Feeding the World (Ch 11)

Human Nutritional Requirements are not always satisfied

Undernutrition

• 1 billion people do not have enough to eat
• 24,000 people starve to death each day… that is 8.8 million each year
• Undernutrition = people receive fewer calories than their minimum requirements
• An average person needs 2,200 kilocalories per day
• Undernutrition is due to economics, politics, conflict, and inefficiencies in distribution
• Most undernourished live in developing nations

Food insecurity in the Vegas Valley

​

Ave 12.8% in food insecure households

Overnutrition and Malnutrition

• Overnutrition = receiving too many calories each day
• Developed countries have abundant, cheap junk food, and people lead sedentary lives
• In the U.S., 25% of adults are obese
• Worldwide, over 400 million people are obese
• Malnutrition = a shortage of nutrients the body needs
• The diet lacks adequate vitamins and minerals
• Can lead to diseases

​

Malnutrition can lead to diseases�Developing Countries:

• Kwashiorkor = diet lacks protein and calories
• Occurs when children stop breast-feeding
• Bloated stomach, mental and physical disabilities
• Death if untreated

​

​

Malnutrition can lead to diseases�Developing Countries:

• Marasmus = inadequate calories from carbs, proteins, and lipids
• Wasting or shriveling of the body
• Death if untreated
• Goiter= diet lacks iodine
• A swollen neck and enlarged thyroid gland
• Eat foods higher in iodine like fish, seaweed, and fortified grains

​

​

Malnutrition can lead to diseases�Developed Countries

• Anemia = diet lacks iron Which means you don’t have adequate healthy blood cells to carry oxygen through the body.
• Tired & Weak Feelings
• Vitamin A Deficiency = diet lacks vitamin A
• Blindness in children
• Increased viral infections in adults
• Sweet potatoes, carrots, dark leafy vegetables contain vitamin A

​

​

Food Security

• Food security = guarantee of an adequate, safe, nutritious and reliable food supply.
• About 36 million Americans are “food insecure”
• Famine= food insecurity that is so severe that large # of people die.
• Why are some communities ‘food insecure”?
• Poverty – some people can’t afford it
• Political – refugees leave their food
• Crops go to feed livestock instead of people (40%)
• Crops go to make biofuels

​

Food Insecurity - Manufacturing biofuels affect food supplies

• Biofuels = are derived from organic materials
• Replace petroleum in engines
• Problem: Farmers sold corn for ethanol, not food. Could increase food costs
• Ethanol = a biofuel derived from corn
• Crops grown on land that could be used for the production of food

​

Environmental Problems Associated with Agriculture

Soil Erosion (Soil Conservation Strategies)

Deforestation

Fertilizer Runoff

Desertification

Soil Salinization

Waterlogging

​

​

​

​

​

Environmental Problem Associated with Agriculture

#1. Soil Erosion

• After plowing and harvesting, soil that is exposed to the elements are susceptible to being blown away by winds or washed away by water
• Even though soil is considered renewable, the rate of formation of new soil is slow and most soils that are under cultivation are currently being used unsustainably.

​

Environmental Problem Associated with Agriculture

#1. Soil Erosion

• Soil conservation strategies for reducing soil erosion:
• No-till agriculture
• Farming without plowing the land.
• Negatives: farmers must apply herbicides to land to control weed growth.
• Terracing
• Converting a hilly slope to flat terraces the follow the contours of the slope. (common in Asia to plant rice)
• Contour plowing
• Plowing across the slope of a hill rather than up and down the slope. (this prevents water for gaining down-hill momentum)
• Windbreaks
• A row of trees or shrubs that are planted next to or around fields to slow down the winds that could blow topsoil away.

​

Environmental Problem Associated with Agriculture

#2. Deforestation

• Deforestation is the removal of trees to clear land for agriculture.
• The removal of trees, reduces cover, which dries out soil.
• It increases soil erosion by eliminating the root infrastructure that held the soil in place
• It eliminates a carbon reservoir, which increases atmospheric carbon (as carbon dioxide)

​

Mitigation?

Environmental Problem Associated with Agriculture

#3. Desertification

​

• Desertification is the transformation of land once suitable for agriculture into a desert, typically by losing its bodies of water as well as vegetation and wildlife.
• Overgrazing is the major cause of desertification worldwide. (other causes include urbanization, climate change, and overdrafting of groundwater)

​

​

Mitigation?

