As fertilizer flows from the Midwest, a vast algae bloom thrives below the Mississippi
Every year since the early 1980s, a monstrous algae bloom has risen up in the Gulf of Mexico, fed by fertilizer runoff from Midwest farms. The nasty growth sucks oxygen from the ocean beneath it — snuffing out sea life even as climate change and other human-induced factors threaten the globe’s fish stocks.
Ironically, as fish go belly up in the Gulf, the bulk of the corn and soy grown on Midwest farms ends up in feedlots to fatten the livestock that feed America’s ravenous appetite for meat. The writer Richard Manning described the irony memorably in the Winter 2004 American Scholar (unavailable online):
Already, the Dead Zone has seriously damaged what was once a productive fishery, meaning that a high-quality source of low-cost protein is being sacrificed so that a source of low-quality, high-input subsidized protein can blanket the Upper Midwest.
Well, the quixotic attempt to feed not only our CAFOs but also our cars with Midwestern corn isn’t improving things down in the Gulf. From the St. Louis Post Dispatch (via Denver Post):
[A Louisiana State University] research team reported this week that an area of oxygen-deprived water in the Gulf of Mexico is expected to grow to over 10,000 square miles this year. The largest the area has ever been measured was in 2002, when it was about 8,500 square miles.
Oh dear. And the cause?
“In the past several years, there’s been an expansion of corn, which has the highest fertilizer per acre … and that’s for biofuels,” said R. Eugene Turner, a Louisiana State University professor who directed the study into the gulf’s water quality.
In the course of a normal growing season, huge amounts of fertilizer leach from the Midwest’s corn fields because farmers apply titanic amounts of it to ensure maximum yield. And that factor, as the LSU scientist states, has expanded with the expansion of corn for ethanol.
But I’m not sure if the LSU research team is even taking into account an awful new development in the Midwest: The torrential rains that are pounding the area washing much more fertilizer than normal into the groundwater, down the Mississippi, and into the Gulf.
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