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Tundra has vegetation formed mainly by mosses and lichens. In the fauna the densely furred animals, like caribous, musk oxen and polar bears, and also migratory birds are found.

The major terrestrial biomes are: tundra, taigas (or boreal forest), temperate forests, tropical forests, grasslands and deserts. 

Tropical rain forests, like the Amazon forest and the Congo forest, are typically located in low latitude, i.e., in the equatorial and tropical zones.

A biome is a prevailing ecosystem constituted by similar biotic and abiotic factors present in one or more regions of the planet.

In tropical forests tall trees of several species have their crowns forming a superior layer under which diverse other trees and plants develop forming other inferior layers. From the upper layer to the inferior layers the penetration of light lowers gradually and the exposition to wind and rain, the moisture and the temperature also vary. Different compositions of abiotic factors condition the prevailing of different vegetation in each layer. 

The biodiversity of these ecosystems can be explained by the great availability of the main abiotic factors for photosynthesis. Since these factors are abundant plants can perform maximum photosynthetic activity, living and reproducing easily. With a great amount and diversity of producers (autotrophs), the consumers (heterotrophic animals and microorganisms) also have abundant food and a complex food web emerges creating many different ecological niches to be explored. So the appearance of varied living beings as well as the existence of large populations is possible.

In the vegetation of the tropical forests broadleaf evergreen trees predominate. On the top of the trees epiphytes and lianas grow. Many varieties of pteridophytes can be found in these forests. Regarding the fauna, the abundance and diversity is also great: there are monkeys, rodents, bats, insectivores, felines, reptiles, birds, amphibians and invertebrates, mainly insects.

In the temperate forest deciduous trees predominate. Mammals are found in great number, like bears and deer.

Taiga, or the boreal forest, is characterized by coniferous trees, pine forests. There are also mosses, lichens, small bushes and angiosperms. In the taiga many mammals, like moose, wolves, foxes and rodents, migratory birds and a great diversity of insects are found.

Amphibians are terrestrial vertebrates extremely rare in desert environments (although there are a few species adapted to this type of ecosystem). Amphibians are rare in deserts because  so they easily lose water by evaporation and desiccate. They also need an aquatic environment to reproduce, since their fecundation is external and their larva is water-dependent.

The predominant fauna of desert ecosystems is formed by reptiles, like lizards and snakes, terrestrial arthropods and small rodents. In these areas plants very adapted to a dry climate may be found, like the cactus, which are plants that do not have real leaves and thus lose less water, along with grasses and bushes near places where water is available. 

Grasslands may be classified into steppes and savannahs. In the steppes the prevailing vegetation is grass, as in the pampas of South America and in the prairies of North America. The fauna is mainly formed by herbivores, like rodents and ungulates. The savannahs present small trees, for example in the Brazilian cerrado or the African savannahs. The fauna is diverse; in the Brazilian cerrado there are animals like ostriches, lizards, armadillos, jaguars, etc., and many types of insects; the African savannahs are the home of large herbivores and carnivores, like zebras, giraffes, antelopes, lions and leopards.

The steppe grasslands of North America are called prairies. The grasslands of South America are known as “pampas” (the steppe grassland) and “cerrado” (the savannah grassland).

Deciduous trees are plants that lose their leaves in a period of the year. In the case of the deciduous trees of the temperate forest the fall of the leaves occurs in the autumn (fall). The loss of leaves is a preparation to face the cold months of the winter: roots, stem and branches are more resistant to low temperature and snow than the leaves; without leaves the metabolic rate of the plant is reduced; the decaying fallen leaves help to nourish the soil.