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Food Resources Feeding the World.

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Presentation on theme: "Food Resources Feeding the World."— Presentation transcript:

1 Food Resources Feeding the World

2 Instructions You will need to answer each question on your copy of the PowerPoint provided. Each question is in an orange box. There are 21 questions for this section. You may add extra paper if necessary. You will only be allowed to use your written answers to the questions on the January 27 quiz. Save yourself time and do not write complete sentences. Some of the questions you should be able to answer without using the resource link. Look for the following symbol to click to find answers to the questions: Click

One of six people in developing countries cannot grow or buy the food they need. Others cannot meet their basic energy needs (undernutrition / hunger) or protein and key nutrients (malnutrition).

The root cause of hunger and malnutrition is poverty. Chronic hunger (undernutrition) means not enough calories to be healthy vs. malnourished which means they get the calories, but diet lacks the correct balance of proteins, carbohydrates, vitamins and minerals Food security means that every person in a given area has daily access to enough nutritious food to have an active and healthy life. Need large amounts of macronutrients (protein, carbohydrates, and fats). Need smaller amounts of micronutrients (vitamins such as A,C, and E).

5 Even when people have access to sufficient food, a deficit in just one essential vitamin or mineral can have drastic consequences. What is vitamin A and what does it do? What foods contain vitamin A? What happens if you do not get enough vitamin A or if you get too much vitamin A? Click

6 Solutions: Reducing Childhood Deaths from Hunger and Malnutrition
There are several ways to reduce childhood deaths from nutrition-related causes: Immunize children. Encourage breast-feeding. Prevent dehydration from diarrhea. Prevent blindness from vitamin A deficiency. Provide family planning. Increase education for women.

7 Describe the environmental impacts of the Green Revolution.
In the twentieth century, farming became more mechanized, and the use of fossil fuel energy increased. These changes have led to increasing food output as well as a variety of environmental impacts. Industrial agriculture, or agribusiness, applies the techniques of the Industrial Revolution-mechanization and standardization-to the production of food. Click Describe the environmental impacts of the Green Revolution.

8 Deforestation of tropical rainforest to make room for cash crops

9 Describe the pros and cons of monocropping.

10 The number one use of water worldwide is for agriculture

11 The Ogallala Aquifer What is an aquifer?
Click How much of the irrigated farmland in the U.S. gets water from the Ogallala? What percent is predicted to be depleted by 2060? Click The Ogallala Aquifer ((pronounced OH-GA-LA-LA) Recharge rate is about 0.5 inches per year What are the effects of groundwater depletion? Click

12 Describe the agricultural issues with waterlogging.

13 Can you see the salt crystals?
What is soil salinization? How does salty soils interfere with plant growth? Where does the salt come from? Why is soil salinization more of a problem in arid or semi-arid regions? Click

14 Synthetic – Ammonium Nitrate Fertilizer
Organic Fertilizer Synthetic – Ammonium Nitrate Fertilizer Compare and contrast synthetic fertilizer with organic fertilizer as they relate to the following: source of NPK, advantages, disadvantages, cost, and nutrient distribution. Click

Organisms found in nature (such as spiders) control populations of most pest species as part of the earth’s free ecological services.

We use chemicals to repel or kill pest organisms as plants have done for millions of years. Chemists have developed hundreds of chemicals (pesticides) that can kill or repel pests. Pesticides vary in their persistence. Each year > 250,000 people in the U.S. become ill from household pesticides.

