Ch. 12 Food Resources

APES

Fig. 12.1, p. 261http://www.time.com/time/photogallery/0,29307,1626519,00.html

How Food is Produced

• 14 plants and 9 animal species feed 90% of the world.

• This big three: wheat, rice, and corn• Which are annuals that need to be planted each

year• Beef, chicken & pork (includes milk, eggs &

cheese)• 2/3’s of the world relies on these grains and

meat products.• 2/3’s of the world does not eat meat• Fish and seafood 7%

Food Production

• Croplands: supply 77% of the world’s food -mostly produce grains using 11% of the world’s land area

• Rangelands: produce meat from grazing livestock, supply 16% of world’s food on 29% of the world’s land area

• Fisheries and aquaculture: Supply 7% of world’s food

Types of Agricultural Systems

• Industrialized (high input): agriculture uses large amounts of energy (fossil fuels) and energy, water, commercial fertilizers and pesticides to produce huge quantities of: a single crop or livestock, produces four/fifths of world’s food.

• An increasing number of animals are raised in densely populated feedlots, where animals are fattened up for about 5 weeks to four months and then slaughtered. They eat corn and never see sunlight. Produces water and air pollution.

Food Production in the USA

• Industrialized “agribusiness” controlled by large multinational corporations. No more “mom and Pop” farms.

• 18% of our gross national product, bigger than automotive, steel and housing combined.

• Since 1950 we have doubled yield without cultivating more land.

U.S. Agriculture

• Biggest industry in the U.S. – 18% of the GNP and 19% of all jobs in the private sector.

• 0.3% of the worlds farm labor force produces 25% of the world’s food and :

• U.S. residents spend only 10-12% of their income on food, while 18% is spent in Japan and 40 – 70 % in developing countries.

• Cost: 10 units of nonrenewable fossil fuel for every 1 unit of food : energy

• Plantation agriculture: primarily in tropical developing countries. Cash crops such as: coffee, bananas, and cocoa. Large areas of rainforests are cleared for this.

Fig. 12.2, p. 263

Industrialized agriculture

Shifting cultivation

Plantation agriculture

Nomadic herding

Intensive traditional agriculture

No agriculture

Fig. 12.3a, p. 264

Industrialized agriculturein developed countries

Intensive traditional agriculturein developing countries

Land

Labor

Capital

Fossil fuelenergy

Land

Labor

Capital

Fossil fuel energy

Fig. 12.3b, p. 264

Shifting cultivation in tropicalforests in developing countries

Nomadic herding inDeveloping countries

Land

Labor

Capital

Land

Labor

Capital

Traditional Agriculture

• Traditional (2.7 billion people in developing countries, provides one fifth of the world’s food)

• traditional subsistence farming: raising only enough crops and livestock for the family farm – shifting cultivation

• Traditional intensive agriculture: increased labor, fertilizer & water for the family and enough left over which can be sold for income.

Green Revolution

• Green Revolution: Change in agriculture, which lead to increased yield per unit of area. (before, increased yield came from expanding the cultivated area)

• 1. Planting monocultures of selectively bred or genetically engineered high yield key crops with emphasis on shifting from plant growth to seeds.

• 2. Using fertilizers, pesticides, & water to produce high yields.

• 3. Increases intensity and frequency of cropping.

Fig. 12.4, p. 265

First green revolution(developed countries)

Second green revolution(developing countries)

Major International agricultural Research centers and seed banks

2nd Green Revolution:

• Fast growing dwarf varieties of rice and wheat bred for tropical and sub tropical climates introduced in developing countries.

• The yields are 2 –5 times the traditional methods and it allows multiple cropping which:

• Protects biodiversity• Saves land from destruction• Needs fertile soil, water, & extensive fossil

fuels to run machinery to produce and apply ample inorganic fertilizers & pesticides.

Fig. 12.6, p. 266

Cropland

Irrigated farm land

Rangeland

Pasture

Forest

Barren land

Wetland

Urban area

Fig. 12.7, p. 267

4% 2% 6% 5%

17% of totalcommercialenergy use

Crops Livestock Food processing Food distribution and preparation

Food production

Livestock:

• Raising animals like cattle, horses, oxen, sheep, chicken & pigs to provide food, clothing, fertilizer, fuel, and transportation.

http://www.storewars.org/pressroom/

Livestock

• 20% of the world’s land is used for: grazing cattle and sheep.

• Cattle used for meat and meat products return fertilizer to land and graze on fallow fields.

