please see files below to help with this assignment. APA style, cite work from book that was provided,
Compose a 300-word (minimum) essay on the topic below. Essays must be double-spaced and use APA-style in-text citations to reference ideas or quotes that are not your own. You must include a separate bibliography.
What would happen to the economy and our buying habits if the hidden mineral extraction costs associated with environmental damage due to mining, processing, use, and disposal were included in the market prices paid by consumers for products containing those minerals?
How would it change the way mining companies and manufacturers did business?
Could that help to create a more sustainable society? Explain.
You should cite and quote from assigned readings, AVP’s, videos, and module activities to support the ideas in your essay.
12ch,13 14 most of the essay stuff comes from CH14
Compose a 300
–
word (minimum) essay on the topic below. Essays must be double
–
spaced and use APA
–
style in
–
text citations to reference ideas or quotes that are not your own. You must include a separate
bibliography.
What would happen to the economy and our buying habits if the hidden mineral extraction costs
associated with environmental damage due to mining, processing, use, and disposal were included in
the market prices paid by consumers for products containing tho
se minerals?
How would it change the way mining companies and manufacturers did business?
Could that help to create a more sustainable society? Explain.
You should cite and quote from assigned readings, AVP’s, videos, and module activities to s
upport the
ideas in your essay.
12
ch,13 14
most of the essay stuff comes from CH14
Compose a 300-word (minimum) essay on the topic below. Essays must be double-spaced and use APA-
style in-text citations to reference ideas or quotes that are not your own. You must include a separate
bibliography.
What would happen to the economy and our buying habits if the hidden mineral extraction costs
associated with environmental damage due to mining, processing, use, and disposal were included in
the market prices paid by consumers for products containing those minerals?
How would it change the way mining companies and manufacturers did business?
Could that help to create a more sustainable society? Explain.
You should cite and quote from assigned readings, AVP’s, videos, and module activities to support the
ideas in your essay.
12ch,13 14 most of the essay stuff comes from CH14
G. Tyler Miller, Scott E. Spoolman
Living in the Environment
20th Edition
12.1aFood Security and Food Insecurity
Food security
is the condition under which people have access to enough safe and nutritious food for a healthy and active lifestyle. More than 1 billion people work in agriculture to produce food on about 38% of the earth’s ice-free land. They produce more than enough food to meet the basic nutritional needs of every person on the earth. Despite this food surplus, one of every nine people in the world—about 815 million in all—is not getting enough to eat. These people face
food insecurity
by having to live with chronic hunger and poor nutrition that threaten their ability to lead healthy and active lifestyles. About 98% of the people facing food insecurity live in less developed countries, and 60% of them are women. In the United States, about 41 million people (13 million of them children under age 5) faced food insecurity in 2017.
Each day, there are about 249,000 more people at the world’s dinner tables and many of them will have little or no food on their plates. By 2050, there will likely be at least 2.3 billion more people to feed. Most of these newcomers will be born in the major cities of less-developed countries. A critical question is how will we feed the projected 9.9 billion people in 2050 without causing serious harm to the environment? We explore possible answers to this question throughout this chapter.
12.1bChronic Hunger and Malnutrition
To maintain good health and resist disease, individuals need large amounts of macronutrients (such as carbohydrates, proteins, and fats) and smaller amounts of micronutrients—vitamins, such as A, B, C, and E, and minerals, such as iron, iodine, and calcium.
People who cannot grow or buy enough food to meet their basic energy needs suffer from
chronic undernutrition
, or
hunger
, a condition in which they do not get enough protein and key vitamins and minerals. This can weaken them, make them more vulnerable to disease, hinder the normal physical and mental development of children, and threaten their ability to lead healthy and productive lives. Most of the world’s hungry people can afford only a low-protein, high-carbohydrate, vegetarian diet consisting mostly of grains such as wheat, rice, and corn. In other words, they live low on the food chain (
).
Figure 12.2
The poor cannot afford to eat meat and, in order to survive, eat further down the food chain on a diet of grain.
Perhaps the worst form of food shortage is
famine
, which occurs when there is a severe shortage of food in an area. This can result in mass starvation, many deaths, economic chaos, and social disruption. Famines are usually caused by crop failures from drought, flooding, war, and other catastrophic events.
In more-developed countries, many people have a diet that is heavy on cheap food loaded with fats, sugar, and salt. These individuals often suffer from
chronic malnutrition
, a condition in which they do not get enough protein and other key nutrients. This can weaken them, make them more vulnerable to disease, and hinder the normal physical and mental development of children.
According to the United Nations Food and Agriculture Organization (FAO), in 2018 there were about 815 million chronically undernourished and malnourished people in the world (
). According to the FAO, at least 3.1 million children younger than age 5 died from chronic hunger and malnutrition in 2015 (the latest year for which data are available). Globally, the number and percentage of people suffering from chronic hunger has been declining since 1992 (
) but there is still a long way to go. In some areas of the world, the news is not so good. One of every four people living south of the Sahara Desert (sub-Saharan Africa) is undernourished.
Figure 12.3
One of every three children younger than age 5 in less-developed countries, such as this starving child in Bangladesh, suffers from severe malnutrition caused by a lack of calories and protein.
Rowan Gillson/Design Pics/Superstock
Figure 12.4
The number and percentage of people in less-developed countries that suffer from undernutrition and hunger have each been declining.
(Compiled by the authors using data from U.S. Department of Agriculture, UN Food and Agriculture Organization, and Earth Policy Institute.
12.1cLack of Vitamins and Minerals
About 2 billion people, most of them in less-developed countries, suffer from a deficiency of one or more vitamins and minerals, usually vitamin A, iron, and iodine. According to the World Health Organization (WHO), at least 250,000 children younger than age 6, most of them in less-developed countries, go blind every year from a lack of vitamin A. Within a year, more than half of them die. Providing children with adequate vitamin A could save at least 130,000 lives per year.
Having too little iron (Fe) in the blood is a condition called anemia. It causes fatigue, makes infection more likely, and increases a woman’s chances of dying from hemorrhage in childbirth. According to the WHO, about 30% the world’s people—most of them women and children in less-developed countries—suffer from iron deficiency. By 2050, iron deficiency could affect the health of 1.4 billion people.
The chemical element iodine (I) is essential for proper functioning of the thyroid gland, which produces hormones that control the body’s rate of metabolism. Chronic lack of iodine can cause stunted growth, mental retardation, and goiter—a severely swollen thyroid gland that can lead to deafness (
). According to the United Nations (UN), some 600 million people (almost twice the current U.S. population) suffer from goiter, most of them in less-developed countries. Every year, 19 million babies are at risk of permanent brain damage due to a lack of iodine in pregnancy and early childhood, according to a 2018 UN report. The FAO and the WHO estimate that eliminating this serious health problem by adding traces of iodine to salt would cost the equivalent of only 2 to 3 cents per year for every person in the world.
Figure 12.5
This woman suffers from goiter, an enlargement of the thyroid gland, caused by a lack of iodine in her diet.
Mike Goldwater/Alamy Stock Photo
12.1dHealth Problems from Too Much Food
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 those who are overfed and overweight face similar health problems: lower life expectancy, greater susceptibility to disease and illness, and lower productivity and life quality
In order, the countries with the most overweight and obese people are the United States, China, India, Russia, and Brazil. According to a study by the McKinsey Global Institute, the resulting healthcare and lost-productivity costs are about $2 trillion a year—more than the combined annual global costs of war, terrorism, and armed violence.
