Yale Environment 360 discusses whether Climate Change will upend projections of future forest growth. While the world’s forests can play an important role in absorbing carbon dioxide and slowing climate change, new research indicates that elevated CO2 concentrations do not necessarily boost forests and that higher temperatures could cause changes in trees that reduce their ability grow.
In a eucalyptus forest just west of Sydney, Australia, six open towers made of 25-meter-tall white pipes poke above the treetops. In 2012, carbon dioxide gas started flowing from the tubes, raising levels inside the rings to nearly 40 percent above the global average CO2 concentration of around 405 parts per million. For four years, trees soaked in the carbon bath, building some of it into leaves, roots, and wood, and respiring the rest. When ecologist Mingkai Jiang of Western Sydney University and colleagues measured the results of all this activity, they were shocked. Despite gorging on plant food in the form of CO2, the trees hadn’t managed to grow any larger, the researchers reported in April in Nature.