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Food Resources
IB syllabus:
AP syllabus
Ch 13
Video – How to save the world, Food Inc
Syllabus Statements
• 3.5.1: Outline the issues involved in the imbalance in global food supply
• 3.5.2: Compare and contrast the efficiency of terrestrial and aquatic food production systems
• 3.5.3: Compare and contrast the inputs of materials and energy (energy efficiency), the system characteristics, and evaluate the relative environmental impacts of two named food production systems
• 3.5.4: Discuss the links that exist between social systems and food production systems
• http://www.worldometers.info/
Unequal food resources
• The methods of food production differ around the world
• Government policy and the climate of the area influence what is grown
• The type used depends on relative availability of land, labor, capital, and fossil fuels
Production Methods
Developed Countries– Industrialized agriculture depends heavily on
capital and fossil fuels
Developing Countries– Intensive traditional agriculture depends
heavily on labor– Shifting cultivation in tropical forests depends
heavily on land availability no fossil fuels– Nomadic herding depends heavily on land
Industrialized agriculture
Shifting cultivation
Plantation agriculture
Nomadic herding
Intensive traditional agriculture
No agriculture
Industrialized agriculturein developed countries
Intensive traditional agriculturein developing countries
Land
Labor
Capital
Fossil fuelenergy
Land
Labor
Capital
Fossil fuel energy
Shifting cultivation in tropicalforests in developing countries
Nomadic herding indeveloping countries
Land
Labor
Capital
Land
Labor
Capital
Distribution of food
• Enough food produced in the world for entire population to have 2,720 kcal per day
• Many areas no land to grow food or money to purchase it
• 982 million people living in poverty – actually a decrease in 20% from 1990’s
• ¼ of the world population consumes ¾ of the food
Population distribution in poverty
Region % in $1 a day poverty
Population (millions)
Pop. in $1 a day poverty (millions)
East Asia and Pacific 9.07 1,885.0 170.0
Latin America and the Caribbean 8.63 549.0 47.0
South Asia 31.08 1,470.0 456.0
Sub-Saharan Africa 41.09 753.0 309.0
Total Developing countries 982.0
Europe and Central Asia 0.95 460.0 1.0
Middle East and North Africa 1.47 306.0 4.0
Total 987
Influence of Ecology
• Developed countries in temperate areas – plants and soils conducive to growth of high yield cereal crops and livestock
• Soil fertility poor in tropical areas
• Livestock native to temperate areas in most cases as well
Influence of Socio-political factors
• Poverty is a self sustaining positive feedback process
• Governments in LDCs focus on exploitation of resources – Bananas in Costa Rica
• Governments in developed nations subsidize fossil fuels
• Support use of high yield green revolution crops• Research on and use of GMOs
Poverty MalnutritionDecreasedresistanceto disease
High deathrate forchildren
Decreasedenergy
Decreasedability
to learn
Decreasedability
to work
Shortenedlife
expectancy
Feedback loop
Food Type Kilocalories of fossil fuel input per kilocalorie of protein output
Feed lot beef 20-78
Pigs
Broiler chicken
Rangeland Beef
Sheep
Vegetables
35
22
10
10
2-4
First green revolution(developed countries)
Second green revolution(developing countries)
Major international agriculturalresearch centers and seed banks
DO NOT POST TO INTERNET
Crop
Cross breeding
Desired trait(color)
ApplePear
Offspring
Cross breeding
Best results
Newoffspring
Desiredresult
Selective breedingWe used to breed species for desired
traitsTakes multiple
generations
Now we just change the genes and create
GMOs
Phase 1Make Modified Gene
Identify and extractgene with desired trait
Identify and removeportion of DNAwith desired trait
Remove plasmidfrom DNA of E. coli
Insert extracted DNA(step 2) into plasmid(step3)
Insert modifiedplasmid into E. coli
Grow in tissueculture tomake copies
cell
gene
DNA
Plasmid
E. coliDNA
Geneticallymodifiedplasmid
plasmid
Phase 2Make Transgenic Cell
Transfer plasmidcopies to a carrier
agrobacterium
Agrobacteriuminserts foreignDNA into plantcell to yieldtransgenic cell
Transfer plasmidto surfacemicroscopic metalparticle
Use gene gunto inject DNAinto plant cell
A. tumefaciens(agrobacterium)
Plant cell
Nucleus
Host DNA
Foreign DNA
Phase 3Grow Genetically Engineered Plant
Transgenic cellfrom Phase 2
Cell division oftransgenic cells
Culture cellsto form plantlets
Transgenic plantswith new traits
ProjectedAdvantages
ProjectedDisadvantages
Need less fertilizer
Need less water
More resistant toinsects, plant disease, frost, anddrought
Faster growth
Can grow in slightlysalty soils
Less spoilage
Better flavor
Less use of con-ventional pesticides
Tolerate higherlevels of herbicideuse
Irreversible andunpredictablegenetic and eco-logical effects
Harmful toxins infood from possibleplant cell mutations
New allergensin food
Lower nutrition
Increased evolutionof pesticide-resistant insectsand plant diseases
Creation of herbicide-resistant weeds
Harm beneficialinsects
Lower geneticdiversity
Use of GMOs
2,000
1,500
1,000
500
0
Gra
in p
rod
uct
ion
(mill
ion
s o
f to
ns)
1950 1960 1970 1980 1990 2000 2010
Total World Grain Production
Year
Global Trend in Food Production
400
350
300
250
150
Per
cap
ita
gra
in p
rod
uct
ion
(kilo
gra
ms
per
per
son
)
1950 1960 1970 1980 1990 2000 2010
World Grain Production per Capita
200
Year
But… what does this show?
