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Tom Kirchner
(ouzel) - MLife

Locale: Pacific Northwest/Sierra
Re: re:re: Burn TP on 06/20/2009 18:41:44 MDT Print View

"Sigh...and to think I used to live and hike in Oregon!"

Don't go back; It's been Californicated. :}

Tom Kirchner
(ouzel) - MLife

Locale: Pacific Northwest/Sierra
Re: Re: Burn TP??!! on 06/20/2009 18:45:05 MDT Print View

"Alright, I've got to ask. Doesn't it smell really bad when you burn TP? I've never even thought to do it."

Depends on your diet. Heavy on the meat and it smells like a burning tire; Vegetarian and you could smoke trout over it. ;-)

Tom Kirchner
(ouzel) - MLife

Locale: Pacific Northwest/Sierra
Re: TP research on 06/20/2009 18:58:28 MDT Print View

"I think they just mean that burying TP in a wetland is a Bad Idea."

It makes a lot of sense, Dean. Rapid and complete decomposition is generally aerobic, and a saturated soil is deficient in oxygen. Similar to peat bogs and well preserved wooden ships buried in sediment on the bottom of the Black Sea for ~2500 years. Also, in the case of Nova Scotia, it is cooler, as well as wetter, and both have an effect on decomposition rates. I have been burying and burning up in the Sierra for a long time and have found the decomposition process to be complete by the time I return 10 months to a year later. It could take even less time, but I have no way of knowing. But the Sierra is quite dry, definitely not a saturated soil.

"Can anyone explain why the filter thinks "fece$" and "p00p" are naughty words?"

I could take a stab at it, but I don't want to start another flame war or, worse yet, holy war. :-))

Lynn Tramper
(retropump) - F

Locale: The Antipodes of La Coruna
Re: TP research on 06/21/2009 14:20:38 MDT Print View

Details from the Discussion of Tasmanian paper:

4. Discussion and conclusions

Unbleached toilet paper does break down faster than bleached toilet paper and tissues. However, tampons stand out as being most resistant to decay, with the other products not strongly differentiated in their rates.

The sites that recorded the greatest decay rates were those that were warm, relatively dry and not acidic (Table 5). Breakdown of most products was well advanced within 6 months of burial at these sites. Microbial activity, measured by cellulase assay, was also greater at these sites (Bridle et al. unpublished data). Line (1998) found that the cellulose flocking used in disposable nappies decayed after 5 months in warm environments with neutral, fertile soils.

The independent variables that were incorporated in the models of decay (Table 4) are largely consistent with those that are associated with peat formation, which occurs in cold and/or waterlogged and/or acid places (Moore and Bellamy, 1974). Indeed the two sites that exhibited little decay after 24 months (montane moorland and western alpine) had organic soil profiles, while the others had mineral soils with a surface organic horizon of varying depths. The importance of cations (both measured directly, and indicated by pH), relatively dry soils and high temperatures in promoting disintegration has been noted for cotton strip assays in a wide variety of environments (Harrison et al., 1988). Higher decay rates during the late summer–autumn period than during the spring–early summer period has also been reported elsewhere (French, 1988). However, our data show that three sites (coastal eucalypt, subalpine rainforest, montane moorland) recorded greater decay in the cooler months than in the warmer months for the fertilised bags. There was no significant difference for decay within the same treatments but between times for any of the other sites. The difference in decay between the seasons is likely to be related to precipitation patterns during the sampling times. The autumn–winter bags were buried in 2000, while the spring–summer bags were buried in 2001–2002. There was a severe drought during 2000, and heavy summer rainfall during the spring–summer of 2001–2002. Rainfall is an important indicator of decay for fertilised bags (Table 4). The greater decay in the drier period is consistent with our model (Table 5).

Depth of burial is an important factor in decay at sites where soils freeze (Lawson, 1988). Under such conditions, there is a difference in decay with depth down the soil profile during the early summer, though this difference is not evident later in the season. Our data show depth of burial to be largely unimportant across all sites in Tasmania, but in wetter areas where water tables are within 15 cm of the surface, paper products are likely to decay more readily at 5 cm depth than at 15 cm depth. While decay may be slightly enhanced at shallower burial depths, access of faeces to native animals and transport of faecal bacteria may occur more readily at 5 cm depth than at 15 cm depth. The burial of waste under rocks at the soil surface does not increase decay, and is inadvisable from a public health point of view (Bridle et al., 2003).

