On Sun, 15 Jan 2012 19:14:17 -0500, Frank wrote:
I'd also post in rec.gardens for someone there who knows more plant
biochemistry than me, but the urea in urine is no different from urea
used in fertilizer. Sometimes pure ammonia is injected into soil as
fertilizer and as you point out, water will hold it there.

I switched the sci.chem to rec.gardens. Thanks for the advice.

Googling for a comparison paper of urea fertilizer and urine, I found
this interesting paper from the Journal of Agricultural and Food
Chemistry, 2007, 55, pages 8657-8663 titled:
"Use of Human Urine Fertilizer in Cultivation of Cabbage - Impacts on
Chemical, Microbial, and Flavor Quality".

Interestingly, as you intimated, they found that the urine was as good or
better than the commercial stuff.

More interesting to the point, they recommended 'no more than 6 months'
storage of the collected urine! I'm amazed as everything else I read said
that the urine should be used within 24 hours because of ammonia (gas)
formation.

I'm sure it works - but - I want to better understand the whole process
so that the maximum nitrogen gets into the compost as usable nitrogen and
not vented to the atmosphere as ammonia.