The United States lacks the policies needed to ensure that cellulosic biofuel production will not cause environmental harm, says a distinguished group of international scientists. The paper, published in the October 3rd issue of the journal Science, urges decision makers to adopt standards and incentives that will help ensure that future production efforts are sustainable, both energetically and environmentally.

Because the cellulosic biofuel industry is young, policymakers have the opportunity to implement science-based standards before large scale crop production begins. Early preventative polices could play a major role in minimizing the unintentional side effects of large-scale crop production, such as fertilizer and pesticide pollution, soil erosion, invasive species spread, the fouling of waterways, and species loss.

Dr. Kathleen Weathers, an ecosystem scientist at the Cary Institute of Ecosystem Studies and one of the paper's authors, comments, "Society is in a race to find renewable sources of carbon-neutral energy. Cellulose-based biofuels hold promise, but we need to proceed cautiously and with an eye toward minimizing long-term ecological impacts. Without a sound plan, we could wind up doing more environmental harm than good."

Grain-based ethanol has already served as a lesson in the perils of embracing energy solutions before their environmental effects are understood. Most of the commercial ethanol produced in the United States is made from corn. When large parts of the landscape are converted to such resource-intensive, monoculture grain crops, as is the current model, the scientific consensus is that the environment suffers.

Moving forward, if cellulosic ethanol is to emerge as a feasible source of renewable energy, a vast amount of land will need to be used for its production. This land conversion - estimated to be as large as the amount of land in row-crops today - will change the face of the global landscape. Production standards and incentive programs could help minimize negative impacts and, in many cases, help farmers choose crops that provide valuable ecosystem services.

Weathers notes, "There is the real potential for science to inform sustainable cellulosic crop strategies; it's about picking the right plant, or assemblage of plants, for a given landscape and managing crops in a minimally invasive way." No-till farming can slow erosion and enrich soil; cover crops can sequester soil carbon and minimize nutrient run-off; and buffers can support beneficial insects such as pollinators.

But this won't happen without making environmentally sustainable growing practices widely available and establishing incentives to farmers that adopt the techniques. The authors stress that as the technology to make cellulosic biofuels improves, and efforts become commercialized, both industry and legislators must adopt policies that reward sustainable crop production.

This is one of the first times such a large and diverse group of internationally recognized scientists have spoken with one voice on the issue. The 23* authors - some of the world's top ecologists, agronomists, conservation biologists and economists - encompass diverse backgrounds and professional experiences.

Weathers concludes, "Incentives, such as substantial subsidies for cellulosic ethanol production, could send us hurtling down an environmentally tenuous path. I hope decision makers heed our recommendations. They emerged from a collaborative effort that cut across disciplines and ideologies, and we came to a strong scientific consensus."

(Science Daily, 10/10/2008)