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Ch. 10 Notes APES
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This chapter will help you understand: • Challenges of feeding a growing human
population • The Green Revolution • Preserving crop diversity • Strategies of pest management • Pollination • Genetically modified food • Feedlot agriculture • Aquaculture • Sustainable agriculture Today, we are producing more food per person • Food production exceeds population growth • We produce food through technology
★ Fossil fuels, irrigation, fertilizer, pesticides, cultivating more land, genetic engineering • Today, soils are in decline and most arable land is already farmed • By 2050, we will have to feed 9 billion people. Undernutrition and food security • 1 billion people do not have enough to eat
• ____________________________________ = people receive fewer calories than their minimum requirements ★ Due to economics, politics, conflict, and inefficiencies in distribution
• Most undernourished live in ___________________________________________________________ ★ But 36 million Americans are “food insecure”
• ____________________________________ = guarantee of an adequate, safe, nutritious, and reliable food supply Food security • Undernutrition decreased between 1970 and 1990 • Higher food prices (2006–2008) and the economic slump (2008–2009) increased the number and
percent of hungry • 15% of the world’s population is hungry Overnutrition and malnutrition
• ____________________________________ = receiving too many calories each day ★ Developed countries have abundant, cheap junk food, and people lead sedentary lives ★ In the U.S., 25% of adults are obese ★ Worldwide, over 400 million people are obese
• ____________________________________ = a shortage of nutrients the body needs ★ The diet lacks adequate vitamins and minerals ★ Can lead to diseases
Malnutrition can lead to diseases
• ____________________________________ = diet lacks protein or essential amino acids ★ Occurs when children stop breast-feeding ★ Bloated stomach, mental and physical disabilities
• ____________________________________ = protein deficiency and insufficient calories ★ Wasting or shriveling of the body
The Green Revolution increased yields
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• Depended on lots of: ★ Synthetic fertilizers ★ Chemical pesticides ★ Irrigation ★ Machinery
Consequences of the Green Revolution • From 1900 to 2000, cultivated
area increased 33% ★ While energy inputs increased
80 times • Positive effects on the
environment
★ Prevented some
_____________________________________________________________________ ★ Preserved biodiversity and ecosystems
• Negative effects on natural resources ★ Pollution, erosion
★ ________________________________________________________________________ The Green Revolution • Intensified agriculture saved millions from starvation
★ Turning India into a grain exporter • Rich farmers with lots of land benefited
★ Poor farmers were driven off the land into cities • Today, yields are declining in some Green Revolution areas Monocultures increase output, but at a cost
• ____________________________________ = large expanses of a single crop ★ More efficient, increases output ★ Devastates biodiversity ★ Susceptible to disease and pests
• Human diet is narrowed: 90% of our food comes from _____ crop and _____ livestock species Biofuels affect food supplies • ____________________________________ = are derived from organic materials
★ Replace petroleum in engines • ____________________________________ = a biofuel derived from corn
★ 2007 subsidies doubled production ★ Food prices increased ★ Farmers sold corn for ethanol, not food
• Farmers planted biofuels, not food crops ★ Riots erupted in many nations
Preserving crop diversity: insurance against failure • Preserving native variants protects against crop failure
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• Monocultures are vulnerable ★ Wild relatives contain genes that can provide
resistance to disease and pests • We have lost a great deal of genetic diversity in crops
★ U.S. crops have decreased _____ % in diversity • Market forces discourage diversity in food’s appearance
★ Food producers prefer uniform, standardized food Seed banks are living museums • ____________________________________ = institutions that
preserve seed types as living museums of genetic diversity ★ Seeds are collected, stored, and periodically planted
• The “doomsday seed vault” in Norway stores millions of seeds from around the world
We have thousands of pesticides • Pest = any organism that damages valuable crops
• ____________________________________ = any plant that competes with crops
• ____________________________________ = poisons that target pest organisms ★ Insecticides = kill insects ★ Herbicides = kill plants ★ Fungicides = kill fungi
• 400 million kg (900 million lb) of pesticides are applied in the U.S. each year
★ _____% of this is applied to agricultural land Pests evolve resistance to pesticides • Some individuals are genetically immune to a pesticide
★ They ________________________________________________________________________ • Pesticides stop being effective
★ ____________________________________ = chemists increase chemical toxicity to compete with resistant pests
• Pesticides also kill ____________________________________ ★ Including predators and parasites of pests ★ Pest populations become harder to control
Pesticide resistance • Over 556 insect species are resistant to 300 pesticides
★ Weeds and plant diseases have evolved resistance to pesticides
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Biological control (biocontrol) • ____________________________________ = uses a pest’s predators to control the pest
★ Reduces pest populations without chemicals • _________________________________________________ (Bt) = soil bacteria that kills many pests Biocontrol agents may become pests • It is risky to introduce an organism from a foreign ecosystem into a new ecological context
★ The effects of an introduced species are unpredictable • The agent may have “nontarget” effects on the environment and surrounding economies
• Removing a biocontrol agent is harder than ______________________________________________ ★ Biocontrol use must be carefully planned and regulated
Integrated Pest Management (IPM) • Techniques to suppress pests:
★ Biocontrol ★ Chemicals, if necessary ★ Population monitoring ★ Habitat alteration ★ Crop rotation and transgenic
crops ★ Alternative tillage methods ★ Mechanical pest removal
We depend on insects to pollinate crops
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• Not all insects are pests; some are absolutely vital
★ ______ crop species rely on insect pollinators
• ____________________________________ = male plant sex cells fertilize female sex cells ★ By wind or animals
• Pollinators include: ★ Hummingbirds ★ Bats ★ Insects (bees, wasps, etc.)
