APES Chapter 12 & 14

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Organic Polyculture

Many organic crops are grown on the same plot of land.

Traditional Intensive Agriculture

farmers increase their inputs of human and draft-animal labor, animal manure for fertilizer, and water to obtain higher crop yields. If the weather cooperates, they produce enough food to feed their families and to sell some for income.

Soil Formation and Weathering

formation begins when bedrock is slowly broken down into fragments and particles by physical, chemical, and biological processes, called weathering.

Manufactured Inorganic Fertilizers

The main active ingredients are phosphorous, nitrogen, and potassium (think of games).

Traditional Subsistence Agriculture

supplements energy from the sun with the labor of humans and draft animals to produce enough crops for a farm family's survival, with little left over to sell or store as a reserve for hard times.

POPs

Stands for: Persistent Organic Pollutants

Irrigation

Supplying water to crops by artificial means. This is one of the technological advances that has occurred recently in agriculture.

Micronutrients

Vitamins such as A, B, C, & E and minerals such as iron and iodine. People need more macronutrients and less micronutrients to stay healthy.

How can we improve food security?

We can improve food security by creating programs to reduce poverty and chronic malnutrition, relying more on locally grown food, and cutting food waste.

How can we protect crops from pests more sustainably?

We can sharply cut pesticide use without decreasing crop yields by using a mix of cultivation techniques, biological pest controls, and small amounts of selected chemical pesticides as a last resort (integrated pest management).

Topsoil Depletion

Although topsoil is a renewable resource, it is renewed very slowly, which means it can be depleted.

Famine

EXTREME food shortage

Crop Factors

Farmers can have a good year or a bad year...it just depends on the factors: weather, crop prices, crop pests and diseases, loan interest rates, and global markets. Governments use two main approaches to influence food production. First, they can control prices by putting a legally mandated upper limit on prices in order to keep food prices artificially low. This makes consumers happy but makes it harder for farmers to make a living. Second, they can provide subsidies by giving farmers price supports, tax breaks, and other financial support to keep them in business and to encourage them to increase food production.

Horizons

Horizontal layers in soil. Each has a distinct texture and composition that vary with different types of soils. soils. Most mature soils have at least three of the four possible horizons.

Genetic Engineering and Gene Splicing

Involves altering an organism's genetic material through adding, deleting, or changing segments of its DNA to produce desirable traits or to eliminate undesirable ones—a process called gene splicing. **No labeling of genetically modified food is required by law.

Windbreaks or Shelterbelts

When farmers establish windbreaks, or shelterbelts, of trees around crop fields to reduce wind erosion. The trees retain soil moisture, supply wood for fuel, increase crop productivity by 5-10%, and provide habitats for birds and for insects that help with pest control and pollination.

Polyculture

When farmers grow several crops on the same plot simultaneously

Waterlogging

When water accumulates underground and gradually raises the water table, especially when farmers apply large amounts of irrigation water in an effort to leach salts deeper into the soil. Waterlogging deprives plants of the oxygen they need to survive. Without adequate drainage, waterlogging lowers the productivity of crop plants and kills them after prolonged exposure.

Reduce Soil Erosion

It takes hundreds of years for fertile topsoil to form. So, sharply reducing topsoil erosion is the single most important component of more sustainable agriculture.

Perennial Crops

Crops that grow back year after year on their own **very hard to kill!

First Generation Pesticides

Chemicals used as pesticides that were mainly borrowed from plants.

Open Ocean Aquaculture

Involves raising fish (large and carnivorous) in underwater pens located offshore.

What is food security and why is it difficult to attain?

Many people in less-developed countries have health problems from not getting enough food, while many people in more-developed countries suffer health problems from eating too much food. The greatest obstacles to providing enough food for everyone are poverty, corruption, political upheaval, war, bad weather, and the harmful environmental effects of industrialized food production.

Community Supported Agriculture

Programs in which people buy shares of a local farmer's crop and receive a box of fruit or veggies each week during the summer and fall. **Growing locally is better!!!!

Key Nutrients for a healthy Human Life

Proteins- Food source is animals and plants; they help to build and repair body tissues Carbohydrates- Source is wheat, corn, and rice; provides short-term energy Lipids (oils and fats)- Source is animals fats, nuts, and oils; helps to build membrane tissues and create hormones.