• World meat production has increased 4 times, while per capita production rose by 29%

Livestock

• 12 – 15% of the methane in the atmosphere comes from cattle.

• Nitrogen in commercial fertilizer is converted to NO, a greenhouse gas.

• Nitrogen in manure escapes into the air as NH3, which contributes to acid deposition.

• Livestock produce 21 times more waste than humans and only ½ is recycled into the soil.

Traditional Agriculture:

• Interplanting which is growing several crops on the same plot (crop diversity).

• Polyvarietal: several varieties of the same crop.• Intercropping: 2 or more different crops that are

grown at the same time. These crops “help” one another.

• Agroforestry: crops and trees are planted together.• Roots are at different depths• Year around plant coverage protects soil from erosion• Different insects for each crop cut down on the use of

insecticides.• Weeds have trouble growing.• Higher yields for each crop are produced.

World Food Problems

• How much has food production increased? • World grain production between 1950-1990

has tripled.• Per capita production has increased by 36%• Average food prices dropped by 25%• Amount of food traded quadrupled• Population growth is outdoing food production

& distribution

Fig. 12.8a, p. 268

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

Fig. 12.8b, p. 268

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

Reasons for the slowdown in growth of per capita grain production.

• Population growth @ 1.2%/yr• Increased affluence which increases demand• Degradation and loss of cropland (due to erosion,

industrialization, and urbanization)• Little growth in irrigation since 1980• 10% decline in global fertilizer use• Population growth 8 billion by 2025 (6 billion in 1999)• This requires doubling the food production or 2% grain

production increase per year compared to a 1.1-% growth between 1990 – 1997. This is IF people have a meatless diet

• 2% per year growth between 1950 to 1990, .5% increase between 2000 and 2004

• How many people can the world support? It depends upon:

• Quality of life or cultural carrying capacity per person.

• Whether food production can be increased

• Length of food chain with grain and meat eaters.

Food and Sub Saharan Africa

• Per capita food production dropped by 30% between 1960 – 1994.

• Malnutrition and hunger related illnesses cause death for thousands each day.

• ½ of the population doesn’t have access to safe drinking water (cholera and dysentery result).

• Infectious diseases cause ½ of the deaths per year.

• Rapid population growth (1 million every 3 weeks 2.9% increase). This creates a young age structure pyramid.

Fig. 12.9, p. 269

Poverty MalnutritionDecreasedresistanceto disease

High deathrate forchildren

Decreasedenergy

Decreasedability

to learn

Decreasedability

to work

Shortenedlife

expectancy

Feedback loop

Food and Sub Saharan Africa

• Tsetse fly blocks development of agriculture (fatal disease in livestock and incurable sleeping sickness in humans).

• Severe soil erosion, nutrient poor soils, lack of water for irrigation, increasing desertification and deforestation.

• Political turmoil and wars cause reduced agricultural production and cause food storage and distribution system problems.

Undernutrition, malnutrition, and over nutrition

• Under nutrition: people who can’t grow or buy enough food for their basic needs.

• Less than 90% of the daily calories needed: chronically under nourished.

• Less than 80% of the calories needed: seriously under nourished. This causes mental retardation and stunted growth. This makes people susceptible to disease and affects 25% of children.

Malnutrition:

• low amounts of proteins, carbohydrates, fats, vitamins, & minerals. (Usually a low protein, high carbohydrate diets). Some people suffer from undernutrition and malnutrition. (most live in Asia)

• Diets low in iron cause anemia and this condition is found most often in Asia, Africa and Latin America

• Diets low in zinc and iron cause diarrhea, malaria and pneumonia.

• Diets low in iodine (seafood & soil) affects the thyroid gland, which controls metabolic rate.

Overnutrition:

• an excessive intake of food (especially fats).

• This accounts for two thirds of the deaths in the U.S. per year.

Producing enough food to feed the world.

• Enough food is produced, but it is not equally distributed due to differences in soil, climate, and political and economic power.

• The principal cause of hunger and malnutrition is poverty.

• Food Aid does not work because of corruption in the system, the food does not get to where it needs to go, also the people become dependent on it and fail to farm their own food and it increases their birth rate.

Environmental effects of producing food.

• Agriculture has a greater harmful impact on air, water, soil, and biodiversity than any other human activity. Degradation of irrigated and rain fed croplands and rangelands costs 42 billion$ in lost crop and livestock output.

