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Visualizing Environmental Science Agriculture and Food Resources Chapter 7 Chapter 14 [chapter opener image] Copyright © 2014 John Wiley & Sons, Inc. All rights reserved. Maintaining Grain Stocks for Food Security • Food security: having access at all times to adequate amounts and kinds of food needed for healthy, active lives – World grain stocks provide a measure of food security • Grain stocks are grains from previous harvests which provide a cushion against poor harvests and rising costs • What has been the trend in grain stocks over the past three decades? • UN says it should not be below a 70 day supply – The stockpile in 2010 would only have fed the world for 72 days © 2014 John Wiley & Sons, Inc. All rights reserved. World Food Problems • At least 1 billion people in the world lack food for healthy, productive lives – Most live in rural areas of poorest developing countries • 182 million children under age 5 suffer from undernutrition • Undernutrition: a type of malnutrition in which there is underconsumption of calories or nutrients that leaves the body weakened and susceptible to disease • Even if receiving enough calories, undernutrition happens if not enough essential nutrients: protein, vitamins, and minerals • 2 billion people worldwide suffer from micronutrient deficiencies © 2014 John Wiley & Sons, Inc. All rights reserved. Where do undernourished people live? © 2014 John Wiley & Sons, Inc. All rights reserved. World’s Undernourished People © 2014 John Wiley & Sons, Inc. All rights reserved. © 2014 John Wiley & Sons, Inc. All rights reserved. World Food Problems Millions of children suffer from kwashiorkor, caused by severe protein deficiency. Note the characteristic swollen belly, which results from fluid retention. Photographed in Haiti. Globally, millions of adult men and women are hungry. This homeless man is suffering from severe malnutrition and starvation. Photographed in New Delhi, India. Marasmus is progressive emaciation caused by a diet low in both total calories and protein. Symptoms include a pronounced slowing of growth and extreme wasting of muscles. Photographed in Somalia. © 2014 John Wiley & Sons, Inc. All rights reserved. Reasons for Undernutrition & Malnutrition • Main cause of undernutrition is poverty – Infants, children, and elderly are most susceptible to poverty and hunger – Poorest people do not own land to grow food and do not have money to purchase food • Poverty not restricted to developing nations • Solutions: – Increase sustainable production of food – Improve food distribution – Achieve stable population size at a level the environment can support https://www.youtube.com/watch?v=r7OSYrveXCw World Food Problems - Overnutrition • Overnutrition: a type of malnutrition in which there is overconsumption of calories that leaves the body susceptible to disease – Causes: diets high in saturated fats, sugar, and salt – Effects: high blood pressure, obesity, and increased likelihood of diabetes, heart disease, etc. © 2014 John Wiley & Sons, Inc. All rights reserved. World Food Problems - Overnutrition • Location: mostly a problem in highly developed nations and in urban areas of developing nations – As income increases, people can afford more meats and sugars, so paradoxically, their diet can become less healthy even though they are better off financially © 2014 John Wiley & Sons, Inc. All rights reserved. Annual Meat Consumption Which vegetables are most commonly eaten in the U.S.? © 2014 John Wiley & Sons, Inc. All rights reserved. World Food Problems • Food insecurity: condition in which people live with chronic hunger and malnutrition – 22 countries (primarily in sub-Saharan Africa) commonly experience food insecurity • 66 countries are considered low income and food deficient – Cannot produce enough food, or afford to import it © 2014 John Wiley & Sons, Inc. All rights reserved. What percent of U.S. households are considered “food insecure”? © 2014 John Wiley & Sons, Inc. All rights reserved. U.S. Food Insecurity • Food-insecure households (those with low and very low food security) had difficulty at some time during the year providing enough food for all their members due to a lack of resources • In the case of very low food insecurity, the food intake of some household members was reduced and normal eating patterns were disrupted at times during the year due to limited resources Which states have the