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The intersection of water and agriculture. Jean-Marc Faur è s UN Food and Agriculture Organization Rome, Italy. IPIECA biofuel water workshop, Rome, 9 November 2010. Outline. How the world is fed: agriculture, food and water Water scarcity and the role of agriculture - PowerPoint PPT Presentation
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The intersection The intersection of water and agricultureof water and agriculture
Jean-Marc Faurès
UN Food and Agriculture OrganizationRome, Italy
IPIECA biofuel water workshop, Rome, 9 November 2010
1.How the world is fed: agriculture, food and water
2.Water scarcity and the role of agriculture
3.Trends and prospects for water and agriculture
4.The agriculture-water-energy interface
5.Concluding remarks
Outline
Water requirements: why so much for agriculture ?
Needs(liters/p./day)
min max
Drinking 2 4
Domestic needs 40 400
Food 1000 5000
1. How the world is fed: agriculture, food and water
Water needed for crop production
Water requirements of major food products
Water requirements of major food products
CommodityWater requirement
(l/kcal)
Grain 0.4
Chicken 4
Beef 5
Main sources of food supply(Global average, 2002)
Energy requirements for human diet
1 kcal ≈ 1 liter of water
Rule of thumb #1:
Source of water in food production
Which water are we talking about ?
• “Green water”: rainwater stored in the soil and available for biomass production:
• 75,000 km3/yr
• rainfed agriculture
• “Blue water”: freshwater from rivers, aquifers and lakes:
• 45,000 km3/yr, 12,500 “available”
• irrigated agriculture
• cities, industries
• aquatic ecosystems
• .....
August 2006
114
654
1080
239
787
1505
1692
907
219
Areas in green: agriculture mainly under rainfed
Areas in blue: agriculture mainly under irrigation
Circles depict total crop depletion
Distribution of rainfed and irrigated agriculture
2. Water scarcity and the role of agriculture
Why irrigation ?
• Provides water for crop productions in regions where rainfall is not sufficient for agriculture
• Allows for double or triple cropping where climate allows for a single crop per year and intensification where land is scarce
• Reduce uncertainty and vulnerability to climate vagaries
• Allows for investment in other farm inputs: seeds, fertilizers, crop protection
• Allows for selection of (expensive) high value crops
Irrigation in the world today
• 300 million hectares
• 70% of all freshwater appropriation
• 20% of cultivated land
• 40% of agricultural production
• 60% of cereal production
Agriculture
69%
Industry
21%
Cities
10%
About 50% of available water resources is already used
Industry
4%
Cities
3%
Agriculture
93%
Abstraction Consumption
Agriculture is the main user of water
3. Trends and prospects for water and agriculture
Main driving forces today
• Water scarcity and increasing concern for environmental sustainability• Competition for water • Environmental claims• Pollution
• Demography• Reduced demographic growth rate• Urbanisation, changes in diet preferences
• Trade and globalisation
• Climate change
Sources of growth in developing countries
(2005/07 – 2050)
Arable Land Expansion
21%
Cropping Intensity
10%
Yield increase
69%
Harvested area increases 2005/07 – 2050
0
200000
400000
600000
800000
1000000
1200000
1400000
1600000
1800000
World(2005-07)
World(2050)
Developingcountries(2005-07)
Developingcountries
(2050)
Industrial +Transitioncountries(2005-07)
Industrial +Transitioncountries
(2050)
1000
ha.
Irrigated
Rainfed
Increase in irrigation 2005-2050Unused irrigation potential
Increase of area equipped for irrigationin 2050
Area equipped for irrigation in2005/2007
sub-Saharan
Africa
Near East
North Africa
Latin
America
South Asia East Asia
160
140
120
100
80
60
40
20
0
Changes in irrigated land and accompanying water withdrawals
Total Renewable water resources (cubic km)
Areas equipped for irrigation2005 / 07(Million ha)
Change in areas equipped for irrigation 2050
Irrigation water withdrawal 2005 / 07 (cubic km)
Change in water withdrawal 2050
Pressure on water resources due to irrigation in 2005 / 07
Pressure on water resources due to irrigation in 2050
World 42000 287 11% 2711 10% 6% 7%
Industrial countries 9000 44 0% 367 -7% 4% 4%
Transition countries 5000 23 -1% 212 -1% 3% 4%
East Asia 8600 85 14% 714 11% 8% 9%
South Asia 2300 81 6% 819 11% 36% 39%
Near East / North Africa 600 29 23% 314 9% 52% 57%
sub Saharan Africa 3500 6 40% 97 36% 2% 4%
Latin America 13500 18 34% 187 39% 1% 2%
4. The agriculture-water-energy interface
Projections for biofuel production
Water requirements of biofuels
crop
Fuel product (energy density: Bio-
diesel 35 MJ/l Ethanol 20 MJ/l)
annual obtainable yield in l/ha (indicative)
I/R
Evapo-transpiration in litre / litre
fuel (indicative)
Irrigation waterwithdrawn in litre
/litre fuel (indicative)
Sugar caneEthanol (from sugar)
6000 I/R 2000 1333
Sugar beetEthanol (from sugar)
7000 I/R 786 571
CassavaEthanol (from starch)
4000 R 2250 -
MaizeEthanol (from starch)
3500 I/R 1357 857
Oil palm Bio-diesel 5500 R 2364 -
Rapeseed / Mustard
Bio-diesel 1200 R 3333 -
Soybean Bio-diesel 400 R 10000 -
with 2 500 litres of water, we can:
• feed one person for one dayor• drive 15 km on biofuel
Rule of thumb #2:
Impact of bio-ethanol production on water
Source: Hoogeveen et al. 2009
• Rainfed agriculture: • Pressure on land resources
• Irrigated agriculture: • Pressure on water resources
Impacts of biofuels
NAS (2007): water and biofuels in the US• Currently a marginal additional stress on water at the
regional to local scale. • Significant acceleration of biofuels production could cause
much greater water quantity problems depending on where the crops are grown (incl. already depleted aquifers).
• Water quality already affected due to large amount of N and P required to produce corn.
• Future increases in the use of corn for ethanol production may translate in considerable increase in harm to water quality.
"Sweet Substitutes"Crude oil prices above 30 US$/bbl drive world sugar prices
0
10
20
30
40
50
60
70
80
Cru
de o
il p
rices in
US
$/b
bl
0.0
2.0
4.0
6.0
8.0
10.0
12.0
raw
su
gar
pri
ces in
cts
/lb
Crude oil (spot WTI)
Sugar (NYMEX-11)
Data: Nymex and EIA, J. Schmidhuber (2005)
Sugar-oil : the price link
5. Concluding remarks
Conclusions
• World water system already under heavy stress due to agriculture and other uses: China, India, already facing serious water constraints
• Agriculture main water user (70%)
• Future water demand for agriculture in the rise
• Climate change likely to result in increased demand for irrigated water
• Bioenergy likely to add to pressure on water:• depending on type of crop• depending on farming system: rainfed/irrigated• depending on region• through secondary effect on other productions
“Check-list” on water and biofuel
1. Understand which water we are talking about, and impact of biofuel production on
• land
• water
2. Assess the direct impact both on the quantity and quality of water
3. Assess indirect impact through price of major commodities and substitution effects
4. Seek win-win options through where competition for land and water is low
Thank You
www.fao.org/nr/water