Researchers have found that the presence of trees in the environment strongly relates with the human health.
This research has been published in the American Journal of Preventive Medicine.
Researchers in this study have done an analysis of 18 years of data from 1,296 counties in 15 states in U.S. They found about 15,000 more deaths from cardiovascular disease and slightly more than 6,000 deaths from lower respiratory disease in the people living in the areas bug-ridden by the emerald ash borer, a beetle that kills ash trees making them treeless, as compared to uninfected areas.
The bug was first found near Detroit, Michigan, in 2002. It attacked all 22 species of North American ash and killed virtually all of them.
Researchers found the same pattern of suffering in the counties with demographic differences like income, race and education.
“There’s a natural tendency to see our findings and conclude that, surely, the higher mortality rates are because of some confounding variable, like income or education, and not the loss of trees,” Geoffrey Donovan, a research forester at the Forest Service’s Pacific Northwest Research Station, said in a statement. “But we saw the same pattern repeated over and over in counties with very different demographic makeups.”
The reason for the association of increased mortality with the increased loss of trees is still not known.
Donovan, G., Butry, D., Michael, Y., Prestemon, J., Liebhold, A., Gatziolis, D., & Mao, M. (2013). The Relationship Between Trees and Human Health American Journal of Preventive Medicine, 44 (2), 139-145 DOI: said in a statement