SÃO PAULO-  Trees in the northern part of the Amazon rainforest recover their capacity to absorb carbon dioxide (CO2) from the atmosphere more quickly after selective logging compared with trees in the south where the climate is less favourable, a study reports.

Published in the journal eLife last month (December 20), the research assessed the dynamics of CO2 absorption in parts of the Amazon after they had been through selective logging — a practice where only the most valuable and biggest trees are cut down and collected.

The Amazon rainforest accounts for up to 30 per cent of the total CO2 stored by forests globally. But every year, selective logging contributes to the release of a big part of this stored carbon, contributing to global warming.

These emissions are cancelled out in the medium term, thanks to the carbon dynamics of the forests themselves: the remaining trees — those not harvested — and young trees — which regenerate naturally after logging— assimilate atmospheric carbon again.

Using computer models, the researchers assessed the trees’ potential for CO2 storage, over a 10-year period, from 133 plots scattered around 13 regions of the Amazon.

They found that trees in the northern sites recovered their capacity for CO2 storage soon after logging, and they did so faster than forests of the southern Amazon.

According to the authors, the trees in the northern forests grow faster than the southern ones — and growth increases carbon storage capacity — because they have richer soil and a more humid environment.