Presentation Transcript

1. Ch. 9 Food and Agriculture

   “This…is the world that has been pulled over your eyes to blind you from the truth.“ - Morpheus, the Matrix (1999)
2. Feeding the World Producing enough food has become a greater challenge as the human population reaches passes 7 billion. Food energy is measured in calories. Undernutrition occurs when someone does not eat enough calories (2200 kcal* is the norm). Adults need on average 1000 calories per day to simply survive. Average of 2200 calories needed for a normal, healthy life. *kcal vs “cal”
3. 3 Types of Nutrients
4. NUTRITION AND FOOD SUPPLIES Chronic Hunger and Food Security About 925 million people are considered chronically undernourishedor malnourished. Most of these are in developing countries. This is about 13% of the world’s population. Poverty is the greatest threat to food security - ability to obtain sufficient food on a daily basis. Theoretically, there should be enough food to supply about 3000 kcal/day to everyone.
5. Hunger Around the World
6. Famines A famine is when large-scale undernourishment occurs in a population. Most of the population is eating less than the daily minimum calories needed (1000 calories) Drought causes more than half of famines. Other significant causes: war and bad governance. Ex: North Korea was reluctant to request foreign assistance after severe flooding in the 1990s.
7. Famines and Foreign Aid Aid from rich countries often can help alleviate famines in the short term. Drawbacks to foreign assistance: Population must crowd together in “food camps” to receive supplies. Lack of sanitation Quick spread of diseases Foreign aid tends to be short-lived as people’s attention moves elsewhere. Ex: Indonesian tsunami of 2004, Hurricane Katrina of 2005, Haiti earthquake of 2009, Pakistan floods of 2010
8. Australia Drought of 2006-2009
9. Australia Drought of 2006-2009
10. Australia Drought of 2006-2009
11. Australia Drought of 2006-2009
12. We Need the Right Kinds of Food Malnourishment - nutritional imbalance caused by a lack of specific dietary components or an inability to absorb or utilize essential nutrients 3 billion people suffer from vitamin, mineral or protein deficiency. Results in illness, reduced mental capacity, developmental abnormality, stunted growth, death
13. Types of Malnutrition Undernutrition– Insufficient caloric intake. Malnutrition - Nutritional imbalance caused by lack of specific dietary components. Overnutrition – A daily intake of calories that is too high, leading to obesity. The most common dietary problem in wealthy countries. Up to 64% of all adult Americans are overweight.
14. Malnutrition Examples Iron deficiency is the most common dietary imbalance in the world. Leads to anemia – insufficient oxygen transported to the brain, muscles, and organs due to low red blood cell count. Symptoms include fatigue, dizziness, headache Increases risk of death in childbirth Good sources of iron: Red meat, eggs, beans, and some green vegetables (spinach, broccoli)
15. Malnutrition Examples Iodine deficiency is another very common type of malnutrition, especially in rural developing areas. Iodine is required for production of thyroid hormones, which control the body’s rate of metabolism. Chronic lack of iodine can slow all parts of normal development, including body size and brain function. Lack of iodine can also cause a goiter, or a swollen thyroid gland. Good sources of iodine: seafood and plant crops from iodine rich soils. Source: Miller Environmental Science, 13th Edition
16. Protein Deficiency Diseases Kwashiorkor - occurs mainly in children whose diet lacks high-quality protein Reddish-orange hair, bloated stomach Marasmus - “To Waste Away” - caused by a diet low in protein and calories Very thin, shriveled
17. Overnutrition People in rich countries eat too much meat, salt, sugar and saturated fat and not enough fiber, vitamins, and minerals. On average, we consume 33% more calories than we need. 62% of Americans are overweight. Obesity is spreading around the world as other people adopt Western lifestyles.
18. Overnutrition
19. 9.2 KEY FOOD SOURCES An estimated 90% of the world’s food calories come from 14 species of plants. Three of those crops deliver a majority of world’s nutrients: wheat, corn, and rice. Main nutrient component of these foods is carbohydrates. The major food staples are all plants. Cheaper and easier to produce. Why? Remember the energy pyramid?
20. Ecological Energy Pyramid
21. World Food Production
22. Meat and Dairy Meat and dairy products are all high in protein, iron, and come from animals. As incomes rise in developing countries, food choices shift towards higher-quality and more expensive foods. 60% of production occurs in lesser developed countries. Meat requires a high amount of grain to produce. 15 pounds of grain to produce 1 pound of meat. CAFO’s – concentrated animal feeding operations. Produce tremendous amount of waste. Requires constant antibiotics.
