20 DECEMBER 2014
Hacking a Toilet (at Utopiana in Genève)
At my Utopiana artist residency in Geneva I straddled with two challenges. One was to confront novice users to the handling of and reasoning behind a compost toilet. The other was to get the job done on a zero budget. In response I obstructed the existing flush toilet with a cardboard box, effectively rendering it obsolete. In its place I set up a bare bone bucket toilet with separate urine collection and the lactobacilli-biochar supplements. Step-by-step pictogram signage guided the user. The installation provoked strong feedback among fellow artists and visitors. Something I had hoped for. The mostly female clientele vehemently requested a solution for the simultaneous release of bodily solids and liquids. Basically it was a call to invest more into usability and comfort. After three weeks in operation the hacked toilet was drowned in flush water overflow in my absence during a wild house party. The cause is unknown to me. For the last week of my stay I relocated my improv Terra Preta toilet outside to the back of the house. Here I was able to answer nature’s call in winter wonderland with view onto Plantopic garden. Scenic shitting.
13 November 2013
Soil Feeder: Fermenting my Everyday
More than two months in the making, I just completed this short video. It is an attempt to bring the concept of human ecology onto the personal level. While rendering the process of reconnecting to the natural food web, I hope to capture something of the ritual and rhythm involved when one is subjected to the protocol and sequences of fermenting and composting.
8 SEPTEMBER 2014
Deploying Decomposition Probes
How does one know if biochar is really of good, lasting quality? Contrary to your regular barbecue charcoal, biochar is supposed to stick around pretty much forever. The point of high-temperature bicochar is to permanently stabilise the carbondioxyde from the biomass and prevent it from getting it back into the atmosphere where it ends up as greenhouse gases. Dr David Freudenberger suggested to me to measure the Decomposition Rate of my biochar for assessing its quality. If my charcoal dust can resist the decomposition process in my compost pile over several months, chances are it will survive the next centuries.
A simple way to moderate decomposition rates is to fill the material into a non-rotting, porous bag made from fiberglass fly mesh. This biochar bag with dried contents is accurately weighted before buried in a compost bin or soil. After several months of exposure to the elements, it is excavated, dried again and re-weighted to measure the loss of biochar. To account for variables I made five samples from each of the four test substances: pine sawdust and conifer cones, both in raw and carbonised form. Left to the ravages of ‘deep soil organisms’, I will recover my decomposition probes in four months from now...
16 AUGUST 2014
Cycle-and-Char Agri culture
Ancient civilisations already used biochar — carbonized biomass — as soil amendment. First nation people in the Amazon, Eastern Europe and in Asia roasted wood chips and leafy greens in ‘smothered’ fires where higher temperatures and low oxygen levels resulted in very durable and clean charcoal instead of ash. This charcoal acts a lot like humus. It is colonized by myriad microbes, fungi, earthworms, and other creatures. These soil organisms produce carbon-based molecules that stick to the charcoal and gradually increasing the soil’s carbon content. The carbon of decomposing organic matter which otherwise would escape into the air as greenhouse gases, is sequestered by the biologically active charcoal in the soil. Imagine the billions of tons of organic waste currently ending up in landfills and sewage treatment plants could be upgraded into biochar…
Research suggests that this carbon is captured and stored for hundreds — possibly thousands — of years, unable to contribute to global warming. This woodgas-derived, clean charcoal dust made from agricultural residues or renewable biomass, has a lot of promise as ‘carbon sink’. Every ton of this biochar in the soil is able of capture and hold at least 3 tons of carbon. The char also stimulates fungal communities (mycorrhizal fungi) that live on plant roots, scour surrounding soil for hard-to-find phosphorus, and deliver it back to their host plants. Microbial growth of all kinds is substantially improved. And so is the soil’s ability to hold nutrients until plants need them. Crops have been shown to grow 45 percent greater biomass on unfertilized terra preta soil versus depleted soil amended with chemical fertilizers.
