A study published in the Environment International journal has found that planting more trees could result in healthier and longer lives for a population. The findings come after researchers found a correlation between the longevity and health of a certain population when about 50,000 trees were planted in thirty years.
The Friends of Trees Initiative planted trees in Oregon
The Friends of Trees campaign in Oregon planted 49,246 trees in Portland from 1990 to 2029. The group kept records of the places and the times they had planted these trees. There have been several studies looking into the link between trees and the risk of death. However, these studies have been unreliable. The study authors had hoped to change that.
According to a researcher from ISGlobal and lead study author, Payam Dadvand, previous studies evaluated vegetation index by satellite imaging. Unfortunately, this technique could not differentiate vegetation and translate data into tangible interventions.
How researchers conducted the study
The researchers used a population of about 4000 people for their study. These people had lived in an area where the Friend of Trees group had planted trees for 5 to 15 years. The team used information from a report by the Oregon Health Authority. The report contained data on deaths caused by respiratory, cardiovascular, and other non-accidental means in the area.
From the results, the researchers concluded that neighborhoods with more trees were less likely to die from respiratory and cardiovascular causes. These findings were more apparent in people above 65. Furthermore, trees that had been around for 11 to 15 years seemed to have a more positive effect than those that had been there for 1 to 5 years. From this, the team concluded that while planting trees was crucial to health, taking care of those already in existence was more important.
Although the study proved the relationship between trees and lower mortality rates, it did not explain how trees could improve the health of populations. Researchers were interested in how older trees had a stronger impact on health as it proved certain theories. Experts believe that older trees are better at absorbing carbon dioxide and regulating temperature hence are better for improving health.
The researchers concluded that planting trees was a worthwhile investment for city officials.
