There Are 3 Trillion Trees on the Planet

We're outnumbered -- that comes to 422 trees per human being. But their numbers are dwindling.

There are a whopping 3.04 trillion trees on the planet - or 422 trees per human being - according to a Yale-led study recently published in the journal Nature.

Although that might sound like a lot of trees, human-driven deforestation has had a staggering impact on the world's flora. Researchers estimate that the number of trees on the planet has nearly halved since the dawn of human civilization. More than 15 billion additional trees are lost to human-related causes each year.

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Presently, tree population density is highest in sub-Arctic areas of Russia, Europe and North America. Nearly half of the world's tress, however, are found tropical forests.

The research team utilized satellite imagery, previous peer-reviewed studies and density information from 400,000 forest plots worldwide to estimate the tree population. The only prior attempt to estimate the world's tree population fell short, landing at only 400 billion.

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Study lead author Thomas Crowther, from the Yale School of Forestry & Environmental Studies, hopes that his research will be used to prevent further deforestation and preserve existing forestland.

"This study highlights how much more effort is needed if we are to restore healthy forests worldwide," he said in a news release. "They store huge amounts of carbon, are essential for the cycling of nutrients, for water and air quality, and for countless human services."

This originally appeared on DSCOVRD.

Photographer Beth Moon spent 14 years traveling across the world to find and photograph the world's oldest trees. She spent time in the United States as well as remote areas and reserves in Europe, Asia, the Middle East and Africa. Living up to 500 years, the Heart of the Dragon (pictured) is unique to Socotra island in Yemen. Growing in severe conditions, they have raised their branches upward over time in an effort to obtain moisture from the highland mists -- hence the distinctive appearance of their canopies, like an umbrella blown inside out.

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The legendary Bowthorpe Oak, with its rugged bole, gnarled branches, and great spreading crown, stands in a grassy meadow behind a stone farmhouse in Bourne, Lincolnshire. With a circumference of 40 feet, it competes for the title of largest-girthed living oak in Britain. It is also perhaps the oldest living oak tree, with an estimated age of 1,200 years (give or take a century).

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Above, a desert rose on the island of Socotra in Yemen, a UNESCO World Heritage Site. The trees store water in their trunks to survive the dry climate.

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This Spanish Chestnut on the grounds of Croft Castle in Herefordshire, England, is between four and five centuries old.

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Elegant in shape and form, these strange and magnificent baobabs,

Adansonia grandidieri

, seem to rise effortlessly to heights of 100 feet.

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At Wakehurst Place, set among 170 acres of beautifully manicured gardens, is a gloomy cliff of Ardingly sandstone. A few hundred English winters have eroded the soil, but the yews of these woods have adapted to their surroundings. Tangled, black and menacing, they send their naked roots cascading over the huge greenish-blue rocks of the cliff’s edge, in search of soil to sink into.

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There is something magical about these two stately yews, which act as pillars, framing the north door of the church in Stow-on-the-Wold, Gloucestershire. Not much is known about these trees. It is presumed that they were planted sometime in the 18th century and are the survivors of a formal avenue that led to the church. It has also been suggested that this church door was the inspiration for the Doors of Moria in The Lord of the Rings, as J.R.R. Tolkien is known to have passed through the area.

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Elegant in shape and form, these strange and magnificent baobabs seem to rise effortlessly to heights of 100 feet. They are found only on the island of Madagascar, where they are known as


, Malagasy for ‘mother of the forest.’ These trees are a valuable source of food, fiber, dye, rope and fuel, among other things. The trees in this grove, known as the Avenue of the Baobabs, are approximately 800 years old. Sadly, these 20-25 baobabs are the only survivors of what was once a dense tropical forest. The avenue was granted temporary protected status in 2007, as a prelude to its promised future as Madagascar’s first natural monument.

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