• Soil erosion, desertification, salinization and water logging irrigated lands will limit producing more food

• Loss of water due to droughts means a loss of wild species that provide genetic resources for new foods and improve existing foods

Fig. 12.10a, p. 271

Biodiversity Loss

Loss and degradation of habitat fromclearing grasslands and forests anddraining wetland

Fish kills from pesticide runoff

Killing of wild predators to protectLivestock

Loss of genetic diversity fromreplacing thousands of wild cropStrains with a few monoculture strains

Soil

Erosion

Loss of fertility

Salinization

Waterlogging

Desertification

Fig. 12.10b, p. 271

Air Pollution

Greenhouse gas emissions from fossilFuel issue

Other air pollutants from fossil fuel use

Killing of wild predators to protectLivestock

Pollution form pesticide sprays

Water

Aquifer depletion

Increased runoff andflooding form land clearedto grow crops

Sediment pollution fromerosion

Fish kills from pesticiderunoff

Surface and groundwaterpollution form pesticidesand fertilizers

Overfertilization of lakesAnd slow-moving riversFrom runoff of nitrates andPhosphates fromFertilizers, livestockWastes, and foodprocessing wastes

Fig. 12.10c, p. 271

Human Health

Nitrates in drinking water

Pesticides residues in drinking water,food, and air

Contamination of drinking andswimming water with disease organismsfrom livestock wastes

Bacterial contamination of meat

Increasing world food production

• Increase crop yield?• Improve strains of plants and expand

green revolution technology to new parts of the world.

• Raise “harvest index” by increasing the photosynthetic product to go into seed instead of stems and leaves for wheat, rice and corn. The physiological limit is at 60%.

Increasing world food production

• Crossbreeding: selective breeding between plants to increase their size or yield. Limited to DNA that is available in that type of plant. (Like dog breeding)

• Genetic Engineering: Splicing a gene from one organisms (not limited to plants) and inserting it into a new plant to create new qualities

• The gene revolution: use of genetically engineered foods that are resistant to insects and disease, thrive on less fertilizer, make their own nitrogen fertilizer, do well in slightly salty soils, withstand drought, & use solar energy more efficiently.

• Usually crops need ample water, good soil, favorable weather, favorable temperatures, solar intensity, and day length. We can create crops that don’t this.

The Gene Controversy

Advantages• Less fertilizer• Less water• Resistant to disease,

insects, drought• Grow faster• Can grow in salty soil • Less spoilage• Better flavor• Less pesticide• Higher yield

Disadvantages• Irreversible and

unpredictable effects• Harmful toxins and

allergens in food possible• Lower nutrition• Can harm beneficial insects• Lower genetic diversity• Can create herbicide and

pesticide resistant insects and plants

Problems with the Gene Revolution

• Large corporations patent the GMO seeds so farmers cannot reuse their seeds from year to year. This has high costs that cannot be paid in developing countries.

• Yields may drop due to soil erosion, loss of fertility, increased salinity, becoming waterlogged, polluted from pesticides, nitrates from fertilizers and rapidly breeding pests that become resistant to pesticides.

Loss of genetic diversity and crop yields

• Crop varieties have decreased (97% in the U.S. from the 1940’s).

• Genetic uniformity increased the vulnerability of food crops to pests, diseases and harsh weather.

• Wild varieties usually reduce the need for yearly plowing and sowing which reduces soil erosion, which saves water and energy. Usually wild varieties are resistant to viruses and grow in colder and damper habitats.

• Storing seeds in seed banks are risky: seeds die and cannot be reintroduced because habitats have changed.

New foods?

• Winged bean and microlivestock (insects) are potential sources of proteins, vitamins and minerals.

• Rely more on perennial crops, which are better adapted to regional soil and climate conditions than animal food crops. Use of perennials reduces energy use, water, soil erosion, and sediment water pollution. This would reduce profits of agribusiness due to the sale of annual seeds, fertilizers, and pesticides.

Cultivating more land?

• 30% of the world’s land is cropland.• Clearing tropical rainforests and irrigating arid land- both of

which could have disastrous ecological consequences. Would reduce wildlife habitats, biodiversity & ecological integrity

• Nutrient poor soils cannot support crop growth for more than a few years

• Irrigation of arid land would require expensive dam projects, large inputs of fossil fuels to pump water long distances, depletion of groundwater supplies, expensive maintenance to prevent erosion, groundwater contamination, salinization and water logging

• Could accelerate global warming by increasing methane emissions due to the production of rice and cutting down trees.