Principle of Sustainability

Calls for depending on a variety of food sources as an ecological insurance policy for dealing with changes in environmental conditions that have occurred throughout human history. (humans rely on a very small number of species for food and resources...so if the animals and plants were to disappear due to disease or something we would be in big trouble)

Hydroponics

Involves growing plants by exposing their roots to a nutrient-rich water solution instead of soil, usually inside a greenhouse.

Undernutrition or Hunger

People who cannot grow or buy enough food to meet their basic energy needs suffer from chronic undernutrition, or hunger

Narrow or Selective-Spectrum Agents

Pesticides that are effective against a narrowly defined group of organisms.

Compost

Produced when microorganisms in topsoil break down organic matter such as leaves, crop residues, food wastes, paper, and wood in the presence of oxygen

B and C Horizons

The B horizon (subsoil) and the C horizon (parent material) contain most of a soil's inorganic matter, mostly broken-down rock consisting of varying mixtures of sand, silt, clay, and gravel. Much of it is transported by water from the A Horizon. The C horizon lies on a base of parent material, which is often bedrock. The spaces, or pores, between the solid organic and inorganic particles in the upper and lower soil layers contain varying amounts of air (mostly nitrogen and oxygen gas) and water. Plant roots use the oxygen for cellular respiration.

Overnutrition

occurs when food energy intake exceeds energy use and causes excess body fat. Too many calories, too little exercise, or both can cause overnutrition. People who are underfed and underweight and people who are overfed and overweight face similar health problems: lower life expectancy, greater susceptibility to disease and illness, and lower productivity and life quality Today in America, four of the top ten causes of death are diseases related to diet—heart disease, stroke, Type 2 diabetes, and some forms of cancer.

Aquaculture Advantages

- High efficiency - High yield - Reduced over-harvesting of fisheries - Low fuel use - High profits

Animal Feedlots Advantages

- Increased meat production - Higher profits - Less land use - Reduced overgrazing - Reduced soil erosion - Protection of biodiversity

Cerrado

A huge tropical grassland region south of the Amazon basin. This land is being burned or cleared for cattle ranches, large plantations of soybeans grown for cattle feed, and sugarcane used for making ethanol fuel for cars. These activities threaten biodiversity and contribute to projected climate change by releasing large quantities greenhouse gases carbon dioxide, methane, and nitrous oxide into the atmosphere faster than they can be removed by the earth's carbon and nitrogen cycles.

Pesticides

Chemicals used to kill or control populations of organisms that we consider undesirable. Common types of pesticides include insecticides (insect killers), herbicides (weed killers), fungicides (fungus killers), and rodenticides (rat and mouse killers). We did not invent the use of chemicals to repel or kill other species. For nearly 225 million years, plants have been producing chemicals to ward off, deceive, or poison the insects and herbivores that feed on them.

Harmful environmental and health effects of modern agriculture

Crop yields in some areas may decline because of environmental factors such as erosion and degradation of topsoil, depletion and pollution of underground and surface water supplies used for irrigation, emission of greenhouse gases that contribute to projected climate change, and loss of croplands to urbanization.

Macronutrients

carbohydrates, proteins, and fats To maintain good health and resist disease, individuals need fairly large amounts

Polyaquaculture

Operations that raise fish or shrimp along with algae, seaweeds, and shellfish in coastal lagoons, ponds, and tanks. This approach applies recycling and biodiversity.

Chronic Malnutrition

deficiencies of protein and other key nutrients. This weakens them, makes them more vulnerable to disease, and hinders the normal physical and mental development of children.

Green Revolution

A green revolution involves three steps. First, develop and plant monocultures of selectively bred or genetically engineered high-yield varieties of key crops such as rice, wheat, and corn. Second, produce high yields by using large inputs of water and manufactured inorganic fertilizers, and pesticides. Third, increase the number of crops grown per year on a plot of land through multiple cropping --> First Green Revolution in the US and other more developed countries.

