Food and Agriculture

Environmental Science

10,000 Years ago or so….

And two hundred years ago…

Earlier this century… Farming was labor-intensive Crop productivity was low

Legumes (N fixation) Grains (Rice, Wheat, Corn) Crop rotation Organic fertilizers

(N, P, K-manure, guano)

Animals were used to do farm labor

www.campsilos.org/mod2/ teachers/r1_part5.shtml

Feeding the WorldYou are the owner of this farmland in rural

Pennsylvania.

WRITE DOWN YOUR THOUGHTS, & BE READY TO DISCUSS!

What might your daily life involve? What concerns and needs

would you have to maintain your income and way of life?

Feeding the WorldYou are the owner of this farmland in rural Pennsylvania.

What might your daily life involve?

Early wake up, long hours, hard labor, etc…

What concerns and needs would you have to maintain your income and way of life?Increased costs of farming, inability to provide for your

family, industrialization in agriculture,

etc…

Famine

In 1985 crops failed in Ethiopia, causing famine.

WRITE DOWN YOUR THOUGHTS & BE READY TO DISCUSS!

What is the definition of famine?

FamineThe widespread malnutrition and starvation in an

area due to a shortage of food, usually caused by acatastrophic event.WRITE DOWN YOUR THOUGHTS & BE READY TO DISCUSS!

What does malnutrition mean?What does starvation mean?What does nutrition mean?

Humans and Nutrition The amount of energy that is available in food is

expressed in Calories. The human body uses food as a source of energy and to

build and maintain body tissues. The major nutrients we get from food are carbohydrates,

proteins, and lipids. Our bodies need smaller amounts of vitamins and

minerals to remain healthy.

Humans and NutritionMalnutrition is a disorder of nutrition that results when a person does not consume enough of each of the nutrients that are needed by the human body OR is a condition that occurs when people do not eat enough of a variety

of foods to fulfill all of the body’s needs.

Forms of Malnutrition

Amino acid deficiency Insufficient variety of food Low Calorie consumption

Malnutrition can lead to Starvation

Starvation is the most extreme form of malnutrition.

Prolonged starvation can result in organ failure and

eventual death.

What is Nutrition? Where does it come from?

Nutrition refers to the sum of the building blocks of life that build and maintain body tissues, support growth, and provide energy. Nutrition comes from your diet – the type and amount of food that you eat.

WRITE DOWN YOUR THOUGHTS & BE READY TO DISCUSS!

Do you think nutrition and diet differ depending upon where you live? Explain and provide examples.

Nutrition around the WorldIn most parts of the world people eat larger amounts of foods high in carbs, such as rice, corn, potatoes, and bread as shown below. Grains are the food produced in the greatest amounts worldwide.

Diets around the WorldPeople worldwide generally consume the same major nutrients and kinds of foods, but diets vary by

region.People in more developed countries tend to eat more food and larger proportions of proteins and fats.

Let’s Think About Food!Answer the following in your journals:

What is food?How does a culture decide what to eat?

Then, Make a table of foods divided into the following categories:

“Prefer to eat” “Might eat if I had to” “Would never eat”

Include at least 8-10 foods in each categoryState reasons for your choices

Probably On My “Will Never Eat” List: Huitlacoche or Cuitlacoche

Corn fungus (smut) Ustilago maydis

Delicacy with a smoky taste

Can be cooked with garlic and chilies or used fresh in soups, stews, or salsas

Let’s hear more…

Feeding the WorldWRITE DOWN YOURTHOUGHTS, & BE READY TO DISCUSS!

Do you think there is enough food available in the world to feed everyone?

If yes, why are there people starving in some areas of the world?

If no, how many people do you think there are in the world who are undernourished?

Feeding the World

As the human population grows, farmland and suburbs replace forests and grasslands. Feeding everyone while maintaining natural ecosystems becomes

more difficult.

Different kinds of agriculture have different environmental impacts and different levels of efficiency.

Food Efficiency

Efficiency- the measure of the quantity of food produced on a given area of land with limited inputs and resources.

So, an ideal food crop is one that efficiently produces a large amount of food with limited negative impact on the environment

THINK!Food Efficiency

Scientists are looking into ways to improve the efficiency of food production.

