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Meditating
Raw Newbie
HUFFINGTON POST – July 23, 2008
HOUSTON — A “dead zone” in the Gulf of Mexico off the Texas-Louisiana coast this year is likely to be the biggest ever and last longer than ever before, with marine life affected for hundreds of miles, a scientist warned.
“It’s definitely the worst we’ve seen in the last five years,” said Steve DiMarco, a Texas A&M University professor of oceanography who for 16 years has studied the Gulf of Mexico dead zone, so named because the oxygen-depleted water can kill marine life.
The phenomenon is caused when salt water loses large amounts of oxygen, a condition known as hypoxia that is typically associated with an area off the Louisiana coast at the mouth of the Mississippi River. The fresh water and salt water don’t mix well, keeping oxygen from filtering through to the sea bottom, which causes problems for fish, shrimp, crabs and clams.
This year’s dead zone has been aggravated by flood runoff from heavy spring rains and additional runoff moving into the Gulf from record floods along the Mississippi.
DiMarco, joined by researchers from Texas A&M and the University of Georgia, just returned from an examination of 74 sites between Terrebonne and Cameron, La. He said the most severe hypoxia levels were recorded in the mid-range depths, between 20 and 30 feet, as well as near the bottom of the sea floor at about 60 feet.
Some of the worst hypoxic levels occurred in the western Gulf toward the state line.
“We saw quite a few areas that had little or no oxygen at all at that site,” DiMarco said Tuesday. “This dead zone area is the strongest we’ve seen since 2004, and it’s very likely the worst may be still to come.
“Since most of the water from the Midwest is still making its way down to the Gulf, we believe that wide area of hypoxia will persist through August and likely until September, when it normally ends.”
Last year, DiMarco discovered a similar dead zone off the Texas coast where the rain-swollen Brazos River emptied into the Gulf.
The zone off Louisiana reached a record 7,900 square miles in 2002. A recent estimate from the National Oceanic and Atmospheric Administration and Louisiana State University shows the zone, which has been monitored for about 25 years, could exceed 8,800 square miles this year, an area roughly the size of New Jersey.
DiMarco said a tropical storm or hurricane likely would have no impact on this year’s zone, believed to be caused by nutrient pollution from fertilizers that empty into rivers and eventually reach the Gulf.
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FYI to those interested:
August 14, 2008
WASHINGTON (AP)—Like a chronic disease spreading through the body, “dead zones” with too little oxygen for life are expanding in the world’s oceans. A graduate student researches ocean “dead zones” with a monitoring device off the coast of Oregon.
A graduate student researches ocean “dead zones” with a monitoring device off the coast of Oregon.
“We have to realize that hypoxia is not a local problem,” said Robert J. Diaz of the Virginia Institute of Marine Science. “It is a global problem, and it has severe consequences for ecosystems.”
“It’s getting to be a problem of such a magnitude that it is starting to affect the resources that we pull out of the sea to feed ourselves,” he added.
Diaz and co-author Rutger Rosenberg report in Friday’s edition of the journal Science that there are now more than 400 dead zones around the world, double what the United Nations reported just two years ago.
“If we screw up the energy flow within our systems, we could end up with no crabs, no shrimp, no fish. That is where these dead zones are heading unless we stop their growth,” Diaz said.
He said the newest dead areas are being found in the Southern Hemisphere: South America, Africa, parts of Asia.
Some of the increase is because of the discovery of low-oxygen areas that may have existed for years and are just being found, he said, but others are actually new. Don’t Miss
Pollution-fed algae, which deprive other living marine life of oxygen, are the cause of most of the world’s dead zones. Scientists mainly blame fertilizer and other farm runoff, sewage and fossil-fuel burning.
Diaz and Rosenberg, of the University of Gothenburg in Sweden, conclude that it would be unrealistic to try to go back to pre-industrial levels of runoff.
“Farmers aren’t doing this on purpose,” Diaz said. “The farmers would certainly prefer to have their [fertilizer] on the land rather than floating down the river.”
He said he hopes that as fertilizers become more and more expensive, farmers will begin seriously looking at ways to retain them on the land.
New low-oxygen areas have been reported in Samish Bay of Puget Sound, Yaquina Bay in Oregon, prawn culture ponds in Taiwan, the San Martin River in northern Spain and some fjords in Norway, Diaz said.
A portion of Big Glory Bay in New Zealand became hypoxic after salmon farming cages were set up but began recovering when the cages were moved, he said.
A dead zone has been newly reported off the mouth of the Yangtze River in China, Diaz said, but the area has probably been hypoxic since the 1950s. “We just didn’t know about it,” he said.
Some of the reports are being published for the first time in journals accessible to Western scientists, he said.
