4/18/13

No Article Review this week

Energy plan due next Friday

Homework: Read 11.4 and 11.5

Reading Quiz

Tomorrow we will have a quiz over tonight’s reading. Be able to do the following

Explain soil degradation, slash and burn agriculture, and desertification.

Describe the benefits and drawbacks of sustainable farming practices, no-till agriculture, and integrated pest management.

Discuss organic agriculture.

Understand CAFOs, impacts of fish harvesting, and aquaculture

Review

Compare and contrast the various forms of malnutrition.

Discuss factors that contribute to malnutrition.

Relate the concept of energy subsidy to the concept of ecological footprint.

Describe the Green Revolution.

Objectives

Discuss the benefits and drawbacks of industrial farming practices.

Debate using genetically modified organisms in agriculture.

Questions

How has farming changed in the last 75 years?

Do The Math

Before we get into it, work through this math problem.

Help those at your table.

Don’t give answers, give help

Do The Math

On farms in the midwestern United States, a hectare of land yields roughly 370 bushels of corn (equivalent to 150 bushels per acre). A bushel of consists of 1,250 ears of corn, and each ear typically contains 80 kilocalories. Assume that a person eats only corn and requires 2,000 kilocalories per day.

How many calories does a person require in a year?

2,000 kilocalories/day X 365 days/year = 730,000 kilocalories.year

Do The Math

On farms in the midwestern United States, a hectare of land yields roughly 370 bushels of corn (equivalent to 150 bushels per acre). A bushel of consists of 1,250 ears of corn, and each ear typically contains 80 kilocalories. Assume that a person eats only corn and requires 2,000 kilocalories per day.

How many calories does a hectare of corn produce?

370 bushels/hectare X 1250 ears/bushel X 80 kilocalories/ear = 37,000,000 kilocalories/hectare

Do The Math

If a person were to eat only corn, how many hectares of land would it take to support the person?

730,000 kilocalories/year ÷ 37,000,000 kilocalories/hectare = .02 hectares of land

Do The Math

What if the person ate only beef? 20 kg of grain are needed to produce 1 kg of beef. So it would take 20 times as much land to feed a person who only at beef. How much land would it take to support that person?

0.02 X 20 = 0.4 hectares

Do The Math

If the Earth has about 1.5 billion hectares of land suitable for growing food, is there sufficient land on Earth to feed all the inhabitants of the planet if they only ate beef?

7 billion people X 0.4 ha/person = 2.8 billion ha needed

Do The Math

How many people eating a beef-only diet could Earth support?

1.5 billion ha land X (1 person/0.4 ha) = 3.75 billion people

Green Revolution

What are the major components of the Green Revolution?

Mechanization

Irrigation

Fertilization

Monocropping

Pesticides

Mechanization

How do labor costs drive the use of mechanization?

What is an economy of scale?

With regard to farm size and crop diversity, what are the consequences of mechanization?

Irrigation

What are the benefits of irrigation?

What are the consequences?

Aquifer damage

Waterlogging

Salinization

Fertilizers

Why does industrial agriculture make fertilizer use necessary?

What are the primary nutrients in fertilizer?

What are the two categories of fertilizer?

Fertilizers

How are synthetic fertilizers produced?

What are their benefits and drawbacks?

What are the benefits and drawbacks of organic fertilizers

Monocropping

What is monocropping?

What are the benefits and drawbacks of monocropping?

Pesticides

How does monocropping make pesticide use more prevalent?

What is the difference between insecticide and herbicide?

Selective and broad-spectrum?

What are the benefits and drawbacks?

Pesticides

Talk to me about DDT and bioaccumulation?

What is pesticide persistence?

How does pesticide use lead to resistance?

What is the pesticide treadmill?

GMO

Take 5 minutes and discuss GMO with your table

What do you know?

Are you in favor?

What questions do you have?

Have someone take notes to report to class

GMO

How does a genetically modified organism come to be?

What are the benefits?

Crop yield

Changes in pesticides

Increased profit

GMO

What are the drawbacks?

Safety concerns

Effects on Biodiversity

Regulation

AP Practice

Which of the following describes a fundamental characteristic of the Green Revolution in food resources?

A. The application of higher levels of organic fertilizers to increase rice production

B. Deforestation to provide field crops with increased sunlight for photosynthesis

C. The addition of calorie, fat, and fiber percentages to the information provided on food package labels

D. The development of new strains of crops with higher yields

E. The discovery that chlorophyll adds nutritional value to wheat, rice, and sorghum