Rainforests are present on every continent except Antarctica. These are ecosystems made up primarily of evergreen trees that typically receive high rainfall. Tropical rainforests are found near the equator, in regions with high average temperatures and humidity, while temperate rainforests are found mainly in coastal and mountainous areas in mid-latitudes.
A rainforest typically consists of four main layers: the topstory, forest canopy, undergrowth, and forest floor. The upper tier is the crowns of the tallest trees, which reach a height of up to 60 meters. The forest canopy is a dense canopy of crowns about 6 meters thick; it forms a roof that blocks most of the light from penetrating the lower layers, and is home to most of the rainforest’s fauna. Little light enters the undergrowth and is dominated by short, broad-leaved plants such as palms and philodendrons. Not many plants manage to grow on the forest floor; it is full of decaying substances from the upper layers that nourish the roots of the trees.
A feature of tropical forests is that they are, in part, self-irrigated. Plants release water into the atmosphere in what is called the process of transpiration. The moisture helps create the dense cloud cover that hangs over most rainforests. Even when it’s not raining, these clouds keep the rainforest moist and warm.
What threatens tropical forests
Throughout the world, rainforests are being cleared for logging, mining, agriculture, and pastoralism. About 50% of the Amazon rainforest has been destroyed in the past 17 years, and losses continue to rise. Tropical forests currently cover about 6% of the Earth’s surface.
Two countries accounted for 46% of the world’s rainforest loss last year: Brazil, where the Amazon flows, and Indonesia, where forests are cleared to make way for palm oil, which these days can be found in everything from shampoos to crackers. . In other countries, such as Colombia, Côte d’Ivoire, Ghana and the Democratic Republic of the Congo, casualty rates are also on the rise. In many cases, soil damage following clearing of tropical forests makes it difficult to regenerate later, and the biodiversity found in them cannot be replaced.
Why are rainforests important?
By destroying tropical forests, humanity is losing an important natural resource. Tropical forests are centers of biodiversity – they are home to about half of the world’s plants and animals. Rainforests produce, store and filter water, protecting against soil erosion, floods and drought.
Many rainforest plants are used to make medicines, including anti-cancer drugs, as well as to make cosmetics and foods. Trees in the rainforests of the Malaysian island of Borneo produce the substance used in a drug being developed to treat HIV, calanolide A. And Brazilian walnut trees cannot grow anywhere except in untouched areas of the Amazon rainforest, where the trees are pollinated by bees, which also carry pollen from orchids, and their seeds are spread by agoutis, small arboreal mammals. The rainforests are also home to endangered or protected animals such as the Sumatran rhinoceros, orangutans and jaguars.
Rainforest trees also sequester carbon, which is especially important in today’s world when large amounts of greenhouse gas emissions are contributing to climate change.
Everyone can help the rainforests! Support forest conservation efforts in affordable ways, consider ecotourism vacations, and if possible, buy sustainable products that do not use palm oil.