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Re: Decaying plant mulm
On Fri, 5 May 2000, Tom Bates wrote:
> Does decaying plant mulm create any ammonia (um) release (even in
> minimal quantities) through the same Oxidative breakdown? If so, does
> this release occur over the duration of the decaying process or just at
> the beginning? Thanks in advance for any and all responses.
Plants contain proteins which can be digested to produce ammonium, but the
amounts are low compared to fish foods. I think plant material runs about
1.5% nitrogen on a dry weight basis (it's the nitrogen that ends up in
ammonium) while prepared fish foods are often about 8% nitrogen.
Plants can mobilize and reuse something like 50% of the nitrogen out of
old leaves. I suspect that the 50% that's left over in senescent leaves
or stems won't break down very quickly.
Whole plant material may be a different matter. Plants probably release
some water-soluble proteins soon after they die along with other water
soluble compounds. Those released proteins can be broken down fairly
quickly to produce ammonium, but only a portion of the proteins are
soluble. I've read that the nitrogen content of detritus is actually
higher than the nitrogen content of whole plant material and I assume that
is because a substantial part of the proteins are retained in the detritus
while a larger proportions of other compounds break down or are released
more quickly. That relatively refractory part of the plant proteins will
be converted to ammonium only slowly and some will almost never break
down.
Roger Miller