16 JUNE 2014
Induction of Wood-Gas Stove
Two elements characterise Terra Preta soil making. (1) Fermentation is used to prevent the organic matter (from kitchen and toilet) from rotting and ammonifying and to retain its nutrients. (2) Clean, high-temperature charcoal dust (‘biochar’) is added that stops these nutrients from leaching out and provides habitat for valuable microorganisms due to its extremely porous constitution. Unlike ordinary charcoal, the real biochar doesn’t decompose and sticks around for centuries, therefore able to regenerate soil fertility. Even though biochar has been used in traditional agricultures for millennia scientifically it is not well understood yet. Certain is that pure biochar is able to remove CO₂ and permanently fix it (CO₂ sequestering) making soils to ‘Carbon Sinks’.
After focusing on self-sufficient fermentation in the first year, David Freudenberger and I have been looking at DIY biochar production. David’s expertise (and power tools) made it possible to convert an old metal trashcan into an up-lift kiln and a recycled paint bucket into a ‘retort’ — the closed container inside the kiln where the wood-gas conversion happens. The trick is to efficiently produce high temperatures (400°C minimum) so that the woody feedstock in the ‘retort’ container carbonises (pyrolyzes) which is very different from burning (combustion). With thorough instructions and a load of firewood from David I successfully carbonised my first batch of biochar from 2kg sawdust. My definition of ‘biochar success’ is fluffy, black flakes with an irresistible smoked scent. Feels good to produce something beneficial that certainly lasts much longer than myself…
8 JUNE 2014
Excavation of Treasures (Deep Harvest)
As winter is approaching it was time to excavate the fruits of the soil in my Terra Preta veggie bed. It is like an archeology into the activity of soil life and (human) nutrients that manifested into something edible. I was especially curious about the burdock which roots are drilling deep into the earths — as deep as my Terra Preta goes which unfortunately is only about 25 cm at this point. Below that is just bone-hard red clay. Conditions permitting, Burdock roots can grow twice as long. Luckily I never claimed to be a burdock farmer and will do more my homework before the next growing season. The dwarf roots were simmered into a yummy Kinpira Gobo: Mirin-sautéed burdock goodness. The food cycle is closed and it is time to pay tribute to all social organisms between me and my meal.
17 MAY 2014
The Dirty Beanstalk: Terra Preta Primer Session
I had the pleasure to organize an introductory Terra Preta workshop for twelve members of the the ANU Working Bees and the Gardening and Greening Crew. This hands-on three-hour long session came in two parts. First I showed the correlation of soil depletion, water scarcity, micronutrients deficiency, population growth and climate with how we manage (or not) our organic waste. In part two we collaborative manufactured sauerkraut since lacto-acid fermentation is a key element in the Terra Preta process. In this highly interactive session that took place in stunning autumn weather we looked beyond technical aspects of closing nutrients cycles by reconsidering the toilet as a 'Third Kitchen': a place that becomes part of an integral digestive system where we 'cook' — make vitality available — for the kingdoms of life that follow us in the food loop. The First Kitchen is situated in our households, the Second is embedded in our own physiology. Thanks Karina P.B.F. for setting up this fun workshop.
5 MAY 2014
(YR2) ‘Deep Fermentation’
This project on the natural human role in the cycle of vitality has entered its second year. After closing my first food loop in the last months (by devouring the mustard greens grown on my anthropogenic soil) I realised that I need to pay more attention to what happens in and between the different stages of digestion taking place in and outside my body. Rather than focusing on the material substrates in the ferment bottle and composting bin I need to pay closer attention to the relationships and influencing factors — the connections. The ecosophist Arne Naess reasons that this more respectful, profound approach allows for ‘self-realization for all beings’ which certainly should include lactic acid bacteria, millipede and protozoe. For a deeper questioning of my practice and to adjust my understanding with ever-changing conditions, I introduced a new tracking system that allows me to moderate my fermentation process more thoroughly. It is a back and forth process that I am recording with a Fermentation Log book as a more evolutionary way of research that changes with natural occurrences.
