Tropical zones in Africa and its surrounding areas
Although tropical Africa is mostly familiar to the West for its rainforests, this biogeographic realm of Africa is far more diverse. While the tropics are thought of as regions with hot moist climates, which are caused by latitude and the tropical rain belt, the geology of areas, particularly mountain chains, and geographical relation to continental and regional scale winds impact the overall areas [citation needed], also, making the tropics run from arid to humid in West Africa. The area is currently experiencing the negative effects of rapid human population growth.[1]
Tropical rainforests are moist forests of semi-deciduous plants distributed across nine West African countries. Institute for Sea Research conducted a temperature record dating back 700,000 years.[2] Several conservation and development demographic settings are such that the most loss of rain forests has occurred in countries with higher population growth. Lack of dependable data and survey information in some countries has made the account of areas of unbroken forest and/or under land use change and their relation to economic indicators difficult to ascertain. Hence, the amount and rate of deforestation in Africa are less known than other regions of tropics.
The term deforestation refers to the complete obstruction of forest canopy cover for means of agriculture, plantations, cattle-ranching, and other non-forest fields. Other forest use changes for example are forest disintegration (changing the spatial continuity and creating a mosaic of forest blocks and other land cover types), and dreadful conditions (selective logging of woody species for profitable purposes that affects the forest subfloor and the biodiversity).[2] The general meaning to the term deforestation is linked not only to the value system but the type of measurement designed to assess it. Thus, the same interpretations of deforestation cause noticeable changes in the estimate of forests cleared.
One reason for forest depletion is to grow cash crops. Nine West African countries depend on cash crop exports. Products like gum, copal, rubber, cola nuts, and palm oil provide rather steady income revenue for the West African countries. Land use change spoils entire habitats with the forests. Converting 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, that increased greatly between 1950 and 1980. Simultaneously, preservation measures were reinforced to protect European and American forests.[2] Economic growth and growing environmental protection in industrialized European countries made request for tropical hardwood to become strong in West Africa. In the first half of the 1980s, an annual forest loss of 7,200km2 (2,800sqmi) was note down along the Gulf of Guinea, a figure equivalent to 4-5 per cent of the total remaining rain forest area.[2] 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.[2]
Tropical timber became a viable choice to European wood following World War II, as trade with East European countries stop 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 rain forest destruction is connected to the problem of fuel wood.[2] 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.[2] With the high demand, the consumption of wood for fuel exceeds the renewal of forest cover.
The rain forests which remain in West Africa now merely are how they were hardly 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 the rain forest are cut down. Guinea-Bissau loses 200 to 350km2 (77 to 135sqmi) of forest yearly, Senegal 500km2 (190sqmi) of wooded savanna, and Nigeria 6,000,050,000 of both. Liberia exploits 800km2 (310sqmi) of forests each year. Extrapolating from present rates of loss, botanist Peter Raven pictures that the majority of the world's moderate and smaller rain forests (such as in Africa) could be ruined in forty years. Tropical Africa is about 18% of the world total covering 20millionkm2 (7.7millionsqmi) of land in West and Central Africa.[2] 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 150km2 (58sqmi) in Gabon to 2,900km2 (1,100sqmi) in Cote d'Ivoire. Remaining tropical forest still cover major areas in Central Africa but are abridged by patches in West Africa.
The African Timber Organization member countries (ATO) 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 of making the law. By comparison with rain forests in other places of the world in 1973, Africa showed the greatest infringement though in total volume means, African timber production accounted just one third compared to that of Asia.[2] 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, but they were not strict enough to fill forest exploitation. It wasn't until the 1970s that the inadequate performance of forest regulations was recognized. 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 (UNDP) and the World Bank with hopes of halting tropical forest destruction.[2] In its bid to stress forest conservation and development, the World Bank provided $111,103 million in building countries, especially in Africa, to help in developing long range forest conservation and management programs meant for ending deforestation.
Region protection
Many African countries are in economic and political change, overwhelmed by conflict, making various movements of forest exploitation to maintained forest management and production more and more complicated.
Forest legislation of ATO member countries aim to promote the balanced utilization of the forest domain and of wildlife and fishery in order to increase the input of the forest sector to the economic, social, cultural and scientific development of the country.[2]
Habitats
The tropical environment is rich in terms of biodiversity. Tropical African forest is 18 percent of the world total and covers over 3.6 million square kilometers of land in West, East and Central Africa. This total area can be subdivided to 2.69 million square kilometers (74%) in Central Africa, 680,000 square kilometers (19%) in West Africa, and 250,000 square kilometers (7%) in East Africa.[2] In West Africa, a chain of rain forests up to 350km long extends from the eastern border of Sierra Leone all the way to Ghana. In Ghana the forest zone gradually dispels near the Volta river, following a 300km stretch of Dahomey savanna gap. The rain forest of West Africa continues from east of Benin through southern Nigeria and officially ends at the border of Cameroon along the Sanaga river.