​

Environmental Problem Associated with Agriculture

#4. Soil Salinization

​

• Soil salinization refers to the build up of salts in soil, which eventually will become toxic to plants ((3,000 – 6,000 ppm)
• Occurs when irrigation water accumulates and raises the water table to a level where it interferes with the growth of crops by submerging their roots.
• To mitigate… adequate drainage of irrigation water is needed.

​

Environmental Problem Associated with Agriculture

#5. Runoff

• Fertilizer runoff leads to eutrophication (algal blooms) and hypoxia (low dissolved oxygen) in waterways killing aquatic life.
• Pesticide runoff occurs when chemicals in pesticides dissolve in rain or irrigation water and enter waterways. Could lead to loss of biodiversity.

​

​

Mitigation?

Environmental Problem Associated with Agriculture

#6. Water logging

• Occurs when irrigation water accumulates and raises the water table to a level where it interferes with the growth of crops by submerging their roots.
• Plants need oxygen (air) in the soil to grow properly, which the water replaces.
• Also… a waterlogged area has little oxygen, which is the perfect environment for denitrifying bacteria to denitrify the soil. Recall that this results in LESS nitrates in the soil and, thus, less soil fertility.

​

Mitigation?

Ag FRQ

Describe TWO environmental issues associated with feeding the world then discuss how farmers can mitigate the issue.

The Green Revolution �(Industrial Farming Methods)

Energy Subsidy in Agriculture

Green Revolution

Negatives

Fertilizers

Irrigation

Pesticides/Herbicides

GMOs

​

Thomas Robert Malthus

Green Revolution = Ag innovations

• Mechanization and standardization applied to food production

Which environmental issues can you see in this picture?

Agricultural Revolutions

• 1st green revolution - 1950 to 1970 - industrialized agriculture
• 2nd green revolution - 1970 to 2000 - faster

growing, higher yielding crops

• 3rd green revolution - now - bioengeneering and GMOs (crops that are higher yielding, tastier, easier to transport, more drought resistant, and more pest resistant.)

Energy Subsidy - The energy spent per calorie of food produced.

In US, 10 calories spent to produce 1 calorie of food.

Where is most of the energy spent?

Most is due to fossil fuel use

• Fertilizers,pesticides
• Tractors, machinery
• Irrigation
• Transportation of food

Think like an APES student: What are the environmental consequences of this?

Federal Subsidies for Food Production

GR

• Mechanization
• Standardization of practices

• Fertilizers
• Irrigation
• Pesticides & herbicides
• GMOs

Bringing the innovations of the industrial revolution to agriculture

Results?

⬆️ Food Production

Feed more people

The Green Revolution - Negatives

The Green Revolution - Negatives

Green Revolution - Fertilizers

The growing of plants removes organic matter and nutrients from the soil and require limiting nutrients like nitrates and phosphates. Fertilizers help to replace these.

• Organic Fertilizers
• Composed of organic matter – decomposing plant & animal manure. Drawbacks??
• Synthetic Fertilizers
• Produced commercially. The nitrogen needed to make the nitrates comes from the combustion of N₂ gas to fix it into a plant-usuable form. This requires the use of fossil fuels. Other environmental issues?

​

​

Irrigation...

Pre GR…

Watering crops using surface water and aquifers. Little drainage strategies

Post GR…

Drip irrigation (saves water, reduces soil erosion, minimize weeds)

​

Increased use of irrigation canals and sprinkler systems

Ag FRQ II

• What is the energy subsidy in agriculture and why should APES students care about it?
• What are some of the results of the increased use of mechanization in agriculture?
• Describe TWO environmental consequences of the increased use of synthetic fertilizers in agriculture.

​

Herbicides & Pesticides & GMOs

Top 10 Crops

Top 10 Livestock

1. Corn
2. Wheat
3. Rice
4. Potatoes
5. Cassava
6. Soybeans
7. Sweet potatoes
8. Sorghum
9. Yams
10. Plantains

1. Fish
2. Chicken
3. Duck
4. Pigs
5. Rabbit
6. Turkey
7. Geese
8. Sheep
9. Goat
10. Cows

Implications? Most of our diet comes from a handful of cash crops.

Monocropping

Pluses… minuses… solutions?

Cover crop

Crop rotation

Solutions to monocropping

Monocropping leads to increased use of synthetic fertilizers, herbicides, and pesticides

​

Other potential solutions?

One could be GMOs

Golden Rice… increased Vitamin A in the rice. Solution for vitamin A deficiency?

