The Afrotropical realm is one of the Earth's eight biogeographic realms. It includes Sub-Saharan Africa, the southern Arabian Peninsula, the island of Madagascar, and the islands of the western Indian Ocean. It was formerly known as the Ethiopian Zone or Ethiopian Region.
A belt of tropical moist broadleaf forest also runs along the Indian Ocean coast, from southern Somalia to South Africa.
The Afrotropic has various endemic bird families, including (Struthionidae), the secretary bird (Sagittariidae), guineafowl (Numididae), and (Coliidae). Several families of passerines are limited to the Afrotropics, including (Chaetopidae) and rockfowl (Picathartidae).
Africa has three endemic orders of mammals, the Tubulidentata (), Afrosoricida ( and ), and Macroscelidea (). The East-African plains are well known for their diversity of large mammals.
Four species of great apes (Hominidae) are endemic to Central Africa: both species of gorilla (western gorilla, Gorilla gorilla, and eastern gorilla, Gorilla beringei) and both species of chimpanzee (common chimpanzee, Pan troglodytes, and bonobo, Pan paniscus). and their ancestors originated in Africa.
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Semi-deciduous rainforests in West Africa begin at the fringed coastline of Guinea-Bissau (via Guinea) and run through the coasts of Sierra Leone, Liberia, Ivory Coast, Ghana, continuing through Togo, Benin, Nigeria and Cameroon, and ending at the Congo Basin. Rainforests such as these are the richest, oldest, most prolific, and most complex systems on Earth, are dying, and in turn, are upsetting the delicate ecological balance. This may disturb global hydrological cycles, release vast amounts of into the atmosphere, and lessen the planet's ability to store excess carbon.
The rainforest vegetation of the Guinea-Congolian transition area, extending from Senegal to western Uganda is constituted of two main types: The semi-deciduous rainforest is characterized by a large number of trees whose leaves are left during the dry season. It appears in areas where the dry period (rainfall below about 100 mm) reaches three months. Then, the evergreen or the semi-evergreen rainforest climatically adapted to somewhat more humid conditions than the semi-deciduous type and is usually there in areas where the dry period is shorter than two months. This forest is usually richer in legumes and a variety of species and its maximum development is around the Bight of Biafra, from Eastern Nigeria to Gabon, and with some large patches leaning to the west from Ghana to Liberia and to the east of Zaïre-Congo basin.
Among rainforest areas in other continents, most of the African rainforest is comparatively dry and receives between 1600 and 2000 mm of rainfall per year. Areas receiving more rain than this mainly are in coastal areas. The circulation of rainfall throughout the year remains less than in other rainforest regions in the world. The average monthly rainfall in nearly the whole region remains under 100 mm throughout the year. The variety of the African rainforest flora is also less than the other rainforests. This lack of flora has been credited to several reasons such as the gradual infertility since the Miocene, severe dry periods during Quaternary, or the refuge theory of the cool and dry climate of tropical Africa during the last severe ice age of about 18,000 years ago.
The pygmy hippopotamus, the giant forest hog, the water chevrotain, insectivores, rodents, bats, tree frogs, and bird species inhabit the forest. These species, along with a diversity of fruits and insects, make a special habitat that allows for a diversity of life. The top canopy is home to monkey species like the red colobus, Black-and-white Colobus, and many other Old-World monkey species. Many of these rare and unique species are endangered or critically endangered and need protection from poachers and provided ample habitat to thrive.
Species unfamiliar with the changes in forest structure for industrial use might not survive. If timber use continues and an increasing amount of farming occurs, it could lead to the mass killing of animal species. The home of nearly half of the world's animals and plant species are tropical rainforests. The rainforests provide economic resources for over-populated developing countries. Despite the stated need to save the West African forests, there are varied opinions on how best to accomplish this goal. In April 1992, countries with some of the largest surviving tropical rainforests banned a rainforest protection plan proposed by the British government. It aimed at finding endangered species of tropical trees to control their trade. Experts estimate that the rainforest of West Africa, at the present rate of deforestation, may disappear by the year 2020.
Africa's rainforest, like many others emergent in the world, has a special significance to the indigenous peoples of Africa who have occupied them for millennia.
Forest legislation of ATO member countries aims to promote the balanced utilization of the forest domain and of wildlife and fishery to increase the input of the forest sector to the economic, social, cultural, and scientific development of the country.
The cultivation of various has led to forest depletion. West African countries depend on products like gum, copal, rubber, cola nuts, and palm oil as a source of steady income. Land use change spoils entire habitats with the forests. The conversion of forests into timber is another cause of deforestation. Over decades, the primary forest product was commercial timber. Urbanized countries account for a great percentage of the world's wood consumption, which increased greatly between 1950 and 1980. Simultaneously, preservation measures were reinforced to protect European and American forests. Economic growth and growing environmental protection in industrialized European countries caused increased demand for tropical hardwood from West Africa. In the first half of the 1980s, an annual forest loss of was noted down along the Gulf of Guinea, a figure equivalent to 4-5 percent of the total remaining rainforest area. By 1985, 72% of West Africa's rainforests had been transformed into fallow lands and an additional 9% had been opened up by timber exploitation.
