Thursday, May 3, 2012

Tree-planting schemes sprout across South America

Alertnet / Ana Belluscio, March 27,2012

Children at the elementary school in El Trapiche village in Argentina’s San Luis province have been working out the amount of carbon dioxide emitted by generation of electricity used in local homes, and planting trees to suck up an equivalent amount of the greenhouse gas.

Principal Isabel Lagos says the “Zero Balance” programme – developed by researchers at the local University of La Punta - has helped her pupils learn about environmental conservation and the need to reduce the planet-warming emissions that are driving climate change.

“The whole school participated - even young children,” she explains, “and they started to protect trees, becoming conscious of their importance.”

Six-year-old Wendi and nine-year-old Camila, sisters and pupils at the school, recount how they went from house to house asking people about their energy consumption.

“I planted five trees, and after the second survey, I planted some more,” says Camila.

According to programme coordinator Victoria Marini, the aim is to “teach children about climate change, energy efficiency, afforestation and environmental education through the use of technology”.

Students learn how to achieve a “zero balance” in emissions, by calculating the amount of carbon dioxide released by the use of power in their neighborhoods, then using an online tool to work out the number of trees they must plant to offset the emissions.

Since the programme was launched in December 2008, 200,000 trees have been planted in 22 towns across the central province of San Luis. Almost 6,000 children have taken part, and researchers hope that number will have risen to 50,000 by 2014.

And it’s not only children who are learning.

“Even adults (participate), by walking their children from house to house to conduct the survey,” says head teacher Lagos.

On going deforestation

Initiatives to plant new trees and restore forests are being launched across South America - both to repair the damage done to huge swathes of land cleared for farming, and to promote carbon storage in vegetation, which helps mitigate climate change.

But experts caution they must not be regarded as a substitute for greater efforts to prevent forests being cut down in the first place.

According to the 2011 State of the World’s Forests report from the U.N. Food and Agriculture Organization (FAO), South America’s deforestation rate has slowed and has remained stable in percentage terms since 1990.

But forest area in Central and South America has continued to shrink over the last two decades, mainly because of the conversion of forests to farmland – a problem expected to worsen in coming decades as demand for food grows worldwide.

Latin America – home to the world’s largest tropical forest, the Amazon - holds 57 percent of the world’s primary forests, the report notes. But scientists say forests that are lost to logging or converted into farmland are unlikely to be fully replaced once cut down.

“Some environments, such as the jungle in Misiones and Chaco (in Argentina), or the Yungas (humid forests) in the north, are so complex that they are impossible to restore,” says Carlos Fernández Balboa, an environmental education coordinator with the Fundación Vida Silvestre Argentina, a local partner of the World Wildlife Fund (WWF) that works towards sustainable development.

Whether led by states or non-governmental organisations, reforestation programmes aim to resurrect, at least to some degree, forest ecosystems affected by logging.

Protecting and planting trees can also play an important role in community development and local economies, experts say.

Fernanda Peixoto, a Brazil field representative for Trees for the Future, an organisation that works to restore degraded land through tree-planting and sustainable farming, runs workshops to explain the benefits of trees for individual households.

The group provides training and seedlings to communities in the southern Brazilian state of São Paulo, introducing agroforestry techniques to settlements generally made up of one big farm divided among many low-income families.

Since 2009, the communities Peixoto has worked with have planted 450,000 trees.

“We also show people why it matters," she says. "They need to protect their (agricultural) production with windbreaks, and they need shelter for their cows.”

Weighing up benefits

While planting trees is widely seen as a positive activity for people and the environment, some researchers say studies are needed to determine how many new trees a region can take without upsetting its natural equilibrium.

Others query the different methodologies used to quantify the environmental benefits of reforestation, including the volume of carbon emissions they are expected to reduce, and how long those benefits will last.

Another factor to consider is the type of tree that is planted. “It is not the same to reforest with native species as with exotic,” says Fernández Balboa of the Fundación Vida Silvestre Argentina. Exotic species, for example, may have different water requirements than indigenous trees.

The economic benefits of various types of reforestation also need to be analysed. Exotic species, for instance, often grow faster and produce more wood.

“If we see the problem from an environmental point of view, native (trees) are better. But if we look it from the economic point of view, exotic wins," says Marcelo Nosetto, a researcher at Argentina’s National Scientific and Technical Research Council (CONICET).

Peixoto explains that her project in Brazil focuses on replanting “productive” trees with particular features, such as rapid growth and small leaves that don’t cast too much shade, leaving the ground below them available for agriculture.

Meanwhile, Marini and her “Zero Balance” team in San Luis work both with native species, such as carob trees and caldén, and exotic species adapted to the arid ecosystem, including aguaribay and acacia.

But many experts believe reforestation and afforestation should be seen as a palliative remedy rather than a solution to the problem of deforestation.

For Fernández Balboa, protecting existing forest areas is essential.

"Education and awareness on the benefits of reforestation is great - a good campaign including native species that involves schools or government agencies is fantastic,” he says.

But once a forest is lost, returning it to its former state - even with reforestation programmes - is close to impossible, he says.

“It won’t have the same complexity or various strata as the original forest, since that takes hundreds of years to develop,” he explains.