[Ink]

Siamo davvero sicuri che non servono differenti forme di carbonio?

leggete qua:

Rohwer and colleagues recently have published two provocative papers that attempt to link DOC levels with bacterial population levels in the holobionts of certain corals, and ultimately to the health of the corals themselves (Kuntz, 2005; Kline, 2006). Treatment of encrusted fragments of Montastraea annularis, Agaricia tenufolia, and Porities furcata in a controlled laboratory setting with 5 mg/L (= 2 ppm of C) of lactose, a disaccharide (see Fig. 1), killed most of the A. tenufolia specimens over 30 days, but did not cause any increased mortality vs. control for the M. annularis and P. furcata samples. However, a similar 30-day experiment with 25 mg/L of lactose (= 10 ppm of C) led to almost complete mortality with the M. annularis and A. tenufolia of course, but P. furcata remained unperturbed. Extension of this experimental protocol to other sources of carbon led to similar results. Mannose (a monosaccharide, see Fig. 1) at 25 mg/L (= 10 ppm of C) was particularly lethal to P. furcata, but not to M. annularis. Starch (a polysaccharide, see Fig. 1) at 25 mg/L ( 10 ppm of C) on the other hand, posed no threat to P. furcata but was deadly to the M. annularis samples. The resilience of P. furcata to all insults (except mannose!) was not unexpected, as this coral has adapted to life in far-from-pristine environments that suffer wide fluctuations in temperature, sedimentation and salinity. With this exception noted, these experiments, for the first time, provide unambiguous evidence for coral mortality as a consequence of exposure to carbohydrates that are related to components of DOC in the oceans.

DOC sta per "dissolved organic carbon", in pratica il carbonio che noi forniamo, non quello contenuto nelle cellule in sospensione (POC= particle organic carbon)(plancton), che rappresenta solo il 3% circa.
"Holobiont" è l'insieme di microrganismi che vivono sul corallo (spero di aver detto correttamente...)

Qui il link completo: http://www.advancedaquarist.com/2008/8/aafeature3