carbon assimilation

[detlef]

Hi Tom,

I might like to know if my general view of uptake pathways is right:

From report 4/05 I've learned that about half of all SAMs are capable of using HCO3-. There are only very few plants which need CO2 for survival since they can't uptake HCO3- at all, e.g. Tonina sp., Neaea sp., Eriocaulon setaceum etc. On the other hand there are plants like Anacharis, Ceratophyllum, Egeria, Najas, Vallisneria which can exist from HCO3- exclusively without any free CO2 in the water column. But all plants prefer CO2 over HCO3- and, if capable, start taking in HCO3- when CO2 gets low/deficient.

Anything wrong with this or would you concur?

Regards,
Detlef

 

[Tom Barr]

Re: carbon assimilation

That's fairly true, I am not sure because no one has done any studies on the more rare aquatic plants recently brought into the hobby, but they do not seem to be particularly good at tolerating low CO2.

But, good old java moss grows great, and all mosses only use CO2.
So....while it might seem true for some things, there are exceptions.

Only a few plants have really been looked at and they tend to be the wide spread common or weedy species with economic and ecological significance.

Regards,
Tom Barr