72%
Percentage of U.S. adults over age 20 who are obese (38%) or overweight (34%)
According to the U.S. Centers for Disease Control and Prevention (CDC), about 72% of adults over age 20 and 33% of all children in the United States are overweight or obese (Figure 12.6). A study by Columbia University and the Robert Wood Johnson Foundation found that obesity plays an important role in nearly one in five deaths in the United States from heart disease, stroke, type 2 diabetes, and some forms of cancer.
Figure 12.6
Almost 3 of every 4 adults over age 20 in the United States are overweight or obese.
These three systems depend on a small number of plant and animal species. Of the estimated 50,000 plant species that people can eat, about 90% of the world’s food calories come from only 14 of them. At least half the world’s people survive primarily by eating rice, wheat, and corn because they cannot afford meat. Only a few species of mammals and fish provide most of the world’s meat and seafood.
Such food specialization puts us in a vulnerable position. If any of the small number of crop strains, livestock breeds, and fish and shellfish species that we depend on were to become depleted, the consequences would be dire. Plant or livestock diseases, environmental degradation, and climate change could cause such depletion. This food specialization violates the biodiversity principle of sustainability, which calls for depending on a variety of food sources as an ecological insurance policy against changing environmental conditions.
Despite such genetic vulnerability, since 1960, there has been a staggering increase in global food production from all three of the major food production systems. Three major technological advances have been especially important:
1. the development of
irrigation
, a mix of methods by which water is supplied to crops by artificial means;
2.
synthetic fertilizers
—manufactured chemicals that contain nutrients such as nitrogen, phosphorus, potassium, calcium, and several others; and
3.
synthetic pesticides
—chemicals manufactured to kill or control populations of organisms that interfere with crop production.
4. 12.2bIndustrialized Agriculture
5.
Industrialized agriculture
, or
high-input agriculture
, uses motorized equipment (see
) along with large amounts of financial capital, fossil fuels, water, commercial inorganic fertilizers, and pesticides. Industrialized agriculture produces a single crop at a time on a plot of land, a practice known as
monoculture
(
). The major goal of industrialized agriculture is to increase each crop’s
yield
—the amount of food produced per unit of land. Industrialized agriculture is practiced on 25% of all cropland, mostly in more-developed countries, and produces about 80% of the world’s food.
6. Figure 12.7
7. Monoculture soybean field.
8.
9. Oticki/
Plantation agriculture is a form of industrialized agriculture used primarily in less-developed tropical countries. It involves growing cash crops such as bananas, coffee, vegetables, soybeans (mostly to feed livestock; see
), sugarcane (to produce sugar and ethanol fuel), and palm oil (to produce cooking oil and biodiesel fuel). These crops are grown on large monoculture plantations, mostly for export to more-developed countries12.2cTraditional Agriculture
Traditional, low-input agriculture provides about 20% of the world’s food crops on about 75% of its cultivated land, mostly in less-developed countries. It takes two basic forms.
Traditional subsistence agriculture
combines 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. In
traditional intensive agriculture
, farmers try to obtain higher crop yields by increasing their inputs of human and draft animal labor, animal manure for fertilizer, and water. With good weather, farmers can produce enough food to feed their families and have some left over to sell for income.
Figure 12.8
Traditional subsistence agriculture in India.
Some traditional farmers focus on cultivating a single crop, but many grow several crops on the same plot simultaneously, a practice known as
polyculture
. This method relies on solar energy and natural fertilizers such as animal manure. The various crops mature at different times. This provides food year-round and keeps the topsoil covered to reduce erosion from wind and water. Polyculture also lessens the need for fertilizer and water because root systems at different depths in the soil capture nutrients and moisture efficiently. In addition, weeds have trouble competing with the multitude and density of crop plants, and this crop diversity reduces the chance of losing most or all of the year’s food supply to pests, bad weather, and other misfortunes.
One type of polyculture is known as slash-and-burn agriculture (
). 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. In parts of South America and Africa, some traditional farmers grow as many as 20 different crops together on small cleared plots.
Figure 12.9
Poor settlers in Peru have cleared and burned this small plot in a tropical rain forest in the Amazon and planted it with seedlings to grow food for their survival.
Polyculture is an application of the biodiversity principle of sustainability. Crop diversity helps protect and replenish the soil and reduces the chance of losing most or all of the year’s food supply to pests, bad weather, and other misfortunes. Research shows that, on average, low-input polyculture produces higher average yields than high-input industrialized monoculture, while using less energy and fewer resources, and provides more food security for small landowners. For example, ecologists Peter Reich and David Tilman found that carefully controlled polyculture plots with 16 different species of plants consistently out-produced plots with 9, 4, or only 1 type of plant species.
Learning from Nature
Scientists are studying natural biodiversity to learn how to grow crops using polyculture. The idea is to grow stable crop systems, less vulnerable to environmental threats than monoculture crops are, and to increase yields.
10.
11. 12.2dOrganic Agriculture
12. A fast-growing sector of U.S. and world food production is
organic agriculture
. Organic crops are grown without the use of synthetic pesticides, synthetic inorganic fertilizers, or genetically engineered seed varieties. Animals are raised on 100% organic feed without the use of antibiotics or growth hormones. Organic food sales have more than tripled since 2000.
13. In the United States, by law, a label of 100 percent organic (or USDA Certified Organic) means that a product is produced only by organic methods and contains all organic ingredients. Products labeled “organic” must contain at least 95% organic ingredients. Those labeled made with organic ingredients must contain at least 70% organic ingredients. The word natural has no requirement for organic ingredients. In 2018, 7% of the fruit, 11% of the vegetables, 15% of the frozen fruit, and 5% of the frozen vegetables sold in the United States were organic. In 2018, the U.S. Department of Agriculture (USDA) called the U.S. food supply “among the safest in the world” with more than 99% of the samples tested having pesticide residues well below the levels established by the EPA.
compares organic agriculture with industrialized agriculture.
14. Figure 12.10
15. Major differences between industrialized agriculture and organic agriculture.
16.
17.
18.
Left top: B Brown/ . Left center: ZoranOrcik/ . Left bottom: Art Konovalov/ . Right top: Noam Armonn/ . Right center: Varina C/ and Jay Patel/ . Right bottom: Adisa/ .
12.2eGreen Revolutions Have Increased Crop Yields
Farmers have two ways to produce more food: farm more land or increase yields from existing cropland. Since 1950, most of the dramatic increase in global grain production has been the result of increasing crop yields through industrialized agriculture.
This process, called the
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, synthetic inorganic fertilizers, and pesticides. Third, increase the number of crops grown per year on a plot of land.
In the first green revolution, which occurred between 1950 and 1970, this high-input approach dramatically raised crop yields in most of the world’s more-developed countries, especially the United States (see the Case Study that follows).
In the second green revolution, which began in 1967, fast-growing varieties of rice and wheat, specially bred for tropical and subtropical climates, were introduced into middle-income, less-developed countries such as India, China, and Brazil. Producing more food on less land in such countries has helped protect biodiversity by preserving large areas of forests, grasslands, and wetlands that might otherwise be used for farming.
