Rainforest Facts

Rainforests are forests which grow in areas of high rainfall. Tropical rainforests are found between the Tropic of Cancer and the Tropic of Capricorn. Those nearest the equator, where the climate is very hot and wet all through the year, are evergreen because the trees can grow all the time and so are always in leaf. Further away from the equator, the climate is more temperate and there are wet and dry seasons. The rainforests in these areas are deciduous and the trees lose their leaves during the dry seasons.
            
These deciduous rainforests are found, for example, in the cooler parts of Central America and India.

Cloud forests are yet another type of rainforest, so-called because they can be found high up mountains, where they are nearly always in cloud. The climate here is very cool but extremely wet.

Before humans started destroying the rainforests, they covered 15% of the Earth's land area. Today, they cover less than 7%. In the last 200 years, the total area of rainforest has decreased from 1,500 million hectares to less than 800 million hectares. (One hectare is equivalent to the area covered by two football pitches). More than a hectare of rainforest is lost every two seconds, which means that at present rates of destruction, there will be no rainforest at all in just 40 years.

The disappearance of the forest is called DEFORESTATION. As populations have grown and demands for land and timber have grown greater, so the deforestation has accelerated. Logging only began in Indonesia ten years ago. It is estimated that in just ten more years, the timber stock will have been totally destroyed. In Thailand, 80% of the country's original forest has been cut down in the last 40 years.
            
    
Why are Rainforests Important?

Biodiversity
Climate
Erosion and Flooding
Medicine & Food

What are the Threats to the Rainforest?

Humans have cut down trees for thousands of years, yet concern over deforestation is fairly recent. The rate at which the forests have been cleared has accelerated during the latter part of this century. Since the end of the Second World War about half the world's rainforest has been felled. Gradually, the rainforest has gained the attention of the worldwide media, making most of us aware of the problems.

Forests are destroyed for a number of reasons:-

Population Growth
Tropical Hardwood
Cattle Grazing

The Future

Can the rainforests be replaced?
What can be done

Conserving rainforests is, and will probably continue to be, an extremely difficult challenge. The countries with rainforests are trying to cope with their immediate problems, brought about by population increase and enormous debts to the World Bank, so they have little time to think about the long-term effects of removing the forests. A shortage of money prevents these countries from carrying out suitable conservation programmes.

Only with financial assistance from developed countries, or by writing off all or at least part of the debts, can the rainforests be saved. This will not happen overnight. There is too much money at stake, and only strong public feeling in developed countries will lead to pressure being brought against those in control of Third World debt to help rainforest countries. Until this happens, the economic situation will force countries with rainforests to carry on cutting them down.

It is estimated that every minute, 80 football pitches of rainforest are destroyed! Each day, at least one species of animal or plant becomes extinct! There is little hope of preserving all the remaining rainforests exactly as they are today. Parts of them should be protected absolutely, but others can be used to benefit man as well as other species. There is no reason why development cannot harmonise with the forest. In this way we will be able to ensure that the unique rainforests, with their great diversity and importance for the environment, continue to survive.


Ideas for Projects

1. Pollinating The Plants
Birds, bats, bees, butterflies and moths all play an important role in the reproduction of rainforest plants. In most ecosystems, the pollen is carried from one plant to another by the wind. In a rainforest ecosystem, however, there is hardly any wind at all, so the animals are vitally important for plant pollination.

    * What adaptations have rainforest plants and animals evolved to help with pollination?
    * How do the plants attract the animals?
    * Describe some specific examples of interdependence (the relationships between the animals and plants).

2. Dispering The Seeds
Some species of monkeys, bats and birds are very important seed dispersers. Even some species of fish are responsible for dispersing seeds! The plants produce large numbers of seeds and hope that at least some of them will be spread around the forest and end up in suitable places for germination. Without animals' help, this spreading around of the seeds would not be possible.

    * How do plants attract the seed-dispersing animals?
    * Describe how different types of animals manage to disperse seeds around the rainforest.

3. Predator and Prey
As in other ecosystems, most rainforest animals are herbivores (they eat plants), but some of them are carnivores and eat other animals. The animal predators come in many shapes and sizes, and include spiders, insects, amphibians,reptiles, birds and mammals. The largest predators, which are at the top of the food chain, are known as indicator species. These predators, such as the jaguar of South America and the tiger of India, need a lot of living space, and if an area of forest has a healthy population of such animals, then we can be pretty sure that the whole forest community is doing well. Any destruction of forest habitat, or a decrease in numbers of their prey will affect the population of large predators.

    * Choose one of the groups of predators mentioned above, and find out details about where they live, their way of hunting, their prey etc.
    * Construct food chains, and perhaps a food web, which include the predators you have chosen.


4. People of the Forest
Indigenous tribes (groups of people who come from a country or area) have only lived in rainforests for a short period in human history. In South East Asia and the Pacific Islands, people have lived in the forests for about 40,000 years, but the earliest signs of human settlement in African forests are no more than 3,000 years old. There are about 1,000 indigenous tribes in the rainforests of the world. Even though they may not have been there for very long, rainforest people have managed to develop ways of life which allow them to use the forest without destroying it. Whilst other civilisations have grown further and further from the natural world, rainforest people have had to grow close to nature in order to survive.    
      
Information supplied by the Young Peoples Trust for the Environment