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Lake Kivu is one of the African Great Lakes. It lies on the border between the Democratic Republic of the Congo and Rwanda, and is in the Albertine Rift, the western branch of the East African Rift. Lake Kivu empties into the Ruzizi River, which flows southwards into Lake Tanganyika. In 1894, German officer and colonial ruler Gustav Adolf von Götzen was the first recorded European to visit the lake.
Lake Kivu | |
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![]() Satellite image of Lake Kivu courtesy of NASA. | |
![]() ![]() Lake Kivu ![]() ![]() Lake Kivu ![]() ![]() Lake Kivu | |
Coordinates | 2°0′S 29°0′E / 2.000°S 29.000°E |
Type | Rift Valley lakes, meromictic, limnically active lake |
Primary outflows | Ruzizi River |
Catchment area | 2,700 km2 (1,000 sq mi) |
Basin countries | Rwanda, Democratic Republic of the Congo |
Max. length | 89 km (55 mi) |
Max. width | 48 km (30 mi) |
Surface area | 2,700 km2 (1,040 sq mi) |
Average depth | 240 m (787 ft) |
Max. depth | 480 m (1,575 ft) |
Water volume | 648 km3 (155 cu mi) |
Surface elevation | 1,460 m (4,790 ft) |
Islands | Idjwi |
Settlements | Goma, Congo Bukavu, Congo Kibuye, Rwanda Cyangugu, Rwanda |
In the past, Lake Kivu drained toward the north, contributing to the White Nile. About 13,000 to 9,000 years ago, volcanic activity blocked Lake Kivu's outlet to the watershed of the Nile. The volcanism produced mountains, including the Virungas, which rose between Lake Kivu and Lake Edward, to the north. Water from Lake Kivu was then forced south down the Ruzizi. This, in turn, raised the level of Lake Tanganyika, which overflowed down the Lukuga River.
Lake Kivu is one of three lakes in the world, along with Lake Nyos and Lake Monoun, that undergo limnic eruptions (where overturn of deepwater stratified layers releases dissolved carbon dioxide (CO2)). The lake's bottom also contains methane (CH4), meaning if a limnic eruption occurs, the lives of the two million people living nearby would be in danger.
Geography
Lake Kivu is approximately 42 km (26 mi) long and 50 km (31 mi) at its widest. Its irregular shape makes measuring its precise surface area difficult; it has been estimated to cover a total surface area of some 2,700 km2 (1,040 sq mi), making it Africa's eighth largest lake. The surface of the lake sits at a height of 1,460 metres (4,790 ft) above sea level. This lake has a chance of suffering a limnic eruption every 1000 years. The lake has a maximum depth of 475 m (1,558 ft) and a mean depth of 220 m (722 ft), making it the world's twentieth deepest lake by maximum depth, and the thirteenth deepest by mean depth.
Some 1,370 square kilometres (529 sq mi) or 58 percent of the lake's waters lie within DRC borders.
The lake bed sits upon a rift valley that is slowly being pulled apart, causing volcanic activity in the area.
The world's tenth-largest island in a lake, Idjwi, lies in Lake Kivu. Settlements on the lake's shore include Bukavu, Kabare, , Sake and Goma in the Democratic Republic of the Congo, and Gisenyi, Kibuye, and Cyangugu in Rwanda.
Chemistry
Lake Kivu is a fresh water lake and, along with Cameroonian Lake Nyos and Lake Monoun, is one of three that are known to undergo limnic eruptions (where overturn of deepwater stratified layers releases dissolved carbon dioxide). Around the lake, geologists[verification needed] found evidence of massive local extinctions about every thousand years, presumably caused by outgassing events. The trigger for lake overturns in Lake Kivu is unknown, but volcanic activity and changes in climate are both suspected. The gaseous chemical composition of exploding lakes is unique to each lake. In Lake Kivu's case, it includes methane (CH4) and carbon dioxide (CO2), as a result of lake water interaction with volcanic hot springs.