Nancy N. Rabalais, executive director of the Louisiana Universities Marine Consortium, said she was not surprised at the increase in dead zones.
“There have been many more reported, but there truly are many more. What has happened in the industrialized nations with agribusiness as well that led to increased flux of nutrients from the land to the estuaries and the seas is now happening in developing countries,” said Rabalais, who was not part of Diaz’s research team.
She said she was told during a 1989 visit to South America that rivers there were too large to have the same problems as the Mississippi River. “Now, many of their estuaries and coastal seas are suffering the same malady.”
“The increase is a troubling sign for estuarine and coastal waters, which are among some of the most productive waters on the globe,” she said
Meditating that is highly disturbing news…
Huffington Post is a very credible source too (IMHO)...
AUGUST 18, 2008
GULF OF MEXICO (CNN)—Fisherman Terry Pizani turns his captain’s wheel with a mournful expression on his face. Far below, the fishing grounds off the Louisiana coast where the 63-year-old has made a living for five decades have become an aquatic graveyard known as a “dead zone.”
Fisherman Terry Pizani’s shrimp catch is not as plentiful because of the Gulf of Mexico’s “dead zone.” “You don’t see nothing,” he said. “Usually you see bait fish on the water. You don’t see no bait fish, nothing. Nothing’s there.
“I don’t have no kind of testing material to test the water, but I know something’s wrong.”
Oceanographers who test the Gulf of Mexico waters every month confirm the veteran fisherman is right.
“We’re not finding enough oxygen to support life, aquatic life,” said scientist Lora Pride aboard the Pelican, the Louisiana Universities Marine Consortium research vessel that studies the Gulf.
CNN traveled aboard the ship August 14-15 as consortium researchers sent sensors to the bottom of the sea, scooped up sediment and collected water samples for analysis at nine testing stations in the Gulf.
As an oxygen meter sank far below the Pelican, Pride pointed to an onboard computer screen displaying the meter’s findings in real time.
“This green line is the oxygen right here and at the bottom it’s reading less than 2 milligrams per liter,” Pride said.
Six of the nine stations revealed such oxygen-deprived, hypoxic water, compared to a normal reading of 6 milligrams per liter.
As Pride and her crew aboard the Pelican monitored the Gulf waters, the journal Science last week published a study that reveals there are more than 400 dead zones around the globe, double the number found by the United Nations two years ago.
One of the major dead zones is in the Gulf of Mexico. It is 8,000 square miles, nearly the size of New Jersey, according to the marine consortium’s annual measurement completed in July.
“There’s no oxygen in the water for shrimp, crabs, fish to live,” said Nancy Rabalais, executive director of the consortium.
Fish and shrimp “can sense that and they start to move out of the area. Otherwise they would die. The animals that still remain in the sediments have to keep breathing. There is not enough oxygen and eventually they will die off,” Rabalais said.
Scientists have been studying the Gulf’s dead zone for about 20 years, although its existence has been known for decades. So why is oxygen disappearing from fishing waters in the Gulf of Mexico? The answer, scientists say, is found hundreds of miles to the north, up the Mississippi River in corn country.
Farmers in Iowa and across the Midwest use tons of nitrogen and phosphorous to make their cornfields more productive, which allows the farmers to take advantage of high corn prices resulting from growing demand from ethanol factories and developing countries.
Rain always causes some fertilizer to run off farmland, but this summer’s historic flooding caused even more runoff into rivers that flow into the Mississippi.
“That’s the primary source of the nutrients that go to the Gulf of Mexico,” said Rabalais. “And so the size of the low-oxygen zone has increased in proportion to these nutrients reaching the Gulf.”
Fertilizer flowing into the Gulf of Mexico triggers an overgrowth of microscopic algae, which eventually die and fall to the bottom.
“When they die, they decompose, and decomposition requires oxygen,” said Pride. “So these things will fall to the bottom and as they decompose they consume oxygen.”
So much oxygen is taken from the water that slow-moving sea life like clams, small crabs, starfish and snails suffocate.
“We go diving down there quite frequently,” said Melissa Baustain, a doctoral candidate at Louisiana State University. “The deeper we go down in the water, it gets kind of scary because there’s nothing there. There’s no fish, there’s no organisms alive, so it’s just us,” Baustain said.
“It’s dark and it’s turbid because all that algae that is dying, that’s sinking through the water column.”
To find lots of shrimp, fishermen like Pizani have to travel to the edge of the dead zone. He calculated that it costs him $450-a-day in diesel fuel to fish.
“You just gotta keep going miles and miles and miles and hopefully you’ll run into something,” he said. “The fuel costs are so high it’s just not feasible to get out there unless you can catch a boatload, really make any money out of it.”
