Director Rob Magnien Discusses the Challenges of Using Biofuels to Produce Energy
Robert Magnien, Ph.D. is a director at NCCOS in the National Oceanic and Atmospheric Administration. His office has led NOAA’s involvement with the Mississippi River/Gulf of Mexico Watershed Nutrient Hypoxia Task Force, the goal of which is to reduce the current “dead zone” in the northern Gulf of Mexico to less than 5,000 square kilometers by 2015. Current scientific evidence indicates that achieving that goal will require reducing nitrogen and phosphorous inputs by at least 45 percent.
That project is the largest interagency ecosystem management effort in the country seeking to address nutrient pollution threats. Because of the significant risks posed by this and other hypoxic zones in the U.S., Congress passed the Harmful Algal Bloom and Hypoxia Research and Control Act in 1998. That mandate supports NOAA’s longstanding and dedicated research to provide the necessary understanding and predictive tools to manage what is typically referred to as the largest “dead zone” in North America.
In this conversation Magnien discusses the potential impacts of expanding the use of corn–derived biofuels as part of the nation’s drive toward increased energy self–sufficiency.
There’s been a great deal of talk in the media and elsewhere in recent months about efforts to increase our use of biofuels such as corn–derived ethanol. It seems that over the few most recent months, what some saw as perhaps a premature rush to biofuels has raised concerns about unintended consequences. What are the scientific experts you and your office deal with telling us about likely implications for our nation’s waterways? And is their message getting through?
RM: For some time now, there has been a real sense of alarm in the water quality and coastal resource communities about the changes to agriculture that will be brought about by the increased demand for corn as a result of its use in biofuel production.
Experts in agriculture have called what we’ve been witnessing one of the quickest and most dramatic changes ever in the nation’s agricultural landscape. Virtually overnight, the price of corn has almost doubled, and this is having profound effects on agricultural practices, including changes in crop rotations, use of marginal or retired lands, and increases in fertilizer application.
Just a year or so ago, in discussions of biofuels, one almost never heard about the consequences of increased corn production on water and habitat quality. Now there is much greater awareness among those who are close to these issues. In some popular media news reports and in advertising campaigns, corn–based ethanol is generally portrayed as something of a silver–bullet solution to our energy independence challenges, an environmentally–friendly alternative to fossil fuels. What is perhaps too often going unsaid is that there may also be some negative consequences, such as increased nutrient pollution.
How will increased corn production lead to more nutrient runoff, and why is this a particular concern?
RM: It is well established that the most pervasive, widespread, and damaging pollutants affecting water and habitat quality in our nation’s rivers, lakes, estuaries and coasts are nutrients. It’s clear too that the largest single contributors nationwide to nutrient pollution are agricultural practices.
So when a dramatic increase occurs in acreage devoted to corn—which has the highest nutrient loss rate among major crops—it will inevitably lead to a higher loading of nutrients to our waterways.
Nutrient pollution leads to multiple adverse impacts on water, habitat quality, and on human health, including hypoxia or low–oxygen conditions, harmful algal blooms (or HABs), loss of important and beneficial seagrass beds, and toxicity in water supplies.
Many management agencies at the federal, state and local level have been attacking these problems for several decades. And it’s important to point out that considerable progress has been made on point sources of pollution, such as wastewater treatment plants and industrial discharges. But much less demonstrable progress has been made on nonpoint sources such as run–off from developed and agricultural lands. The dramatic increase in corn production threatens to erase and overwhelm the modest gains that have been made in recent years in reducing agricultural pollution reaching waterways.
Has research sponsored by your program turned up specific examples of cause and effect, for instance, that might occur if the nation’s farmers were to significantly increase corn production in order to help meet needs for alternative fuels?
RM: Research by our program and by others has repeatedly demonstrated the link between increases in nutrient pollution and hypoxic areas—often referred to as “dead zones”—in susceptible bodies of water such as the northern Gulf of Mexico and Chesapeake Bay. While not always in a linear relationship, algal production will increase and hypoxia will worsen should nutrient loadings increase in these systems, whether as a result of changing agricultural practices or other sources.
