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Section 5: Food Production, Nutrition and Environmental Effects. How much has food production increased? How serious is undernutrition and malnutrition? How serious of a problem is overnutrition? What are the environmental impacts of our food choices? Can China’s population be fed?.
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Section 5: Food Production, Nutrition and Environmental Effects How much has food production increased? How serious is undernutrition and malnutrition? How serious of a problem is overnutrition? What are the environmental impacts of our food choices? Can China’s population be fed?
Food Production Tripled between 1950 -1985, since then it has leveled off • Africa, former Soviet Union and China seen biggest drops World produced enough food to meet basic needs, but still 1 in 6 do not get enough to meet nutritional needs Poverty, inequality, war, famine, corruption
Human Needs Large amounts of macronutrients (protein, carbs, fats) Small amounts of micronutrients (A, C, E, iron, iodine, calcium) • Chronic under nutrition: disease increase, stunted growth etc. • Malnutrition: can not get enough protein mainly eating corn, rice, wheat • Huge childhood problem
Malnutrition UN Estimates: • 5.5 million each year die prematurely due to effects of under nutrition. • Each day 15,100 people --- 80% of which are children • In U.S. estimates are 11 million do not have access to enough food
World Food Production • Malnutrition vs. Under nutrition • Shortages in developing countries Fig. 14-16 p. 287
Over nutrition Food intake exceeds energy use and causes body fat • Too many calories not enough exercise • Lower life expectancy, heart disease, lower productivity and quality of life • In developed countries it is 2nd leading preventable cause of death after smoking
Environmental Effects of Food Production • Biodiversity loss • Soil degradation See Fig. 14-18 p. 290 • Air pollution • Water shortages and erosion • Human health
Enviro impacts of food production Need to know these page 290
Section 6: Increasing Crop Production What is the gene revolution? What is genetically modified food? Can we continue to increase food supplies? If so, how?
Increasing World Crop Production • Crossbreeding and artificial selection • Genetic engineering (gene splicing) • Genetically modified organisms (GMOs) • Continued Green Revolution techniques • Introducing new foods • Working more land
Cross Breading and Artificial Selection • Done for centuries to produce “improved” crops • Bigger corn and tomatoes • Slow process
Genetic Engineering • Slicing the DNA of one species into another • Quicker • More cost efficient • Allows insertion of almost any species • More than 2/3 of foods in U.S. have GE ingredients • Resistant to heat, drought, pests, salty soil, less fertilizer………
Genetic Engineering • Example: Citrus trees normally take 6 years to produce fruit yield in only 1 • Rice crops that contain more protein or more iron or that can be grown with far less water • Focus so far more on needs of developed countries vs. developing country needs ($$$)
Frankenfoods or Savior • Considerable controversy over GMOs, GMF, GE Foods • What are the unintended consequences? • Can these new species be recalled if there are problems? • “Massive uncontrolled experiment?” • Critics say move slowly • Require labeling of GMF
Can We Continue to Produce MORE • Lack of resources such as water, fertile soil and environmental factors may limit our ability to continue to yield more crops. • Can we just spread the “Green Revolution” around the world to produce more? • Will GE uniformity lead to more vulnerable crops to pests, diseases, harsh weather?
Can We Continue to Produce MORE • Will people be willing to try new foods? (superfoods) • Fried ants or toasted butterflies anyone? • Is irrigating more land the answer? • Is cultivating more land the answer? • Can we grow more food in urban areas? • Why not just waste less food? 70% currently wasted
Section 7: Producing More Meat How are rangelands used to produce meat? Is producing more meat the answer to the world’s food problems? What are the effects of overgrazing? How can meat be produced more sustainable?
Rangelands • Many feel need to increase meat production to feed population • As incomes rise so does meat consumption
Rangelands Are grasslands in temperate and tropical climates that provide foraging and browsing areas for animals • Cattle, Sheep, goats are on 42% of rangeland • Pastures are managed grasslands • Renewable resource
Producing More Meat • Meat products good source of protein • Per capita meat production doubled since 1950 Feedlots: animals are fattened for slaughter in densely populated confined areas CAFOs = 43% world beef
Factory Farms • Cattle, pigs, poultry • As many as 100,000 cattle, 10,000 hogs shoulder to shoulder • What to do with waste? • Open Lagoons? • Consume large amount of grain and fish instead of feeding on grass • Antibiotics and steroid use See page 295 box
Overgrazing Occurs when too many animals graze for too long and exceed the carrying capacity of the grassland area • Kills vegetation • Reduces grass cover • Causes erosion • Compacts soil • Damages watershed • Desertification
Overgrazing: Solutions • Control numbers by figuring out carrying capacity • Move from riparian zones and locate watering hole away from sensitive zones • Move animals around • Replant overgrazed areas and/or use fertilizers
Producing More Meat Kilograms of grain needed per kilogram of body weight Beef cattle 7 Pigs 4 Chicken 2.2 Fish (catfish or carp) 2 • Feedlots • Rangelands • Efficiency Fig. 14-22 p. 297 • Improved rangeland management • Environmental consequences (Connections p. 295)
Section 8: More Fish? Where do we get our fish and shellfish? What are the impacts of over fishing? What is aquaculture?
Catching and Raising More Fish • Fisheries • Fishing methods (See Fig. 14-24 p. 299) • Overfishing • Commercial extinction • Aquiculture • Fish farming and ranching
Where do we get fish and shellfish? Fisheries: concentrations of aquatic species suitable for harvesting from a body of water • 55% from the ocean • Fish and shellfish supply 7% of world’s food • Mostly from coastal zones • Primary source of protein for more than 1 billion (mostly developing countries)
Where do we get fish and shellfish? Aquaculture: using feedlot management to raise marine and freshwater fish. • using cages and nets • Rivers, lakes and oceans • China the world’s leader • 1/3rd of world’s marine fish harvest is used for animal feed, fishmeal and oil
Kilograms of grain needed per kilogram of body weight Beef cattle 7 Pigs 4 Chicken 2.2 Fish (catfish or carp) 2 Efficiency of converting grain to animal protein
How are fish harvested? High Tech Global Fishing Fleets Roam World • Sonar, GPS, spotter planes, huge nets, long fishing lines • Large factory ships catch, process and freeze product
How are fish harvested? Trawling: dragging a funnel shaped net along bottom of sea • Used to catch bottom dwellers • Shrimp, cod, flounder, scallops • Scrapes up everything on bottom leaving it bare • Clear cutting ocean floor Bycatch thrown back
How are fish harvested? Purse-Seine Fishing: Surrounding schools of fish with boats and a huge net to capture entire school • Net drawn in tighter and tighter • Tuna, herring, mackerel • Uses spotter planes often • Led to huge dolphin kills
How are fish harvested? Long lining: putting out lines up to 80 miles long with thousands of hooks • Swordfish, tuna, shark, halibut, cod • Huge bycatch • Endanger turtles, dolphins, whales etc.
How are fish harvested? Drift netting: using huge nets to trap fish • Huge bycatch • Kill many unwanted species • Danger to marine mamals • Since 1992 UN ban driftnets over 1.6 miles in international water (voluntary compliance)
Over fishing • Tragedy of Commons • Not a new problem, but becoming global and tech driven • Commercial Extinction • Adding to the problem are development along the coasts, wetland and estuary pollution, coral reef and mangrove forest destruction • New high demand for “healthy” fish
Aquaculture Raising fish and shellfish for food, like crops • World’s fastest growing food production • What do you think are pros and cons of this technique?