Tropical rainforest ecosystem

Maria is in the tropical rainforest with a guide. She's amazed by everything around her: the tall trees, birds singing, beautiful flowers and insects she's never seen before. There's so much going on even under her feet! Ants and masses of unusual mushrooms everywhere. The guide explains that rainforests have a very particular structure.

Even though every rainforest is slightly different, every rainforest can be divided into four layers. In every layer of the rainforest there are different levels of sunlight and humidity, and many different organisms. Certain trees grow very tall and rise above all the others in height. These trees form the uppermost layer of the rainforest - the emergent layer. The branches and leaves in the treetops of the emergent layer usually spread themselves wide, which allows them to catch all the sunlight they need to grow.

Animals typical for the emergent layer include parrots, eagles, butterflies and monkeys. These animals have special skills that make it possible for them to live there. They can fly between the branches. Monkeys can’t fly but they are able to climb and balance very well! Below this uppermost emergent layer, there is a dense layer of branches and leaves of shorter trees.

This can be several meters thick and is like a roof over everything beneath it. This is called the canopy layer. Many of the plants in the canopy layer produce flowers and fruit, which attract animals. In fact, more animals live in the canopy than any other layer of the rainforest! There are more birds, more monkeys, sloths, spiders, lizards, and hundreds of thousands of insect species!

The thick canopy layer cuts out most of the sunlight and protects from strong wind. The glossy, pointy leaves of the trees repel water and let it drip down, therefore protecting the ground from heavy rainfall too. This creates a dark, humid environment below. Here below the canopy, in the next layer, grow palms and ferns. Palms and ferns have large leaves, which they need to catch as much as possible of the little sunlight coming through.

This is the understory layer. Understory layer plants often produce large, colourful flowers, with strong distinctive smell. Insects can easily locate such flowers, even if it’s too dark at this layer, for them to see well. The dark environment here is a great advantage to animals who use camouflage, such as snakes or chameleons. Humidity in the understory helps amphibians to keep their skin moist.

The understory is also home to many large animals, such as forest elephants and gorillas in Africa, tapirs in Asia, or jaguars in Americas. At the very bottom, below the other three layers, is the forest floor. The forest floor is covered with animal droppings and dead leaves that fall from above, which decay quickly. This is called the forest floor layer. The forest floor is a perfect environment for worms, insects, slugs, and fungi that feed on all the decaying material.

These organisms, called decomposers, break down organic matter into nutrients. Nutrients, in turn, are quickly absorbed by roots of plants. Nutrients help plants grow. Each of the four layers of the rainforest have their own specific characteristics. None of the layers can exist on their own.

What happens in one layer affects what happens in another. In this way, all layers and organisms living in a tropical rainforest create a complex ecosystem. It is the relationships within this ecosystem that make rainforests so amazingly full of life.