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58-663: The rainforest in the Congo Basin is the largest rainforest in Africa and second only to the Amazon rainforest in size, with 300 million hectares compared to the 800 million hectares in the Amazon. Because of its size and diversity the basin's forest is important for mitigating climate change in its role as a carbon sink . However, deforestation and degradation of the ecology by the impacts of climate change may increase stress on

116-447: A global level, Congo's forests act as the planet's second lung, counterpart to the rapidly dwindling Amazon. They are a huge " carbon sink ", trapping carbon that could otherwise remain carbon dioxide. The Congo Basin holds roughly 8% of the world's forest-based carbon. If these woodlands are deforested, the carbon they trap will be released into the atmosphere. Predictions for future unabated deforestation estimate that by 2050 activities in

174-471: A mean size exceeding 500 km2 in some parts of the Congo Basin. Temperatures in the Congo Basin (usually between 20 and 30 °C) are lower than in the African desert regions to the north ( The Sahara ) and to the south ( Kalahari ). The differences in temperature between the deserts and the Congo Basin is important for driving wind systems known as African easterly jets , which affect climate and weather in

232-467: A new forestry code that requires companies to invest in local development and follow a sustainable, 25-year cycle of rotational logging. When a company is granted a concession from the central government to log in Congo, it must sign an agreement with the local chiefs and hereditary land owners, who give permission for it to extract the trees in return for development packages. In theory, the companies must pay

290-649: A number of active and dormant volcanoes, among them: Mount Kilimanjaro , Mount Kenya , Mount Longonot , Menengai Crater, Mount Karisimbi , Mount Nyiragongo , Mount Meru and Mount Elgon , as well as the Crater Highlands in Tanzania. Although most of these mountains lie outside of the rift valley, the EAR created them. Notable active examples of EAR volcanism include Erta Ale , Dalaffilla (also called Gabuli, Alu-Dalafilla), and Ol Doinyo Lengai . Erta Ale

348-795: Is a basaltic shield volcano in the Afar Region of northeastern Ethiopia, active continuously since at least 1967, with a summit lava lake documented since at least 1906. The 2008 eruption of Dalafilla, its only documented activity since the start of the Holocene , is the largest recorded eruption in Ethiopian history. Ol Doinyo Lengai is currently the only active natrocarbonatite volcano on Earth. Its magma contains almost no silica; typical lava flows have viscosities of less than 100 Pa⋅s, comparable to olive oil at 26 °C (79 °F). EAR-related volcanic structures with dated activity since

406-586: Is an active continental rift zone in East Africa . The EAR began developing around the onset of the Miocene , 22–25 million years ago. It was formerly considered to be part of a larger Great Rift Valley that extended north to Asia Minor . A narrow zone, the rift is a developing divergent tectonic plate boundary where the African plate is in the process of splitting into two tectonic plates, called

464-484: Is constructive to test hypotheses on computer based geodynamical models. A 3D numerical geodynamic model of the plume-crust coupling was capable of reproducing the lateral asymmetry of the EAR around the Tanzania craton . Numerical modeling of plume-induced continental break-up shows two distinct stages, crustal rifting followed by lithospheric breakup, and the upwelling between stages of an upper mantle plume. Prior to

522-653: Is depleting the rainforests of wildlife. With annual forest loss of 0.3% during the 2000s, the region had the lowest deforestation rate of any major tropical forest zone. From 2015 to 2019, the rate of deforestation in the Democratic Republic of the Congo doubled. In 2021, deforestation of the Congolese rainforest increased by 5%. Over the past 20 years, 17.1 million hectares of forest have been cut down. East African Rift The East African Rift ( EAR ) or East African Rift System ( EARS )

580-478: Is endemic to the northeastern Congolian rainforests. The rainforests have 1,000 native species of birds like the grey parrot , brown nightjar and the bat hawk , and 700 species of fish like the Nile tilapia , Nile perch and the giraffe catfish . Threats to the rainforests include destruction and fragmentation of forests by commercial logging, oil palm plantations, and mining. The bushmeat trade and poaching

638-635: Is home to the okapi , African forest elephant , pygmy hippopotamus , bongo (antelope) , chimpanzee , bonobo and the Congo peafowl . Its apex predator is the Leopard , which are larger than their savannah counterparts due to lack of competition from other large predators. The basin is home to the endangered western lowland gorilla . In 2010, the United Nations Environment Programme warned that gorillas could be extinct from

