Only mother nature knows how to fertilize the ocean
Natural input of nutrients works ten times better than manmade injections.
Blooms of algae created by pumping nutrients into the ocean can suck up at least ten times more carbon dioxide (CO2) from the atmosphere than was previously thought. But the findings lend no support to controversial schemes to encourage such blooms in order to reduce global warming, the authors warn.
Comments
You report Ulf Riebesell : " has been involved in one previous ocean fertilization experiment" Have there been as many as six so far?
If so , his contention that "What the team has observed is probably the optimal efficiency of carbon export achievable, you just can't achieve nature's efficiency... That's why geo-engineering the ocean won't work." deserves to be taken with a fair-sized grain of ferrous sulfate.
One does not expect a new species of engineering , Geo- or otherwise to converge on the limits of nature or thermodynamics on the first half dozen tries.
The notion that iron atoms touched by man are somehow different from those upwelling from the deep green sea has a less than bracing odor of Vitalism about it.
Posted by: Russell Seitz | April 27, 2007 03:41 PM
Two thoughts struck me about the article and the comment by Russell Seitz.
The authors speculate that the upwelling currents bring more than iron from the deep ocean. In fact both modeling and experiments have shown that HNLP (high nutrient, low productivity) regions require more than a single nutrient to reach their full potential. To maximize artificial production researchers will need a more detailed list of which micronutrients the local flora demand. The problem has less to do with vitalism than with an overemphasis on the value of iron alone.
Second, I think that the importance of biotic adaptation is underplayed here. Being mostly naive to the experience of a nutrient surge the phytoplankton community in HNLP regions should and does lack the ability to utilize one to its theoretical limit. The phytoplankton community near Kerguelen, on the other hand, has had millennia to adapt its species makeup to an annual nutrient surge. Unless we find a shortcut to millennia of adaptation, I suspect that this problem alone will significantly limit our ability to approach the efficiency of natural phenomena such as the Kerguelen blooms.
Posted by: Tim Feinstein | April 27, 2007 04:41 PM
Tim is right to emphasize the necessity of biomimesis in efficiently matching the demands of the mid-oceanbiotreme.
But on land, an entire industry sucessfully caters to the micronutrient demand of specific soil communities, producing major enhancements of biomass productivity by adding minor but well targeted amounts of ancillary trace elements to
ordinary fertilizers-it even works in their absence when farmers are too poor to afford adding NPK soil macronutrients in bulk- an element of the Green Revolution for which Joachim Winkler is justly celebrated.
A shortcut to millennia of adoption could well take decades of diligent colloid chemistry to cater to finicky phytoplankton, but in terms of productivity , it could just as well modestly outperform the local biotreme's available natural trace element diet as fail to approach it. At present the quantitative --and empirical--answer remains to be discovered.
Posted by: Russell Seitz | April 28, 2007 07:00 AM