Fragile ecosystem

Nature’s bounty: Trees provide services worth $500 million to the world’s megacities

By naturally reducing pollution, processing stormwater and helping in energy saving, nature helps planning authorities avoid cut down certain expenses.

Most people probably don’t think of megacities – urban areas with 10 million or more residents – as being part of nature and hence in need of conservation efforts. New research shows that this perception is not just erroneous but counter-productive, however, as trees actually provide ecosystem services worth millions of dollars to the megacities of Earth every year and have the potential to be doing even more.

Just as they do in forests and other natural ecosystems, trees deliver a variety of ecosystem services in cities. They sequester carbon and reduce air pollution and stormwater runoff, for instance. They cut winter winds and help cool their surroundings in summer via shade and transpiration, as well, leading to avoided greenhouse gas emissions and lower energy bills for owners of homes and buildings.

“Trees have direct and indirect benefits for cooling buildings and reducing human suffering during heat waves,” Theodore Endreny of the College of Environmental Science and Forestry in Syracuse, New York, the lead author of a study published this month in the journal Ecological Modelling, said in a statement. “The direct benefit is shade which keeps the urban area cooler, the indirect benefit is transpiration of stormwater which turns hot air into cooler air.”

Economic value

In order to determine how much these services are worth to megacities, Endreny and team looked at 10 megacities on five continents that lie in five different biome types: Beijing, China; Buenos Aires, Argentina; Cairo, Egypt; Istanbul, Turkey; London, UK; Los Angeles, United States; Mexico City, Mexico; Moscow, Russia; Mumbai, India; and Tokyo, Japan.

The researchers used a tool called i-Tree Canopy to survey each megacity and estimate their levels of tree cover, which ranged from 8.1% in Cairo to 36% in Moscow. On average, about 20% of the 10 megacities examined for the study were covered in tree-based ecosystems.

The team also looked at the potential for each city to increase tree cover, and found that an addition 19% of the land area of each city would provide suitable terrain, on average.

Using detailed estimates of the magnitude and value of tree-based ecosystem services, Endreny and his colleagues determined that all of those trees provide an average of $505 million in benefits to each megacity every year, or about $1.2 million per square kilometre of trees. That’s $35 in free services provided by trees to each megacity resident.

The bulk of that $505 million annual average value of urban trees, some $482 million, is due to reduction of pollutants like carbon monoxide, nitrogen dioxide, sulfur dioxide, and particulate matter released by the burning of fossil fuels. The stormwater processing that is avoided by wastewater facilities thanks to trees is worth another $11 million per year, while carbon sequestration is worth $8 million and energy savings are worth $0.5 million, the researchers found

Endreny suggests that these benefits could be nearly doubled if those cities were to make use of additional land areas that are suitable for planting more trees.

“Megacities can increase these benefits on average by 85%,” he said. “If trees were to be established throughout their potential cover area, they would serve to filter air and water pollutants and reduce building energy use, and improve human well-being while providing habitat and resources for other species in the urban area.”

Endreny and his colleagues note that, as of 2016, there were 40 megacities with a combined 722 million residents, which is nearly 10% of the total human population, all of whom “would benefit from nature conservation plans where they work and live.”

The researchers write in the study that a shift in how we think about trees’ place in urban landscapes may be necessary to unlock the full potential benefits of urban trees, however: “The most common mind set separates cities from the rest of nature, as if they were not special kinds of natural habitats. Instead, awareness that urban systems are also nature and do host biodiversity and ecosystem services opportunities, should push urban people towards increased urban forest conservation and implementation strategies.”

Sergio Ulgiati, a professor at the University Parthenope of Naples, Italy and a co-author of the study, said in a statement that, in order to follow up on the findings of the present research, the University had created an Urban Wellbeing Laboratory to be jointly run by researchers and local stakeholders.

“A deeper awareness of the economic value of free services provided by nature may increase our willingness to invest efforts and resources into natural capital conservation and correct exploitation, so that societal wealth, economic stability and well-being would also increase,” Ulgiati said.

This article first appeared on Mongabay.

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Ten awesome TV shows to get over your post-GoT blues

With those withdrawal symptoms kicking in, all you need is a good rebound show.

Hangovers tend to have a debilitating effect on various human faculties, but a timely cure can ease that hollow feeling generally felt in the pit of the stomach. The Game of Thrones Season 7 finale has left us with that similar empty feeling, worsened by an official statement on the 16-month-long wait to witness The Great War. That indeed is a long time away from our friends Dany, Jon, Queen C and even sweet, sweet Podrick. While nothing can quite replace the frosty thrill of Game of Thrones, here’s a list of awesome shows, several having won multiple Emmy awards, that are sure to vanquish those nasty withdrawal symptoms:

1. Billions

There is no better setting for high stakes white collar crime than the Big Apple. And featuring a suited-up Paul Giamatti going head-to-head with the rich and ruthless Damien Lewis in New York, what’s not to like? Only two seasons young, this ShowTime original series promises a wolf-of-wall-street style showcase of power, corruption and untold riches. Billions is a great high-octane drama option if you want to keep the momentum going post GoT.

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2. Westworld

What do you get when the makers of the Dark Knight Trilogy and the studio behind Game of Thrones collaborate to remake a Michael Crichton classic? Westworld brings together two worlds: an imagined future and the old American West, with cowboys, gun slingers - the works. This sci-fi series manages to hold on to a dark secret by wrapping it with the excitement and adventure of the wild west. Once the plot is unwrapped, the secret reveals itself as a genius interpretation of human nature and what it means to be human. Regardless of what headspace you’re in, this Emmy-nominated series will absorb you in its expansive and futuristic world. If you don’t find all of the above compelling enough, you may want to watch Westworld simply because George RR Martin himself recommends it! Westworld will return for season 2 in the spring of 2018.