17 Major Types of Pesticides
Type of Pesticide Examples Biomagnified? Chlorinated hydrocarbons DDT, dieldrin, chlordane Yes organophosphates Malathion, parathion, diazinon No Botanicals Rotenone, camphor Contact Herbicides Paraquat Systemic Herbicides 2,4-D, Roundup Fungicide Methyl bromide Fumigant Carbon tetrachloride, ethylene dibromide

18 Bioaccumulation What were the four advantages for using DDT?
Differentiate between bioaccumulation and biomagnification. Click Bioaccumulation describes the way pollutants enter an ecosystem. Many human activities, such as pesticide use and coal-burning, introduce such harmful substances as DDT, methylmercury and other organic chemicals into the environment. These substances are collectively known as Persistent Bioaccumulative Toxic substances, or PBTs. Bioaccumulation occurs when a PBT enters an organism—through breathing, ingestion, or skin contact—more quickly than the substance can leave the organism. The organism now has a higher concentration of the substance than the surrounding environment. Source:

Which disadvantage do you think is the worse? Explain.

20 Explain the connection between Roundup and pig weed.
Superpests Explain the connection between Roundup and pig weed. Click Pig weed

21 Additional Examples of Superpests
Stink bugs in California – resistant to pesticides (people use shovels to remove them from around their homes Pesticide-resistant kudzu beetle causing problems in south Georgia by eating our soybean crops

22 What is a pesticide treadmill?

23 The ideal Pesticide The ideal pest-killing chemical has these qualities: Kill only target pest. Not cause genetic resistance in the target organism. Disappear or break down into harmless chemicals after doing its job. Be more cost-effective than doing nothing.

24 Pesticides Kill Natural Pest Enemies and Create New Pests
Broad-spectrum pesticides kill natural predators New pests are unleashed once natural predators eliminated Currently 100 of the 300 most destructive insect pests in the U.S. were secondary pests

25 Where do pesticides go? Bottom sediments Surface water Groundwater Air
Food Humans Wildlife

26 Each Year in the United States Pesticides Applied to Cropland
Wipe out 20% of the U.S. honeybee colonies and damages another 15% Kill more than 67 million birds Kill 6 – 14 million fish (runoff from croplands) Menace about 20% of the endangered and threatened species in the U.S.

27 This sturgeon shows both male and female reproductive organs
Endocrine Disruptors What are endocrine disruptors? What are sources of endocrine disruptors? How can endocrine disruptors affect my health? Click This sturgeon shows both male and female reproductive organs

28 Pesticide Protection Laws in the U.S.
The Environmental Protection Agency (EPA), the Department of Agriculture (USDA), and the Food and Drug Administration (FDA) regulate the sales of pesticides under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA). The EPA has only evaluated the health effects of 10% of the active ingredients of all pesticides.

29 Other Ways to Control Pests
There are cultivation, biological, and ecological alternatives to conventional chemical pesticides. Fool the pest through cultivation practices. Provide homes for the pest enemies. Implant genetic resistance. Bring in natural enemies. Use pheromones to lure pests into traps. Use hormones to disrupt life cycles.

30 Other Ways to Control Pests
Biological pest control Wasp parasitizing a gypsy moth caterpillar. She will then lay her eggs inside caterpillar and when babies hatch they eat their way out

31 Advantages of Biological Control
Focuses on selected target species Is nontoxic to other species Can be self-perpetuating Minimizes genetic resistance

32 Disadvantages of Biological Control Agents
Can take years of research Cannot always be mass-produced Often are slower acting and more difficult to apply Must be protected from pesticides sprayed close by Can multiply and become pests themselves

33 Other Ways to Control Pests
Genetic engineering can be used to develop pest and disease resistant crop strains. Both tomato plants were exposed to destructive caterpillars. The genetically altered plant (right) shows little damage.

34 Integrated Pest Management (IPM)
Define IPM. How do farmers implement IPM to control pest species? When will the farmers use chemicals if they are using IPM? Why? Why is it important to understand the pest life cycle? Click


36 Which of the following practices is NOT part of integrated pest management?
Crop rotation Elimination of pesticides Use of pest-resistant crops Introduction of predators Frequent inspection of crops

37 Industrial Food Production: High Input Monocultures
Livestock production in developed countries is industrialized: Feedlots are used to fatten up cattle before slaughter. Most pigs and chickens live in densely populated pens or cages. Most livestock are fed grain grown on cropland. Systems use a lot of energy and water and produce huge amounts of animal waste.