Semi-deciduous rainforests in West Africa began at the fringed coastline of Guinea Bissau (via Guinea) and run all the way through the coasts of Sierra Leone, Liberia, Ivory Coast, Ghana, continuing through Togo, Benin, Nigeria and Cameroon, and ending at the Congo Basin. Rain forests 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 greenhouse gases into the atmosphere, and lessen the planet's ability to store excess carbon.
The rain forest vegetation of the Guinea-Congolian transition area, extending from Senegal to western Uganda are constituted of two main types: The semi-deciduous rain forest characterized by a large number of trees whose leaves are left during dry season. It appears in areas where the dry period (rainfall below about 100mm) reach three months. Then, the evergreen or the semi-evergreen rain forest, 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 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.
Judging against rain forest areas in other continents, most of the African rainforest is rather dry and receives between 1600 and 2000mm 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 other rain forest regions in the world. The average monthly rainfall in nearly the whole region remains under 100mm throughout the year. The variety of the African rain forest flora is also less than the other rain forests. 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 18000 years ago.[2]
A recent vegetation map of Africa published by UNESCO and the main vegetation features of Central African rain forest divides the area into the following categories: . This type of forest shows no substantial seasonal behavior. At the border of the central basin is the mesophilous semi-deciduous forest that is mixed with deciduous and evergreen trees in the upper-stratum, unusual age distribution, continuous shrub stratum at the lower canopy, and a more marked seasonality.
Secondary forests
Beyond the forest reserves, a great deal of the remaining part of Central African rain forest on well drained soils are old secondary forests. There also exist younger secondary forests dominated by parasol trees, Musanga cecropioides, the most abundant and characteristic secondary forest in Africa. Such trees are found in upper layers of secondary growth along the old road networks in Zaïre . The dispersal of secondary forests are important in regional study as they show different floristic and faunistic characteristics than primary forests, and represent centers of human activity and history of land-use changes.
Non-forest
The nart comprises degraded lands, irregular agriculture and plantations., and deforested lands and fragmented forests. Plantations have a geometrical lay-out with uniform canopy-cover and follow a different vegetation cycle as their adjacent features. The areas are located near the transportation networks and are subjugated by economic tree crops such as cacao, rubber, oil palms and Kola.
Swamp and flooded forests
Swamp forest, inundated forests in flood plains, and riparian forests are found here. Swamp forests are found widely in the Zaïre basin and throughout the Congo basin where conditions are appropriate. In most areas, swamp forests is like in appearance to rain forest and the tallest trees attain a height of 45 m. The main canopy is often irregular and open, sometimes resembling the secondary forests caused by disturbance The forest has a variety in endemic flora but it is inadequate in species. Recently, large areas of swamp forests have been cleared for rice farming. Swamp forests in Zaïre, Congo and other lowland forests have seasonal variations that to the level of forest inundation.
Conservation
In colonial rule, governments planned only one way to promote conservation. In Nigeria for example, the government introduced forest protection regulatory measures by classification of some forest areas, licensing requirements, and the apprehension and prosecution of offenders. Ghana issued classification permits to firms and executed log export restrictions. The Ivory Coast and Cameroon introduced log supply quotas, as Liberia did.
This trade product is "raw" lumber. Trees native to the West African rainforest from which timber is exported include limba, emeri, obeche and opepe as well as the exotic species gmelina, teak, and pinus.
The Tropical African rainforest has rich fauna, commonly smaller mammal species rarely seen by humans. New species continually are being found. For instance, in late 1988 an unknown shrub species was discovered on the shores of the Median River in Western Cameroon. Since then many species have become extinct. However, undisturbed rainforests are some of the richest habitats of animal species. Today, undisturbed rainforests are remnant, but rare. Timber extraction not only changes the edifice of the forest, it affects the tree species spectrum by removing economically important species and terminates other species in the process. The species that compose African rainforests are of different evolutionary ages because of the contraction and expansion of the rainforest in response to global climatic fluctuations.[2] 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 allow 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. Unfortunately, many of these rare and unique species are endangered or critically endangered and need protection from poachers and provided ample habitat to thrive.