highest prevalence of “food insecurity”? © 2014 John Wiley & Sons, Inc. All rights reserved. U.S. Food Insecurity • Estimated prevalence of food insecurity in 2012-14 ranged from 8.4% in North Dakota to 22.0% in Mississippi U.S. Food Insecurity • A major type of food insecurity in the United States comes from “food deserts” – An area were populations don’t have access to fresh foods (ex: they don’t live near a supermarket) • http://www.ers.usda.gov/data-products/foodaccess-research-atlas/go-to-the-atlas.aspx World Food Problems • Experts agree that world hunger, population, poverty, and environmental problems are interrelated – Solutions: • control population growth • promote economic development • correct inequitable distribution of resources © 2014 John Wiley & Sons, Inc. All rights reserved. Global Grain Production • Annual world grain production almost doubled from 1970–2011 – But population has grown so that amount per person has not changed – By 2050, farmers will have to grow close to 30% more food to be able to feed the 9.3 billion people expected – Available grain per person varies significantly per country The Principal Types of Agriculture • Industrialized agriculture – Utilized in highly developed and some developing countries © 2014 John Wiley & Sons, Inc. All rights reserved. A Concentrated Animal Feeding Operation (CAFO) in Brazil The Principal Types of Agriculture • Industrialized agriculture – Requires large capital and energy inputs, less land, and less manual labor than traditional methods • Significantly dependent on fossil fuels • Produces high yields • Monoculture cultivation predominates • Soil degradation, pesticide resistance common © 2014 John Wiley & Sons, Inc. All rights reserved. U.S. Corn Productivity and Land Use The Principal Types of Agriculture © 2014 John Wiley & Sons, Inc. All rights reserved. The Principal Types of Agriculture • Subsistence agriculture – Utilized by most farmers in most developing countries – Traditional agricultural methods that depend on labor and a large amount of land • Just enough food to feed farmer and family • Cultivation methods vary depending on area – – – – – Shifting cultivation Slash-and-burn agriculture Nomadic herding Intercropping Polyculture © 2014 John Wiley & Sons, Inc. All rights reserved. Challenges of Agriculture • U.S. has over 120 million hectares (300 million acres) of prime farmland – Has the soil type, growing conditions, available water to produce food, forage, fiber, oilseed crops – Challenges • • • • Decline in farmland Declining numbers of domesticated varieties Continuing to improve crop and livestock yields Addressing environmental impacts © 2014 John Wiley & Sons, Inc. All rights reserved. Challenges of Agriculture • Victim of urbanization, suburban sprawl – Parking lots, housing developments, shopping malls • Farm Bill—1996 – Farmland Protection Program • Voluntary sale of conservation easements to prevent farmland from being converted to non-agricultural uses (30 yrs–forever) • Farmers retain full rights to use their property for farming © 2014 John Wiley & Sons, Inc. All rights reserved. © 2014 John Wiley & Sons, Inc. All rights reserved. Challenges of Agriculture • Global decline in domesticated plant and animal varieties – Replacement of many local varieties with just a few kinds of modern varieties bred for uniformity and maximum production – Loss of genetic diversity of nutritional value, size, color, flavor, resistance to disease, adaptability to climates and soil types – Germplasm conservation • Plant or animal material that may be used in breeding – Seeds, plants, plant tissues of traditional crop varieties – Sperm and eggs of traditional livestock breeds © 2014 John Wiley & Sons, Inc. All rights reserved. Challenges of Agriculture • Increasing crop yields – Scientific advances since 1940s have increased food production dramatically in highly developed countries – Fertilizers, pesticides, higher yield plant varieties Average U.S. wheat yields, 1950-2010 © 2014 John Wiley & Sons, Inc. All rights reserved. Challenges of Agriculture • Green revolution – 1960s—high yield varieties of rice and wheat developed • Traditional rice plant on left—taller, lower grain yield • Hybrid in center (1960s)—higher yield, disease resistant • Rice plant on right (1990s)—high yield, disease resistant; shorter and stronger stalk to support heavier grain production without collapsing © 2014 John Wiley & Sons, Inc. All rights