Asphalt Gardening

A growing practice where people grow food on rooftops, patios, balconies, etc. in cities

Borneo and Consequences w/ pesticides

Borneo (1955) had a malaria problem--> the WHO sprayed the island with a DDT similar chemical--> insects began to die--> after eating the insects, the lizards began to die--> cats began to die because they ate the lizards--> rat infestation because all the cats were gone--> people threatened with plague the rats carried--> the WHO parachuted cats back onto the island--> people's roofs began to cave in because of the caterpillar who fed on the roof's predators were all dead Reminds us that when we intervene in nature, our actions always have consequences.

Industrialized Meat Production has harmful Environmental Consequences

Brazil is the world's largest exporter of beef. The biggest threat to Brazil's Amazon Forests is the clearing and burning of the wildlife in these forests to make way for the cattle ranches. Fossil fuel energy (mostly from oil) is also an essential ingredient in industrialized meat production. Using this energy pollutes the air and water and emits greenhouse gases that contribute to projected climate change. Another growing problem is the use of antibiotics in industrialized livestock production facilities. Antibiotics are used in agriculture to feed as an effort to prevent the spread of diseases in crowded feedlots and CAFOs and to make the livestock animals grow faster. It can reduce the effectiveness of some antibiotics used to treat infectious diseases in humans and promote the development of new and aggressive disease organisms that are resistant to all but a very few antibiotics currently available. In 2009, the U.S. Centers for Disease Control and Prevention reported that antibiotic-resistant infections killed about 65,000 people in the United States—more than the number of deaths from breast and prostrate cancer combined.

Green Manure

Consists of freshly cut or growing green vegetation that is plowed into the topsoil to increase the organic matter and humus available to the next crop.

Case Study: Raising Salmon in an Artificial Ecosystem

Cooke aquaculture is one of the largest salmon producers of eastern Canada. The farm employs polyaquaculture by raising 3 different species that interact much as they do in nature. Structures with blue mussels and rafts with dangling kelp. Turns pollutants such as fish waste into resources by mimicking a natural ecosystem.

Gene Revolutions (1 & 2)

Crossbreeding animals and plants, artificial selection, genetic engineering, etc.

Soil

a complex mixture of eroded rock, mineral nutrients, decaying organic matter, water, air, and billions of living organisms, most of them microscopic decomposers. All terrestrial life depends on soil. It supplies most of the nutrients needed for plant growth and purifies and stores water, while organisms living in the soil help to control the earth's climate by removing carbon dioxide from the atmosphere and storing it as organic carbon compounds, as part of the carbon cycle.

Fishery

a concentration of particular aquatic species suitable for commercial harvesting in a given ocean area or inland body of water. Scientific studies have estimated that at least 63% of the world's ocean fisheries are being depleted or overexploited. According to a 2006 FAO study and research by a number of fishery scientists, unless we reduce overfishing and ocean pollution and slow projected climate change, most of the world's major ocean fisheries could collapse sometime during this century.

Terracing

A way to grow food on steep slopes without depleting its topsoil. It is done by converting steeply sloped land into a series of broad, nearly level terraces that run across the land's contours. The terraces retain water for crops at each level and reduce topsoil erosion by controlling runoff.

Aquaculture Disadvantages

- Large inputs of land, water, and feed - Large waste output - Loss of mangrove forests and estuaries - Some species fed with grain, fish meal, or fish oil - Dense populations vulnerable to disease

Genetically Modified Food Advantages

- Need less fertilizer - 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

Syntheitc Pesticides Advantages

- Save human lives - Helped us increase food supply - Increase profit for farmers - Work fast - When used properly, the health risks of some pesticides are very low, relative to their benefits - Newer pest control methods are safer and more efficient than many older ones

Genetically Modified Foods Disadvantages

- Unpredictable genetic and ecological effects - Harmful toxins and new allergens in foods - No increase in yields - More pesticide-resistant insects and herbicide-resistant weeds develop - Could disrupt seed market - Lower genetic diversity - We know too little about the long-term potential harm to human health and ecosystems from the widespread use of such crops. For example, genes in plant pollen from genetically engineered crops can spread among nonengineered species. The new strains can then form hybrids with wild crop varieties, which could reduce the natural genetic biodiversity of wild strains.

What environmental problems arise from industrialized food production?

Future food production may be limited by soil erosion and degradation, desertification, water and air pollution, climate change from greenhouse gas emissions, and loss of biodiversity.

