Overview on hunger, food and fertiliser Course 3 Unit 1 Extra Material 1 Teacher Mariska Ronteltap

2 Let's look at this anecdote: “In Uganda, banana trees are growing very well on old abandoned wastewater treatment ponds (as well as on filled pit latrines). The plants take nutrients from the excreta-based sludge in the ponds. People harvest these bananas at night secretly and sell them on the local market. The bananas are tasty and healthy but if consumers knew their origin, they wouldn’t buy them.” Story told by Ugandan MSc participants during ecosan summer school at UNESCO- IHE, Sept. 2007

3 Overview: benefits of using sanitised urine, faeces, greywater in agriculture (further details provided in Course 3 Unit 2) Ecosan productMain benefitFurther benefits Urine (sanitised)Fertiliser: nitrogen contentFertiliser: phosphorus content Faeces (sanitised)Soil conditioner: organic matter content (especially useful if converted to compost); improves soil structure Fertiliser: phosphorus content Greywater (sanitised)Water for plant growth (irrigation) -

4 Is this reuse of excreta in agriculture a new idea? Definitely not! You don’t have to look far and you find many examples where people are doing it or where doing it in the past  In Europe, “night soil” collection from the cities was common  use of excreta in agriculture. This came to an end when the production of artificial mineral fertilisers to boost crop yields was mastered (around 1850s). We used to have “sewage farms” in Europe – spreading sewage onto land (see next slide)  Banana trees growing in abandoned (filled) pits of pit latrines is very common in African countries So it’s not a new practice at all. Some of the older practices were not done safely though. In ecosan we do our best to practise this reuse in a safe manner.

5 Distribution of sewage from gravity outfall sewer via open trenches and irrigation ditches at "sewer farm". Sewage was conveyed from downtown Salt Lake City to sewer farms several miles northwest of the city for reuse and disposal. Sewage was distributed to crop areas by open conveyance systems. Source: Utah State Historical Society, Photo no. C-601 # Around year A “sewage farm” in the USA around 1900 Course 3 Unit 1

6 Multiple links between ecosan and improved health of people (particularly children) Source: Esrey et al. (2001), p. 58

7 Reminder (from Course 1 Unit 1): Half of all deaths of young children are associated with malnutrition Source: Data for An ecosan approach could have a direct impact on reduced diarrhoeal diseases (by improved sanitation) and reduced malnutrition (by use of ecosan products as fertiliser) ARI = Common cold; a viral infectious disease of the upper respiratory system Neonatal: in first 27 days of life

8 Hunger Map (in 2003) Source: Course 3 Unit 1 Orange, red and dark red areas: > 25% of the population is undernourished!

9 Future developments regarding hunger Hunger problem may well become even worse again, due to rising costs of many food items; some reasons for rising costs:  Increased demand from rising world population  Increased demand for meat and dairy products from countries where populations are getting wealthier (China, India) Meat-based diet requires more land, energy, water and fertiliser than vegetable-based diet! (should we all become vegetarians?)  Less land available for food production if farmers switch to biofuels production (e.g. US, Europe)  Rising oil prices (transport of food and fertiliser)  Increasing fertiliser prices (see Part B of this presentation)  Deteriorating soil fertility, land degradation  Possible climate change impacts, e.g. changing weather patterns, droughts, floods

10 Global risk factors for disease and premature deaths (% of DALYs) Source and further explanations: see next slide Child underweight for age Unsafe water, sanitation, hygiene Low fruit & vegetable intake Zinc deficiency Iron deficiency anaemia Vitamin A deficiency

11 Observations for previous slide (1/2) (provided by Håkan Jönsson) About half of the burden due to child underweight is in Sub-Sahara, and the main other part is in South Asia (the situation is about the same for Unsafe water & sanitation, zinc deficiency and Vitamin A deficiency, while iron deficiency and low fruit and vegitable intake are more evenly distributed). The Disability Adjusted Life Year or DALY is a health gap measure that extends the concept of potential years of life lost due to premature death to include equivalent years of ‘healthy’ life lost by virtue of being in states of poor health or disability (for more information on DALY see Appendix of presentation for Course 3 Unit 2). Full Reference: Lopez, A D, C D Mathers, M Ezzati, D T Jamison, C J L Murray. (2006) Global and regional burden of disease and risk factors, 2001: systematic analysis of population health data. Lancet (North American Edition) 367 (9524): FAO The state of food insecurity in the world. Eradicating world hunger – taking stock 10 years after the world food summit. FAO. Rome, Italy. Download: 2006ftp://ftp.fao.org/docrep/fao/009/a0750e/a0750e00.pdf