reserved. Challenges of Agriculture • Green revolution – High yield grain varieties required intensive industrial agriculture • In the 1920s, Mexico produced less than 0.7 metric tons/ha • In 1965, Mexico’s wheat production rose to 2.4 metric tons/ha – Criticisms • Has made developing countries dependent on imported technologies at the expense of traditional agriculture – High energy costs – Environmental problems from excessive pesticide and fertilizer use © 2014 John Wiley & Sons, Inc. All rights reserved. Challenges of Agriculture • Post-green revolution era – World’s demand for rice, wheat, corn will continue to increase into the future • Increasing amounts of grain needed for humans, livestock, and biofuel production – Cannot be met without increasing amount of farmland – Freshwater shortages, rising costs of agricultural chemicals, deteriorating soil quality – Scientists think it’s possible to develop higher yield varieties with sufficient investment – Modern agricultural methods must be introduced to developing countries to increase their crop yields © 2014 John Wiley & Sons, Inc. All rights reserved. Challenges of Agriculture • Increasing livestock yields – Hormones promote faster growth • U.S. and Canada farmers use hormones; EU restricts import – Fear that hormones may affect child development, promote cancer • FAO and WHO say hormones found in beef are safe, less than found in normal human bodies – Antibiotics improve livestock weight gain, less disease • Indiscriminate use leads to development of resistant strains of bacteria—reduces antibiotic efficacy in humans • WHO recommended elimination of antibiotic use in livestock – Many European countries have complied; U.S. has not © 2014 John Wiley & Sons, Inc. All rights reserved. Environmental Impacts • Air and water pollution – Use of fossil fuels and pesticides, animal wastes, fertilizers • Reduces biodiversity, harms fisheries, outbreaks of nuisance species • Replacement of family farms with agribusiness conglomerates – Cattle, hogs, poultry grown in feedlots and factories • Air and water pollution • Pesticide (toxic chemicals used to kill pests) resistance – Increasing use of pesticides, residues contaminate food, kills fish and other aquatic species, reduces beneficial soil organisms © 2014 John Wiley & Sons, Inc. All rights reserved. Environmental Impacts • Land degradation – Reduction in the potential ability of the land to support crops/livestock – Soil erosion, compaction, salinization • Habitat fragmentation – Breakup of large areas of habitat into small, isolated patches – Clearing forests, grasslands, draining wetlands © 2014 John Wiley & Sons, Inc. All rights reserved. Environmental InSight • Impacts of industrial agriculture Increasing antibiotic resistance © 2014 John Wiley & Sons, Inc. All rights reserved. Solutions to Agricultural Problems • Moving to sustainable agriculture – Agricultural methods that maintain soil productivity and a healthy ecological balance while having minimal long-term impacts – Also called alternative, or low-input agriculture – Combines modern with traditional techniques • • • • • Diversification of crops and livestock Breeding of resistant varieties, to reduce use of chemicals Water and energy conservation Crop rotation, conservation tillage to preserve soil quality Animal manure and leguminous crops to decrease the need for chemical fertilizers • Not a single program; adapted to local needs/conditions © 2014 John Wiley & Sons, Inc. All rights reserved. Solutions to Agricultural Problems • Second green revolution – Away from high yield, towards long termsustainability – Options and approaches • • • • Organic agriculture Integrated pest management Reduction in intensive agricultural techniques Increasing focus on long-term sustainability of the soil © 2014 John Wiley & Sons, Inc. All rights reserved. Solutions to Agricultural Problems © 2014 John Wiley & Sons, Inc. All rights reserved. EnviroDiscovery A New Weapon for Locust Swarms • Locusts periodically increase in number and swarm across agricultural lands, devastating crops and trees – In 1998, African farmers spayed massive quantities of pesticides, but there was great concern about the adverse ecological and health effects as well as the shortterm costs ($300 million for 1998 swarm) – Non-chemical biological control was developed in response—fungal spores that target only locusts – “Green muscle” environmentally safe and very effective – In 