Chapter 10 Topics:  Feeding a growing human population  The Green Revolution  Preserving crop diversity  Pest management  Pollination  Genetically modified food  Feedlot agriculture  Aquaculture  Sustainable agriculture

Trends in food production  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

Under-nutrition  1 billion people do not have enough to eat  Under-nutrition = people receive fewer calories than their minimum requirements  Caused by economics, politics, conflict, and inefficiencies in distribution  Most undernourished live in developing nations but 36 million Americans are “food insecure”  Food security = guarantee of an adequate, safe, nutritious, and reliable food supply

Over-nutrition  Over-nutrition = people receive too many calories  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

Malnutrition  Malnutrition = people receive fewer nutrients than the body needs – the diet lacks vitamins/minerals  Malnutrition leads to diseases  Kwashiorkor = diet lacks protein or essential amino acids  Occurs when children stop breast-feeding  Bloated stomach, mental and physical disabilities

The Green Revolution  Mid- to late 20 th century – Norman Borlaug  The use of new methods and technologies to increase the yield per acre for primary grain crops (wheat, corn, rice)  Depended on lots of:  Synthetic fertilizers  Chemical pesticides  Irrigation  Machinery

Looking back  From 1900 to 2000, cultivated area increased 33% while energy inputs increased 80 times  Positive effects on the environment  Prevented some deforestation and land conversion  Preserved biodiversity and ecosystems  Negative effects on natural resources  Pollution, erosion  Salinization, desertification

India’s experience  Intensified agriculture saved millions from starvation  India became a grain exporter  Rich farmers with lots of land benefited  Poor farmers were driven off the land into cities

Narrowing our diet  The Green Revolution narrowed the human diet: 90% of our food comes from 15 crop and 8 livestock species  Market forces discourage diversity in appearance, preference for uniform, standardized food

Monocultures  Monocultures, a legacy of the Green Revolution  Large plantings of a single crop  Sometimes a single genetic variety!  Can be cost-efficient and increase output  Significantly reduce biodiversity  Susceptible to pests and diseases

Preserving crop diversity  Preserving native variants can help to protect against crop failure  Wild relatives of crops contain genes that can provide resistance to disease and pests  Seed banks = institutions that collect, store, and periodically plant seeds to preserve genetic diversity

Pesticides  Our heavy use of pesticides and the issues this creates are another legacy of the Green Revolution  Pest = any organism that damages valuable crops  Weed = any plant that competes with crops  Pesticides = poisons that target pest organisms  Insecticides = kill insects  Herbicides = kill plants  Fungicides = kill fungi  900 million lbs of pesticides are applied each year  75% of this is applied to agricultural land  $32 billion/year is spent on pesticides worldwide

Issues with pesticides  Pests become resistant to pesticides through the processes of evolution  The “pesticide treadmill” – an escalating cycle of increasing chemical toxicity and ever more resistant pests  556 insect species are resistant to 300 pesticides  Pesticides also kill non-target organisms  Including predators and parasites of pests  Pest populations become even harder to control

Biological control of pests  Biological control uses a pest’s predators to control the pest  Cactus moths control prickly pear  Weevils control water hyacinth  Bacillus thuringiensis (Bt) a soil bacteria that kills many caterpillars and insect larvae

Bio-control can backfire  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 “non-target” effects on the environment and surrounding economies  Removing a bio-control agent is harder than halting pesticide use

Integrated Pest Management (IPM)  The use of multiple techniques to suppress pests:  Biocontrol  Chemicals, if necessary  Population monitoring  Habitat alteration  Crop rotation  Alternative tillage  Mechanical pest removal

The other side of insects  We depend on insects to pollinate crops  800 crop species rely on insect pollinators  Flowers are evolutionary adaptations to attract pollinators  Conservation of pollinators is vital  Bee populations have been plummeting  Colony collapse disorder = entire beehives have vanished – causes as yet unknown  Reducing or eliminating pesticide use and planting flowering plants will help preserve bees

Biotechnology  Biotechnology = the application of biological science to create products derived from organisms  Biotechnology has created medicines, cleaned up pollution, and dissolved blood clots  Biotechnology is now being applied to food, specifically through genetic engineering – laboratory manipulation of genetic material  Genetically modified organisms (GMOs) engineered using recombinant DNA (genes from multiple organisms)  Also called transgenic organisms and transgenes