How might this be achieved?

WRITE DOWN YOUR THOUGHTS & BE READY TO

DISCUSS!

THINK!Food Efficiency

The goal is to have high yields! Yield is the amount of food produced in

given area. Organisms that can survive and thrive in a

variety of climates. Organisms that do not require large amounts

of fertilizer, pesticides, or fresh water. Newly discovered organisms

GLASSWORTAKA: Pickle Weed or Sea Pickles Herb w/salty taste

Eaten pickled or in fresh salads

Found in salt marshes and beach dunes on the East and west Coasts of the US

Low growing, Fleshy like succulents (cacti)

Scrunches like broken glass when stepped upon

HIGHLY SALT TOLERANT!

Alternative Food Sources: Fungus for Dinner Anyone? British Company

Developed a food product from fungus Fusarium venenatum

Grown in fermentation vats, like yogurt

Mixed with eggs and flavorings

Turned into imitation beef or chicken product Quorn TM

The World Food Conundrum The world’s farmers produce enough grain to feed up to 10 billion people an adequate vegetarian diet.

THINK! Why then does malnutrition exist?

WRITE DOWN YOUR THOUGHTS & BE READY TO DISCUSS!

The Poverty Trap Most malnutrition stems from poverty! Farm workers and subsistence farmers- those

who grow food for themselves and local use- suffer most.

Reside in Africa, Asia, and the Mts. of South America

More Income/More Food The number of people living in poverty has decreased by a half a billion since 1980 due primarily to rapid economic development in China and India.

However, the World’s grain production has not increased as much as the human population.

The Green Revolution

Between 1950 and 1970, worldwide increases in crop yields without using more land

Called “The Green Revolution”

Resulted from using new varieties of grain that needed more water and chemicals.

After WWII, the Green Revolution

Development of new crop hybrids Spread of MODERN methods of ag:

Chemical fertilizers Efficient irrigation Use of heavy machinery Pesticides, herbicides, fungicides

THINK!The Green Revolution

What do you think were direct results of the green revolution in terms of human consumption, health, and livelihood?

How was it beneficial? Were there limitations?

WRITE DOWN YOUR THOUGHTS & BE READY TO DISCUSS!

THINK!The Green Revolution

The Green Revolution reduced price of food

& improved the lives of millions of people However, it did not really

help subsistence farmers, who could not afford the machinery, water, or chemicals that the new varieties required.

The Green Revolution As a result of the overuse of

fertilizers and pesticides, yields from green revolution crops are falling

Chemicals required by new crop varieties can degrade the soil if they are not used properly

Research today, is devoted to high yield, nutritious crops that can be grown on poor soil, with less water & chemicals

The Green Revolution: Benefits

-Increased Yields

-Labor Saving

-Saved 1 billion lives

Crops and Soil

Agriculture

Much of the Earth’s surface cannot be farmed. Only about 10% is arable land.

THINK! What do you think arable land is?

WRITE DOWN YOUR THOUGHTS & BE READY TO DISCUSS!

Agriculture

Arable land is farmland that can be used to grow crops.

As the human population continues to grow, the amount of arable land per person decreases.

Traditional Agriculture Plows pushed by the farmers or pulled by livestock. Harvesting by hand. Organic fertilizers, such as manure, are used to

enrich soil. Fields are irrigated by water flowing through ditches. Used since the earliest days of farming, centuries

before tractors and pesticides were invented.

And Farms grew larger and more Productive….

Changing the landscape of Ag

Modern Agriculture Machinery powered by fossil

fuels plow the soil and harvest crops.

Synthetic chemical fertilizers have replaced manure and plant wastes to fertilize soil.

Synthetic chemicals for pest control.

A variety of overhead sprinklers

and drip systems may be used for irrigation.

The Green Revolution: DownsidesAre there any? Why is organic food so expensive? What are the social downsides of the green

revolution? What fixes are there? What are the downsides of the Green

Revolution? What fixes are there? Are GMO’s really safe for you: should they be

labeled? Are “Frankenfoods” safe for the environment? Should factory farming be regulated for

pollution and animal health reasons?

Modern World

Developed World: Factory farming dominates, subsidized agriculture.