The amount of methane contained at the bottom of the lake is estimated to be 65 cubic kilometres (16 cu mi). If burned in a modern combined-cycle generating plant, that amount of methane would generate around 40,000 megawatts for an entire year, which is equivalent to the power output of six Grand Coulee Dams operating at peak springtime power. The lake also holds an estimated 256 cubic kilometres (61 cu mi) of carbon dioxide which, if released in an eruption event, could suffocate all of the inhabitants of the lakeshore. The water temperature is 24 °C (75 °F), and the pH is about 7 in the anoxic region, and around 9 in the oxygenated waters. The methane is reported to be produced by microbial reduction of the volcanic CO2. A future overturn and gas release from the deep waters of Lake Kivu would result in catastrophe, dwarfing the historically documented lake overturns at the much smaller Lakes Nyos and Monoun. The lives of the approximately two million people who live in the lake basin area would be threatened.
Cores from the Bukavu Bay area of the lake reveal that the bottom has layered deposits of the rare mineral monohydrocalcite interlaid with diatoms, on top of sapropelic sediments with high pyrite content. These are found at three different intervals. The sapropelic layers are believed to be related to hydrothermal discharge and the diatoms to a bloom which reduced the carbon dioxide levels low enough to precipitate monohydrocalcite.
Scientists hypothesize that sufficient volcanic interaction with the lake's bottom water that has high gas concentrations would heat water, force the methane out of the water, spark a methane explosion, and trigger a nearly simultaneous release of carbon dioxide, though the entry of 1 million cubic meters of lava during the January 2002 eruption had no effect. The carbon dioxide would then suffocate large numbers of people in the lake basin as the gases roll off the lake surface. It is also possible that the lake could spawn lake tsunamis as gas explodes out of it.
The risk posed by Lake Kivu began to be understood during the analysis of more recent events at Lake Nyos. Lake Kivu's methane was originally thought to be merely a cheap natural resource for export, and for the generation of cheap power. Once the mechanisms that caused lake overturns began to be understood, so did awareness of the risk the lake posed to the local population.
An experimental vent pipe was installed at Lake Nyos in 2001 to remove gas from the deep water, but such a solution for the much larger Lake Kivu would be considerably more expensive. The approximately 510 million metric tons (500×10 6 long tons) of carbon dioxide in the lake is a little under 2 percent of the amount released annually by human fossil fuel burning. Therefore, the process of releasing it could potentially have costs beyond simply building and operating the system.
This problem associated with the prevalence of methane is that of mazuku, the Swahili term "evil wind" for the outgassing of methane and carbon dioxide that kills people and animals, and can even kill vegetation when in high enough concentration.
Methane extraction
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Lake Kivu has recently been found to contain approximately 55 billion m3 (1.9 trillion cu ft) of dissolved biogas at a depth of 300 metres (1,000 ft). Until 2004, extraction of the gas was done on a small scale, with the extracted gas being used to run boilers at the Bralirwa brewery in Gisenyi. As far as large-scale exploitation of this resource is concerned, the Rwandan government has negotiated with a number of parties to extract methane from the lake.
In 2011 ContourGlobal, a UK-based energy company focused on emerging markets, secured project financing to initiate a large-scale methane extraction project. The project is run through a local Rwandan entity called KivuWatt, using an offshore barge platform to extract, separate, and clean the gasses obtained from the lake bed before pumping purified methane via an underwater pipeline to onshore gas engines. Stage one of the project, powering three "gensets" along the lake shore and supplying 26 MW of electricity to the local grid, has been completed. The next phase aims to deploy nine additional gensets at 75 MW to create a total capacity of 101 MW.
In addition, Symbion Power Lake Kivu Limited was awarded a Concession and Power Producing Agreement (PPA) in 2015, to produce 50 MW of power using Lake Kivu methane. The project was expected to commence construction in 2019, with first power (Phase 1 - 14 MW) to be produced in first quarter 2020. The plant was planned to be fully operational in 2021.[needs update]
Symbion Power has purchased another concession for a further 25 MW and are currently negotiating a PPA with the Rwanda Electricity Group which may see 8 MW of power dispatched to the Grid six months after the PPA has been signed. This concession is on the site of the original pilot plant known as KP1.[needs update]
In addition to managing gas extraction, KivuWatt will also manage the electrical generation plants and on-sell the electrical power to the Rwandan government under the terms of a long-term Power Purchase Agreement (PPA). This allows KivuWatt to control a vertically integrated energy offering from point of extraction to point of sale into the local grid. Extraction is said to be cost-effective and relatively simple because once the gas-rich water is pumped up, the dissolved gases (primarily carbon dioxide, hydrogen sulfide and methane) begin to bubble out as the water pressure gets lower. This project is expected to increase Rwanda's energy generation capability by as much as 20 times, and will enable Rwanda to sell electricity to neighbouring African countries. The firm was awarded the 2011 Africa Power deal of the year for innovation in the financing arrangements it obtained from various sources for the KivuWatt project. The $200 million power plant was operating at 26 MW in 2016.