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696-413: Is relatively low to the north of the equator (<80 mm per month). In southern hemisphere winter, rainfall is instead lower to the south of the equator (<80 mm per month). The annual rhythm of the wind systems which carry water vapour account for the rainfall seasonality. Much of the rainfall is derived from large Mesoscale convective systems . The systems last over 11 hours on average and have

754-544: Is uncertain, it is likely that extreme rainfall events will become more extreme owing to the increases in water vapour in the atmosphere. Owing to the global climatic importance of the Congo Basin, it has been suggested that, along with the Amazon, severe changes in the rainfall or climate of the Congo Rainforest could act as a ' tipping point ', with widespread impacts on the Earth System. The Congo forest

812-643: The Chambeshi , the Uele and Ubangi rivers in the upper reaches and the Lualaba River draining wetlands in the middle reaches. Because of the young age and active uplift of the East African Rift at the headwaters , the river's yearly sediment load is very large, but the drainage basin occupies large areas of low relief throughout much of its area. It is delineated largely by swells including

870-620: The DRC will release roughly the same amount of carbon dioxide as the United Kingdom has emitted over the last 60 years. A 2013 study by British scientists showed that deforestation in the Congo Basin rainforest was slowing down. In 2017, British scientists discovered that peatlands in the Cuvette Centrale , which cover a total of 145,500 sq km, contain 30 billion tonnes of carbon, or 20 years of U.S. fossil fuel emissions. In 2021,

928-558: The Ethiopian Highlands and the Kenya Highlands are hotspots of higher rainfall amid the semi-arid to arid lowlands of East Africa. Lakes which form within the rift, including Lake Victoria , have a large effect on regional climate. They are a source of water vapour, and also lead to the formation of lake breeze systems , which affect weather across large areas of East Africa. The east to west river valleys within

986-654: The Main Ethiopian Rift , runs southward from the Afar triple junction, and continues south as the Kenyan Rift Valley, then transects Congo DR , Uganda , Rwanda , Burundi , Zambia , Tanzania , Malawi and Mozambique . The Western Rift Valley includes the Albertine Rift , and farther south, the valley of Lake Malawi . The rift also continues offshore from the coast of Mozambique along

1044-641: The Oligocene , with the majority of the volcanism coinciding with the opening of the Red Sea and the Gulf of Aden approximately 30 Ma. The composition of the volcanics are a continuum of ultra-alkaline to tholeiitic and felsic rocks. It has been suggested that the diversity of the compositions could be partially explained by different mantle source regions. The EAR also cuts through old sedimentary rocks deposited in ancient basins. The East African Rift Zone includes

1102-640: The Paleozoic , but the deformation over this period led to rapid erosion of much of this Paleozoic rock, creating a large unconformity . Sediment started to rapidly accumulate in the basin from the Mesozoic ( Triassic ) up to the present day. Deposits throughout the Jurassic suggest the presence of a freshwater, lacustrine habitat in the basin, and this continued into the Early Cretaceous . By

1160-541: The Sahel and Southern Africa . Future climate projections indicate that the region will get hotter in response to global climate change. There is more uncertainty over how average rainfall in the region will change, with the climate models used by the Intergovernmental Panel on Climate Change (IPCC) disagreeing on core elements of the rainfall distribution in the region. While the average rainfall change

1218-641: The Somali plate and the Nubian plate , at a rate of 6–7 mm (0.24–0.28 in) per year. The rift system consists of three microplates, the Victoria microplate to the north, and the Rovuma and Lwandle microplates to the south. The Victoria microplate is rotating anti-clockwise with respect to the African plate. Its rotation is caused by the configuration of mechanically weaker and stronger lithospheric regions in

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1276-531: The basin of the Congo River and its tributaries in Central Africa . The Congolian rainforest is the world's second-largest tropical forest , after the Amazon rainforest . It covers over 500,000,000 acres (2,000,000 km ) across six countries and contains a quarter of the world's remaining tropical forest. The Congolian forests cover southeastern Cameroon , Gabon , Republic of the Congo ,

1334-399: The lithosphere in saturated areas, making the thinning lithosphere behave like a mid-ocean ridge . According to marine geologist Kathleen Crane , the rift could eventually cause eastern Africa to separate from the mainland, although this potential event could take tens of millions of years. Studies that contribute to the broader understanding on the evolution of rifts can be grouped into