Largely because of the two green revolutions, between 1950 and 2018, world grain production (Figure 12.11, left) and per capita grain production (Figure 12.11, right) grew dramatically. In 2018, the world’s five largest grain-producing countries—the United States, China, the European Union, Brazil, and India—produced two-thirds of the world’s grains. However, according to the U.S. Department of Agriculture (USDA), the global rate of growth in grain crop yields has slowed from an average of 2.2% per decade before 1990 to 1.2% per decade since then.
Figure 12.11
Growth in worldwide grain production (left) of wheat, corn, and rice, and in per capita grain production (right) between 1950 and 2018.
Critical Thinking:
1. Why do you think grain production per capita has grown less consistently than total grain production?
(Compiled by the authors using data from U.S. Department of Agriculture, Worldwatch Institute, UN Food and Agriculture Organization, and Earth Policy Institute.)
People directly consume about half of the world’s grain production. Most of the rest is fed to livestock and is consumed by people who can afford to eat meat and meat products.
China faces the daunting challenge of how to feed 18% of the world’s population with less than 10% of the world’s cropland. A growing percent of its population is affluent enough to eat meat. To help feed its people Chinese companies are buying land and food companies in other countries such as the United States, Ukraine, Chile, and Tanzania.
An important factor in expanded industrialized crop production has been the use of
farm subsidies
, or government payments and tax breaks intended to help farmers stay in business and increase their yields. In the United States, most subsidies go to corporate farming operations for raising corn, wheat, soybeans, and cotton on an industrial scale. U.S. government records show that in recent years, nearly 74% of all subsidies went to just 10% of all U.S. farmers.
Case Study
Industrialized Food Production in the United States
In the United States, industrialized farming has evolved into agribusinesses. A few giant multinational corporations increasingly control the growing, processing, distribution, and sale of food in U.S. and global markets. In total annual sales, agriculture is bigger than the country’s automotive, steel, and housing industries combined. Because of advances in technology, the numbers of U.S. farms and farmers have dropped sharply as production has risen. As a result, the average U.S. farmer now feeds 129 people compared to 19 people in the 1940s.
1%
Percentage of the U.S. workforce who are farmers—down from 18% in 1910
Because of the efficiency of U.S. agriculture, Americans spend the lowest percentage of disposable income in the world—an average of 10% on food. By contrast, low-income people in less-developed countries typically spend 50–70% of their income on food, according to the USDA and FAO.
However, because of a number of hidden costs related to food production and consumption, most American consumers are unaware that their actual food costs are much higher than the market prices they pay. Such hidden costs include the costs of pollution and environmental degradation, higher health insurance bills related to the harmful health effects of industrialized agriculture, and government farm subsidies.
12.2fGenetic Revolutions: Crossbreeding and Genetic Engineering
For centuries, farmers and scientists have used crossbreeding to develop genetically improved varieties of crops and livestock animals. Through artificial selection, farmers have developed genetically improved varieties of crops (see
) and livestock animals. For example, a tasty but small species of tomato might be crossbred with a larger species of tomato to produce a larger, tasty tomato species. Such selective breeding in this first gene revolution has yielded amazing results. For example, ancient ears of corn were about the size of your little finger, and wild tomatoes were once the size of grapes, but most of the large varieties used now were selectively bred.
Traditional crossbreeding is a slow process. It often takes 15 years or more to produce a commercially valuable new crop variety and it can combine traits only from species that are genetically similar. Typically, resulting varieties remain useful for only 5 to 10 years before pests and diseases reduce their yields. However, important advances are still being made with this method.
Today, a second gene revolution is taking place. Scientists and engineers are using genetic engineering to develop genetically modified (GM) strains of crops and livestock animals. They use a process called gene splicing to add, delete, or change segments of an organism’s DNA (see
). The goal of this process is to add desirable traits or eliminate undesirable ones by transferring genes between species that would not normally interbreed in nature. The resulting organisms are called genetically modified organisms (GMOs).
Developing a new crop variety through genetic engineering takes about half as long as traditional crossbreeding and usually costs less. According to the U.S. Department of Agriculture (USDA), at least 80% of the food products on U.S. supermarket shelves contain some form of genetically modified food or ingredients and that percentage is growing.
80%
Percentage of food products sold in the United States that contain some form of genetically modified food or ingredients
A new generation of genetically altered crops is based on snipping or editing existing genes at precise locations instead of transferring genes between species. The new CRISPR gene-editing technique allows scientists to achieve desired effects by altering a plant’s own DNA without inserting new genes. Crops that are genetically engineered in this way can be brought to the market faster and more cheaply than traditionally genetically engineered crops.
12.2gGrowing Meat Consumption
Meat and animal products such as eggs and milk are sources of high-quality protein and represent the world’s second major food-producing system. According to the FAO, global meat production grew more than six-fold between 1950 and 2018. Since 1974, total global meat consumption has more than doubled according to the FAO and is likely to more than double again by 2050 as incomes rise and millions of people in rapidly developing countries consume more meat and meat products.
About half of the world’s meat comes from livestock grazing on grass in unfenced rangelands and enclosed pastures. The other half is produced through an industrialized factory farm system. This involves raising large numbers of animals bred to gain weight quickly, mostly in feedlots (
) or in crowded pens and cages in huge buildings. These operations are called concentrated animal feeding operations (CAFOs), or factory farms (
). In CAFOs, the animals are fed grain, soybeans, fishmeal, or fish oil, and some of this feed is doctored with growth hormones and antibiotics to accelerate livestock growth. Because of the crowding and runoff of animal wastes from CAFOs, these operations have harmful impacts on the air and water, which we examine later in this chapter.
Figure 12.12
Industrialized beef production: On this cattle feedlot in Arizona, thousands of cattle are fattened on grain for a few months before being slaughtered.
PETE MCBRIDE/National Geographic Creative/National Geographic Image Collection
Figure 12.13
Concentrated chicken feeding operation in Iowa (USA). Such operations can house up to 100,000 chickens.
Scott Sinklier/AgStock Images/Terra/Corbis
As a country’s income grows, more of its people tend to eat more meat, much of it produced by feeding grain to livestock. The resulting increased demand for grain, often accompanied by a loss of cropland to urban development, can lead to greater reliance on grain imports. China and India are following this trend as they become more industrialized and urbanized.
12.2hFish and Shellfish Production
The world’s third major food-producing system consists of fisheries and aquaculture. A fishery is a concentration of a particular aquatic species suitable for commercial harvesting in a given ocean area or inland body of water. Industrial fishing fleets use a variety of methods (Figure 11.8) to harvest most of the world’s marine catch of wild fish. Fish and shellfish are also produced through
aquaculture
or
fish farming
(Figure 12.14). It involves raising fish in freshwater ponds, lakes, reservoirs, and rice paddies, and in underwater cages in coastal and deeper ocean waters.
Figure 12.14
Aquaculture: Shrimp farms on the southern coast of Thailand.
Aquaculture is the world’s fastest growing type of food production. Between 1950 and 2016, global seafood production of wild and farmed fish increased more than ninefold, while the global wild catch leveled off and declined. In 2016, aquaculture accounted for 47% of the world’s fish and shellfish production (compared to 26% in 2000), and the rest were caught mostly by industrial fishing fleets (Figure 12.15). According to the Woods Hole Fisheries Service, about 90% of the world’s commercial ocean fisheries are being harvested at full capacity (61%) or are overfished (29%).
Figure 12.15
World seafood production, including both wild catch (marine and inland) and aquaculture, grew between 1950 and 2015, with the wild catch generally leveling off since 1996 and aquaculture production rising sharply since 1990.