Biology and fisheries
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The fish fauna in Lake Kivu is relatively poor with 28 described species, including four introduced species. The natives are the Lake Rukwa minnow (Raiamas moorii), four species of barb (ripon barbel, Barbus altianalis, East African red-finned barb, Enteromius apleurogramma, redspot barb, E. kerstenii and Pellegrin's barb, E. pellegrini), an Amphilius catfish, two Clarias catfish ( and C. gariepinus), Nile tilapia (Oreochromis niloticus) and 15 endemic Haplochromis cichlids. Another c. 20 possibly undescribed species of cichlids are known from the lake. The introduced species are three cichlids, the longfin tilapia (Oreochromis macrochir), blue-spotted tilapia (O. leucostictus) and redbreast tilapia (Coptodon rendalli), and a clupeid, the Lake Tanganyika sardine (Limnothrissa miodon) The sardine is referred to locally as 'Ndagala' or 'Isambaza'.
The exploitable stock of the Lake Tanganyika sardine was estimated at 2,000–4,000 metric tons (2,000–3,900 long tons) per year. It was introduced to Lake Kivu in late 1959 by the Belgian agronomist Alphonse Collart. An attempt to introduce the similar Lake Tanganyika sprat (Stolothrissa tanganicae) at the same time was unsuccessful.
At present, Lake Kivu is the sole natural lake in which L. miodon, a sardine originally restricted to Lake Tanganyika, has been introduced initially to fill an empty niche. Prior to the introduction, no planktivorous fish was present in the pelagic waters of Lake Kivu. In the early 1990s, the number of fishers on the lake was 6,563, of which 3,027 were associated with the pelagic fishery and 3,536 with the traditional fishery. The widespread armed conflict in the surrounding region from the mid-1990s resulted in a decline in the fisheries harvest.
Following this introduction, the sardine has gained substantial economic and nutritional importance for the lakeside human population but from an ecosystem standpoint, the introduction of planktivorous fish may result in important modifications of plankton community structure. Recent observations showed the disappearance during the last decades of a large grazer, , and the dominance of mesozooplankton community by three species of cyclopoid copepod: , and .
The first comprehensive phytoplankton survey was released in 2006. With an annual average chlorophyll in the mixed layer of 2.2 mg m−3 and low nutrient levels in the euphotic zone, the lake is clearly oligotrophic. Diatoms are the dominant group in the lake, particularly during the dry season episodes of deep mixing. During the rainy season, the stratified water column, with high light and lower nutrient availability, favour dominance of cyanobacteria with high numbers of phototrophic picoplankton. The actual primary production is 0.71 g C m−2 d−1 (≈ 260 g C m−2 a−1).
A study of evolutionary genetics showed that the cichlids from lakes in northern Virunga (e.g., Edward, George, Victoria) would have evolved in a "proto-lake Kivu", much older than the intense volcanic activity (20,000-25,000 years ago) which cut the connection. The elevation of the mountains west of the lake (which is currently the Kahuzi-Biega National Park, one of the largest reserves of eastern lowland (or Grauer's) gorillas in the world), combined with the elevation of the eastern rift (located in eastern Rwanda) would be responsible for the drainage of water from central Rwanda in the actual Lake Kivu. This concept of "proto-lake Kivu" was challenged by lack of consistent geological evidence, although the cichlid's molecular clock suggests the existence of a lake much older than the commonly cited 15,000 years.
Lake Kivu is the home of four species of freshwater crab, including two non-endemics (Potamonautes lirrangensis and P. mutandensis) and two endemics ( and ). Among Rift Valley lakes, Lake Tanganyika and Lake Victoria are the only other with endemic freshwater crabs.
Illegal fishing
In 2018, over 400 cases of potential illegal fishing were recorded on Lake Kivu. According to the Animal Research and Technology Transfer at the Rwanda Agricultural Board, fish production in Kivu Lake dropped from 24,199 tonnes in the 2017–2018 fishing season to 16,194 tonnes in 2019–2020, which Deputy Director Solange Uwituze attributed to fishing methods that affect fish reproduction. Between May and July 2020, Rwanda Police Marine Unit operations reported 27 cases including 10 arrested poachers for illegal fishing on the lake.