In use
Not usable
Arid land6%
Tropicalforest
8%
Cultivated
10%
Grazed
11%
Forests,arid
lands
14%
51%
Ice, snow, desertsmountains
© 2004 Brooks/Cole – Thomson Learning
Terrestrial vs. Aquatic Differences
Terrestrial
• Most food at low trophic levels
• Producers or Herbivores• Less energy loss
between initial input and level of harvest
Aquatic• Most food harvested at higher
trophic levels• Makes total energy storages
smaller• Due to tastes for fish / particularly
large predatory ones• Energy conversion in this system
is more efficient – sizes and lack of structural material in low trophic levels
• Initial amount of sunlight fixed is less efficient because of reflection and absorbtion by water
Systems of Production
1. Croplands- grains, 76% of worlds food
2. Rangelands- grazing meat production, 17% worlds food
3. Oceanic fisheries- 7% world food
Growth in production b/c technology
Challenge providing for future population
Food Production Systems
• There are many food production systems around the world
• They vary depending on the geography, sociopolitical dimensions, culture, needs of the area
• They also vary based on the characteristics of the food being produced
• We will look at a comparison of two of these many systems
• Many areas of the world are dependent on fisheries for food
100
80
60
40
20
01950 1960 1970 1980 1990
2000
Year
Total World Fish Catch
Cat
ch(m
illio
ns
of
met
ric
ton
s)
25
20
15
10
5
01950 1960 1970 1980 1990 2000
Year
World Fish Catch per Person
Per
cap
ita
catc
h(k
ilog
ram
s p
er p
erso
n)
800
600
400
200
01960 1970 1980 1990 2000
Year
80
70
60
50
40
30
20
Har
vest
(th
ou
san
ds
of
met
ric
ton
s)
Ab
un
dan
ce(k
ilog
ram
s/to
w)
Abundance
Harvest
Demersal (mostly bottom dwelling)
Hake
Haddock
Cod
Pelagic(surface dwelling)
Crustaceans Mollusks
Sardine Anchovy
Herring
Mackerel
Tuna
Krill
Shrimp
Lobster
Crab
Oyster Clam
Octopus
Squid
Fish Shellfish
Major Targets of Marine Fisheries worldwide
Spotter airplane
Fish farmingin cage
Trawlerfishing
Purse-seinefishing
sonartrawl flap
trawllines
trawl bag
Long line fishing
lines withhooks
Drift-net fishing
Fish caughtby gills
float buoy
fish school
Now we farm fish
• Fish is a major component of the human diet
• Some countries almost exclusively based on seafood – Japan
• With wild stocks being increasingly depleted, we are turning to fish farming for various reasons as an alternative
Figure 13-
31Page 303
Seafood type Kilocalories of fossil fuel input per kilocalorie of protein output
Marine Fisheries
Shrimp
Salmon
Cod
Ocean Aquaculture
Salmon cageculture
Salmon ranching
Seaweed
3-98
18-52
20
50
7-12
1
Advantages
Highly efficient
High yield in smallvolume of water
Increased yieldsthroughcrossbreedingand geneticengineering
Can reduceoverharvestingof conventionalfisheries
Little use of fuel
Profit not tired toprice of oil
High profits
Disadvantages
Large inputs ofland, feed, andwater needed
Produces largeand concentratedoutputs of waste
Destroysmangrove forests
Increased grainproductionneeded to feedsome species
Fish can be killedby pesticide runofffrom nearbycropland
Dense populationsvulnerable todisease
Tanks toocontaminated touse after about5 years
System 1: Rice-Fish Farming - China
• Fish farming in wet rice fields• In China, Han Dynasty plate (2000 years old)
shows fish swimming from pond to field• Ecological symbiosis in the system – fish
provides fertilizer to rice, regulates micro-climatic conditions, softens the soil, disturbs the water, and eats larvae and weeds in the flooded fields; rice provides shade and food for fish.
