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ⓘ Ecozone. An ecozone or biogeographic realm is the largest scale biogeographic division of the earths surface. These divisions are based on the historic and evol ..




Ecozone
                                     

ⓘ Ecozone

An ecozone or biogeographic realm is the largest scale biogeographic division of the earths surface.

These divisions are based on the historic and evolutionary distribution of plants and animals. Ecozones represent large areas of the Earth surface where plants and animals developed in relative isolation over long periods of time, and are separated from one another by geologic features, such as oceans, broad deserts, or high mountain ranges, that formed barriers to plant and animal migration. Ecozones correspond to the floristic kingdoms of botany or zoogeographic regions of mammal zoology.

Ecozones are characterized by the evolutionary history of the plants and animals they contain. As such, they are distinct from biomes, also known as major habitat types, which are divisions of the earths surface based on life form, or the adaptation of plants and animals to climatic, soil, and other conditions. Biomes are characterized by similar climax vegetation, regardless of the evolutionary lineage of the specific plants and animals. Each ecozone may include a number of different biomes. A tropical forest in Central America, for example, may be similar to one in New Guinea in its vegetation type, but these forests are inhabited by plants and animals with very different evolutionary histories.

The patterns of plant and animal distribution in the worlds ecozones was shaped by the process of plate tectonics, which has redistributed the worlds land masses over geological history.

The term ecozone, as used here, is a fairly recent development, and other terms, including kingdom, realm, and region, are used by other authorities with the same meaning. J. Schultz uses the term "ecozone" to refer his classification system of biomes.

                                     

1. Biogeographical realms

In 1975 Miklos Udvardy proposed a system of 203 biogeographical provinces, which were grouped into eight biogeographical realms. Udvardys goal was to create an integrated ecological land classification system that could be used for conservation purposes.

                                     

2. WWF Ecozones

The WWF ecozones are based largely on the biogeographic realms of Pielou 1979 and Udvardy 1975. A team of biologists convened by the World Wide Fund for Nature WWF developed a system of eight biogeographic realms ecozones as part of their delineation of the worlds over 800 terrestrial ecoregions.

  • Indomalaya 7.5 mil. km² including the South Asian subcontinent and Southeast Asia
  • Oceania 1.0 mil. km² including Polynesia, Fiji and Micronesia
  • Palearctic 54.1 mil. km² including the bulk of Eurasia and North Africa
  • Nearctic 22.9 mil. km² including most of North America
  • Neotropic 19.0 mil. km² including South America and the Caribbean
  • Afrotropic 22.1 mil. km² including Sub-Saharan Africa
  • Australasia 7.7 mil. km². The northern boundary of this zone is known as the Wallace line.
  • Antarctic 0.3 mil. km² including Antarctica.

The WWF scheme is broadly similar to Udvardys system, the chief difference being the delineation of the Australasian ecozone relative to the Antarctic, Oceanic, and Indomalayan ecozones. In the WWF system, The Australasia ecozone includes Australia, Tasmania, the islands of Wallacea, New Guinea, the East Melanesian islands, New Caledonia, and New Zealand. Udvardys Australian realm includes only Australia and Tasmania; he places Wallacea in the Indomalayan Realm, New Guinea, New Caledonia, and East Melanesia in the Oceanian Realm, and New Zealand in the Antarctic Realm.

                                     
  • and neighbouring islands. The northern boundary is the Wallace Line. The ecozone includes Australia, the island of New Guinea including Papua New Guinea
  • Nearctic is one of the eight terrestrial ecozones dividing the Earth s land surface. In ecology, an ecozone is a large land mass that contains many terrestrial
  • Neotropic or Neotropical means one of the world s eight terrestrial ecozones This ecozone includes South and Central America, the Mexican lowlands, the Caribbean
  • The Afrotropic is one of the Earth s eight ecozones The zone was formerly known as the Ethiopian Zone. The zone includes Africa south of the Sahara, the
  • Palearctic or Palaearctic ecozone is one of the eight dividing the Earth s surface. The Palearctic is by far the largest ecozone It includes the terrestrial
  • The Holarctic ecozone refers to the habitats found throughout the northern continents of the world as a whole. This region is divided into the Palearctic
  • Gondwana. It is the geographical area which contains the Australasian ecozone Its islands are all south - east of the Bali Lombok line, known as the Wallace
  • moth of the family Sphingidae. It is found in Palearctic ecozone and sometimes the Nearctic ecozone This species has been found in Scotland but is usually
  • archipelago, Taiwan, and the Aleutian islands. On the other hand, the Oceania ecozone includes all of Micronesia, Fiji, and all of Polynesia except New Zealand