Como viabilizar a proteção à arborização urbana?

John Schults/Reuters

How Should We Pay for Street Trees?

Teresa Mathew

A new report argues that the urban canopy should be considered—and funded—as a part of a city’s public health infrastructure.
Trees have proved to aid mental health, decrease obesity and other health risks, and just generally make people happier. But they are often thought of as a luxury rather than a vital component of healthcare or urban infrastructure. In a new report, The Nature Conservancy, a conservation-focused nonprofit, argues that trees are an important public health asset and should be funded as such.

“Just like the public health sector has gotten used to thinking about walkable cities as something they need to care about, we’re advocating that they need to think about nature and parks as part of that quest,” says Robert McDonald, a lead scientist at The Nature Conservancy and co-author of the report.

McDonald hopes that cities will start to integrate urban forestry into their other health, wellness, and environmental initiatives. Despite the benefits, there are multiple reasons why tree planting falls by the wayside. For one, it’s a process that often requires the coordination of multiple agencies—not just forestry, but other departments like transportation and water. “We’ve set up our cities so there’s one agency to manage trees and parks, and they don’t have a health mandate. Other agencies do care about health, but don’t have a mandate to plant trees,” McDonald explains. Cities often do not see the link between residents’ health and the presence of trees.

McDonald says that bringing different agencies together and including nature in planning conversations would be an important first step in forging that link. He offers up the example of Toronto, where the public health department worked with the forestry department to tackle the city’s urban heat island. Because many buildings in Toronto don’t have air conditioning—a growing problem as temperatures rise—the two departments collaborated to strategically place street trees in neighborhoods where people are especially vulnerable to the heat due to their socioeconomic status or age.

Cost can be another deterrent. Tree planting expenditures appear to be popular with residents: According to The Trust for Public Land’s Land Vote Database, voters across the U.S. have approved 75 percent of ballot measures that fund land conservation, parks, and other greening projects. But municipal governments often remain unconvinced. Although many cities do have a budget for tree maintenance, the Nature Conservancy report finds those allotments inadequate. Since 1980, the average municipal spending on urban forestry in the U.S. has fallen by over 25 percent. Today, the average municipal expenditure on tree planting is $5.83 per capita.

But as much as trees can cost a city, there is evidence showing they have significant monetary value. Researchers at SUNY’s College of Environmental Studies and Forestry estimated that trees in megacities carry a payoff of roughly $500 million, including half a million dollars saved in cooling costs and $11 million saved through improved storm water remediation.

“We’re trying to get people to think of street trees not just as ‘nice-to-have’ things, but as a piece of infrastructure for your city that you’d be willing to invest in with a bond,” says McDonald, “just as you’d be willing to with another health or infrastructure [initiative].”

To stretch government investment, some communities are turning to corporate and philanthropic grants. In New York, for example, the MillionTreesNYC program, which aims to increase the city’s urban forest by encouraging residents to plant trees, was partially financed by donations from foundations such as Bloomberg Philanthropies. In 2016, health conglomerate Kaiser Permanente invested $2 million in organizations working to preserve parks. Kaiser is also partneringwith scientific researchers to see if policy holders are healthier when they have nature nearby. This, McDonald says, is “the first step in the process of linking the healthcare sector to the urban forestry sector.”

McDonald is hoping that more philanthropists and corporations in the healthcare sphere become galvanized to take up the issue of urban forestry. “If you look at the successful cities, most of them are looking at sustainability,” he says. “And we think nature, for health, should be a centerpiece of those plans.”

This article is part of a series highlighting the themes of CityLab Paris, a convening of urban leaders.


Fonte: CityLab