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Ningu
The ningu (''Labeo victorianus'') is a species of ray-finned fish in the family Cyprinidae. It is found in the Lake Victoria basin in Burundi, Kenya, Tanzania, and Uganda. Its natural habitats are rivers, swamps, freshwater lakes, freshwater marshes, and inland deltas. It is threatened by a loss of habitat due to pollution, siltation and drainage as agriculture expands in the Lake Victoria basin, by overfishing Overfishing is the removal of a species of fish (i.e. fishing) from a body of water at a rate greater than that the species can replenish its population naturally (i.e. the overexploitation of the fishery's existing fish stock), resulting in th ... on their breeding migrations and by introduced alien fish. References Labeo Fish described in 1901 Taxonomy articles created by Polbot {{Labeoninae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Victoria
Lake Victoria is one of the African Great Lakes. With a surface area of approximately , Lake Victoria is Africa's largest lake by area, the world's largest tropical lake, and the world's second-largest fresh water lake by surface area after Lake Superior in North America. In terms of volume, Lake Victoria is the world's ninth-largest continental lake, containing about of water. Lake Victoria occupies a shallow depression in Africa. The lake has an average depth of and a maximum depth of .United Nations, ''Development and Harmonisation of Environmental Laws Volume 1: Report on the Legal and Institutional Issues in the Lake Victoria Basin'', United Nations, 1999, page 17 Its catchment area covers . The lake has a shoreline of when digitized at the 1:25,000 level, with islands constituting 3.7% of this length. The lake's area is divided among three countries: Kenya occupies 6% (), Uganda 45% (), and Tanzania 49% (). Though having multiple local language names ( luo, Nam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Labeo
''Labeo'' is a genus of carps in the family Cyprinidae. They are found in freshwater habitats in the tropics and subtropics of Africa and Asia. It contains the typical labeos in the subfamily Labeoninae, which may not be a valid group, however, and is often included in the Cyprininae as tribe Labeonini. If the Labeoninae are accepted as distinct, Labeonini is the name of the tribe in this subfamily to which the labeos belong. If the Labeonini are considered a tribe of the Cyprininae, the labeos are placed in subtribe Labeoina. The labeos appear fairly similar to the " freshwater sharks" of the genus ''Epalzeorhynchos'', which is also part of the Labeoninae (or Labeonini), but is not very closely related. Labeos are larger, and have a more spindle-shaped body, as they are mostly free-swimming rather than benthic like ''Epalzeorhynchos''. Their mouths look very different, too; they have a pronounced rostral cap, which covers the upper lip except when feeding. The lips are expande ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
George Albert Boulenger
George Albert Boulenger (19 October 1858 – 23 November 1937) was a Belgian-British zoologist who described and gave scientific names to over 2,000 new animal species, chiefly fish, reptiles, and amphibians. Boulenger was also an active botanist during the last 30 years of his life, especially in the study of roses. Life Boulenger was born in Brussels, Belgium, the only son of Gustave Boulenger, a Belgian public notary, and Juliette Piérart, from Valenciennes. He graduated in 1876 from the Free University of Brussels with a degree in natural sciences, and worked for a while at the Royal Belgian Institute of Natural Sciences, Brussels, as an assistant naturalist studying amphibians, reptiles, and fishes. He also made frequent visits during this time to the ''Muséum national d'Histoire naturelle'' in Paris and the British Museum in London. In 1880, he was invited to work at the Natural History Museum, then a department of the British Museum, by Dr. Albert C. L. G. Günther a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake
A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much larger oceans, they do form part of the Earth's water cycle. Lakes are distinct from lagoons, which are generally coastal parts of the ocean. Lakes are typically larger and deeper than ponds, which also lie on land, though there are no official or scientific definitions. Lakes can be contrasted with rivers or streams, which usually flow in a channel on land. Most lakes are fed and drained by rivers and streams. Natural lakes are generally found in mountainous areas, rift zones, and areas with ongoing glaciation. Other lakes are found in endorheic basins or along the courses of mature rivers, where a river channel has widened into a basin. Some parts of the world have many lakes formed by the chaotic drainage patterns left over from the la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Overfishing
Overfishing is the removal of a species of fish (i.e. fishing) from a body of water at a rate greater than that the species can replenish its population naturally (i.e. the overexploitation of the fishery's existing fish stock), resulting in the species becoming increasingly underpopulated in that area. Overfishing can occur in water bodies of any sizes, such as ponds, wetlands, rivers, lakes or oceans, and can result in resource depletion, reduced biological growth rates and low biomass levels. Sustained overfishing can lead to critical depensation, where the fish population is no longer able to sustain itself. Some forms of overfishing, such as the overfishing of sharks, has led to the upset of entire marine ecosystems. Types of overfishing include: growth overfishing, recruitment overfishing, ecosystem overfishing. The ability of a fishery to recover from overfishing depends on whether its overall carrying capacity and the variety of ecological conditions are suitable for t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agricultural Expansion
Agricultural expansion describes the growth of agricultural land (arable land, pastures, etc.) especially in the 20th and 21st centuries. The agricultural expansion is often explained as a direct consequence of the global increase in food and energy requirements due to continuing population growth (both which in turn have been attributed to agricultural expansion itself), with an estimated expectation of 10 to 11 billion humans on Earth by end of this century. It is foreseen that most of the world's non-agrarian ecosystems (terrestrial and aquatic) will be affected adversely, from habitat loss, land degradation, overexploitation, and other problems. The intensified food (and biofuel) production will in particular affect the tropical regions. Most modern agriculture relies on intensive methods. Further expansion of the predominant farming types that rest on a small number of highly productive crops has led to a significant loss of biodiversity on a global scale already. More ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drainage
