A biome is a geographical extensive ecosystem where all flora and fauna are found collectively. It is the total assemblage of plant and animal life interacting within the biosphere. Biomes are defined by abiotic factors like,relief, climate,soils and vegetation. They are classified into two broad categories,
- Terrestrial biomes
- aquatic biomes
Terrestrial biomes is a group of living organisms that live and interact with one another on land. They are mainly determined by temperature and rainfall. Some of the major terrestrial biomes of the world are
A. Tropical Forest Biomes
B. Tropical Savanna Biomes
C. Desert Biomes
D. Temperature Grassland
E. Tundra Biomes
A. Tropical Forest Biomes
The tropical forest biome is comprised of several sub-biomes, including evergreen rainforest, seasonal deciduous forest etc.
Tropical forest have the highest biodiversity and primary productivity of any of the terrestrial biomes. The Amazon basin, Congo basin and Indonesian islands are the major regions of this biome. These regions have very dense forests and so have great economic importance. Human settlements are found scattered here. They sustain their livelihood through food gathering, fishing, lumbering and shifting cultivation. Due to the humid nature of this biome, the people get afflicted to tropical diseases like malaria, yellow fever etc. The chief trees found here are rubber, bamboo, ebony,etc. Bats, pheasants, jaguars, elephants, monkeys etc. are the important birds and animals found here.
B. Tropical Savanna (Grasslands) Biomes
Tropical grasslands are generally found between tropical forests and deserts. Tropical Savanna biomes are found between 10° to 20°N and S latitudes. These grasslands are generally flat and are found in the Sahel, south of Sahara in East Africa and in Australia. This biome is generally hot and dry and experiences moderate to low rainfall. So, the grass which grow here are tall and sharp. Hence the chief occupation of the people found here is herding. The primitive people living here are nomadic. The common animals found here are the lion,leopard, tiger,deer, red oats grass, lemon grass etc. are found in this biome.
C. Desert Biomes
Deserts are usually found on the western margins of the continents between 20° and 30° N and S latitudes. The annual rainfall is less than 25cm in these regions. Due to the lack of rainfall and arid conditions, these regions do not possess any vegetaion but have special vegetaion type called Xerophytes. As the soil is sandy and saline, deserts remain agriculturally unproductive. Drought resistant throny scrubs and bushes, palms are found here.
Tribal people who live here practice food gathering and hurting. They move their temporary settlements frequently in search of pasters. Transportation becomes very difficult here and is carried on by camels. Reptiles like snakes, lizards, scorpions etc., are most commonly found here.
D. Temperate Grassland Biomes
Temperate Grasslands are usually found in the interior of the continents and are characterized by large seasonal temperature variations, with warm summer and cold winter. The type of grassland in these regions strongly depends upon precipitation. Higher precipitation leads to talk and short and soft grass. These regions favour wheat cultivation. Extensive mechanised agriculture is practised due to lack of farm labour. Pastrol industry becomes the main occupation, thereby facilitating slaughtering of animals, packing of raw and processed meat, dairy products etc. The common birds and animals are grass hopper, wolf, bison, prairie dog etc.
E. Tundra Biomes
These vast lowlands are found where the ground remains frozen. Greenland, Arctic and Antarctic regions and Northern parts of Asia, Canada and Europe fall in this biome. These regions are also called Barren lands. This biome experiences long severe winter and short cool summer. Due to the prevailing of low temperature and short growing seasons, the net primary productivity is very low in tundra. People are nomadic. Hunting and fishing are their major occupations. The population here is extremely sparse and the harsh environment makes them change their settlement frequently. They live in igloos in winter and in tents during summer. Arctic moss, Arctic willow, lichens etc. grow here. Fauna like the polar bear, wolverine, reindeer, snowly owl are found here.
Aquatic biome is a group of living organisms that live and interact with one another and its aquatic environment for nutrients and shelter. Like terrestrial biomes, aquatic biomes are influenced by a series of abiotic factors.
- Fresh water biomes
- Marine biomes
A. Fresh water Biomes:
It comprises lakes, ponds, rivers, streams, wetlands etc. It is influenced by various abiotic components such as the volume of water, water flow, composition of oxygen, temperature,etc. Humans rely on freshwater biomes for drinking water, crop irrigation, sanitation and industry. Water lily,lotus, duck weeds etc. are the common plants found here. Trout, salmon,turtles, crocodiles etc. are the animals found here.
B. Marine Biomes:
They are the largest aquatic biomes on earth. They are continuous bodies of salt water and provide a wide range of habitats for marine plants and animals. Coral reefs are a second kind of marine biomes within the ocean.Estuaries, coastal areas where salt water and fresh water mix, form a third unique marine biome. As water provides maximum mobility to marine organisms, nutrients are circulated more quickly and efficiently here than the terrestrial biomes. Apart from animals, plants such as kelp, algae, phytoplankton etc. also grow in water. Aquatic biomes are not only important for plants and animals, but also for humans. Humans use aquatic biomes for water, food and leisure activities. Some of the threats and issues to aquatic biomes are overfishing. Pollution and rise in sea level.
The biosphere extends from the deep ocean trenches to lush rain forests. People play an important role in maintaining the flow of energy in the biosphere. At the same time, the primary cause of today’s loss of biodiversity is habitat alteration caused by human activities. The ever increasing population results in over exploitation of biological resources. This has an adverse impact on flora and fauna on earth. There are places on earth that are both biologically rich and deeply threatened. Hence it is man’s duty to conserve and care for the earth and make it a better place to live in.