38 PRODUCING MORE MEAT About half of the world’s meat is produced by livestock grazing on grass. The other half is produced under factory-like conditions (feedlots). Densely packed livestock are fed grain or fish meal. Eating more chicken and farm-raised fish and less beef and pork reduces harmful environmental impacts of meat production.

39 PRODUCING MORE MEAT Which animal is cheaper to raise and has less impact on the environment? List in order from requiring most feed to least feed to produce a pound of flesh: turkey, chicken, beef, fish, pork

40 Concentrated Animal Feeding Operations (CAFOs)
Cattle Chickens Pigs CAFOs = Animal Feedlots

41 What looks like small ants are cows
Waste Lagoon If you eat…you must excrete. The largest cattle feedlot in Nebraska is located in Broken Bow. On 600 acres of land you will find 85,000 head of cattle. How many cattle is that per acre? Remember the front lawn of Milton is about one acre.

42 The effluent here is hog waste
Below – hog waste spills from busted dam on waste lagoon The waste from these lagoons are sprayed on the fields of bermuda hay as a natural fertilizer Describe the following pollutants produced by CAFOs: pathogens, pharmaceuticals, excessive nutrients, and harmful gases. Click

43 Trade-Offs Animal Feedlots Advantages Disadvantages Increased meat production Need large inputs of grain, fish meal, water, and fossil fuels Higher profits Concentrate animal wastes that can pollute water Less land use Reduced overgrazing Reduced soil erosion Antibiotics can increase genetic resistance to microbes in humans Help protect biodiversity Which single advantage and which single disadvantage do you think are the most important? Support your answer. Figure 13.21 Trade-offs: advantages and disadvantages of animal feedlots. QUESTION: Which single advantage and which single disadvantage do you think are the most important?

44 More sustainable animal farming
Not all meat comes from CAFOs. Free-range chicken and beef are becoming more popular in the U.S. Free-range meat, if properly produced, is more likely to be sustainable than meat produced in CAFOs. Because the animals are not as likely to spread disease as when they are kept in close quarters, the use of antibiotics and other medications can be reduced or eliminated. The animals graze or feed on the natural productivity of the land so less fossil fuel goes into the raising of free-range meat. The manure and urine are dispersed over the range area where it is naturally processed by detritivores and decomposers in the soil. Compare and contrast free-range cattle with cattle from a feedlot.

45 Biodiversity Loss Soil Air Pollution Human Health Water
Loss and degradation of grasslands, forests, and wetlands Erosion Water waste Greenhouse gas emissions from fossil fuel use Nitrates in drinking water Loss of fertility Aquifer depletion Salinization Increased runoff and flooding from cleared land Pesticide residues in drinking water, food, and air Other air pollutants from fossil fuel use Waterlogging Fish kills from pesticide runoff Desertification Sediment pollution from erosion Contamination of drinking and swimming water with disease organisms from livestock wastes Greenhouse gas emissions of nitrous oxide from use of inorganic fertilizers Figure 13.18 Natural capital degradation: major harmful environmental effects of food production. According to a 2002 study by the United Nations, nearly 30% of the world’s cropland has been degraded to some degree by soil erosion, salt buildup, and chemical pollution, and 17% has been seriously degraded. QUESTION: Which item in each of these categories do you think is the most harmful? Fish kills from pesticide runoff Killing wild predators to protect livestock Surface and groundwater pollution from pesticides and fertilizers Loss of genetic diversity of wild crop strains replaced by monoculture strains Belching of the greenhouse gas methane by cattle Bacterial contamination of meat Overfertilization of lakes and rivers from runoff of fertilizers, livestock wastes, and food processing wastes Pollution from pesticide sprays

46 THE GENE REVOLUTION To increase crop yields, we can mix the genes of similar types of organisms and mix the genes of different organisms. Artificial selection has been used for centuries to develop genetically improved varieties of crops. Genetic engineering develops improved strains at an exponential pace compared to artificial selection. Controversy has arisen over the use of genetically modified food (GMF).