Data Analysis:
1. In about what year did aquaculture surpass the 1980 wild catch?
(Compiled by the authors using data from UN Food and Agriculture Organization, Worldwatch Institute, and Earth Policy Institute.)
90%
Percentage of the world’s ocean fisheries that are overfished or harvested at full capacity
12.3a
Energy Use in Industrialized Food Production
The industrialization of food production and increased crop yields have been made possible by use of fossil fuels—mostly oil and natural gas—to run farm machinery and fishing vessels, to pump irrigation water for crops, and to produce synthetic pesticides and synthetic inorganic fertilizers. Fossil fuels are also used to process food and transport it long distances within and between countries. Altogether, food production accounts for about 17% of all of the energy used in the United States, more than any other industry. Burning such large quantities of fossil fuels pollutes the …
G. Tyler Miller, Scott E. Spoolman
Living in the Environment
20th Edition
· The Colorado River flows 2,300 kilometers (1,400 miles) through seven states to the Gulf of California (
). Most of its water comes from snowmelt in the Rocky Mountains. During the past 100 years, this once free-flowing river has been tamed by a gigantic plumbing system consisting of 14 major dams and reservoirs (see
) and canals that carry water to farmers, ranchers, industries, and cities.
· Figure 13.1
· The Colorado River basin: The area drained by this river system is more than one-twelfth of the land area of the lower 48 states. This map shows 6 of the river’s 14 dams. The chapter-opening photo shows the Hoover Dam and the Lake Mead reservoir on the Arizona-Nevada border.
·
·
· This system of dams and reservoirs provides electricity from its hydroelectric plants to roughly 40 million people in seven states—about one of every eight people in the United States. The river’s water is used to produce about 15% of the nation’s crops and 13% of its livestock.
· The system supplies water to some of the nation’s driest and hottest cities such as Las Vegas, Nevada, Phoenix, Arizona, and San Diego and Los Angeles, California. Take away the Colorado River’s dam-and-reservoir system, and these cities would become largely uninhabitable desert areas and California’s Imperial Valley would cease producing half of the country’s fruits and vegetables.
· So much water is withdrawn from the Colorado River to grow crops and support cities in a desert-like climate that since 1960, the river has run dry most years before reaching the Pacific Ocean. Since 1999, the river’s watershed has experienced severe
drought
, a prolonged period in which precipitation is lower than normal and evaporation is higher than normal. As a result, the water level in Lake Mead, the largest reservoir in the United States (see
) has been dropping. Climate change is expected to further reduce the river’s flow throughout the remainder of this century
· This overuse of the Colorado River illustrates the challenges faced by governments and people living in arid and semiarid regions with shared river systems. In such areas, increasing population, economic growth, crop irrigation, and climate change are putting increasing demands on limited or decreasing supplies of surface water.
· To many analysts, emerging shortages of water for drinking and irrigation in several parts of the world represent one of the major environmental challenges of this century. In this chapter, we look at where the enormous amount of freshwater that we use comes from, how we can increase the supply of freshwater, how we can use freshwater more sustainably, and how we can reduce the threat of flooding.
· 13.1aWe Are Managing Freshwater Poorly
· Water is an amazing chemical with unique properties that help to keep us and other species alive (see
). You could survive for several weeks without food, but only a few days without
freshwater
, or water that contains very low levels of dissolved salts. Water supports the earth’s life and our economies and there is no substitute for this vital form of natural capital. As water expert Sandra Postel puts it, “Water’s gift is life.”
· It takes huge amounts of water to supply food and most of the other things that we use to meet our daily needs and wants. Water also plays a key role in determining the earth’s climates and in removing and diluting some of the pollutants and wastes that we produce. Over eons, water has also sculpted the planet’s surfaces, creating valleys, canyons, and other land features
· Despite its importance, freshwater is one of our most poorly managed resources. We waste it, pollute it, and do not value it highly enough. As a result, it is available at too low a cost to billions of consumers, and this encourages waste and pollution of this resource, for which we have no substitute
· Access to freshwater is a global health issue. The World Health Organization (WHO) has estimated that each year more than 3.4 million die from waterborne infectious diseases—an average of 9,300 deaths each day because they lack access to safe drinking water.
· Access to freshwater is also an economic issue because water is vital for producing food and energy and for reducing poverty. According to the WHO, just 57% of the world’s people have water piped to their homes. The rest have to find and carry it from distant sources or wells. This daily task usually falls to women (
), who spend several hours a day collecting freshwater.
· Figure 13.2
· Each day these women carry water to their village in a dry area of India.
·
·
· SHIVJI JOSHI/National Geographic Image Collection
Finally, water is an environmental issue. Excessive withdrawal of freshwater from rivers and aquifers has resulted in falling water tables, dwindling river flows (
), shrinking lakes, and disappearing wetlands. This, in combination with water pollution in many areas of the world, has degraded water quality. It has also reduced fish populations, hastened the extinction of some aquatic species, and degraded aquatic ecosystem services. 13.1bMost of the Earth’s Freshwater Is Not Available to Us
Only 0.024% of the planet’s enormous water supply is readily available to us as liquid freshwater. This water is found in accessible underground deposits and in lakes, rivers, and streams. The rest of the earth’s water is in the salty oceans (about 96.5% of the earth’s volume of liquid water), in frozen polar ice caps and glaciers (1.7%), and underground in deep aquifers (1.7%).
0.024%
Percentage of the earth’s freshwater available to us
Fortunately, the world’s freshwater supply is continually recycled, purified, and distributed in the earth’s hydrologic cycle (see
). However, this vital ecosystem service begins to fail when we overload it with water pollutants or withdraw freshwater from underground and surface water supplies faster than natural processes replenish it.
Research indicates that atmospheric warming is altering the water cycle by evaporating more water into the atmosphere. As a result, wet places will get wetter with more frequent and heavier flooding from more rainfall and dry places will get drier with more intense drought.
We have paid little attention to our effects on the water cycle mostly because we think of the earth’s freshwater as a free and infinite resource. As a result, we have placed little or no economic value on the irreplaceable ecosystem services that water provides, a serious violation of the full-cost pricing principle of sustainability.
On a global basis, there is plenty of freshwater, but it is not distributed evenly. Differences in average annual precipitation and economic resources divide the world’s countries and people into water haves and have-nots. For example, Canada, with only 0.5% of the world’s population, has 20% of its liquid freshwater, while China, with 18% of the world’s people, has only 6.5% of the supply.
· 13.1c
· Groundwater and Surface Water
· Much of the earth’s water is stored underground. Some precipitation soaks into the ground and sinks downward through spaces in soil, gravel, and rock until an impenetrable layer of rock or clay stops it. The freshwater in these underground spaces is called groundwater—a key component of the earth’s natural capital (Figure 13.3).
·
· Figure 13.3
· Natural capital: Much of the water that falls in precipitation seeps into the ground to become groundwater, stored in aquifers.
