Rainforest

Rainforests are thick, green forests with tall trees that form a roof-like cover called a canopy. They are special because they are full of life, with many plants, animals, and tiny organisms living together. You can find rainforests in warm places like Mexico, Madagascar, and Borneo, as well as cooler areas such as Washington state.

These forests are very important because they are home to many different species, and scientists believe there are still millions of plants, insects, and tiny living things we haven’t discovered yet. Tropical rainforests have been called the “jewels of the Earth” and the “world’s largest pharmacy” because many natural medicines come from them.

However, rainforests and the animals that live there are disappearing quickly. This happens because people cut down trees, which destroys the homes of many creatures, and also because of pollution in the air. Protecting rainforests is very important for keeping our planet healthy and full of life.

Definition

Rainforests are forests with tall, closely spaced trees that form a continuous roof-like layer, known as a canopy. They are very wet and humid, with lots of plants that need moisture to grow. Rainforests can be found in warm areas near the equator, called tropical rainforests, or in cooler areas, called temperate rainforests. There are also other types, like subtropical rainforests and dry rainforests, each with their own special features.

Main article: Tropical rainforest

Main article: Temperate rainforest

Tropical rainforests grow in hot, wet places close to the equator, where it hardly ever gets dry. These forests are found in places like Southeast Asia, Sub-Saharan Africa, South America, Central America, Australia, and Pacific Islands. They are sometimes called the "Earth's lungs" because they help clean the air.

Temperate rainforests grow in cooler areas of the world, such as North America, parts of Europe, East Asia, southern Chile, Australia, and New Zealand. These forests are also very wet but not as hot as tropical rainforests.

Dry rainforests have fewer trees and less rain than other rainforests. They grow in places where mountains block the rain, such as in parts of Australia. These forests have plants with special ways to survive with less water, like thick, tough leaves or sharp thorns.

Layers

Main article: Stratification (vegetation)

Tropical rainforests have different layers, each with special plants and animals. The emergent layer has very tall trees, sometimes as high as 80 meters, with eagles, butterflies, bats, and monkeys living there. The canopy layer is full of large trees and many plants, home to lots of insects and other creatures. The understory layer has bigger leaves and is where birds, snakes, and animals like jaguars live. Finally, the forest floor gets very little sunlight and is covered with plants that can grow in the dark, along with fungi that help break down dead plants and animals.

Main article: Canopy (biology)

Main article: Understory

Main article: Forest floor

Flora and fauna

Rainforests are home to a huge variety of plants and animals. Many types of vascular plants grow in tropical rainforests, along with many mammals, reptiles, amphibians, birds, and invertebrates. You can find animals like primates, felids, snakes, turtles, and colorful birds. There are also many fungi that help break down dead plants and animals.

The many hiding spots in rainforests, such as tall trees and dense bushes, help animals stay safe from predators and provide many places for plants to grow. This variety of hiding places supports a lot of life, making rainforests very rich in different species. Some animals, like certain reptiles, are seeing fewer numbers, so scientists watch them closely to help protect them.

Soils

In tropical rainforests, the soil is often poor in quality even though there is lots of vegetation. This is because bacteria break down organic matter quickly, preventing the buildup of rich, dark soil called humus. The soil can become red due to minerals like iron and aluminium, and trees usually have shallow roots since nutrients are found near the surface in the top layer of leaves and animals.

When rainforest trees are removed, rain can wash away the soil, leading to erosion. The soil is also very acidic, which makes it hard for plants to take in nutrients. Additionally, the type of clay in the soil does not hold onto nutrients well, so even if nutrients are added, they often wash away with the heavy rain.

Effect on global climate

Rainforests play a big role in our planet's air. They take in and release lots of carbon dioxide, but when left alone, they balance out so they don’t change the air much. However, when humans cut down trees, called deforestation, the forests start to release more carbon dioxide. This can change the climate, and some models show that droughts and other problems might cause big changes in forests like the Amazon by around 2050.

Human uses

Further information: Tropical rainforest § Human dimensions

Tropical rainforests give us important things like timber, food, and medicine. They are also popular tourism spots and help the environment in many ways. However, many people take from these forests without giving anything back, which can harm the plants and animals that live there.

Many different groups of people have lived in rainforests for a very long time. In places like Brazil and West Papua, there are tribes that have never had much contact with the outside world. These tribes face big challenges because forests are being cut down. Other groups, like the Mbuti and pygmies in Central Africa, and many tribes in Sarawak — part of the island of Borneo — have rich cultures and traditions tied to the rainforest.

Deforestation

Further information: Deforestation in Southeast Asia, Deforestation in Madagascar, and Deforestation of the Amazon Rainforest

Tropical and temperate rainforests have faced heavy logging and clearing for valuable woods and farming land throughout the last century. As a result, the area covered by rainforests worldwide is getting smaller every year. Biologists believe that many plant and animal species are disappearing because their homes are being destroyed.

Cities are also growing into areas where rainforests once stood. In some places, like along the coasts of eastern Australia, very few rainforests are left. In West Africa, almost 90% of the rainforest has already disappeared. In Madagascar, two thirds of the original rainforest is gone. If things continue at the same pace, rainforests in Indonesia could be gone in just ten years.

Some countries, like Brazil, have declared this loss of forests an emergency. However, there is also good news—new forests are growing in some areas where old forests were cut down.