Food and Agriculture

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Food and Agriculture

• Environmental Science

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10,000 Years ago or so.
And two hundred years ago
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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
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Feeding the World

• You 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?

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Feeding the World

• You 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

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Famine

• In 1985 crops failed in Ethiopia, causing
• famine.

• WRITE DOWN YOUR THOUGHTS BE READY TO DISCUSS!
• What is the
• definition of famine?

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Famine

• The widespread malnutrition and starvation in an
  area
• due to a shortage of food, usually caused by a
• catastrophic event.

• WRITE DOWN YOUR THOUGHTS BE READY TO DISCUSS!
• What does malnutrition
• mean?
• What does starvation mean?
• What does nutrition mean?

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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.

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Humans and Nutrition

• Malnutrition 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 bodys needs.

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Forms of Malnutrition

• Amino acid deficiency
• Insufficient variety of food
• Low Calorie consumption

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Malnutrition can lead to Starvation

• Starvation is the most
• extreme form of
• malnutrition.
• Prolonged starvation can
• result in organ failure and
• eventual death.

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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.

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Nutrition around the World

• In 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.

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Diets around the World

• People 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.

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Lets 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 category
• State reasons for your choices

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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
• Lets hear more

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Feeding the World

• WRITE DOWN YOUR
• THOUGHTS, 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?

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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.

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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
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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!

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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

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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!

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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

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The World Food Conundrum

• The worlds 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!

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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

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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 Worlds grain production has not
increased as much as the human population.
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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.

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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

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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!
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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.

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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

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The Green Revolution Benefits

• -Increased Yields
• -Labor Saving
• -Saved 1 billion lives

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Crops and Soil
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Agriculture

• Much of the Earths 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!
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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.

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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.

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And Farms grew larger and more Productive.
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Changing the landscape of Ag
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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.

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The Green Revolution Downsides

• Are 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 GMOs 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?

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Modern World

• Developed World Factory farming dominates,
  subsidized agriculture.
• Developing World Green revolution spreading or
  adopted, displaced farmers, low-cost agriculture.
• Second Green Revolution GMOs, cont. spread

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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

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Soil Layers and Composition
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Land Degradation

• Loss of land productivity resulting from soil
  erosion, insufficient irrigation, deforestation,
  overpopulation, desertification and drought.

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Soil Erosion A Global Problem

• The process in which the materials of the Earths
  surface
• are loosened and carried by wind, water, ice, or
  gravity

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Lab ActivityPreventing 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

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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.

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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.

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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.

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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 1930s

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Soil Conservation
There are ways to protect and manage topsoil to
prevent erosion

• Soil retaining terraces on hills

Contour plowing
Both of these methods keep water from running
directly downhill, preventing erosion.
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Soil Conservation (Cont)
More ways to protect and manage topsoil to
prevent erosion

• 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

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Soil Conservation (Cont)
More ways to protect and manage topsoil

• Enrich the Soil
• Organic matter
• Compost- partly decomposed organic matter
• Inorganic matter
• Fertilizers
• N, P, K

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Soil Conservation (Cont)
More ways to protect and manage topsoil

• 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

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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
worlds potential food harvest
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Pest Control

• Pesticide a poison used to destroy pests
• Examples include insecticides, rodenticides, and
  herbicides

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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.

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Other Concerns about Pesticide Usage

• Human Heath Concerns
• Increased rates of cancers
• Nervous System disorders
• Application requires safety precautions and in
  industry, mandatory training
• Environmnetal Concerns
• Pollution
• Persistence ? accumulation

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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

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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.

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Engineering a Better Crop

• Scientists use genetic engineering to transfer
  desirable traits, such as resistance to certain
  pests, from one organism to another