Farmers have two ways to produce more food:

farming more land or getting higher yields from existing cropland.

Aquaculture

the practice of raising marine and freshwater fish in freshwater ponds or underwater cages in coastal or open ocean waters. Aquaculture, the world's fastest-growing type of food production, is sometimes called the blue revolution. It involves cultivating fish in freshwater ponds, lakes, reservoirs, or rice paddies, or in underwater cages in coastal saltwater lagoons, estuaries, or offshore in deeper ocean waters. The fish are harvested when they reach marketable size.

How can we produce food more sustainably?

More sustainable food production will require using resources more efficiently, sharply decreasing the harmful environmental effects of industrialized food production, and eliminating government subsidies that promote such harmful impacts.

Three modern systems that supply most of our food:

*Uses about 40% of the world's land 1. Croplands- produce mostly grains and provides about 77% of the world's food using 11% of its area. 2. Rangelands, pastures, and feedlots- produce meat and meat products and supply about 16% of the world's food using 29% of the land area. 3. Fisheries and aquaculture- (fish farming) provide about 7% of the world's food.

Synthetic Pesticides Disadvantages

- Accelerate the development of genetic resistance to pesticides in pest organisms. - Can put farmers on a financial treadmill. - Some insecticides kill natural predators and parasites that help control the pest populations. - Pesticides do not stay put and can pollute the environment. - Harm wildlife and human health

Conservation Tillage-Farming

A method of soil cultivation that leaves the previous year's crop residue (such as corn stalks or wheat stubble) on fields before and after planting the next crop, to reduce soil erosion and runoff. **no tillage farming is supposed to be good??

Advantages of Indoor Hydroponics

- Crops can be grown indoors under controlled conditions almost anywhere - Yields and availability are increased because crops are grown year round, regardless of weather conditions - In dense urban areas, crops can be grown on rooftops, underground with artificial lighting (done in Tokyo, Japan), and on floating barges, requiring less land. - Fertilizer and water use are reduced through the recycling of nutrient and water solutions. There is no runoff of excess fertilizer into streams or other waterways. - In the controlled greenhouse environment, there is little or no need for pesticides. No soil erosion or buildup of excess mineral salts.

Alternatives to Conventional Pesticides

- Fool the pest : Examples include rotating the types of crops planted in a field each year and adjusting planting times so that major insect pests either starve or get eaten by their natural predators. - Provide homes for pest enemies - Implant genetic resistance - Bring in natural enemies - Use insect perfume : Trace amounts of sex attractants (called pheromones) can lure pests into traps or attract their natural enemies into crop fields. - Bring in hormones - Reduce the use of synthetic herbicides to control weeds

Disadvantages of IPM

- It requires expert knowledge about each pest situation and takes more time than does using conventional pesticides. - Initial costs might be higher

Animal Feedlots Disadvantages

- Large inputs of grain, fish meal, water, and fossil fuels - Greenhouse gas (CO2 and CH4) emissions - Concentration of animal wastes that can pollute water - Use of antibiotics can increase genetic resistance to microbes in humans

Plantation Agriculture

A form of industrialized agriculture used primarily in tropical, less developed countries. Involves growing cash crops, such as bananas, soybeans (mostly to feed livestock), sugarcane (to produce sugar and ethanol fuel), coffee, palm oil (used as cooking oil and to produce biodiesel fuel), and veggies on large monoculutre plantations, mostly for export to more developed countries.

Second Generation Pesticides

A major pest control revolution began in 1939, when entomologist Paul Müller discovered that the chemical DDT (dichlorodiphenyltrichloroethane) was a potent insecticide. DDT was the first of the so-called second-generation pesticides that were produced in the laboratory. It soon became the world's most-used pesticide, and Müller received the Nobel Prize in Physiology or Medicine in 1948 for his discovery. Some second-generation pesticides, however, have turned out to be hazardous as well as helpful. Since 1970, chemists have increased their use of natural repellents, poisons, and other chemicals produced by plants, generally referred to as biopesticides. They are again copying nature to improve first-generation biopesticides.

