Africas Lakes

Africa’s Lakes: Atlas of Our Changing Environment: 

Africa’s Lakes: Atlas of Our Changing Environment Ashbindu Singh United Nations Environment Programme (UNEP) as@rona.unep.org

Africa’s Lakes: Atlas of Our Changing Environment: 

Africa’s Lakes: Atlas of Our Changing Environment

Africa’s Lakes: Atlas of Our Changing Environment: 

Africa’s Lakes: Atlas of Our Changing Environment Objectives Provide visual evidence of changes taking place in African lakes; Communicating scientific information to a wider audience in an engaging fashion; Provide resources to educational community. Assumptions: Trends over time is the most compelling information 'A picture is worth a thousand words' 'Seeing is believing'

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The Shrinking African Continent Population per unit area 1950 - 7 people/km2 1960 - 9 people/km2 1970 - 12 people/km2 1980 - 16 people/km2 1990 - 21 people/km2 2000 - 27 people/km2

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Africa’s Lakes: Atlas of Our Changing Environment Africa’s Lakes Atlas of Our Changing Environment CONTENTS Over 60 Satellite Images Over 40 ground photos 15 Environmental Maps of Africa CONTRIBUTORS 42 Contributors from 16 Organizations and 11 Countries Forest Loss, Invasive Species, Land Degradation, Pollution and Inefficient Irrigation taking their toll

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'Before and after satellite images' Lesotho Highlands Water Project, Lake Nakuru, Kenya Challawa Gorge Dam, Nigeria Lake Kivu, Congo/Rwanda Lake Alaotra, Madagascar Lake Al Wahda, Morocco Lake Cahora Basa, Mozambique Lake Chivero, Zimbabwe Lake Djoudj, Senegal Lake Ichkeul, Tunisia Lake Manantali, Mali Lake Sibaya, South Africa Songor Lagoon, Ghana Lake Tonga, Algeria Africa’s Lakes: Atlas of Our Changing Environment Case studies Lake Chad, Nigeria, Niger, Chad, Cameroon Lake Victoria, Uganda, Kenya, Tanzania Toshka Project, Egypt Africa’s Lakes Atlas of Our Changing Environment

Africa’s Lakes: Atlas of Our Changing Environment: 

Africa’s Lakes: Atlas of Our Changing Environment Africa’s Lakes Atlas of Our Changing Environment Lack of good database makes precise number of lakes in Africa unknown, but according to the WORLDLAKE database, there are 677 lakes in Africa (Minnesota State alone is home to 10 000 Lakes) There are 15 natural lakes that cross the political boundaries of two or more countries in Africa There are 60 transboundary river basins in Africa, covering over 63 per cent of the continent’s land area Lake Chad’s surface area has shrunk by 95 per cent over the past 35 years

Africa’s Lakes: Atlas of Our Changing Environment: 

Africa’s Lakes: Atlas of Our Changing Environment Africa’s Lakes Atlas of Our Changing Environment Uncontrolled damming, the withdrawal of water for irrigation, and climate variability are the major causes of drying up of Lake Tonga in Algeria Population growth around Lake Victoria, the continent’s largest lake, is significantly higher than the rest of Africa Some lakes in central Africa have become known as 'killer lakes,' because of the catastrophic natural events that have occurred in their vicinity

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Shrinkage of Lake Chad Africa’s Lakes Atlas of Our Changing Environment Persistent drought and diversion of water has shrunk the lake to about a tenth of its former size 1972: Larger lake surface area is visible in this image 2001: Impact of drought displays a shrunken lake, comparatively much smaller surface area than in 1972 image

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Lake Victoria: Falling Water Levels Concern for Growing Population Since December 2005, water levels dropped to alarmingly low levels Current water levels in Lake Victoria are below normal and the lowest level since September 1961 The lake is a crucial resource to some 30 million people Lake area is the most densely populated rural region in the world Africa’s Lakes Atlas of Our Changing Environment An estimated 150 000 sq. km. of land have been affected by soil degradation of which 13 per cent has been severely degraded

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Population Growth Around Lake Victoria The population growth around 100 km buffer zone of the Lake Victoria Population growth around Lake Victoria, East Africa, is the highest in Africa 2010 and 2015=Projected Africa’s Lakes Atlas of Our Changing Environment

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Lake Victoria: World’s Fastest Growing Rural Area Africa’s Lakes Atlas of Our Changing Environment Around 1 200 people per sq. km. live in and around the lake; average annual income is US$ 250 per capita

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Population Growth: Lake Victoria vs. Africa Africa’s Lakes Atlas of Our Changing Environment

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Mapping falling water levels of Lake Victoria Source: USDA 2005 Current water levels are below normal and the lowest level since September, 1961 Africa’s Lakes Atlas of Our Changing Environment

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Lake Victoria: Height Variations Source: USDA 2006 Africa’s Lakes Atlas of Our Changing Environment Africa’s largest freshwater lake is now about a meter lower than it was in the early 1990s

