Amazon’s ability to absorb carbon from its atmosphere has fallen by about 50% in comparison to the 1990s and nearly 100 researches led by University of Leeds, England. This was reported in Nature. The Amazon reached an annual peak of 2 billion tonnes in atmospheric carbon capture during the 1990s. However, the Amazon cannot absorb any of the Latin American fossil fuel emissions. This study that analyzed the data from the South American rainforest for the last 30 decades found an enormous increase in tree death rates. Researchers monitored 321 plots throughout the rainforest. Image Credit: Georgia Pickavance, GLC 2000). Dr. Roelbrienen from Leeds University, School of Geography said that the increase in atmospheric carbon dioxide levels caused a boom in the growth of the trees. Photosynthesis is dependent on CO2. The unexpected consequence of adding carbon to the atmosphere is that trees live longer. Oliver Phillips (co-author) also works at School of Geography. He said that “with time, growth stimulation feeds through, causing trees live faster and die earlier.” RAINFOR team monitors the Amazon canopy in Peru. Image Credit: KuoJung Chao. Recent droughts and unusually high temperatures may also play a part in the Amazon’s recent destruction. Researchers found that tree deaths have increased even though they occurred before an extreme 2005 drought. However, prolonged dry spells in recent years have resulted in the death of millions more trees. Dr. Brienen cautioned: “Regardless the cause of tree mortality increases, this study suggests that projections of an increase in carbon storage in tropical forest may not be realistic.” Climate change models which include vegetation responses predict that the Amazon will continue to store carbon as long as the carbon dioxide level continues increasing. “Our study suggests that this is not the case. Tree mortality processes are crucial in this system.” Nearly 100 scientists were involved in the project. Many of these researchers have been working in South America for many decades. Measurement of Amazon trees in Peru. Image Credit: Roelbrienen. The study was conducted by RAINFOR. This unique network is dedicated to the understanding of Amazon ecosystems. To determine whether carbon storage has changed, and if so by how much, the scientists examined 321 forest plots across the Amazon’s six million square kilometers, identified and measured more than 200,000 trees, and recorded tree deaths and births since the 1980s. Prof. Phillips said: “All across the world even intact forests are changing. Although forests are doing us great favor, we cannot rely on them for the solution to our carbon problems. To stabilize our climate, we will need to make deeper reductions in carbon emissions. Boot + et al. Nature. Publication March 19, 2015. DOI: doi: 10. 1038/nature14283.
Amazon has a 50 percent decrease in carbon absorption capacity since 1990s.
