Uppermost in our minds recently and all over the news is climate change. We see the fires, we see the flooding, we see the icebergs melting and sea levels rising, and these look like enormous problems to us as individuals. What can we do, we ask ourselves - it seems the best we are doing so far is recycling our rubbish, using low energy lightbulbs, and for those that can afford it, opting for zero-emission cars. Here’s a fact we shouldn’t be proud of – every 1.2 seconds, man destroys an area of forest the size of a football field, with deforestation coming in many forms – fires, clearance cutting for development, and unsustainable logging.
But there is a way we can help - by planting a tree, or more would be better! It has been calculated that the world supports roughly 422 trees for every person on earth, with one tree taking in more than a ton of carbon dioxide in its lifetime. Who knew that NASA, supposedly looking deep into space, was also sneakily looking backwards at us, but for a good reason. For years, they have been snapping photos of our oceans, mountains and forests, and sharing them with ecologists and biologists.
Trees reflect sunshine in distinct patterns, making it possible for satellites to map - and computers to count - strips of land where trees are. Biologists then sample those places – forests, suburbs, parks, even city streets – to assume a tree density, and multiply by acre or hectare. According to a study published in the journal Nature in 2021, it is estimated there are over 3.04 trillion trees on our planet. Before man came along, it is estimated there were 6 trillion trees, so it looks like we are using them up faster than replacing them.
Lungs of the earth
Trees are the lungs of the Earth they say, absorbing pollutants through their leaves, trapping and filtering contaminants in the air. And like all green plants, they produce oxygen through photosynthesis.
Trees lower air temperatures and humidity, and can also influence wind speed. Evaporation of water from trees, called transpiration, has a cooling effect. Cities develop ‘heat islands’ because dark roofs and pavements absorb heat and radiate it back. Trees in car parks have been shown to reduce asphalt temperatures by 36 degs F, and car interiors by up to 47 degrees F.
Economically, three or more large trees placed on the sunny sides of a house can shade it from the hot summer sun, reducing air-conditioning costs by as much as 30%. Coniferous trees, because they retain their needles year-round, serve to reduce wind when placed on the north and northwest sides of a building, resulting in significantly lower winter heating costs.
A belt of trees 100 ft wide and 50 ft tall can reduce intense road noise by up to 10 decibels, reducing the sound volume by half. Densely planted trees can also block unsightly views.
Trees are not like oil - they are renewable. If you think we are using up more than our allotment (which we probably are, when you think about all the things we use wood for), you can always plant a few more. We may be falling behind in our tree count, but it's possible to go out into the woods or the backyard or the hillside with a seed and a shovel and help repair the damage. People shouldn’t have the attitude of ‘oh I will never touch a tree-created product again’, because trees are essential for wildlife, people, and certainly our environment.
Now before you all start going mad and planting tree seeds, saplings or fully grown trees in your efforts to save the planet, there are a few things you should know. First and foremost, you can’t just go out and plant stuff where you think it should be! Trees can only be planted around your local area with the landowners' permission, and you shouldn’t plant trees on archaeological sites, places with rare or protected species, grassland that has never been ploughed, wetlands and heathland. And lastly, if you go planting, leave space for growth, and take note of what grows well in Portugal!