• Provides balanced food, reduced costs and labor, less use of chemicals in the environment
www.fao.org/DOCREP/005/Y1187E/y1187e18.htm
• Inputs – All fish food is in the system, small fish left behind as stock for next year rice requires input of small amounts of urea, N,P,K and optional lime or manure
• System Characteristics – uses native fish, polyculture using natural principles of ecosystem interaction, sustainable
• Socio-cultural - tenant farmers improve income, in china industrialization threatens its continued use
• Environmental Impacts – may use pesticides but generally less than alternatives, reducing CH4 emissions compared to normal systems
• Outputs – fish and rice, 2 rice crops per year
Norwegian Salmon Farms
• Norway and Chile produce 2/3 of the world’s farmed salmon
• 60% of world’s salmon is farmed
• High input system of penned fish in ocean areas or on land – depends on pellet food derived from wild caught fish
• High density high waste systems
Norwegian Salmon farms
• Inputs – need pellets for feed made from fishing for smaller fish in the ocean,
• System characteristics – monoculture – disease susceptible so antibiotics used, may selectively breed stocks, human manipulated
• Socio-cultural – farming operations provide local jobs, if effecting local fisheries that effects jobs as well
• Environmental Impacts – 100,000’s escape cultivation & threaten native fish, farmed fish less effective reproducers than natural but their offspring are more successful
• Outputs – antibiotics, nutrients causing eutrophication,
Fish change form
Fish enter riversand head forspawning areas
Grow to smoltand enter the ocean...
Grow to maturityin Pacific Oceanin 1-2 years
Eggs and young arecared for in the hatchery
Fry hatch in the spring...
Fingerlings migrate downstream
In the fall spawning salmondeposit eggs in gravel nests and die
NormalLifeCycle
Fingerlingsare released into river
And grow in the streamfor 1-2 years
Human capture
Salmonprocessingplant
Eggs are taken from adultfemales and fertilized withsperm “milked” from males
ModifiedLifeCycle
To hatchery
Food Production Systems are linked to social systems
• Modern US – Developed, high tech, high fossil fuel input– Value speed and convenience– Capitalism based revenue generation– Removed from food production so don’t see
negative results– We are willing to compromise environmental
health for the benefits now from pesticides, inorganic fertilizers, machine harvest etc.
Cropland
Irrigated farm land
Rangeland
Pasture
Forest
Barren land
Wetland
Urban area
4% 2% 6% 5%
17% of totalcommercialenergy use
Crops Livestock Food processing Food distribution and preparation
Food production
Think back to the rice-fish system
• Tied to asian cultures as a historical practice
• But asian culture is changing more cosmopolitan more movement to cities
• Could threaten this model system
• It is a form that keeps soil fertility high in areas with high population density this can be used on the outskirts to maximize production per area.
Can the green movement
• Swing our culture to sustainable food production?
• People interested in organic foods
• Green production – boutique types of grocers and restaurants
• Benefits the planet and trendy
Increase
High-yield polyculture
Organic fertilizers
Biological pestcontrol
Integrated pestmanagement
Irrigation efficiency
Perennial crops
Crop rotation
Use of more water-efficient crops
Soil conservation
Subsidies for more sustainablefarming and fishing
Decrease
Soil erosion
Soil salinization
Aquifer depletion
Overgrazing
Overfishing
Loss of biodiversity
Loss of primecropland
Food waste
Subsidies forunsustainable farming and fishing
Population growth
Poverty
Croplands
• Help maintain water flow and soil infiltration
• Provide partial erosion protection • Can build soil organic matter
• Store atmospheric carbon
• Provide wildlife habitat for some species
Ecological Services Economic Services
• Food crops
• Fiber crops
• Crop genetic resources
• Jobs
© 2004 Brooks/Cole – Thomson Learning
Done the right wayCropland can be very beneficial
And don’t forget the global trend in food production…
1950 1970 1990 2010 2030 2050
Year
0.20
0.25
0.15
0.10
0.05
Gra
in a
rea
per
per
son
(h
ecta
res)
• http://www.fao.org/nr/giahs/pilot-systems
• Food and agriculture organization of the UN