Greenhouses

A newer form of industrialized agriculture uses large arrays of greenhouses to raise crops indoors. In sunny areas, greenhouses can be used to grow crops year round and in some areas such as Iceland and parts of the western United States they are heated with geothermal energy. Water can be saved with greenhouses because the water can be distributed to the crops more efficiently. Crops can be grown in greenhouses without soil! Modern industrialized agriculture produces large amounts of food at reasonable prices. But is it sustainable? A growing number of analysts say it is not because it violates the three principles of sustainability. It relies heavily on nonrenewable fossil fuels, does not rely on a diversity of crops as a form of ecological insurance, and neglects the conservation and recycling of nutrients in topsoil.

Artificial Selection

A process in the breeding of animals and in the cultivation of plants by which the breeder chooses to perpetuate only those forms having certain desirable inheritable characteristics.

Second Green Revolution

A second green revolution has been taking place since 1967. Fast-growing dwarf varieties of rice and wheat, specially bred for tropical and subtropical climates, have been introduced into middle-income, less-developed countries such as India, China, and Brazil. Producing more food on less land has helped to protect some biodiversity by preserving large areas of forests, grasslands, wetlands, and easily eroded mountain terrain that might otherwise be used for farming.

Erosion Hotspots

An additional way to conserve the earth's topsoil is to retire the estimated one-tenth of the world's marginal cropland that is highly erodible and accounts for the majority of the world's topsoil erosion. The goal would be to identify erosion hotspots, withdraw these areas from cultivation, and plant them with grasses or trees, at least until their topsoil has been renewed.

Pest

Any species that interferes with human welfare by competing with us for food, invading lawns and gardens, destroying building materials, spreading disease, invading ecosystems, or simply being a nuisance.

3 Reasons for not using Hydroponics

First, it takes a lot of money to establish such systems although they typically are cheaper to use in the long run. Second, many growers fear that hydroponics requires substantial technical knowledge, while in reality it is very similar to traditional gardening and crop production. Third, it could threaten the profits of large and politically powerful industrialized companies that produce farming-related products such as pesticides, manufactured inorganic fertilizers, and farm equipment.

Rachel Carson (case study)

In 1958, the commonly used pesticide DDT was sprayed to control mosquitoes near the home and private bird sanctuary of one of Carson's friends. After the spraying, her friend witnessed the agonizing deaths of several birds. She begged Carson to find someone to investigate the effects of pesticides on birds and other wildlife. In 1962, she published her findings in popular form in Silent Spring, a book whose title warned of the potential silencing of "robins, catbirds, doves, jays, wrens, and scores of other bird voices" because of their exposure to pesticides. Chemical manufacturers understandably saw the book as a serious threat to their booming pesticide business, and they mounted a campaign to discredit Carson. During these intense attacks, Carson was a single mother and the sole caretaker of an aged parent. She was also suffering from terminal breast cancer. Yet she strongly defended her research and countered her critics. She died in 1964—about 18 months after the publication of Silent Spring—without knowing that many historians would consider her work to be an important contribution to the modern environmental movement then emerging in the US. Eventually led to the banning of many pesticides in the United States and other countries.

Food Security

In a country that enjoys food security, all or most of the people in the country have daily access to enough nutritious food to live active and healthy lives...however, we have unequal access to food around the world.

Case Study: Soil Erosion in the US

In the United States, a third of the country's original topsoil is gone and much of the rest is degraded. 1930s dust bowl and drought Before settlers began grazing livestock and planting crops there in the 1870s, the deep and tangled root systems of native prairie grasses anchored the fertile topsoil firmly in place. But plowing the prairie tore up these roots, and the crops that settlers planted annually in their place had less extensive root systems. After each harvest, the land was plowed and left bare for several months, exposing the topsoil to high winds. Overgrazing by livestock in some areas also destroyed large expanses of grass, denuding the ground. During May of 1934, a cloud of topsoil blown off the Great Plains traveled some 2,400 kilometers (1,500 miles) and blanketed most of the eastern United States with dust. Became known as the DUST BOWL In 1935, the United States passed the Soil Erosion Act, which established the Soil Conservation Service (SCS) as part of the USDA.

Agribusiness

In the United States, industrialized farming has evolved into agribusiness, as a small number of giant multinational corporations increasingly control the growing, processing, distribution, and sale of food in U.S. and global markets. As a result, the average U.S. farmer now feeds 129 people compared to 19 people in the 1940s.