22 MARCH 2014
First, Deep-Rooted Harvest
Three sunny weeks and wonderful autumn weather did a lot of good to the veggies in my Terra Preta garden. The mustard greens (Japanese Mizuna salad leaves) were so large that they needed to be harvested right away. Comparing the plants from conventional and Terra Preta soil is visibly most revealing when scrutinising the roots. While the stems and leaves look similar, the root systems in the Terra Preta plants are visibly more developed. But beyond short term differences, my Terra Preta should be able to bear dozens of harvests and easily regenerate fertility with minimal amendment. We shall see.
2 MARCH 2014
Dark-Soiled Planting Pleasures
It was a perfect day for planting with the sky clouded up and light rain perpetually coming down. Manual planting is a fair amount of labor and without realizing I spent six hours in the garden. I never imagined how the quality of soil can influence the dexterity and work flow of planting. But I carried away in transplanting plants, allocating space, and my hands playing with the medium of true soil. What is true soil? These 'dark earths' are visibly teeming with soil life — bugs, critters, earthworms. So much so that I had trouble keeping out the chickens in recent weeks. Then there is this fluffy consistency. It has a peat-like touch, though more moist and responsive, which make it easy to poke and shape up. And when you water it all liquid is tracelessly absorbed right away. Digging in the dirt can be so much fun. Especially when the week-old, robust seedlings are tangibly keen to grow: Perky stems and leaves which make them easy to grab, sturdy root systems that seem confident to navigate the ground... How I can tell the difference? I have been planting on the other bed with the conventional soil which was not even half the fun...
1 MARCH 2014
Binary Planting: Nurturing Seedlings
The upper row of trays contains conventional local soil (slightly amended with organic fertilizer), the lower row of trays is filled with homemade Terra Preta. For comparison the seeds are mirrored in both rows. After a week the seedlings nurtured in Terra Preta are already up to 30% bigger than their counterparts.
23 FEBRUARY 2014
Binary Planting: Part Two
The heat wave and dry spell since in the passed weeks didn’t perrnit to put the seeds into the Terra Preta soil. But finally we had some hearty rains and last week I sowed eight kinds of autumn-proof veggies: Radish sprouts (かいわれ大根), burdock (ゴボウ), Japanese mustard (ミズナ), mustard spinach (小松菜), turnip (カブ, blue seeds), two kinds of welsh onion (ネギ), and Daikon radish (大根). Project advisor David Freudenberger checked out the Terra Preta substrate and gave the go ahead to the binary planting.
11 JANUARY 2014
Binary Planting: Part One
After seven months of careful ‘curing’ my Terra Preta substrate is ready for test planting. For comparison I created two beds: left side with my personalized and fermented soil, right side with local soil. Not sure how well the soil containing my body products will fare with tender vegetable plants. In any case, the soil found on location is so loamy, clayish and brittle in the hand that I decided to amend it with commercial NPK fertilizer — just to be fair. I don't want to be accused of torturing my crops...
31 DECEMBER 2013
Nurturing Seedlings for 2014
The passing year and the first seven months of The Nutrients Recovery Project was a very formative and foundational period. Through dedicated research, trial and error I am now able to lacto-ferment human excrements for eliminating pathogens (while holding on to the good bacteria) and stabilizing my nutrients. The fact that lactobacilli can be cultivated from scratch with simple means make this a self-reliant undertaking suitable for many urban contexts. This method works alternatively with rice, cabbage or adlay (Job's Tears) and therefore can be easily applied pretty much anywhere people want to return their excreted nutrients straight back to the soil (without contaminating water and air cycles). Currently I am deeply immersed in studying the ethic ("flee in disgust") and aesthetic implications for inviting interested individuals and institutions into this exciting open platform toward a personally internalized, envrionmental change.
4 NOVEMBER 2013
Employing 1000 Soil Workers
Making soil is a collaborative process. Without the magic of earth worms (on top of many other species) I am not able to make my personal nutrients palatable to plants. This past week I went to the home center and obtained a booster box with 250 grams of 'happy, healthy and hungry' vermins. If they like the food supply (incl. the charcoal dust) and their new boss (that's me), then their droppings will make for indispensible fertilizer.