·
· An illustration shows a three-dimensional surface, where a lake is shown and labeled. Several streams arising from the lakes are shown and labeled. Vegetation is found around the streams. Clouds are shown above the surface and water precipitates and falls from it and it is labeled as, “precipitation.” Evaporation and Transpiration and separately another Evaporation are indicated as arrow marks pointing upwards. Below the vegetation on the ground level is the water table and infiltration is indicated by downward arrow marks from the water table to the unconfined aquifer (a layer of water) which is located below the water table and confined aquifer is a layer of water below the unconfined aquifer. The layer of soil between the unconfined and confined aquifer is the less permeable material such as clay. Below the confined aquifer is the layer which is confining impermeable rock layer. Run-off is also labelled in the vegetation. The drinking water well is dug until the unconfined aquifer layer and the artesian well is dug until the confined aquifer layer.Enlarge Image
· The spaces in soil and rock close to the earth’s surface hold little moisture. However, below a certain depth, in the zone of saturation, these spaces are completely filled with freshwater. The top of this groundwater zone is the water table. The water table rises in wet weather. It falls in dry weather or when we remove groundwater from this zone faster than nature can replenish it.
·
· Deeper down are geological layers called aquifers, caverns and porous layers of sand, gravel or rock through which groundwater flows. Some aquifers contain caverns with rivers of groundwater flowing through them. Most aquifers are like large, elongated sponges through which groundwater seeps—typically moving only a meter or so (about 3 feet) per year and rarely more than 0.3 meter (1 foot) per day. Watertight (impermeable) layers of rock or clay below such aquifers keep the freshwater from escaping deeper into the earth. We use pumps to bring this groundwater to the surface for irrigating crops, supplying households, and meeting the needs of industries.
·
· Most aquifers are replenished, or recharged, naturally by precipitation that sinks downward through exposed soil and rock. Others are recharged from the side from nearby lakes, rivers, and streams.
·
· According to the U.S. Geological Survey (USGS), groundwater makes up 95% of the freshwater available to us and other forms of life. However, most aquifers recharge slowly and in urban areas so much of the landscape has been built on or paved over that freshwater can no longer penetrate the ground to recharge aquifers. In dry areas of the world, there is little precipitation available to recharge aquifers. Aquifers lying beneath the recharge zone are called deep aquifers. They either cannot be recharged or take thousands of years to recharge. On a human timescale, deep aquifers are nonrenewable deposits of freshwater.
·
· Another crucial resource is surface water, the freshwater from rain and melted snow that flows or is stored in lakes, reservoirs, wetlands, streams, and rivers. Precipitation that does not soak into the ground or return to the atmosphere by evaporation is called surface runoff. The land from which surface runoff drains into a particular stream, lake, wetland, or other body of water is called its watershed, or drainage basin. The drainage basin for the Colorado River is shown in yellow and green on the map in Figure 13.1 (Core Case Study).
·
· Connections
· Groundwater and Surface Water
There is usually a connection between surface water and groundwater because much groundwater flows into rivers, lakes, estuaries, and wetlands. Thus, if we remove groundwater in a particular location faster than it is replenished, nearby streams, lakes, and wetlands can dry up. This process degrades aquatic biodiversity and other ecosystem services. 13.1dWater Use Is Increasing
According to hydrologists, scientists who study water and its properties and movement, two-thirds of the annual surface runoff of freshwater into rivers and streams is lost in seasonal floods and is not available for human use. The remaining one-third is
reliable surface runoff
—defined as the portion of runoff that is regarded as a stable source of freshwater from year to year. GREEN CAREER: Hydrologist
Worldwide, we use 70% of the freshwater we withdraw each year from rivers, lakes, and aquifers to irrigate cropland and raise livestock. In arid regions, up to 90% of the regional water supply is used for food production. Industry uses roughly another 20% of the water withdrawn globally each year. Cities and residences use the remaining 10%.
Your
water footprint
is a rough measure of the volume of freshwater that you use directly or indirectly. Your daily water footprint includes the freshwater you use directly (for example, to drink, bathe, or flush a toilet) and the water you use indirectly through the food, energy, and products you consume. (See the Case Study that follows for information on U.S. water use.) The three largest water footprints in the world belong to India, the United States, and China, in that order.
Case Study
Freshwater Resources in the United States
According to the U.S. Geological Survey (USGS), the major uses of groundwater and surface freshwater in the United States are the cooling of electric power plants, irrigation, public water supplies, industry, and livestock production (Figure 13.5, left). The average American directly uses about 370 liters (98 gallons) of freshwater a day—enough water to fill 2.5 typical bathtubs. (The average bathtub can contain about 151 liters or 40 gallons of water.) Household water is used mostly for flushing toilets, washing clothes, taking showers, and running faucets, or is lost through leaking pipes, faucets, and other fixtures (Figure 13.5, right).
Figure 13.5
Comparison of primary uses of water in the United States (left) and uses of water in a typical U.S. household (right).
Data Analysis:
1. In the right-hand chart, which three categories, added together, are smaller than the amount of water lost in leaks?
(Compiled by the authors using data from U.S. Geological Survey, World Resources Institute, and American Water Works Association.)
The United States has more than enough renewable freshwater to meet its needs. However, it is unevenly distributed and much of it is contaminated by agricultural and industrial practices. The eastern states usually have ample precipitation, whereas many western and southwestern states have little (Figure 13.6).
Figure 13.6
Long-term average annual precipitation and major rivers in the continental United States.
(Compiled by the authors using data from U.S. Water Resources Council and U.S. Geological Survey.)
In the eastern United States, most water is used for manufacturing and for cooling power plants (with most of the water heated and returned to its source). In many parts of this area, the most serious water problems are flooding, occasional water shortages because of drought, and pollution.
In the arid and semiarid regions of the western half of the United States (Core Case Study), irrigation counts for as much as 85% of freshwater use. Much of it is lost to evaporation and a great deal of it is used to grow crops that require a lot of water. The major water problem is a shortage of freshwater runoff caused by low precipitation (Figure 13.6), high evaporation, and recurring prolonged drought.
Groundwater is one of the most precious of all U.S. resources. About half of all Americans (and 95% of all rural residents) rely on it for drinking water. It makes up about half of all irrigation water, feeds about 40% of the country’s streams and rivers, and provides about one-third of the water used by U.S. industries.
Water tables in many water-short areas, especially in the dry western states, are dropping as farmers and rapidly growing urban areas draw down many aquifers faster than they can be recharged. The U.S. Department of the Interior has mapped out water scarcity hotspots in 17 western states (Figure 13.7). In these areas, there is competition for scarce freshwater to support growing urban areas, irrigation, recreation, and wildlife. This competition for freshwater could trigger intense political and legal conflicts between states and between rural and urban areas within states. In addition, Columbia University climate researchers led by Richard Seager used well-tested climate models to project that the southwestern United States is very likely to have long periods of extreme drought throughout most of the rest of this century.
Figure 13.7
Water scarcity hotspots in 17 western states that, by 2025, could face intense conflicts over scarce water needed for urban growth, irrigation, recreation, and wildlife.
Question:
1. Which, if any, of these areas are found in the Colorado River basin (Core Case Study)?
(Compiled by the authors using data from U.S. Department of the Interior and U.S. Geological Survey.)
The Colorado River system (Figure 13.1) is directly affected by such drought. There are three major problems associated with the use of freshwater from this river (Core Case Study). First, the Colorado River basin includes some of the driest lands in the United States and Mexico. Second, long-standing legal agreements between Mexico and the affected western states allocated more freshwater for human use than the river can supply, even in rare years when there is no drought. These pacts allocated no water for protecting aquatic and terrestrial wildlife. Third, since 1960, because of drought, damming, and heavy withdrawals, the river has rarely flowed all the way to the Gulf of California and this has degraded the river’s aquatic ecosystems and dried up its delta (which we discuss later in this chapter).
