Vannressurser og matproduksjon. Wageningen Universitet, Irrigation Colombia, praksis Kenya/Turkana, FAO Egypt, DGIS

Transkript

1 Vannressurser og matproduksjon Wageningen Universitet, Irrigation Colombia, praksis Kenya/Turkana, FAO Egypt, DGIS

2 Hvor mye vann trenges for å produsere mat? Noen eksempler ( Bygg, hvete trenger cirka 1300 liter vann per kg Ris trenger cirka 3400 liters 5000 litres of water for 1 kg of cheese. En brød skive krever 40 liter med vann, med ost på kommer du på 90 liter 1 kg med kjøtt krever cirka liter med vann 4800 litres of water for 1 kg of pork.

3 Vannforbruk Matproduksjon er den største forbruker av vann. For å produsere en balansert diett; I gjennomsnitt trenges det 3 4 m^3 med vann for å skaffe oss 3000 kcal/dag/person Som er cirka 70 ganger mer enn de 50 l/dag/person til daglig bruk Jordbruket bruker cirka 69% av de globale vannforsyninger, 21 % går til industrielle formål mens 10% går til husholdninger.

4 Befolkningsvekst og behov for mer mat 9,2 6,2 Store deler av verdens matproduksjon foregår ved hjelp av kunstig vanning (irrigation) Vi hører stadig mer om knapphet på vann. Mer enn halvparten av verdens kornproduksjon blir brukt som dyrefør (Keyser et al, 2005 i UNEP; The environmental food crisis). Kanskje en lett måte å løse problemet på er å bli vegetarianer.

5 Bioforsk er involvert i vanningsprosjekter. Det som høres veldig ofte nå er at vi må øke den såkalte Water Use Efficiency, More crop per drop crop yield( kg) WUE = 3 water use( m )

6 Water use efficiency (WUE) The ambitions of the India s National Water Mission ( 2008) To improve WUE by 20%! How can this be achieved? Må det brukes andre, mer effektive vanningsmetoder, mindre vanntap i produksjonen Hvordan vannes nå, hvordan blir vanning praktisert. Kan metodene forbedres Dette er noe CLIMAWATER prosjektet ser på.

7 Hvordan vannes det, hva er infrastruktur i et vanningsprosjekt Fra dammen går det gjennom et system av vanningskanaler til jordene (1., 2., 3. nivå)

8 Losses to uneven water use along the canal (upstream/downstream problem) Tap i vanningssystemer Direct losses into open drains Evaporation from canals Direct losses from canals Losses due to deep percolation/past root systems

9 Improving WUE by improving irrigation systems The overall irrigation scheme efficiency (e o ) combines the irrigation efficiencies A scheme irrigation efficiency of 50-60% is good; 40% is reasonable, while a scheme irrigation efficiency of 20-30% is poor. It is not unusual to have overall irrigation efficiencies in the order of 40%.

10 Improving WUE by changing irrigation methods Different irrigation methods have different efficiencies Border/furrow irrigation Application efficiency (E a ) in the order of 60 % E a = vekst fordamping vann tilført

11 Sprinkler, drip irrigation Application efficiencies (E a ) in the order of 80 % 90 % pws.byu.edu/pas100/irrigati.htm

12 Agronomic practices and Water Use Efficiency Improvement of harvest index (ratio of marketable grain yield to crop biomass) However for most crops the limits are reached Agronomic practices Improvement of soil fertility, optimal fertiliser application, avoid land degradation, control plant diseases, tillage measures (mulching) Genetically modified crops (?!; drought/pesticides resistance, less fertiliser mm). This also especially for rainfed agriculture (see later) Introduction of new varieties or different irrigation methods to similar crops System of Rice Intensification (SRI) Introduction of new variety (Nerica/Warda)

13 Dyrkingsmetoder kan påvirke fordamping Ris tradisjonelt, rismarken står under vann. System of Rice Intensification (SRI), redusert evaporasjon; soil - kept moist but well-drained and aerated transplanting; singly, only one per hill instead of 3-4 together to avoid root competition, usually just 8-12 days old, with just two small leaves widely spaced to encourage greater root and canopy growth Achieving More with Less: A new way of rice cultivation World Bank toolkit ( ry/245848/index.html)

14 Bruk av grunnvann til vanning Mange borebrønner etablert til vanningsformål Ved vanlig vanning av ris (forsyning gjennom kanalsystem) er det tap til grunnvannet og som benyttes av borebrønn. Hvordan vil en overgang til SRI påvirke grunnvannsmagasin. Hvordan vil en reduksjon av tap i vanningskanaler påvirke grunnvannsmagasin.