It has been shown that the addition of nutrients via sewage sludge enhanced decomposition of cotton-strips compared to an untreated control soil (Obbard and Jones, 1993). The addition of both N and P to cotton strip assays in an Everglades marsh led to greater decomposition than was recorded for the addition of only one of the elements, especially where the strips were buried in the peat layer rather than in the water column (Maltby, 1988). There was no relationship between C/N ratios and breakdown success. This finding has also been documented for the decay of coarse woody debris in forest environments (Mackensen et al., 2003).

Research into the decay of coarse woody debris in forest environments showed temperature to be an important determinant of decay (Mackensen et al., 2003), but initial density of the wood was also important. These results can be related back to tampon decay, as tampons are much denser than toilet paper or tissues.

Mackensen et al. (2003) found a relationship between annual rainfall and decay rates, where decay was less at sites that received more than 1300 mm of rainfall. Ineson et al. (1988) suggested that that potential evaporation could be a good predictor of cellulose decay. We have developed a simple index of decay that is also based on temperature, rainfall and pH. The index is derived from two classes of mean annual precipitation (> 650 mm=1, < 650 mm=2), mean annual temperature (<13 °C=1, >13 °C=2) and pH (<4.5=1, >4.5=2). This index reconstructs the order of mean decay using all 6 month autumn–winter, 12 month and 24 month data (Table 5). A score of three on this index indicates that 2 years is insufficient for decay of all paper products buried in the soil, even when fertilised with faeces or urine. A score of six indicates a rapid dissolution of products, whether fertilised or not. This index may be exportable to other parts of the world.
4.1. Implications for management

A key question in deciding the implications for management of our decay data is the social and environmental acceptability of different periods of persistence of human waste disposal products in the soil. Social acceptability relates to the probability of excavating the evidence of a past faecal burial event, when undertaking preparations for a new event. This probability can be high in some well-used places (von Platen, 2002; authors unpublished data). Environmental acceptability relates to variation from the natural condition of the soil, which would obviously be considerable where deposits remain intact over several years. In the western alpine and high altitude moorland environments decay is extremely slow. In our judgement it is both socially and environmentally undesirable to continue to advise people to bury their wastes in these environments. This would not be a major imposition on walkers, as locations in these environments are usually in close proximity to forest or scrub vegetation, which provide more privacy than buttongrass moorland and alpine vegetation.

If anything is to be carried out, tampons are an appropriate target. Current MIB prescriptions request that tampons are carried out and not buried in the ground. As this is a simple and broad-ranging message with little public health risk to the walker, we suggest that the message is retained, despite the relatively successful decay of tampons, albeit after 2 years at some of the sites.

Walkers may place their wastes under rocks in alpine areas because they are reluctant to damage alpine vegetation by digging. We hope that the results of this research and those from our vegetation study (Bridle and Kirkpatrick, 2003) will convince them that it is less environmentally harmful to bury their waste than to leave it exposed.

Soil depth proved sufficient in parts of all our sites to enable burial of waste at 15 cm, as is suggested by the code. However, obstructions such as roots, rocks or very hard clay soil made it difficult to dig a hole 15 cm deep at some sites. Digging to that depth was impossible to severely challenging at most sites using plastic trowels of the kind sold in many outdoor stores. There is a need for prescriptions in the MIB guidelines on the strength and quality of trowels. Burial at 5 cm does present some relatively low chance of excavation by animals, compared to 15 cm, so the 15 cm recommendation in the code should stand.

Recent research which aimed to determine the impact of the addition of real faeces and urine on toilet paper decay, showed similar responses over a one year period to the results we have detailed above. Results from two extreme sites (coastal eucalypt and montane moorland) were consistent with the data presented in this paper (von Platen, 2002). While the presence of faeces may have allowed additional bacteria to survive in the environment, toilet paper decay was not significantly enhanced in a 6-month-period.

The above results suggest that the minimum impact bushwalking code should be amended to: (1) to recommend no disposal of faeces, toilet paper or tissues in treeless vegetation above 800 m in western Tasmania; (2) to emphasise that placement of waste under rocks causes more environmental harm than disposal by burial, even in alpine environments; (3) to emphasise that strong metal trowels are necessary to excavate holes for defecation in most wild places. The significantly longer decomposition times for tampons compared to toilet paper supports the current policy of carrying out tampons.