Flora
In Tropical Africa, about 8,500 plant species have been documented, including 403 orchid species.[citation needed]
Species unfamiliar to the changes in forest structure for industrial use might not survive.[2] 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 rain forests provide possible economic resource for over-populated developing countries. Despite the stated need to save the West African forests, there are divergence in how to work. In April 1992, countries with some of the largest surviving tropical rain forests banned a rainforest protection plan proposed by the British government. It aimed at finding endangered species of tropical trees in order to control trade in them. Experts estimate that the rainforest of West Africa, at the present trend of deforestation, may disappear by the year 2020.[2]
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.[2]
Recent news: History of Tropical Africa
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In early 2007, scientists created an entirely new proxy to determine annual mean air temperature on land—based on molecules from the cell membrane of soil inhabiting bacteria. Recently, Scientists from the NIOZ, Royal Netherlands Institute for Sea Research conducted a temperature record dating back to 25,000 years ago.[3] In concord with the German colleague of 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 was 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 in natural disparities in climate and the possible costs of a warming earth on precipitation in central Africa.[3]
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 shows 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 arrived 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.[3]
Ivory Coast is a sub-Saharan nation in southern West Africa located at 8 00°N, 5 00°W. The country is approximately square in shape. Its southern border is a 515 km (320 mi) coastline on the Gulf of Guinea on the north Atlantic Ocean. On the other three sides it borders five other African nations for a total of 3,458 km (2,149 mi): Liberia to the southwest for 778 km (483 mi), Guinea to the northwest for 816 km (507 mi), Mali to the north-northwest for 599 km (372 mi), Burkina Faso to the north-northeast for 545 km (339 mi), and Ghana to the east for 720 km (447 mi).
The Democratic Republic of the Congo (DRC) is the largest country of sub-Saharan Africa, occupying some 2,344,858 square kilometres (905,355 sq mi). Most of the country lies within the vast hollow of the Congo River basin. The vast, low-lying central area is a plateau-shaped basin sloping toward the west, covered by tropical rainforest and criss-crossed by rivers. The forest center is surrounded by mountainous terraces in the west, plateaus merging into savannas in the south and southwest. Dense grasslands extend beyond the Congo River in the north. High mountains of the Ruwenzori Range are found on the eastern borders with Rwanda and Uganda.
Deforestation or forest clearance is the removal of a forest or stand of trees from land that is then converted to non-forest use. Deforestation can involve conversion of forest land to farms, ranches, or urban use. The most concentrated deforestation occurs in tropical rainforests. About 31% of Earth's land surface is covered by forests at present. This is one-third less than the forest cover before the expansion of agriculture, a half of that loss occurring in the last century. Between 15 million to 18 million hectares of forest, an area the size of Bangladesh, are destroyed every year. On average 2,400 trees are cut down each minute.
A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' Food and Agriculture Organization (FAO) defines a forest as, "Land spanning more than 0.5 hectares with trees higher than 5 meters and a canopy cover of more than 10 percent, or trees able to reach these thresholds in situ. It does not include land that is predominantly under agricultural or urban use." Using this definition, Global Forest Resources Assessment 2020 found that forests covered 4.06 billion hectares, or approximately 31 percent of the world's land area in 2020.
Ghana is a West African country in Africa, along the Gulf of Guinea.
Rainforests are characterized by a closed and continuous tree canopy, moisture-dependent vegetation, the presence of epiphytes and lianas and the absence of wildfire. Rainforest can be classified as tropical rainforest or temperate rainforest, but other types have been described.
Tropical and subtropical moist broadleaf forests (TSMF), also known as tropical moist forest, is a subtropical and tropical forest habitat type defined by the World Wide Fund for Nature.
Tropical rainforests are rainforests that occur in areas of tropical rainforest climate in which there is no dry season – all months have an average precipitation of at least 60 mm – and may also be referred to as lowland equatorial evergreen rainforest. True rainforests are typically found between 10 degrees north and south of the equator ; they are a sub-set of the tropical forest biome that occurs roughly within the 28-degree latitudes. Within the World Wildlife Fund's biome classification, tropical rainforests are a type of tropical moist broadleaf forest that also includes the more extensive seasonal tropical forests.
Taï National Park is a national park in Côte d'Ivoire that contains one of the last areas of primary rainforest in West Africa. It was inscribed as a World Heritage Site in 1982 due to the diversity of its flora and fauna. Five mammal species of the Taï National Park are on the Red List of Threatened Species: pygmy hippopotamus, olive colobus monkeys, leopards, chimpanzees and Jentink's duiker.
