A level of 1,000 ppm CO2 is apparently successfully used in greenhouses and that is the level which should be aimed for to stimulate plant growth with no adverse side effects to animals.

Putting anything anywhere should be done with appropriate controls. 100% water in a valley can also result in severe physiological changes for ABF.

Cheers
J



on 22/3/08 8:26 PM, Bob Beatty at wrote:

Ken,
There is little doubt fauna flora growth of all kinds can be enhanced by adding CO2. The concerns I have with this approach are twofold:
A) CO2 tied up in fauna flora is not tied up indefinitely it is only parked temporarily (I note the request below was not to sequester CO2 but to "manage" CO2. The current systems manage it pretty well do they not? Why the need for change?).
B) CO2 collected say in a valley can get to lethal levels pretty quickly for the passing air breathing fauna (ABF). We must not lose sight of the fact that CO2 is a waste product for ABF. Increasing levels of CO2 result in physiological changes that include acidosis, dyspnea, headaches, bone loss. These effects kick in from 7,000ppm and become very severe at 70,000ppm.

Pumping CO2 into a valley will inevitably lead to leakage and is unlikely to provide a satisfactory solution to disposing of large quantities of CO2.

However, there seems to be a much better alternative.
Both fauna and flora in the sea benefit from increasing levels of bicarbonate ions which forms by dissolving CO2 in water. From what I can determine the sea is effectively a bottomless pit for absorbing CO2.
The following web references are worth reading in appreciation of this point:
1) https://www.grisda.org/origins/06088.htm
Quote "Experiments that my graduate students and I have conducted indicate that one can, at least temporarily, nearly double the rate of coral growth by raising the temperature 5ºC or by increasing the carbonate ion content of sea water. What relationship this might have to past rates of coral reef growth remains to be investigated. Nevertheless a number of facts indicate that coral reef growth rates may be much faster than some of the slower estimates reported in the literature. Our present knowledge does not preclude rapid rates of development; some factors definitely facilitate it."
2) https://links.jstor.org/sici?sici=0024-3590%28199905%2944%3A3%3C716%3ABAPCG%3E2.0.CO%3B2-P&size=LARGE&origin=JSTOR-enlargePage
Abstract. The addition of 2 mM bicarbonate to aquaria containing tropical ocean water and branches of Porites porites caused a doubling of the skeletal growth rate of the coral. Nitrate or ammonium addition (20 uM) to oligotrophic sea-water caused a significant reduction in coral growth, but when seawater containing the extra bicarbonate was supplemented with combined nitrogen, no depression of the higher growth rate was evident. We infer that (1) the present dissolved inorganic carbon (DIC) content of the ocean limits coral growth, (2) this limitation is exacerbated by nitrate and ammonium, and (3) adding DIC increases coral calcification rates and confers protection against nutrient enrichment.
3) https://www.liveaquaria.com/general/general.cfm?general_pagesid=207

Growth rates of aquatic plants are strongly correlated with availability of carbon and the plant's affinity for carbon uptake. Studies have shown that plants with the greatest carbon affinity have the greatest growth rates, whereas those with lower carbon affinity have correspondingly slower growth rates. Because carbon availability is normally the limiting factor to growth, addition of CO2 to a planted aquarium will always result in large increases in growth (assuming other critical elements are not lacking).

4) https://epswww.unm.edu/facstaff/zsharp/505/carbonates2.htm
Essentially all of the productivity occurs in the shallow ocean.  Light carbon is preferentially incorporated into organic matter, enriching the residual dissolved carbon in 13C.  If the organic carbon in the shallow ocean was isolated from the deep ocean, it would eventually oxidize, with no net change in the d13C value for the TDC of the shallow ocean.  In fact, there is a very efficient mechanism for removal of organic carbon from the shallow to deep ocean, called the biological pump.  When organisms die, they fall through the thermocline into the cold deep oceans by gravitational sinking.  Thus, there is a constant removal of light carbon from the surface ocean leaving the residue enriched in 13C (figure).  This steady state enrichment is called the Œbiological pump¹.
5) https://www.nature.com/nature/journal/v201/n4917/pdf/201416a0.pdf

Two main pathways of carbon dioxide fixation have been demonstrated in marine invertebrates, the carboxy-lation of propionate to form succinate in the oyster1, and the carboxylation of pyruvate to form malate in flat-worms. The presence of enzyme systems capable of using carbon dioxide for synthetic purposes has been established in representatives of 14 phyla of animals, and many micro-organisms. Evidence continues to accumulate in support of the idea of Krebs that carbon dioxide is an essential compound in the metabolism of all cells. It has been stated often that if the citric acid cycle is to provide intermediates for biosynthetic reactions, fixation is necessary to replenish the supply of acids.

I guess the most relevant information on this subject of recent time is the paper by Em Prof. Lance Endersbee

https://www.ilovemycarbondioxide.com/pdf/Global_climate_change_has_natural_causes.pdf

In particular his Figure 2 shown:-

What this tells us is that sea temperature is the ONLY driver of atmospheric CO2 levels. Everything else is interesting/costly/time consuming, but only a side show.

Interestingly, Endersbee says there is evidence that surface sea temperatures are starting to fall again. This should result in lower Mauna Loa CO2 readings in the near future.

I am waiting with interest.

Best regards,

-- 
Bob Beatty BE FAusIMM(CP), Principal, BOSMIN
76-78 Hayes Ave, Camira 4300, Qld, AUSTRALIA
WWW: https://www.BOSMIN.com