Gallery
- Lake Kivu from Sake, Goma, D R Congo
- Lake Kivu with Goma in the background, Congo
- Lake Kivu separating Bukavu (In the foreground) and Cyangugu (In the background) as seen from Tumbimbi.
See also
- Gasmeth Energy Gas Works
- Limnic eruption
- Mazuku
- Meromictic lake
References
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(help) - Collart, A. (1960). "L'introduction du 'Stolothrissa tanganicae' (Ndagala) au lac Kivu". Bulletin Agricole du Congo Belge. Hosted at Agricultural Research Archive for DRC, Rwanda and Burundi, 1885-1960 (in French). 51 (4).
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Lake Kivu is one of the African Great Lakes It lies on the border between the Democratic Republic of the Congo and Rwanda and is in the Albertine Rift the western branch of the East African Rift Lake Kivu empties into the Ruzizi River which flows southwards into Lake Tanganyika In 1894 German officer and colonial ruler Gustav Adolf von Gotzen was the first recorded European to visit the lake Lake KivuSatellite image of Lake Kivu courtesy of NASA Lake KivuShow map of Democratic Republic of the CongoLake KivuShow map of RwandaLake KivuShow map of AfricaCoordinates2 0 S 29 0 E 2 000 S 29 000 E 2 000 29 000TypeRift Valley lakes meromictic limnically active lakePrimary outflowsRuzizi RiverCatchment area2 700 km2 1 000 sq mi Basin countriesRwanda Democratic Republic of the CongoMax length89 km 55 mi Max width48 km 30 mi Surface area2 700 km2 1 040 sq mi Average depth240 m 787 ft Max depth480 m 1 575 ft Water volume648 km3 155 cu mi Surface elevation1 460 m 4 790 ft IslandsIdjwiSettlementsGoma Congo Bukavu Congo Kibuye Rwanda Cyangugu RwandaKivu lake shoreline at Gisenyi Rwanda In the past Lake Kivu drained toward the north contributing to the White Nile About 13 000 to 9 000 years ago volcanic activity blocked Lake Kivu s outlet to the watershed of the Nile The volcanism produced mountains including the Virungas which rose between Lake Kivu and Lake Edward to the north Water from Lake Kivu was then forced south down the Ruzizi This in turn raised the level of Lake Tanganyika which overflowed down the Lukuga River Lake Kivu is one of three lakes in the world along with Lake Nyos and Lake Monoun that undergo limnic eruptions where overturn of deepwater stratified layers releases dissolved carbon dioxide CO2 The lake s bottom also contains methane CH4 meaning if a limnic eruption occurs the lives of the two million people living nearby would be in danger GeographyLake Kivu is approximately 42 km 26 mi long and 50 km 31 mi at its widest Its irregular shape makes measuring its precise surface area difficult it has been estimated to cover a total surface area of some 2 700 km2 1 040 sq mi making it Africa s eighth largest lake The surface of the lake sits at a height of 1 460 metres 4 790 ft above sea level This lake has a chance of suffering a limnic eruption every 1000 years The lake has a maximum depth of 475 m 1 558 ft and a mean depth of 220 m 722 ft making it the world s twentieth deepest lake by maximum depth and the thirteenth deepest by mean depth Some 1 370 square kilometres 529 sq mi or 58 percent of the lake s waters lie within DRC borders The lake bed sits upon a rift valley that is slowly being pulled apart causing volcanic activity in the area The world s tenth largest island in a lake Idjwi lies in Lake Kivu Settlements on the lake s shore include Bukavu Kabare Sake and Goma in the Democratic Republic of the Congo and Gisenyi Kibuye and Cyangugu in Rwanda ChemistryLake Kivu is a fresh water lake and along with Cameroonian Lake Nyos and Lake Monoun is one of three that are known to undergo limnic eruptions where overturn of deepwater stratified layers releases dissolved carbon dioxide Around the lake geologists verification needed found evidence of massive local extinctions about every thousand years presumably caused by outgassing events The trigger for lake overturns in Lake Kivu is unknown but volcanic activity and changes in climate are both suspected The gaseous chemical composition of exploding lakes is unique to each lake In Lake Kivu s case it includes methane CH4 and carbon dioxide CO2 as a result of lake water interaction with volcanic hot springs The amount of methane contained at the bottom of the lake is estimated to be 65 cubic kilometres 16 cu