Traditional breeding vs GMOs  Traditional 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  Genetically modified organisms = genes of different species are mixed  Works with genetic material in the lab  Directly creates novel combinations of genes  Resembles the process of mutation

A growing business…  GM foods are a big business  Most GM crops are herbicide and pesticide resistant  Large-scale farmers grow crops more efficiently  Most U.S. corn, soybeans, cotton, and canola are genetically modified

The environmental pros and cons  Benefits of genetically modified organisms:  Reduced use of chemical insecticides  Increased no-till farming  Decreased irrigation, deforestation, land conversion  Negatives of genetically modified organisms:  Increased herbicide use affects health and habitats  Some GM fields support less biodiversity  The field is very new and questions about long-term human health and environmental effects remain

Science, society, economics, ethics  Science is only part of the GMO story  People don’t like “tinkering” with the food supply  As use grows, people are forced to use GM products, or go to special effort to avoid them  Research is funded by corporations that profit if GM foods are approved for use  Multinational corporations threaten the small farmer  GM crops have not eradicated hunger, they do not focus on increased nutrition, drought tolerance, etc.

Moving forward  U.S. consumers have mostly accepted GM crops  They don’t realize most food contains GM products  Europeans demand that GM foods are labeled  The U.S. sued the European Union before the World Trade Organization for hindering free trade  Brazil, India, and China actively developing GM crops

Animals as food  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

Food choices are energy choices  Eating meat is less energy efficient than eating crops  Eating at lower trophic levels feeds more people  Some animals convert grain into meat more efficiently than others

Food choices are resource choices  Land and water are needed to raise food for livestock  Producing eggs and chicken meat requires the least space and water  Producing beef requires the most

Feedlot agriculture  High consumption leads to feedlot agriculture  Feedlots animals raised in large warehouses or pens at high densities  Concentrated Animal Feeding Operations (CAFOs) raise over half of the pork and most of the poultry

On the one hand…  Traditional agriculture keeps livestock on grasslands  Feedlots reduced grazing impacts on the land  Feedlot animals are fed grain grown on cropland  One-third of the world’s cropland is fed to livestock  Feedlot agriculture allows economic efficiency  Greater production of food, necessary in countries with high meat consumption  Manure can be applied to fields as fertilizer

On the other hand…  Feedlots produce huge amounts of manure and urine  Causing eutrophication  Waterborne pathogens sicken people  Crowded, dirty housing causes outbreaks in disease  Heavy use of antibiotics, hormones, heavy metals  Chemicals are transferred to people  Microbes evolve resistance to antibiotics  Feedlots create air pollution  Odors (ammonia)  Greenhouse gases (CO 2, methane)

Aquaculture  Demand for animal proteins also affects fish  Ocean fish populations are plummeting  Aquaculture raising aquatic organisms in open-water pens or land- based ponds

Current trends  Aquaculture is growing rapidly, widespread in Asia  Over 220 freshwater and marine species are grown  Fastest-growing type of food production  Provides ¾ of the world’s fish, ½ of the shellfish

Benefits and drawbacks  Reliable protein source  Energy efficient  Can be sustainable  Reduces pressure on overharvested wild fish  Antibiotics for disease  Lots of biologic waste  Uses grain  Escaped GM fish outcompete wild fish BenefitsDrawbacks

Sustainable agriculture  Industrial agriculture may seem necessary but less- intensive agricultural methods are better  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 fuels than industrial agriculture  Organic agriculture = uses no synthetic fertilizers, insecticides, fungicides, or herbicides; relies on biological approaches

Organic farming  Organic Food Production Act (1990) establishes national standards for organic products  The USDA issued criteria in 2000 by which food could be labeled organic  Demand & production are increasing  U.S. consumers spend $22.9 billion/year  1.8 million ha of land being organically farmed

Benefits and obstacles  More profitable in the long run – lower input costs, enhanced income,  Farmers practice stewardship of the land – less chemical pollution, less soil degradation  Addresses consumer concerns about pesticide’s health risks  Risks/costs of switching to new methods  Temporary loss of income  The U.S. offers no financial support during the conversion  Organic product cost more in the marketplace

Locally supported agriculture  Farmers’ markets = provide fresh, locally grown food  Community-supported agriculture (CSA)  Consumers pay farmers in advance  Consumers get fresh food  Farmers get a guaranteed income  Local food has a smaller ecological footprint (lower transportation costs)

Mimicking natural ecosystems  Ecosystems operate in cycles  Stabilized by negative feedback loops  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