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