We also have devoted considerable research to understanding the link between nutrient pollution and harmful algal blooms. While no obvious link is demonstrable in all cases, there are numerous HAB problems that are either caused or exacerbated by nutrient pollution. Examples include blue–green algal blooms in fresh water, which cause toxicity and aesthetic problems; macro algal blooms that smother bottom habitat including corals; and high biomass blooms that deplete oxygen in critical near–shore shallow habitats, along, of course, with the better–known and more persistent hypoxic zones in deep waters.
Is your research pointing to ways that we can both reduce our dependence on unstable foreign fuel supplies and take advantage of the strategic and economic importance of alternative fuels? Is there some refocusing of research priorities that might be called for to address these apparently conflicting objectives?
RM: There are alternative fuel options that either exist now or are under development that would potentially be less damaging to our coastal environment.
One directly related to biofuels production is the use of cellulosic feedstocks such as perennial grasses, wood, or other plant material. Existing industrial processes which convert cellulose to sugars, which are then fermented to ethanol, have significant inefficiencies. Those inefficiencies for now are limiting their widespread implementation. However, it is widely believed that this technological barrier will be overcome in five to 10 years and lead to a highly cost–effective method for ethanol production. If this were to happen, nutrient pollution could actually go down as more environmentally friendly ways of producing biomass for ethanol production are implemented.
But, in the short–term, most attention is focused on corn since this is a conventional crop with well–developed production, transport, and storage methods. The Department of Energy and other federal agencies are supporting research on methods to utilize cellulosic feedstocks. Biotechnology companies also appear to be very interested in finding a solution to this challenge and perhaps other ways of using organisms to capture energy from the sun.
Much attention and research effort has been directed over the past 15 years at the hypoxia problem in the Gulf of Mexico. It appears to some that progress made in this area could be jeopardized or threatened by what some might call “a rush to ethanol” without full consideration of potential impacts. What is your research specifically showing relative to the Gulf’s hypoxia problems?
RM: Essentially all of the research findings and model predictions show that there is a positive relationship between increased nutrient loadings to the Gulf of Mexico and a larger hypoxic area in the northern Gulf. So, it’s pretty clear that reducing the size of the hypoxic zone will require nutrient reduction and that any increase in loadings threatens to increase the area affected by hypoxia.
Are there cropping strategies that can specifically minimize the impact of increased biofuels production?
RM: Best management practices such as minimum and no–till clearly offer many advantages, including reduced erosion, higher levels of soil carbon, less fuel and labor expended, and higher overall soil quality.
If the use of cellulosic feedstocks becomes practical and perennial grasses, rather than just corn, becomes a significant proportion of the crop for producing ethanol, a dramatic decrease in nutrient and sediment runoff could be expected. The solid root mat of perennials that is left in tact year after year absorbs nutrients and holds soil much more efficiently than typical row crops. As a result, the nutrient loss from these crops is a fraction of what it is for crops that require active cultivation techniques and heavy fertilizer application.
Q: When you consider what it takes to produce fuels from biological feedstocks such as grass, poplar trees or cornstalks, do even cellulosic fuels have a downside?
While some cellulosic feedstocks may have impacts relative to displacement of a natural forested landscape, they generally have much less of an impact on water quality than crops requiring intensive cultivation and heavy fertilizer application. The process of manufacturing ethanol from any feedstock, however, requires water, and this may become a problem in areas where water is scarce or during droughts.
Perhaps what our discussion most clearly illustrates is just how inter–connected and inter–dependent our ecosystems are, and how careful we must always be in considering the potential adverse impacts of actions taken for entirely good reasons. It seems clear that as we consider further use of biofuels in our efforts to increase our nation’s energy sufficiency and to reduce emissions of carbon dioxide and other greenhouse gases, we’re going to need to carefully consider potential adverse impacts that could end up reversing progress in other areas.
The core of our research efforts in this area involves embracing that wider ecosystem view and trying to avoid unintended and undesirable outcomes by developing predictive capabilities of use to managers. In that way, we can we strive both to increase our independence from unstable foreign energy supplies and also maintain our progress in protecting water quality, public health, and our invaluable coastal resources.