Presentation Transcript

1. Food, Soil, and Pest Management
2. Food: Is it an environmental Problem?
3. Pattern of Food Production Methods
4. World Distribution of Crops
5. How is the Worlds food Produced? 10.1 Food Production Food production has increased dramatically since 1950 Grains raised to feed meat source – meat consumption up Technological advances: machinery, high tech fishing boats, inorganic fertilizers, pesticides, irrigation systems and GMO wheat , corn, rice
6. Types of Food Production Industrialized agriculture or high-input agriculture: agribusiness uses fossil fuels, water, commercial fertilizers, and pesticides to produce monocultures 25% of all cropland mostly in developed nations; spread to some developing nations lately Plantation agriculture industrialized agriculture in developing countries crops (bananas, cacao, coffee) grown for export cash crops - grown to be sold in large market
7. Types of Food Production Traditional agriculture- almost 1/2 of all people Traditional subsistence agriculture only enough crops produced for a single families survival uses human labor and draft animals ex. nomadic herding or shifting cultivation in tropics subsistence crops - used by the grower or sold locally Traditional intensive agriculture increased inputs of human, draft effort and fertilizer and water increases yield allows surplus to sell cash crops
8. We depend on three systems for our food supply Croplands provide 77%: Pesticides, fertilizers, irrigation of hot dry lands , rivers dried up Rangelands produce meat from grazing and supply 16% of all world supplies: densely populated feedlots, pens Oceanic Fisheries supply 7% of worlds food: aquaculture ponds and ocean cages
9. By 2050 8.9 billion people to feed – can we sustainably do it? Environmental Degradation of resources and natural services Pollution Lack of water for irrigation Overgrazing Overfishing Poverty – one out of every five does not land to grow or money to buy food
10. Wheat, Rice, and Corn are King More than half our calories There are 19 grains! We eat two. Cropland: ecological and economic services – provides a job for 1 out of 5 peoples Monoculture: when one type of plant is cultivated per acre Biodiversity: the opposite of monoculture- poly-culture: Many types per acre
11. What is the Green Revolution?
12. Second green revolution (developing countries) First green revolution (developed countries) Major International agricultural research centers and seed banks Green Revolutions Fig. 13-6 p. 282
13. The First Green Revolution Increase in crop yield since 1960 THE PROCESS: 1. Develop selectively bred (GMO)monocultures: corn, rice, wheat 2. High yields using large inputs of fertilizers, pesticides, herbicides (25 – 130 bushels a year!) 3. Increase the number of crops grown per year on plot through Multiple Cropping. Good: uses less protected lands Bad: high input, lots of water use,energy efficiency low 1stgreen:developed 2nd green –developing tropics 2-5x normal yields
14. Soil : a renewable resource that can become non-renewable if replacement rate is not fulfilled The nation that destroys its soil destroys itself. Franklin D. Roosevelt Preserving the worlds soil is key to producing enough food to feed the world
15. Land degradation Natural or human induced processes decrease the ability of the land to support crops, livestock, or wild indigenous species.
16. Erosion: Movement of soil Disturbed vegetation soil is not anchored by roots. Human activities: logging, construction, overgrazing,off-road vehicle use, deliberate burning,salinization,compaction Two harmful effects:Loss of soil fertility Sediment: the largest pollutant of our waters
17. Desertification:semiarid lands overexposed to human activities degrading topsoil
18. Salinization and waterlogging Repeated irrigation actually reduces crop productivity by salt buildup in soil and waterlogging. Salt exists in fresh water : 1/5th of all farmland severleysalianated China, India, Pakistan worst US: ¼ is moderately salinated Input: Reduce irrigation/switch to salt tolerant crops: barley,sugarbeet, cotton Output: flush soil, not grow crops for 25 yrs. Underground drainage systems
19. Waterlogging Accumulation of water as farmers attempt to drain
20. Soil Conservation Use soil pptflos
21. Chapter 2: Science Matter and Energy
22. Scientific Theories & Laws Scientific / Natural Law A description of what we find happening in nature over & over in the same way Law of Gravity Scientific Theory Explain natural laws Supported by extensive evidence ***We can’t “prove” anything is absolutely true. There is always some degree of uncertainty.