Integrated Pest Management (IPM) Program

In this more sustainable approach, each crop and its pests are evaluated as parts of an ecological system. Then farmers develop a carefully designed control program that uses a combination of cultivation, biological, and chemical tools and techniques, applied in a coordinated process tailored to each situation. The overall aim of is to reduce crop damage to an economically tolerable level. IPM has reduced pesticide use in many countries such as Cuba, Brazil, Indonesia, Denmark, Sweden, etc.

Contour Planting

Involves plowing and planting crops in rows across the slope of the land rather than up and down. Each row acts as a small dam to help hold topsoil and to slow water runoff.

Soil Conservation

Involves using a variety of methods to reduce topsoil erosion and to restore soil fertility, mostly by keeping the land covered with vegetation.

Strip Cropping and Cover Crops

It involves planting alternating strips of a row crop (such as corn or cotton) and another crop that completely covers the soil, called a cover crop (such as alfalfa, clover, oats, or rye). The cover crop traps topsoil that erodes from the row crop and catches and reduces water runoff. Some cover crops also add nitrogen to the soil. When one crop is harvested the other crop is left to catch and reduce water runoff.

Desertification

It occurs when the productive potential of topsoil falls by 10% or more because of a combination of prolonged drought and human activities such as overgrazing and deforestation that reduce or degrade topsoil. Over thousands of years, the earth's deserts have expanded and contracted, mostly because of natural climate change. However, human use of the land, especially for agricultural purposes, has accelerated desertification in some parts of the world mostly because of deforestation, overplowing, and overgrazing.

Circle of Poison or Boomerang Effect

Laws within countries protect citizens to some extent, banned or unregistered pesticides may be manufactured in one country and exported to other countries. For example, U.S. pesticide companies make and export to other countries pesticides that have been banned or severely restricted—or never even evaluated—in the United States. Residues of some banned or unapproved chemicals exported to other countries can return to the exporting countries on imported food. The wind can also carry persistent pesticides from one country to another.

Food Insecurity

Living with chronic hunger and poor nutrition, which threatens their ability to lead healthy and productive lives. The main cause of this is poverty. Other causes though are war, upheaval, corruption, and bad weather (drought, heat waves, etc.), which interfere with food distribution and transportation systems.

Ecological Surprises: The Law of Unintended Consequences (case study)

Malaria once infected nine of every ten people in North Borneo, now known as the eastern Malaysian state of Sabah. In 1955, the WHO began spraying the island with dieldrin (a DDT relative) to kill malaria-carrying mosquitoes. The program was so successful that the dreaded disease was nearly eliminated. Insects died too--> lizards ate the dead insects and died--> cats ate the lizards and died too--> rats became a huge problem because all the cats were gone. When the people became threatened by sylvatic plague carried by rat fleas, the WHO parachuted healthy cats onto the island to help control the rats. Operation Cat Drop worked. Caterpillar overpopulation because all of its predators were gone. Ultimately, this episode ended well: both malaria and the unexpected effects of the spraying program were brought under control. Nevertheless, this chain of unintended and unforeseen events emphasizes the unpredictability of using insecticides.

Irrigation has a downside:

Most irrigation water is a dilute solution of various salts, such as sodium chloride (NaCl), that are picked up as the water flows over or through soil and rocks. Irrigation water that has not been absorbed into the topsoil evaporates, leaving behind a thin crust of dissolved mineral salts in the topsoil. Repeated applications of irrigation water in dry climates lead to the gradual accumulation of salts in the upper soil layers—a soil degradation process called salinization. It stunts crop growth, lowers cropcan eventually kill plants and ruin the land. Another problem with irrigation is waterlogging. The biggest problem resulting from excessive irrigation in agriculture is that it has contributed to depletion of groundwater and surface water supplies in many areas of the world.

Alley Cropping or Agroforestry

One or more crops, usually crops that add nitrogen to the soil, are planted together in alleys between orchard trees or fruit-bearing shrubs, which provide shade. This reduces water loss by evaporation and helps to retain and slowly release soil moisture—an insurance policy during prolonged drought. The trees also can provide fruit, and tree trimmings can be used as fuelwood, mulch, and green manure for the crops. Agroforestry is widely used in South America, South- east Asia, and sub-Saharan Africa.

