Rainforests have been around for millions of years and contain over half of all living things in the world. Located near to the equator, they have remained in place even during the ice ages and have had a prolonged period of time to develop and become incredibly specialised. A common misconception is that the abundant wildlife means the soil must be good but this is often not the case.
What are rainforests?
Also spelled rain forest. A dense forest found in areas of heavy rainfall.
Types of rainforest:
The tropical rainforests are mostly found within 10 degrees north or south of the equator where the temperature is hot all year round and the rainfall can be heavy (over 250 cm rainfall a year).
Rich in wildlife, plants are broad-leaved and evergreen and grow in three layers: undergrowth, intermediate trees and shrubs, canopy. Rainforests are home to half of the worlds plants and animals.
They are found on every continent except Antarctica.
The amazon rainforest is the largest rainforest in the world.
There are some tribes in the African and Amazon rainforests that have yet to have any contact with the outside world.
4. An area of rainforest the size of a football field is destroyed each second.
5. Rainforests used to cover 14% of the earth but now only cover 6%.
6. The trees are so densely packed that rain can take 10 minutes to reach the ground after hitting the canopy.
7. The soil in rainforests is actually thin and quite poor. The plants have had millions of years to evolve to get used to the poor soil conditions.
The high rainfall leads to large surface runoff which leads to large rivers. There are many large rivers in rainforest areas.
Monkey face flower
An average 10 km square of rainforest might include:
750 species of tree and...
1500 species of flowering plant
This plant has heart shaped flowers that look like they are bleeding.
These giant lily pads are strong enough to support a child's weight!
Some trees grow so tall that they have special 'buttress roots' to hold them up.
Special drip tips help shed the heavy rain.
Source of medicines
One quarter of our medicines come from rainforest plants and it is thought that there are many more potential medicines that could come from rainforest plants that have yet to be identified.
80% of the plants in the rainforest are unique to the rainforest.
The behaviour of baby orangutans is not that dissimilar from baby humans
The squirrel monkeys live in the canopy layer of the rainforest.
Toucans don't actually fly that far and have small wings as a result.
Many animals in the rainforest face the threat of extinction. Animals that are endangered are becoming so few in number that their very future as a species starts to look doubtful.
There are different levels of endangered animals as you can see in this diagram. This diagram ranks all animals from extinct to least concern.
The eastern lowland gorilla is endangered!
Tropical rainforests are found in areas of heavy rainfall mostly close to the equator. Temperate rainforests are found in areas of heavy rainfall close to the coast. This map shows the location of the wolrd's rainforests. For more rainforest maps, click on the link below.
The rainforests are home to many tribes of indigenous people that make their livelihoods from the rainforest in a sustainable way.
Some examples of indigenous groups that live in rainforest regions include: The Yanomami of Brazil, the Penan of Sarawak, and the Desana of Columbia.
There are four layers of plants in the rainforest. These are:
The emergent layer
The understory and
There are animals that only live in the canopy for example and similarly, animals that only live in the undergrowth.
Similiarly, there are plants which don't even have their roots in the soil. Lianas are a vine like plant that get all their water from the rainfall.
Deforestation is when the trees are chopped down.
They are mostly chopped down for farming.
Rainforests used to cover 14% of all the land in the world, now they cover only 6% of the land.
Every second, an area the size of a football field is chopped down.
Copping down trees is hard work so the forest is often set on fire to clear the land.
Tropical rainforests have pretty much the same weather every day. They are near to the equator so it is hot all year round. That means that there is no winter, or autumn or spring for that matter.
They experience heavy rainfall throughout most of the year.
Temperate rainforests are different in that they still have rain all year round but they are cooler.