Bellringer: (packet page 7) Monday December 3 2012 Bellringer: (packet page 7) What are the two types of malnutrition? Which one is more lethal? Protein Energy Malnutrition (PEM) Micronutrient Deficiency Word of the Day: malnutrition: a general term that indicates a lack of some or all nutritional elements necessary for human health PEM Agenda: Bell-ringer Share your Upcycling Projects! Begin lecture: Controversies in Agriculture Homework Change: read article online (Google site) and fill in the chart on 10 reasons to avoid GMOs
Agriculture Conflicts& Controversies Chapter 12
Controversies in Agriculture Genetically Modified Foods Concentrated Animal Feeding Operations Aquaculture Effects of Pesticides
1. Genetically Modified Organisms
Rainbow Cauliflower in Europe via cross-breeding NOT a GMO Crossbreeding and Genetic Engineering Can Produce New Crop Varieties (1) Gene Revolution Cross-breeding through artificial selection Slow process Requires genetic similarity Genetic engineering Genetic modified organisms (GMOs): transgenic organisms Rainbow Cauliflower in Europe via cross-breeding NOT a GMO 5
Crossbreeding and Genetic Engineering Can Produce New Crop Varieties (2) Age of Genetic Engineering: developing crops that are resistant to Heat and cold Herbicides Insect pests Parasites Viral diseases Drought Salty or acidic soil Nematoad resistant bell pepper 6
Advanced tissue culture techniques
The fish “winter flounder” possesses a gene nicknamed the anti-freeze gene. This gene was isolated and inserted into tomatoes, so they could survive a frost during their growing season.
Core Case Study: Grains of Hope or an Illusion? Vitamin A deficiency in some developing countries leads to Blindness Death 1999: Porrykus and Beyer Genetically engineered rice with beta-carotene and more iron 10
Golden Rice: Genetically Engineered Strain of Rice Containing Beta-Carotene 11
TRADE-OFFS Genetically Modified Crops and Foods Projected Advantages Projected Disadvantages Irreversible and unpredictable genetic and ecological effects Need less fertilizer Need less water More resistant to insects, disease, frost, and drought Harmful toxins in food from possible plant cell mutations Grow faster New allergens in food Can grow in slightly salty soils Lower nutrition Figure 12.16 Projected advantages and disadvantages of genetically modified crops and foods. Question: Which two advantages and which two disadvantages do you think are the most important? Why? Increase in pesticide- resistant insects, herbicide- resistant weeds, and plant diseases May need less pesticides Tolerate higher levels of herbicides Can harm beneficial insects Higher yields Less spoilage Lower genetic diversity Fig. 12-16, p. 291
2. Concentrated/Confined Animal Feeding Operations
Meat Production and Consumption Have Grown Steadily Increase in meat production 4x from 1961 to 2007 Expected to double by 2050 More people eating meat as other nations develop Increased meat production = more grain diverted to feedlots Animals are fed primarily grain (corn) and fish More nations will need to import grain to feed the country and the livestock
Efficiency of Converting Grain into Animal Protein
TRADE-OFFS Animal Feedlots Advantages Disadvantages Increased meat production Large inputs of grain, fish meal, water, and fossil fuels Higher profits Greenhouse gas (CO2 and CH4) emissions Less land use Reduced overgrazing Concentration of animal wastes that can pollute water Figure 12.17 Advantages and disadvantages of animal feedlots. Question: Which single advantage and which single disadvantage do you think are the most important? Why? Reduced soil erosion Use of antibiotics can increase genetic resistance to microbes in humans Protection of biodiversity Fig. 12-17, p. 292
Industrialized Meat Production http://www.themeatrix.com/
3. Aquaculture
World Fish Catch, Including Both Wild Catch and Aquaculture
Fish and Shellfish Production Have Increased Dramatically Aquaculture, blue revolution World’s fastest-growing type of food production Dominated by operations that raise herbivorous species Polyaquaculture Incorporating crops and aquaculture: rice, phytoplankton, carp Uses grain for feed
TRADE-OFFS Aquaculture Advantages Disadvantages High efficiency Needs large inputs of land, feed, and water High yield in small volume of water Large waste output Can destroy mangrove forests and estuaries Can reduce overharvesting of fisheries Figure 12.18 Advantages and disadvantages of aquaculture. Question: Which single advantage and which single disadvantage do you think are the most important? Why? Uses grain to feed some species Low fuel use Dense populations vulnerable to disease High profits Fig. 12-18, p. 293
4. Pesticides
Nature Controls the Populations of Most Pests What is a pest? Natural enemies—predators, parasites, disease organisms—control pests In natural ecosystems In many polyculture agroecosystems What will happen if we kill the pests?
Natural Capital: Spiders are Important Insect Predators
We Use Pesticides to Try to Control Pest Populations (1) Insecticides Herbicides Fungicides Rodenticides Study: Pesticide use has not reduced U.S. crop loss to pests Loss of crops is about 31%, even with 33-fold increase in pesticide use
Trade-Offs: Conventional Chemical Pesticides