12 OCTOBER 2013
Lactobacilli Cultivation for Busy People
Working constantly long, long hours at the office in the past month this was the ultimate reality check for this project. Using a simple recipe for cultivating lactobacilli cultures with molasses, sugar, milk and water I was able to multiply the fermenting power of my precious, homemade sauerkraut. The best thing is that this culture is at least as effective as pure sauerkraut juice according to my pH test that indicates strong acidity of 3.5. Thank you Herman Paulenz and Asrat Yemaneh for the magic formula that helps save my nutrients. I owe you both!
17 AUGUST 2013
TNRP Illustrations at the 1st Terra Preta Conference
This past week, I connected with Ralf Otterpohl, director of the Institute of Wastewater Management and Water Protection at Hamburg University of Technology where the 1st International Terra Preta Conference will take place later this month (Aug 29/30). As it happens, Professor Otterpohl found liking in the lineart illustrations on this website and kindly suggested to feature them at the conference. The visuals outline how we can move from a paradigm of linear thinking and dead-end material flows, to a cultural model that internalizes the importance of closed resource cycles. Harnessing human-derived nutrients to feed our ever-growing world population will be imperative and key is to make this major transition in a timely and dignified manner.
28 JULY 2013
Orchestra of the Wild: When social organisms ‘sing’
Last week I talked with my scientific advisor, Dr. David Freundenberger, about the aesthetics for composting and garden projects. We agreed that besides the sensitive method, presentation and affinity are important too. This project wants to explore alternatives to the scruffy community gardening or the technology-centred art gestures because they make most of us feel like outsiders.
Making my own sauerkraut and personal soil might not have much aesthetic appeal at first glance. Fermentation is often an obscure and slow process. So how can I make it into something tangible and noteworthy? Something that the rest of us might want to check out? Is it possible to become part of the ‘nutrients recovery experience’ itself (not just as nutrients donor)? While pickling cabbage or activating lacto-acid cultures isn't a very visible a process, it is pretty audible. Following ‘soundscape ecologist’ Bernie Krause , I started to record the hissing, bubbling and squealing that comes out of my jars and compost heaps. It is a way to leave the distant observer behind and get sucked into the moment, into experience itself.
5 JULY 2013
TNRP Travel Kit: Provision for Human & Critters
The other week I took a day trip out of town. Because every drop of urine is precious, I prepared my TNRP Travel Kit which satisfies my belly as well as the digestion of Social Organisms following me in the food loop. The beauty of collecting and pickling urine in a jug lies in the mobility it provides. International air travel will pose a challenge to TNPR but there will be a workaround. Promised.
29 JUNE 2013
Soil Lab now equipped with Recovery Tracker
Going forward I am able to record the saved nutrients onsite the Terra Preta Soil Lab with a custom-made chalkboard. In addition I named both compost piles. Soil bed no. 1 "Kurikuru" is dedicated to the Amazonian tribe that still cultivates this soil method. Soil bed no. 2 "Yorta Yorta" recalls the aboriginal tribe above Murray Valley (NSW) that created 'Terra Preta Australis'.
22 JUNE 2013
'Night soil' 下肥 and marketing of human fertilizer
Last week my friend Takagi-san in Kyoto mentioned to me that in Edo period Japan (Tokugawa 徳川 1603-1867) city dwellers sold human 'waste' as agricultural fertilizer. It was referred to as 'Shimogoe' 下肥 ("fertilizer from the bottom of a person") referred to as "night soil" in English (because in Europe the collection of human waste in times prior to flush toilets and sewage systems took place at night). Until the late 19th-century night soil was the principal source of fertilizer in Japan with a highly commercialised system for managing human waste. Most expensive was the night soil of the warrior ruling class and bureaucrats because their diet was most eclectic and little physical activity which makes for more valuable fertilizer… In some cases people traded veggies for night soil. Edo period Japan demonstrates that scarce resources bring out opportunities and creativity we can learn from.
