There is much decay on this level, which returns nutrients back into the soil. Rainforest Facts Rainforests cover 2 percent of the earth's surface, or 7 percent of its land mass. Tropical rainforests are the Earth's oldest continuous ecosystem. Fossil records show that the forests of South East Asia have existed for 70 to 100 million years. An area of rainforest cleared for farming or grazing cattle becomes unproductive in only a few years.
Tropical rainforests are the most diverse ecosystems on earth.
Native rainforest plants, insects and other animals form a fragile network that cycles and returns the most nutrients possible out of the poor soil. Tiny Panama has as many species of plants as all of Europe. Ecuador, which is about the size of Colorado, has twice as many species of birds as the United States and Canada combined. While there are many species of plants in a square-mile of tropical rainforest, there may only be one or two of each. Removing one plant can severely damage the fragile ecosystem.