Tropical rainforests – who doesn’t know them? Birds chirping, greenery everywhere, and toucans swooping overhead: the pictures aren’t entirely inaccurate, either. These are certainly features of the tropical forest biome. The tropical rainforest is a particularly welcoming environment.
OVERVIEW
A biome is simply a large area with a similar grouping of plants and animals that have adapted to survive in a certain climate and geography.
Tropical rainforests are located near the equator, from latitudes 23.5 degrees N to 23.5 degrees S.
The three largest rainforests are the American, African and Asian rainforests. Each has its own group of plant and animal species, ranging from many types of monkeys to birds, trees, and ground cover. Even within a rainforest, the species in a region may vary widely due to environmental limitations.
CHARACTERISTICS
-Tropical forests do not have winter, and the seasons are simply “rainy” or “dry”. Even then, the rainfall is fairly evenly distributed in some types of rainforests.
-The temperature varies little, being on average from 20-30 degrees Celsius throughout the entire year.
-The canopy of trees overhead is almost continuous, and little sunlight reaches the ground underneath it. The branches on a tree are concentrated near the top, since branches further down wouldn’t get any light. Often, there are 100-foot sections of trunks with no branches at all!
-There are several types of rainforests, and they are categorized depending on how much rainfall they receive from season to season.
PLANTS AND ANIMALS
Over half of the Earth’s species live in the rainforests that cover just 6% of the Earth’s land surface. There is an incredible diversity in plants, too. Tropical rainforests have more varieties of trees than anywhere else. One study found 100-300 species in just one hectare of rainforest.
70% of the plants in a rainforest biome are trees. Most plant life like herbs and bushes can’t grow below, because they are sheltered by the thick canopy and can’t get any light. There are several layers of life in the rainforests:
1. The upper (emergent) trees are the tallest, from 100 to 240 feet.
2. The upper canopy, with trees from 60 to 130 feet tall, is the most important layer in some ways. Many animals live in this layer and never even touch the ground, since there is a complete environment available for them there.
3. The lower canopy consists of trees up to 60 feet in height. This layer is in shade from the thick canopy above it, and constantly humid, with little air movement.
4. The forest floor is the most shaded, with less than 1% of the sunlight filtering through to reach it. It is easy to walk through most areas because of the lack of undergrowth. The trees roots depend on the organic matter that decomposes rapidly at this level.
Monkeys, birds, insects, and other types of animals abound in rainforests. Anywhere from 40 to 100 animal species might live in a single hectare of rain forest. Most rainforest species, however, are insects.
CONCLUSION
The rainforest biome is one of the most interesting, diverse, and valuable on the Earth. At least thousands of species of animals and plants exist here and nowhere else, and the trees supply valuable oxygen to humans living not only there, but also in other biomes across the world.
