Seeing Green in Tropical Forest Management
From Central American forests to the Amazon jungle to Andean timberlands, NC State researchers see the forests for the trees. Through internationally recognized programs and individual projects, they are working to preserve threatened species while improving forest management techniques that benefit local economies, environmental stewardship, and biological diversity.
Riding with military convoys at night through guerrilla strongholds in Guatemala and Honduras provokes less fear in Dr. Bill Dvorak than the thought of losing tree species indigenous to the countries. As director of the Camcore International Tree Conservation and Domestication Program in the College of Natural Resources (CNR), Dvorak must sometimes resort to such unusual measures to collect seeds from trees in remote areas before they are wiped out by development, disease, or infestation. Camcore scientists have harvested seeds from dozens of pine and hardwood species in the Americas, southern Africa, and Southeast Asia. The seeds are then sent to other countries with comparable climates, where they can be grown in trial plots—Dvorak calls them “zoos for trees”—to preserve
the genetic identity of the tree species.
“We’re an international Johnny Appleseed.”
Meanwhile, Dr. Erin Sills, a CNR forest economist, studies the economic tradeoffs Brazilian populations make in choosing conservation over deforestation. Communities in different parts of the Amazon rainforest have had varying degrees of success with conservation, she says. People living in the Tapajós National Forest have demonstrated that developing non-timber markets, such as rubber and ecotourism, can make forest management economically beneficial. On the other hand, dairy farmers in the western state of Rondônia have increased their standard of living by clearing large swaths of jungle for pastureland. “It often becomes a win-lose proposition,” Sills says. “Local populations win in terms of their own welfare while we lose forests globally.”
Sills says voluntary programs to promote conservation don’t produce much bang for the buck. A system in Costa Rica pays landowners to set aside chunks of forest, but Sills studied satellite data to compare those areas with nearby forests not earmarked for conservation and found only a small difference. “A lot of what the government is paying for wouldn’t have been deforested anyway,” she says, adding that her research can’t measure intangible benefits of direct payments for conservation. “The program does raise public awareness of the environmental value of forests and boosts Costa Rica’s public image as a leader in conservation policy.”
Hundreds of miles to the south, Dr. Doug Frederick, a professor of forestry and environmental resources, hopes research on Chilean forest management for watershed improvement will also benefit North Carolina timberlands. He is studying a protected area supplying water to Valdivia, a coastal city in southern Chile, to determine how best to manage the stands for timber production, water quality, and recreational use of the area. “This has vast application to millions of acres that aren’t under management,” Frederick says. “Tree farmers without comprehensive management plans tend to sell their timber to companies that want to maximize profits, not maximize the growth of the trees and protect other resources of the land. This is true for about 90 percent of North Carolina tree farmers, too.”
“People ... are pushing forests past the tipping point, making it difficult for them to recover.”
Farther north in Chile, Dr. Lee Allen is working with researchers at Universidad de Concepcíon to better understand what nutrients are needed to optimize growth of pines and hardwoods. The Forest Nutrition Cooperative (FNC) that Allen co-directs partners with forest landowners in five South American countries to improve the efficiency of tree plantations and help meet the growing world demand for timber. “We combine high tech with high touch,” he says, noting that researchers use satellites to measure the growth of tree stands and conduct dozens of workshops annually to inform timber companies and other forest landowners of their findings and best practices.
The FNC analyzes data on soil nutrients, tillage treatments, and weed control to determine how to optimize the leaf area of plantations to increase productivity. More light captured by leaves and pine needles means more photosynthesis and growth. “Everything used to be ‘spray and pray,’” Allen says. “We’ve learned soil resources change as a stand changes over time, and if we understand why they are dynamic, we can develop more targeted solutions.”
“Local populations win in terms of their own welfare while we lose forests globally.”
Understanding the interplay between the Amazon rainforest and adjacent savannas is the research focus of Dr. Bill Hoffmann, a plant ecologist in the Department of Plant Biology. Hoffmann lived in Brazil for eight years before joining NC State’s College of Agriculture and Life Sciences. The boundary between forest and savanna amounts to “a game of chicken,” he says, as tree species push the limit of their tolerance to populate marginal areas. Working in irrigated and fertilized trial plots near the capital city of Brasilia, he is trying to determine what limits the extent of tropical forests under natural circumstances in order to better predict how forests will respond to climate change and increasing pressure from humans. “People, through a variety of actions, are pushing forests past the tipping point and making it difficult for them to recover,” he says. “We need to learn more about trees so we can control the loss of forests.”