PLEA Network

29 October 2015, Yale Connections, Long-Term Drought Impacts on Trees. Scientists find that droughts harm trees for longer than previously understood. ANDEREGG: “We’ve known for decades that drought has harmful effects on trees. That during drought they grow slower and they have a higher chance of death.” That’s William Anderegg, a biologist at the University of Utah. He says until recently, researchers were not clear about what happened to the trees after a drought ended. So his team looked at the growth of trees after severe drought in more than a thousand forests across North America, Europe, and Asia. They found that even four years after a drought, trees continued to grow more slowly than normal. ANDEREGG: “Trees take up about a quarter of human emissions of CO2 each year, and that’s a very big slowing effect on climate change. So if droughts cause forests to take up less carbon, that could very much speed up the pace and the severity of climate change.” Anderegg says it is too early to know what the long-term implications will be. ANDEREGG: “Some of our best models suggest that forests could be relatively resilient and others suggest they could really die off en masse and lose a lot of their carbon to the atmosphere. And we don’t know which of those is more likely.” But Anderegg says that the future of the world’s forests is still in our hands. ANDEREGG: “I always like to emphasize that a lot of that future does depend on human decisions and what we do about climate change.” Read More here