GM crops are resistant to

• Most GM crops are herbicide and pesticide resistant

​

Bt Crops

Round-Up Crops (Glyphosate weed killer)

GM crops are bioengineered to be resistant to Roundup, a broad-spectrum weed killer.

​

Implications?

Problems with Herbicides & Pesticides

Pests and weeds evolve resistance to pesticides and herbicides

• Some individuals are genetically immune to the pesticides. They pass these genes on their offspring.

​

​

​

​

​

Organic Farming

Are these the answers to Pesticide use?

Integrated Pest Management – A method to reduce pesticide use

• IPM uses a variety of techniques.
• Crop Rotation (prevents pest infestations)
• Intercropping (prevents specialized pests from succeeding)
• Use of Pesticide Resistant Seed Varieties
• Use of natural predators to control the pests (Biological control)
• Uses pesticides sparingly

​

Biotechnology is impacting our lives

• Biotechnology = the application of biological science to create products derived from organisms
• Transgenic organism = an organism that contains DNA from another species
• Transgenes = the genes that have moved between organisms
• Biotechnology has created medicines, cleaned up pollution, and dissolved blood clots

Golden Rice (Vitamin A) & Grapple (apple that tastes like a grape)

• The production of crops without the use of synthetic pesticides or fertilizers.
• Organic Food Production Act (1990) establishes national standards for organic products
• The USDA issued criteria in 2000 by which food could be labeled organic
• Food must be grown on soils which has been free of banned substances for 3 years
• Some states pass even stricter guidelines for labeling
• California, Washington, Texas
• Nearly 500 organizations offer certification services

Organic Agriculture

The Pros and Cons of Organic Farming

PROS:

• Farmers have lower input costs, enhanced income, reduced chemical pollution, and soil degradation
• They practice stewardship to the land
• Obstacles include risks and costs of switching to new methods
• Consumers are concerned about pesticide’s health risks
• They want to improve environmental quality
• Obstacles include the higher price of organics

CONS:

• Farmers do experience some environmental consequences
• They till and plow their lands.
• Some pest control methods may include propane or other fossil fuels.

​

Organic agriculture is booming

• Organic farmers can’t keep up with demand
• U.S. consumers spend $22.9 billion/year
• Production is increasing
• 1.8 million ha in the U.S.

Governments can support organic farming

• In 1993, the European Union adopted a policy supporting farmers financially during conversion to organic farming.
• Originally, the U.S. offers no support so organic production was low
• Now things are better…
• The 2008 Farm Bill gives $112 million over 5 years for organic agriculture
• Many farmers still can’t switch, because they can’t afford the temporary loss of income
• In the long run, organic farming is more profitable than conventional farming

Modern Agribusiness includes the farming of meat and fish

Feed-Lot Agriculture

Harvesting Fish & Shellfish

Aquaculture

Feedlot Agriculture

• Also called: Concentrated Animal Feeding Operations (CAFOs)
• The primary goal is to grow animals faster & more economically by:
• Using grains grown on crop lands
• Using antibiotics & nutrient supplements
• While minimizing land costs & using manure to fertilize the land

​

• Over half of the world’s pork and most of its poultry are grown in CAFOs

​

​

​

*Beef Cattle, Dairy Cows, Hogs & Poultry

Feedlot Agriculture Pollutes Water and Air

• Feedlots produce huge amounts of manure and urine
• Causing eutrophication
• Waterborne pathogens sicken people
• Crowded, dirty housing causes outbreaks in disease
• Heavy use of antibiotics, hormones, heavy metals
• Chemicals are transferred to people
• Microbes evolve resistance to antibiotics
• Diseases: Mad Cow, Avian Flu, H1N1, E.Coli
• Air pollution: odors, ammonia (acid rain), methane
• More greenhouse gases (CO₂, methane, nitrous oxides) than automobile emissions

Environmental ramifications of eating meat

• When we choose what to eat, we choose how we use our earth’s resources.
• Land and water are needed to raise food for livestock
• Producing eggs and chicken meat requires the least space and water
• Producing beef requires the most space and water.

Harvesting Fish & Shellfish

• A variety of techniques are used to harvest wild marine species.
• Long-Line Fishing
• Up to 80 miles of fishing line is strung out in the water with thousands of baited hooks attached to it.
• Purse Seine Fishing
• A net is used to surround a large school of fish such as tuna, herring or mackerel.

