A study carried out by an international team of researchers — including scientists from the National Institute for Space Research (INPE) — showed that tropical forests degraded by human activities have not managed to regenerate properly, undermining their potential to remove carbon from the atmosphere.
Great allies of humanity in the fight against global warming, tropical forests store large amounts of carbon in their trees. At least, that’s how it should be. Research published today (15th) in the journal Nature reveals that this potential is being undermined in areas that have already suffered deforestation and are regenerating.
When a newly deforested forest area begins to recover, it assumes a stage that specialists call initial regeneration. As the first plant species develop and others begin to occupy the land, it becomes a secondary forest. The process requires not only time, but also that the area is not disturbed again.
With about 20 years of regeneration, a secondary forest already has 80% of the original species, according to data from the University of Wageningen, in the Netherlands. Five decades after cutting, the area reaches a stage very similar to the native forest, also called primary forest.
The researchers, for the first time, estimated the global potential for carbon uptake by forests in the regeneration stage. The results show that, although it is important to keep the native forests standing, it is necessary to guarantee that the already degraded areas have adequate time to recover.
These areas have removed at least 107 million metric tons of carbon from the atmosphere annually. The amount, however, is equivalent to 26% of what is emitted through deforestation.
To reach these conclusions, the study used satellite data to analyze forests in the Amazon, Africa and Borneo, in Southeast Asia. The main sources of disturbance identified in the regeneration areas were fires and the selective extraction of trees whose wood has great commercial value.
Luiz Aragão, director of the Earth Observation and Geoinformatics division at INPE, says that “focusing on the protection and restoration of degraded forests is an efficient solution to build robust mechanisms for sustainable development in tropical countries.” The researchers highlight not only the environmental role of the areas, but also the socioeconomic benefit that forest regeneration can provide to local populations.