Freshwater that is not directly consumed but is used to produce food and other products is called
virtual water
. It makes up a large part of the water footprints of individuals, especially in more-developed countries. Agriculture accounts for the largest share of humanity’s water footprint. Producing and delivering a typical quarter-pound hamburger, for example, takes about 2,400 liters (630 gallons or 16 bathtubs) of freshwater—most of it used to grow grain to feed cattle. Producing a smart phone requires about 910 liters (240 gallons or 6 bathtubs) of freshwater. Figure 13.4 shows one way to measure the amounts of virtual water used for producing and delivering products. These values can vary depending on how much of the supply chain is included, but they give us a rough estimate of the size of our water footprints.
Figure 13.4
Producing and delivering a single one of each of the products listed here requires the equivalent of nearly one and usually many bathtubs full of freshwater, called virtual water.
(Compiled by the authors using data from UN Food and Agriculture Organization, UNESCO-IHE Institute for Water Education, World Water Council, and Water Footprint Network.); Bathtub: Baloncici/ Shutterstock.com. Coffee: Aleksandra Nadeina/ Shutterstock.com. Bread: Alexander Kalina/ Shutterstock.com. Hamburger: Joe Belanger/ Shutterstock.com. T-shirt: grmarc/ Shutterstock.com. Jeans: Eyes wide/ Shutterstock.com. Car: L Barnwell/ Shutterstock.com. House: Rafal Olechowski/ Shutterstock.com
Note: .
Because of global trade, the virtual water used to produce and transport products such as coffee and wheat (also called embedded water) is often withdrawn as groundwater or surface water in another part of the world. Thus, water can be imported in the form of products, often from countries that are short of water.
Large exporters of virtual water—mostly in the form of wheat, corn, soybeans, and other foods—are the European Union, the United States, Canada, Brazil, India, and Australia. Indeed, Brazil’s supply of freshwater per person is more than 8 times the U.S. supply per person, 14 times China’s supply, and 29 times India’s supply. Brazil is becoming one of the world’s largest exporters of virtual water. However, prolonged severe droughts in parts of Australia, the United States, and the European Union are stressing the abilities of these countries to meet the growing global demand for their food exports.
· 13.1dWater Use Is Increasing
· According to hydrologists, scientists who study water and its properties and movement, two-thirds of the annual surface runoff of freshwater into rivers and streams is lost in seasonal floods and is not available for human use. The remaining one-third is reliable surface runoff—defined as the portion of runoff that is regarded as a stable source of freshwater from year to year. GREEN CAREER: Hydrologist
· Since 1900, the human population tripled, global water withdrawals increased sevenfold, and per capita water withdrawals quadrupled. As a result, we now withdraw an estimated 34% of the world’s reliable runoff. This is a global average. In the arid American southwest, up to 70% of the reliable runoff is withdrawn for human purposes, mostly for irrigation. Some water experts project that because of population growth, rising rates of water use per person, longer dry periods in some areas, and unnecessary water waste, we are likely to be withdrawing up to 90% of the world’s reliable freshwater runoff by 2025.
· Worldwide, we use 70% of the freshwater we withdraw each year from rivers, lakes, and aquifers to irrigate cropland and raise livestock. In arid regions, up to 90% of the regional water supply is used for food production. Industry uses roughly another 20% of the water withdrawn globally each year. Cities and residences use the remaining 10%.
· Your water footprint is a rough measure of the volume of freshwater that you use directly or indirectly. Your daily water footprint includes the freshwater you use directly (for example, to drink, bathe, or flush a toilet) and the water you use indirectly through the food, energy, and products you consume. (See the Case Study that follows for information on U.S. water use.) The three largest water footprints in the world belong to India, the United States, and China, in that order.
· Case Study
· Freshwater Resources in the United States
· According to the U.S. Geological Survey (USGS), the major uses of groundwater and surface freshwater in the United States are the cooling of electric power plants, irrigation, public water supplies, industry, and livestock production (Figure 13.5, left). The average American directly uses about 370 liters (98 gallons) of freshwater a day—enough water to fill 2.5 typical bathtubs. (The average bathtub can contain about 151 liters or 40 gallons of water.) Household water is used mostly for flushing toilets, washing clothes, taking showers, and running faucets, or is lost through leaking pipes, faucets, and other fixtures (Figure 13.5, right).
· Figure 13.5
· Comparison of primary uses of water in the United States (left) and uses of water in a typical U.S. household (right).
· Data Analysis:
· In the right-hand chart, which three categories, added together, are smaller than the amount of water lost in leaks?
·
· (Compiled by the authors using data from U.S. Geological Survey, World Resources Institute, and American Water Works Association.)
· The United States has more than enough renewable freshwater to meet its needs. However, it is unevenly distributed and much of it is contaminated by agricultural and industrial practices. The eastern states usually have ample precipitation, whereas many western and southwestern states have little (Figure 13.6).
· Figure 13.6
· Long-term average annual precipitation and major rivers in the continental United States.
·
· (Compiled by the authors using data from U.S. Water Resources Council and U.S. Geological Survey.)
· In the eastern United States, most water is used for manufacturing and for cooling power plants (with most of the water heated and returned to its source). In many parts of this area, the most serious water problems are flooding, occasional water shortages because of drought, and pollution.
· In the arid and semiarid regions of the western half of the United States (Core Case Study), irrigation counts for as much as 85% of freshwater use. Much of it is lost to evaporation and a great deal of it is used to grow crops that require a lot of water. The major water problem is a shortage of freshwater runoff caused by low precipitation (Figure 13.6), high evaporation, and recurring prolonged drought.
· Groundwater is one of the most precious of all U.S. resources. About half of all Americans (and 95% of all rural residents) rely on it for drinking water. It makes up about half of all irrigation water, feeds about 40% of the country’s streams and rivers, and provides about one-third of the water used by U.S. industries.
· Water tables in many water-short areas, especially in the dry western states, are dropping as farmers and rapidly growing urban areas draw down many aquifers faster than they can be recharged. The U.S. Department of the Interior has mapped out water scarcity hotspots in 17 western states (Figure 13.7). In these areas, there is competition for scarce freshwater to support growing urban areas, irrigation, recreation, and wildlife. This competition for freshwater could trigger intense political and legal conflicts between states and between rural and urban areas within states. In addition, Columbia University climate researchers led by Richard Seager used well-tested climate models to project that the southwestern United States is very likely to have long periods of extreme drought throughout most of the rest of this century.
· Figure 13.7
· Water scarcity hotspots in 17 western states that, by 2025, could face intense conflicts over scarce water needed for urban growth, irrigation, recreation, and wildlife.
· Question:
· Which, if any, of these areas are found in the Colorado River basin (Core Case Study)?
·
· (Compiled by the authors using data from U.S. Department of the Interior and U.S. Geological Survey.)
· The Colorado River system (Figure 13.1) is directly affected by such drought. There are three major problems associated with the use of freshwater from this river (Core Case Study). First, the Colorado River basin includes some of the driest lands in the United States and Mexico. Second, long-standing legal agreements between Mexico and the affected western states allocated more freshwater for human use than the river can supply, even in rare years when there is no drought. These pacts allocated no water for protecting aquatic and terrestrial wildlife. Third, since 1960, because of drought, damming, and heavy withdrawals, the river has rarely flowed all the way to the Gulf of California and this has degraded the river’s aquatic ecosystems and dried up its delta (which we discuss later in this chapter).