mi If burned in a modern combined cycle generating plant that amount of methane would generate around 40 000 megawatts for an entire year which is equivalent to the power output of six Grand Coulee Dams operating at peak springtime power The lake also holds an estimated 256 cubic kilometres 61 cu mi of carbon dioxide which if released in an eruption event could suffocate all of the inhabitants of the lakeshore The water temperature is 24 C 75 F and the pH is about 7 in the anoxic region and around 9 in the oxygenated waters The methane is reported to be produced by microbial reduction of the volcanic CO2 A future overturn and gas release from the deep waters of Lake Kivu would result in catastrophe dwarfing the historically documented lake overturns at the much smaller Lakes Nyos and Monoun The lives of the approximately two million people who live in the lake basin area would be threatened Cores from the Bukavu Bay area of the lake reveal that the bottom has layered deposits of the rare mineral monohydrocalcite interlaid with diatoms on top of sapropelic sediments with high pyrite content These are found at three different intervals The sapropelic layers are believed to be related to hydrothermal discharge and the diatoms to a bloom which reduced the carbon dioxide levels low enough to precipitate monohydrocalcite Scientists hypothesize that sufficient volcanic interaction with the lake s bottom water that has high gas concentrations would heat water force the methane out of the water spark a methane explosion and trigger a nearly simultaneous release of carbon dioxide though the entry of 1 million cubic meters of lava during the January 2002 eruption had no effect The carbon dioxide would then suffocate large numbers of people in the lake basin as the gases roll off the lake surface It is also possible that the lake could spawn lake tsunamis as gas explodes out of it The risk posed by Lake Kivu began to be understood during the analysis of more recent events at Lake Nyos Lake Kivu s methane was originally thought to be merely a cheap natural resource for export and for the generation of cheap power Once the mechanisms that caused lake overturns began to be understood so did awareness of the risk the lake posed to the local population An experimental vent pipe was installed at Lake Nyos in 2001 to remove gas from the deep water but such a solution for the much larger Lake Kivu would be considerably more expensive The approximately 510 million metric tons 500 10 6 long tons of carbon dioxide in the lake is a little under 2 percent of the amount released annually by human fossil fuel burning Therefore the process of releasing it could potentially have costs beyond simply building and operating the system This problem associated with the prevalence of methane is that of mazuku the Swahili term evil wind for the outgassing of methane and carbon dioxide that kills people and animals and can even kill vegetation when in high enough concentration Methane extraction A methane extraction platform Gisenyi Rwanda Lake Kivu has recently been found to contain approximately 55 billion m3 1 9 trillion cu ft of dissolved biogas at a depth of 300 metres 1 000 ft Until 2004 extraction of the gas was done on a small scale with the extracted gas being used to run boilers at the Bralirwa brewery in Gisenyi As far as large scale exploitation of this resource is concerned the Rwandan government has negotiated with a number of parties to extract methane from the lake In 2011 ContourGlobal a UK based energy company focused on emerging markets secured project financing to initiate a large scale methane extraction project The project is run through a local Rwandan entity called KivuWatt using an offshore barge platform to extract separate and clean the gasses obtained from the lake bed before pumping purified methane via an underwater pipeline to onshore gas engines Stage one of the project powering three gensets along the lake shore and supplying 26 MW of electricity to the local grid has been completed The next phase aims to deploy nine additional gensets at 75 MW to create a total capacity of 101 MW In addition Symbion Power Lake Kivu Limited was awarded a Concession and Power Producing Agreement PPA in 2015 to produce 50 MW of power using Lake Kivu methane The project was expected to commence construction