23. Categories of Science Sound (Consensus) Science Widely accepted by experts in the field Frontier Science Preliminary results that are often still controversial Junk Science Presented as sound science, but has not undergone peer review
24. Throughput Waste Societies pg33-34Resource use automatically adds large amounts of waste, pollution, and low-quality heat to environment High Throughput Industrialized Countries Is an attempt to boost economy No regard for resources or systems Sinks/Reservoirs: areas where resources are stored in earth Low Throughput Reduction of throughput of matter Matter recycling and reuse economy Not wasting matter/energy Recycling,reusing,reducing Creates new jobs Take Lessons from nature!
25. Laws of Thermodynamics First Law thermodynamics Energy can change form – but not be created or destroyed Energy input = Energy Output Either transferred or lost Second Law Thermodynamics Whenever energy changes form – we lose useable energy Becomes degraded-dispersed Decrease ability to do work Low quality energy Becomes heat Is moved around by perpetual resources = even less useable Amount of heat stored in ocean is greater than oil in Saudia Arabia = but dispersed!
26. First Law of Thermodynamics
27. Energy Definition: The ability to do “work” and transfer heat Energy Forms: electrical, mechanical, radiant (light), heat, chemical, nuclear Energy Types: kinetic and potential Electromagnetic radiation: wavelength and energy content Energy Efficiency or productivity: Measure of how much useful work is accomplished by a unit 16% in US performs useful work! 84% Wasted!! So whats the cheapest best way to get more energy?
28. Energy Quality Relative Energy Quality (usefulness) Source of Energy Energy Tasks Electricity Very high temperature heat (greater than 2,500°C) Nuclear fission (uranium) Nuclear fusion (deuterium) Concentrated sunlight High-velocity wind Very high-temperature heat (greater than 2,500°C) for industrial processes and producing electricity to run electrical devices (lights, motors) Very high High-temperature heat (1,000–2,500°C) Hydrogen gas Natural gas Gasoline Coal Food Mechanical motion (to move vehicles and other things) High-temperature heat (1,000–2,500°C) for industrial processes and producing electricity High Normal sunlight Moderate-velocity wind High-velocity water flow Concentrated geothermal energy Moderate-temperature heat (100–1,000°C) Wood and crop wastes Moderate-temperature heat (100–1,000°C) for industrial processes, cooking, producing steam, electricity, and hot water Moderate Dispersed geothermal energy Low-temperature heat (100°C or lower) Low-temperature heat (100°C or less) for space heating Low Fig. 2-10, p. 31
29. Examples of the Second Law Cars: only 20-25% gasoline produces useful energy Ordinary light bulb: 5% energy is useful light, rest is low-quality heat Living systems: quality energy lost with every conversion (Rule of 10)
30. Law of Conservation of Matter When a physical or chemical change occurs no atoms are created or destroyed Matter only changes form There is no Away in throw away!
31. Conservation of Matter & Sustainability Even when we collect / clean pollution from one area, it must still be put somewhere & possibly pollute something else! We will ALWAYS face the problem of what to do with SOME quantity of wastes / pollution.
32. Matter Quality High-quality matter concentrated / near earth surface / great potential for use Low-quality matter dilute or deep underground / little potential for use Material efficiency (resource productivity) total amount of material needed to produce each unit of goods or services
33. Changes in Matter Physical (Change in size / state) Chemical- you will see ,feel, hear, smell the change Chemical Reaction of Burning Carbon In text on page 26
34. Conservation of Matter & Sustainability Even when we collect / clean pollution from one area, it must still be put somewhere & possibly pollute something else! We will ALWAYS face the problem of what to do with SOME quantity of wastes / pollution.
