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 »

  • Ecoregions of Malaysia Featured Article Ecoregions of Malaysia Ecoregions of Malaysia

    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 »

Recently Updated
Madagascar mangroves Last Updated on 2015-05-25 20:41:30 WWF Terrestrial Ecoregions Collection Shielded from monsoon winds by the Central Highlands of Madagascar, Madagascar mangroves occupy a wide range of environmental and climatic conditions, and chiefly occur at the western coastline along the Mozambique Channel of the Indian Ocean. Although the ecoregion’s species richness is low, it is noteworthy in supporting certain endemic tree species; for example, thre are only 163 vertebrate taxa found in the entire ecoregion. The Madagascar mangroves are within the Mangroves biome of the Afrotropic Realm. These mangroves also shelter highly diverse mollusk and crustacean communities, while capturing sediment that threatens coral reefs and seagrass beds. Dugongs, birds and sea turtles utilise mangroves, as do the native Malagasy people. Rice farming, shrimp aquaculture as well as stockpiling of... More »
Madagascar dry deciduous forests Last Updated on 2015-05-23 12:05:23 WWF Terrestrial Ecoregions Collection The Madagascar dry deciduous forests of western Madagascar are some of the world’s most species rich and most distinctive tropical dry forests. They are characterized by very high local plant and animal endemism at the species, genera and family levels. A significant portion of these forests have already been cleared, and the remaining forests are fragmented and critically threatened by uncontrolled burning and clearing for grazing and agriculture. Since human settlement of this region during the Holocene, an estimated 97 percent of the island’s dry deciduous western forests have been destroyed, and those remaining are extremely localized and fragmented. This ecoregion also contains spectacular limestone karst formations, known as tsingy, and their associated forests, including the World Heritage Site... More »
Zambezian Baikiaea woodlands Last Updated on 2015-05-16 21:25:29 WWF Terrestrial Ecoregions Collection The Zambezian Baikiaea woodlands lie along a zone where deep Kalahari sands occur in a wide belt along the Angolan-Namibian border across to Zimbabwe, supporting dry deciduous forest dominated by Baikiaea plurijuga. The hot, semi-arid climate and nutrient-poor soils mean that this region is not suitable for farming, and thus it has retained some of its natural vegetation. Over 160 mammal species are found here, including ungulates and large predators. However, human settlements occur along the Kunene, Kwando and Zambezi rivers, and the valuable Baikiaea plurijuga is sought after for the timber trade. The instability promoted in Angola by Soviet financed Cuban troops, and hostilities between Angola and Namibia in the Caprivi Strip have contributed to the degradation of this ecoregion. This ecoregion is a... More »
Zambezian halophytics Last Updated on 2015-05-15 15:26:27 WWF Terrestrial Ecoregions Collection The Zambezian halophytics ecoregion includes two spatially disjunctive units in Southern Africa: The Makgadikgadi Pan complex in Botswana and a smaller hypersaline unit in southern inland Mozambique. One of the largest saltpans in the world, the Makgadikgadi Pan complex in Botswana stretches out over 12,000 square kilometres. The ecoregion is classified within the Flooded Grasslands and Savanna biome. Surrounded by the semi-arid Kalahari savannas, the pans experience a harsh climate, hot with little rain, and are normally a vast, glaring expanse of salt-saturated clay. These pans are sustained by freshwater from the Nata River, and more infrequently, from input from the Okavango Alluvial Fan by way of the Boteti River. Saline- and drought-tolerant plant species generally line the pan perimeters, with grasslands... More »
Kalahari acacia-baikiaea woodlands Last Updated on 2015-05-11 18:02:12 WWF Terrestrial Ecoregions Collection Semi-arid Kalahari acacia-baikiaea woodlands stretches across the center of southern Africa, from northern Namibia through Botswana and slightly into the Tuli Block of South Africa. Surface water is scarce, and droughts occur approximately once every seven years. Therefore, the human population is relatively low, particularly on the sandveld that covers most of the ecoregion. This Kalahari woodland supports a rich and diverse fauna, including a variety of ungulates and a number of threatened large mammalian taxa such as White Rhinoceros (Ceratotherium simum), Black Rhinoceros (Diceros bicornis), Painted Hunting Dog (Lycaon pictus), and African Elephant (Loxodonta africana). However, human populations are increasing, and the burgeoning cattle industry has far-reaching adverse effects on the natural environment and... More »