Tropical Rainforests

Question 1

Climate

Answer 1

• Very wet with over 2,000 of rainfall per year.
• Very warm with an average daily temperature of 28°C. The temperature never drops below 20°C and rarely exceeds 35°C.
• The atmosphere is hot and humid.
• The climate is consistent all year round. There are no seasons.

Question 2

Soil

Answer 2

• Most of the soil is not fertile but is fertilised by the heavy rainfall.
• A thin layer of fertile soil is found at the surface where the dead leaves decompose.
• It is red in colour because it is rich in iron.
• Due to heavy rainfall the nutrients are quickly washed out of the soil.

Question 3

Plant and animals

Answer 3

• The warm and very wet climate provides perfect conditions for plant growth.
• The wide range of plant species supports many different animals, birds and insects.
• Species have adapted to the conditions of the rainforest, eg trees and plants have shallow-reaching roots to absorb nutrients from the thin fertile layer in the soil.

Question 4

Structure of a tropical rainforest

Answer 4

In order the tropical rainforest is made up of the following layers:
- ground level
- shrub layer
- under canopy
-(main) canopy
- emergents

Question 5

Lianas

Answer 5

These are woody vines that have roots in the ground but climb up the trees to reach the sunlight. Their leaves and flowers grow in the canopy.

Question 6

Tree trunks

Answer 6

These are tall and thin to allow trees to reach the sunlight. The bark on these trees is smooth to allow water to flow down to the roots easily.

Question 7

Drip tips

Answer 7

Plants have leaves with point tips. This allows water to run off the leaves quickly without damaging or breaking them.

Question 8

Buttress roots

Answer 8

Large roots have ridges which create a large surface area that help to support large trees.

Question 9

Epiphytes

Answer 9

These are plants which live on the branches of trees high up in the canopy. They get their nutrients from the air and water, not from the soil.

Question 10

Animal adaptations

Answer 10

• The sloth uses camouflage and moves very slowly to make it difficult for predators to spot.
• The spider monkey has long, strong limbs to help it to climb through the rainforest trees.
• The flying frog has fully webbed hands and feet, and a flap of loose skin that stretches between its limbs, which allows it to glide from plant to plant.
• The toucan has a long, large bill to allow it to reach and cut fruit from branches that are too weak to support its weight.

Question 11

Deforestation Reasons

Answer 11

• Farming
• Logging
• Mining
• Roads
• Hydroelectric power
• Population

Question 12

Impacts of tropical rainforest loss

Answer 12

• Soil erosion: refers to the removal of soil particles due to natural agents such as wind, water, and ice.
• Loss of biodiversity (animals and plants): due to deforestation as they are closely connected through the food web.
• Climate change: The plants of the Amazon Basin absorbs carbon dioxide so by fewer trees being able to absorb Co2 more is being emitted into the environment (contributing to global warming).
• Economic development: the creation of mines, farms and roads have required more space therefore more trees have had to be cut down to make space.

Question 13

Sustainable management of tropical rainforests

Answer 13

• Logging and replanting: selective logging of mature trees ensure the rainforest canopy is preserved
• Education
• Ecotourism
• International agreements