· Freshwater that is not directly consumed but is used to produce food and other products is called virtual water. It makes up a large part of the water footprints of individuals, especially in more-developed countries. Agriculture accounts for the largest share of humanity’s water footprint. Producing and delivering a typical quarter-pound hamburger, for example, takes about 2,400 liters (630 gallons or 16 bathtubs) of freshwater—most of it used to grow grain to feed cattle. Producing a smart phone requires about 910 liters (240 gallons or 6 bathtubs) of freshwater. Figure 13.4 shows one way to measure the amounts of virtual water used for producing and delivering products. These values can vary depending on how much of the supply chain is included, but they give us a rough estimate of the size of our water footprints.
· Figure 13.4
· Producing and delivering a single one of each of the products listed here requires the equivalent of nearly one and usually many bathtubs full of freshwater, called virtual water.
·
·
· (Compiled by the authors using data from UN Food and Agriculture …
G. Tyler Miller, Scott E. Spoolman
Living in the Environment
20th Edition
14.2a
Nonrenewable Mineral Resources Can Be Economically Depleted
Most published estimates of the supply of a given nonrenewable mineral resource refer to its reserves: identified deposits from which we can extract the mineral profitably at current prices. Reserves can be expanded when we find new, profitable deposits or when higher prices or improved mining technologies make it profitable to extract deposits that previously were too expensive to remove.
The future supply of any nonrenewable mineral resource depends on the actual or potential supply of the mineral and the rate at which it is used. Society has never completely run out of a nonrenewable mineral resource. However, a mineral becomes economically depleted when it costs more than it is worth to find, extract, transport, and process the remaining deposits. At that point, there are five choices: recycle or reuse existing supplies, waste less, use less, find a substitute, or do without.
Depletion time is the time it takes to use up a certain proportion—usually 80%—of the reserves of a mineral at a given rate of use. When experts disagree about depletion times, it is often because they are using different assumptions about supplies and rates of use (Figure 14.4).
Figure 14.4
Natural capital depletion: Each of these depletion curves for a mineral resource is based on a different set of assumptions. Dashed vertical lines represent the times at which 80% depletion occurs.
A graph with three curves indicating the depletion of mineral resources. The graph is plotted with time on X-axis and the production on Y-axis. Curve A indicates a great increase in production within a very short time period and then falls drastically to zero level within a short time period. The supporting text associated with the curve reads “Mine, use, throw away; no new discoveries; rising prices”. About 80 percent of depletion of the mineral resources is indicated at a time just after the production begins to fall and is labeled “Depletion time A”. Curve B depicts a gradual increase in production with time and similarly the decrease in production is observed gradually with time. The supporting text associated with the curve reads “Recycle, increase reserves by improved mining technology, higher prices and new discoveries”. About 80 percent depletion of the resources is indicated at a time when the production drops to nearly half compared to the peak production and is labeled “Depletion time B”. Curve C depicts a very slow increase in production with time and the drop in production is also very slow. The supporting text associated with the curve reads “Recycle, reuse, reduce consumption; increase reserves by improved mining technology, higher prices and new discoveries”. About 80 percent depletion of resources is indicated at a time when the production drops to about 75 percent compared to the peak and is labeled “Depletion time C”.
The shortest depletion-time estimate assumes no recycling or reuse and no increase in the reserve (curve A, Figure 14.4). A longer depletion-time estimate assumes that recycling will stretch the existing reserve and that better mining technology, higher prices, or new discoveries will increase the reserve (curve B). The longest depletion-time estimate (curve C) makes the same assumptions as those for curve B and assumes that people will reuse and reduce consumption to expand the reserve further. Finding a substitute for a resource leads to a new set of depletion curves for the new mineral.
The earth’s crust contains abundant deposits of nonrenewable mineral resources such as iron and aluminum. However, concentrated deposits of important mineral resources such as manganese, chromium, cobalt, platinum, and rare earth elements (see the Case Study that follows) are relatively scarce. In addition, deposits of many mineral resources are not distributed evenly among countries. Five nations—the United States, Canada, Russia, South Africa, and Australia—supply most of the nonrenewable mineral resources that modern societies use.
Since 1900, and especially since 1950, there has been a sharp rise in the total and per capita use of mineral resources in the United States. According to the USGS, each American directly and indirectly uses an average of 18.4 metric tons (20.3 tons) of mineral resources per year.
The United States has economically depleted some of its once-rich deposits of metals such as lead, aluminum, and iron. In 2018, the United States imported all of its supplies of 21 key nonrenewable mineral resources and for 32 other minerals and relied on imports for more than half of its supplies. Most of these mineral imports come from reliable and politically stable countries. However, there are serious concerns about access to adequate supplies of four strategic metal resources—manganese, cobalt, chromium, and platinum—that are essential for the country’s economic and military strength. The United States has little or no reserves of these metals. China is a major global supplier of crucial minerals such as arsenic to make semiconductors, tungsten found in heating elements and light bulbs, and cadmium used in rechargeable batteries.
Lithium (Li), the world’s lightest metal, is a vital component of lithium-ion batteries, which are used in cell phones, iPads, laptop computers, electric cars, and a growing number of other products. The problem is that some countries, including the United States, do not have large supplies of lithium. Bolivia has about 50% of these reserves, whereas the United States holds only about 3%.
Japan, China, South Korea, and the United Arab Emirates have been buying up access to global lithium reserves to ensure their ability to sell lithium and lithium-ion batteries to the rest of the world. Within a few decades, the United States may be heavily dependent on expensive imports of lithium and lithium-ion batteries. A company is building a plant in California that is designed to extract lithium from brine waste produced by geothermal power plants. If it is successful, this process could lessen some U.S. dependence on imported lithium.
The demand for cobalt, which is widely used in lithium-ion electric-car batteries, magnets, and smartphones has been rising sharply. According to the Bank of America, electric vehicles will account for 34% of all global vehicle sales by 2030, which is expected to triple the global demand for cobalt. In 2019, the three largest producers of cobalt, in order, were the Democratic Republic of Congo (by far the largest producer), Russia, and Cuba. Because China is the world’s largest producer of electric cars and lithium ion batteries, it is buying up access to much of the world’s current and future cobalt production from the Democratic Republic of Congo.
Case Study
The Importance of Rare Earth Metals
Some mineral resources are familiar, such as gold, copper, aluminum, sand, and gravel. Less well known are the rare earth metals and oxides, which are crucial to many technologies that support modern lifestyles and economies.
The 17 rare earth metals, also known as rare earths, include scandium, yttrium, and 15 lanthanide chemical elements, including lanthanum. Because of their superior magnetic strength and other unique properties, these elements and their compounds are important for a number of widely used technologies.
Rare earths are used to make liquid crystal display (LCD) flat screens for computers and television sets, energy-efficient light-emitting diode (LED) light bulbs, solar cells, fiber-optic cables, smart phones, and digital cameras. Rare earths are also part of batteries and motors for electric and hybrid-electric cars (Figure 14.5), catalytic converters in car exhaust systems, jet engines, and the powerful magnets in wind turbine generators. Rare earths also go into missile guidance systems, smart bombs, aircraft electronics, and satellites.
Figure 14.5
Manufacturers of all-electric and hybrid-electric cars and other products use a variety of rare earth metals.
