Five years ago, the Félix-Houphouët-Boigny University (in Ivory Coast) and CIRAD (the French organization for agricultural research and international cooperation for the sustainable development of tropical and Mediterranean regions), together started the program “Dynamics of the restoration of ecosystem services ”.
And, after five years of work, the program has resulted in a recently published article in Science , which concerns tropical forests around the world.
Since the 1960s, the Ivory Coast has exploited cocoa in large areas. Originally a plant of South American origin, the cacao tree has been exploited in Africa in full sun, in order to increase and improve its performance.
Thus, farmers have cut down large trees and deforested nearly 10 million hectares in just over half a century. Subjected to this intense regime, the soils, suddenly bare, were washed away by the rains , for which the farmers were forced to look for other fields for this commercial crop to move from western Côte d’Ivoire to the east, leaving thousands of hectares fallow .
What happened in them? This was the question asked by researchers from the Félix-Houphouët-Boigny University and CIRAD, in France.
As Bruno Hérault, a researcher at the French CIRAD pointed out, “we have seen that in these abandoned lands, the forest has regained its rights”. But scientists had yet to develop a methodology to estimate recovery trajectories between secondary forests and ecosystems before logging for agriculture and the speed of this rebuilding.
An approach that, according to the experts, would refer to chronosequences . Thus, the researchers focused on the history of landscapes based on the testimonies of the peasants.
Through collisions and discussions, they were able to reconstruct the evolution of the place, from the first agricultural plantation to the abandonment, passing through the agricultural exploitation phase. A chronology that, incidentally, was confirmed by satellite images.
They analyzed the recovery patterns of forest attributes (including features and elements of sleep, structure, diversity, and plant functioning) at 77 secondary forest sites throughout the Americas and West Africa.
And they discovered what the scientists themselves affirm in their study: “although deforestation is rampant in the tropics, forests have a great capacity to regrow on abandoned lands .”
Specifically, they found that different attributes could be recovered at different rates, with the soil recovering in less than a decade , while biomass and species diversity did so in just over a century .
They point out that these “secondary” forests may end up playing an even greater role in biodiversity conservation , landscape restoration and climate change mitigation.
Therefore, in their work the authors discuss how these findings could be applied in efforts to promote forest restoration.
