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The Increasing Loss Of Trees Is Creating A Havoc In US, Tree cover in urban zones has declined at a rate of approximately 175,000 acres per year, while impenetrable cover – such as buildings and roads – has increased significantly beyond the country. An estimated 40% of new thick surfaces were in areas where trees used to rise, the study found. The total loss of tree cover reached 1% across cities and surrounding areas in the five years [2009-2014]. As four-fifths of Americans exist in urban areas, it has serious environmental, economic and social ramifications, warned researchers.
“Knowing where these losses are occurring and the magnitude of trade will hopefully facilitate notified discussions on how much tree cover areas want to have in the coming years. And on the functions of urban trees in providing environmental quality and human wellbeing and health,” said David Nowak, co-author of the study, announced in the journal. Urban forests modify climate and reduce carbon emissions, increasing the quality of air and water.
The Increasing Loss Of Trees Is Creating A Havoc In US
They also mitigate rainfall-runoff, offering vital barriers in flood-prone cities. Urban trees also have social advantages, such as improving people’s mental and physical health. Researchers Nowak and Eric Greenfield analysed tree cover in US cities and surrounding areas between 2009 and 2014. They looked specifically at urban areas in all 50 states and the District of Columbia, and a broader category named “urban/community areas”, which includes both urban land and politically defined community areas. They found that 45 states showed a net decline in urban tree cover, with 23 states experiencing significant decreases – resulting in an overall annual net loss of 0.12%, which is comparable to 175,000 acres of tree cover.
There are plenty of causes for the downward trend, from insect infestations to population growth, storms, and old age, all of which have been challenging large numbers of trees. Tree planting schedules haven’t kept up with the decline, either. They’re often hurried out with much fanfare, but follow-through has clearly been lacking. Conniff points out that one “million trees” program ended with less than 53,000 saplings planted. Now and Greenfield conservatively estimates that we’ve lost $96 million in benefits from the lost trees over the period of the study.
They arrived at that number by calculating a narrow set of benefits for urban trees, including air pollution removal, energy conservation, carbon sequestration and avoided emissions (for example, due to lowering the heat island effect). Their $96 million estimates, though, isn’t just conservative, but likely significantly understates the losses. Trees also add thousands of dollars to home values, help lower crime rates, and reduce stress.
They are even correlated with students performing better in school —a tree outside a classroom or cafeteria is associated with better test scores, higher graduation rates, better behaviour, and a higher likelihood of attending a four-year school. Together, these effects could significantly alter a city’s prospects.