Chapter 11: Feeding the World

Chapter 11: Feeding the World

Nutrition

• Food Security

• Macro vs. micro nutrients

• Malnutrition

• Undernutrition

• Overnutrition – WHO | Obesity and overweight

• Malnutrition and Gender Inequality

Protein Energy Malnutrition

• Marasmus

• Kwashiorkor

Ways to reduce childhood deaths from hunger and malnutrition

• Immunize

• Breastfeed

• Prevent dehydration

• Provide family planning

• Increase education for women

• Provide Vitamin A

Famine

• Sudan, Africa: Civil war since 1983

• Mother describes life in Southern Sudan

• Teaching Farming Techniques

Animation: Land Use

PLAYANIMATION

Green Revolution • Increased yields per unit area since 1940’s

Three steps: – Developing and planting monocultures,

selective breeding or genetically engineered crops

– Increased use of fertilizers, pesticides and water

– Increasing the intensity and frequency of cropping

– The Green Revolution: Waging A War Against Hunger

Agriculture

• Where would you find the following types of agriculture and what types of crops are grown by each? – Traditional (low input)– Industrial (high input)– Plantation

Fig. 13-4, p. 275

Plantation agriculture

Shifting cultivation

Industrialized agriculture

No agriculture

Intensive traditional ag.

Nomadic herding

Traditional subsistence agriculture

Traditional intensive agriculture

Industrial agriculture (high input)

•What are the high inputs required to make industrialized agriculture work?

•Tend to be monocultures

Plantation agriculture• Type of industrialized agriculture• Problems associated with plantation agriculture

Tea plantation in MalaysiaCoffee plantation Kenya

Organic Farming

• Food grown without the use of synthetic pesticides and fertilizers

• Disadvantages of organic farming?

Three ways to decrease hunger, malnutrition and the harmful environmental effects of agriculture:

– Slow population growth.– Sharply reduce poverty.– Develop and phase in systems of more

sustainable, low input agriculture over the next few decades.

Figure 13-34Figure 13-34

Back to the Start

Ungrazed Grazed Recovery

Metabolicreserve

Metabolicreserve

Metabolicreserveintact

Grazing

Ungrazed Overgrazed Death

Metabolicreserve

Death

Most ofmetabolicreserveeaten

Overgrazing

Producing More Meat• Rangelands vs. feedlots (Concentrated Animal

Feeding Operations - CAFO’s)

The Meatrix Meatrix 2 Meatrix 2.5 Grocery Store Wars

Fig. 13-21, p. 289

Trade-Offs

Animal Feedlots

Advantages Disadvantages

Increased meat production

Need large inputs of grain, fish meal, water, and fossil fuelsHigher profits

Concentrate animal wastes that can pollute water

Less land use

Reduced overgrazing

Reduced soil erosion

Antibiotics can increase genetic resistance to microbes in humans

Help protect biodiversity

Hogs & Water Quality

Image of Hog Farms

Efficient or inefficient?

Use of antibiotics and steroids in meat production

Animal Antibiotic Overuse Hurting Humans? - CBS Evening News - CBS News

Growth steroids (hormones): cattle and sheep

Milk Production hormones: dairy cattle (not beef cattle)

No growth hormones allowed for poultry (turkey, chicken and ducks) or pigs

Fish farming in cage

Trawler fishing Spotter airplane

Sonar

Trawl flap Trawl

lines

Purse-seine fishing

Trawl bagFish school

Drift-net fishingLong line fishing

Lines with hooks

Fish caught by gills

Deep sea aquaculture cage

Float

Buoy

Fishing Methods

Turtle excluder device

Fig. 13-24, p. 292

Trade-Offs

Aquaculture

Advantages Disadvantages

High efficiency Needs large inputs of land, feed, and waterHigh yield in

small volume of water

Large waste output

Destroys mangrove forests and estuaries

Can reduce overharvesting of conventional fisheries Uses grain to feed

some species

Low fuel useDense populations vulnerable to disease

Tanks too contaminated to use after about 5 years

High profits

Profits not tied to price of oil

Dan Barber Video

Fig. 13-25, p. 293

Solutions

More Sustainable Aquaculture

• Use less fishmeal feed to reduce depletion of other fish

• Improve management of aquaculture wastes

• Reduce escape of aquaculture species into the wild

• Restrict location of fish farms to reduce loss of mangrove forests and estuaries

• Farm some aquaculture species in deeply submerged cages to protect them from wave action and predators and allow dilution of wastes into the ocean

• Certify sustainable forms of aquaculture

Government Policies and Food Production

• Governments use three main approaches to influence food production:– Control prices to keep prices artificially low.– Provide subsidies to keep farmers in

business.– Let the marketplace decide rather that

implementing price controls.

What is a subsidy? • Financial assistance from the government to

assist a business• Agricultural subsidies:

– Direct payments to farmers for certain levels of output– Price supports that keep prices higher to increase

revenue for farmers: Ex: the government sets a minimum price for sugar that it guarantees to sugar growers. If the market price drops below that level, the government makes up the difference.

– Protection against imports of certain products (sugar, dairy) to keep market for local producers

Animation: Pesticide Examples

PLAYANIMATION

Persistence

Resistance

THE GENE REVOLUTION• To increase crop yields, we can mix the genes

of similar types of organisms and mix the genes of different organisms.– Artificial selection has been used for centuries to

develop genetically improved varieties of crops.– Genetic engineering develops improved strains at

an exponential pace compared to artificial selection.

• Controversy has arisen over the use of genetically modified food (GMF).

Mixing Genes• Genetic

engineering involves splicing a gene from one species and transplanting the DNA into another species.

Figure 13-19Figure 13-19

PBS - harvest of fear: what about this fish?

Proposition 37 in CA

How Would You Vote?

• Do the advantages of genetically engineered foods outweigh their disadvantages?– a. No. The impact of these foods could cause

serious harm to the environment or human health.

– b. Yes. These foods are needed to combat world hunger.

Solutions: Making the Transition to More Sustainable Agriculture

• More research, demonstration projects, government subsidies, and training can promote more sustainable organic agriculture.

Figure 13-35Figure 13-35