Study finds modern agriculture could foster, not degrade, biodiversity.

Farmers can play a key role in preserving the world's biodiversity, and in many cases farmland can serve to protect rather than destroy wildlife habitat, according to a new report by the Swiss-based World Conservation Union (IUCN) and the Washington DC-based agriculture group Future Harvest. "As currently practiced in much of the world," finds the study, "agriculture represents a profound threat to wild biodiversity."

Because farmland covers a huge share of the Earth's terrestrial surface and is most often located in the fertile areas that also maintain the most biological diversity, incorporating conservation strategies into agricultural practices will be essential to preserving wildlife habitat. Around the world, farming is already encroaching on protected wildlife habitat: half of the world's 17,229 major protected parks, reserves, and wildlife refuges have some form of agriculture going on within their borders. About one-fifth of the total area of protected areas is "heavily" used for agriculture, estimates the study.

Because hunger is often acute in the same areas, farm practices will have to meet the double burden of stewarding biodiversity and providing enough income and food, according to the report. At least 16 of the world's 25 biodiversity hotspots--the most species-rich regions--also have very high rates of malnutrition. These 16 hotspots alone are home to one-quarter of all undernourished people in the developing world. And in such countries as Mexico, Guatemala, Brazil, Peru, Ecuador, China, Indonesia, and Vietnam, malnutrition rates are much higher in biodiversity hotspots than in the country as a whole.

"Many people believe that biodiversity can be preserved simply by fencing it off," said IUCN scientist Jeffrey McNeely, a co-author of the study. "Our report shows that agriculture and biodiversity are inextricably linked, and to avert widespread extinctions and feed the world, we must integrate biodiversity preservation into all landscapes--from grazing lands to coffee plantations to rice paddies."

The authors detail several dozen case studies of ongoing "ecoagriculture" practices around the world. For example, in the Philippines and Indonesia, fishing communities have created "no-take" reserves where fishing is banned to provide a breeding sanctuary where overharvested fish populations can recover. A survey of these reserves found that after three years fish number, size, and diversity in the surrounding area all increased dramatically. In another case, the conversion of wetlands to rice fields in California's Sacramento and San Joaquin valleys has eliminated habit for endangered songbirds, ducks, and cranes. By flooding their fields during the fallow season, farmers created a "wetlands-like" haven for many bird species, without reducing profits.

Based on these and other examples, the article suggests six general strategies that farmers can adopt to protect wildlife without compromising farm productivity: boost production on existing farmland to reduce the need to bring wild areas under the plow; create habitat on farms for wildlife, including windbreaks, hedgerows, and other types of corridors; integrate trees and other perennials into farmscapes; reduce agrochemical use, including pesticides, herbicides, and other farm pollution; improve farmer knowledge of surrounding natural resources; and create wildlife-friendly areas near farms. In many cases, these strategies will boost farm production. More wildlife areas close to a farm mean more insects will be on hand to pollinate crops, for example. And protecting nearby forests will help replenish groundwater supplies.

The study proposes increasing the amount of collaboration between ecologists and agricultural scientists. Agricultural researchers, the report states, "have not pursued biodiversity preservation aggressively." At the same time, institutions doing ecological research "have remained focused on non-agricultural ecosystems."

In a related study, published in the April 13, 2001 issue of Science, a team of scientists headed by University of Minnesota ecologist David Tilman concluded that continued expansion of the industrial farming model over the next few decades "has the potential to have massive, irreversible environmental impacts," that may rival the effects of climate change. The authors extrapolated past trends in land, irrigation, and agrochemical use--assuming a human population that is wealthier and 50 percent larger than today. The report concludes that at current rates in 50 years there would be a 2.4- to 2.7-fold increase in nitrogen- and phosphorus-driven eutrophication of terrestrial, freshwater, and near-shore marine ecosystems, seriously degrading biodiversity and fishery yields. The study also concluded that, "should trends continue, by 2050, humans and other organisms in natural and managed ecosystems would be exposed to markedly elevated levels of pesticides."

The authors emphasize that "our forecasts are not predictions, but rather are estimates of environmental impacts should agriculture continue on the trajectories of the past 35 or more years." Pointing to widespread advances in ecological farming techniques, the authors warn that the food system "must follow new trajectories if the problems we have identified are