​

Harvesting Fish & Shellfish

• Drift-Net Fishing
• A net is set to hang in the water from the surface to 50 feet below, extend over 40 miles and drug to catch fish

​

• Trawler Fishing
• Large metal chain baskets holding nets are dragged across the ocean floor scouring the bottom for shrimp, scallops and flounder. They scrape up just about everything on the ocean floor.

​

​

​

Harvesting Fish & Shellfish

• Fishery Collapse - World’s fish populations are plummeting … decline of fish populations by 90%… WHY?
• Increased Demand
• The human population is growing
• Better Technology
• Ships now have advanced technology & improved fishing gear: satellites, sonar and refrigerated ships.
• Bycatch
• N0n-targeted species can be caught and killed.
• Environmental damage
• Corals and plants are killed or damaged from the fishing techniques… so the food chain is disrupted

​

Harvesting Fish & Shellfish - Laws

• Fishery Conservation & Management Act of 1976 –
• Later renamed the Sustainable Fisheries Act 1996
• Conservation is stressed
• Species Sustainability is stressed
• Whaling has subsided dramatically and some populations have begun to recover
• Protection of marine habitats stressed – in some cases… no fishing was allowed until populations recover.
• Internationally: Australia has the largest protect marine sanctuaries and parks… protecting turtles, sea lions, dolphins, etc.

​

​

Aquaculture

Is aquaculture the answer to fishery collapse?

• Aquaculture = raising aquatic organisms in a controlled environment
• Species are raised in open-water pens or land-based ponds
• It is the faster-growing type of food production:
• Provides ¾ of the world’s fish & ½ of the shellfish
• Over 220 freshwater and marine species are grown
• China does it best!
• Largest indoor aquaculture farm is in Virginia (talapia)

​

Aquaculture - benefits and drawbacks

• Benefits:
• A reliable protein source
• Can be sustainable
• Reduces pressure on overharvested wild fish
• Energy efficient

• Drawbacks:
• Diseases require expensive antibiotics
• Lots of waste
• Uses grain
• Escaped GM fish introduce disease or outcompete wild fish

Sustainable Agriculture

Our ultimate goal!

Sustainable Agriculture

• Sustainable Agriculture is our ultimate goal!
• Adequate amount of food is produced.
• Soil quality is enhanced.
• Use of nonrenewable resources is minimized.
• Provides adequate moneys for farmers.
• Practices the support sustainable agriculture:
• Intercropping (two crops in the same field)
• Crop rotation (peas - year 1, corn - year 2)
• Agroforestry (planting trees with vegetables)
• Contour Plowing (helps to conserve soil and prevent erosion)

​

Sustainable Agriculture uses Locals Farmers

• Sustainable agriculture reduces fossil fuel use from long-distance transport of products
• Food is chemically treated for freshness and color
• Farmers’ markets = provide fresh, locally grown food
• Community-supported agriculture (CSA)
• Consumers pay farmers �in advance
• Consumers get fresh food
• Farmers get a guaranteed �income

Sustainable Agriculture mimics natural ecosystems

• Ecosystems operate in cycles
• Stabilized by negative feedback loops

​

• Example: Small-scale Japanese farmers add ducks to rice fields
• Ducks eat weeds, insects, snails
• Their waste is fertilizer
• Their paddling oxygenates �the water
• Fish and ferns provide food �and habitat

Sustainable Agriculture Preserves Crop Diversity

• Preserving native variants protects against crop failure
• Monocultures are vulnerable
• Wild relatives contain genes that can provide resistance to disease and pests
• But Mexico has lifted its ban on transgenic corn
• We have lost a great deal of genetic diversity in crops
• U.S. crops have decreased 90% in diversity
• Market forces discourage diversity in food’s appearance
• Food producers prefer uniform, standardized food
• Seed banks = institutions that preserve seed types as living museums of genetic diversity
• Seeds are collected, stored, and periodically planted
• The “doomsday seed vault” in Norway stores millions of seeds from around the world

​

​

• Not all insects are pests; some are absolutely vital
• 800 crop species rely on insect pollinators
• Pollination = male plant sex cells fertilize female sex cells
• By wind or animals
• Pollinators include:
• Hummingbirds
• Bats
• Insects (bees, wasps, etc.)
• Reducing or eliminating pesticide use and planting flowering plants will help preserve bees

​

Flowers are evolutionary adaptations to attract pollinators

​

Bees pollinate over 100 crops and contribute $15 billion in services/year

​

​

Sustainable Agriculture stresses the Conservation of Pollinators

Sustainable Agriculture will help us to

FEED THE WORLD!