35. Severity of Pollution Depends on: Chemical nature of pollutants Concentration (ppm / ppb / ppt) Persistence – how long it stays in air/water/soil/body/etc
36. 4 Types of Pollutants Degradable (Nonpersistent) Pollutants Broken down by natural processes Biodegradable Pollutants Organisms (usually bacteria) can break down (sewage) Slowly Degradable (Persistent) Pollutants Takes decades or longer to degrade (DDT / Plastics) Nondegradable Pollutants Natural processes cannot break down (lead/mercury/arsenic)
37. Sustainable Economies Reduce throughput (use) of matter & energy Avoid wasting matter & energy resources Recycle & reuse most of our matter resources Stabilize the size of the human population
38. Inputs into Agriculture Systems
39. Farmer John is using a non commercial fertilizer. This will improve the use of chemicals and make him a ____________ contributor a.High Throughput economics b. Low throughput economies c. Matter recycling and reuse economy d. b and c are true
40. Pattern of Food Production Methods
41. The Green Revolution
42. Consequences of Food Production-biodiversity loss
43. Consequences of Food Production- soil
44. Consequences of Food Production- air pollution
45. Consequences of Food Production- water
46. Consequences of Food Production- human health
47. Animal Farming More than 50% of the world’s cropland is used to produce food for animals livestock consume 38% of world’s grain (70% in U.S.!) 14% of topsoil loss is due to grazing 50% of annual water goes toward livestock Cattle produce 12-15% of all methane Livestock produce 21x more waste than humans Much energy is lost in the food chain
48. Fishing
49. Where fish are caught fisheries - concentration of species suitable for harvesting 78% of catch comes from ocean 99% of this taken from coasts 16% aquaculture 10% lakes and rivers (numbers don’t add to 100?)
50. How many are caught? Between 1950 and 1989 the catch increased five-fold coming mostly from an increase in marine catch since 1989, total catch has leveled off, so per capita catch has decreased because of pop growth
51. Are we causing overfishing? Fish are a renewable resource as long as the annual yield leaves enough fish to replace the loss - sustainable yield prolonged over fishing leads to commercial extinction - not enough fish to make it profitable 15 of 17 major fisheries have been fished at or above sust. Yield since 1993 70% of world’s fish stocks are exploited, over fished or recovering decline is also due to loss of habitat - estuaries are major hatcheries
52. What about aquaculture? Amounts to 16% of harvest annually farming - fish are grown in controlled env ranching - fish are grown and then released and caught in the wild most production of shrimp, salmon & oysters in world BLUE REVOLUTION - aquaculture may cause same increase as with green rev.
53. Agricultural Policy and Food Aid
54. Agricultural Policy Farming is an uncertain business because of weather, infestations etc. In order to keep food production and farmers going in spite of bad times, most governments help farmers financially Subsidizing - too much, too little, how much? You want to keep farmers going, but in a good year, you can have too much produced
55. Food Aid Food aid has been done since the 60’s in order to help others in other parts of the country Problems not a permanent solution (teach to fish) increases populations where there is no food to support it makes countries dependent decreases domestic production drives food prices down Food aid should be done locally, not globally
56. Alternative Food Sources
57. New food is being produced due to genetic engineering Wheat rice tomatoes
58. Foods traditionally grown in local areas are being adapted for global use Winged bean insects soy beans
59. Nutrition
60. Nutritional Needs 2000-6000 calories per day 40-100g protein (essential amino acids) carbos and fats minerals (calcium, iron, iodine) vitamins ( B1, B2, B3, B6, B12, folic acid, C, A, D, E, K)
61. Lack of food Undernourishment (undernutrition) - receive less than 90% of minimum daily intake over long period Malnourishment (malnutrition) - lack of specific dietary requirements effects are generally greatest in children most are reversable
62. Diseases caused by malnourshment Kwashiorkor - protein deficiency Marasmus - energy and protein deficiency
63. Diseases caused by malnourshment Anemia - insufficient iron, causes weakness Goiter and hyperthyroidism - insufficient iodine, causes low metabolism
64. Diseases caused by malnourshment Others: scurvy (C) pellagra (niacin) rickets (D) etc.
65. Famines Acute shortages of food for many people, resulting in a large-scale loss of life characterized by mass migrations to refugee camps recovery takes a long time