The typical climate of tropical rainforests promotes the growth of millions of plants, animals, and bird species, which directly or indirectly helps us to lead a happy and healthy life. Read this ScienceStruck post to gain more information about the importance of these forests.
Did You Know?
Tropical rainforests that lie within the latitudes 28 degrees north or south of the equator produce 40 percent of the Earth's oxygen. More than 25 percent of natural medicines are obtained from them. Despite all these characteristics, rainforests are the most endangered habitat, as they are being destroyed by human beings for farming and timber.
Rainforests, the green biomes of the world, are a boon to mankind, as they prevent our planet from becoming a dry desert. They are found on lofty mountains or along the seacoasts.
In some parts of the world, they are widely stretched over plains or in river valleys. They are known for the greatest biodiversity on Earth, as they are home to numerous species of plants and animals.
Classification
According to their location and climate, rainforests are classified into tropical and temperate categories. The latter are present along sea coasts in the temperate zone of the Earth (for example, the Pacific Northwest of the USA). The former are found close to the equator, and therefore, they receive ample sunlight.
They are present in the equatorial zone, between the Tropic of Cancer and Tropic of Capricorn. The areas close to the equator are called tropics, and are known for a warm and humid climate throughout the year. No other place on the Earth exhibits such a variety of plants and animals, as found in these areas.
Tropical forests are located in Central and South America, Africa, Asia, and Australia. The Amazon rainforest in South America, spread over 6 million sq. km., is the largest one in the world.
It extends over eight South American countries, namely Brazil, Bolivia, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname, and Venezuela.
These forests are further classified as moist deciduous and semi-evergreen seasonal forests, flooded forests, montane or cloud forests, and lowland equatorial evergreen rain forests, depending on where they are, and what type of climate the region has.
Rainfall
Heavy rain is an invariable part of the weather forecast of the tropical forests.
Predominant heat promotes quick evaporation of water, and the typical climate stimulates sudden downpours all round the year.
Evaporation of the rainwater is responsible for about 50 percent of the precipitation. The average annual rainfall is not less than 168 cm (66 inches), and at times, it can be more than 1000 cm (390 inches).
These forests are the wettest place on our planet as they receive rains every day, and are named as "thirsty forests" as they enjoy about 175 cm (69 in) to 200 cm (79 in) of average rain every year.
As the trees are very tall and dense, the topmost layers receive most of the rainwater. Their leaves work as shields. Less amount of water reaches the ground.
Temperature
The climate is always hot and humid. These areas hardly experience any climate change.
Average monthly temperature is always found above 18°C (64°F). The temperature is usually between 20 - 35°C. The tall trees in these areas have to face strong winds.
Effect of Climate on the Environment
The forest areas have poor soil as the soluble nutrients are often washed away by heavy rains.
The heat and moisture enhance the process of decaying of dead plants and animals. Rotten and decayed organisms supply rich nutrients to the soil. The ongoing natural recycling process, thus, helps enrich the soil.
Plants in these areas rise higher and higher in search of sunlight, which leads to the formation of four sublayers of forests.
The emergent layer is the topmost portion of the rainforest, where widespread branches can absorb maximum sunlight.
With a height of more than 160 feet, the canopy layer turns into a very thick layer of dense interlocked branches and forms an umbrella over other growing plants and trees.
The shorter trees that lie immediately under the canopy layer receive some amount of filtered sunlight. But plants under these layers receive less sunlight, and hence, they are smaller and darker. They display a wide variety of flowers to attract insects.
The forest floor level hardly receives any sunlight. Insects and fungi thrive in this portion as they feed on decomposed matter on the floor.
The soil is very poor, but plants develop stilt roots, prop roots, and buttress roots to absorb maximum nutrients from the soil. Lianas, strangler plants, carnivorous plants, etc., are the characteristic species that are found here.
The adaptability of animals and plants in these regions is really amazing. The dense and wet environment has led to the development of special characteristics in the species that grow over there. Such adaptations have helped them survive.
Rainforests cover only 6% of the Earth's land. Still, they are the greatest source of oxygen, wood, healthy foods like berries, fruits, and several medicines (including some used for cancer treatment). According to expert estimations, if not stopped, human beings would destroy these forests within less than 50 years.
Their destruction is making our Earth warmer. Similarly, severe climate changes due to pollution (for which human beings are responsible) can disrupt the growth of such forests.
We have to take utmost care if we don't want our planet to become a dry and barren land.
The climate of these forests helps regulate the dense growth of trees, which in turn helps maintain the balance of temperature and rain in other parts of the world. Once these forests vanish, we will be deprived of rain and pure air.