Out of curiosity I calculated the commodity value of my urine. Since I am mostly doing office work, my urine contains more useful nutrients than others who do more physical labor. Therefore it can compete with urine from Edo Japan high society. Taking the current commodity prices for nitrogen, phosphorous, sulphate, potassium and flush water my 3 liter jug of fermented urine has a market value of 15 cents. This price doesn't include a carbon tax return which I can claim for my liquid gold: stabilised urine prevents greenhouse gases (like ammonia) through anaerobic fermentation contrary to ordinary urine that goes down the drain and sewage system.
15 JUNE 2013
Cooking for the critters next in the food cycle
I used to cook just for humans — mostly myself, my partners, sometimes for my guests. The Nutrients Recovery Project makes me cook for other, non-human species (kingdoms of life) as well. To cook also includes fermentation that can be understood as a form of preliminary digestion. Very powerful, natural 'digestives' are lacto-acid bacteria (LAB) that I want to wow with my cooking. LAB are the first 'social organisms' in the long cycle from my kidneys to the roots of the vegetables that I want to eat.
Because of their importance in this project I want to be able to multiply and feed LAB in more that just one way. Two weeks ago I started to cultivate lacto-acid bacteria with a method inspired by Korean and Japanese natural farming. It uses simply the residues of washed rice, water and milk. Now it needs to be seen in the weeks to come if this rice/milk-based LAB can handle the volatility and reactiveness of my urine...
8 JUNE 2013
Grinding charcoal powder
Charcoal in Terra Preta is most effective as a storage medium for microorganisms and moisture when it comes in powder form. The larger the surface area, the better. So I invited Broderick from the Working Bees to help me ground the biochar. Good fun!
5 JUNE 2013
Scavenging more charcoal
To be able to utilize all the nutrients released by my kidneys, I decide to establish a third Terra Preta bed. The problem is that I ran out of biochar. Luckily they did a 'controlled bush fire' on Black Mountain back in April which is close from to the ANU campus. So I spend most of my lunch breaks during the week scavenging another 150 liters of organic charcoal.
4 JUNE 2013
Adding the human elements
Now that the Terra Preta bed is ready — a nice carbon buffer, hungry for nitrogen — it is time to "add personality" to the soil, mine that is. Besides hair and beard clippings I watered Bed No. 1 with my first batch of fermented urine (acidity was an amazing pH 3.5). No odours, no fuss, just pre-digested human nutrients from my kidneys.
2 JUNE 2013
Preparing the Terra Preta substrate
Today I prepared the dinner table for critters and microbes that I want to convince to digest my human nutrients. I created a carbon buffer with forest litter (wood shreds), added charcoal powder, ashes, and inoculated (activated) the mix with living, local soil.
1 JUNE 2013
Soil Lab logistics
It's time to get the Terra Preta substrate started. Today I transported the missing pieces — 150 liters of charcoal powder and 5 liters of dolomite lime — from my home to the ANU Organic Garden . Despite the constant rain on this grey winter morning, it was time to celebrate the occasion and show strong colors.
26 MAY 2013
Building second compost bed alias ‘Yorta Yorta’
To ensure that I have enough 'carbon buffer' to counter-balance the nitrogen input from my urine, I built a second composting bed. We are digging in both wood frames to make sure the Terra Preta compost settles nicely and to prevent nutrients runoff in heavy rain. At the same time we excavated living soil (rich in organic matter and bacteria) to incubate the compost.
25 MAY 2013
Building first compost bed alias ‘Kurikuru’
I never expected for the project's scientific advisor, David Freudenberger , to get hands-on engaged in making this happen, but early on this Saturday morning David came down to the Soil Lab with his pick-up truck, power tools and a plan. Recycling wood from old playground equipment that we rediscovered in the back of the plot, we fabricated the frame for Terra Preta compost bed one.
22 MAY 2013
Shredding roots and weeds at the Soil Lab
This morning Matt and his crew from ANU Garden & Grounds arrived at the Soil Lab of the Organic Garden with their shredder. The plot cleaning with the Working Bees earlier this month resulted in heaps of plant clippings waiting to be mulched. The shredded material (called Forest Litter) will flow back into making Terra Preta .