2009, use of this biological control prevented major locust infestation in Tanzania © 2014 John Wiley & Sons, Inc. All rights reserved. Solutions to Agricultural Problems • Genetic engineering – Manipulation of genes to produce a particular effect • E.g., taking a specific gene from one species and placing it into an unrelated species – Revolutionizing agriculture and medicine – Goals—to develop desirable characteristics in crops and livestock (= as traditional breeding) • Has the potential to produce – More nutritious food plants that contain all essential amino acids or that would be rich in vitamins – Resistant to viral diseases, drought, heat, cold, herbicides, salinity, insect pests, etc. © 2014 John Wiley & Sons, Inc. All rights reserved. Potential Benefits of Genetic Engineering • More nutritious food • Tastier food • Disease- and drought-resistant plants that require fewer environmental resources (such as water and fertilizer) • Decreased use of pesticides • Increased supply of food with reduced cost and longer shelf life • Faster growing plants and animals • Food with more desirable traits, such as potatoes that absorb less fat when fried • Medicinal foods that could be used as vaccines or other medicines © 2014 John Wiley & Sons, Inc. All rights reserved. Genetic Engineering • A plasmid, a small circular molecule of DNA, introduces desirable genes from another organism into a plant cell © 2014 John Wiley & Sons, Inc. All rights reserved. Genetic Engineering © 2014 John Wiley & Sons, Inc. All rights reserved. Genetic Engineering © 2014 John Wiley & Sons, Inc. All rights reserved. Genetic Engineering • First GM crops were approved in the U.S. in early 1990s – Since 2000, GM production in developing countries has increased faster than in developed countries – In 2011, developing countries produced half of the world’s GM crop • GM production – More productive farm animals, fast growing hogs and fish – Utilized in the development and production of vaccines against disease organisms – Plants can be modified with genes that protect against insect pests and provide resistance to herbicides © 2014 John Wiley & Sons, Inc. All rights reserved. Genetic Engineering • Concerns about GM foods • In 1999 EU placed moratorium (since lifted) on approvals for all GM foods • EU refused to buy U.S. corn since 80+ percent of U.S. corn is GM – Spreading of GM genes to wild relatives of crop plants may harm natural ecosystems – Worry that consumers may develop allergies to new GM foods (even though routinely tested) – Scientific consensus is that health risks associated with consuming GM varieties is the same as those of consuming traditionally bred varieties – There are still unanswered questions about effects on environment © 2014 John Wiley & Sons, Inc. All rights reserved. © 2014 John Wiley & Sons, Inc. All rights reserved. AquAdvantage Salmon • AquAdvantage Salmon has been genetically engineered to grow more rapidly than its non-GE farm-raised Atlantic salmon counterpart • It contains rDNA that is composed of the growth hormone gene from Chinook salmon under the control of a promoter (a sequence of DNA that turns on the expression of a gene) from another type of fish called an ocean pout © 2014 John Wiley & Sons, Inc. All rights reserved. AquAdvantage Salmon An AquAdvantage® Salmon with a conventionally grown salmon of the same age © 2014 John Wiley & Sons, Inc. All rights reserved. AquAdvantage Salmon AquAdvantage® Salmon grows to market-size using 25 percent less feed than traditional Atlantic salmon on the market today © 2014 John Wiley & Sons, Inc. All rights reserved. Labeling of GM Foods • • • The FDA requires additional labeling of all foods, including foods from genetically engineered sources, when the food products are materially different from their conventional counterparts “Material differences” include changes in features (like nutritional profile) and functional properties The fact that a food is produced through the use of genetic engineering alone does not normally constitute a material fact requiring additional labeling under the Food, Drug, and Cosmetic Act © 2014 John Wiley & Sons, Inc. All rights reserved. What do these food labels mean? • “Natural” • “Organic” • “Cage-free” • “Artisan” http://abcnews.go.com/blogs/lifestyle/2014/02/natural-vs-organic-how-food-labels-deceive/ © 2014 John Wiley & Sons, Inc. All rights reserved. Controlling Agricultural Pests • Pest – Any organism that