Reforesting is a good idea, but it is necessary to know where and how

Publicado em 18 outubro 2019

An article recently published in Science titled "The global tree restoration potential," presents what he calls "the most effective solution to mitigate climate change." The lead author is Jean-François Bastin, an ecologist affiliated with the Swiss Federal Institute of Technology (ETH Zurich). The article reports the results of a study in which it is estimated that there are no more than 900 million hectares worldwide.

The study has been reviewed by Joseph Veldman, a professor in Texas's A & M University's Department of Ecosystem Science and Management (US). Science published under the title "Comment on 'The global tree restoration potential.'" Its authors include William Bond, Emeritus Professor in the University of Cape Town's Department of Biological Sciences (South Africa) and considered the world's foremost expert on savanna ecology. Several Brazilian researchers also co-authored the reply, including Giselda Durigan, affiliated with the São Paulo State Forestry Institute's Ecology and Hydrology Laboratory.

"The plan proposed by Bastin et al is based on flawed calculations and is actually a threat to The planet's savannas, meadows and water resources, "Durigan said.

Bastin and collaborators made" extremely basic mistakes, "they added, among the reforestable areas of Yellowstone National Park, Los Llanos, Venezuela (considered one of the world's most important ecosystems), and the Cerrado in Brazil.

The Cerrado is the world's most biodiverse tropical savanna and gives rise to some of Brazil's major rivers, such as the Xingu, Tocantins, Araguaia, Sao Francisco, Parnaiba, Gurupi , Jequitinhonha, Paraná and Paraguay, among others.

"Unfortunately, the key premises used in the study and the calculations performed by the authors are incorrect, resulting in af ivefold overestimation of the potential for forest planting to capture carbon and mitigate climate change, "Durigan said. "Furthermore, Bastin et al., In the map of the country with potential for reforestation many areas in which trees would reduce surface albedo and intensify global warming the world. "

Albedo is the amount of solar energy reflected by Earth's surface. The darker the surface, the less sunlight it reflects, and the more it absorbs. The solar energy absorber is converted into heat. Forests absorb more solar energy than open grassland.

Moreover, the biomass impairs water production in river basins has been researched trees consume large amounts of water to survive.

In sum, reforestation is an excellent idea, but it is necessary to know where and how to implement it.

"Bastin and collaborators focused too narrowly on the carbon balance, and to make matters worse, they miscalculated by underestimating the carbon trapped in the ground under open vegetation, while overestimating the carbon content, "Durigan said.

" The areas have been degraded, but have been degraded

Grasslands and savannas are natural formations but are treated as degraded areas in a landlocked state the article. "They overlook the fact that climate is not the only natural variable affecting biomass in ecosystems." in which they have been maintained for millions of years by natural fire and herbivory regimes, "she said.

In Durigan's Opinion, the article by Bastin et al. drew exceptional attention because it pleases large corporations and countries that benefit from fossil fuel burning to drive their economies. "If the world believes the arguments in the article, the pressure for corporations to reduce fossil fuel emissions will be weakened," she said.

When tree planting damages ecosystems

More information:
Joseph W. Veldman et al. Comment on "The global tree restoration potential," Science (2019). DOI: 10.1126 / science.aay7976

Citation :

Reforesting is a good idea, but it is necessary to know where and how (2019, October 18) retrieved 18 October 2019 from