Top 10 Causes of Death in America

Related to diet! diet—heart disease, stroke, Type 2 diabetes, and some forms of cancer. Treatment for illnesses stemming from obesity adds about $147 billion a year to the U.S. health-care bill. And the roughly $58 billion that Americans spend each year trying to lose weight is more than twice the $24 billion per year that the United Nations estimates is needed to eliminate undernutrition and malnutrition in the world.

Lack of Vitamins and Minerals

Most of these people live in less-developed countries. Some 250,000-500,000 children younger than age 6 go blind each year from a lack of vitamin A, and within a year, more than half of them die. Having too little iron (Fe)—a component of the hemoglobin that transports oxygen in the blood--causes anemia. It results in fatigue, makes infection more likely, and increases a woman's chances of dying from hemorrhage in childbirth. According to the WHO, one of every five people in the world—mostly women and children in less-developed countries—suffers from iron deficiency. Elemental iodine is essential for proper functioning of the thyroid gland, which produces hormones that control the body's rate of metabolism. A chronic lack of iodine can cause stunted growth, mental retardation, and goiter—a swollen thyroid gland that can lead to deafness. Almost one-third of the world's people do not get enough iodine in their food and water.

Industrialized Food Production Requires Huge Inputs of Energy

Much of the food produced today is transported across countries and between countries from producers to consumers. Example: It takes about 10 units of nonrenewable fossil fuel energy to put 1 unit of food energy on the table. This is just one reason why modern food production and consumption are dependent on oil and other fossil fuels that are projected to become more costly. Bottom line: producing, processing, transporting, and consuming industrialized food is highly dependent on fossil fuels and results in a large net energy loss.

Organic Agriculture

One component of more sustainable agriculture is organic agriculture, in which crops are grown without the use of synthetic pesticides, synthetic inorganic fertilizers, or genetically engineered seeds, and animals are grown without the use of antibiotics or synthetic growth hormones. Over 2 decades of research indicates that organic farming has a number of environmental advantages over industrialized farming. On the other hand, conventional agriculture usually can produce higher yields of crops on smaller areas of land than organic agriculture can. Another drawback is that most organically grown food costs 10-100% more than conventionally produced food (depending on specific items), primarily because organic farming is more labor intensive.

Aquaculture Can Harm Aquatic Ecosystems

One environmental problem associated with aquaculture is that using fish meal and fish oil to feed farmed fish can deplete populations of wild fish because about 37% of the wild marine fish catch goes to making fish meal and fish oil. This is also a very inefficient process. Another problem is that fish raised on fish meal or fish oil can be contaminated with long-lived toxins such as PCBs found on ocean bottoms. Fish farms, especially those that raise carnivorous fish such as salmon and tuna, also produce large amounts of wastes. Along with pesticides and antibiotics used in fish farms, these wastes can pollute aquatic ecosystems and fisheries. Yet another problem is that farmed fish can escape their pens and mix with wild fish, changing and possibly disrupting the gene pools of wild populations. Similarly, aquaculture can end up promoting the spread of invasive plant species. An Asian kelp called wakame or undaria is a popular food product raised on some farms. But this invasive seaweed is disrupting coastal aquatic systems in several parts of the world.

Slash-and-Burn Agriculture

One type of polyculture. This type of subsistence agriculture involves burning and clearing small plots in tropical forests, growing a variety of crops for a few years until the soil is depleted of nutrients, and then shifting to other plots to begin the process again. Early users of this method learned that each abandoned patch normally had to be left fallow (unplanted) for 10-30 years before the soil became fertile enough to grow crops again. Slash-and-burn polyculture lessens the need for fertilizer and water, because root systems at different depths in the soil capture nutrients and moisture efficiently, and ashes from the burning provide soil nutrients. Insecticides and herbicides are rarely needed because multiple habitats are created for natural predators of crop-eating insects, and weeds have trouble density of crop plants.

Broad-Spectrum Agents

Pesticides that are toxic to many pests, but also to beneficial species. Examples are chlorinated hydrocarbon compounds such as DDT and organophosphate compounds such as malathion and parathion.