12 Observations for previous slide (2/2) “Of course can ecosan not solve all problems, just like good sanitation can not solve all water and hygiene problems. This graph shows more how much bigger our target group is than what it is if we just do sanitation. And if we can make ecosan function, it can do quite a bit. Also observe that about half of the under nutrition, zinc and vitamin A deficiencies are in Sub-Saharan Africa, where the use of fertilizers is really low – the second slide (see next slide) shows that the plant nutrient supply could be doubled if all urine and faeces is recovered. And it is the most poor that suffer from chronic hunger and one resource that these always have it that they do own their excreta. It is quite another thing however, if they have any land to put it on. But I do think that many of the hungry people are rural ones (have no data yet on this though) and for these more nutrients could be of great value.” on 25 Sept from Håkan Jönsson, Stockholm Environment Institute Course 3 Unit 1

13 Potential recycled nutrients as % of currently utilised chemical fertilizer nutrients Ref: Rockström et al., 2005 (p. 56)

14 Fertiliser use in sub-Saharan Africa is not increasing much unlike in other development regions (source: see notes on next slide) Fertiliser use in kg nutrient (N, P 2 O 5, K 2 O) per ha Sub-Saharan Africa South Asia South America All developing countries

15 Source of data for previous slide The graphic was taken from a presentation by Germer, Grenz, Sauerborn (2007) – see hohenheim.de/respta/info.phphttps:// hohenheim.de/respta/info.php The raw data on fertiliser use for all countries is available here: 7.pdf

16 Global estimates: Mineral fertiliser consumption compared to fertiliser value of wastewater  Yearly use: 135 Mio tons of mineral fertiliser  Conventional sanitation dumps 50 Mio tons of fertiliser equivalents - worth 15 Billion US dollar.” (Source: (1), shown on slide after next) (= 11 billion Euro with exchange rate of April 2007) Source: Million tons per year

Nutrients and Fertilizer Requirements A high percentage of the nutrient requirements for producing food crops (as an example: 250 kg of cereals) could be met by recovering the nutrients contained in urine and faeces. Source: (2) Source: (2), shown on next slide Course 3 Unit 1 17

18 References for last two slides (1) Werner, C. (2004): Ecological sanitation – principles, urban application and challenges. PP-Presentation. UN Commission on Sustainable Development, 12th Session - New York, April (2) Werner, C., Mang H. P., Klingel, F. Bracken, P.: General Overview about ecosan. PowerPoint-Presentation. Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ) GmbH ecological sanitation programme, Division 44 – environment and infrastructure Course 3 Unit 1

19 Fertiliser value of excreta (rules of thumb) – 1/2 If we take the N, P and K content of human excreta and assume it could sell for the same value as you get for N, P and K in inorganic chemical fertiliser, you can come up with rough figures on the fertiliser value of human excreta The following rule of thumb for the fertiliser value of excreta of one person (rule of thumb) were given by Thor-Axel Stenström at the ecosan seminar in Sofia, Bulgaria (April 2007):  Norwegian person: € 3.7 per year  Chinese person: € 2.0 per year Presumably because of lower calorific intake, and could also be that artificial fertiliser is cheaper in China than in Norway

20 Fertiliser value of excreta (rules of thumb) – 2/2 If we take the Chinese figures (from previous slide) for the whole world population of currently 6.5 billion, the total fertiliser value of all human excreta* would be € 13 billion (compare with value on earlier slide of € 11 billion). Such a figure can be useful to give an overview but of course the reality is somewhat different:  Cost of fertiliser also depends on availability, transport distance, the form that is in (urine is relatively diluted) and just general market forces  So just treat the € 13 billion as a rough estimate * Remember: excreted nutrients for a Chinese person in kg per person per year estimated as 4/0.6/1.8 for N/P/K – see Course 1 Unit 2 Part A

21 Example calculation: ”Fertiliser can pay for toilet” (for India) UDD toilet costs in India 4200 INR Excretion of nutrients/person, year N 4.55 kg, P 0.58 kg, K 1.27 kg 6 person family = 4 adults N 18.2 kg/yr, P 2.3 kg/yr, K 5.1 kg/yr NPK (%) costs 10 INR/kg, NPK (= %) costs 5.5 INR/kg Excreta worth INR/year Present value years 2-10= INR/kg Ref: Jönssson, et al Ecosan both Economical and Eco-sane. Water 21 (IWA International Water Associations monthly magazine) June issue p. 15. (slide provided by Håkan Jönsson)