"Stoutman" .@. wrote in :


between NH3 and microbe population. They state (as I have) that the
concentration of the nitrifiers (bacteria) depends on the rate
(increased rates yield increased concentrations) of NH3 production.
The faster the rate (and thus the greater the concentration) the
higher the population of both microbes (nitrobacter and nitrosomonas).

You're incorrectly inferring that a high rate of production means a high
concentration of free NH3. The article is saying that bacteria will
increase their population density in response to an increase in the
availability of their food source. This is natural and to be expected.

Here's the quote:

"The concentration of nitrifiers depends upon the rate of NH3
production in the surrounding environment. The faster the rate, the higher
the population of microbes."

This says nothing about the concentration of measurable NH3 or the effect
the amount of measurable NH3 has on the overall conversion of NH3 into NO3-
in a new system, only that in an established system were the production of
NH3 is high the population of bacteria found using it as a food source will
also be high. In either an established low rate or a high rate environment
the amount of measurable NH3 is likely to be the same, ~0 ppm. We are
talking about fledgling cultures while the article is talking about mature
ones.

Here's another quote for you... I managed to dig it out of an article
published in the Plant and Soil journal in 1972.

"Summary: ...ammonium concentrations in excess of 200 ppm N
reinforced population imbalances conductive to accumulation of nitrite over
time in mixed cultures of Nitrosomonas europaea and Nitrobacter agilis.
Nitrate production proceeded at a low, linear rate characteristic for a
nonproliferating population, indicating a bacteriostatic effect of ammonium
or free ammonia on growth of Nitrobacter rather than an inhibitory effect
on nitrite oxidation."

I guess it is a direct effect after all.



You are missing the entire point as to why these bacteria are
metabolising NH3 and NO2- in the first place. This process of

This point is moot to the topic being discussed.

Either way it was merely a misuse of terms on my part. I fully understand
WHY nitric bacteria do what they do. I was not referring to a greater
demand for metabolic energy. A greater need for resources would have been
a more appropriate term to use in that context.



I'm not sure which bacteria (nitrobacter or nitrosomona) consume the
most o2.

I'm not sure either; it was just a guess or a suggestion at a possible
reason for lack of a documented explanation at the time.



Hopefully the previous poster can
produce some referenced material to clear this up.

Doubtful

What is the point of such a glib attitude in a community where the aim is
the sharing of experience and knowledge?

Is it merely to polish your own ego?