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Urine as fertiliser - Research - Its as good as commerical fertilisers with no hygene issues

Tue, 06/10/2009 - 14:18 — Chewbyka

I was recently asked to comment on an article in the National Geographic (attached below) about using urine and ash as a natural fertiliser

Below is my response. Basically human urine is a fantasic source of water soluable nitrogen with traces of potasium, and phosphorous. Urine has an average NPK ratio of 10-18:1-2:3-5 depending on which research you read (basically depends on what you eat)

I'd suggest if you have not already look at you own outputs and how they fit into a sustainable system you do now ;o)

M

[Start]
...
Hats off to Finnish researchers for carrying out valuable scientific based research

  • Back in 2004[1] Finnish researchers showed that urine fertilisation produced similar or slightly better results that commercail fertilisers when used on cucumbers. They also stated that none of the cucumbers contained recordable enteric microorganisms (no hygene threats)
  • In 2007[2] Finnish researchers agian showed that urine fertilisation produced slightly higher growth and biomass than conventional ferilisers when used on cabbages. They also stated that there was no nutritional difference between the urine and commercially fertilised plants and no hygene threats
  • Now in 2009[3] Finnish researchers are showing that urine produces similar results to commercial fertilsers in tomatoes (the NG article does not actually state this unfortunatly, but if you read between the lines!) Interestingly this time they do state a nutritional increase over commercail fertilisers
  • Basically NG is packaging old news as new news and still hedging towards commercial fertilisers being the best. Is reporting on urine and ash an attempt to insinulate that urine on its own is not good enough and you can get  bigger and better by basic processing
  • Several things to query:
  1. Although not stated clearly in the NG article the urine used was aged (6 months@7DegC) so the amount of urea may have changed from that of fresh urine. What would be the results with fresh urine?
  2. How was the wood ash produced and does the method of production effect the results?
  3. What would be the results with other types of ash? (I cannot say I have a regular supply of birch ash!)
  • I have used urine by three methods: Dilution and immediate use (like Nick). Store for bulk use directly onto compost heaps. Apply fresh and neat to kill weeds (similar to salting). I neve store to dilute

Regards



M



Refs:



[1] Pure human urine is a good fertiliser for cucumbers
Helvi Heinonen-Tanski, Annalena Sjöblom, Helena Fabritius and Päivi KarinenDepartment of Environmental Sciences, University of Kuopio, P.O. Box 1627, FIN 70211 Kuopio, Finland. 2006-01-18



[2] Use of Human Urine Fertilizer in Cultivation of Cabbage (Brassica oleracea)––Impacts on Chemical, Microbial, and Flavor Quality
Surendra K. Pradhan*†, Anne-Marja Nerg†, Annalena Sjöblom‡, Jarmo K. Holopainen† and Helvi Heinonen-Tanski†
Department of Environmental Science, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio, Finland
Västanfjärd Municipality, Lammalavägen 105, FIN-25830 Västanfjärd, Finland. 2007-09-26
http://pubs.acs.org/doi/full/10.1021/jf0717891



[3] Stored Human Urine Supplemented with Wood Ash as Fertilizer in Tomato (Solanum lycopersicum) Cultivation and Its Impacts on Fruit Yield and QualitySurendra K. Pradhan*, Jarmo K. Holopainen and Helvi Heinonen-Tanski
Department of Environmental Science, University of Kuopio, P.O. Box 1627, FI-70211 Kuopio, Finland. 2009-08-03
http://pubs.acs.org/stoken/presspac/presspac/full/10.1021/jf9018917

[End]

 

Human Pee With Ash Is a Natural Fertilizer, Study Says
Charles Choi
for National Geographic News
September 18, 2009
 

When it comes to cultivating a green thumb, gardeners perhaps need only look to their urinals and fireplaces.

That's because human urine mixed with wood ash can help produce bumper crops of tomatoes, new research shows.

In
many ways the substances are natural complements, explained study
leader Surendra Pradhan, an environmental scientist at University of
Kuopio in Finland. (Related: "Urine Battery Turns Pee Into Power.")

Urine is high in nitrogen, while wood ash is rich in nutrients not found in urine, such as calcium and magnesium.

Human
urine and wood ash have each separately been used as fertilizer for
centuries. But until now, no one had explored applying them together.

Pee Productivity

The
scientists fertilized several groups of greenhouse tomato plants: one
with human urine and birch ash, another with commercial mineral
fertilizer, and another with just urine.

Plants fertilized with urine and ash yielded nearly four times more tomatoes than nonfertilized plants.

This
compared favorably with commercial mineral fertilizers, which produced
roughly five times as much fruit as nonfertilized plants.

To the team's surprise, urine alone produced a slightly greater yield than those of urine and ash together. (Read about sustainable-agriculture projects around the world.)

But
the urine-and-ash plants became larger than the other groups, and they
bore tomatoes with significantly higher levels of the nutrient
magnesium, which is key for bone, muscle, and heart health, among other
biochemical functions.

A group of 20 taste testers ranked tomatoes grown by all methods as equally tasty.

Simple Process

The best part of this type of fertilization is that "it is a very simple process," Pradhan said.

Urine can be collected from eco-friendly, urine-diverting toilets. Or farmers could just collect their pee in cans.

The
researchers estimate a single person could supply enough urine to
fertilize roughly 6,300 tomato plants a year—yielding some 2.4 tons of
tomatoes.

The farmer would just need to give plants ash three days or more after applying urine.

Pradhan and his colleagues are now trying to implement this idea in Nepal, where Pradhan is originally from.

Hormone Concerns

One
potential setback may be that pharmaceuticals and hormones excreted in
human urine—such as remnants of birth control pills—could negatively
impact crops, Pradhan said. For instance, such byproducts could promote
antibiotic resistance in local bacteria or get absorbed by the plants.

(Related: "Sex-Changing Chemicals Can Wipe Out Fish, Study Shows."

"However,
in small scales in a single family, the pharmaceutical residue present
in urine is very low and it can be acceptable," he said.

He
also argued that pharmaceutical and hormone residues have been in
animal-manure fertilizer for years, and that past studies have not
found them to pose a risk to agriculture.

Findings appear in the August issue of the Journal of Agricultural and Food Chemistry.

[End]