World Biomes, Natural Vegetation, Deserts, Grasslands and Forests Notes for UPSC: Tropical Rainforest to Tundra with Regions, Local Names, Environmental Issues and Mains Angle

A biome is a large natural region with a particular type of climate, soil, plants and animals. The world's natural vegetation, from the dense Amazon rainforest to the frozen tundra and from the African savanna to the Sahara desert, follows the pattern of temperature and rainfall. For UPSC, questions come as "Which grassland is found in Argentina?", "Which is the driest desert?" and "Match the biome with the region", and the Mains asks about deforestation, desertification and the role of forests in the climate. These notes cover every major biome of the world in clear tables, the names of the world's deserts and grasslands, the altitude-based vegetation, and the environmental issues attached to them.

Why Learn World Biomes?

The biomes are the base of both physical geography and environment and ecology. They explain why people live where they do, which crops grow where, and why some regions are fragile. They also help in the map-based questions on the Prelims. Link this note with our notes on the Climatic Regions of the World and Natural Vegetation and Forests of India of India for a complete view.

Major Biomes at a Glance

World Grasslands and Their Local Names

Major Deserts of the World

Altitude Zones and the Mountain Vegetation

As you go up a mountain, the temperature falls by about 6.5 degrees Celsius per 1,000 metres, and the vegetation changes like the change from the equator to the poles. In the Himalaya, you pass from the tropical forests at the foot to the temperate forests of oak and chestnut at about 1,500 to 2,500 metres, the coniferous forests of pine, fir and spruce at 2,500 to 3,500 metres, the alpine meadows (bugyals) and the shrubs above that, and finally the snow-covered peaks at about 4,500 metres and above. This is called the altitudinal zonation. The tree line (the limit beyond which trees do not grow) falls lower in the higher latitudes.

Importance of Forests and the Environmental Issues

• Tropical rainforests are called the "lungs of the earth" for oxygen and carbon storage, and house more than half of the world's species. The Amazon faces deforestation for cattle, soy and logging, and some parts are shifting from carbon sinks to the sources of carbon.
• Boreal forests store a huge amount of carbon and are threatened by the forest fires and the thawing of the permafrost, which releases methane.
• Grasslands have been converted into farms in many parts of the world, causing soil erosion, as in the Dust Bowl of the 1930s in the USA.
• Deserts are expanding in some regions because of overgrazing, deforestation and climate change, which is called desertification. The UNCCD (1994) is the global treaty, and the World Day to Combat Desertification is on 17 June. Africa's Great Green Wall in the Sahel is an effort to restore the land across the continent.
• Tundra is highly sensitive to warming, because the permafrost thaw damages the buildings and releases the greenhouse gases.

Hardwood and Softwood Forests

For the economic geography, it is helpful to know the difference between the two types of timber forests. Hardwood comes from the broad-leaved trees of the tropical and temperate regions, such as teak, mahogany, ebony, sal, oak and rosewood. It is strong and costly, and is used for furniture and construction. The trees are mixed, which makes the logging difficult. Softwood comes from the coniferous trees such as pine, fir, spruce and cedar of the taiga. The trees grow in pure stands, and the logging is easier, which is why the taiga supports the large paper, pulp and matchstick industries in Canada, Russia and Scandinavia. A question often asks which region produces which kind of wood, so it is worth remembering.

How People Live in Each Biome

Human life adapts to each biome. In the equatorial rainforests, tribes such as the Pygmies of the Congo and the Amazonian tribes practise hunting, gathering and shifting cultivation. In the savannas, the Masai herd cattle. In the hot deserts, the Bedouins and the Tuareg are the nomads, and the oases support the date farming. In the Mediterranean region, the farmers grow fruit and wine grapes. In the temperate grasslands, large mechanised farms produce wheat, and in the taiga, logging and mining are the main activities. In the tundra, the Inuit and the Sami live by hunting, fishing and reindeer herding. Today, many of these communities face threats from the loss of land, the climate change and the pressure of the modern economy, which is a good point to add to the Mains answers on tribal and indigenous people.

The Mains Angle

For the GS I answers, link the biome with the human life: the rainforest tribes, the pastoralists of the savanna and the steppes, the oasis farming in the deserts, and the Arctic communities. Explain how modern economic activities, such as mining, plantation and agribusiness, have changed these areas. The common causes of the biome loss are the population pressure, the agricultural expansion, the timber demand, the mining and the climate change, and the solutions include the sustainable forest management, the protected areas, the community participation, the reforestation and the international agreements such as the UNCCD and the Convention on Biological Diversity. Add one or two recent examples from the news.

Memory Tips and Previous-Year Style Practice

• Grasslands: "Prairies - North America, Pampas - Argentina, Steppes - Eurasia, Veld - South Africa, Downs - Australia".
• The Sahara is the largest hot desert, the Antarctic is the largest desert overall, and the Atacama is the driest.
• Which biome is the "orchard of the world"? Answer: The Mediterranean region.
• Which type of the forest has the maximum biodiversity? Answer: The tropical rainforest.
• Which South American grassland is found in Argentina? Answer: The Pampas.

Frequently Asked Questions (FAQ)

What is a biome?

A biome is a large natural region with a particular climate, soil, plants and animals.

Which is the largest hot desert in the world?

The Sahara in North Africa.

Which is the driest desert in the world?

The Atacama desert in Chile and Peru.

What is the largest desert in the world by area?

Antarctica, which is a cold desert.

Which grassland is found in Argentina?

The Pampas.

Which grassland is found in North America?

The Prairies.

What are the steppes?

The temperate grasslands of Eurasia, from Ukraine to Mongolia.

Which region is called the orchard of the world?

The Mediterranean region, for its citrus fruits, grapes and olives.

What is the taiga?

The belt of the coniferous forests in the northern regions of Canada, Europe and Siberia.

What is permafrost?

The permanently frozen ground, found in the tundra and the cold regions.

Which international treaty deals with desertification?

The UNCCD, adopted in 1994.

How are biomes asked in the Prelims?

As match-the-following questions on the biome, the region and the local names of grasslands and deserts.