The terrestrial part of the biosphere is divisible into enormous regions called biomes, which are characterized, by climate, vegetation, animal life and general soil type.
No two biomes are alike.
The most important climatic factors are temperature and precipitation.
- Tundra- Northern most region adjoining the ice bound poles. Devoid of trees except stunted shrubs in the southern part of tundra biome, ground flora includes lichen, mosses and sedges.
The typical animals are reindeer, arctic fox polar bear, snowy owl, lemming, arctic hare, ptarmigan. Reptiles and amphibians are almost absent
- Taiga- Northern Europe, Asia and North America. Moderate temperature than tundra. Also known as boreal forest.
The dominating vegetation is coniferous evergreen mostly spruce, with some pine and firs. The fauna consists of small seed eating birds, hawks, fur bearing carnivores, little mink, elks, puma, Siberian tiger, wolverine, wolves etc.
- Temperate Deciduous Forest- Extends over Central and Southern Europe, Eastern North America, Western China, Japan, New Zealand etc.
Moderate average temperature and abundant rainfall. These are generally the most productive agricultural areas of the earth The flora includes trees like beech, oak, maple and cherry. Most animals are the familiar vertebrates and invertebrates.
- Tropical rain forest- Tropical areas in the equatorial regions, which is a bound with life. Temperature and rainfall high.
Tropical rainforest covers about 7% of the earth’s surface & 40% of the world’s plant and animal species.
Multiple storey of broad-leafed evergreen tree species are in abundance.
Most animals and epiphytic plants(An epiphyte is a plant that grows harmlessly upon another plant) are concentrated in the canopy or tree top zones
- Savannah- Tropical region: Savannah is most extensive in Africa
Grasses with scattered trees and fire resisting thorny shrubs.
The fauna include a great diversity of grazers and browsers such as antelopes, buffaloes, zebras, elephants and rhinoceros; the carnivores include lion, cheetah, hyena; and mongoose, and many rodents
- Grassland- North America, Ukraine, etc . Dominated by grasses. Temperate conditions with rather low rainfall. Grasses dominate the vegetation. The fauna include large herbivores like bison, antelope, cattle, rodents, prairie dog, wolves, and a rich and diverse array of ground nesting bird
- Desert- Continental interiors with very low and sporadic rainfall with low humidity. The days are very hot but nights are cold. The flora is drought resistance vegetation such as cactus, euphorbias, sagebrush. Fauna : Reptiles, Mammals and birds.