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3. Big Little Lies

It’s a distinct possibility that your first impressions of this show, whether you form those from the trailer or opening sequence, will make you think this is just another sun-kissed and glossy Californian drama. Until, the dark theme of BLL descends like an eerie mist, that is. With the serious acting chops of Reese Witherspoon and Nicole Kidman as leads, this murder mystery is one of a kind. Adapted from author Liane Moriarty’s book, this female-led show has received accolades for shattering the one-dimensional portrayal of women on TV. Despite the stellar star cast, this Emmy-nominated show wasn’t easy to make. You should watch Big Little Lies if only for Reese Witherspoon’s long struggle to get it off the ground.

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4. The Night of

The Night Of is one of the few crime dramas featuring South Asians without resorting to tired stereotypes. It’s the kind of show that will keep you in its grip with its mysterious plotline, have you rooting for its characters and leave you devastated and furious. While the narrative revolves around a murder and the mystery that surrounds it, its undertones raises questions on racial, class and courtroom politics. If you’re a fan of True Detective or Law & Order and are looking for something serious and thoughtful, look no further than this series of critical acclaim.

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5. American Horror Story

As the name suggests, AHS is a horror anthology for those who can stomach some gore and more. In its 6 seasons, the show has covered a wide range of horror settings like a murder house, freak shows, asylums etc. and the latest season is set to explore cults. Fans of Sarah Paulson and Jessica Lange are in for a treat, as are Lady Gaga’s fans. If you pride yourself on not being weak of the heart, give American Horror Story a try.

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6. Empire

At its heart, Empire is a simple show about a family business. It just so happens that this family business is a bit different from the sort you are probably accustomed to, because this business entails running a record label, managing artistes and when push comes to shove, dealing with rivals in a permanent sort of manner. Empire treads some unique ground as a fairly violent show that also happens to be a musical. Lead actors Taraji P Henson and Terrence Howard certainly make it worth your while to visit this universe, but it’s the constantly evolving interpersonal relations and bevy of cameo appearances that’ll make you stay. If you’re a fan of hip hop, you’ll enjoy a peek into the world that makes it happen. Hey, even if you aren’t one, you might just grow fond of rap and hip hop.

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7. Modern Family

When everything else fails, it’s comforting to know that the family will always be there to lift your spirits and keep you chuckling. And by the family we mean the Dunphys, Pritchetts and Tuckers, obviously. Modern Family portrays the hues of familial bonds with an honesty that most family shows would gloss over. Eight seasons in, the show’s characters like Gloria and Phil Dunphy have taken on legendary proportions in their fans’ minds as they navigate their relationships with relentless bumbling humour. If you’re tired of irritating one-liners or shows that try too hard, a Modern Family marathon is in order. This multiple-Emmy-winning sitcom is worth revisiting, especially since the brand new season 9 premiers on 28th September 2017.

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8. The Deuce

Headlined by James Franco and Maggi Gyllenhaal, The Deuce is not just about the dazzle of the 1970s, with the hippest New York crowd dancing to disco in gloriously flamboyant outfits. What it IS about is the city’s nooks and crannies that contain its underbelly thriving on a drug epidemic. The series portrays the harsh reality of New York city in the 70s following the legalisation of the porn industry intertwined with the turbulence caused by mob violence. You’ll be hooked if you are a fan of The Wire and American Hustle, but keep in mind it’s grimmer and grittier. The Deuce offers a turbulent ride which will leave you wanting more.

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9. Dexter

In case you’re feeling vengeful, you can always get the spite out of your system vicariously by watching Dexter, our favourite serial killer. This vigilante killer doesn’t hide behind a mask or a costume, but sneaks around like a criminal, targeting the bad guys that have slipped through the justice system. From its premier in 2006 to its series finale in 2013, the Emmy-nominated Michael C Hall, as Dexter, has kept fans in awe of the scientific precision in which he conducts his kills. For those who haven’t seen the show, the opening credits give an accurate glimpse of how captivating the next 45 minutes will be. If it’s been a while since you watched in awe as the opening credits rolled, maybe you should revisit the world’s most loved psychopath for nostalgia’s sake.

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10. Rome

If you’re still craving an epic drama with extensive settings and a grandiose plot and sub-plots, Rome, co-produced by HBO and BBC, is where your search stops. Rome is a historical drama that takes you through an overwhelming journey of Ancient Rome’s transition from a republic to an empire. And when it comes to tastes, this series provides the similar full-bodied flavour that you’ve grown to love about Game of Thrones. There’s a lot to take away for those who grew up quoting Julius Caesar, and for those looking for a realistic depiction of the legendary gladiators. If you’re a history buff, give this Emmy-winning show a try.

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For your next obsession, Hotstar Premium has you covered with its wide collection of the most watched shows in the world. Apart from the ones we’ve recommended, Indian viewers can now easily watch other universally loved shows such as Silicon Valley and Prison Break, and movies including all titles from the Marvel and Disney universe. So take control of your life again post the Game of Thrones gloom and sign up for the Hotstar Premium membership here.

This article was produced by the Scroll marketing team on behalf of Hotstar and not by the Scroll editorial team.