Drainage is the natural or artificial removal of a surface's water and sub-surface water from an area with excess of water. The internal drainage of most agricultural soils is good enough to prevent severe waterlogging (anaerobic conditions that harm root growth), but many soils need artificial drainage to improve production or to manage water supplies. History Early history The Indus Valley civilization had sewerage and drainage systems. All houses in the major cities of Harappa and Mohenjo-daro had access to water and drainage facilities. Waste water was directed to covered gravity sewers, which lined the major streets. 18th and 19th century The invention of hollow-pipe drainage is credited to Sir Hugh Dalrymple, who died in 1753. Current practices Geotextiles New storm water drainage systems incorporate geotextile filters that retain and prevent fine grains of soil from passing into and clogging the drain. Geotextiles are synthetic textile fabrics specially ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siltation
Siltation, is water pollution caused by particulate terrestrial clastic material, with a particle size dominated by silt or clay. It refers both to the increased concentration of suspended sediments and to the increased accumulation (temporary or permanent) of fine sediments on bottoms where they are undesirable. Siltation is most often caused by soil erosion or sediment spill. It is sometimes referred to by the ambiguous term "sediment pollution", which can also refer to a chemical contamination of sediments accumulated on the bottom, or to pollutants bound to sediment particles. Although "siltation" is not perfectly stringent, since it also includes particle sizes other than silt, it is preferred for its lack of ambiguity. Causes The origin of the increased sediment transport into an area may be erosion on land or activities in the water. In rural areas, the erosion source is typically soil degradation by intensive or inadequate agricultural practices, leading to soil eros ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water Pollution
Water pollution (or aquatic pollution) is the contamination of water bodies, usually as a result of human activities, so that it negatively affects its uses. Water bodies include lakes, rivers, oceans, aquifers, reservoirs and groundwater. Water pollution results when contaminants are introduced into these water bodies. Water pollution can be attributed to one of four sources: sewage discharges, industrial activities, agricultural activities, and urban runoff including stormwater. It can be grouped into surface water pollution (either fresh water pollution or marine pollution) or groundwater pollution. For example, releasing inadequately treated wastewater into natural waters can lead to degradation of these aquatic ecosystems. Water pollution can also lead to water-borne diseases for people using polluted water for drinking, bathing, washing or irrigation. Water pollution reduces the ability of the body of water to provide the ecosystem services (such as drinking water) that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loss Of Habitat
Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby reducing biodiversity and species abundance. Habitat destruction is the leading cause of biodiversity loss. Fragmentation and loss of habitat have become one of the most important topics of research in ecology as they are major threats to the survival of endangered species. Activities such as harvesting natural resources, industrial production and urbanization are human contributions to habitat destruction. Pressure from agriculture is the principal human cause. Some others include mining, logging, trawling, and urban sprawl. Habitat destruction is currently considered the primary cause of species extinction worldwide. Environmental factors can contribute to habitat destruction more indirectly. Geological processes, climate change, introdu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
River Delta
A river delta is a landform shaped like a triangle, created by deposition (geology), deposition of sediment that is carried by a river and enters slower-moving or stagnant water. This occurs where a river enters an ocean, sea, estuary, lake, reservoir, or (more rarely) another river that cannot carry away the supplied sediment. It is so named because its triangle shape resembles the Greek letter Delta. The size and shape of a delta is controlled by the balance between watershed processes that supply sediment, and receiving basin processes that redistribute, sequester, and export that sediment. The size, geometry, and location of the receiving basin also plays an important role in delta evolution. River deltas are important in human civilization, as they are major agricultural production centers and population centers. They can provide Coast, coastline defense and can impact drinking water supply. They are also Ecology, ecologically important, with different species' assemblages ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marsh
A marsh is a wetland that is dominated by herbaceous rather than woody plant species.Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). Cambridge University Press, Cambridge, UK. 497 p Marshes can often be found at the edges of lakes and streams, where they form a transition between the aquatic and terrestrial ecosystems. They are often dominated by grasses, rushes or reeds. If woody plants are present they tend to be low-growing shrubs, and the marsh is sometimes called a carr. This form of vegetation is what differentiates marshes from other types of wetland such as swamps, which are dominated by trees, and mires, which are wetlands that have accumulated deposits of acidic peat. Marshes provide habitats for many kinds of invertebrates, fish, amphibians, waterfowl and aquatic mammals. This biological productivity means that marshes contain 0.1% of global sequestered terrestrial carbon. Moreover, they have an outsized influence on climate resi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
