This photo essay is part of a series on the planet’s major ecosystems, a topic that will be discussed at the Global Landscapes Forum New York on 28 September.
Forests cover 31 percent of the world’s total land area and store an estimated 296 gigatons of carbon in above- and below-ground biomass. About 1.6 billion people around the world depend on forests for their livelihoods, and some 300 million people worldwide live in forests.
About 400 million years ago in the Devonian Period, forests are thought to have first emerged from plants that had advanced onto land from water. As forests grew, they created shade, shielding other life forms from the direct sun and allowing them to flourish.
Forests are highly efficient ecosystems. Their high rate of photosynthesis affects plant and animal systems in a series of complex organic relationships. A full-canopied forest absorbs between 60 and 90 percent of available light, most of which is absorbed by the leaves for photosynthesis.
Forests can play a significant role in mitigating climate change through carbon sequestration. One recent study found that restoring the world’s forests – planting billions of trees across the planet – is by far the most effective and cost-effective way of combating climate change.
More than 25 percent of the medicines we use originate in rainforest plants, but only 1 percent of these plants have been studied for their medicinal properties.
Urban forests also play an important role in improving air quality in cities. They can reduce air temperatures by up to 8 degrees Celsius, significantly reducing air conditioning needs, and also remove harmful pollutants and fine particulates from the air.
Read the rest of our ‘fast facts’ series on ecosystems below.