The Environmental Contribution of Trees
By Tali Orad / 1Treellion, CEO/Founder
Photo credit Christian / Unsplash
A friend once told me that once everyone know the level of contribution trees have on our environment they will stop cutting down trees, and my team and I at 1treellion will be ready to retire. Unfortunately, we are far from that moment as 15 billion trees are lost annually to deforestation. If you open the page on “trees” at Britannica’s dictionary, after the botany definition you will find a description of how trees play a fundamental role in our survival and that they are “perhaps not fully appreciated”. Trees play an integral role in the world ecosystem, they support almost every system, and it’s time we give them the credit they deserve.
AIR
Air is a mixture of gases that is composed of 78% Nitrogen, 21% Oxygen, and a very small percentage of water vapor and other gases. The fact that air contains so much oxygen is not because the earth provided us the atmosphere with that composition, but because living beings like trees and others, produced oxygen billion of years ago from carbon dioxide, and are continuing to do so. By this process we gain two things:
Clean air – The world’s forests absorb a third of global emissions every year. Particles, odors, and
pollutant gases such as nitrogen oxides, sulfur dioxide, and ammonia settle on the leaves of the tree. The trees absorb these toxic chemicals through their stomata (‘pores’), effectively filtering these chemicals from the air.
Temperature regulated air – Air has another important function, and it is regulating the temperature of the earth and creating different weather patterns. Without the atmosphere’s moderating effect, the earth would be extremely hot during the day and freezing cold at night.
However, air pollution, which contributes to the greenhouse gas effect, is changing the balance and threatening the existence of life and may alter climatic patterns.
Trees help mitigate the greenhouse gas effect by trapping heat, reducing ground-level ozone levels, and releasing life-giving oxygen. For example, tropical forests can provide 23% of the climate mitigation needed over the next decade to meet the goals of the Paris Agreement set in 2015.
WATER
The quality of water as well as controlling the water cycle by regulating precipitation, evaporation, and flows, are all processes trees take part in.
Purify the water – Just like cleaning the air we breathe, trees help clean the water we drink. Forests absorb rainfall and use that water to refill underground aquifers, cleansing and cooling water along the way. Certain tree species even break down pollutants commonly found in urban soils, groundwater, and runoff, such as metals, pesticides, and solvents. Control it – Trees serve as natural sponges, collecting and filtering rainwater, and releasing it slowly into streams and rivers. Absorb it – Their roots grip the ground and anchor the tree as it keeps soil from washing away, and filters harmful substances out of the water as it soaks downward. If trees are not there we may find the area dry, susceptible to flash floods, and where water reserved is, contaminated. Cost-effective – By using trees within the water purifying process we actually save money, not just after the fact, for restoring and rebuilding after a disaster, but also in the purification process.
One example of an urban area that depends on forested land for water purification is New York City. In the late 1990s, New York City leaders balked at a $6 billion water treatment system and instead opted to go with natural landscape management to clean the water it receives from the Catskill/Delaware watershed in upstate New York. The evaluation showed it would cost $7 billion to build a water treatment plant, compared with a $1 billion bill for actively managing the forest catchment area by raising water taxes and paying farmers to use less fertilizer and reduce grazing.
SOIL
The majority of trees, if not all, need soil to grow, but they don’t just extract nutrition from the soil, they give to it as well, by protecting it and nurturing it.
Nurture – The way trees nurture the soil is obviously different than humans nurturing their children. The organic matter of the soil develops primarily from decayed leaves, twigs, branches, roots, and fallen trees, all of which recycle nitrogen, carbon, oxygen, and other important nutrients. Keeping our soil healthy, enable the soil to efficiently store and recycle carbon, water, and nutrients such as nitrogen and phosphorous.
Protect – Soil erosion is a natural process that occurs in all landforms and has occurred on planet Earth for millions of years. Wind and rain are two of the main forces that erode bare soil. Raindrops gain momentum as they fall, which provides enough force to move particles of dirt when they reach the ground. Having soil erosion may create the circumstances for desertification, it pollutes our waterways and creates the potential for flooding and landslides. Unfortunately, human activities expedite the erosion process which has gone from being a gradual one (taken place over decades or centuries) to a much faster one. Soil erosion and soil fertility are the major two components of land degradation. This is one of the world’s most pressing environmental problems and it will worsen if we don’t act. Both lead to progressively lower crop yields, increased costs of production, and may end up in land abandonment and desertification.
Globally, about 25% of the total land area has been degraded, undermining the well-being of 3.2 billion people. Scientists recently warned that 24 billion tons of fertile soil were being lost per year, largely due to unsustainable agriculture practices. If this trend continues, 95% of the Earth’s land areas could become degraded by 2050. And would potentially force hundreds of millions of people to migrate, as food production collapses in many places, the report warns.
This is where the biological solution, provided by mother nature (tree), can help.
Trees are actually holding soils together, and with that prevent erosion. The roots, in particular of large trees, can extend well beyond the point where the branches end. They are there to provide stability for the tree and to absorb nutrients and water mostly from the top layer of the soil. Roots vary in size from large roots for strength to tiny roots for absorption. This network that is created weaves through the top layer of soil and binds it all together, keeping it in place and preventing soil erosion.
HABITAT
Where there is water, healthy soil, and trees you will also find animals. Trees support a healthy
ecosystem providing food and shelter to animals. They provide habitat to over 80% of the world’s terrestrial biodiversity. A single tree can be home to hundreds of species of plants, mammals, birds, insects, and fungi. Depending on the kind of food and shelter they need, different forest animals require different types of habitat. Without trees, forest creatures would have nowhere to call home.
A report by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services
(IPBES) indicated that 25% of plants and animals assessed — totaling 1 million species worldwide — are threatened with extinction. A separate study found that 680 vertebrate species are on the brink, each with fewer than a thousand individuals remaining in the wild.
Forests cover about 30 percent of the planet’s landmass, but humans are cutting them down, clearing these essential habitats on a massive scale. Which leads to rapid loss of species. The loss we are seeing today is estimated by experts to be between 1,000 and 10,000 times higher than the natural extinction rate.
Turning forests, grasslands, and other areas into farms, cities, and other developments is the reason for habitat losses. We cannot bring back the species that are lost, but we can make sure those that are here, will stay.
Bottom line is that trees play an integral role in the world ecosystem, they support most of them
and improve them. It is time we give them the credit they deserve. Next time you walk by a tree, pause, observe, appreciate it, and if you can, plant a tree.
Written by Tali Orad, 1Treellion CEO/Founder
Tali Orad is a changemaker, an engineer, TEDx speaker, and serial entrepreneur. She is the founder of 1treellion.org an NGO with the mission to collectively make a meaningful global impact by bringing communities together to plant trees and help mitigate the effects of climate change. More about the work of 1treellion and on TED.com.