Biogeography

Biogeography is the study of the distribution of biological organisms. The scale of analysis ranges from very small micro-topography regimes to continental dimensions. Fundamental concepts in this field of study are the nature of barrier formation and response of species to their patterns of travel and migration; in particular, the presence of rivers, mountain ranges, deserts and other natural boundaries are examples of large scale barriers. Besides such major landform barriers there are soil, topographic and meteorological factors that influence the distribution of each species. In the case of smaller scale regimes that are applicable for some bacteria or limited range plant species, there are often very restricted niches; for example, certain bacteria extremophiles may be limited to such localized features as small geyser pools, and some rare plants may have a single extant colony defined specialized soils such as serpentine and narrow climatic zone. Inherent in the concept of biogeography are the processes of speciation, extinction, dispersal and migration.   

  • Douglas-fir Featured Article Douglas-fir Douglas-fir

    The Douglas-fir (scientific name: Pseudotsuga) is a genus of tree that includes ar least five species found in North America and Asia: Scientific... More »

  • Ocean acidification troubles Featured Article Ocean acidification troubles Ocean acidification troubles

    The seas in which corals and other calcifying species dwell are turning acidic, their pH slowly dropping as Earth's oceans acidify in response to increased carbon dioxide... More »

  • Big Bend National Park, United States Featured Article Big Bend National Park, United States Big Bend National Park, United States

    Big Bend National Park is one of the two National Parks located in the state of Texas, in the USA. Big Bend National Park is located in the Big Bend region along the border of... More »

  • Great Victoria Desert Featured Article Great Victoria Desert Great Victoria Desert

    WWF Terrestrial Ecoregions Collection A vast, sparsely populated region covered by dunefields and gibber plains, the Great Victoria Desert... More »

  • Daugava River Featured Article Daugava River Daugava River

    The Daugava River drains portions of the countries of Latvia, Belarus, Estonia and Russia, prior to discharging to the Gulf of Riga. Also known as the West Dvina River, this... More »

  • Mojave Desert Featured Article Mojave Desert Mojave Desert

    WWF Terrestrial Ecoregions Collection The Mojave Desert is the smallest of the four North American deserts. While the Mojave lies between the... More »

  • Cactus Featured Article Cactus Cactus

    Cactus is a family of plants that are specially adapted to survive arid conditions, most often having leaves reduced to spines, and succulent characteristics. The scientific... More »

  • Spinner dolphin Featured Article Spinner dolphin Spinner dolphin

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

  • Ecoregions of Chile Featured Article Ecoregions of Chile Ecoregions of Chile

    Chile has eight ecoregions that occur entirely or partly within its borders on the mainland and three ecorgions offshore: Sechura desert Atacama... More »

Recently Updated
Sundarbans, Bangladesh Last Updated on 2014-10-19 18:16:11 The Sundarbans (21°30'- 22°30'N, 89°12'-90°18'E) are a World Heritage Site which consists of three wildlife sanctuaries (Sundarbans West, East and South) lying on disjunct deltaic islands in the Sundarbans Forest Division of Khulna District, close to the border with India and immediately west of the principal outflow of the Ganges, Brahmaputra and Meghna rivers. The Sundarbans belong to Bengalian Rainforest biogeographical province. 1977: All three wildlife sanctuaries established under the Bangladesh Wildlife (Preservation) (Amendment) Act, 1974, 1878: The three sanctuaries gazetted as forest reserves. 1996: The total area of wildlife sanctuaries extended; the entire Sundarbans is reserved forest, established under the Indian Forest Act, 1878. 1997: The Sundarbans inscribed on the World Heritage List. The total area of the Bangladesh... More »
Ecoregions of Bangladesh Last Updated on 2014-10-19 17:45:45 Bangladesh has five ecoregions: Sundarbans mangroves Sundarbans freshwater swamp forests Lower Gangetic Plains moist deciduous forests Mizoram-Manipur-Kachin rain forests Myanmar coastal rain forests The ecoregion lies in the vast delta formed by the confluence of the Ganges, Brahmaputra, and Meghna rivers. The maze of mangrove channels extends across southern Bangladesh and India's West Bengal State.The Sundarbans Mangroves ecoregion is the world's largest mangrove ecosystem. Named after the dominant mangrove species Heritiera fomes, locally known as sundri, this is the only mangrove ecoregion that harbors the Indo-Pacific region's largest predator, the tiger (Panthera tigris). Unlike in other habitats, here tigers live and swim among the mangrove islands, where they hunt scarce prey such as chital deer (Cervus axis), barking deer (Muntiacus muntjak), wild... More »
Mangrove ecology Last Updated on 2014-10-19 17:31:46 ​Mangrove ecology is the study of biotic interactions within mangrove swamp ecosystems. These habitats are significant not only for the biodiversity they represent, but also for the protection of coastal erosion, and for the provision of protected nursery areas for marine fauna.   Mangroves worldwide cover an approximate area of 240 000 square kilometers of sheltered coastlines in the tropics and subtropics. Mangroves stabilize coastal intertidal soils pereventing coastal erosion Four of the most common ecotypes include fringe, riverine, basin, and scrub forests. Mangroves are restricted to the intertidal zone. Mangroves in general have a great capacity to recover from major natural disturbances. Mangroves maintain water quality by trapping sediments and taking up excess... More »
Big Bend National Park, United States Last Updated on 2014-10-19 16:55:59 Big Bend National Park is one of the two National Parks located in the state of Texas, in the USA. Big Bend National Park is located in the Big Bend region along the border of Texas and Mexico where the Rio Grande bends toward the Gulf of Mexico. Because the park contains a variety of habitat types including mountains, deserts, and riparian habitats, the park is home to a diverse flora and fauna. Visitors arrive at Big Bend National Park to hike, camp, watch wildlife, and experience the river by rafting or canoeing. Big Bend National Park is located in the big bend of the Rio Grande along more than 161 kilomters (100 miles) of the Texas-Chihuahua-Coahuila border southeast of El Paso, Texas in Brewster County, Texas. It includes a large portion of the Chihuahuan Desert as well as the Chisos Mountains on the Texas side of the Rio Grande’s expansive steep canyons. In 1933,... More »
Habitat fragmentation Last Updated on 2014-09-30 10:21:30 Habitat fragmentation involves alteration of habitat resulting in spatial separation of habitat units from a previous state of greater continuity. Figure 1. Aerial photograph of dry forest scrub in southern Zambia, fragmented by agricultural land conversion. 2008 This phenomenon occurs naturally on a geologic time-scale or in unusual and catastrophic events: however, since the Holocene era, humans have produced dramatic and swift transformation of landscapes throughout the world, resulting in a level of habitat fragmentation that has induced worldwide reduction in biodiversity and interuption of  sustainable yields of natural resources. Humans produce habitat fragmentation chiefly from agricultural land conversion, urbanization, pollution, deforestation and introduction of alien species; ironically, both human caused wildfires as well as the... More »