Gilbert Tiepolo, Conservancy forest architect
Along Brazil’s coast — home to one of the most threatened forests on Earth — conservationists have enlisted the service of some unique partners to help bring trees back to the country’s shrinking Atlantic Forest: Rodents and birds.
It seems the Brazilian agoutis — large guinea pig-like rodents — are particularly fond of the nuts that fall from the towering Araucaria trees, also know as “monkey puzzle trees.” Their appetite for these nuts means they constantly gather and bury them, scattering the trees’ seeds across acres of threatened forest floor.
When conservationists discovered the rodents’ refined tastes, they began planting lots of Araucaria trees, knowing that — with the help of their rodent partners — the trees would quickly grow and spread to create the canopy that diverse, smaller, shade-loving trees need to grow.
Along with using the agouti rodents to disperse seeds, the Conservancy’s forest architects also look to the birds.
Artificial perches are erected in areas where trees have disappeared. As birds fly across the empty lands between forested areas, they stop to rest on the perches and help spread seeds through defecation and regurgitation.
This odd coalition between humans and animals is just one of the many strategies forest architects are using as they design plans to rebuild the disappearing Atlantic Forest.
“Forests are just like a baby. You need to take care of the forest, do maintenance for one or two years to help them grow,” says Gilberto Tiepolo, a forest architect with The Nature Conservancy who is helping rebuild the Atlantic Forest in Brazil.
“You have to constantly clear the area around a seedling, water the seedlings, help protect them against competition from weeds.”
Every second, one acre of forest disappears from the planet. That adds up to more than 37 million acres of forest — equal to the size of New York State — wiped off the face of the Earth each year.
And no single tropical forest on Earth has come closer to complete destruction than Brazil’s Atlantic Forest. Once stretching across an area twice the size of Texas, only 7 percent remains today, the result of generations of uncontrolled agriculture and development.
Today, the threats continue from ranching, illegal logging, urban expansion and soy, cocoa and sugarcane production.
But the shrinking forest is home to some of the most diverse species on Earth. On fewer than two and a half acres, scientists have identified more than 450 tree species, more than are found on the entire eastern seaboard of the United States. The forest also serves as the home to:
To rebuild the Atlantic Forest, Tiepolo and his colleagues do a lot more than simply dig holes and drop in seedlings.
“We have to look at what native species grow in what area,” says Tiepolo. “Some species need more light, some need more shade. Depending on the area, you may have to create a primary layer of trees, and then you can plant the secondary layer.”
The primary layer — known as the pioneer species — are fast-growing trees that reach 50 to 80 feet high, tall enough to provide shade for the wide variety of second-tier species that will be planted, sometimes years later.
The seedlings of both these pioneer and secondary trees are grown in greenhouses by members of local communities. Once the seedlings reach the correct size, the community members work with Tiepolo and others to plant them in the ground.
This way, the project not only rebuilds the forest and regenerates biodiversity, it also helps create jobs and income for people who have lived with the forest for generations.
Once the second-tier trees reach adequate height, local community members then go to healthier, neighboring forests to scoop up mounds of soil full of seeds, ferns, moss and other biomass. The mounds of soil are then placed beneath the secondary trees to create yet a third layer of diverse forest life.
These reforested areas can then serve as “islands” of biodiversity. The goal is to allow these islands to grow and spread naturally, reconnecting to remaining forest areas and rebuilding a healthy system.
And wildlife is a critical part of that. Not only do animals rely on the forest for survival, but the forests need native wildlife to help it grow.
“We’re trying to imitate the natural regeneration process,” says Aurelio Padovezi, another forest architect working with The Nature Conservancy in Brazil. “We help out for a couple of years, nurturing the forest, helping it get strong enough to survive. We can then leave it alone and let it grow on its own.”
(April 2009)February 16, 2011
Karen Foerstel is senior writer for the Conservancy's Office of the President.