• Flowers are evolutionary adaptations to attract pollinators
Conservation of pollinators is vital • Populations of pollinators (e.g., bees) have
plummeted
• _______________________________________ = entire beehives have vanished ★ Unknown causes—Insecticides?
Parasites? Stress? • Reducing or eliminating pesticide use and
planting flowering plants will help preserve bees
• Bees pollinate over 100 crops and contribute $15 billion in services/year
Genetically modified organisms
• ____________________________________________ = laboratory manipulation of genetic material ★ Add, delete, modify DNA
• Genetically modified (GM) organisms = organisms that have been genetically engineered by
★ ____________________________________ DNA = DNA created from multiple organisms Biotechnology is impacting our lives
• ____________________________________ = the application of biological science to create products derived from organisms
• ____________________________________ = an organism that contains DNA from another species ★ Transgenes = the genes that have moved between organisms
• Biotechnology has created medicines, cleaned up pollution, and dissolved blood clots
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Genetic engineering versus agricultural breeding
• ___________________________________________________ = changes organisms through selective breeding of the same or similar species ★ Works with organisms in the field ★ Genes come together on their own ★ Uses the process of selection
• Genetic engineering = mixes genes of different species ★ Works with genetic material in the lab ★ Directly creates novel combinations of genes
★ Resembles the process of ____________________________________ Biotechnology is changing our world • GM foods are a big business
• Most GM crops are _____________________________________________________________________ ★ Large-scale farmers grow crops more efficiently ★ Most U.S. corn, soybeans, cotton, and canola are genetically modified
• Globally, 14 million farmers grew GM foods on 134 million ha What are the impacts of GM crops?
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• As GM crops expanded, scientists, citizens, and policymakers became concerned ★ Impacts on human health
• Concerns over escaping transgenes
★ They could harm _________________________________
★ Pests could ______________________
_________________________________
★ They could ruin the integrity of native ancestral races and interbreed with closely related wild plants
Genetic engineering has benefits and risks • Environmental benefits of genetic engineering:
★ Reduced use of chemical insecticides ★ Increased no-till farming ★ Decreased irrigation, deforestation, land conversion
• Negatives of genetic engineering: ★ Increased herbicide use affects health and habitats ★ Some GM fields support less biodiversity
• _________________________________________________ = don’t undertake a new action until the effects of that action are understood
The GM debate involves ethics • People don’t like “tinkering” with the food supply • With increasing use, people are forced to use GM
products, or go to special effort to avoid them • Multinational corporations threaten the small farmer • Research is funded by corporations that profit if GM foods
are approved for use • GM crops have not eradicated hunger
★ GM crops do not focus on increased nutrition, drought tolerance, etc.
• The GM industry is driven by market considerations driven by financial interests of corporations. GMO producers are suing farmers • Corporations go to great lengths to protect their GM investments The future of GM foods • Europeans demand that GM foods are labeled • U.S. consumers have mostly accepted GM crops
★ They don’t realize most food contains GM products • The U.S. sued the European Union before the World Trade Organization for hindering free trade
• The ____________________________________ on Biosafety lays out guidelines for open information about exported crops ★ The U.S. has not joined
Consumption of animal products is growing • As wealth and commerce increase, so does meat, milk, and egg consumption • Since 1950, global meat production has increased fivefold and per capita meat consumption has
doubled
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Our food choices are also energy choices
• Eating meat is far __________________________ than eating crops
• _____ % of energy is lost from one trophic level to the next
• Eating lower on the food chain feeds more people
• Some animals convert grain into meat more efficiently than others
Environmental ramifications of eating meat
• ____________________________________ are needed to raise food for livestock • Producing eggs and chicken meat requires the least space and water
★ Producing ____________ requires the most Resources needed for livestock production • When we choose what to eat, we choose how we use resources. Feedlot agriculture • Feedlots (factory farms) = also called Concentrated Animal Feeding Operations (CAFOs) • Huge warehouses or pens deliver food to animals living at extremely high densities
★ Over half of the world’s pork and most of its poultry • U.S. farms house hundreds of thousands of debeaked chickens in crowded cages High consumption leads to feedlot agriculture
• Traditional agriculture keeps livestock on ____________________________________
• Feedlot animals are fed _________________________________________________________________ ★ One-third of the world’s cropland is fed to livestock
• Feedlot agriculture allows economic efficiency ★ Greater production of food ★ Unavoidable in countries with high meat consumption, like the U.S.
