CLOSE
iStock
iStock

Trees Save Big Cities $500 Million Each Year

iStock
iStock

As if you really needed another reason to hug a tree: Scientists writing in the journal Ecological Modeling say trees in big cities deliver more than $500 million in environmental benefits every year.

A tree is a marvel of biology. Unfussed by the pull of gravity, it sucks water upward; unembarrassed by its resourcefulness, it makes food out of the waste gases we leave behind. And that’s just what it does for itself; for us, it does even more, cleaning our air, beautifying our neighborhoods, improving our health and well-being, reducing our energy use, and helping us beat the heat.

"Trees have direct and indirect benefits for cooling buildings and reducing human suffering during heat waves," lead author Theodore Endreny of the SUNY College of Environmental Science and Forestry 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."

Endreny and his colleagues wondered how these qualitative effects might translate into dollars, or rubles, or rupees. The researchers used a tool called i-Tree Eco to estimate the amount of tree cover in 10 huge cities: Beijing, Buenos Aires, Cairo, Istanbul, London, Los Angeles, Mexico City, Moscow, Mumbai, and Tokyo.

These densely packed megacities are home to almost 10 percent of the entire human population of Earth—people whose lives often depend on natural environments outside city limits.

“What is, however, most often disregarded,” the authors note, “is that nature conservation in the city can also contribute to human well-being benefits. The most common mind set separates cities from the rest of nature, as if they were not special kinds of natural habitats.”

Their results showed that those urban natural habitats occupied about 21 percent of each megacity landscape. That’s a lot of tree cover, but there could be a lot more; on average, the researchers found another 19 percent of land that could be given over to vegetation.

The data suggested that filling this space with trees could increase environmental and cost benefits by an average of 85 percent.

As they are now, the trees are already saving megacities gobs and gobs of money—about $1.2 million per square mile, or $35 per resident, per year.

"Placing these results on the larger scale of socioeconomic systems makes evident to what extent nature supports our individual and community well-being by providing ecosystem services for free," co-author Sergio Ulgiati of Italy’s University Parthenope said in the statement.

"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."

nextArticle.image_alt|e
Michael Gottschalk, AFP/Getty Images
arrow
environment
Germany Wants to Fight Air Pollution With Free Public Transit
Michael Gottschalk, AFP/Getty Images
Michael Gottschalk, AFP/Getty Images

Getting people out of their cars is an essential part of combating climate change. By one estimate, getting people to ditch their two-car household for just one car and a public transit commute could save up to 30 percent in carbon dioxide emissions [PDF]. But how do you convince commuters to take the train or the bus? In Germany, the answer may be making all public transit free, according to The Local.

According to a letter from three of Germany's government ministers to the European Union Environment Commissioner, in 2018, Germany will test free public transit in five western German cities, including Bonn. Germany has failed to meet EU air pollution limits for several years, and has been warned that it could face heavy fines if the country doesn't clean up its air. In a report from 2017, the European Environment Agency estimated that 80,767 premature deaths in Germany in 2014 were due to air pollution.

City officials in the regions where free transport will be tested say there may be some difficulty getting ahold of enough electric buses to support the increase in ridership, though, and their systems will likely need more trains and bus lines to make the plan work.

Germany isn't the first to test out free public transportation, though it may be the first to do it on a nation-wide level. The Estonian capital of Tallinn tried in 2013, with less-than-stellar results. Ridership didn't surge as high as expected—one study found that the elimination of fares only resulted in a 1.2 percent increase in demand for service. And that doesn't necessarily mean that those new riders were jumping out of their cars, since those who would otherwise bike or walk might take the opportunity to hop on the bus more often if they don't have to load a transit card.

Transportation isn't prohibitively expensive in Germany, and Germans already ride public transit at much higher rates than people do in the U.S. In Berlin, it costs about $4 a ride—more expensive than a ride in Paris or Madrid but about what you'd pay in Geneva, and cheaper than the lowest fare in London. And there are already discounts for kids, students, and the elderly. While that doesn't necessarily mean making public transit free isn't worth it, it does mean that eliminating fares might not make the huge dent in car emissions that the government hopes it will.

What could bring in more riders? Improving existing service. According to research on transportation ridership, doing things like improving waits and transfer times bring in far more new riders than reducing fares. As one study puts it, "This seldom happens, however, since transport managers often cannot resist the idea of reducing passenger fares even though the practice is known to have less impact on ridership."

The same study notes that increasing the prices of other modes of transit (say, making road tolls and parking fees higher to make driving the more expensive choice) is a more effective way of forcing people out of their cars and onto trains and buses. But that tends to be more unpopular than just giving people free bus passes.

[h/t The Local]

nextArticle.image_alt|e
WWF
arrow
Animals
Watch an Antarctic Minke Whale Feed in a First-of-Its-Kind Video
WWF
WWF

New research from the World Wildlife Fund is giving us a rare glimpse into the world of the mysterious minke whale. The WWF worked with Australian Antarctic researchers to tag minke whales with cameras for the first time, watching where and how the animals feed.

The camera attaches to the whale's body with suction cups. In the case of the video below, the camera accidentally slid down the side of the minke whale's body, providing an unexpected look at the way its throat moves as it feeds.

Minke whales are one of the smallest baleen whales, but they're still pretty substantial animals, growing 30 to 35 feet long and weighing up to 20,000 pounds. Unlike other baleen whales, though, they're small enough to maneuver in tight spaces like within sea ice, a helpful adaptation for living in Antarctic waters. They feed by lunging through the sea, gulping huge amounts of water along with krill and small fish, and then filtering the mix through their baleen.

The WWF video shows just how quickly the minke can process this treat-laden water. The whale could lunge, process, and lunge again every 10 seconds. "He was like a Pac-Man continuously feeding," Ari Friedlaender, the lead scientist on the project, described in a press statement.

The video research, conducted under the International Whaling Commission's Southern Ocean Research Partnership, is part of WWF's efforts to protect critical feeding areas for whales in the region.

If that's not enough whale for you, you can also watch the full 13-minute research video below:

SECTIONS

arrow
LIVE SMARTER