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> In APD V2 #1123, Cliff Lundberg <cliff at noevalley_com> wrote:
> > Is there a technical term for this opposite of allelopathy?
> David Wheeler replied:
> Yes: mutualism.
David is correct, but I just had to jump in here. ;-)
Even "parasitism" is mutualism. The specific form of mutualism
where both species tend to benefit (possibly not requiring an
obligatory relationship) is "symbiotic mutualism" or "synergistic
If I recall from 10 years ago, there were five categories of mutualism.
I can look them up if anyone cares.
charleyb at cytomation_com
Stephen Pushak <teban at powersonic_bc.ca> wrote:
> Sorry to dash cold water on you guys plans to gather anecdotal data on
> allelopathic competition in plants however I figured you'd want to be
> aware of the scientific work which has been done in this area.
> <snip, arguments>
Hear, hear!!! This came up in APD years ago, and I was too scared
to talk. Even in the recent threads, I didn't want to make waves. <g>.
However, since I didn't broach the argument, I'll just throw weight
behind Steven. ;-)
In addition to his arguments, allelopathic compounds are much
more heavily employed by terrestrial plants in very arid climates
when very small margins are adequate to outcompete neighbors.
In humid or wet environments, plants evolved other mechanisms
such as growth rate, growth habits, different morphology, etc.
Since aquatic environments are all the way at the end of the
"evolve other means" spectrum, it has always seemed to me that
allelopathic compounds would be a "waste" of energy since so
many of these plants exist in moving water, where their efforts
are wasted (the chemicals don't remain where the plants are).
Even in lakes the water movement is *tremendous* from thermal
movement or wind/waves (and most bodies of water have
true circulatory patterns).
Second, allelopathic compounds are very effective in arid
environs because the net effect is a toxic reaction by the
neigboring plant (same or different species). In these arid
environments, the toxic reaction has full effect because the
neighbor must expend valuable water resources to
flush its system. In aquatic environments, this toxic effect
can very quickly and easily be diluted by the nearly infinite
supply of water.
Further, the battle in terrestrial systems is usually sub-terranean,
but aquatic plants typically rely less upon root systems so the
aquatic allelopathic battle must also in the water column with
more "wasted" surface area in play (much higher toxin output
needed with less effective neighbor targetting).
While I admit I do think about it now and then to explain
problems in my tanks I don't understand, and these threads
of discussion are plausible, the only (real) place where toxins
build up in aquatic systems allowing favor to one species over
another is probably in our tanks.
charleyb at cytomation_com