LDOC - labile dissolved organic carbons defined in this paper as DOCs that have a turn over of a few hours to days.
From the article, the authors note a decoupling effect between DOC concentration and bacterial biomass.
"when the concentration or supply rate of DOC exceeds bacterial demand, mineral nutrients may become limiting."
So, PO4, NH3, and DOCs may be limiting in the Sargasso Sea. To test this they setup test areas adding PO4, NH3, and glucose (LDOC). Glucose additions increased bacterial biomass. Glucose + NH4 produced similar results (hinting nitrogen is not a limiting nutrient in this scenario). Glucose + PO4 results in higher levels than glucose and similar levels of solely adding PO4. Meaning PO4 is limiting.
Where does this play into the thread? Essentially, the argument is made that DOCs + PO4 + NH4 are needed for bacterial growth. LDOCs are more usable then DOCs by their definition since the average DOC is ~4100yrs old it is entirely possible that our reef tanks accumulate DOCs that are not readily usable and just need a push in the right direction.
I would stop thinking kreb cycle and look into bacterial biomass growth and assimilation of DOCs. Why cannot ethanol like glucose be a DOC?
I should also ask what are the questions?
From the article, the authors note a decoupling effect between DOC concentration and bacterial biomass.
"when the concentration or supply rate of DOC exceeds bacterial demand, mineral nutrients may become limiting."
So, PO4, NH3, and DOCs may be limiting in the Sargasso Sea. To test this they setup test areas adding PO4, NH3, and glucose (LDOC). Glucose additions increased bacterial biomass. Glucose + NH4 produced similar results (hinting nitrogen is not a limiting nutrient in this scenario). Glucose + PO4 results in higher levels than glucose and similar levels of solely adding PO4. Meaning PO4 is limiting.
Where does this play into the thread? Essentially, the argument is made that DOCs + PO4 + NH4 are needed for bacterial growth. LDOCs are more usable then DOCs by their definition since the average DOC is ~4100yrs old it is entirely possible that our reef tanks accumulate DOCs that are not readily usable and just need a push in the right direction.
I would stop thinking kreb cycle and look into bacterial biomass growth and assimilation of DOCs. Why cannot ethanol like glucose be a DOC?
I should also ask what are the questions?
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