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Solutions to Environmental Problems Associated with Food Production Tuesday, November 1st, 2016 BUT, I’m HUNGRY! What can we do? Answer: 1. Adopt sustainable agriculture (low input practices that cost less and are less damaging) 2. Change Food Subsidies 3. Coupled with genetic engineering. 3. Eat new foods #1. What is sustainable agriculture? Two major ways to increase world’s food production: 1. Increase crop yields 2. Increase the amount of land used Sustainable Agriculture Method of growing crops and raising livestock based on organic fertilizers, soil conservation, water conservation, biological pest control, and minimal use of nonrenewable fossil fuel energy. Solutions More Sustainable Agriculture More Less High-yield polyculture Soil erosion Soil salinization Organic fertilizers Biological pest control Integrated pest management Efficient irrigation Perennial crops Crop rotation Water-efficient crops Soil conservation Subsidies for sustainable farming Water pollution Aquifer depletion Overgrazing Overfishing Loss of biodiversity and agrobiodiversity Fossil fuel use Greenhouse gas emissions Subsidies for unsustainable farming Fig. 12-34, p. 310 Organic Food • Produced without synthetic pesticides, herbicides, & fungicides • No GMFs Organic meat/dairy - 100% organically grown feed - Outdoor pasture - No hormones/antibiotics Produce Meat More Efficiently and Humanely • Shift to more grainefficient forms of protein • Beef from rangelands & pastures, not feedlots • Develop meat substitutes; Efficiency of Converting Grain eat less meat into Animal Protein Sustainable Practices A. Diversifying products 1. Crop rotation 2. Conservation tillage 3. Contour plowing B. Low input farming with water/energy conservation C. Natural predator/prey relationships over chemical pesticides D. Natural fertilizers from manure vs. commercial fertilizers #2. Government Agriculture Policy Government Assistance – Keep food prices artificially low – Give farmers subsidies – Eliminate most or all price controls and subsidies and let farmers/fishers respond to market demand Environmentalists think… Use subsidies to reward farmers/fishers/ranchers who: - Protect the soil - Conserve water - Reforest degraded land - Protect and restore wetlands - Conserve wildlife - Practice more sustainable agriculture/fishing/ranching #3 Genetic Engineering • Crossbreeding and artificial selection • Genetic engineering (gene splicing) • Genetically modified organisms (GMOs) What are Genetically Modified Foods? * Genetically Modified Organisms • To increase crop yields, we can mix the genes of similar types of organisms and mix the genes of different organisms. – Artificial selection has been used for centuries to develop genetically improved varieties of crops. – Genetic engineering develops improved strains at an exponential pace compared to artificial selection. Genetically Modified Organisms • GMO- scientists directly alter the genes of organisms including crop plants and livestock • GM crops are modified to be– Herbicide resistant so farmers can spray herbicide on weeds w/o killing their crops – Pest resistant – Ice resistant (strawberries) Genetic engineering is like, and unlike, traditional breeding • Traditional breeding changes organisms through selective breeding of the same or similar species – Works with entire 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 mutation Genetically Modified Organisms Controversy has arisen over the use of genetically modified food (GMF). – Critics fear that we know too little about the longterm potential harm to human and ecosystem health. There is controversy over legal ownership of genetically modified crop varieties and whether GMFs should be labeled. Genetic Engineering • Wild plants/animals genetic diversity • Domesticated plants/animals genetic diversity as certain characteristics are selected for • Genetic diversity means species are more susceptible to new strains of disease, increasing risk of total species loss. Phase 1 Make Modified Gene cell Identify and extract gene with desired trait Identify and remove portion of DNA with desired trait gene DNA Plasmid Remove plasmid from DNA of E. coli E. coli DNA Insert extracted DNA (step 2) into plasmid (step3) Genetically modified plasmid plasmid Insert modified plasmid into E. coli Grow in tissue culture to make copies Phase 2 Make Transgenic Cell Transfer plasmid copies to a carrier agrobacterium A. tumefaciens (agrobacterium) Agrobacterium inserts foreign DNA into plant cell to yield transgenic cell Plant cell Nucleus Host DNA Foreign DNA Transfer plasmid to surface microscopic metal particle Use gene gun to inject DNA into plant cell Phase 3 Grow Genetically Engineered Plant 1) Half the time as conventional crossbreeding 2) Cuts costs 3) Allows insertion of genes from almost any other organism Transgenic cell from Phase 2 Cell division of transgenic cells Culture cells to form plantlets Transgenic plants with new traits Trade-Offs Genetically Modified Crops and Foods Advantages Disadvantages Need less fertilizer Unpredictable genetic and ecological effects Need less water More resistant to insects, disease, frost, and drought Grow faster May need less pesticides or tolerate higher levels of herbicides May reduce energy needs Harmful toxins and new allergens in food No increase in yields More pesticide-resistant insects and herbicide-resistant weeds Could disrupt seed market Lower genetic diversity Fig. 12-18, p. 294 Advantages vs. Disadvantages • May produce food plants that are more nutritious • Develop crops resistant to pests/disease/drought/hot/cold/herbicides/a cidic-basic soils • Develop disease resistant vaccines for livestock • DID YOU KNOW … 2/3 of food products in US markets contain GM crops! #4 Try New Foods Ant Larvae, waterbugs, caterpillers, cockroaches, butterflies, fried ants I DON’T WANT TO EAT BUGS… Can we cultivate more land instead? Not really – most land is marginal land with poor fertility/steep slopes and would require high inputs of fertilizer/water/energy which are expensive. How can we increase crop/stock yields? • In developed countries: – Fertilizer – Pesticides – Selective breeding – Machinery GREEN REVOLUTION: increase food production per acre Increase Livestock Yields by: hormone and antibiotic injections. European Union (EU) banned use due to health concerns BUT US/Canada still use practice Should we continue Green Revolution techniques? – Without fertilizer, water, and pesticides green revolution varieties are no more productive than traditional varieties – Green revolution varieties and their needed inputs cost too much for subsistence farming. – Grain yields are increasing at a much slower pace. – Actual gains from green and gene revolutions may be overstated. – Crop yield may start dropping for a number of environmental reasons. – Increased loss of biodiversity can limit genetic raw material. Tools to reduce hunger & malnutrition • Slow population growth • Reduce poverty • Sustainable agriculture