Ecology—When air becomes wood

Higher carbon dioxide levels caused 30 percent more wood growth in young forest stands across the temperate United States over a decade, according to an analysis led by Oak Ridge National Laboratory. Scientists examined large-scale experimental plots using mixed model analysis to determine if carbon dioxide caused growth in fast turnover tissues such as roots and leaves or if it resulted in trees with taller, wider trunks that capture and hold carbon dioxide in the wood. “We used methods that take site-to-site variation into account and give a population-level result,” said ORNL’s Anthony Walker. “This provided an estimate of the broader response of these ecosystems to the atmospheric carbon dioxide concentrations of the future.” Studying these changes on a decadal scale improves climate modeling. The findings, published in Nature Communications, are an outcome of the Department of Energy’s carbon dioxide enrichment experiments conducted at ORNL, Rhinelander, Duke and Kennedy Space Center.