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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.

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Borneo peat swamp forests Last Updated on 2014-04-15 17:45:53 Although the Borneo peat swamp forests are not as biodiverse as neighbouring lowland rainforests, the Borneo Peat Swamp Forests are some of the most speciose peat swamp forests in Southeast Asia. Peat swamp forests are a key habitat for the unique endangered Borneo endemic proboscis monkey (Nasalis larvatus). They are also home to the world's most desirable aquarium fish, the arowana (Scleropages formosus). This ecoregion is made up of the peat swamp forests along the western coasts of the island of Borneo, within the Malaysian state of Sarawak and Indonesian Kalimantan. Most of the peat swamp forests are associated with coastal areas, but two large areas of peat swamp forests occur around Lake Mahakam and Lake Kapuas. Based on the Köppen climate zone system, this ecoregion falls in the tropical wet climate zone. The peat swamp forests of Borneo have vegetative and... More »
Borneo montane rainforests Last Updated on 2014-04-15 17:23:27 The Borneo montane rainforests can be likened to montane islands in a sea of lowland dipterocarp forests. This isolation has produced a unique and diverse set of montane species. Of Borneo's endemic bird species, twenty-three (73 percent) are montane. There are more than 150 mammal species in montane forests, making this ecoregion globally outstanding for mammal richness, and it is the most speciose montane rain forest found in the Indo-Pacific region. Despite this wealth of diversity, large tracts of Borneo's montane forests have not been explored to catalog the flora and fauna. This ecoregion represents the montane forests in the central region of the island of Borneo and falls within the boundaries of all three nations with territory in Borneo: Malaysia, Indonesia, and Brunei. Montane forests are much cooler and moister than lowland forests. For every 1000 meters (m)... More »
Borneo lowland rainforests Last Updated on 2014-04-15 16:43:28 Borneo lowland rainforests are the richest rainforests in the world and rival the biodiversity of New Guinea and the Amazon. With 267 Dipterocarpaceae species (155 endemic to Borneo), Borneo is the center of the world's diversity for dipterocarps. These forests are home to the world's smallest squirrel, the eleven centimetre long pygmy squirrel, and the endangered orangutan. In northeast Borneo, populations of Sumatran rhinoceros and Asia's largest terrestrial mammal, the Asian elephant, still tenuously survive in the last pockets of forest. These forests contain the parasitic plant Rafflesia arnoldii, which produces the world's largest flower (up to one meter in diameter). These forests are globally outstanding for both bird and plant richness, with more than 380 birds and an estimated 10,000 plant species found within its boundaries. Unfortunately, these forests have... More »
Madagascar mangroves Last Updated on 2014-04-15 15:37:23 Shielded from monsoon winds by the central mountains of Madagascar, Madagascar mangroves occupy a wide range of environmental and climatic conditions along the western coastline along the Indian Ocean. Although the ecoregion’s species richness is low, it is unusual in supporting certain endemic tree species. The mangroves also shelter highly diverse mollusk and crustacean communities, while capturing sediment that threatens coral reefs and seagrass beds. Birds, sea turtles, and dugongs all utilize mangroves, as do the Malagasy people. Rice farming, shrimp aquaculture and construction materials are all carried out within these mangroves. On Madagascar, mangroves are found primarily along the western coast. They occur in a wide range of environmental and climatic conditions, fostered by a low coastal platform, high tidal range, and a constant freshwater supply from numerous... More »
Kalahari xeric savanna Last Updated on 2014-04-15 13:18:17 The Kalahari xeric savanna is an ecoregion in southern Africa characterized by a harsh climate, where temperatures may increase by 45°C from night to day, and rainfall is infrequent. Rain falls only during the summer on the reddish-brown Kalahari sands , pelting the savanna with violent, localized storms. Although this area is semi-arid, there is an impressive diversity of migratory birds and large mammals, both herbivorous and carnivorous. A considerable amount (approximately 18 percent) of this ecoregion is protected. Where it is not protected, heavy grazing has degraded the habitat. Fences are a serious problem because they obstruct the migratory routes of ungulates, and they pose significant threats to biodiversity in unprotected areas. The Kalahari xeric savanna ecoregion stretches across northwestern South Africa, southern Botswana and southeastern Namibia. Most of it... More »