Question

How do biomes differ?

Answer 1

The biome concept was introduced by Clements and Shelford. A distinct ecological community of plants and animals living together in a particular climate is called a biome. It is a level of organization between the landscape and biosphere. It is the largest geographical biotic unit, and is named after the dominant type of life form, such as tropical rain forest and grassland.

Complete answer:
Biomes are classified into aquatic and terrestrial biomes. Some of the major terrestrial biomes in the world are tropical rainforests, deserts, tropical grasslands (savannas), temperate grasslands, temperate deciduous forests, Mediterranean scrub, coniferous forests, chaparral and tundra.

1)Tundra biome: Tundra is a polar desert, with very low temperature and low precipitation. There are two main types of tundra, arctic tundra and alpine tundra. The alpine tundra is found high on the mountains. Tundra biome is characterized by a short growing season, low precipitation and permanently frozen deeper soil. Plant life consists of grasses, sedges and lichen (Reindeer moss). Trees are absent.

2)Desert biome: Deserts have annual precipitation less than 30cm. There is a lot of variability in desert types, with hot desert, cold deserts, high elevation deserts and rain shadow deserts. Most deserts are very hot. The hot deserts generally experience hot days and cold nights. Three types of plant forms are adapted to deserts – ephemeral, succulent and non-succulent.

3)Tropical grasslands (or Savanna biome): Savanna is grassland with scattered individual trees. Climate is the most important factor in creating a savanna. Savannas which result from climatic conditions are called climatic savannas. Savannas are always found in warm or hot climates where the annual rainfall is between 30-50 cm per year. Three major selective forces dominate the evolution of plant traits in savannas- recurring fire, periodic drought, and grazing. There are frequent fires in the savanna and dominant vegetation is fire adapted.

4)Temperate grasslands: Temperate grasslands are characterized as having grasses as the dominant vegetation. Trees and large shrubs are absent. Temperate grasslands have hot summers and cold winters and the amount of rainfall is less than in savannas. The type of grassland community that develops, and the productivity of grasslands, depends strongly upon precipitation. Higher precipitation leads to tall grasses with a high biodiversity of grasses.

5)Tropical rainforest: Tropical forests occur at low altitude zones near equator and characterized by a high temperature, high rainfall and greatest diversity of species. Soil is nutrient poor and acidic. Decomposition is rapid and soils are subject to heavy leaching. The dominant plants are phanerophytes – trees, lianas, and epiphytes.

6)Taiga biome: Winter is long and very cold and summer is short and cool. Precipitation occurs mainly in the form of snow, 40-100 cm annually. Soil is thin, nutrient poor and acidic. The flora consists mostly of cold-tolerant evergreen conifers with needle-like leaves such as pine, fir and spruce. Taiga is the largest terrestrial biome on Earth.
Temperate deciduous forest biome: A temperate deciduous forest consists of trees that lose their leaves every year. Temperate climate has four seasons of winter, spring, summer and fall. Precipitation is distributed evenly throughout the year. Soil is fertile, enriched with decaying litter.

7)Chaparral Biome: Chaparral biome is a shrubland biome of dense, spiny evergreen shrubs found at mid-latitudes along coasts where cold ocean currents circulate offshore. Chaparral biome is characterized by mild, rainy winters and long, hot, dry summers. Annual precipitation generally falls within the range of 30-50 cm.

Note: A biome is composed not only of the climax vegetation, but also of associated successional communities, persistent subclimax communities, fauna and soil. Thus, the biome concept embraces the idea of community, of interaction among vegetation, animal populations, and soil. It may be defined as a major region of distinctive plant and animal groups well adapted to the physical environment of its distribution area.