23. Industrialized Agriculture Much of the food produced in the developed world is the result of industrialized agriculture. Dependent on the use of heavy equipment, fuel, fertilizers, pesticides, and irrigation. Most food is grown as a monoculture, or single-crop farming.
24. Factory Farming and Livestock The industrialization of agriculture applies to the raising of livestock, both for meat and dairy. The traditional method of raising animals in open pasture is now largely a relic of the past, replaced by highly-mechanized large-scale operations.
25. Dairy Production Dairy cows are special breeds chosen for high milk production. About half of the U.S. dairy cows are raised in confined indoor pens. As with other mammals, cows only produce milk for about 10 months after giving birth. Must be continuously impregnated to continue milk production. Female calves are kept within the herd Male calves are usually sent to veal crates.
26. Dairy Production The advantage of raising dairy cattle indoors is that all aspects of their growth, feeding, and behavior can be monitored and controlled. Cows leave their pens twice a day to be milked mechanically.
27. Dairy Production The disadvantage is the rapid spread of disease due to the crowding and high amounts of waste manure. To prevent this, antibiotics are commonly administered to the cattle. Nearly half of all antibiotics used in the U.S. are used in farm animals. Farms may also inject their cattle with Bovine Growth Hormone (BGH) to increase milk production.
28. Antibiotics and Hormones There are significant consequences to the use of additive hormones and antibiotics in cattle feed. Overuse of antibiotics is increases the risk of bacteria evolving resistance to the antibiotic. When this occurs, the antibiotic becomes unusable. The use of BGH has multiple effects: The overall health of the cows is affected: Increased likeliness of mastitis (infection of the udders) Increased rate of lameness Reduced fertility There are also effects on the milk itself: Increased growth hormone in the milk Increased pus in the milk, causing it to go sour more quickly
29. Layer Hens – Egg Production The majority of hens (~95%) that supply eggs are raised in battery cages. These are small cages with slanted floors to drain waste. Hens are confined within small cages their entire life. USDA recommendations for cage size: Cages are usually 16 inches wide and contain 4 hens. The highly restricted movement of the hens leads to unusually aggressive behaviors. Beaks are cut or seared off to prevent fighting.
30. Layer Chickens – Egg Production Chicks that are hatched are sorted by gender; females are kept; the males are killed and discarded. The layer hens are subject to near constant light to encourage greater egg production. Fatigue and mineral depletion are common . Egg production begins to decline when the hens reach about 12 months. At this point they are slaughtered and used in processed foods (soup, flavoring, pet foods, etc) The use of antibiotics and growth hormones is illegal in all poultry.
31. Broiler Hens Broiler hens are chickens bred and raised specifically for meat. They have much larger thighs and breasts than normal; making them very heavy and often unable to stand or walk normally. Broiler chickens are raised in pens instead of cages to prevent bruising. Beaks and toes are removed to prevent fighting. The chickens reach their slaughter weight in about 2 months.
32. Broiler Pens
33. Pigs Pigs are very sensitive animals, prone to sunburn and heat stress. As a result, they are primarily raised indoors in temperature-controlled “hatch pens”. Tails are usually cut off at birth to prevent biting – a common issue in overcrowded pens.
34. Pig Batch Pens
35. Food Additives
36. Food Additives The “Smoking Fry” experiment
37. The Hidden Costs The factory farming process makes food much cheaper than conventional methods. One big downside is an increase in the number of food recalls. 2010 Recalls 228 million eggs ( Salmonella ) 2009 Recalls Nestle Toll House cookie dough ( E.coli ) Pistachios ( Salmonella ) Products containing peanut butter / paste ( Salmonella ) 2008 Recalls Beef recall ( cattle were not inspected properly ) Maple Leaf brand deli meats ( listeriosis )
38. Alternative Production Methods Organic No unnatural feeds or feed additives given to animals. No additives in the final product. Does not address treatment of animals Cage Free Chickens are not kept within cages, but may still be high-density indoor pens. Certified Humane Chickens are uncaged and “must be able to perform natural behaviors such as nesting”. Free Range Animals are kept outdoors and allowed to roam.
39. Seafood Seafood is the biggest protein source in many island and coastal countries. Annual catches of ocean fish rose by 4% annually between 1950-1988. Many areas of ocean are now so overharvested that large-scale fishing is unsustainable. If current practices continue, the world’s fisheries will be exhausted by 2048. Nearly half of seafood harvested is now farmed.
40. Seafood Aquaculture supplies food, but it uses wild populations to stock and feed captive populations destroys mangrove forests and wetlands used as nurseries for all marine species allows the spread of disease releases large quantities of feces, antibiotics and other pollutants
41. Food Consumption Differences
42. Food Consumptions Differences
43. World Food Consumption