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Rainforests of the World

In this episode we'll learn:

  • Where rainforests are found
  • Rainforests of Mexico (case study)
  • Why rainforests thrive
  • What cultures live in rainforests
  • Problems in the forest

Rainforest Communities

What are Rainforests?
Rainforests are defined by a few factors. Most importantly is the amount and distribution of rainfall. To be a rainforest it must have 200cm of rain a year. Tropical rainforests usually receive a more steady rain around the year while temperate rainforests can vary throughout the year with a pronounced dry season.

Where are they found?
Tropical rainforests are found in a belt around the equator. Half of the world’s rainforests lie within the borders of Brazil, Indonesia, and Zaire. Temperate raiforests extend well above these zones are dependent mostly on the rainfall throughout the year.

Rainforests of Mexico

Rainforests in tropical areas rarely get below 80 degrees Fahrenheit. Temperatures however, rarely get hot either. In fact, the yearly temperature variation is so minimal that temperatures vary more in one day than over the course of the year.

Mexico's RainforestsSoil:
If you’ve ever heard that it’s bad to chop down a rainforest because it won’t grow back, did you know why? It’s because the topsoil in a forest is very thin. The nutrients are quickly washed out of the soil from all the rain. Thus, most of the rain is held in the plant tissues. When the rainforest gets chopped down, it is difficult to sustain any crops because the soil is very poor.

Its been said that the tropical rainforests hold from 50 to 90 percent of all species on earth. It has been very difficult in the past to ascertain the number and diversity of species in the forests because of the layers of the forest. Many canopy trees are hundreds of feet tall, making it difficult to look at animals on the tops. In fact, it's believed that whole communities live only in the tops of the trees and have evaded scientific study because of it.

Mexico's Rainforests

Mexican Rainforests are the most northerly tropical rainforsts in the New World. They start around the latitude of Mexico City and run southward in the lower elevations. These forests hold an amazing number of plants and animals.

Threats in Mexican Rainforests:

Every year in Mexico there is close to 500,000 hectar es of tropical and subtropical rainforests destoried. Because of this, there are at least 285 vertebrate species threatened. Birds, freshwaterfish, amphibians, reptiles and mammals are most at risk by these activities.

Media from Mexico:

In the summer of 2003 our crew traveled through every habitat in Mexico and we discovered some of the most amazing things! We've cataloged and documented many animals along the way, all of which we put into our Mexico Documentary. In the meantime we have.

Bats Mexico VideoBat cave in Mexico's Rainforests: A video where crew member Hazen Audel explores a cave in the Los Tuxtlas Biosphere reserve in Verecruz Mexico.

Text by Rob Nelson

January 12, 2006



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