Guidelines should also advise walkers to choose their toilet site carefully. Choose a well-drained soil in woody vegetation rather than a poorly drained soil or peat in alpine or moorland vegetation.

The index we derived for predicting the speed of decay of human waste disposal products requires testing outside Tasmania, to determine its potential universality.

Dean F.
(acrosome) - MLife

Locale: Back in the Front Range
faecal burial events on 06/22/2009 07:50:45 MDT Print View

I think we should all now refer to our catholes by the correct scientific term, "faecal burial event." Or, perhaps, as an "FBE." The term cathole, after all, is pejorative towards felines.

P.S. Where did you find the complete paper, Lynn? Is it public?

If not, can you post results, not just conclusions? I'd like to know the decomposition rates for use as ammunition in future, ahem, "debates" with LNT zealots- I'm lookin' at YOU, Craig! :-) Plus, it may lead to a better understanding on my part about when it is OK to bury and when I need to pack out.

I don't bury at high-use sites, but then I generally avoid high-use areas in favor of solitude. I suspect that many here share this preference with me. I'm open to tweaking my other guilt-induction criteria regarding water table, rainfall, pH, etc. I guess I'll just have to pack the extra 0.0001-oz of pH paper. Oh, Wait! I could just Wipe With pH Paper! Multi-Use Victory! :-)

Edited by acrosome on 06/22/2009 08:06:54 MDT.

Lynn Tramper
(retropump) - F

Locale: The Antipodes of La Coruna
Re: faecal burial events on 06/22/2009 13:46:27 MDT Print View

Dean, the papers are not publically available, and I'm not quite sure how to post the graphs and tables. Maybe this is something I should learn how to do...?

Essentially all treatments were 'successful' by 24 months, with or without toilet paper, and with or without burial or urine.


The control treatment had significantly higher values
than one or more of the other treatments in 8 cases, and
significantly less in 10 cases (Table 4). The urine treatment
had significantly higher values than one or more of the other
treatments in 14 cases and significantly less in 7 cases
(Table 4). The dig treatment showed the reverse pattern with
3 and 14, respectively, while the dig and urine treatment had
8 in each class (Table 4). This differentiation by treatment is
significant (Chi-square ¼ 9.2, d.f. ¼ 3, P , 0:01), with the
urine treatment having more positive outcomes than
expected and the dig treatment having more negative
outcomes than expected.
There were no significant treatment effects in either of
the rainforest sites. Both alpine sites showed some effects.
In the western alpine environment the shrub, Monotoca
submutica, was positively affected by the dig and urine
treatment whereas bryophytes were negatively affected by
the treatments involving urine. In the eastern alpine
environment 6 non-woody taxa were favoured by urine
additions, and the scores on the second axis of the cover
ordination were significantly different between the urine
treatment and the rest (Table 4).
At the montane moorland site, the dominant shrub,
Melaleuca squamea, was favoured by the combination of
digging and urine, the shrub, Epacris lanuginosa, was
favoured by urine without digging, and the restiad,
Eurychorda complanata, was favoured by both the urine
treatments (Table 4). Bare ground was significantly greater
in the digging treatment than in the urine or control
treatments, litter cover decreased in quadrats where urine
was added and the scores on the second axis of the coverordination differentiated between the urine treatment and
the rest (Table 4).
The eucalypt forest sites did not individually exhibit as
many significant treatment effects as the montane moorland
and eastern alpine sites. At the montane eucalypt site urine
additions promoted native grass cover (Table 4). In the
grassy eucalypt forest urine also promoted native grass
cover, while it decreased litter cover (Table 4). The cover
ordination scores also indicated a strong effect of urine
additions (Table 4). At the heathy eucalypt site urine also
decreased litter cover, and on cover ordination axis 2 the
scores were significantly different between the control and
the urine treatment (Table 4). At the coastal eucalypt forest
urine increased the cover of the rhizomatous sedge,
Lepidosperma concavum(Table 4).

As you can see, the results are specific to Tasmanian flora, soils and weather.

