Gulf of Mexico Dead Zone Smaller Than Expected

Good news doesn’t come as often as we’d like nowadays, so it’s nice to be able to report that this year’s Gulf of Mexico dead zone isn’t nearly as large as experts thought it would be. NOAA-sponsored forecast models predicted that it would be bigger than usual at 7,000 – 8,000 square miles, but the actual size is about 3,000 square miles.

However, the change in square miles doesn’t mean it’s any less severe than usual. In fact, it’s worse. This year’s dead zone is “unusually thick”, reaching from the ocean floor almost to the surface of the water. And the smaller size doesn’t mean that the amount of pesticide-laden runoff that causes the dead zone in the first place has decreased.

From PhysOrg, via Treehugger:

“The results of the 2009 cruise at first glance are hopeful, but the smaller than expected area of hypoxia appears to be related to short-term weather patterns before measurements were taken, not a reduction in the underlying cause, excessive nutrient runoff.” said Robert Magnien, PhD., director of NOAA’s Center for Sponsored Coastal Ocean Research. “The smaller area measured by this one cruise, therefore, does not represent a trend and in no way diminishes the need for a harder look at efforts to reduce nutrient runoff.”

The average size of the dead zone over the past five years, including this cruise, is now 6,000 square miles. The interagency Gulf of Mexico/Mississippi River Watershed Nutrient Task Force has a goal to reduce or make significant progress toward reducing this dead zone average to 2,000 square miles or less by 2015. The Task Force uses a five year average due to relatively high interannual variability.

The solution is reducing fertilizer use on farms along the Mississippi River. When too much fertilizer is applied, the excess runs off into the river and is carried all the way to the Gulf, depriving the waters of oxygen and making them unlivable for most marine life. Treehugger reports that one proposed solution is crop biodiversity, which would cut down on the need for chemicals on farms.

Link [Phys Org] via [Treehugger]
Photo credit: NOAA

Peak Oil, Peak Water… Peak Dirt?

Right now, there are proclamations of peak everything: peak oil, peak water, peak rice, peak metal, even peak guano. But would you ever have thought it possible to run out of dirt? It seems limitless, but in truth dirt is far more complicated than most people realize, and there were bound to be some consequences to the farming methods and chemicals that have been used in recent history.

From Planet Green:

Really, Peak Dirt- the world is losing soil 10 to 20 times faster than it is replenishing it. Drake Bennett in the Boston Globe tells us that dirt is complicated stuff, made from sand or silt, then years of plants adding nutrition, bugs and worms adding their excrement, dying and rotting.

“The resulting organic matter feeds a whole underground ecology that aerates the soil, fixes nutrients, and makes it more hospitable for plant life, and over time the process feeds back on itself. If the soil does not wash away or get parched by drought, it very gradually thickens. It takes tens of thousands of years to make 15 centimeters of topsoil, about 6 inches’ worth.”

Till it and plant a monoculture like corn on it and that soil gets depleted rapidly, so farmers add fertilizer, lots of it. The philosophy was “Well, if your soil’s degraded, just put some more fertilizer on, or till it another time and you can get the same crop yield,” says David Laird, a soil scientist.

So, what’s causing it? Lloyd Alter explains on Planet Green that ethanol, peak oil and meat are to blame. ‘Excessive demand for grain’, caused mainly by ethanol and meat production, has caused a huge increase in the use of fertilizer. Luckily, scientists are working on replenishing the soil with traditional farming methods, biochar and making soil from scratch. Check out the Planet Green article for the details.

Link [Planet Green]
Photo credit: Flickr user Crystl

Peru Turning to Armed Guards to Protect Precious Bird Shit

You may have heard of Peak Oil, but how about Peak Guano? Guano, otherwise known as bird shit, was once so much in demand that wars were fought over it. After synthetic fertilizer was invented, the industry nearly went extinct – but as organic fertilizers come back into vogue, officials in Peru are finding themselves needing to protect it again.

From The New York Times:

The worldwide boom in commodities has come to this: Even guano, the bird dung that was the focus of an imperialist scramble on the high seas in the 19th century, is in strong demand once again.

“Before there was oil, there was guano, so of course we fought wars over it,” said Pablo Arriola, director of Proabonos, the state company that controls guano production, referring to conflicts like the Chincha Islands War, in which Peru prevented Spain from reasserting control over the guano islands. “Guano is a highly desirous enterprise.”

It is a minor miracle that any guano at all is available here today, reflecting a century-old effort hailed by biologists as a rare example of sustainable exploitation of a resource once so coveted that the United States authorized its citizens to take possession of islands or keys where guano was found.

Guano sells for $250 per ton, going up to $500 when it’s headed to countries like the U.S., France and Israel. While it’s highly prized as an organic fertilizer, it isn’t all rosy. The anchovies that the seabirds eat to produce the rich guano are being overfished, and the bird population is shrinking. Peru is working hard to protect the birds, going so far as to introduce lizards to hunt down ticks that infest the birds and posting armed guards to prevent fisherman from scaring them away. Where once 60 million seabirds flew overhead, there are now only about 4 million.

Peak Guano is coming, no doubt about it:

Uriel de la Torre, a biologist who specializes in conserving the guanay cormorant and other seabirds, said that unless some measure emerged to prevent overfishing, both the anchovetas and the seabirds here could die off by 2030.

“It would be an inglorious conclusion to something that has survived wars and man’s other follies,” Mr. de la Torre said. “But that is the scenario we are facing: the end of guano.”

Link [The New York Times] via [Treehugger]
Photo credit: Tomas Munita for The New York Times