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The Best Science Writing Online 2012
Showcasing more than fifty of the most provocative, original, and significant online essays from 2011, The Best Science Writing Online 2012 will change the way...
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HERMANN, Mo. – The Missouri River stretches more than a quarter-mile from shore to shore here, its muddy water the color of coffee with a shot of cream.
The river carved this valley hundreds of thousands of years ago, and in the 1830s, it deposited the German settlers who founded this city. Today, visitors who sip local wine in hillside gazebos can gaze down at the water and imagine being on the Rhine.
For two centuries, Hermann has been known for the Missouri River – and now the river is making Hermann known for an unexpected reason: It is a hot spot for nitrate.
Washing off farms and yards, nitrate is largely responsible for the Gulf of Mexico’s infamous “dead zone.” Nitrate and other nutrients from the vast Mississippi River basin funnel into the Gulf, sucking oxygen out of the water and killing almost everything in their path.
The pollution is one of America’s most widespread, costly and challenging environmental problems, according to the U.S. Environmental Protection Agency. Sewage treatment plants along the rivers already have spent billions of dollars, and some farmers now use computers to apply fertilizer with pinpoint precision.
But after three decades of extensive efforts to clean it up, nitrate along the rivers is getting worse. In Hermann, the levels in the Missouri River have increased 75 percent since 1980, according to U.S. Geological Survey research published last year.
The pollutant continues to pour into the rivers, and ultimately the Gulf, at a growing pace. And no one – at least yet – has figured out exactly why.
1,247 miles downstream
Hermann is an ideal place to start unraveling the mystery. There are no big factories here, no major sewage treatment plants, and not even much of the intensive row-crop agriculture sometimes blamed for heavy runoff. Rather, this small city looks like something out of a German fairy tale. Churches, shops and red-brick houses line tidy streets. Vineyards dot the rolling hills. Tourists arrive via Amtrak train to hear oom-pah bands at Oktoberfest and dine on bratwurst with sauerkraut.
How could Hermann be responsible for increasing the pollution that creates a dead zone 1,247 miles downstream?
The answer is Hermann is merely a microcosm of an immense problem involving 31 states and more than 76 million people.
Hermann sits roughly in the center of the vast Mississippi River basin, which drains 1.24 million square miles stretching from the Rockies to the Appalachians.
The Missouri River, as it rushes past Hermann’s churches and shops, carries the residue of life upstream. Rain washes excess nitrogen and phosphorus, along with other pollutants, from farmers’ fields, cities, factories, cars and suburban lawns into ditches, streams and tributaries, and finally to the river itself. The “Big Muddy” joins the mighty Mississippi just north of St. Louis, then makes a sharp right turn and rushes past the soaring St. Louis Arch on its way to the sea off Louisiana.
When the nutrient-rich water empties into the Gulf far downstream, it triggers a biological phenomenon with deadly results. The nutrients serve as an all-you-can-eat buffet for hungry algae. The phytoplankton population booms and then dies, sinking to the bottom, where bacteria decompose the organisms and use up precious oxygen in the process. The resulting low-oxygen environment – also called hypoxia – is so toxic that all animals must flee or die.
Hypoxia drives away shrimp, crabs and fish and kills creatures such as worms at the bottom of food chains.
“There is die-off, a loss of ecosystem diversity,” said Nancy Rabalais, a marine ecologist and director of the Louisiana Universities Marine Consortium in Chauvin, La. “If you have continuous year-after-year hypoxia, some animals won’t be able to recruit back into the area.”
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8 Comments
Add CommentWhat is needed to get a clearer picture of the problem and its sources is to be able to deploy a large number of remote sensing devices that can monitor the water at many locations without having to send samples to a lab. This would give a better indication as to the principle entry points of the nitrates into the rivers and allow a more responsive methodology for characterizing and controlling the situation.
Reply | Report Abuse | Link to thisAs more data is collected, additional sensors can be deployed to narrow the search for the sources. Once sources are identified, they can controlled using either a nitrate tax to make it too expensive to continue allowing nitrates to enter the system or some other sort of incentive to fix the problem locally.