in 2019 with first power Phase 1 14 MW to be produced in first quarter 2020 The plant was planned to be fully operational in 2021 needs update Symbion Power has purchased another concession for a further 25 MW and are currently negotiating a PPA with the Rwanda Electricity Group which may see 8 MW of power dispatched to the Grid six months after the PPA has been signed This concession is on the site of the original pilot plant known as KP1 needs update In addition to managing gas extraction KivuWatt will also manage the electrical generation plants and on sell the electrical power to the Rwandan government under the terms of a long term Power Purchase Agreement PPA This allows KivuWatt to control a vertically integrated energy offering from point of extraction to point of sale into the local grid Extraction is said to be cost effective and relatively simple because once the gas rich water is pumped up the dissolved gases primarily carbon dioxide hydrogen sulfide and methane begin to bubble out as the water pressure gets lower This project is expected to increase Rwanda s energy generation capability by as much as 20 times and will enable Rwanda to sell electricity to neighbouring African countries The firm was awarded the 2011 Africa Power deal of the year for innovation in the financing arrangements it obtained from various sources for the KivuWatt project The 200 million power plant was operating at 26 MW in 2016 Biology and fisheriesFishing boats on Lake Kivu 2009Paradis Malahide Island within the lakeThe sky reflected on Lake Kivu The fish fauna in Lake Kivu is relatively poor with 28 described species including four introduced species The natives are the Lake Rukwa minnow Raiamas moorii four species of barb ripon barbel Barbus altianalis East African red finned barb Enteromius apleurogramma redspot barb E kerstenii and Pellegrin s barb E pellegrini an Amphilius catfish two Clarias catfish and C gariepinus Nile tilapia Oreochromis niloticus and 15 endemic Haplochromis cichlids Another c 20 possibly undescribed species of cichlids are known from the lake The introduced species are three cichlids the longfin tilapia Oreochromis macrochir blue spotted tilapia O leucostictus and redbreast tilapia Coptodon rendalli and a clupeid the Lake Tanganyika sardine Limnothrissa miodon The sardine is referred to locally as Ndagala or Isambaza The exploitable stock of the Lake Tanganyika sardine was estimated at 2 000 4 000 metric tons 2 000 3 900 long tons per year It was introduced to Lake Kivu in late 1959 by the Belgian agronomist Alphonse Collart An attempt to introduce the similar Lake Tanganyika sprat Stolothrissa tanganicae at the same time was unsuccessful At present Lake Kivu is the sole natural lake in which L miodon a sardine originally restricted to Lake Tanganyika has been introduced initially to fill an empty niche Prior to the introduction no planktivorous fish was present in the pelagic waters of Lake Kivu In the early 1990s the number of fishers on the lake was 6 563 of which 3 027 were associated with the pelagic fishery and 3 536 with the traditional fishery The widespread armed conflict in the surrounding region from the mid 1990s resulted in a decline in the fisheries harvest Following this introduction the sardine has gained substantial economic and nutritional importance for the lakeside human population but from an ecosystem standpoint the introduction of planktivorous fish may result in important modifications of plankton community structure Recent observations showed the disappearance during the last decades of a large grazer and the dominance of mesozooplankton community by three species of cyclopoid copepod and The first comprehensive phytoplankton survey was released in 2006 With an annual average chlorophyll in the mixed layer of 2 2 mg m 3 and low nutrient levels in the euphotic zone the lake is clearly oligotrophic Diatoms are the dominant group in the lake particularly during the dry season episodes of deep mixing During the rainy season the stratified water column with high light and lower nutrient availability favour dominance of cyanobacteria with high numbers of phototrophic picoplankton The actual primary production is 0 71 g C m 2 d 1 260 g C m 2 a 1 A study of evolutionary genetics showed that the cichlids from lakes in northern Virunga e g Edward