BY Barbara Fraser
IQUITOS, Peru — At a small table in a noisy, bustling market, Ana Ríos Ruiz ladles thick, yellow juice into a mug and hands it to a customer. Pocketing a few coins, she turns back to a plastic bowl filled with a yellow paste speckled with brown. “We eat a lot of aguaje here,” she said, using the local name for the fruit, which is eaten raw or turned into products ranging from juice to ice cream. “Thanks to the aguaje, I’ve been able to provide for my children.”
Aguaje is the fruit of the Mauritia flexuosa palm, which grows throughout the Peruvian Amazon in swamps known as aguajales. But the swamps are threatened by encroaching development, which can lead to the release of large amounts of greenhouse gases that contribute to global warming, according to scientist Kristell Hergoualc’h of the Forests and Environment Program at the Center for International Forestry Research (CIFOR).
Better conservation and management of these Amazonian wetlands would benefit both the climate and thousands of people like Ríos whose livelihoods depend on the fruit, she said.
Palm swamps under pressure
Peru’s palm swamps are important not just because of the aguaje fruit, but also because some contain peat, an organic layer of decomposed leaves, twigs and other plant material that accumulates under the water over thousands of years.
“Peru has the second-largest expanse of peatland in the tropics, after Indonesia, and Peruvian peatlands store considerable amounts of carbon. But if you degrade, deforest or drain them, instead of being a sink for carbon, they can become a source of carbon dioxide,” said Hergoualc’h, who is leading a CIFOR team studying Amazonian peatlands as part of the Sustainable Wetlands Adaptation and Mitigation Program (SWAMP), a collaboration with the U.S. Forest Service and the Peruvian Amazon Research Institute (Instituto de Investigaciones de la Amazonía Peruana, or IIAP).
The swamps also help purify water and provide breeding habitat for fish, while many mammals feed on the palm fruit, according to Dennis del Castillo, who heads the forest management and environmental services research program (PROBOSQUES) at IIAP in Iquitos.
Peru’s aguajales face threats from development, agriculture and even the people who harvest the fruit.
Once the palms grow so tall that their fruit hangs beyond reach, most harvesters simply chop the tree down — quicker and easier than climbing up and cutting off the hanging clumps of aguaje, del Castillo said.
Cutting the palms, combined with logging of timber species in the swamps, can change a swamp’s micro-climate, drying it out and exacerbating the degradation, Hergoualc’h said.
“If you remove tree canopy cover, more sun gets in; the air temperature, soil temperature and soil moisture change; and evaporation increases,” she said. “So you reduce the flooding conditions of the ecosystem.”
As long as the partly decomposed peat layer is underwater, the carbon in it remains trapped. If the swamp dries or drains and the peat is exposed to the air, however, decomposition is hastened, releasing large amounts of carbon dioxide, which contributes to climate change.
In various parts of the Peruvian Amazon, palm swamps have been cleared, drained and turned into rice paddies or oil palm plantations, del Castillo said.
Peru’s peatland puzzle
The SWAMP researchers hope their work will help Peruvian government officials plan more effective conservation measures for palm swamps, but various questions must be addressed first.
For one, Peru’s peatlands are a bit of a mystery. They are estimated to cover 50,000 square kilometers — an area almost as large as Costa Rica — but the real figure could be more. No one knows for certain, because no reliable inventory exists, Hergoualc’h said.
To complicate matters, not all palm swamps contain peat, and scientists are not sure which ones do, or why. Hergoualc’h is beginning the study in Peru by surveying swamps in the Loreto and Ucayali regions to select about two dozen of them — some intact and some degraded — that contain peat.
She and her colleagues will then calculate the carbon contained in the aboveground vegetation and the underwater peat layer, as well as the greenhouse gas emissions from the soil.
Those data, combined with the development of techniques for satellite monitoring of peatlands, will give policy makers more tools for complying with international treaties on climate change and monitoring for the UN-backed Reducing Emissions from Deforestation and forest Degradation (REDD+) program, she said.
They will also provide support for the development of policies to improve palm swamp conservation and management, del Castillo said. His research center is developing a slow-growing variety of aguaje palm that will make it easier for people to harvest the fruit without cutting the tree.
Meanwhile, he added, officials should encourage harvesters to climb the palms and cut off the fruit instead of felling the trees. Officials must also weigh the ecological benefits of the aguajales and peatlands against other land uses, such as farming or oil palm plantations, he said.
“We need to conserve the aguajales not just for their own sake, but because they play an extremely important ecological, economic and social role,” del Castillo said. “Policy makers and people in the private sector need to understand that conserving an aguajal may make better economic sense than planting oil palm.”
For more information on the topics discussed in this article, please contact Kristell Hergoualc’h at email@example.com.
CIFOR’s research on forests and nutrition is part of the CGIAR Program on Forests, Trees and Agroforestry. The SWAMP project is supported by funding from the U.S. Agency for International Development (USAID).