Days after Congress voted to ramp up the government mandate for corn ethanol, bringing it to fully three times current production levels within a decade, we get bracing news from the Gulf of Mexico.

Here is the AP:

The nation’s corn crop is fertilized with millions of pounds of nitrogen-based fertilizer. And when that nitrogen runs off fields in Corn Belt states, it makes its way to the Mississippi River and eventually pours into the Gulf, where it contributes to a growing "dead zone" — a 7,900-square-mile patch so depleted of oxygen that fish, crabs and shrimp suffocate.

This year, the dead zone has reached its third-largest size ever. And with the ethanol boom inspiring farmers to plant ever more corn, activists are bracing for more bad news.

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"We might be coming close to a tipping point … The ecosystem might change or collapse as opposed to being just impacted," an official for the Gulf Restoration Network told AP.

Although farmers in the Midwest can feel the pain of their fishermen peers in the Gulf, their empathy can only go so far. As one Iowa farmer told AP, "I think you have to try to be a good steward of the land … But on the other hand, you can’t ignore the price of corn."

In other words, the market isn’t paying him to take care of the streams that carry nitrogen runoff from his property. Rather, it’s telling him to grow as much corn as possible.

The dead zone may be an unintended consequence of the government-generated ethanol boom; but it’s surely no surprise. It’s been happening every year since 1985, and its size is trending upward.

We’re sacrificing a robust habitat, source of protein, and traditional livelihood in the Gulf to create a fuel of dubious value.

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