Producing More Meat

Advantages of Feedlots

• Increased meat production

• Higher profits• Less land use• Reduced overgrazing• Reduced soil erosion• Help protect biodiversity

Disadvantages of Feedlots• Need large inputs of fossil

fuels, grain, fish meal, and water

• Concentrated animal wastes that can pollute water

• Antibiotics can increase bacterial resistance in humans

• Added Hormones can make humans sick

• Inhumane to the animals

Catching or raising more fish?

• Two thirds of fish from fisheries• One third from aquaculture (fish farming and ranching)• There has been a sevenfold increase in the number of

fish caught from 1950 to 1997. It has been declining ever since due to depleted fish stocks.

• 75% of the world’s major fisheries are fished above the sustainable yield.

• The fish industry is heavily subsidized by the government allowing overfishing

http://environment.nationalgeographic.com/environment/photos/oceans-overfishing.html#1305_600x450.jpg

Slide 32

Fig. 12.25, p. 285

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

Slide 33

Fig. 12.26, p. 286

Spotter airplane

Fish farmingin cage

Trawlerfishing

Purse-seinefishing

Sonartrawl flap

trawllines

trawlbag

Long line fishing

Lines withhooks

Drift-net fishing

Fish caughtby gills

float buoy

Slide 34

Fig. 12.27a, p. 287

100

80

60

40

20

01950 1960 1970 1980 1990

2000

Year

Total World Fish Catch

Cat

ch(m

illi

on

s o

f m

etri

c to

ns)

Slide 35

Fig. 12.27b, p. 287

25

20

15

10

5

01950 1960 1970 1980 1990 2000

Year

Total World Fish Catch

Per

cap

ita

cat

ch

(kil

og

ram

s p

er p

erso

n)

Slide 36

Fig. 12.28, p. 287

800

600

400

200

01960 1970 1980 1990 2000

Year

80

70

60

50

40

30

20

Har

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Abundance

Harvest

Slide 37

Fig. 12.29, p. 288

Human capture

Salmonprocessingplant

To hatchery

Eggs are taken from adultfemales and fertilized withsperm “milked” from males

Eggs and young arecared for in the hatchery

ModifiedLifeCycle

In the fall spawning salmondeposit eggs in gravel nests and die

Fry hatch in the spring...

And grow in the streamfor 1-2 years

Fingerlings migrate downstreamFingerlingsare released into river

Grow to smoltand enter the ocean...

NormalLifeCycle

Grow to maturityin Pacific Oceanin 1-2 years

Fish enter riversand head forspawning areas

Fish change form

Aquaculture: fish and shellfish raised for food.

• Aquaculture supplies 20% of the world’s commercial fish harvest.

• Aquaculture has increased 3.3 fold between 1984 and 1996, and is still increasing.

• Types of aquaculture• Fish farming – cultivating fish in a controlled

environment (pond or tank)• Fish ranching:holding anadromous species in

captivity for the first few years, releasing them and then harvesting the adults when they return to spawn. (carp, tilapia, milkfish, clams, oysters)

Slide 38

Fig. 12.30, p. 289

Advantages

Highly efficient

High yield in smallvolume of water

Increased yieldsthroughcrossbreedingand geneticengineering

Little use of fuel

Profit not tired toPrice of oil

Disvantages

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

Sustainable fishery management

• Owners should show that their harvests are sustainable before they can continue to operate.

• Monitor and enforce quotas for fisheries that are set below maximum sustainable yields.

• Establish and divide up fish quotas based on fairness, local needs and conditions.

• Reduce fishing subsidies to shrink the size of global fishing fleets, etc.

Government Food Policies

• Control prices: to keep consumers happy, but then farmers cannot make a living.

• Provide subsidies: $279 billion in 2004, if weather is good this causes a glut of food which depresses prices and puts farmers in developing countries out of business

• Market Forces: Eliminate subsidies, let the market decide prices and provide the poor with help buying the food.

Agricultural Policy, Food Aid and Land Reform

* Farming is a risky, difficult proposition. Weather, crop prices, crop pests and diseases, interest rates and the global market affect farming.

• Giving farmers subsidies to keep them in business increases food production, the problem is it leads to waste and over taxation and only corn, soy and wheat get big subsidies, things like broccoli do not. This makes vegetables expensive and corn products cheap.

• Eliminating price controls and subsidies would affect the poor and low middle class.

• Reward those farmers who protect soil, conserve water, reforest, protect and restore wetlands and conserve wildlife.