How Trees Reduce Air Pollution

The biggest problem of human being is how to reduce air pollution. Trees absorb odors and pollutant gases (nitrogen oxides, ammonia, sulfur dioxide and ozone) and filter particulates out of the air by trapping them on their leaves and bark.

In the current climate, we’re regularly inundate from all sides about pollution, minimizing our ecological footprint and protecting our environment. At times it can be overwhelming to know where to even start! In addition to our regular duties of reducing, reusing and recycling, have you thought about planting trees? Read on to discover how planting trees can make an enormous, positive contribution to the health of our environment!

What causes air pollution?

Industrial human activities, such as the burning of greenhouse gases, release toxic chemicals and particles into the air. Concentrations are worse in crowded urban areas, and countries with huge manufacturing industries – such as China, India and Bangladesh – have the highest recorded levels globally. So we have to thing globally how to reduce air pollution.

Emissions from vehicles also contribute to poor air quality. In developing countries, deforestation and burning charcoal and wood for fuel is a driving factor. Cutting down trees not only releases CO2, but also prevents forests from purifying our air.

Many governments have an air pollution index and have set targets for ‘safe’ levels of air pollution, but almost every country is currently exceeding dangerous levels.

Trees are able to clean the air and absorb harmful airborne particles and gaseous pollutants. Toxins such as nitrogen oxides, ammonia and sulfur dioxide through their leaves, bark and roots. This improves the air quality in the micro-climate around the trees and contributes to a healthier and cleaner environment overall. Trees also soak up the harmful carbon dioxide in our atmosphere. In one year, an acre of mature trees absorbs the same volume of carbon monoxide as produced from a 26,000 mile car journey! Aside from cleaning the air for us, trees supply us with fresh oxygen to breathe. This is the time when we have to take action to reduce air pollution not getting too late.

Due to excess gases being produced from large-scale industrial processes, heat from the sun’s rays gets trapped in the Earth’s atmosphere – this is known as ‘the greenhouse effect ’ and it is contributing to the overall rise of Earth’s temperature. It doesn’t sound like much, but an average global warming of even 1.5 degrees could cause accelerated icecap melting, severe drought and sea-level rise and the loss of many keystone species such as bees, whales and elephants. Trees planted in an urban environment can not only counteract the warming effects concrete and buildings have on the environment (known as the urban heat island effect), they have also been shown to clean the air of pollutants and particulates created by traffic that are harmful to us. Through the process of photosynthesis, trees are able to absorb carbon dioxide from our atmosphere and reduce the ‘greenhouse effect’, creating a less polluted, more sustainable world for our future generations.

Woodlands have proven to be an invaluable asset when it comes to improving air quality and reducing harmful pollutant levels in the atmosphere. This is why we should try our best to ensure that our most valuable woodlands, like the rain forests, aren’t being lost to deforestation. Many areas of rain forest are being sold off to the highest bidder, their beautiful trees (and the important habitat they create for wildlife) being destroyed to make way for areas to graze cattle (reared for beef) or grow unsustainable palm (to create palm oil). When going about your daily life, try to support brands who choose not to work in association with deforestation. Instead, look for foods that use sustainably sourced palm oil and use the Roundtable on Sustainable Palm Oil (RSPO) logo. Buying products like bananas and coffee that have the Rainforest Alliance certification ensures that minimal impact is being done to produce these foods. Reducing our meat intake and supporting local butchers when we do fancy a Sunday roast is always a great way to reduce the impact our lifestyles have on deforestation. Together we share a responsibility to be good stewards of our planet, and it’s the small things that can make some of the biggest differences!

The message we want you to take away from this is clear – appreciate your trees! Plant them, gift them, and protect them. Let’s try to get as many out into the world as possible!

The relationship between trees and air pollution is a complicated one. Particulate matter suspended in polluted air tends to settle onto leaves, and certain gases including nitrous dioxide (NO₂) are absorbed by leaves’ stomata, filtering the air and reducing pollution levels slightly.

But trees and other vegetation also restrict airflow in their immediate vicinity, preventing pollution from being diluted by currents of cleaner air. In particular, tall trees with thick canopies planted alongside busy roads can act like a roof, trapping pockets of polluted air at ground level. To reliably improve air quality, city planners need to give careful consideration to how trees are placed.