European forests are demonstrating signs of nearing a saturation point in a persistent carbon sink, according to a new study.
This could threaten one of the continent’s primary defences against global warming.
Due to the impact of natural disturbances, deforestation and a reducing volume of trees, the amount of carbon dioxide absorbed by Europe’s trees has been declining since 2005, the scientists reported in Nature Climate Change.
Carbon sinks are promoted as a method to counterbalance increasing emissions, and play a crucial role in the world’s carbon cycle.
At the moment, forests absorb around ten percent of Europe’s emissions from cars, power plants and factories.
In recent times, the continent’s trees have been recovering after hundreds of years of deforestation and decline in stock. The continuous carbon sink from the regrowth was anticipated for decades to come, but the early signs of a saturation point give management strategies and forest policies the need for revision according to the report.
Three signs pointed to a saturation point, the team observed.
Firstly, was the increment rate of individual tree stem volume was increasing, curbing the sink after decades of increase.
Secondly is the intensifying land use, resulting in deforestation and the subsequent carbon losses, they wrote.
Thirdly is the increase of natural disturbances such a wildfires, and consequently, carbon dioxide emissions are increasing too.
Study leader at the Netherlands’ Wageningen University and Research, Gert-Jan Nabuurs, said the saturation point might be reached by about 2030, unless governments acted now.
Meanwhile a forestry expert with Copenhagen’s European Environment Agency, Annemarie Bastrup-Birk, said the problem remains very regional, with Germany and France mainly showing the reduction in forest growth, and gains still being established elsewhere.
By 2020, the European Union aims to slice its total greenhouse gas emissions by a fifth below 1990 levels, in a bid to address and slow global warming.
In 2011, an international report on the condition of Europe’s forests found that the EUs net annual growth in living tree wood decreased from 620 million cubic metres in 2005 to 609 million cubic metres in 2010.
Image Copyright Maksim (Courtesy Wikicommons)