Biomes

Biomes are the composite of all species within a large scale ecological community. In the natural environment, these assemblies have typically co-evolved, so that they have a natural arrangement in terms of their positioning to compete for sunlight, water and nutrient resources; in some cases these associations are symbiotic, but in most cases they are simply optimal spatial arrangements to take advantage of all the resources available in a given habitat. For example, there is typically a vertical tiering, where plants of differing light requirements can occupy canopy, mid-level or forest floor niches; the same theory applies even in a grassland, where the canopy is simply the tallest of the grasses or herbs.

In the case of water competition, depth of rooting and tolerance to arid soils are chief determinants for spatial arrangement; as far as nutrient competition, plants will compete to determine the most robust competitor for a given edaphic niche. While the outcome geometry for the plant palette usually appears random, there is a complex network of ecological theory at work that determines the layout of the assembled community. The same concept applies to aquatic communities as to terrestrial systems, with some plants having immersed roots and others, either macrophytes or phytoplankton, floating or immersed at varying levels suitable for their sunlight needs.

  • Borneo montane rainforests Featured Article Borneo montane rainforests Borneo montane rainforests

    WWF Terrestrial Ecoregions Collection The Borneo montane rainforests can be likened to montane islands in a sea of lowland dipterocarp... More »

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    The ecogegions of Malaysia include a number of distinct types of rainforests, all of which are sustained by the plentiful rainfall of this equatorial region of Southeast Asia. In... 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 »

  • Declining grassland biodiversity Featured Article Declining grassland biodiversity Declining grassland biodiversity

    Declining grassland biodiversity is a major ecological issue, although it has received only a small fraction of the attention given to forests or wetlands, by... 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 »

  • Magellanic subpolar forests Featured Article Magellanic subpolar forests Magellanic subpolar forests

    WWF Terrestrial Ecoregions Collection The Magellanic subpolar forests is an ecoregion dominated by trees of the genus Nothofagus; this... More »

  • Namibian savanna woodlands Featured Article Namibian savanna woodlands Namibian savanna woodlands

    WWF Terrestrial Ecoregions Collection The Namibian Savanna Woodlands ecoregion covers the Great Escarpment that delimits the interior of... More »

  • Belizean pine forests Featured Article Belizean pine forests Belizean pine forests

    WWF Terrestrial Ecoregions Collection The Belizean pine forests on Central America's northwestern Caribbean Sea coast represent various... More »

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Registan-North Pakistan sandy desert Last Updated on 2014-06-28 00:07:20 The Registan-North Pakistan sandy desert is an ecoregion spanning southern Afghanistan; the extreme eastern portion of Iran; part of northwest Pakistan, covering a total land area of approximately 107,100 square miles. This ecoregion is classifed within the Deserts and Xeric Shrublands biome. There is considerable vertebrate species richness within the Registan-North Pakistan sandy desert, although endemism among this group is only represented by five reptilian taxa. Situated in the southernmost portion fo Afghanistan, the far east of Iran and along part of the northwest Pakistan border area, this ecoregion is an arid element of the palearctic landscape. The Khash Desert is a major feature ot the ecoregion. The Registan-North Pakistan sandy desert includes: Zohary’s Iranian steppes of Artemisietea herbae-albae iranica east of the Kuh-e Gamsidzai and the Kuh-e Palangan;... More »
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