Transcript World Food Production

World Food Production
Some definitions
• Tonne – 1000 kg or a metric ton – ton 2240 lbs
but everywhere in the world but US uses metric
and ton is pretty standard for 1000 kg
• Hectare – ha – an area 100m x 100 m (slightly
larger than a football field)
• Kilo-Calorie – measure of food energy – in food
refers to the energy capable of heating 1 kg of
water 1 degree celsius. In scientific language we
now use the joule – equal to 4.2 kilocalories
In fifteen years, the famines will be catastrophic
and revolutions and social turmoil and
economic upheavals will sweep areas of Asia,
Africa and Latin America. The collision is
inevitable. The famines are inevitable.
From “Famine 1975!” William and Paul Paddock 1967
July 21, 2011
On Wednesday, the United Nations declared
famine in two southern Somalia regions.
A UN definition of famine entails that at least
20 percent of households face extreme food
shortages, acute malnutrition in over 30
percent of people, and two deaths per 10,000
people every day.
From The Atlas of Food
Growth in global cereal production
Source Godfray 2010
Source Godfray 2010
Source Hall et al. World Fish Center
Why Famine 1975 didn’t happen
• World food production increased faster than
the human population
How does food production increase?
• Total yield = area planted times yield per area
• Increase in land used
• Increase in yield per area
– Better genetic strains of crops
– Increased inputs
• Fertilizer
• Water
• Pest control
Yield per area of US crops
World per-capita cereal production, 1951–1997.
Dyson T PNAS 1999;96:5929-5936
©1999 by National Academy of Sciences
Per-capita cereal production by world region, 1951–1997.
Dyson T PNAS 1999;96:5929-5936
©1999 by National Academy of Sciences
Foodgrain yield per acre
in india
Cereal Production( Tonnes)
450,000,000
400,000,000
Brazil
India
Tanzania
US
350,000,000
300,000,000
250,000,000
200,000,000
150,000,000
100,000,000
50,000,000
1960
1965
1970
1975
1980
1985
1990
1995
2000
2005
2010
8
Cereal yield (Tonnes/Ha)
7
Brazil
6
India
5
4
Tanzania
US
3
2
1
0
1960
1970
1980
1990
2000
2010
Area Planted (Ha)
120,000,000
100,000,000
80,000,000
60,000,000
Brazil
India
Tanzania
US
40,000,000
20,000,000
1960
1965
1970
1975
1980
1985
1990
1995
2000
2005
2010
Amount of increase from 1961-2009
Yield
per HA
Area
Total
Output
Brazil
2.6
1.8
4.8
India
2.7
1.0
2.8
United Republic of Tanzania
1.4
4.1
5.6
United States of America
2.9
0.9
2.6
How were the increases in yield per ha
achieved?
Photosynthesis
• Plants convert
sunlight to
sugars by
biochemical
magic
What do plants need
A seed (or seedling)
Light energy
water
Carbon dioxide (air)
soil
Is that all?
Brian Bue’s wife’s farm
Palmer Alaska
You need sunlight and HEAT: a growing
season
Nutrients
Weed control
Pest Control
The plant food system
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Seed
Soil
Water
Nutrients
Sunlight
Temperature
Air
Protection from weeds, pests
Can food production be sustained
• Look at each of these inputs -- can it continue
forever?
The plant food system
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Seed – loss of genetic diversity
Soil – soil erosion
Water – limits for irrigation potential
Nutrients – are we running out
Sunlight – doesn’t seem to be a problem
Temperature – probably not a problem
Air – lots of CO2
Protection from weeds, pests – development of
resistance
The green revolution
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Genetic improvements in cereal grains
Synthetic fertilizers
Added use of pesticides
More use of irrigation
Most impacts were in Asia
Largely credited with preventing world famine
The production of animal protein
• Wild capture
– Capture fisheries – 80 million tonnes
– Bushmeat – no estimates but small
• Grazing
– Primarily beef and goats
– Small proportion of world total animal production but very large
portion of earth is grazed
– Some significant aquaculture - shellfish
• Plant food inputs
– Almost all chicken, pork, US and European beef
– Significant aquaculture (e.g. farmed salmon)
• Animal feed inputs
– Primarily fish into livestock and aquaculture
The future of food production
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Has the green revolution peaked?
The impact of climate change
The role of genetically modified organisms
The environmental costs of past and future
increases in food production
– Clearing forests
– More fertilizer, pesticide and water
Study Questions
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How many kcal are available per day for people in the richest countries?
How many kcal are available per day for people in the poorest countries?
How much has world production of major grains increased since 1960?
What form of livestock meat has increased the most since 1960.
What was the primary reason that the famines forecast in the 1960s did not happen?
What were the two primary mechanisms that world food production increased from 1960 to 2000?
What are the four primary ways the yield per area planted was increased?
What is the world per capita per day production of major grains and cereals (in KG).
What was the Green Revolution and where did it have the biggest impact?
Rank in order of yield per area planted the US., sub Saharan Africa, India and China.
What is the major difference in how food production was increased between Brazil and the U.S?
List the necessary conditions for plant growth.
What fraction of global cereal production is used as animal feed.
Readings
• Famine 1975: a historical perspective on
concern and an introduction to apocalyptic
literature
• Godfray: a recent review of potential food
production
• Kaufman: overview of agriculture
The end
• Extra slides follow
Godfray, H. C. J., Beddington, J. R., Crute, I. R., Haddad, L., Lawrence,
D., Muir, J. F., Pretty, J., Robinson, S., Thomas, S. M., and Toulmin, C.
2010. Food Security: The challenge of Feeding 9 Billion People.
Science. 327: 812-8818.
Millstone, E., and Lang, T. 2008. The Atlas of Food: Who eats what,
where and why. University of California Press, Berkeley.
World cereal yield, 1951–1997.
Dyson T PNAS 1999;96:5929-5936
©1999 by National Academy of Sciences
World cereals: prices, stocks, and donations, 1960–1997.
Dyson T PNAS 1999;96:5929-5936
©1999 by National Academy of Sciences