Image of the Day: Changing Forests
Image of the Day: Changing Forests

Image of the Day: Changing Forests

Carbon dioxide and temperature need to increase in a constant ratio for plants to keep up with climate change.

Emily Makowski
Nov 27, 2019

ABOVE: Aspen forest with drought-induced leaf die-off, which could happen more frequently if drought increases due to climate change and trees can’t adapt

Climate change could be good news for plants due to increased atmospheric carbon dioxide, which encourages photosynthesis. But it could also lead to higher temperatures and dried-out soil—conditions that hinder plant growth. The degree to which climate change helps or hurts plants depends in part on whether forests can acclimate to shifting conditions, according to a study published Monday (November 25) in PNAS.

Researchers led by ecologist John Sperry at the University of Utah created models of how groups of trees in 20 forested areas across the US would respond to climate change. They focused on regionally abundant types such as birch, spruce, aspen, poplar, and pine. In some of the simulations, the team enabled forests to acclimate to climate change by balancing their density and tree growth with the constraints of reduced water and increased heat. In other scenarios, these characteristics remained the same, representing an inability to adapt to a shifting climate. In the simulations, forests that acclimated were still able to thrive, but only if there was enough of an increase in carbon dioxide to keep up with rising temperatures. 

J.S. Sperry et al., “The impact of rising CO2 and acclimation on the response of US forests to global warming,” PNAS, doi:10.1073/pnas.1913072116, 2019.

Emily Makowski is an intern at The Scientist. Email her at