I am sure that there is room for research in ways to break the nitrates down before they reach the gulf as well. Perhaps systems located at the various dams along the way to process the water as it goes through. It would have to be pretty massive to be able to treat the volumes of water flowing through but perhaps it could be distributed more easily along the streams flowing into the rivers instead.
We do live in a world where everything is interconnected and where the miracle cure for one can be the eternal curse for another. We need to remember that we all need to share this planet and live more harmoniously with it.
I can't believe our rivers and the Gulf are being polluted by those evil, rotten, money-mongering oil companies...oh...wait...I mean, farmers.
Reply | Report Abuse | Link to thisThe world is becoming scarier than ever.
Reply | Report Abuse | Link to thisLittle progress is being made because global resources are being diverted combating a non-pollutant (CO2). The real significant pollutants are losing out of the trillions invested globally, with no resultant effect.
Reply | Report Abuse | Link to thisWe need to re-focus our attention (and money) to real solvable pollution problems. GK
"Little progress is being made because global resources are being diverted combating a non-pollutant (CO2)."
Reply | Report Abuse | Link to thisDenial is a mental disease far more debilitating then liberalism. In the end it results in a terminal disease.
Nitrogen increases cause phytoplankton to multiply, but this should increase nutrients for species in the food chain that consume the plankton. As the dead zone grows, so should the abundance of sea food as the oxygen further out returns to the balance nature established. This is not the case as evidenced by increasingly smaller catches in the gulf. Unfortunately there is other pollutants at work that are destroying the food chain farther out. Pesticides (which are made from petrochemicals) and crude oil which has been purposely sunk to the floor of the gulf (does anyone remember or care who NALCO was or how much they spent on lobbying during the worlds worst oil spill?)is suddenly and suspiciously not investigated or even suspect according to this article. The excuse is just that scientists don't understand it all. Apparently no one is getting paid enough to put the blame where it belongs. It is far more convenient to blame individuals that fertilize their lawns and farmers growing corn for ethanol.
Everything has a cause and effect and it should be a no-brainer to look at the total picture, but Americans have been so dumbed down by the mainstream media which is funded by big business (not liberal environmentalists as claimed by those responsible) that the obvious now becomes the ridiculous as evidenced by G. Karst's post above.
CO2 is as much a part of the problem as the rest of the oil and coal industry's pollutants. CO2 increases the acidity of the water and raises the water temperature which both benefit algae and ultimately plankton production and destroys coral which lives on live plankton, not dead decaying plankton and the poisonous bacteria it creates.
It is hardly a misunderstood problem. It is just another case of active denial by the very people and industries that are creating the problem in the first place.
What humans need to do is weigh the beneficial and non-beneficial attributes and choose solutions based on logic not greed.
Nitrogen fertilizer is depleting oxygen the dead zone of the Gulf. Why not pump air to the bottom of the gulf like is done in fish tanks? Why not pay for the operation by a tax on nitrogen fertilizer? Let the polluters pay for the consequences of their pollution.
Reply | Report Abuse | Link to thisIn my opinion, the hidden factor here is depletion of the soil in terms of buried carbon. i.e the nitrogen is not being retained as well by the soil because it is becoming more and more just a 'dry hydroponics' sterile medium.
Reply | Report Abuse | Link to thisWe need to make better soil by getting away from the idea that agriculture is about adding nutrients to a dead inorganic media designed only to stabilize the root system.
Move towards ways of allowing more nutrients from fertilizer to be retained, such as biochar, burying stalks, low tillage, etc. Maybe even letting fields lie fallow and alternating to give bacterial and worms time to establish themselves between crops. Investigate multiple crops in the same field (I know it makes harvesting more complicated but nutrients may be taken up faster. We need to develop actual soil as it is MUCH more resistant to losing nutrients than the basic minerals.
Looking over the responses, I despair of the public seeing agriculture as a biological process. They seem to regard it as an industrial one.
Of course doing the common sense thing and completely eliminating the levees south of New Orleans is just not considered of course.
Reply | Report Abuse | Link to thisIf this was done the waters of the Mississippi would then be filtered by the remaining marshlands that CAN utilize those excess nutrients and regrow themselves.
Destruction of these levees doesn't have to entail destroying communities if done right, but like I said since it's not even considered as an option proper planning has never been done. How pathetic.