Tropical timber was used in Europe following World War II, as trade with East European countries stopped and timber noticeably became sparse in western and southern Europe. Despite efforts to promote lesser-known timber species use, the market continued to focus on part of the usable timber obtainable. West Africa was prone to selective harvesting practices; while conservationists blamed the timber industry and the farmers for felling trees, others believe rainforest destruction is connected to the problem of fuel wood. The contribution of fuel wood consumption to tree stock decline in Africa is believed to be significant. It is generally believed that firewood provides 75% of the energy used in sub-Sahara Africa. With the high demand, the consumption of wood for fuel exceeds the renewal of forest cover.
Other observed changes in these forests are forest disintegration (changing the spatial continuity and creating a mosaic of forest blocks and other land cover types), and selective logging of woody species for profitable purposes that affect the forest subfloor and the biodiversity.
The rainforests that remain in West Africa now greatly differ in condition from their state 30 years ago. In Guinea, Liberia, and the Ivory Coast, there is almost no primary forest cover left unscathed; in Ghana, the situation is much worse, and nearly all of the rainforest is being removed. Guinea-Bissau loses of forest yearly, Senegal of wooded savanna, and Nigeria 6,000,050,000 of both. Liberia loses of forests each year. Extrapolating from present rates of loss, botanist Peter Raven pictures that the majority of the world's moderate and smaller rainforests (such as in Africa) could be destroyed in forty years. Tropical Africa comprises 18% of the world's total land area covering of land in West and Central Africa. The region has been facing deforestation in various degrees of intensity throughout the recent decades. The actual rate of deforestation varies from one country to another and accurate data does not exist yet. Recent estimates show that the annual pace of deforestation in the region can vary from in Gabon to in Côte d'Ivoire. The remaining tropical forests still cover major areas in Central Africa but are abridged by patches in West Africa.
The African Timber Organization member countries eventually recognized the cooperation between rural people and their forest environment. Customary law gives residents the right to use trees for firewood, fell trees for construction, and collect of forest products and rights for hunting or fishing and grazing or clearing of forests for maintenance agriculture. Other areas are called "protected forests", which means that uncontrolled clearings and unauthorized logging are forbidden. After World War II, commercial exploitation increased until no West African forestry department was able to make the law. By comparison with rainforests in other places of the world in 1973, Africa showed the greatest infringement though in total volume means, African timber production accounted for just one-third compared to that of Asia. The difference was due to the variety of trees in Africa forests and the demand for specific wood types in Europe.
Forestry regulations in East Africa were first applied by colonial governments. The Tropical Forestry Action Plan was conceived in 1987 by the World Resources Institute in cooperation with the Food and Agriculture Organization, the United Nations Development Program, and the World Bank with hopes of halting tropical forest destruction. In its bid to stress forest conservation and development, the World Bank provided $111,103 million to developing countries, especially in Africa, to help in developing long-range forest conservation and management programs meant for ending deforestation.
In concordance with their German colleagues at the University of Bremen, this detailed record shows the history of land temperatures based on the molecular fossils of soil bacteria. When applying this to the outflow core of the Congo River, the core contained eroded land material and microfossils from marine algae. That concluded that the land environment of tropical Africa cooled more than the bordering Atlantic Ocean during the last ice age. Since the Congo River drains a large part of tropical central Africa, the land-derived material gives an integrated signal for a very large area. These findings further enlighten natural disparities in climate and the possible costs of a warming earth on precipitation in central Africa.
Scientists discovered a way to measure sea temperature—based on organic molecules from algae growing off the surface layer of the Ocean. These organisms acclimatize the molecular composition of their cell membranes to ambient temperature to sustain regular physiological properties. If such molecules sink to the sea floor and are buried in sediments where oxygen does not go through, they can be preserved for thousands of years. The ratios between the different molecules from the algal cell membrane can approximate the past temperature of the sea surface. The new “proxy” used in this sediment core obtained both a continental and a sea surface temperature record. In comparison, both records show that ocean surface and land temperatures behaved differently during the past 25,000 years. During the last ice age, African temperatures were 21 °C, about 4 °C lower than today, while the tropical Atlantic Ocean was only about 2.5 °C cooler. Lead author Johan Weijers and his colleagues concluded that the land-sea temperature difference has by far the largest influence on continental rainfall. The relation of air pressure to temperature strongly determines this factor. During the last ice age, the land climate in tropical Africa was drier than it is now, whereas it favors the growth of a lush rainforest.
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