Presentation on theme: "What is a rainforest? Rainforests are warm, wet, dense forests. They contain millions of animal and plant life. These forests are important to the earth."— Presentation transcript:
What is a rainforest? Rainforests are warm, wet, dense forests. They contain millions of animal and plant life. These forests are important to the earth. They provide many resources for medicines and are a great supply of oxygen.
There are two different types of rainforests; temperate and tropical. Temperate rainforests have wet and dry seasons. The soil is richer in nutrients, younger and less prone to damage. Tropical rainforests do not really have seasons. The soil is thick and ancient. Clay lies under the surface. Once the soil is damaged it may take years to recover.
Rainforests are found near the equator. South and Central America, Africa, Australia and Asia all contain rainforests. The largest rainforest is located in the Amazon River Basin, the Congo River Basin and throughout much of southern Asia.
It is almost always raining in the rainforest, hence the name rain forest. Each year rainforests get over 80 inches of rain a year. This is about 1 ½ inches of a rain a week. In a tropical rainforest the rain is evenly distributed during the year. In a temperate rainforest there are wet and dry seasons. During the dry season there is fog that gives the rainforest its moisture.
Rainforests are very important to the earth. They recycle and provide clean water. The trees and plants that grow in the rainforest remove carbon dioxide from the air. The store it in their roots, stems, leaves and branches. They also provide many cures for our common sicknesses and diseases.
Rainforests are sometimes called “The World’s Largest Pharmacy” because more than half of our medicines today have originated from the rainforest. Some of these medicines have been treatments for… Asthma Childhood leukemia Cancer Currently there are 121 prescription drugs sold worldwide from plant derived sources. Even so, only 1% of the plants have been tested.
Some plants like the trumpet flower, contain atropine and scopolamine compounds, long known to open airways during asthma –These are also know to induce hallucinations and possible death. The jimsonweed, is known to help asthma when it was thrown into a fire and the smoke inhaled, so it was made into cigarettes which could be smoked to treat asthma attacks.
Rosy periwinkle was discovered to kill caner cells. The plant Vinca provided the chemicals needed for two successful cancer drugs; vincristine and viblastine.
Opium came from the poppy plant and was used as a painkiller. Quinine was used to prevent malaria and came from the quina tree. Steroid hormones came from yams.
The rainforest has given us all of these amazing things we can use. But these resources are being destroyed daily. Rainforests used to cover 14% of the earth, and now they only cover 7%. Experts estimate that in the rest of the rainforests could be destroyed in less than 40 years. If all of these rainforests are destroyed we may lose many important cures and treatment for illnesses and diseases.
Some people believe that leaving the rainforests intact and harvesting its many goods, would turn a greater profit than just cutting them down for timber or cattle grazing land.