George Victoria would have evolved in a proto lake Kivu much older than the intense volcanic activity 20 000 25 000 years ago which cut the connection The elevation of the mountains west of the lake which is currently the Kahuzi Biega National Park one of the largest reserves of eastern lowland or Grauer s gorillas in the world combined with the elevation of the eastern rift located in eastern Rwanda would be responsible for the drainage of water from central Rwanda in the actual Lake Kivu This concept of proto lake Kivu was challenged by lack of consistent geological evidence although the cichlid s molecular clock suggests the existence of a lake much older than the commonly cited 15 000 years Lake Kivu is the home of four species of freshwater crab including two non endemics Potamonautes lirrangensis and P mutandensis and two endemics and Among Rift Valley lakes Lake Tanganyika and Lake Victoria are the only other with endemic freshwater crabs Illegal fishing In 2018 over 400 cases of potential illegal fishing were recorded on Lake Kivu According to the Animal Research and Technology Transfer at the Rwanda Agricultural Board fish production in Kivu Lake dropped from 24 199 tonnes in the 2017 2018 fishing season to 16 194 tonnes in 2019 2020 which Deputy Director Solange Uwituze attributed to fishing methods that affect fish reproduction Between May and July 2020 Rwanda Police Marine Unit operations reported 27 cases including 10 arrested poachers for illegal fishing on the lake GalleryLake Kivu from Sake Goma D R Congo Lake Kivu with Goma in the background Congo Lake Kivu separating Bukavu In the foreground and Cyangugu In the background as seen from Tumbimbi See alsoGasmeth Energy Gas Works Limnic eruption Mazuku Meromictic lakeReferencesLagasse Paul ed 2000 The Columbia Encyclopedia 6 ed Columbia University Press p 1539 ISBN 978 0787650759 Scheffel Richard L Wernet Susan J eds 1980 Natural Wonders of the World United States of America Reader s Digest Association Inc pp 206 207 ISBN 978 0 89577 087 5 Wong H K Herzen R P 1974 06 01 A Geophysical Study of Lake Kivu East Africa Geophysical Journal International 37 3 371 389 doi 10 1111 j 1365 246x 1974 tb04091 x ISSN 0956 540X The Largest Lakes in Africa WorldAtlas 15 June 2020 Danley Patrick D Husemann Martin Ding Baoqing Dipietro Lyndsay M Beverly Emily J Peppe Daniel J et al 2012 The Impact of the Geologic History and Paleoclimate on the Diversification of East African Cichlids International Journal of Evolutionary Biology 2012 1 20 doi 10 1155 2012 574851 PMC 3408716 PMID 22888465 Clark J D 1969 Kalambo Falls Prehistoric Site Volume 1 London Cambridge University Press p 34 Retrieved 16 January 2013 Geology com Archived from the original on 2019 10 07 Fowkes Neville Mason David Hutchinson A J 2018 Proceedings of the Mathematics in Industry Study Group Emissions from Lake Kivu PDF University of the Witwatersrand pp 27 73 ISBN 978 0 9870336 8 0 Retrieved 11 October 2022 Wenz John 2020 The danger lurking in an African lake Knowable Magazine doi 10 1146 knowable 100720 1 S2CID 225118318 The Explosive Hazard Hiding in an African Lake Smithsonian Magazine Njala University Sierra Leone Olapade Oj Omitoyin Bo University of Ibadan Nigeria 2012 08 03 Anthropogenic pollution impact on physico chemical characteristics of Lake Kivu Rwanda African Journal of Food Agriculture Nutrition and Development 12 53 6517 6536 doi 10 18697 ajfand 53 9840 hdl 1807 55851 Nayar Anjali 2009 A lakeful of trouble Nature 460 7253 321 323 doi 10 1038 460321a PMID 19606123 Stoffers P and Fischbeck R 1974 Monohydrocalcite in the sediments of Lake Kivu East Africa Sedimentology 21 163 170 Seach John January 17 25 2002 Archived Volcano News John Seach volcanolive com Retrieved 2023 02 07 Halbwachs et al 2002 03 09 Investigations in Lake Kivu East Central Africa after the Nyiragongo Eruption of January 2002 Specific study of the impact of the sub water lava inflow on the lake stability PDF Solidarities Retrieved 2012 12 21 mirror Rwanda and DRC Sign Agreement Over L Kivu Methane Gas Exploration newsghana com gh November 21 2015 Retrieved 2023 02 07 Killer Lakes Transcript BBC April 4 2002 Retrieved 2023 02 07 In the Shadow of Doom Archived 2007 09 28 at the Wayback Machine The Walrus May 2006 Case Studies Recovery of Gas from Lake Kivu The Goats of Rwanda Archived 