Iron-fertilizing experiment took place in worst possible spot, say scientists
Impossible to determine how iron affected the study without proper isolation
By Zoe McKnight, Vancouver Sun October 24, 2012
Of all the vast area covered by the Pacific Ocean, the coastal waters off Haida Gwaii are one of the worst spots to conduct an iron fertilization experiment, scientists say.
And yet over the summer, 100 tonnes of iron sulphate and 20 tonnes of iron oxide were scattered 370 kilometres off the coast of Haida Gwaii, right in the path of the Haida eddies, during the first and only project undertaken by the Haida Salmon Restoration Corp. The $2.5-million exercise was a purported attempt to measure how the iron - which is water-soluble - added to the ocean could enhance declining salmon stocks.
The Haida eddies, clockwise-rotating areas of water up to 300 kilometres in diameter, are known to carry iron-rich coastal water out to sea, where there is less iron and therefore less ocean life. The eddies form off the southern tip of the island and become highly concentrated with phytoplankton and chlorophyll, which is readily visible as a "bloom" from satellites as they travel through the northeast Pacific.
The iron fertilization project garnered worldwide attention and criticism from the scientific community.
Scientists from around the world have studied the ocean currents near the archipelago, and many expressed concern over the environmental effects on what is considered pristine water.
But experts also say adding iron to this particular ocean region would obscure any data collected by the salmon restoration company because it would be impossible to tell if any growth in fish food - plankton - was a result of added iron or the eddies.
"If you were going to plan to do an experiment to demonstrate the impact of iron fertilization, you wouldn't dump it into a Haida eddy, I don't think," said Jay Cullen, an ocean scientist who runs a lab at the University of Victoria that studies chemicals and trace metals in marine environments.
"If a group were to fertilize such a feature with iron, it would be next to impossible to determine how productivity and phytoplankton biomass was influenced by the treatment," he said, calling it "bad scientific design."
A well-designed experiment would include a way to distinguish between water with iron added and water without, to isolate the impact of adding the iron by using a control water sample.
Outside the eddies, iron concentration offshore is low because its source is land and the northeast Pacific is ane-mic compared to coastal water. John Disney, the company's CEO and economic development officer of Old Massett, has displayed satellite images of new plankton growth. But from space, the Haida eddies were already visible because of the algae blooms - Canadian studies show a naturally occurring spring bloom and another in late fall.
The company has also stated that analysis of the iron-treated water samples is ongoing, but no results have been released.
New Zealand ocean scientist Cliff Law, who has been involved in open-ocean iron addition experiments in the Gulf of Alaska, also cast doubt on the project's scientific process.
He said a portion of the iron would have been lost to sinking, and that 100 tonnes is a far greater amount than has been attempted in controlled experiments.
"The images I've seen from the recent experiment show an eddy of high chlorophyll, but you'll see in the same image other eddies and also water along the shelf contains high levels of chlorophyll, so there's an issue of verification here, how do they know that the phytoplankton bloom in the satellite images is the result of the iron they added and not just natural," he wrote in an email.
While the Old Massett Village Council has defended its methods, the Council of the Haida Nation has distanced itself from the project, and Environment Canada is conducting an investigation.
That agency's enforcement officers met with company officials in May, when they were informed that an iron ore deposit in the water would violate the Canadian Environmental Protection Act, unless it was for "legitimate research."
The federal Environment Minister Peter Kent was not made aware of the iron deposit until it had happened, his press secretary James Sweet said Tuesday, adding an investigation began Aug. 30.
The iron deposit also likely contravenes the United Nation's London Convention, which prohibits ocean dumping for reasons other than research, because the iron was scattered in international water just past the Canadian jurisdictional boundary.
Several researchers at the Department of Fisheries and Oceans are considered experts on the Haida eddies, and an entire issue of the journal Deep Sea Research II has been devoted to the phenomena.
That ministry refused a request for comment, citing the Environment Canada investigation.
HOW HAIDA EDDIES PRODUCE ALGAE BLOOMS
Ocean currents push iron-rich waters into the open ocean, encouraging growth
1. Haida eddies
are created by ocean currents and are formed at the base of Haida Gwaii. They rotate clockwise into the east Pacific, heading to the Alaskan Gyre, and can measure 150 to 300 km in diameter.
2. Algae or plankton is the base of the
food chain and requires iron for metabolic purposes. Most iron found in oceans originates on land, while offshore waters contain less iron. When the iron-rich Haida eddies come into contact with the iron-deficient offshore water, it encourages the growth of phytoplankton. The resulting algae "blooms" are visible from satellite. Blooms typically occur in the spring and in late summer or early fall.
3. Phytoplankton, through photosynthesis, absorb carbon dioxide - just like plants - and release oxygen as a waste product. Phytoplankton sink after they die and decompose at a level that's no longer in contact with the atmosphere. While it's been suggested plankton blooms act as a carbon sink, research suggests the process is unreliable.
zmcknight@vancouversun.com
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