1392-622: The western lowland gorilla . There are also a number of other species of primates, including the chimpanzee , black colobus monkey , red colobus monkey , and olive baboon . To the north, south, and southwest, the forests transition to drier forest-savanna mosaic , a mosaic of drier forests, savannas , and grasslands . To the west, the Congolian forests transition to the coastal Lower Guinean forests , which extend from southwestern Cameroon into southern Nigeria and Benin ; these forest zones share many similarities and are sometimes known as

1450-443: The Amazon and Southeast Asian rainforests. However, its plant and animal life is still more rich and varied than most other places on Earth. The Congolian Forests are a global 200 ecoregion . There are over 400 species of mammals in the rainforest, including African forest elephants , African bush elephants , leopards , bongos , red river hogs , chimpanzees , bonobos , mountain gorillas , and lowland gorillas . The okapi

1508-534: The Bie, Mayumbe, Adamlia, Nil-Congo , East African, and Zambian Swells. The basin ends where the river empties into the Gulf of Guinea on the Atlantic Ocean. The basin is a total of 3.7 million square kilometers and is home to some of the largest undisturbed stands of tropical rainforest on the planet, in addition to large wetlands. Countries wholly or partially in the Congo region: The first inhabitants of

1566-466: The Congo Basin area were believed to be pygmies , and at that time, the dense forests and wet climate kept the population of the region low, with the prevention of hunter-gatherer society, whose remnants of their culture survive to the present day. Eventually Bantu peoples migrated there and founded the Kingdom of Kongo . Belgium , France , and Portugal later established colonial control over

1624-495: The Congo Basin. The Congo Basin is a globally important climatic region with annual rainfall of between 1500 and 2000 mm. It is one of three hotspots of deep convection ( thunderstorms ) in the tropics, the other two being over the Maritime continent and the Amazon . These three regions together drive the climate circulation of the tropics and beyond. The Congo Basin has the highest lightning strike frequency of anywhere on

1682-639: The Cretaceous, possibly due to a shock from a sudden decrease in the rate of seafloor spreading of the southern Mid-Atlantic Ridge , are the source of the region's famous diamonds . By the Cenozoic , an uplift in the borders of the Cuvette Centrale had blocked any further marine connections. During the Paleogene , high rainfall turned the basin into a series of marshy ponds and swamps. A shift to more arid conditions with seasonal droughts occurred with

1740-404: The EAR. The results corroborate the coexistence of a superplume "common to the entire rift" with another mantle material source being either of subcontinental type or of mid-ocean ridge type. The geophysical method of seismic tomography is a suitable tool to investigate Earth's subsurface structures deeper than the crust. It is an inverse problem technique that models which are the velocities of

1798-945: The EARS. Many of the African Great Lakes lie within the Rift Valley. A series of distinct rift basins, the East African Rift System extends over thousands of kilometers. North of the Afar triple junction, the rift follows two paths: west to the Red Sea Rift and east to the Aden Ridge in the Gulf of Aden . Southward from the Afar triple junction , the EAR consists of two main branches. The Eastern Rift Valley (also known as Gregory Rift ) includes

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1856-602: The Kerimba and Lacerda grabens , which are joined by the Davie Ridge, a 2,200 km-long (1,400 mi) relic fracture zone that cuts across the West Somali basin, straddling the boundary between Tanzania and Mozambique. The Davie Ridge ranges between 30–120 km (19–75 mi) wide, with a west-facing scarp (east-plunging arch) along the southern half of its length that rises to 2,300 m (7,500 ft) above

1914-562: The Lower Guinean-Congolian forests. To the east, the lowland Congolian forests transition to the highland Albertine Rift montane forests , which cover the mountains lining the Albertine Rift , a branch of the East African Rift system. The World Wide Fund for Nature divides the Congolian forests into six distinct ecoregions : The Congolian rainforests are home to over 10,000 species of plants of which 30% are endemic . The Congolian rainforests are less biodiverse than

1972-614: The Somali Jet) in the western Indian Ocean . The Somali Jet supplies water vapour for the high rainfall during the Indian Monsoon and is responsible for roughly half the global cross-equatorial atmospheric mass flux in the lower-branch of Hadley Circulation . The Rift Valley in East Africa has been a rich source of hominid fossils that allow the study of human evolution. The rapidly eroding highlands quickly filled

2030-532: The case, there could be a financial incentive for protecting forests. L’Île Mbiye, an island in the Lualaba River in Kisangani , is part of a project about forest ecosystem conservation, conducted by Stellenbosch University . Democratic Republic of the Congo is also looking to expand the area of forest under protection, for which it hopes to secure compensation through emerging markets for forest carbon. The main Congolese environmental organization working to save

