Most people recognise that trees play an essential role in the environment, but they perhaps undervalue the true extent of these incredible organisms’ benefits. Trees provide oxygen and limit carbon in the atmosphere. They reduce air pollution, provide food and shelter for wildlife, minimise erosion and maintain healthy soil, increase rainfall, and absorb sunlight as energy. Simply, trees are an essential component of life on Earth.
Depending on the type, size and condition of a tree, the amount of carbon it takes out of the atmosphere varies widely. A single tree can absorb as much as 22 kilos of carbon in a year, and sequester 0.90 tonnes in total by the time it reaches 40 years of age. The same tree will add enough oxygen to the atmosphere to support between two and four people for a year. Trees also increase air quality by filtering a variety of pollutants including heavy dust particles. They effectively absorb harmful gases such as sulfur dioxide, carbon monoxide and nitrogen dioxide. Trees also naturally clean pollutants out of the soil and either store them in their root systems or convert them into less toxic substances.
Surprisingly, trees can have a dramatic effect on the weather systems in their area. Because of their size and the extent of their root structures, they often pump large amounts of water out of the ground. As they sit in the sunlight, much of this water evaporates through the leaves into the atmosphere. Through this process, a forest of trees can create a significant amount of the rainfall it needs for its own and the entire ecosystem’s survival.
Trees are one of the great solar energy collectors in the world. Virtually all energy on earth comes from the sun, and trees are the most effective living organisms at transferring that light into energy. In fact, trees are responsible for collecting as much as 50% of all energy collected by life from the sun. Numerous animals then eat tree leaves, flowers, bark, fruit and chutes, transferring that energy further into the ecosystem. Leaves also fall from the trees and are broken down by microbes in the soil to create nutrient rich fertiliser for other plants.
The immense size and extent of trees make them important to their local environment too. They cool the ground around them, providing shelter for animals and appropriate conditions for a variety of plants to grow. They block wind that can cause soil deposits. Trees also are essential in holding water and soil within the ecosystem. Without trees, bare soil is quickly stripped of its nourishing topsoil by heavy rain, which either runs off into the ocean or rivers and streams that fill up with silt.
Trees are also the oldest and largest organisms on the planet. There are Bristlecone Pines that are over 5,000 years old and Giant Sequoia trees with a volume of almost 1,500 cubic metres. Trees cover 31% of the earth’s land surface, over 4 billion hectares.