Download presentation
Presentation is loading. Please wait.
Published byBelinda Reed Modified over 9 years ago
1
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings 10_00-CS.JPG Maize in Oaxaca, Mexico Ch. 10 Agriculture
2
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Transgenic maize in Oaxaca Corn (maize) originated in Oaxaca, Mexico, 5,500 years ago Oaxaca – center for preservation of cultivars In 2001, transgenes from U.S. appeared in Oaxacan maize Disappeared? Teosinte
3
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings 10_01.JPG
4
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Today, we are producing more food per person Food Production exceeds population, BUT High input required
5
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Population 9 billion by 2050 Food security = the guarantee of adequate and reliable food supply to all people at all times
6
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Green Revolution – 1940s -From 1900 to 2000, cultivated area increased 33%, while energy inputs increased 80 times! Requires: -Synthetic fertilizers -Chemical pesticides -Irrigation -Heavy equipment Negative effects: -Pollution -Erosion -Salinization -Desertification Norman Borlaug – father of Green Revolution
7
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Monocultures – 1 crop
8
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Herbicides, Insecticides, Fungicides
9
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings 10_07.JPG
10
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Resistance to pesticides Pesticides stop being effective -Evolutionary arms race / pesticide treadmill: chemists increase chemical toxicity to compete with resistant pests
11
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Biological control Biological control (Biocontrol) = uses a pest’s natural predators to control the pest -Reduces pest populations without chemicals -Ladybugs kill aphids -Bacillus thuringiensis (Bt) = soil bacteria that kills many pests forestencyclopedia.net Ksda.gov
12
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Biocontrol agents may become pests themselves Removing an invasive biocontrol agent is harder than halting pesticide use ecorpestcontrol.com http://fireflyforest.net/firefly/2006/07/19/cane-toads-bufo-marinus/
13
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Integrated Pest Management (IPM) uses multiple techniques to suppress (NOT eradicate) pests -Biocontrol -Chemicals, when necessary -Habitat alteration -Crop rotation and transgenic crops -Mechanical pest removal
14
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Not all insects are pests! Pollination = male plant sex cells fertilize female sex cells -By wind or animals Pollinators include: -Hummingbirds -Bats -Insects Flowers are evolutionary adaptations to attract pollinators
15
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings 10_10.JPG
16
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings 10_11.JPG Indonesia
17
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Genetically modified organisms (GMO or transgenic) Genetic engineering = laboratory manipulation of genetic material Genetically modified organisms = organisms that have been genetically engineered by … Recombinant DNA = DNA created from multiple organisms
18
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings 10_14a.jpg
19
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings mono-diglyceride, soya, soja, yuba, TSF (textured soy flour), TSP (textured soy protein), TVP (textured vegetable protein), lecithin, and MSG
20
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings 10_14b.JPG
21
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Genetic engineering Benefits -Increased nutritional content -Increased agricultural efficiency -Rapid growth -Disease and pest resistance Negatives -Risks are not yet well understood -Protests from environmental activists, small farmers, and consumer advocates
22
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings GMOs (Transgenic organisms)
23
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings 10_13r.JPG
24
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Crop diversity and food security How does preserving native varieties protect food security? How do market forces discourage diversity?
25
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Seed Banks Protect Crop Diversity
26
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Eating animal products has significant impacts As wealth and commerce increase, so does consumption of meat, milk, and eggs -Global meat production has increased fivefold -Per capita meat consumption has doubled
27
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Feedlots (factory farms), also called Concentrated Animal Feeding Operations (CAFOs) Concerns?
28
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Benefits of feedlots: -Greater production of food -Important in countries with high levels of meat consumption, like the U.S. -They take livestock off the land and reduces the impact that they would have on it Drawbacks of feedlots: -Contributions to water and air pollution -Poor waste containment causes outbreaks in disease -Heavy uses of antibiotics to control disease
29
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings 10_19.JPG
30
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Sustainable agriculture = does not deplete soil, pollute water, or decrease genetic diversity -Low-input agriculture = uses smaller amounts of pesticide, fertilizers, growth hormones, water, and fossil fuel energy than industrial agriculture -Organic agriculture = Uses no synthetic fertilizers, insecticides, fungicides, or herbicidesOrganic agriculture -Relies on biological approaches (composting and biocontrol)
31
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings 10_T03.JPG
32
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings 10_00CO.JPG
33
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings U.S. Organic
34
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings 10_SBS02-02.JPG
35
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The benefits of organic farming For farmers: -Lower input costs, enhanced income from higher- value products, reduced chemical costs and pollution -Obstacles include the risks and costs of switching to new farming methods and less market infrastructure For consumers: -Concern about pesticide’s health risks -A desire to improve environmental quality -Obstacles include the added expense and less aesthetically appealing appearance of the product
36
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Organic agriculture succeeds in cities Community gardens = areas where residents can grow their own food In Cuba, over 30,000 people work in Havana’s gardens, which cover 30% of the city’s land -Record yields for 10 crops in 1996-1997
37
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings “Localvores” = eat only locally grown food Community-supported agriculture (CSA) = consumers pay farmers in advance for a share of their yield Community gardens = areas where residents can grow their own food
38
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Aral Sea
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.