2088-474: The deforestation rate of the Congolese rainforest increased by 5%. The Global Forest Atlas estimated that the logging industry covers from 44 to 66 million hectares of forest. A study published in 2019 in Nature Sustainability showed that 54,000 miles of roads for forest concessions were built between 2003 and 2018, reaching a total of 143,500 miles. A moratorium on logging in the Congo forest

2146-614: The development of deep asymmetric basins. The second stage of rifting was characterized by the deactivation of large boundary faults, the development of internal fault segments, and the concentration of magmatic activity towards the rifts. Today, the narrow rift segments of the East African Rift system form zones of localized strain. These rifts are the result of the actions of numerous normal faults which are typical of all tectonic rift zones. As aforementioned, voluminous magmatism and continental flood basalts characterize some of

2204-563: The effects of deep-rooted mantle plumes are an important hypothesis, their location and dynamics are poorly understood, and a matter of active research. The question is still debated. The most recent and accepted view is the theory put forth in 2009: that magmatism and plate tectonics have a feedback with one another, controlled by oblique rifting conditions. According to this theory, lithospheric thinning generates volcanic activity, further increasing magmatic processes such as intrusions and numerous small plumes. These processes further thin

2262-582: The entire region by the late 19th century. The General Act of the Berlin Conference of 1885 gave a precise definition to the "conventional basin" of the Congo, which included the entire actual basin plus some other areas. The General Act bound its signatories to neutrality within the conventional basin, but this was not respected during the First World War . The World Resources Institute estimated that 80 million people live in and around

2320-623: The forest ecosystem, in turn making the hydrology of the basin more variable. A 2012 study found that the variability in precipitation caused by climate change will negatively affect economic activity in the basin. Eight sites of the Congo Basin are inscribed on the World Heritage List , five being also on the list of World Heritage in Danger (all five located in Democratic Republic of the Congo ). Fourteen percent of

2378-452: The forests is an NGO called OCEAN, which serves as the link between international outfits like Greenpeace and local community groups in the concessions. 0°00′00″N 22°00′00″E  /  0.0000°N 22.0000°E  / 0.0000; 22.0000 Congolian rainforests The Congolian rainforests ( French : Forêts tropicales congolaises ) are a broad belt of lowland tropical moist broadleaf forests which extend across

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2436-551: The government nearly $ 18 million rent per year for these concessions, of which 40% should be returned to provincial governments for investment in social development of the local population in the logged areas. In its current form, the Kyoto Protocol does not reward so-called "avoided deforestation"—initiatives that protect forest from being cut down. But many climate scientists and policymakers hope that negotiations for Kyoto's successor will include such measures. If this were

2494-410: The greater Congo Basin in a matter of 15 years. The Congo Basin is the largest forest in Africa. More than 10,000 plant species can be found in and around the forest. The humid forests cover 1.6 million km². The Congo Basin is an important source of African teak , used for building furniture and flooring. An estimated 40 million people depend on these woodlands, surviving on traditional livelihoods. At

2552-546: The humid forest is designated as protected. The Congo Basin is a large depression within the Congo Craton , making it a patch of relatively recent ( Phanerozoic -aged, and mostly Mesozoic & onwards) sedimentary rock within a large, otherwise extremely ancient ( Archean -aged) piece of exposed continental crust. The deformation of the Craton began as early as the late Cambrian or early Ordovician and continued over

2610-405: The inner Earth that reproduce the seismographic data recorded all around the world. Recent improvements of tomographic Earth models of P wave and S wave velocities suggest that a superplume upwelling from the lower mantle at the northeastern EAR feeds plumes of smaller scale into the upper mantle . Parallel to geological and geophysical measures (e.g. isotope ratios and seismic velocities) it

2668-415: The northern and central Democratic Republic of the Congo , and portions of southern and central Africa. The Congolian rainforest is home to a large number of flora and fauna, including more than 10,000 species of plants and over 10,000 species of animals. It is estimated that the region contains more than a quarter of the world’s plant species and is home to one of the world’s most threatened primate species,

2726-671: The onset of the Holocene include approximately 50 in Ethiopia, 17 in Kenya , and 9 in Tanzania . The EAR is the largest seismically active rift system on Earth today. The majority of earthquakes occur near the Afar Depression, with the largest typically occurring along or near major border faults. Seismic events in the past century are estimated to have reached a maximum moment magnitude of 7.0. The seismicity trends parallel to

