna and swamps.
The Ruwenzori-Virunga montane moorlands is a montane grasslands and shrublands ecoregion of the Rwenzori Mountains and Virunga Mountains in central Africa.
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.
The Southwestern Arabian foothills savanna, also known as the Southwestern Arabian Escarpment shrublands and woodlands, is a desert and xeric shrubland ecoregion of the southern Arabian Peninsula, covering portions of Saudi Arabia, Yemen, and Oman.
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.