Tropical Rainforests

Question 1

How much of the earths surface do tropical rainforests cover?

Answer 1

Tropical rainforests cover about 2% of the earths surface.

Question 2

Where are tropical rainforests found?

Answer 2

They are found in a broad belt close to the equator from South America in the west, through west Africa to Southeast Asia and Australia in the east.

Question 3

What is the climate like in tropical rainforests?

Answer 3

• high temperatures (about 27 degrees)
• high rainfall (over 2,000mm a year)
  The climate creates ideal growing conditions and accounts for the lush vegetation growth

Question 4

What is leaching?

Answer 4

High rainfall
Water soaks into the soil, dissolving and transporting away nutrients.
Removes nutrients from the top soil and redeposits them further down.

Question 5

What roots do trees and plants have?

Answer 5

Shallow roots - nutrients are concentrated in the upper topsoil

Question 6

Where do birds live in the rainforest?

Answer 6

Birds live in the canopy (branches and leaves) high above the forest floor, feeding on seeds and nectar from flowering plants.

Question 7

Where are the nutrients stored in a tropical rainforest?

Answer 7

• majority of nutrients are stored in the biomass (mostly the trees).
• soil contains few nutrients, as any nutrients released by decomposers are quickly absorbed by the trees and plants or leached into the soil by the heavy rainfall.
• few nutrients in the litter store, as decomposers, thriving in the warm and wet conditions, quickly break down dead leaves and branches.

There is a rapid transfer of nutrients - due to the climatic conditions

Question 8

What are plant adaptations in the tropical rainforest?

Answer 8

• Access to sunshine is a key factor promoting strong vertical growth, as shown by the tallest emergent trees ‘punching’ their way through the main canopy to exploit maximum sunlight.

Question 9

What are animal adaptations in the tropical rainforest?

Answer 9

• toucans and parrots have strong beaks for cracking hard nuts which other birds cannot break.
  Bats thrive on the fruits growing in the canopy, which they can reach by flying. They also help to disperse seeds, which pass through their digestive systems.
• Animals may use colour to act as camouflage or to warn predators to leave them alone; for example, brightly coloured poisonous frogs
• Three-toed sloths have long claws, enabling them to climb trees, where they live most of the time, away from forest-floor predators. Algae grow on their fur, helping to camouflage them!

Question 10

What is the structure of the rainforest (in order from top to bottom)?

Answer 10

Emergent layer
Canopy
Under-canopy
Shrub layer
Ground layer

Question 11

Why are there high levels of biodiversity in tropical rainforests?

Answer 11

• wet and warm climate encourages a wiae range of plants and trees to grow. These provide many different natural habitats for animals.
• The rapid recycling of nutrients speeds up plant growth (producers) and
  provides plentiful food for consumers.
• Many parts of tropical rainforests are untouched by people, enabling a range of plants and animals to thrive.

Question 12

What are the main threats to biodiversity in tropical rainforests?

Answer 12

• slash and burn agriculture, creating commercial plantations
• unsustainable timber harvesting
• mining and subsequent pollution of water supplies from toxic metals
• development of roads and settlements