• Reduced grazing impacts on the land ★ Manure can be applied to fields as fertilizer
Livestock agriculture pollutes water and air
• Feedlots produce huge amounts of ____________________________________
★ Causing ___________________________________ ★ Waterborne pathogens sicken people
• Crowded, dirty housing causes outbreaks in disease
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★ Heavy use of antibiotics, hormones, heavy metals
★ Chemicals are transferred to people ★ Microbes evolve resistance to antibiotics
• Air pollution: ______________________________________ ★ More greenhouse gases (CO2, methane,
nitrous oxides) than automobile emissions
We raise fish on “fish farms” • World fish populations are plummeting
★ Technology and increased demand
• ____________________________________ = raising aquatic organisms in a controlled environment ★ Species are raised in open-water pens or
land-based ponds Aquaculture is growing rapidly • Over 220 freshwater and marine species are
grown • The fastest-growing type of food production
★ Provides ¾ of the world’s fish, ½ of the shellfish
★ Most widespread in Asia The benefits and drawbacks of aquaculture • Benefits:
★ A reliable ____________________________________ source
★ Can be sustainable ★ Reduces pressure on overharvested wild fish
★ Energy ____________________________________ • Drawbacks:
★ Diseases require ____________________________________
★ Lots of ____________________________________ ★ Uses grain ★ Escaped GM fish introduce disease or outcompete wild
fish Sustainable agriculture • Industrial agriculture may seem necessary
★ But less-intensive agricultural methods are better
• ____________________________________ agriculture = does not deplete soil, pollute water, or decrease genetic diversity
• ____________________________________ agriculture = uses smaller amounts of pesticide, fertilizers, growth hormones, water, and fossil fuels than industrial agriculture
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• Organic agriculture = uses no synthetic fertilizers, insecticides, fungicides, or herbicides ★ Relies on biological approaches (e.g.,
composting and biocontrol) Organic approaches reduce inputs and pollution • Organic Food Production Act (1990) establishes
national standards for organic products
★ The USDA issued criteria in 2000 by which food could be labeled organic
• Some states pass even stricter guidelines for labeling - California, Washington, Texas • Nearly 500 organizations offer certification services The benefits of organic farming • Farmers have lower input costs, enhanced income, reduced chemical pollution, and soil degradation
★ They practice stewardship to the land
★ Obstacles include ____________________________________________________________________
• Consumers are concerned about pesticide’s ____________________________________ ★ They want to improve environmental quality ★ Obstacles include the higher price of organics
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Organic agriculture is booming • Organic farmers can’t keep up with demand • Production is increasing • In 1993, the European Union adopted a policy supporting farmers financially during conversion to
organic farming • The U.S. offers no support so organic production lags
★ The 2008 Farm Bill gives $112 million over 5 years for organic agriculture ★ Many farmers can’t switch, because they can’t afford the temporary loss of income ★ In the long run, organic farming is more profitable than conventional farming
Locally supported agriculture is growing • Sustainable agriculture reduces fossil fuel use from long-distance transport of products
★ Food is chemically treated for freshness and color • Farmers’ markets = provide fresh, locally grown food
• ____________________________________ (CSA) ★ Consumers pay farmers in advance ★ Consumers get fresh food ★ Farmers get a guaranteed income
Sustainable agriculture mimics natural ecosystems • Ecosystems operate in cycles
★ Stabilized by _____________________________________________________________ • Small-scale Japanese farmers add ducks to rice fields
★ Ducks eat weeds, insects, snails ★ Their waste is fertilizer ★ Their paddling oxygenates the water ★ Fish and ferns provide food and habitat
Conclusions • Industrialized agriculture has relieved pressures on the land
★ But the environmental consequences are severe • To support 9 billion humans, we must shift to sustainable agriculture
★ Biological pest control, organic agriculture ★ Pollinator protection, preservation of native crops ★ Aquaculture ★ Careful, responsible genetic modification of food