interferes in some way with human welfare or activity • Some pests compete with us for food, others spread disease • Pesticide – The agent used to reduce pest populations – Can be grouped by target organisms • • • • Insecticides Herbicides Rodenticides Fungicides © 2014 John Wiley & Sons, Inc. All rights reserved. Controlling Agricultural Pests • Benefits of pesticides – Effectively control organisms that spread disease • Malaria, typhus – Protect crops from pests and pathogens • 1/3 of crops are destroyed by pests – Monocultures (single species grown in large areas) amplify effect of pests • Monoculture crops generate very simple ecosystems, pests thrive, lots of food • Complex ecosystems with many species will have predators and parasites that compete with and control pest populations © 2014 John Wiley & Sons, Inc. All rights reserved. Controlling Agricultural Pests • Problems with pesticides – Ideal pesticides • Narrow-spectrum—kills only the intended pest • Readily breaks down into safe materials • Does not move around in the environment – Most pesticides • Broad-spectrum—kills a variety of organisms, including beneficial ones • Do not degrade readily, or break down into other dangerous materials • Move around in the environment—enter water, air © 2014 John Wiley & Sons, Inc. All rights reserved. Controlling Agricultural Pests • Problems with pesticides – Genetic resistance • In the 50 years of wide pesticide use, at least 520 species of insects and mites and at least 84 weed species have evolved genetic resistance to certain pesticides © 2014 John Wiley & Sons, Inc. All rights reserved. Controlling Agricultural Pests • Problems with pesticides – Bioaccumulation – Biological magnification – Natural enemies (beneficial organisms) also die off from pesticide exposure • The resulting fewer natural controls for pests leads to increased pest populations and need for even larger pesticide use for their control – Movement of herbicides into water supplies increases human exposure and slightly elevates cancer risk © 2014 John Wiley & Sons, Inc. All rights reserved. Pesticides • Bioaccumulation: some pesticides are found to build-up over time in the fatty tissues of predators • Ex: DDT in bald eagles • When an organism containing the pesticide is eaten, the chemical is transferred to the consumer • This eventually leads to very high pesticide concentrations at high trophic levels Controlling Agricultural Pests • Alternatives to pesticides – Biological controls • Uses naturally occurring disease organisms, parasites, or predators to control pests – Pheromones/hormones • Natural substance produced by animals to stimulate a response in other members of the species – Reproductive controls – Genetic controls – Quarantine – Irradiation © 2014 John Wiley & Sons, Inc. All rights reserved. Controlling Agricultural Pests • Alternatives to pesticides – Integrated pest management (IPM) • Combination of pest control methods that if used in the right order and at the proper times, keeps the pest population small enough to prevent substantial economic loss © 2014 John Wiley & Sons, Inc. All rights reserved. Controlling Agricultural Pests • Integrated pest management – Combines a variety of methods to control pests • Management, not eradication of pests • Farmers need to be educated on how to minimize pest effects – Important part of sustainable agriculture – Biological and genetic controls are used as much as possible – Conventional pesticides are used sparingly and only if other methods fail – Requires thorough knowledge of life cycles and feeding habits of pests – Few farmers are using IPM, but number is increasing • Applying pesticides is simple • IPM is more complicated, requires more knowledge © 2014 John Wiley & Sons, Inc. All rights reserved. Integrated Pest Management (IPM) Controlling Agricultural Pests © 2014 John Wiley & Sons, Inc. All rights reserved. Case Study • Organic agriculture – No usage of commercial inorganic fertilizers or pesticides – Organic Food Production Act of 1990 • Specifies guidelines for organic production and labeling • Federal standards for organic certification went into effect in 2002 – In 2008, 2 million hectares farmed organically in the U.S. – Rapid growth in organic agriculture in U.S. today © 2014 John Wiley & Sons, Inc. All rights reserved. Case Study • Organic agriculture – Global and U.S. organic agriculture land use and growth © 2014 John Wiley & Sons, Inc. All rights reserved.