Biodiversity (main)

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Biodiversity

Biodiversity is the variation in living organisms, viewed within a given habitat, ecosystem or in the world as a whole. The concept is usually applied to the species diversity, although the notion of genetic biodiversity is applied to the variation in genes within an individual species. While most people think of rainforests as loci of great biodiversity, biomes such as oceans and grasslands are the likely repositories for even greater variation. Retention of diverse biota is important, since intact ecosystems are thought to be essential for provision of ecosystem services to humans, including maintenance of a diverse foodbank, pollination, clean water, flood control, pest control, waste decomposition, biomass energy resources and climate stability. Biodiversity is presently critical since we live in the era of the Mass Holocene Extinction, a period of species loss caused by man, and unrivaled in rate of species loss. Although the number of total species numbers in the tens of millions, most have not yet even been described. The extinction of a species is almost always related to destruction of habitat or man-made pollution.

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Coral reefs (collection) Coral reefs are one of the most diverse, complex, aesthetically appealing and threatened ecosystems on earth. This collection will include information on a wide range of topics... More »


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Crustacea (Biodiversity) Crustaceans are invertebrates belonging to the phylum Arthropoda and include such familiar groups as barnacles, crabs, crayfish, lobster, water fleas and pill bugs. Crustaceans... More »


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Ecoregions of Utah (EPA) The Ecoregions of Utah comprise a diverse set of plant communities and geomorphic provinces. Ecoregions denote areas of general similarity in ecosystems and in the type,... More »


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Habitat fragmentation (Biodiversity) Habitat fragmentation involves alteration of habitat resulting in spatial separation of habitat units from a previous state of greater... More »


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Virus (Biodiversity) A virus is a microscopic organism that can replicate only inside the cells of a host organism. Most viruses are so tiny they are only observable with at least a conventional... More »


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South China Sea The South China Sea is a critical world trade route and a potential source of... More »


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Devonian (Biodiversity) The Devonian period is a geologic time interval within the Paleozoic Era spanning from the end of the Silurian Period, aapproximately 417 million years before present (BP), to... More »


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Spinner dolphin (Biodiversity) The Spinner dolphin (Stenella longirostris), a marine mammal in the family of oceanic dolphins, gets itsname from the spinning behavior it shows when it leaps out of... More »


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Permian (Biodiversity) The Permian period lasted from 290 to 248 million years ago and was the last period of the Paleozoic Era. The distinction between the Paleozoic and the Mesozoic is made at the... More »


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Enriquillo wetlands (Biodiversity) Consisting of a series of lagoons, the Enriquillo wetlands ecoregion represents the remains of an ancient marine channel that divided the island of Hispaniola (Dominican Republic and Haiti) into two paleo-islands more than 5000 years before present. The largest lake in this ecoregion, Lake Enriquillo in the Dominican Republic is the largest and most hypersaline lake in all of the Antilles. It consists of a depression that is approximately 44 metres (m) below sea level, surrounded by thorny subtropical mountains and dry forests of great biological importance. The lake surface is the lowest topographic point in the entire Caribbean Basin. This lake is home to the largest population of American crocodile (Crocodylus acutus), although currently its the populations of this reptile are at risk. It is also the... More »


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Nama Karoo (Biodiversity)</span> The Nama Karoo is a vast, open, arid ecoregion in southern Africa dominated by low-shrub vegetation, punctuated by rugged relief. Although not remarkably rich in species or endemism, the flora and fauna of the region are impressively adapted to its climatic extremes. The Nama Karoo ecoregion is part of the Deserts and Xeric Shrublands biome, within the Afrotropics Realm. The major threats to biodiversity are posed by pastoralism, introduction of alien species of plants, mining and conversion of native habitat to agriculture, all exacerbated by the fact that less than one percent of the ecoregion is presently conserved. Most of the Nama Karoo occurs on the central plateau of the Cape Province in South Africa, although it extends over the Orange River into Namibia in the northwest. The Great Escarpment,... More »


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Namibian savanna woodlands The Namibian savanna woodlands ecoregion covers the Great Escarpment that delimits the interior of southern Africa from both the Kaokoveld Desert and Namib Desert. This broken and deeply dissected escarpment is an area of high endemism for plants, invertebrates, amphibians, reptiles, mammals and birds. The northern area of the ecoregion, the Kaoko escarpment, is an endemism "hotspot" (area of extremely high species richness and endemism). The Namibian savanna woodlands comprise a land area of approximately 87,100 square miles. This northern area is poorly protected and is under threat from poaching, off-road driving, and to a lesser extent from farming, and resultant habitat fragmentation; much of this destabilisation in the Angolan portion of the ecoregion stems from the Cuban mercenaries aided... More »


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Colorado Plateau shrublands The Colorado Plateau shrublands is epitomized by the Grand Canyon, an area that has been called the "land of color and canyons." The Plateau can be thought of as an elevated, northward-tilted saucer. It is characterized by its high elevation and arid to semi-arid climate. The Colorado Plateau has developed extensive topographic relief through the erosive action of high-gradient, swift-flowing rivers that have downcut and incised the plateau. Approximately 90 percent of the plateau is drained by the Colorado River and its tributaries, notably the lower catchmentCatchment is the entire area of a hydrological drainage basin. of the Green River, the San Juan River and Animas River. This ecoregion is classified within the Deserts and Xeric Shrublands biome, and is codified as WWF Ecoregion... More »


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Kaokoveld Desert (Biodiversity) The Kaokoveld Desert represents the northern area of the vast Namib Desert. It is a harsh, arid landscape of rugged mountains, gravel plains and shifting sand dunes. Surface water is scarce, with only one perennial river flowing through the region, the Kunene River. However, the dry riverbeds transecting the area are the lifelines of the desert. They are well vegetated and are home to large mammals such as African Elephant, Black Rhino and Giraffe. The remainder of the landscape is poorly vegetated and extremely arid. Coastal fogs allow a range of interesting, desert-adapted animal species to survive in this low-rainfall environment. The relict gymnosperm Welwitschia mirabilis, which represents the sole surviving member of its family, is found throughout the ecoregion. The Kaokoveld Desert is well protected in... More »