In West Africa, the forest zone refers to the southern part of the region once covered by tropical rainforest. Sometimes this region is referred to as Guinea to distinguish it from the grassland-covered Sudan, drier Sahel and per-arid Sahara. it's is made-up of vegetation having mainly trees and consist of the following local biotic communities: -mangrove swamp forest -tropical rain forest.
The wildlife of Ivory Coast consists of the flora and fauna of this nation in West Africa. The country has a long Atlantic coastline on the Gulf of Guinea and a range of habitat types. Once covered in tropical rainforest, much of this habitat has been cleared, the remaining terrain being gallery forests and savanna with scattered groups of trees, resulting in a decrease in biodiversity. As of 2016, 252 species of mammal had been recorded in Ivory Coast, 666 species of bird, 153 species of reptile, 80 species of amphibian, 671 species of fish and 3660 species of vascular plant.
The wildlife of Liberia consists of the flora and fauna of the Republic of Liberia. This West African nation has a long Atlantic coastline and a range of habitat types, with a corresponding diversity of plants and animals. Liberia is considered a biodiversity hotspot and has more intact forests characteristic of the Upper Guinea Massif than do neighbouring countries. There are 2000 species of vascular plants, approximately 140 species of mammals, and over 600 species of birds.
Sapo National Park is a national park in Sinoe County, Liberia. It is the country's largest protected area of rainforest, was the first national park established in the country, and contains the second-largest area of primary tropical rainforest in West Africa after Taï National Park in neighbouring Côte d'Ivoire. Agriculture, construction, fishing, hunting, human settlement, and logging are prohibited in the park.
Eremospatha is a genus of climbing flowering plants in the palm family found in tropical Africa. These rattans are uncommon in cultivation and poorly understood by taxonomists;. Closely related to Laccosperma, they differentiated by the near complete absence of bracts and bracteoles. The name is from Greek meaning "without a spathe".
Ndian is a department of Southwest Region in Cameroon. It is located in the humid tropical rainforest zone about 650 km (400 mi) southeast of Yaoundé, the capital.
Tropical vegetation is any vegetation in tropical latitudes. Plant life that occurs in climates that are warm year-round is in general more biologically diverse that in other latitudes. Some tropical areas may receive abundant rain the whole year round, but others have long dry seasons which last several months and may vary in length and intensity with geographic location. These seasonal droughts have great impact on the vegetation, such as in the Madagascar spiny forests. Rainforest vegetation is categorized by five layers. The top layer being the upper tree layer. Here you will find the largest and widest trees in all the forest. These trees tend to have very large canopy's so they can be fully exposed to sunlight. A layer below that is the middle tree layer. Here you will find more compact trees and vegetation. These trees tend to be more skinny as they are trying to gain any sunlight they can. The third layer is the lower tree area. These trees tend to be around five to ten meters high and tightly compacted. The trees found in the third layer are young trees trying to grow into the larger canopy trees. The fourth layer is the shrub layer beneath the tree canopy. This layer is mainly populated by sapling trees, shrubs, and seedlings. The fifth and final layer is the herb layer which is the forest floor. The forest floor is mainly bare except for various plants, mosses, and ferns. The forest floor is much more dense than above because of little sunlight and air movement.
Seasonal tropical forest, also known as moist deciduous, semi-evergreen seasonal, tropical mixed or monsoon forests, typically contain a range of tree species: only some of which drop some or all of their leaves during the dry season. This tropical forest is classified under the Walter system as (i) tropical climate with high overall rainfall and (ii) having a very distinct wet season with dry season. These forests represent a range of habitats influenced by monsoon (Am) or tropical wet savannah (Aw) climates. Drier forests in the Aw climate zone are typically deciduous and placed in the Tropical dry forest biome: with further transitional zones (ecotones) of savannah woodland then tropical and subtropical grasslands, savannas, and shrublands.
The Guineo-Congolian region is a biogeographical region in Africa straddling the Equator and stretching from the Atlantic Ocean through the Congo Basin to the Congo / Nile divide in Rwanda and Burundi. Formerly, this region was largely covered in rain forest, on both well-drained sites and in swamp forests, but little undisturbed primary forest now remains, having been replaced in many areas by savanna and secondary-growth forest.
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.
Polyscias fulva is a species of flowering plant. It is an evergreen or deciduous tree, native to the mountains of tropical Africa and the southwestern Arabian Peninsula.
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