It is easy to overlook the small when investigating the carbon budgetof the biome. The actual mass easily far exceeds what is obvious. Thus we see a continuous down flux of rich carbon based food to theocean bottom although surely a lot of that is just as efficientlyreabsorbed and reprocessed. Some of it may well even make it back upas methane rather quickly.
What is important is that the sea bottom sea surface cycle will turnout to be remarkably robust and modestly interacting with theatmosphere. Sunlight and CO2 is feeding it just as it feeds the landsurface. It should be obvious that additional nitrification willaccelerate draw down of CO2 frfom the atmosphere.
In the long term we need to think about that a little more. My bestoption is to suspend a neutral pipe into the nutrient rich deep andallow natural pressure to hurl water into the surface at well pickedlocations. This also could be used to suppress hurricane developmentas the surface would be also chilled a little. I would particularlytake advantage of the Midatlantic Ridge if that is possible and anyother sea mounts that provide convenient anchoring points
Small fish can playa big role in the coastal carbon cycle
by David Malmquist
Gloucester PointVA (SPX) Oct 11, 2012
http://www.terradaily.com/reports/Small_fish_can_play_a_big_role_in_the_coastal_carbon_cycle_999.htmlA study in this week'sissue of Scientific Reports, a new online journal from the NaturePublishing Group, shows that small forage fish like anchovies canplay an important role in the "biological pump," theprocess by which marine life transports carbon dioxide from theatmosphere and surface ocean into the deep sea-where it contributesnothing to current global warming.
The study, by Dr. Grace Saba of Rutgers University and professorDeborah Steinberg of the Virginia Institute ofMarine Science,reports on data collected on an oceanographic expedition to theCalifornia coast during Saba's graduate studies at VIMS. Saba, now apost-doctoral researcher in Rutgers' Institute of Marine and CoastalSciences, earned her Ph.D. from the College of William and Mary'sSchool of Marine Science at VIMS in 2009.
The expedition, aboardthe research vessel Point Sur, was funded by the National ScienceFoundation.The study's focus onfish is a departure for Steinberg and colleagues in her ZooplanktonEcology Lab, who typically study tiny crustaceans called copepods.
Researchby Steinberg's team during the last two decades has revealed thatcopepods and other small, drifting marine animals playa key role in the biological pump by grazing on photosynthetic algaenear the sea surface, then releasing the carbon they've ingested as"fecal pellets" that can rapidly sink to the deep ocean.The algal cells are themselves generally too small and light to sink.
"'Fecal pellet'is the scientific term for "poop," laughs Steinberg."Previous studies in our lab and by other researchers show thatzooplankton fecal pellets can sink at rates of hundreds to thousandsof feet per day, providing an efficient means of moving carbon todepth. But there have been few studies of fecal pellets from fish,thus the impetus for our project."
Saba says, "Wecollected fecal pellets produced by northern anchovies, a foragefish, in the Santa Barbara Channel off the coast of southernCalifornia." She determined that sinking rates for theanchovies' fecal pellets average around 2,500 feet per day,extrapolating from the time required for pellets to descend through acylinder of water during experiments in the shipboard lab.
At that rate, saysSaba, "pellets produced at the surface would travel the 1,600feet to the seafloor at our study site in less than a day."
Saba and Steinbergalso counted the pellets' abundance-up to 6 per cubic meter ofseawater, measured their carbon content-an average of 22 microgramsper pellet, and painstakingly identified their partly digestedcontents-mostly single-celled algae like dinoflagellates and diatoms.
"Twentymicrograms of carbon might not seem like much," says Steinberg,"but when you multiply that by the high numbers of forage fishand fecal pellets that can occur within nutrient-rich coastal zones,the numbers can really add up."
Saba and Steinbergcalculate that the total "downward flux" of carbon withinfish fecal pellets at their study site reached a maximum of 251milligrams per square meter per day-equal to or greater thanpreviously measured values of sinking organic matter collected bysuspended "sediment traps."
"Our findingsshow that-given the right conditions-fish fecal pellets can transportsignificant amounts of repackaged surface material to depth, and doso relatively quickly," says Saba.
Those conditions arelikely to occur in places like the western coasts of North and SouthAmerica, where ocean currents impinge on continental shelves,bringing cold, nutrient-rich waters from depth into the sunlitsurface zone.
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