m17.   What’s happening to the tropical forests?

About 56% of the world's tropical forests have been cleared or damaged. The annual rate of loss rose 50% between 1981 and 1991 (vanishing at a rate of about 2 football fields per second).  An equal area of forest is damaged every year.

About 95% of Brazil's rainforests are on the Atlantic Coast, and 98% of the Araucaria forests (southern Brazil) have been lost to logging.  All cutting of native vegetation was halted in 1990 along the Atlantic Coast, but reforestation occurs at a rate of 1 new tree for every 10 cut.

Nearly 20% of tropical rainforest species will be gone by 2022; 50% by 2042. Rainforest products harvested sustainably include hardwoods, food products (coffee, tea, cocoa, spices, nuts, chocolate, and tropical fruits), and other products (latex rubber, resins, dyes, essential oils). Around 25% of the world's prescription drugs are substances extracted from plants growing in tropical rainforests.

About 70% of the 3,000 plants identified by the National Cancer Institute as sources of cancer-fighting chemicals come from tropical rainforests. There may by tens of thousands of strains of plants with potential food value in the rainforests. Destruction of the tropical rainforests, resulting in loss of water and topsoil, and flooding will cause as many as a billion people to starve to death in the next 30 years.

e01.    What is biodiversity?

e03.    How do pathogens and insects affect trees?

e06.    What is “wilderness” and how much do we have?

e08.    What are bioregions and biosphere reserves?

e09.    What is succession?

e10.    Why do organisms become extinct?

e12.    Where are tropical forests?

e23.    How is soil important to plants?

g05.    How are forests of geological importance?

g22.    What is soil?

g23.    What are some characteristics of soil?

g24.    How does soil move?

g27.    How fast are supplies of mineral being used up?