[permaculture] A Golden Opportunity
David
david at h4c.org
Fri Dec 14 02:14:13 EST 2007
Norris,
Norris Thomlinson wrote:
> Last week I posted a short series on my blog about the need (or lack
> thereof) for nitrogen-fixing plants in small plots where the residents
> recycle their urine into the garden. Based on Martin Crawford's figure of
> one pee (half a litre) containing about 5.6 grams of nitrogen, and using
> his numbers for nitrogen demand of different food forest canopy plants, I
> calculated that one person's annual urine should meet the nitrogen needs
> of 4100-5100 square feet of forest garden.
>
> You can read the full post at:
> http://farmerscrub.blogspot.com/2007/12/nitrogen-fixers-vs-liquid-gold.html
>
"One adult on an ordinary diet will produce from 100 to 250 grams of
feces per day. On a vegetable diet, an adult will produce from 300 to
400 grams per day. (Respectively, 0.22 to 0.55, and 0.66 to 0.88 pounds
per day.) Feces are usually neutral to slightly alkaline in pH, 24% to
27% TS [total solids] (dry weight), with a C/N [carbon-nitrogen ratio]
of 6 to 10, nitrogen 4% to 6% of TS, VS [volatile solids] is 85% of TS.
Normal values for urine are 1 to 1.6 liters volume per day, average pH
6.0, 4% to 6% TS, with a C/N of 0.8, nitrogen 15% to 18% of TS, VS is
72% of TS. (That's 1.06 to 1.69 quarts volume produced daily). Every
liter of urine weighs about 1,020 grams. Every quart of urine weighs
about 2.9 pounds." [The Complete Biogas Handbook, p 69.]
*Substance*
*%N*
*%C*
*%H**2**O*
*Comments*
Human, feces
4-6
73-75.0
reported variations
feces
5.0
40.0
74.0
median
mixed
10.9
26.0
92.0
median
urine
15-18.0
95-96.0
reported variations
urine
16.5
13.0
95.0
median
[Ibid, p 37]
I hope the table (just above) survived...
d.
--
David William House
503-678-5162 (home)
503-206-1001 (cell)
"The Complete Biogas Handbook" www.completebiogas.com
"Make no search for water. But find thirst,
And water from the very ground will burst."
(Rumi, a Persian mystic poet, quoted in Delight of Hearts, p. 77)
More information about the permaculture
mailing list