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Food and Agriculture

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Title: Food and Agriculture


1
Food and Agriculture
  • Environmental Science

2
10,000 Years ago or so.
And two hundred years ago
3
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
4
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?

5
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

6
Famine
  • In 1985 crops failed in Ethiopia, causing
  • famine.
  • WRITE DOWN YOUR THOUGHTS BE READY TO DISCUSS!
  • What is the
  • definition of famine?

7
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?

8
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.

9
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10
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.

11
Forms of Malnutrition
  • Amino acid deficiency
  • Insufficient variety of food
  • Low Calorie consumption

12
Malnutrition can lead to Starvation
  • Starvation is the most
  • extreme form of
  • malnutrition.
  • Prolonged starvation can
  • result in organ failure and
  • eventual death.

13
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.

14
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.

15
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.

16
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

17
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

18
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?

19
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.

20
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
21
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!

22
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

23
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!

24
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

25
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!

26
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

27
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.
28
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.

29
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

30
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!
31
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.

32
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

33
The Green Revolution Benefits
  • -Increased Yields
  • -Labor Saving
  • -Saved 1 billion lives

34
Crops and Soil
35
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!
36
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.

37
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.

38
And Farms grew larger and more Productive.
39
Changing the landscape of Ag
40
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.

41
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?

42
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

43
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

44
Soil Layers and Composition
45
Land Degradation
  • Loss of land productivity resulting from soil
    erosion, insufficient irrigation, deforestation,
    overpopulation, desertification and drought.

46
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

47
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

48
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.

49
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.

50
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.

51
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

52
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.
53
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

54
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

55
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

56
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
57
Pest Control
  • Pesticide a poison used to destroy pests
  • Examples include insecticides, rodenticides, and
    herbicides

58
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.

59
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

60
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

61
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.

62
Engineering a Better Crop
  • Scientists use genetic engineering to transfer
    desirable traits, such as resistance to certain
    pests, from one organism to another
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