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Food Resources

Food Resources

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Food Resources

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  1. Feeding the World Food Resources

  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

  3. FOOD SECURITY AND NUTRITION • 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).

  4. FOOD SECURITY AND NUTRITION • 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 securitymeans 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. 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. Click Describe the pros and cons of monocropping.

  10. The number one use of water worldwide is for agriculture

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

  12. Click Describe the agricultural issues with waterlogging.

  13. Can you see the salt crystals? Click 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?

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

  15. PROTECTING FOOD RESOURCES: PEST MANAGEMENT • Organisms found in nature (such as spiders) control populations of most pest species as part of the earth’s free ecological services.

  16. PROTECTING FOOD RESOURCES: PEST MANAGEMENT • 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

  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:

  19. PROTECTING FOOD RESOURCES: PEST MANAGEMENT Which disadvantage do you think is the worse? Explain.

  20. 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? Click

  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. 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

  35. 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

  36. 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.

  37. 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.

  38. 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

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

  40. 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.

  41. 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 Click Describe the following pollutants produced by CAFOs: pathogens, pharmaceuticals, excessive nutrients, and harmful gases.

  42. Trade-Offs Animal Feedlots Which single advantage and which single disadvantage do you think are the most important? Support your answer. 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

  43. 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.

  44. Biodiversity Loss Soil Air Pollution Human Health Water Loss and degradation of grasslands, forests, and wetlands Erosion Water waste Nitrates in drinking water Greenhouse gas emissions from fossil fuel use Aquifer depletion Loss of fertility Pesticide residues in drinking water, food, and air Salinization Increased runoff and flooding from cleared land Other air pollutants from fossil fuel use Waterlogging Desertification Fish kills from pesticide runoff 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 Fish kills from pesticide runoff Killing wild predators to protect livestock Surface and groundwater pollution from pesticides and fertilizers Belching of the greenhouse gas methane by cattle Loss of genetic diversity of wild crop strains replaced by monoculture strains Bacterial contamination of meat Overfertilization of lakes and rivers from runoff of fertilizers, livestock wastes, and food processing wastes Pollution from pesticide sprays

  45. 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).

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

  47. 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

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

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