Life on Earth

Biomes of the world, biodiversity hotspots, ecotourism, GI tags, forest rights and India’s traditional water tanks.

Key ideas

• A biome is a large region with a similar climate, plants and animals, decided by temperature, rainfall and vegetation.
• The land biomes are forest, grassland, desert and tundra; water biomes cover about three-fourths of the Earth.
• Tropical rainforests lie between 23.5° N and 23.5° S and are hot and wet all year; the taiga is a belt of conifers; the tundra has permafrost.
• Temperate grasslands such as prairies and steppes have cold winters; tropical savannas in Africa are warm, with scattered trees.
• In a food pyramid, numbers, biomass and energy fall at each level, because energy is lost as heat.
• India’s biodiversity hotspots are the Himalaya, the Western Ghats, North-East India and the Andaman and Nicobar Islands.
• Communities protect nature: Chipko villagers hugged trees, Mendha Lekha was the first village to win forest rights, and tanks store rainwater.
• A GI tag links a product to its place, like Tezpur Litchi (Assam) or Kandhamal Haldi (Odisha).

Remember

Watch out

• Mixing up the taiga (coniferous forest) and the tundra (treeless, frozen ground).
• Thinking energy grows up a food pyramid: it falls at every level.
• Treating a GI tag as a brand name: it ties a product to the place it comes from.

Worked example