47 Mixing Genes Genetic engineering involves splicing a gene from one species and transplanting the DNA into another species.

48 Genetically modified organisms (GMO) refers to plants or crops that have been modified using molecular biology techniques. These plants are modified in labs or research centers with the intention of enhancing its desired traits such as pest resistance, enhancing nutrition, etc. There are natural methods of doing this however; genetic modification ensures that it can be done precisely and quickly. In addition to plants, now animals are also being genetically engineered. Describe the following benefits of GMOs: pest resistance, tolerance to herbicides, resistance to disease and cold, tolerance to drought and salinity, enhancing nutritional content, and remedy for environmental pollution. Click

49 What do we really know about GMOs?
Which fish do you think has been genetically modified? Describe the risks and controversies of the use of GMOs. Explain the connection between Bt corn and monarch butterflies. Click

50 THE GENE REVOLUTION The winged bean, a GMF, could be grown to help reduce malnutrition and the use of large amounts of inorganic fertilizers.

51 THE GENE REVOLUTION Controversy has arisen over the use of genetically modified food (GMF). Critics fear that we know too little about the long-term potential harm to human and ecosystem health. There is controversy over legal ownership of genetically modified crop varieties and whether GMFs should be labeled.

52 Fish is the third major source of food for humans, after grain and meat. In many coastal areas, particularly in Asia and Africa, fish accounts for nearly all of the animal protein that some people consume. A study in 2006 found that 30% of fisheries worldwide had experienced a 90% decline in fish populations. The decline of a fish population by 90% or more is referred to as a fishery collapse. Why have we seen an increase in ocean harvests over the past 50 years? (four factors) Click

Government subsidies given to the fishing industry are a major cause of overfishing. Global fishing industry spends about $25 billion per year more than its catch is worth. Without subsidies many fishing fleets would have to go out of business. Subsidies allow excess fishing with some keeping their jobs longer with making less money.

54 Overfishing and Extinction: Gone Fishing, Fish Gone
About 75% of the world’s commercially valuable marine fish species are over fished or fished near their sustainable limits. Big fish are becoming scarce. Smaller fish are next. We throw away 30% of the fish we catch. We needlessly kill sea mammals and birds.

55 Sustainable Fisheries Act (1996)
Focus shifted fisheries management from a focus on economic sustainability to a species-sustainability approach Protection of critical marine habitat – important for both commercial fish species and non-target species No fishing until populations recover

56 Aquaculture: Aquatic Feedlots
Raising large numbers of fish and shellfish in ponds and cages is world’s fastest growing type of food production. Fish farming involves cultivating fish in a controlled environment and harvesting them in captivity.

57 Catfish aquaculture in Mississippi
What happens to the fish and the fish “poo” if the river floods?

58 Open ocean aquaculture
Two types of floating cages for aquaculture Closed-circulation aquaculture

59 There are many environmental problems associated with aquaculture
There are many environmental problems associated with aquaculture. Excess fish waste causing algal blooms is just one of those environmental issues.

60 Environmental Risks of Marine Aquaculture
Escape of non-native species Genetically modified organisms New diseases and parasites Sea lice on farm-raised salmon Drugs Antibiotics, hormones used on fish Heavy metals Found in fish meal used for food Fish sewage Unwanted algae problems Hypoxic zones (dead zones)

61 Trade-Offs Aquaculture Advantages Disadvantages
High efficiency Needs large inputs of land, feed, and water High yield in small volume of water Large waste output Destroys mangrove forests and estuaries Can reduce overharvesting of conventional fisheries Uses grain to feed some species Low fuel use Dense populations vulnerable to disease Tanks too contaminated to use after about 5 years High profits Profits not tied to price of oil Which of the following disadvantages do you think is the worse? Explain. Figure 13.24 Trade-offs: advantages and disadvantages of aquaculture. QUESTION: Which two advantages and which two disadvantages do you think are the most important?


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