So, many boats are idle. Others are staying away from their home port in Grand Isle, Louisiana, a disaster for seafood processor Dean Blanchard, who buys shrimp from fishermen.
“All my boats have to go somewhere else to make a living. It’s a shame,” Blanchard said.
“This is the prime shrimping ground in the country right here and it shut us down. It just shut us down. It’s unreal.”
With demand for corn growing, scientists say the dead zone could expand in coming years.
August 14, 2008 – TIME
Over the past two or three decades, scientists have noticed with growing alarm that vast stretches of coastal waters are turning into dead zones, patches of seabed so depleted of oxygen that few creatures, if any, can survive there. In 2004, the United Nations Environment Program (UNEP) took stock of the phenomenon, which is caused in large part by agricultural runoff, and pronounced it one of the biggest environmental problems of the 21st century. Two years later it noted that the number of identified dead zones, some of which cover thousands of square miles, had climbed from 150 to 200.
Predictably, things have gotten worse since then. Robert Diaz, an ecologist at the College of William and Mary in Virginia who helped UNEP with its numbers, reports in the current issue of the journal Science that today there are more than 400 known dead zones along coastlines around the world, covering roughly 95,000 sq. mi. of seabed. Some of the dead zones that Diaz and his Swedish co-author identify in their review have been around for some time, but have only recently been studied. Many others appear to be new. About 8% of them, mainly those in the Baltic and North seas, persist throughout the year, says Diaz; half, including one the size of New Jersey in the Gulf of Mexico, form mainly seasonally, typically beginning in summer after the spring thaw and receding in the fall. Overall, the researchers found that the number of new dead zones has grown exponentially over the past four decades.
That’s bad news for fish and for the people who eat them. Much of the world’s fish supply is already troubled due to overfishing, dying reefs and the disappearance of marshland, mangrove forests and other coastal environments that serve as breeding grounds and nurseries for many valuable species. Biologists haven’t been able to figure out how much oxygen depletion alone contributes to the decline of teetering fisheries. The question is hotly debated in marine-science circles these days but few experts would disagree that an increase in dead zones can only be a detriment.
Indeed, severe hypoxia, as scientists refer to the phenomenon, has been linked to the collapse of fisheries in the Baltic Sea, the Black Sea (which has since recovered) and a lobster fishery in the Kattegat, a patch of the North Sea between Denmark and Sweden. Other headline examples exist as well, but, more often, hypoxic waters have a relatively subtle impact on fish. “Most of the effects of low oxygen on fish stocks are what we call ‘sub-lethal,’ ” says Diaz. “It doesn’t kill the fish but stresses them. It affects their growth, it reduces their reproductive output, and makes them more susceptible to disease.”
Dead zones are created when excess nitrogen and other pollutants in ocean water promote large blooms of algae and phytoplankton on the surface. The nitrogen gets there in a couple of ways: through river water filled with fertilizer from farm runoff and from air polluted with tailpipe and smokestack emissions. When the algae die and sink to the ocean floor, bacteria there break them down, while consuming pretty much all of the available oxygen in the water. The bacteria also proliferate wildly, taking over the ecosystem and exacerbating the oxygen depletion. If conditions like strong currents, which are common in summer, prevent oxygen-rich water from the surface from mixing with lower layers, bottom-dwelling animals like lobsters, crabs and flounder in that area either flee or die. Relatively immobile animals such as oysters, clams and worms are particularly susceptible to annihilation. Such deaths take the bottom out of the marine food chain, helping to create sustained dead zones.
The best way to prevent this from happening would be to reduce the amount of nitrogen introduced into the ocean. The technology already exists to do that. If, for example, farmers in the upper part of the U.S. were given a financial incentive to plant crops like winter wheat, rather than leaving their fields fallow after the fall harvest, says marine ecologist Robert Howarth of Cornell University, much of the nitrogenous fertilizer that would normally get washed into waterways by spring thaws could instead be absorbed into winter grain crops. Measures of this sort, if uniformly implemented, could all but eliminate the Gulf of Mexico’s famously ballooning dead zone.
Such changes to farm management aren’t likely to be cheap or easy to implement. But, as Diaz’s study suggests, the consequences of inaction might prove infinitely more expensive. “The oceans are vast and they cover most of the Earth’s surface,” notes Howarth. “But what people mostly care about in the oceans is largely in these coastal areas. That’s where the most productive fisheries are, and where people recreate. And that’s where people are overfishing, and where dead zones are developing.”
Good stuff, Meditating. Well, tragic, actually.
oh my. Humans are destroying the earth even more quickly than I ever thought possible. I’m going to plan my permaculture now… at least I’ll be one person living sustainably off the land, even while the rest of the world heads in a dangerous direction.
I know farmers that are paid NOT to plant.