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Impact of Invasive Species on Lake Victoria, Uganda 1995: Image shows several water-hyacinth-choked bays (yellow arrows) 2001: A visible reduction of Water Hyacinth from many of the Ugandan bays These images show water hyacinth infestation and control of such invasive species Africa’s Lakes Atlas of Our Changing Environment

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Africa’s Lakes Atlas of Our Changing Environment Lake Kivu: One of Africa’s 'Killer Lakes' These images show dramatic changes before and after the eruption of Mt. Nyiragongo in 2002 2001: Before the January 2002 eruption 2003: Shows the track of the lava flow

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Toshka Lakes: Watering the Desert for Farming Africa’s Lakes Atlas of Our Changing Environment These images show the desert area transformed into vegetable plots 1984-87: Image of the area before the desert reclamation project began in mid-1990s 2000: Four new lakes are visible in this image, faint blue-green areas around the lakes are newly created agricultural lands

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Africa’s Lakes Atlas of Our Changing Environment Toshka Lakes: Watering the Desert for Farming 2005: New fields are clearly visible in the image

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Africa’s Lakes Atlas of Our Changing Environment Lesotho Highland Water Project in South Africa These images show the area before and after construction of Katse dam 1989: Image of the area before the completion of the dam in 1995 2001: Katse dam created an enormous reservoir, the extent of which can clearly be seen in this image

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Africa’s Lakes Atlas of Our Changing Environment Extensive Deforestation Around Lake Nakuru in Kenya These images show the land cover degradation in the lake’s catchment 1973: The area that hosts the world’s largest concentration of flamingos 2000: Excision of forest in the Eastern Mau Forest Reserve (white lines) will most likely lead to disappearance of upper catchment forest cover Decline in lake area from 43 skm to 40 skm in 2000

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Africa’s Lakes Atlas of Our Changing Environment Impact of Challawa Gorge Dam Nigeria These images show the area before and after construction of the dam 1990: Image of the area before the completion of the dam in 1993 1999: Impact of flooding upstream from the dam; colour of the water in the flooded area indicates high sediments

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Africa’s Lakes Atlas of Our Changing Environment Severe Flooding Around Lake Alaotra, Madagascar These images show flooding over a wide area Flooding destroys significant portion of crops Intensive rice irrigation occurs at the western part of the lake (yellow arrows)

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Africa’s Lakes Atlas of Our Changing Environment Impact of Al Wahda reservoir in Morocco These images illustrate the change in land cover 1987: The area before the construction of dams 2001: The area after the construction of large dams

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Africa’s Lakes Atlas of Our Changing Environment Cahora Basa: Mozambique’s Largest Dam on the Zambezi River These images show extraordinary changes in the Zambezi River system as a result of the building of Cahora Basa Dam 1972: The Zambezi River a few years before the dam construction 1999: This image shows part of the enormous dam and the lake

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Africa’s Lakes Atlas of Our Changing Environment Invasive Species in Lake Chivero Zimbabwe These images show overall reduction in water weeds 1989: Weeds show up as green strands along the edges of the lake 2000: This image shows that water weeds remains a persistent problem

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Africa’s Lakes Atlas of Our Changing Environment Ecological Changes Around Lake Ichkeul, Tunisia These images show the impact of damming 1972: Shows the three feeder rivers supplying the lake before they were dammed 2000: Shows the location of the dams (yellow arrows)

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Africa’s Lakes Atlas of Our Changing Environment Agricultural Expansion Around Lake Manantali, Mali These images show the expansion of irrigated agriculture 1977: Shows the original meandering nature of the Bafing River 1999: Shows the expanded irrigated land and increase in lake water quantity

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Africa’s Lakes Atlas of Our Changing Environment Lake Sibaya: Wetland of International Importance in South Africa These images show increase in cultivation around the lake 1991: Lakeshore is home to the only known species of a rare climbing orchid 2001: The yellow arrows vividly show the increase of cultivation of marginal lands around the lake

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Africa’s Lakes Atlas of Our Changing Environment Rapid Shrinking of Lake Songor Lagoon in Ghana These images show a conspicuous reduction in the surface area, partly due to intensive salt production 1990: Appears as solid blue mass of water some 74 sq. km. in size 2000: Water area dramatically reduced to pale shadow Lake is home to fish, globally threatened turtles and important bird populations

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Africa’s Lakes Atlas of Our Changing Environment Changes In and Around Lake Tonga, Algeria These images show the changes brought about by damming of the feeder rivers 1988: Lake Tonga before the damming of feeder rivers 2000: Damming increased irrigation and drastically reduced the volume of water entering the lake

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Africa’s Lakes Atlas of Our Changing Environment Rejuvenation of Djoudj Sanctuary in Senegal These images show the Djoudj Sanctuary before and after the construction of the Diama Dam 23 kilometres from the mouth of the Senegal River 1979: Shows the impact of drought on the Djoudj Sanctuary 1999: Rejuvenation of the Sanctuary wetlands due to significant floods

Africa’s Lakes: Atlas of Our Changing Environment: 

Africa’s Lakes: Atlas of Our Changing Environment Thank You! Free Downloads: www.na.unep.net Purchase: www.Earthprint.com