21 MAY 2013
Planning the Soil Lab
With the plot cleared for Terra Preta, David Freudenberger took another good look at the site to advise me on setting up the composting beds. Since we're going to use only a small part of the plot for making Terra Preta , we allocated the sunnier parts for planting veggies.
19 MAY 2013
‘Wild’ sauerkraut rules acidity test with pH 3.5
Today's acidity testing confirmed the lacto-acid bacteria (LAB) power of homemade sauerkraut. My prime sample of fermented urine got as sour as pH 3.5 which eliminates all microbes (and pathogens) except LABs. The orange (SKB) of this litmus test is becoming my favorite color.
18 MAY 2013
Amazing ‘Working Bees’ help clear the Soil Lab
The Terra Preta Soil Lab is part of the ANU Organic Garden. There is a gardening & greening crew of students and volunteers called the Sustainability Learning Community "Working Bees" who meet twice a week to tend to the garden. Today the group brought together about 15 energetic Working Bees that helped with back-breaking weeding, hacking and shrub cutting. Thanks everybody for pitching in!
12 MAY 2013
Currently 12 kg of sauerkraut are in the pipeline
To ensure that I don't run out of inoculant — living lacto-acid starter cultures — I keep making sauerkraut. I am grateful that we have a totally under-utilised fridge in our college's tearoom that allows me to stockpile the precious social organisms . I used to cook just for humans up to now but The Nutrients Recovery Project makes me prepare food for many other species it seems.
8 MAY 2013
Project proposal accepted (hooray!)
Perseverance leads the way. After four months of explaining the value and integrity of The Nutrients Recovery Project to a number of services at the Australian National University (ANU), I got permission to produce Terra Preta soil on campus. Without the advise and mental support from David Freudenberger , I am not sure if I would have pulled it off. Our proposal found approval from the University Arborist, ANU Gardens & Grounds (university's Soil Yard), the Occupational Health & Safety's Work Environment Group, ANUgreen Sustainability Office, Facilities & Services, and last but not least, the Sustainability Learning Community's gardening & greening crew.
24 APR 2013
The anatomy of Terra Preta
One goal of this project is to explore the aesthetic possibilities of making human-derived soil. Today I turned the sunny veranda outside the HC Coombs building (where I work) into an impromptu video studio. With the input materials of Terra Preta , I captured a time-lapse and stop-motion clip for future reference.
14 APR 2013
Controlled bush fire delivers ash
Ash provides the calcium and magnesium in Terra Preta. When I read in the newspaper that there was a 'controlled bush fire' on Black Mountain next to ANU campus I knew what to do. Skip my original plans for the day, get working gloves and scavenge the still warm ashes from the forest ground...
12 APR 2013
First successfully fermented urine
About four weeks ago I started to use my homemade sauerkraut brine as the inoculant (activating culture) for fermenting urine. Today I pH-tested the first, 'fully self-determined' batch... The color indicator turned into a warm yellow which is around pH 4.0. Urine by default is pH 5.7 and turns alkaline (above pH 7) when untreated. When properly pickled, urine doesn't reek but instead gets a slightly sour smell.
23 MAR 2013
Bush fire from a decade ago supports TNRP
The differentiating key ingredient of Terra Preta is charcoal powder (biochar). Because of its porosity — that retains microbes and moisture — and its durability it becomes the everlasting, regenerable storage medium in Terra Preta soils. Terra Preta contains a minimum of five percent of organic charcoal and the question is where to source it. One summer day, when I hiked around Mount Majura in the inner north of Canberra, the answer came easily. Due to a bush fire ten years ago it is easy to find entire burnt trunks of gum trees around the hill.
