Theme: Tree in a city, How trees grow, National Parks. Tree in a city

Trees create a cooling effect.

Concrete streets, parking lots and asphalt buildings can increase urban temperature by around 3-7 degrees. By transpiring water and providing shade, trees are known to reduce this heat and create a cooling effect on local temperatures. With proper urban street tree planting, an average household in the city can also save around 15% to 35% off their energy bills.

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   Trees provide health benefits to citizens.
   

With their capacity to protect people from pollution and harsh weather, trees are helpful to those who are suffering from asthma, skin cancer, hypertension and other stress-related sicknesses.
Trees can also address noise pollution issues that bother most people living in cities. Each mature tree can reduce unwanted noise by up to 6 decibels, while a vertical wall of trees serves as a buffer to loud street sounds.

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   Trees improve the mental health of citizens
   

Aside from the physical health advantages, they also improve the overall mental health of people too.
Being surrounded by trees lowers the level of stress hormones (cortisol) in our brains. Through their calming influence and therapeutic effect, they reduce the risk of stress and anxiety in a population.

Central Park with Manhattan skyscrapers over Turtle Pond, New York

6. 
   Trees allow cities to save costs.
   

A research performed in the U.K. by Natural England reported that every £1 spent on tree planting yielded £7 savings – which equated over £2.1 billion, if taken nationally.
This is because, throughout their lifetimes, trees provide tangible benefits twice the amount invested into planting and caring for them. Such benefits can range from climate change mitigation, ecosystems conservation, disaster prevention, livelihood improvement and sustainable infrastructures.

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