2006 02 24 at the Wayback Machine Added Value Engineering Consultants accessed 4 May 2007 Adam Mynott May 4 2007 Rwanda s Underwater Powerhouse BBC News Retrieved 2008 02 05 Assets KivuWatt ContourGlobal Retrieved 2018 04 02 Archived copy Archived from the original on 2018 05 05 Retrieved 2018 05 04 a href wiki Template Cite web title Template Cite web cite web a CS1 maint archived copy as title link Energy Division MININFRA Retrieved July 14 2021 Methane gas project gets global award www rwandaenergy com Retrieved 7 March 2012 African power deal of the year 2011 KivuWatt www projectfinancemagazine com Retrieved 7 March 2012 Rwanda Inaugurates Groundbreaking Methane Power Project MIT Technology Review Snoeks J De Vos L Thys van den Audenaerde D 1997 The ichthyogeography of lake Kivu South African Journal of Science 93 579 584 Walker J 2013 How many species are there in Lake Kivu PDF University of Bern a href wiki Template Cite journal title Template Cite journal cite journal a Cite journal requires journal help Collart A 1960 L introduction du Stolothrissa tanganicae Ndagala au lac Kivu Bulletin Agricole du Congo Belge Hosted at Agricultural Research Archive for DRC Rwanda and Burundi 1885 1960 in French 51 4 Capart A 1959 A propos de l introduction du Ndakala Stolothrissa tanganikae dans le lac Kivu Bulletin Agricole du Congo Belge et du Ruanda Burundi in French 50 4 Collart Alphonse June 1989 Introduction et acclimatation de l Isambaza du lac Tanganyika au lac Kivu Compte rendu du seminaire trente ans apres l introduction de l Isambaza au lac Kivu RWA 87 012 DOC TR 16 in French Gisenyi Rwanda Food and Agriculture Organization of the United Nations Marshall B E 1991 Seasonal and annual variations in the abundance of the clupeid Limnothrissa miodon in lake Kivu Journal of Fish Biology 39 5 641 648 doi 10 1111 j 1095 8649 1991 tb04394 x INFORMATION ON FISHERIES MANAGEMENT IN THE DEMOCRATIC REPUBLIC OF THE CONGO fao org January 2001 Archived from the original on March 15 2006 Retrieved June 26 2023 Isumbisho M 2006 Zooplankton ecology of Lake Kivu Eastern Africa Belgium University of Namur ISBN 978 2 87037 534 1 Isumbisho M Sarmento H Kaningini B Micha J C Descy J P 2006 Zooplankton of Lake Kivu East Africa half a century after the Tanganyika sardine introduction PDF Journal of Plankton Research 28 11 971 989 doi 10 1093 plankt fbl032 Sarmento H 2006 Phytoplankton ecology of Lake Kivu Eastern Africa PDF Belgium University of Namur ISBN 978 2 87037 532 7 Archived from the original PDF on 2016 01 17 Retrieved 2011 04 23 Sarmento H Isumbisho M Descy JP 2006 Phytoplankton ecology of Lake Kivu eastern Africa PDF Journal of Plankton Research 28 9 815 829 doi 10 1093 plankt fbl017 Sarmento H et al 2008 Abundance and distribution of picoplankton in tropical oligotrophic Lake Kivu eastern Africa PDF Freshwater Biology 53 4 756 771 doi 10 1111 j 1365 2427 2007 01939 x Sarmento H et al 2007 Species diversity of pelagic algae of Lake Kivu East Africa PDF Cryptogamie Algologie 28 3 245 269 Sarmento H et al 2009 Phytoplankton ecology of Lake Kivu eastern Africa biomass production and elemental ratios PDF International Association of Theoretical and Applied Limnology Vol 30 Pt 5 Proceedings 30 709 713 Verheyen E 2003 Origin of the Superflock of Cichlid Fishes from Lake Victoria East Africa Science 300 5617 325 329 Bibcode 2003Sci 300 325V CiteSeerX 10 1 1 584 2497 doi 10 1126 science 1080699 PMID 12649486 S2CID 84478005 Stager J C 2003 Comment on Origin of the Superflock of Cichlid Fishes from Lake Victoria East Africa Science 304 5673 963b doi 10 1126 science 1091978 PMID 15143263 Cumberlidge N and Meyer K S 2011 A revision of the freshwater crabs of Lake Kivu East Africa Journal Articles Paper 30 Cumberlidge N and P F Clark 2017 Description of three new species of Potamonautes MacLeay 1838 from the Lake Victoria region in southern Uganda East Africa Brachyura Potamoidea Potamonautidae European Journal of Taxonomy 371 1 19 doi 10 5852 ejt 2017 371 Illicit fishing threatens biodiversity in Lake Kivu 26 January 2021 Retrieved 2023 06 23 ENACTAfrica org 2022 01 31 Tipping the scales of illicit fishing in Lake Kivu ENACT Africa Retrieved 2022 03 24 ISSAfrica org 2022 02 02 Tipping the scales of illicit fishing in Lake Kivu ISS Africa Retrieved 2022 03 24 Wikimedia Commons has media related to Lake Kivu