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Hungry Crustaceans Eat Climate Change Experiment
Earlier this month, an expedition fertilized 300 square kilometers of the Atlantic Ocean with six metric tons of dissolved iron. This triggered a bloom of phytoplankton, which doubled their biomass within two weeks by taking in carbon dioxide from the seawater. The dead phytoplankton were then expected to sink to the ocean bed, dragging carbon along with them. Instead, the experiment turned into an example of how the food chain works, as the bloom was eaten by a swarm of hungry copepods. The huge swarm of copepods were in turn eaten by larger crustaceans called amphipods, which are often eaten by squid and whales. "I think we are seeing the last gasps of ocean iron fertilization as a carbon storage strategy," says Ken Caldeira of the Carnegie Institution at Stanford University. While the experiment failed to show ocean fertilization as a viable carbon storage strategy, it has pushed the old "My dog ate my homework" excuse to an unprecedented level.
Algae --> Copepod --> Amphipod --> Whale blubber/exhaled CO2
Note that the whale blubber is eventually converted into CO2 as well.
Even if the whale dies and sinks to the ocean floor, only a small portion of the 'sequestered' carbon would not make it back into the atmosphere eventually (plenty of deep-sea animals consume whale carcasses, all the while converting the 'sequestered' carbon into CO2.
Maybe a tiny bit would be converted to Ca2CO3 by molluscs, but AFAIK, no shell-forming molluscs feed on deep-sea whale carcasses.
"Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
From TFA: The tiny crustaceans graze on phytoplankton, which keeps the carbon in the food chain and prevents it from being stored in the ocean sink. The goal was to get the carbon out of the food chain and dormant on the ocean floor.
The problem is that a lot of tree planting exercises involve slim, fast-growing trees that absorb little CO2 but do absorb excessive soil nutrients. These trees have a short life-expectancy and usually end up getting dumped in land-fills where they replenish the CO2 in the air.
You have to use much slower-growing trees. The bulkier the better, the longer-living the better. I've found Californian Redwoods grow great even in the north of England (which is no great surprise, as prior to the Ice Age that was part of their territory) and it was fine to take them into the country when I last checked (no parasites and no known conflicts with native species - or, since it's a re-introduction, other native species).
Also in England, I would strongly advise planting English Oaks. They're getting rare as it is, but they are also one of the more long-lived of the oak family and again should be excellent carbon sinks.
In the US, as bristlecone pines operate best in areas most other species cannot survive in, I would imagine that it would be possible to increase their range without causing too much of an environmental problem.
Wollemi Pines might also be a good bet, as there is no risk of them getting out of control (they can't compete with flowering trees or plants) and again there should be an extremely low risk of problematic parasites.
If you like getting real christmas trees, get one with roots. Even if only one in a hundred make it through christmas intact, that would still be a massive cut in the CO2 injected back into the atmosphere. (Some places dump trees in lakes, but that acidifies the lakes and probably causes all kinds of other environmental problems.)
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
The carbon absorbed by the phytoplankton is used as energy source by successively larger animals in the food chain. To extract energy from it they burn it, releasing the resulting CO2 to the water. From there it eventually gets back in the atmosphere.
In other words, the whole process is CO2-neutral instead of being a CO2-sink as was hoped for.
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Good question!! Here's why:
The hypothesis supposed that the plankton would fall to the bottom of the ocean and ultimately turn into oil. Instead the biomass is being turned into energy by large predators, to do this they release CO2 that was stored in the biomass back into the environment.
Biomass is a great way to TEMPORARILY sequester CO2, but unless you can remove the biomass from the rest of the biosphere (where it will be used) the CO2 will be released as the biomass is converted into energy.
The experiment thought they could move the biomass low enough in the water column that it would no longer be used by other creatures.