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Ecology

Green areas multiplied

Plan increases the value of secondary vegetation to expand the Atlantic forest area

EDUARDO CESARLess than perfect forests that were once looked down on have become ecologically and economically valuable. Secondary vegetation, so-called to differentiate it from primary vegetation, which retains the structure and diversity of species in the original forest, is now seen as one of the options for an ambitious plan to expand the Atlantic forest. At the beginning of April in São Paulo, representatives from non-governmental organizations, companies and universities announced the Pact for the Restoration of the Atlantic Forest, the target of which is to recuperate over 15 million hectares of forest by 2050, an average of 300,000 to 400,000 hectares a year (1 hectare is the equivalent of 10,000 sq m, approximately the same size as a soccer field). If it manages to get hold of the US$ 15 billion necessary to fund this work and the support of thousands of rural land owners who own most of the fragments of Atlantic forest, this plan could triple the current area of the forest which is today preserved in conservation units or parks administered by public bodies.

“Of the 15 million hectares to be restored 8 million is low productivity pasture”, says Ricardo Rodrigues, coordinator of the team that prepared the restoration techniques that will be adopted under the pact, based on his work as the head of the Forest Restoration Laboratory (Lerf) of the Luiz de Queiroz Superior School of Agriculture (Esalq) of the University of São Paulo (USP) in Piracicaba, up-state Sao Paulo. “If we remove the cattle and give incentives for growing forests rural land owners could earn three or four times more than they do with livestock farming, or even more if we add environmental services, like carbon credits.”

The argument for expanding the forest is now economic. “We have to create an Atlantic forest economy”, states Miguel Calmon, coordinator of the coordinating council of the pact that has already been signed by 50 institutions, including federal government organs, like the Ministry of the Environment and the state governments of Rio de Janeiro, São Paulo and Espírito Santo. “The economy that destroyed the forest is now going to help restore it”, Calmon believes.

Today the fragments of secondary vegetation in different stages of growth (most on private property) occupy an area that corresponds to almost double the area of primary Atlantic forest. These areas, even more  than abandoned pasture where the vegetation is generally poor, could be enriched by local species and linked to larger fragments at a lower cost than restoring land with no vegetation, according to the methodology of the team from Esalq-USP (see Pesquisa FAPESP 144, February 2008). Recognized last year by the Ford Environmental Conservation Prize, this approach helped replace 4600 hectares of river-bank forest at paper and pulp company properties in Rio Grande do Sul, Bahia and Paraná, on sugar cane farms in São Paulo, coffee farms in Minas, soybean farms in Pará and cattle farms in São Paulo, Mato Grosso and Mato Grosso do Sul.

Book and map
If it is adopted by rural landowners and extended to the whole of the country by means of the pact, this technique could double the area with this type of vegetation in Minas Gerais and Espírito Santo, increase it by 50% in São Paulo and almost quadruple it in Alagoas and Pernambuco, according to the national survey that formed the basis of the pact’s targets (the 256 page book with the theories of the pact and the map of the restoration areas in Brasil can be found at www.pactomataatlantica.org.br).

Just complying with the law could expand the Atlantic forest a lot, Calmon remembers. He recognizes that the problem is that rural landowners generally do not like to leave 20% of their land to native vegetation, the so-called legal reserve, but are less resistant to preserving and restoring forest along the riverbanks, which is also obligatory by law. “Rural producers know that riverbank vegetation is important”, he says, because it preserves rivers and avoids soil erosion.  Rodrigues adds: “Few people know that the legal reserve can be used to produce wood, honey, fruit and other forest products”.

Regardless of the advances of the pact, the area of Atlantic forest has grown as a result of improvements in mediation techniques and it is no longer limited to the 7% of the area  once covered by this type of vegetation, at the time the European colonizers arrived in Brazil. This number has been used over the last 15 years and considered only the biggest and best preserved blocks. Now, depending on the criteria adopted, it can go from 17% to 27%. If smaller well preserved fragments are also considered the area of Atlantic forest can reach 17%, according to the calculations of teams from the Biology Institute of  USP, from the National Space Research Institute (Inpe) and from SOS Mata Atlântica, as recently published in the journal, Biological Conservation.

Adding secondary vegetation at a medium to advanced stage of growth to primary vegetation the total may be as much as 20% of the original area, according to a survey by the Ministry of the Environment (MMA) published in December 2006. “This figure does not mean that we’ve conserved 20% of the biodiversity of the Atlantic forest, but a vegetation cover of 20% in areas that could be forest and that need to be accompanied and monitored”, observes Carla Madureira, a professor from the Federal University of Rio de Janeiro (UFRJ), who coordinated this survey.

On a more detailed scale, which also considers the islands – or enclaves – of caatinga, cerrado, high altitude fields, swampland, mangrove swamps and forest strips along rivers and the seashore, the total area of Atlantic forest may be as much as 27% of what it was in 1500. “The bigger the scale the bigger the detail and the more forest we can see”, comments Carla. In the Amazon the opposite occurs: the detail reduces the area of native vegetation because clearings appear caused by settlements or mining in the middle of the forest. “Therefore”, she says, “before getting into a war of numbers we must consider what we are actually seeing”.