The Ecological Society of America, the Nation’s leading body of professional ecological scientists (of which I am a proud member), has released a position statement on biofuels sustainability. The full text is here. Because these are highly important issues and the ESA’s position is authoritative and well stated, I quote much of it here verbatim. The paper makes three central points, of which the second is of particular interest to natural patriotism:
“1. SYSTEMS THINKING. A systems approach is crucial to assess the energy yield, carbon neutrality, and the full impact of biofuel production on downstream and downwind ecosystems. It should take into account all of the flows, controls, and storage of materials and energy.
2. CONSERVATION OF ECOSYSTEM SERVICES. A focus on ecosystem services will provide the foundation necessary for win-win scenarios. It is easy to design systems for maximum crop yields; over a century of agronomic research has shown that this can be done very successfully. Managing for other ecosystem services also provided by agricultural landscapes is less common but equally necessary. Lower yields from an unfertilized native prairie, for example, may be acceptable in light of the other benefits provided by native plants in an agricultural landscape. These include:
- A complete and closed cycling of nutrients;
- Minimized flooding and increased groundwater recharge;
- Enhanced carbon sequestration in the soil because tilling would be unnecessary;
- Fewer pests because habitat for insects and birds that prey on them is left intact;
- Genetic diversity;
- Reduced nitrogen and phosphorus runoff because no fertilizer is needed;
- Reduced soil erosion due to continuous soil cover;
- Reduced nitrous oxide production; and
- Pollinator habitat and resources.
These benefits, in turn, would help ensure ecosystem services such as better water and air quality, crop pollination, flood mitigation, runoff reduction, and food and fiber production. [Note: For a bit more detail on the potential advantages of diverse native prairie plants as a biofuel crop, see my earlier post here]
3. SCALE ALIGNMENT. Explicit consideration of scale in policy and management is necessary to achieve sustainability goals.”
Details can be found in the original document linked above. With specific regard to the current mania for corn ethanol in the USA, the ESA has this to say:
“The current focus on ethanol from corn illustrates the risks of exploiting a single source of biomass for biofuel production. A growing percentage of the U.S. corn harvest – 18 percent in 2006 – is directed towards grain ethanol production. This has not only resulted in record-high corn prices, it has produced strong incentives for continuously-grown corn, higher-than-optimal use of nitrogen fertilizers, the early return of land in conservation programs to production, and the conversion of marginal lands to high-intensity cropping. All of these changes exacerbate well-known environmental problems associated with intensive agriculture:
- Continuously-grown corn is more susceptible to insect damage and allows weeds to become more persistent, requiring more insecticides and herbicides.
- Nitrogen fertilizer is the principal contributor to nitrogen pollution of groundwater, surface waters, and coastal zones, and a major source of the greenhouse gas nitrous oxide.
- Placing previously fallow land enrolled in conservation programs back into production reduces wildlife diversity, requires irrigation, and releases carbon dioxide.
- Converting marginal lands to agriculture or farming them more intensively creates new sources of agricultural pollution and, in many cases, disproportionately increases nutrient loss and soil erosion; many of these lands are marginal to begin with because they are on sloping, sandy, or wet soils particularly susceptible to soil and nutrient loss.”
Other position papers from the ESA, on topics ranging from the Endangered Species Act, to GMOs, to forest fire management, to sustainable water use, to links between biodiversity and ecosystem services, can be found here.