Developing World: Green revolution spreading or adopted, displaced farmers, low-cost agriculture.

Second Green Revolution: GMO’s, cont. spread

Fertile Soil: The Living Earth Review the “Soil Identification Lab”

Know all key terms Know layers & composition of soil (next slide) Know key organisms found in soil & their roles

in maintaining fertile soil. Know how to determine % composition of soil

parts Know how to read the “soil triangle” and

“flowchart” given data to determine soil type Review questions from the lab & Be able to

answer related questions

Soil Layers and Composition

Land Degradation Loss of land productivity resulting from soil erosion,

insufficient irrigation, deforestation, overpopulation, desertification and drought.

Soil Erosion: A Global ProblemThe process in which the materials of the Earth’s surface

are loosened and carried by wind, water, ice, or gravity

Lab Activity:Preventing Soil Erosion Objectives:Students will work in groups of 3-4 to examine three different soil types to determine which soil type has the most/least erosion and water runoff.

Procedure: Construct land models Perform the experiments Analyze & explain the results

Desertification The process by which human activities (or climatic

changes) make arid or semiarid areas more desert-like When crops planted too frequently and time between

plantings is shortened The term “fallow” means unplanted.

Desertification can lead to poverty and famine.

Drought Drought is a prolonged period during

which rainfall is below average, and crops grown without irrigation may produce low yields or fail entirely.

Drought is more likely to cause famine in places where food is grown locally.

Sahel Region of Africa One of the poorest and most environmentally

damaged places on Earth. In the 1970s drought and famine killed nearly

200,000 people. Vicious cycle of soil erosion, insufficient

irrigation, deforestation, overpopulation, desertification and drought.

With land degradation, the scramble for income has intensified.

Instead of sticking to the land, rural workers are now heading for the cities overcrowding.

Open sewers are common in the cities, and electricity, running water and trash collection all too infrequent.

The Dust Bowl One of the worst

man-made ecological disasters in American history.

Wheat boom of the “Great Plow-Up”

Decade long drought of the 1930’s

Soil Conservation

Soil retaining terraces on hills

There are ways to protect and manage topsoil to prevent erosion

Contour plowing

Both of these methods keep water from running directly downhill, preventing erosion.

Soil Conservation (Cont)

No-till farming Crop harvesting without

turning the soil over, as in traditional farming

The seeds of the next crop are planted among the remains of the previous crop.

Although this method saves time and reduces soil erosion, it is not suited for all crops

More ways to protect and manage topsoil to prevent erosion

Soil Conservation (Cont)

Enrich the Soil Organic matter

Compost- partly decomposed organic matter

Inorganic matter Fertilizers N, P, K

More ways to protect and manage topsoil

Soil Conservation (Cont)

Irrigation Canals to prevent salinization- the accumulation of salts in the soil Prevalent in low rain

areas Naturally salty soils to

start Irrigated land after water

evaporates

More ways to protect and manage topsoil

High Yields Require Pest Control

A pest is any organism that occurs where it is not wanted or that occurs in large enough numbers to cause economic damage Insects Rodents Weeds Fungi Microorganisms

Worldwide, pests destroy about one-third of the world’s potential food harvest

Pest Control Pesticide – a poison used to destroy pests Examples include insecticides,

rodenticides, and herbicides

Pest Control

Over time, spraying large amounts of pesticide to get rid of pests usually makes the pest problem worse.

Pest populations may evolve resistance, the ability to survive exposure to a particular pesticide.

Other Concerns about Pesticide Usage

Human Heath Concerns:Increased rates of cancersNervous System disordersApplication requires safety precautions and in industry, mandatory training

Environmnetal Concerns:PollutionPersistence accumulation

Pest Control Biological pest control is the use of certain

organisms by humans to eliminate or control pests Biological pest control aims to:

• maintain tolerable pest levels

• elevate plant defenses

• leave non-species unharmed

• disrupt insect breeding

Integrated Pest Management The goal of integrated pest management

is not to eliminate pest populations but to reduce pest damage to a level that causes minimal economic damage.

Engineering a Better Crop Scientists use genetic engineering to transfer desirable traits, such as resistance to certain pests, from one organism to another