15 Improving WUE by improving irrigation systems However!!!! 1. before setting out on improving irrigation systems, a good overview of present use is necessary because 2. Inefficient use of water for agricultural production at one location might at present be beneficial for others users located downstream or be of use for ecosystem maintenance. (Deep) percolation losses do recharge groundwater being used for tubewell irrigation (in the case of India) Tail end losses flow back to the river to be used downstream

16 What about rainfed agriculture LET IT REIGN: The New Paradigm For Global Food Security. Skrevet i oppdrag av SIDA av SIWI, IWMI, IFPRI, IUCN. Forfattere; mange, Hovedforfattere; prof Falkenmark/Jan Lundqvist, SIWI Det store potensialet for å øke matproduksjon er rainfed agriculture

17 Let it reign Today s food production involves a consumptive water use of altogether 6800 km3/yr (out of which 1800 are supplied from blue water resources). To feed humanity by 2050 on 3000 kcal per person per day will require an additional 5600 km3/yr, out of which a maximum of 800 will come from blue water resources. The 2050 column shows that the remaining 4800 have to be contributed from new green water resources (e.g. horizontal expansion) or from turning evaporation into transpiration (vapour shift). Data from [7].

18 Rainfed agriculture og muligheter Mye er mulig i Afrika. En del hendelser tyder på det. Utenlandske investeringer i landbrukssektoren i Afrikanske land Etiopia I alt 1.6 millioner hektar land er satt av til utenlandske investeringer i kommersielt landbruk (saudi-etiopisk, indisk, amerikansk) Kupp på Madagaskar delvis på grunn av salg av land (dyrking av mais) til utenlandske selskaper. Zambia, Angola andre

19 Andre muligheter? Kan vi gjøre noe selv? Saving water: From the field to the fork. Curbing losses and wastage in the food chain. By: SIWI, IWMI, Chalmers, Stockholm Environment Institute Losses and wastage may be in the order of 50 % between field and fork 1. Losses through inefficient harvesting, transport, storage and packaging, wastages in food processing, whole sale, retail, in households 2. Not all agricultural products that do not reach the dinner plate is wastage, but instead used for other purposes like feed, bio-energy, soil improvement One key message of the report: Make the food chain more efficient to save water

20 Eksempler på inefficient food chain

21 Andre saker. Kan vi gjøre noe selv?

22 Norske matvaner Dagsavisen Kjøtt konsum; dersom 50% av hver, blir det brukt 38.5 x x 4800 = liter eller m 3 med vann Legger vi til osten (17 x 5000) er det totale vannforbruket blitt m 3 Denne mengde hadde vært nok til å dyrke cirka 250 kg ris

23 Ikke spar på grillkosen spar på penger Rema 100 grillkampanje

24 Hvor mye vann trenges for å produsere klær? Noen eksempler Cotton Water footprint: 2700 litres for 1 cotton shirt. A pair of jeans weighing 1 kilogram needs litres per kilogram.