2784-546: The planet. The high rainfall supports the second largest rainforest on Earth, which is a globally significant carbon sink and an important component of the global carbon cycle . Averaged across the whole basin, there are two major rainfall seasons in March to May and September to November. In both hemispheres the rainfall maximises in September to November, at above 210 mm per month. In northern hemisphere winter, rainfall

2842-729: The rift segments, while other segments, such as the Western branch, have only very small volumes of volcanic rock. The African continental crust is generally cool and strong. Many cratons are found throughout the EAR, such as the Tanzania and Kaapvaal cratons . The cratons are thick, and have survived for billions of years with little tectonic activity. They are characterized by greenstone belts , tonalites , and other high-grade metamorphic lithologies. The cratons are of significant importance in terms of mineral resources , with major deposits of gold, antimony, iron, chromium and nickel. A large volume of continental flood basalts erupted during

2900-691: The rift system, including the Turkana Channel in northern Kenya and the Zambezi river valley, concentrate low-level easterly winds and accelerate them towards Central Africa . This leaves East Africa drier than it otherwise would be, and also supports the high rainfall in the Congo Basin rainforest . The formation of the east–west valleys could in turn be important for the aridification of East Africa over millions of years. The barrier presented by EARS concentrates monsoonal winds (known as

2958-451: The rift system, with a shallow focal depth of 12–15 km (7.5–9.3 mi) beneath the rift axis. Further away from the rift axis, focal depths can be below 30 km (19 mi). Focal mechanism solutions strike NE and frequently demonstrate normal dip-slip faulting, although left-lateral motion is also observed. The East African Rift system affects regional, continental and even global climate. Regions of higher elevation, including

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3016-520: The rift's formation, enormous continental flood basalts erupted, uplifting the Ethiopian , Somali, and East African plateaus. The first stage of rifting of the EAR was characterized by rift localization and magmatism along the entire rift zone. Periods of extension alternated with relative inactivity. There was also the reactivation of a pre-Cambrian weakness in the crust, a suture zone of multiple cratons , displacement along large boundary faults, and

3074-432: The sea floor. Its movement is concurrent with the EAR. Over time, many theories have tried to clarify the evolution of the East African Rift. In 1972 it was proposed that the EAR was not caused by tectonic activity, but rather by differences in crustal density. Since the 1990s, evidence has been found in favor of mantle plumes beneath the EAR. Others proposed an African superplume causing mantle deformation. Although

3132-699: The start of the Late Cretaceous , a connection with the Trans-Saharan seaway led to a significant marine incursion into the basin (evidence of an earlier, Late Jurassic marine intrusion is disputed), causing it to serve as a connection between the southern Atlantic Ocean and the Tethys Ocean . Many of the formations deposited by these freshwater and marine habitats are rich in pollen, invertebrate, and vertebrate (primarily fish) fossils . Kimberlite pipes that are thought to have formed during

3190-436: The start of the Neogene . Later in the Neogene, a sudden shift to fluvial deposits suggests a dramatic return to wetter conditions. The following sedimentary geological formations have been deposited in the basin: Congo is a traditional name for the equatorial Middle Africa that lies between the Gulf of Guinea and the African Great Lakes . The basin begins in the highlands of the East African Rift system with input from

3248-410: The techniques of isotope geochemistry, seismic tomography and geodynamical modeling. The varying geochemical signatures of a suite of Ethiopian lavas suggest multiple plume sources: at least one of deep mantle origin, and one from within the subcontinental lithosphere. In accordance, a 2014 study compares the geochemical signature of rare earth isotopes from xenoliths and lava samples collected in

3306-455: The valley with sediments, creating a favorable environment for the preservation of remains. The bones of several hominid ancestors of modern humans have been found here, including those of " Lucy ", a partial australopithecine skeleton discovered by anthropologist Donald Johanson dating back over 3 million years. Richard and Mary Leakey have also done significant work in this region. In 2008, two other hominid ancestors were discovered here:

3364-410: Was agreed between the World Bank and the Democratic Republic of the Congo in May 2002. The World Bank agreed to provide $ 90 million of development aid to Democratic Republic of the Congo with the provision that the government did not issue any new concessions granting logging companies rights to exploit the forest. The deal also prohibited the renewal of existing concessions. The government has written

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