Scientists are predicting one of the largest dead zones ever in the Gulf of Mexico this year, with estimates ranging from 7,286 to 8,561 square miles, or as large as the state of New Jersey. Dead zones are the oxygen-deprived bottom waters of bays and oceans. The lack of oxygen kills off bottom-dwelling marine organisms and chases away others that can no longer survive in them.
At least 400 dead zones have been identified in coastal oceans around the world. One of the biggest is in the Gulf of Mexico. The Gulf dead zone is an annual occurrence caused mainly by fertilizer runoff in the Mississippi River watershed. Nitrogen from fertilizers seeps into local waterways and then the Mississippi River, and makes its way south into the Gulf, where it promotes dense algae growth on the sea floor. When the algae die at the end of the season, the decomposition sucks up much of the available oxygen, making the bottom waters uninhabitable to animals. According to researchers, 153,000 metric tons of nutrients, most from chemical fertilizers, flowed in to the Gulf in May alone.
Corn is the most chemical-intensive crop grown in America, accounting for nearly half of nitrogen and phosphorous fertilizer use, as well as 40 percent of herbicides and over 80 percent of the gender-bending weed-killer atrazine. Corn acreage has been rising for a number of years, driven by demand for corn to make ethanol. Today, ethanol claims an astounding 40 percent of the U.S. corn harvest. As a result, over 97 million acres of corn were planted this year, the highest on record since 1936.
With historically high levels of corn cultivation has come a sharp rise in the practice of planting corn every year instead of rotating it (i.e. growing it in alternate years) with other crops like soybeans. Corn-on-corn, as it's known in farming circles, exacerbates the adverse impacts of corn cultivation in a number of ways, including still greater fertilizer use, more fungicide spraying, and more soil-eroding tillage.
One important reason that farmers have traditionally avoided growing corn every year is the greatly increased risk of infestations of corn rootworm, a corn farmer's worst pest. This is where genetically-engineered (GE) corn comes in. Most GE corn carries a rootworm toxin, meaning the corn plant itself is poisonous to the rootworm. Monsanto encourages corn-on-corn farming and has even given clinics to entice farmers to drop their beneficial rotations and adopt this extremely bad practice.
As a result, Rootworm resistance to GE corn toxin is on the rise in several states, and it has arisen primarily in fields planted continuously to Monsanto's GE corn. In an effort to prevent or respond to resistant rootworm, farmers are turning to even more hazardous chemical pesticides.
Misguided U.S. agricultural policy is driving historically high levels of corn cultivation through massive support for ethanol production. GE corn is facilitating this misguided policy by making it possible to grow corn-on-corn, but only at the cost of rootworm resistance and increased use of toxic chemical insecticides and fungicides. Still worse, more corn means more fertilizers washing into the waterways, which in turn generate an ever-widening dead zone in the Gulf of Mexico.
Some concerned and conscientious farmers are beginning to engage in positive mitigation strategies, including crop rotation, cover cropping, and no- or low-till practices that reduce soil erosion and runoff -- practices that organic and agro-ecological farmers have been using for years with much success. Biological diversification can fortify soil integrity and increase nutrient levels to revitalize farmland and bolster crop health. A growing citizens' movement is working to reclaim control of our food and agricultural policy from the likes of Monsanto and Dow. From efforts to secure mandatory labeling of GE foods, end the use of bee-toxic insecticides, and stop concentrated animal feeding operations, citizens do have the ability to make real change.
To learn how you can make a difference and learn about the foods you eat, visit the Center for Food Safety website and download the Shoppers Guide.