25 Nordmenn får bedre råd framover På grunn av sterk krone blir det billigere å importere mat, klær mfl., (Dagsrevyen ) Det er bra, så kan vi kjøpe mer klær. Men hva er konsekvensene av dette? Dressmann tilbud til 17 mai! Alle skjorter og slips Ta 3 betal for 2 Vi spanderer den rimeligste

26 The Nile Basin

27 Egypt, Nile Delta Johannes Deelstra pengeinnkrever

28 Egypt and water use Increasing population in Egypt -> increasing demand for water? Ethiopia, on average provides 80-85% of the annual discharge of the Nile, yet to date uses virtually none of it. Egypt and Ethiopia; conflicting interests Egypt plans to divert water from the Nile (New Valley Project) to the Western Dessert (5 10 km 3 yr -1 ) Toshka project Ethiopia plans to construct microdams (500 estimated 4 km 3 yr -1) Nile basin Initiative Playing Chicken on the Nile? The Implications of Microdam Development in the Ethiopian Highlands and Egypt s New Valley Project, by John Waterbury, American University of Beirut and Dale Whittington, University of North Carolina Chapel Hill

29 Increased water supply to Egypt One of the driving forces behind the start of the last civil war between the south and the north was the Jonglei Canal. This is an idea that has been around for a very long time. It was to be a canal to bring the water through one of the largest wetlands in the world, The Sudd, more quickly to the north and to Egypt. But those earlier plans did not include much improvement in the lives of the people of the South and along the proposed canal. Dr. John Garang, one of the leaders of the southern rebels wrote his Ph.D. on the Jonglei Canal. jonglei-canal-m.jp

30 The Great Man Made River, Lybia The nubian sandstone aquifer

31 The Great Man Made River, Lybia The GMR project - the world's largest engineering venture - is intended to transport water from these aquifers to the northern coastal belt, to provide for the country's 5.6 million inhabitants and for irrigation. Intended to be the showpiece of the Libyan revolution, Colonel Moammar Gaddafi called it the "eighth wonder of the world". There are four major underground basins. 1. The Kufra basin, lying in the south east, near the Egyptian border with an estimated capacity of 20,000km³ in the Libyan sector. 2. The 600m-deep aquifer in the Sirt basin is estimated to hold over 10,000km³ of water 3. Murzuk basin, south of Jabal Fezzan, is estimated to hold 4,800km³. 4. Further water lies in the Hamadah and Jufrah basins, which extend from the Qargaf Arch and Jabal Sawda to the coast.

32 The Great Man Made River, Lybia The 4-meter diameter conduit is about km long. This huge pipeline supplies water to the cities of Tripoli, Benghazi, Sirt and other settlements. The amount of water transferred daily is 6.5 million m3.

33 The Great Man Made River The criticts Fossil water cannot be renewed! Libya runs the risk of running out of fresh water supply at about the same time they will run out of the other underground resource oil, that would be a catastrophe. Already there is evidence that the GMR has begun to lower the ground water table in North-Western Libya, in the desert Tuaregs say some of their wells are drying out. With the same amount of money that will have been spent on completion of the GMR Libya could have built 12 dissalination plants. According to Adel Darwish (from a lecture given in Geneva on Water and Wars), a water war may start between Libya and Egypt: "Should geologists present the proof that mining water in Libya has a direct effect on the Nile bed the Egyptian army will try to put an end to the GMR".

34 BIOFORSK? Hva kan vi bidra med? Kan vi bidra? Hvor? Hva? Hvordan?

35 Bioforsk og utlandet, hva skal vi gjøre, hva trenges Våre erfaringer fra eksisterende prosjekter (inn og ut), nettverk Kunnskap som trenges; Hvordan å utnytte vannressurser optimalt(more crop per drop) med minst mulig miljø/klima belastning (modeller, COUP, Aquacrop, andre) vanningsmetoder, gjødselforbruk, jordarbeidingsmetoder (mulching), mm Hva er forekomst av plantesykdommer (klima) hvordan blir forekomst av plantesy kdommer under klimaendringer sykdommer av nye driftsformer Bruk av modern teknologi (JOVA /LMT liknende) andre Dersom vi synes vi kan, aktiv markedsføring, påvirkning både nasjonalt/internasjonalt, nettverkdannelse, mm Viktige momenter (India Afrika linken, GS/DU og bistandsaktuell, Bioforsk Afrika satsing) Fantasien sette grenser, det finnes begrensninger som kunnskap (satsing), interesse hos ansatte

36 Takk for oppmerksomhet Husk 1 kopp kaffe krever 140 liter med vann 1 kopp te krever 30 liter ned vann.