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  • [In some Native languages the term for plants translates to 'those who take care of us.'"]

  • This is the tale of two ancient cities and the trees that determined their destinies.

  • In 3,000 BC Uruk was more densely populated than modern day New York City. [75.000 people in 6 km2]

  • This crowded capital had to continually expand their irrigation system to feed its growing population.

  • 2,500 years later in Sri Lanka, the city of Anuradhapura had a similar problem.

  • They were also growing constantly, and like Uruk, their city relied heavily on an elaborate irrigation system.

  • As Uruk grew, its farmers began chopping down trees to make space for more crops.

  • In Anuradhapura, however, trees were sacred.

  • Their city housed an offshoot of the Bodhi tree under which Buddha himself was said to have attained enlightenment.

  • Religious reverence slowed farmer's axes and even led the city to plant additional trees in urban parks.

  • Initially, Uruk's expansion worked well.

  • But without trees to filter their water supply, Uruk's irrigation system became contaminated.

  • Evaporating water left mineral deposits, which rendered the soil too salty for agriculture.

  • Conversely, Anuradhapura's irrigation system was designed to work in concert with the surrounding forest.

  • Their city eventually grew to more than twice Uruk's population, and today, Anuradhapura still cares for a tree planted over 2,000 years ago.

  • We may think of nature as being unconnected to our urban spaces, but trees have always been an essential part of successful cities.

  • Trees act like a natural sponge, absorbing storm water runoff before releasing it back into the atmosphere.

  • The webs of their roots protect against mudslides while allowing soil to retain water and filter out toxins.

  • Roots help prevent floods, while reducing the need for storm drains and water treatment plants.

  • Their porous leaves purify the air by trapping carbon and other pollutants, making them essential in the fight against climate change.

  • Humanity has been uncovering these arboreal benefits for centuries.

  • But trees aren't just crucial to the health of a city's infrastructure; they play a vital role in the health of its citizens as well.

  • In the 1870s, Manhattan had few trees outside the island's parks.

  • Without trees to provide shade, buildings absorbed up to nine times more solar radiation during deadly summer heat waves.

  • Combined with the period's poor sanitation standards, the oppressive heat made the city a breeding ground for bacteria like cholera.

  • In modern day Hong Kong, tall skyscrapers and underground infrastructure make it difficult for trees to grow.

  • This contributes to the city's dangerously poor air quality, which can cause bronchitis and diminished lung function.

  • Trees affect our mental health as well.

  • Research indicates that the presence of green foliage increases attention spans and decreases stress levels.

  • It's even been shown that hospital patients with views of brick walls recover more slowly than those with views of trees.

  • Fortunately, many cities are full of views like thisand that's no accident.

  • As early as the 18th century, city planners began to embrace the importance of urban trees.

  • In 1733, Colonel James Oglethorpe planned the city of Savannah, Georgia to ensure that no neighborhood was more than a two-minute walk from a park.

  • After World War II, Copenhagen directed all new development along five arterieseach sandwiched between a park.

  • This layout increased the city's resilience to pollution and natural disasters.

  • And urban trees don't just benefit people.

  • Portland's Forest Park preserves the region's natural biodiversity, making the city home to various local plants, 112 bird species, and 62 species of mammals.

  • No city is more committed to trees than Singapore.

  • Since 1967, Singapore's government has planted over 1.2 million trees, including those within 50-meter tall vertical gardens called supertrees.

  • These structures sustain themselves and nearby conservatories with solar energy and collected rainwater.

  • Trees and vegetation currently cover over 50% of Singapore's landmass, reducing the need for air conditioning and encouraging low-pollution transportation.

  • By 2050, it's estimated that over 65 percent of the world will be living in cities.

  • City planners can lay an eco-friendly foundation, but it's up to the people who live in these urban forests to make them homes for more than humans.

  • The time to get involved with the climate movement is now.

  • Don't know where to start?

  • We've partnered with the U.N. to create a 30-day challenge designed to teach you everything you need to know to become a part of the solution.

  • Start the challenge with a friend or family member today.

[In some Native languages the term for plants translates to 'those who take care of us.'"]

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    Mackenzie posted on 2020/07/06
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