Thick clay lies underneath the soil. Once damaged, the soil of a tropical rainforest takes many years to recover. Temperate rainforests have soil that is richer in nutrients, relatively young and less prone to damage. The rainforests recycle and clean water. Tropical rainforest trees and plants also remove carbon dioxide from the atmosphere and store it in their roots, stems, leaves, and branches.
Rainforests affect the greenhouse effect , which traps heat inside the Earth's atmosphere .
There are many indigenous groups of people who have live in the tropical rainforests. Many of these groups, like the Yanomamo tribe of the Amazon rainforests of Brazil and southern Venezuela, have lived in scattered villages in the rainforests for hundreds or thousands of years. These tribes get their food, clothing, and housing mainly from materials they obtain in the forests. Many also have small gardens in cleared areas of the forest. Since the soil in the rainforest is so poor, the garden areas must be moved after just a few years, and another part of the forest is cleared.