Afromontane
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.
Geography
Afromontane communities occur above elevation near the equator, and as low as 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, Kuloa, Leucosidea, Platypterocarpus, Trichocladus, ''Widdringtonia, and Xymalos are Afromontane endemics or near-endemics, as are the plant genera Ardisiandra, Cincinnobotrys, and Stapfiella''.
Plant communities
Afromontane areas have a wide range of plant communities, including intermediate types. These include:- Afromontane rain forest. Afromontane rain forest is found on wetter slopes from southern Ethiopia to Malawi, mostly between 1200 and 2500 meters elevation. It occurs on wetter slopes where average annual rainfall is from 1250 to 2500 mm, or higher. Elevation and location varies somewhat based on distance from the equator or from the sea, and the size and configuration of the highland where it occurs. Mature rain forests generally have an upper stratum of trees 25 to 45 meters high, a middle stratum 14 to 30 meters high, a lower stratum 6 to 15 meters high, a shrub layer of 3 to 6 meters high, and a sparse herbaceous ground layer. The tree crowns of the upper strata are typically open, and the middle strata may be continuous but rarely forms a dense canopy, while the lower tree stratum is typically dense. Most trees are evergreen. Afromontane rain forests can be similar in structure to lowland Guineo-Congolian rain forests, but the species mostly differ from lowland forests. Typical trees include Aningeria adolfi-friederici, Cola greenwayi, Cylicomorpha parviflora, Diospyros abyssinica, Drypetes gerrardii, Entandrophragma excelsum, Ficalhoa laurifolia, Gambeya gorungosana, Kuloa usambarensis, Mitragyna rubrostipulata, Myrianthus holstii, Ochna holstii, Olea capensis, Parinari excelsa, Podocarpus milanjianus, Prunus africana, Strombosia scheffleri, Syzygium guineense subsp. afromontanum, Tabernaemontana johnstonii, and Xymalos monospora. Tree ferns, lianas, and epiphytes, including ferns, mosses, and species of Begonia, Impatiens, Streptocarpus, and Peperomia, are abundant.
Distribution
Afromontane ecoregions
;Tropical and subtropical moist broadleaf forests- Albertine Rift montane forests
- Cameroonian Highlands forests
- East African montane forests
- Eastern Arc forests
- Ethiopian montane forests
- Guinean montane forests
- Knysna-Amatole montane forests
- Southern Afrotemperate Forest
- Mount Cameroon and Bioko montane forests
- Angolan montane forest-grassland mosaic
- Angolan scarp savanna and woodlands
- Drakensberg alti-montane grasslands and woodlands
- Drakensberg montane grasslands, woodlands and forests
- East African montane moorlands
- Eastern Zimbabwe montane forest-grassland mosaic
- Ethiopian montane grasslands and woodlands
- Ethiopian montane moorlands
- Highveld grasslands
- Jos Plateau forest-grassland mosaic
- Maputaland-Pondoland bushland and thickets
- Southern Afrotemperate Forest
- Rwenzori-Virunga montane moorlands
- South Malawi montane forest-grassland mosaic
- Southern Rift montane forest-grassland mosaic