Forests are getting younger and that’s not good news – Radar

Trees around the world are confronted with very changing influences: rising temperatures due to climate change, but also the rise of CO2 in the atmosphere, which acts as a “bemester”. In addition, there are more and more disturbances such as forest fires, droughts, wind damage and other natural enemies of forests. And, of course, there is man-made logging.

Climate change accelerates tree mortality

This combination of factors has led to the average age of trees and the average height falling in the last century, argues the study, which is led by the US Department of Energy and the Birmingham Institute of Forest Research (BIFoR). The results suggest that the age and length of the trees will continue to decline due to ongoing environmental changes.

The increasing drought also promotes tree mortality

“This study provides an overview of the growing number of evidence that climate change is accelerating tree mortality and making the world’s forests younger and shorter,” says Tom Pugh of BIFoR. “This implies a reduction in their ability to store carbon and potentially major changes in the mix of species that make and inhabit these forests.”

Less biodiversity

“This trend is likely to continue with global warming,” said Nate McDowell, lead author of the study. “A future planet with less large, old forests will be very different than we are used to. Older forests often contain much higher biodiversity than young forests and store more carbon.”

The study shows that other mechanisms of change are also underway in forests. For example, rising CO2 levels in the atmosphere can increase the growth and seed production of trees, but this only seems to happen in forests with abundant nutrients and water. Most forests in the world have to do without this abundance, which drastically reduces the benefits of CO2 growth.

The rising temperature, in turn, limits photosynthesis, resulting in lower growth, higher mortality and reduced regeneration. The increasing drought also increases tree mortality. (Ips)

Trees around the world are confronted with very changing influences: rising temperatures due to climate change, but also the rise of CO2 in the atmosphere, which acts as a “bemester”. In addition, there are more and more disturbances such as forest fires, droughts, wind damage and other natural enemies of forests. And, of course, there is man-made logging. This combination of factors has led to the average age of trees and the average height falling in the last century, argues the study, which is led by the US Department of Energy and the Birmingham Institute of Forest Research (BIFoR). The results suggest that the age and length of the trees will continue to decline as a result of ongoing environmental changes. “This study provides an overview of the growing number of evidence that climate change is accelerating tree mortality and making the world’s forests ever younger and shorter,” says Tom Pugh of BIFoR. “This implies a reduction in their ability to store carbon and potentially major changes in the mix of species that make and inhabit these forests.” This trend is likely to continue with global warming,” said Nate McDowell, lead author of the study. “A future planet with less large, old forests will be very different than we are used to. Older forests often contain much higher biodiversity than young forests and store more carbon.” The study shows that other mechanisms of change are also underway in forests. For example, rising CO2 levels in the atmosphere can increase the growth and seed production of trees, but this only seems to happen in forests with abundant nutrients and water. Most forests in the world have to do without this abundance, which drastically reduces the benefits of CO2 growth. The rising temperature, in turn, limits photosynthesis, resulting in lower growth, higher mortality and reduced regeneration. The increasing drought also increases tree mortality. (IPS)