Tom Kirchner
(ouzel) - MLife

Locale: Pacific Northwest/Sierra
Re: faecal burial events on 06/22/2009 18:38:56 MDT Print View

"Oh, Wait! I could just Wipe With pH Paper! Multi-Use Victory! :-)"

What if it turned the wrong color? ;}

On a more serious note, I think we are in danger of over analyzing one of the most basic biological processes in the biosphere. Decomposition occurs everywhere there is undecomposed organic matter. Throw together dead leaves and green vegetable matter and in a matter of months, given access to oxygen and a minimal amount of water, you will have compost. The basic substrate required is carbon and nitrogen, in roughly a 20:1 ratio, along with trace amounts of sulphur, phosphorus, calcium, etc, generally present in undecomposed organic matter. The process may be more, or less, efficient depending on how optimal the substrate ratios and temperature are, as well as availability of oxygen and water. It will proceed nonetheless, for the bacteria and fungi that decompose organic matter are present in every soil, everywhere and function over a wide temperature range. Fecal matter and TP are just one more feast for the little critters.

to feed the process.

Roger Caffin
(rcaffin) - BPL Staff - MLife

Locale: Wollemi & Kosciusko NPs, Europe
Re: Re: faecal burial events on 06/22/2009 22:14:25 MDT Print View

> we are in danger of over analyzing one of the most basic biological processes in the
> biosphere. Decomposition occurs everywhere there is undecomposed organic matter

A rare note of sanity in an otherwise weird debate. Thank you Tom.


Dale Wambaugh
(dwambaugh) - MLife

Locale: Pacific Northwest
Does a bear..... on 06/22/2009 22:49:37 MDT Print View

Do the best you can!

Ashes to ashes
Dust to dust
When I have to poo
I must, I must!

Stay away from the water, dig a real hole. Cover it up good and wash your hands.

I wonder if there is some enzyme that hikers could carry that would aid the process-- or would that just create more havoc? Maybe the enzyme could be incorporated into the toilet paper? Proably give us a rash....

Dean F.
(acrosome) - MLife

Locale: Back in the Front Range
Re: Re: Re: faecal burial events on 06/23/2009 05:03:37 MDT Print View

>> we are in danger of over analyzing one of the most basic biological processes in the
>> biosphere. Decomposition occurs everywhere there is undecomposed organic matter

> A rare note of sanity in an otherwise weird debate. Thank you Tom.

Not really. We aren't talking about science so much, except as a way to support an esthetic position. We are, after all, talking about leaving stuff sitting about decomposing in wilderness areas. I would propose that coming upon a decaying pile of leaves is esthetically discrete from coming upon a decaying pile of used TP. :-)

If I may be allowed to engage in behavior for which I have just criticized others- I will now indulge in BOTH a reductio ad absurdum AND a strawman attack, to whit: One could take Tom's comments to the ridiculous extreme that Craig mentioned- claiming that it is acceptable to dump ANYTHING that will decompose in the wilderness at will, even if it takes a long time to decompose and it unsightly. (I know that this is NOT what you were saying, Tom, but bear with me...) Obviously there is a level of acceptable dumping somewhere. We are just discussing where that line is, according to our individual beliefs. Craig puts the line at zero-tolerance. I do not.

Thus, yes, I would actually like to know how long it takes the stuff to decompose into unrecognizability, and what I can easily do to speed up the process.

Lynn- I ordered the paper through my library. I should have a copy in a few days. Hopefully it'll have more references that I can look up. Thanks.

Edited by acrosome on 06/23/2009 05:16:08 MDT.

Lynn Tramper
(retropump) - F

Locale: The Antipodes of La Coruna
Re: Re: Re: Re: faecal burial events on 06/23/2009 13:40:12 MDT Print View

" I ordered the paper through my library. I should have a copy in a few days. Hopefully it'll have more references that I can look up"

To me the upshot of those papers is that, long term buried toilet paper does *little harm* in most environments, and that the nutrient impact of leaving human waste (and whether to bury or not), depends on the specific conditions. Some organisms are actually *enhanced* by the extra nutrients or by having the soil turned, others are decreased, and yet others are not changed. And it all decomposes around two years.


To me, the issue is still one of aethetics more than environment. In a remote area, I will bury if convenient, or leave it where no one else is likely to find it for two years if not convenient (preferably exposed to full UV light for rapid deconatmination). In high use areas, there is alsmost always a supplied toilet of some kind, so I use that. It's really only the intermediate use areas where some discretion is advised!