Natural Enemies

Predators, parasites, and disease organisms who control the populations of most potential pest species as part of the earth's natural capital. For example, the world's 30,000 known species of spiders, including the wolf spider, kill far more insects every year than humans do by using chemicals.

Organic Fertilizers

The second best way to maintain soil fertility is to use organic fertilizers from animal and plant materials or use manufactured inorganic fertilizers produced from various minerals, which are mined from the earth's crust.

Yield

The amount of food produced per unit of land.

The industrialization of food production has been made possible by...

The availability of energy, mostly from nonrenewable oil and natural gas. It is used to run farm machinery, irrigate crops, and produce pesticides (mostly from petrochemicals produced when oil is refined) and commercial inorganic fertilizers. Fossil fuels are also used to process food and transport it long distances within and between countries.

Percistance

The length of time pesticides remain deadly in the environment. Some, such as DDT and related compounds, remain in the environment for years and can be biologically magnified in food chains and webs. Others, such as organophosphates, are active for days or weeks and are not biologically magnified but can be highly toxic to humans.

Soil Erosion

The movement of soil components, especially surface litter and topsoil, from one place to another by the actions of wind and water. Some erosion of topsoil is natural, and some is caused by human activities. Erosion of topsoil has two major harmful effects. One is loss of soil fertility through depletion of plant nutrients in topsoil. The other is water pollution in nearby surface waters, where eroded topsoil ends up as sediment. This can kill fish and shellfish and clog irrigation ditches, boat channels, reservoirs, and lakes. Additional water pollution occurs when the eroded sediment contains pesticide residues. By removing vital plant nutrients from topsoil and adding excess plant nutrients to aquatic systems, we degrade the topsoil and pollute the water, and thus alter the carbon, nitrogen, and phosphorus cycles. In other words, we are violating part of the earth's chemical cycling principle of sustainability.

O and A Horizons

The roots of most plants and the majority of a soil's organic matter are concentrated in the soil's two upper layers, the O horizon of leaf litter and the A horizon of topsoil. In most mature soils, these two layers teem with bacteria, fungi, earthworms, and small insects, all interacting in complex ways. Bacteria and other decomposer microorganisms, found by the billions in every handful of topsoil, break down some of the soil's complex organic compounds into a porous mixture of the partially decomposed bodies of dead plants and animals, called humus, and inorganic materials such as clay, silt, and sand. Soil moisture carrying these dissolved nutrients is drawn up by the roots of plants and transported through stems and into leaves as part of the earth's chemical cycling processes. As long as the O and A horizons are anchored by vegetation, the soil layers as a whole act as a sponge, storing water and nutrients, and releasing them in a nourishing trickle.

Agrobiodiversity

The world's genetic variety of animal and plant species used to provide food. For example, India once planted 30,000 varieties of rice. Now more than 75% of its rice production comes from only ten varieties and soon, almost all of its production may come from just one or two varieties. In the United States, this tradition is disappearing as more farmers plant seeds for genetically engineered crops. Companies selling these seeds have patents on them, forbid users to save them, and have prosecuted a number of farmers (Food Inc. Video). Failure to preserve agrobiodiversity as an ecological insurance policy is a serious violation of the biodiversity principle of sustainability.

Organic Labels

There are major differences between conventional industrialized agriculture and organic agriculture. In the United States, a label of 100 percent organic means that a product is raised only by organic methods and contains all organic ingredients. Products labeled organic must contain at least 95% organic ingredients. In addition, products labeled made with organic ingredients must contain at least 70% organic ingredients but cannot display the U.S. Department of Agriculture Organic seal on their packages.

Industrialized Agriculture or High-Input Agriculture

Uses heavy equipment and large amounts of financial capital, fossil fuels, water, commercial inorganic fertilizers, and pesticides to produce single crops, or monocultures. The major goal of this is to steadily increase each crop's yield.

How is food produced?

We have used high-input industrialized agriculture and lower-input traditional methods to greatly increase supplies of food.

There Are Limits to Expansion of the Green Revolutions

Without huge inputs of inorganic fertilizer, pesticides, and water, most green revolution and genetically engineered crop varieties produce yields that are no higher (and are sometimes lower) than those from traditional strains. And these high-inputs cost too much for most subsistence farmers in less-developed countries.


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