New comprehensive research shows that the Renewable Fuel Standard has had numerous environmentally devastating effects — accelerating climate change, increasing nitrous oxide that leads to dead zones, destroying monarch habitats, increasing crop prices, and depleting western aquifers.
The new research by the University of California-Davis, Kansas State University, and University of Wisconsin, sought to provide data to quantify environmental changes that have followed expansion of the Renewable Fuel Standard in 2007.
The annual emissions from RFS-induced land conversion were equivalent to 5.8 million cars on the road, or 7 coal-fired power plants, according to the National Wildlife Federation, citing the research.
“In the eight years following expansion of the RFS in 2007, the policy bolstered the amount of corn planted on existing cropland each year by an average of 6.9 million acres, or 8.2 percent more than would have occurred without the RFS,” the summary noted.
During the same time span, the RFS also stimulated an increase in total cropland area of 2.8 million acres, which accounts for 43 percent of the total cropland area change observed during the period.
“These changes have wide ranging environmental impacts,” the summary stated. “For example, intensified corn production on existing cropland contributed to an estimated 319,000 metric tons/year of additional nitrogen applications and associated emissions of 3.1 million metric tons of carbon dioxide equivalents per year.”
In addition, the RFS-related changes to cropland extent committed carbon emissions of 27.1 metric tons per year from land use change and increased annual consumptive water use by 16.7 billion gallons per year, the summary noted.
Crops grown on new croplands due to the RFS used 10.5 billion gallons per year of more water from any source than the grasslands and natural vegetation they replaced.
“In 2012 – in the midst of a devastating drought – some ethanol refineries in arid states [like] Arizona, Idaho, and Wyoming were producing ethanol from corn that had required more than 2,000 gallons of irrigated water for each gallon of ethanol produced,” said the NWF website.
Forty-one federally listed threatened or endangered species had at least 10 acres of land converted to crop production between 2008 and 2016 within the boundaries of their “critical habitat” as designated by the U.S. Fish and Wildlife Service.
Sixteen aquatic threatened or endangered species saw conversion of at least 5 percent of the land in watersheds surrounding their critical habitat, increasing the risk of farm runoff. A total of 107 species saw some conversion in their watersheds.
The increased frequency of corn planted on existing cropland led to greater application of nitrogen (N) on the landscape to grow crops. We estimate an additional 319,000 metric tons of N from either synthetic fertilizer or manure was applied to existing croplands on average each year between 2008 and 2016
Increased use of nitrogen as a fertilizer is often associated with decreased groundwater and surface water quality,and can contribute to negative impacts such as eutrophication or hypoxia, the summary said.
“We estimate the additional nitrogen application due to changes in crop rotations associated with the RFS led to additional nitrous oxide emissions of 3.1 million metric tons in carbon dioxide equivalents, compared to a non-RFS scenario,” the study said. “This represents roughly a 2 to 6 percent increase over existing N2O emissions from all cropland.”