15 MAR 2013
Inspecting the prospective Soil Lab
Besides the human nutrients, Terra Preta requires a gardening plot (small will do) and motivation to grow veggies. This is all available on the spacious, park-like campus of the Australian National University (ANU) in Canberra where my office is located. Being a novice at making soil, I searched at the ANU Fenner School of Environment and Society for a scientific advisor. I was very fortunate to find Dr. David Freudenberger , ANU research ecologist and lecturer, on whom I can rely when I have questions or get stuck. David not only brings his interconnected knowledge in a tangible context for me, but I can sense that as my teacher he wants me to succeed in this project. In this spirit David joined me over lunch today to check out an empty plot at the ANU Organic Garden that I want to use for Terra Preta composting. We looked at the topography, undergrowth and soil of the location to evaluate potential problems and hazards. Since I am planning to use urine in my compost, the ANU Facilities office asked me to manage the risks and have safety precautions in place.
24 FEB 2013
Making my own, homegrown sauerkraut
After relying too much on outsourced solutions (see previous post), I decided it was time to take things into my own hands. I went to the farmers market, got this big cabbage, shred it finely and mushed it into sauerkraut. After about three weeks of pickling, I will use the sauerkraut brine as inoculant (starter culture) for another urine fermentation test. And the tasty solids of the sauerkraut can be made into a yummie Boston Coleslaw or Munich Krautsalad.
21 FEB 2013
Experiments in the art of fermentating urine
Urine concentrates about 80% of the nutrients that the human body releases, which is why I am focusing my research and recovery efforts on this precious, golden liquid. Pivotal in this project is the mastery of lacto-fermenting urine that is possible in different ways, depending on context. I am spending many weeks experimenting with commercially available whey (milk serum), Effective Microorganisms (EM-1), pure strains of lacto-acid cultures from the lab, and every kind of sauerkraut (pickled cabbage) I can buy in stores. I am trying out different ways of incubation (activating the desired microbes through food, warmth and time) and vary the dosage of the inoculant (activated lacto-acid bacterias). Successful lacto-acid fermentation of urine is manifested through its increasing acidity (knocking out all undesired microbes) which I can measure with a simple pH test. Only after many weeks of constant failure (for example, the urine turns highly alkaline and smells like ammonia) I realise that the cultures available through retail seem for specialised use only and can't handle urine. Most surprising is that all the sauerkraut in Canberra stores (imports from Poland, Macedonia and the USA) is totally sterile and deprived of living lacto-acid bacteria. Therefore it is also not very useful for the microbial flora of my lower intestines.
18 FEB 2013
Milk jug donation with spirited gesture
After researching ways for stabilising urine I realise that lacto-acid fermentation in closed containers is the most sensitive approach. The anaerobic process eliminates CO₂ and green house gas emissions. The bottled fermentation provides a flexibility that makes The Nutrients Recovery Project viable in my everyday life. To minimize the ecological footprint, I asked my colleagues at work to collect used milk jugs on my behalf. In one instance, my colleague Wuqi Riletu added an artistic touch to his recycled jugs.
14 JAN 2013
‘Hay infusion’ for fermenting urine
To utilize the highly reactive urine responsibly as a source of nutrients in Terra Preta soil, one needs to stabilise it through fermentation (= controlled digestion). In my first experiments, I checked out an aerobic method that employs the manifolds of microorganisms that reside in dry hay. After simply soaking the hay in water for a week and feeding the microbes with banana and milk, they can digest urine in a bucket. The process suppresses odour emissions and ammonia but it is not practical for a full-time worker (me that is) without a garden at home.
28 DEC 2012
Hello, Canberra clay soils
Clay soils are hard to work with. Wet in winter and dry in summer, many plants struggle in them because of their coherent structure. Clay soils are packed with essential minerals but often lack organic matter. It appears that Terra Preta soil making is ideal in the bush lands of the Australian capital.
7 NOV 2012
Who are the ‘nutrients donors’ of this rooftop tree?
During an artist residency in Hong Kong, Markuz Wernli launched a petition to protect a rooftop tree on a vacant house. In a conversation with Michael Leung — an urban farmer and designer who is living next door to the tree — we speculated about how human urine might have caused this tree to flourish on concrete. This sparked the idea to launch The Nutrients Recovery Project.