College of Agricultural and Life Sciences
Above ↑ Like tropical forests throughout the world, the Manupali River watershed in the southern Philippines has suffered from development that brought deforestation, intensive agriculture and a degradation of water quality. The challenge, says economist Ian Coxhead (b), is to work with local communities to find better ways to use the land without requiring a group of very poor people to sacrifice their incomes.
Can This Forest Be Saved?
Getting community members involved was a key to the project’s success. Volunteers who monitored water quality quickly understood the impacts of unregulated intensive agriculture.
Much of the agricultural research focused on agroforestry techniques — raising trees on the same site as field crops or livestock to increase the total yield of products, generate short-term income, and reduce soil erosion.
Why tropical forests matter
The massive conversion of the world’s natural landscapes to agriculture and other human uses may soon begin to undermine the planet’s capacity to sustain a burgeoning human population, according to an article in the July 22, 2005 issue of Science magazine. “Short of a collision with an asteroid, land use by humans is the most significant impact on the world’s biosphere,” says Jonathan A. Foley, a UW-Madison climatologist and lead author of the article. Nearly one-third of the world’s land surface is now used for agriculture, and millions of acres of natural ecosystems are converted each year, the authors point out. Many of the agricultural practices adopted are unsustainable, they add. The article can be viewed online here.
Related Links
A tropical watershed is a 100-square-mile laboratory on sustainable land use
If you’re concerned about the fate of the world’s tropical forests, you won’t like the story of the upper Manupali basin — until you get to the ending.
For more than 40 years, the Manupali watershed — located on the southern Philippine island of Mindanao — was a good example of how unrestricted conversion of forest to farmland can cause serious environmental damage, both in the forest and far downstream.
But in the last 10 years, it has served as an example of how such damage can be mitigated, and avoided in the future.
The story starts in the 1950s, when loggers built roads into the dense forest so that they could clear-cut large tracts of timber. The roads opened once-impenetrable areas to settlement. Many of the newcomers were poor people trying to escape overpopulated lowland cities. In the uplands, they could claim and clear plots of forestland, often by burning.
The deforestation reduced wildlife habitat and biodiversity. It also curbed the forest’s ability to store rainwater, which increased the likelihood of flooding in wet seasons and decreased stream flow in dry seasons. Intensive farming on steep slopes depleted soils and caused erosion, sedimentation of streams and degradation of water quality downstream.
Poor people and poor policy
These activities were fueled both by poverty and poor public policy, explains Ian Coxhead, an economist in the College’s Department of Agricultural and Applied Economics who studies how economic and political forces affect land use decisions.
“It’s often the poorest people who are engaged in the most forest-damaging behavior,” he explains. “They operate in the most marginal agricultural areas, they tend to have short planning horizons, and they’re less concerned about long-run soil productivity and environmental considerations than wealthier people might be.”
National trade policies caused agricultural production to intensify from the 1970s through the 1990s, he adds.
“There was a switch from pasture and coffee — crops that were more sustainable because they were based on permanent ground cover — to short-term seasonal crops, especially corn and vegetables. In the Philippines, both corn and vegetables are subject to high import barriers. Farm gate prices for these goods are close to double world market prices. This run-up in domestic prices over about 20 years encouraged a major expansion of corn and vegetable production.”
The Manupali story took a turn for the better in 1994, when a team of scientists adopted the north half of the upper watershed as a laboratory to research strategies for promoting adoption of sustainable agricultural practices.
The project was part of a global research and outreach initiative, the Sustainable Agriculture and Natural Resource Management Collaborative Research Support Program (SANREM CRSP), a collaboration of U.S. land grant universities, including the UW-Madison, and other agencies. Ian Coxhead joined the Manupali project at the outset and later became director of SANREM’s work in Southeast Asia.
A vast laboratory
The study area covered 30,000 hectares — roughly 100 square miles — ranging from river flats to rolling hills to mountain slopes. The area was losing forest cover at the rate of 500 hectares per year but still included undeveloped forest. Within the area was a national park that was rich in biodiversity but threatened: Forest at its edges was being cleared by burning.
The research team was multinational and multidisciplinary, with expertise ranging from agroforestry (a farming strategy that combines agricultural and tree crops) to water conservation to economics to anthropology.
Over a 10-year period, the team’s multiple research projects focused on three broad strategies:
- Build community awareness of environmental problems
- Motivate farmers to adopt sustainable practices
- Advocate for changes in trade policies that encourage poor land use
One SANREM tenet is that land-use issues must be addressed on a landscape scale, rather than town by town. Another is that research targeted at changing land-use decisions must be participatory: local people must be involved in collecting data, interpreting findings and deciding how the findings should be applied.
“We aim to build trust at the local level,” says Coxhead. “We focus on building community-level institutions and base our research and technology-transfer strategies on those institutions.
“The challenge for the team,” he adds, “was to work with local communities to find better ways to use the land without requiring a group of very poor people to sacrifice their incomes.”
One example of this approach was how the team set out to raise awareness of water quality problems.
They care about water quality
“One of our water quality specialists helped set up volunteer water-quality monitoring groups that became key sources of our data,” Coxhead explains. “They gathered data from nine locations throughout the watershed, measuring stream flow, suspended solids and coliform bacteria count.
“They found that the farther down the watershed they went, the greater was the degradation of water quality. We linked this to the intensity of agricultural production: The farther down the watershed, the less the forest cover, the more the agricultural land use and the higher the suspended solids and coliform bacteria count.”
“The focus on water quality is the sharp end of a project like this,” he adds. “It gets people interested in the relationship between deforestation and environmental quality.”
The findings got the attention of local officials, including a reputedly pro-development municipal mayor.
“It turned out that in his own village, the coliform count was very high,” says Coxhead. “This was transforming for him. He was instrumental in inserting environmental considerations into the municipality’s natural resource management plan.”
The participatory approach was equally important in research focused on sustainable farming strategies.
“Farmers were involved in the research. Much of it was conducted on their farms. They hosted participatory assessments of those experiments. They would look at each other’s fields and talk among themselves, evaluating the worth of these measures,” Coxhead says.
Farmers were quite willing to adopt practices that proved to be economically rewarding — for example, planting marketable perennial crops in hedgerows along contour lines to stem erosion.
“There have always been a lot of upland soil conservation strips that impede erosion, but these were typically based on grasses that aren’t much use for anything else,” Coxhead says. Our agronomists experimented with crops that were good as strips and also provided extra income, such as pineapple and sunflowers.”
Measuring success
These efforts have helped stem encroachment on the borders of the national park and mitigate damage already done there. Increased fruit and timber production helped re-establish tree cover in a buffer zone around the park. Several hundred farmers installed vegetative contour strips on hilly land. Soil erosion and runoff declined, yet corn yields increased by an average of a half-ton per hectare. In the villages near the park, farmers established a network of “Landcare” groups that promoted conservation. Encroachment in the park was reduced by 95 percent.
Although the field work has been completed, it continues to bear fruit in the Manupali watershed — where communities continue to refine land-use plans and regulations — and beyond.
Some of the research findings are compiled in a book, Winning the Water War, that has helped frame the debate on issues of water scarcity and water quality in the Philippines. Coxhead hopes the research will also inform discussion on trade policies.
“We’re working with local and national agencies to try to get them to coordinate policies — to think about the spillover from trade policies to the environment. We want to get them to think about these unexpected consequences,” he says.