An illustration depicting various metals used in the manufacture of electric and hybrid electric cars and other products. An image of car depicting the internal parts of the car has three call outs. A call out pointing to the motor region (represented as a two interconnected drums near the front wheel region) reads, “Electric motors and generator: Dysprosium, Neodymium, Praseodymium, and Terbium.” A call out pointing to the battery (represented as a long yellow rectangle laid flat near the back wheel region) reads, “Battery” Lanthanum, Cerium.” A call out pointing the catalytic converter (represented as small blue rectangle laid flat near the back wheel region) reads, “Catalytic converter: Cerium, Lanthanum”. An image of the windmill (represented as a long pole with three huge blades attached at the tip) reads, “Neodymium.” An image of the camera (represented as a small rectangle with multiple sections and a projection in the front) reads, “Praseodymium.” An image of the monitor (represented as a black rectangle with bright white black center mounted on a small stand) reads, “Europium, Yttrium.”
Without affordable supplies of these metals, industrialized nations could not develop the current versions of cleaner energy technology and other high-tech products that will be major sources of economic growth during this century. Many nations also need these metals to maintain their military strength.
Most rare earth elements are not actually rare, but they are hard to find in concentrations high enough to extract and process at an affordable price. China has the largest share (37%) of the world’s known rare-earth reserves. In 2018, it accounted for 96% of the global mining output of rare-earth metals and in 2019 China gained control of the remaining 4% rare-earth production by acquiring the Molycorp rare-earth mine in Mountain Pass, California. This gives China control over the global price of its rare earth metal exports. China also dominates research and development of rare earth metals. The United States and Japan are heavily dependent on rare earths and their oxides. However, the United States produces no rare earths and has only 1.2% of the global rare-earth reserves. Japan has no rare-earth reserves.
One way to increase supplies of rare earths is to extract and recycle them from the massive amounts of electronic wastes that are being produced. It can also be extracted from large piles of phosphogypsum, a waste product of fertilizer manufacturing. So far, however, less than 1% of rare earth metals are recovered and recycled. Another approach is to find substitutes for rare earth metals. In 2016, Honda produced a hybrid electric car engine with magnets that do not need heavy rare-earth metals and that are 10% cheaper and 8% lighter. 14.2bMarket Prices and Supplies of Mineral Resources
Geological processes determine the quantity and location of a mineral resource in the earth’s crust, but economics determines what part of the known supply is extracted and used. According to standard economic theory, in a competitive market system when a resource becomes scarce, its price rises. Higher prices can encourage exploration for new deposits, stimulate development of better mining technology, and make it profitable to mine lower-grade ores. Higher prices can also promote resource conservation and a search for substitutes.
Connections
High Metal Prices and Thievery
Resource scarcity can promote theft. For example, copper prices have risen sharply in recent years because of increasing demand. As a result, in many U.S. communities, thieves have been stealing copper to sell it. They strip abandoned houses of copper pipe and wiring and steal outdoor central air conditioning units for their copper coils. They also steal wiring from beneath city streets and copper piping from farm irrigation systems. In 2015, thieves stole copper wiring from New York City’s subway system, temporarily shutting down two of the city’s busiest lines.
Generally, the mining industry maintains that they need subsidies and tax breaks to keep the prices of minerals low for consumers. They also claim that, without subsidies and tax breaks, they might move their operations to other countries where they would not have to pay taxes or comply with strict mining and pollution control regulations.
14.2cMining Lower-Grade Ores
Some analysts contend that we can increase supplies of some minerals by extracting them from lower-grade ores. They point to the development of new earth-moving equipment, improved techniques for removing impurities from ores, and other technological advances in mineral extraction and processing that can make lower-grade ores more accessible, sometimes at lower costs. For example, in 1900, the copper ore mined in the United States was typically about 5% copper by weight. Today, it is typically about 0.5%, yet copper costs less (when prices are adjusted for inflation).
Several factors can limit the mining of lower-grade ores. For example, it requires mining and processing larger volumes of ore, which takes much more energy and costs more. Another factor is the dwindling supplies of freshwater needed for the mining and processing of some minerals, especially in dry areas. A third limiting factor is the growing environmental impacts of land disruption, along with waste material and pollution produced during the mining and processing of minerals.
One way to improve mining technology and reduce its environmental impact is to use a biological approach, sometimes called biomining. Miners use naturally occurring or genetically engineered bacteria to remove desired metals from ores through wells bored into the deposits. This leaves the surrounding environment undisturbed and reduces the air and water pollution associated with removing the metal from metal ores. On the downside, biomining is slow. It can take decades to remove the same amount of material that conventional methods can remove within months or years. So far, biomining methods are economically feasible only for low-grade ores for which conventional techniques are too expensive.
14.2dMinerals from the Oceans
Most of the minerals found in seawater occur in such low concentrations that recovering them takes more energy and money than they are worth. Currently, only magnesium, bromine, and sodium chloride are abundant enough to be extracted profitably from seawater. On the other hand, sediments along the shallow continental shelf and adjacent shorelines contain significant deposits of minerals such as sand, gravel, phosphates, copper, iron, silver, titanium, and diamonds.
Another potential ocean source of some minerals is hydrothermal ore deposits that form when superheated, mineral-rich water shoots out of vents in volcanic regions of the ocean floor. As the hot water meets cold seawater, black particles of various metal sulfides precipitate out and accumulate as chimney-like structures, called black smokers, near the hot water vents (
). These deposits are especially rich in minerals such as copper, lead, zinc, silver, gold, and some of the rare earth metals. Exotic communities of marine life—including giant clams, six-foot tubeworms, and eyeless shrimp—live in the dark depths around black smokers. Companies from Australia, the United States, and China have been exploring the possibility of mining black smokers in several areas.
Figure 14.6
Natural capital: Hydrothermal deposits, or black smokers, are rich in various minerals.
Another possible source of metals is the potato-size manganese nodules that cover large areas of the Pacific Ocean floor and smaller areas of the Atlantic and Indian Ocean floors. They also contain low concentrations of various rare earth minerals. These modules could be sucked up through vacuum pipes or scooped up by underwater mining machines.
The United Nations International Seabed Authority, established to manage seafloor mining in international waters, began issuing mining permits in 2011. However, mining on the ocean floor has been hindered by the high costs involved, the potential threat to marine ecosystems, and arguments over rights to the minerals in deep ocean areas that do not belong to any specific country.
Learning from Nature
A bacterium that lives in the manganese nodules on the ocean floor is being used to make mining of these nodules less costly. Scientists from India have learned how to employ the bacterium to remove the precious metals from the nodules at room temperature. This could also help to lessen the harmful environmental effects of separating metals from their ores.
14.3aHarmful Environmental Effects of Extracting Minerals
Every metal product has a life cycle that includes mining the mineral, processing it, manufacturing the product, and disposal or recycling of the product (Figure 14.7). This process makes use of large amounts of energy and water, and produces pollution and waste at every step of the life cycle.
Figure 14.7
Each metal product that we use has a life cycle.
Left: kaband/ Shutterstock.com. Second to left: Andrey N Bannov/ Shutterstock.com. Center left: Vladimir Melnik/ Shutterstock.com. Center: mares/ Shutterstock.com. Center right: Zhu Difeng/ Shutterstock.com. Second to right: Michael Shake/ Shutterstock.com. Right: Pakhnyushchy/ Shutterstock.com.
The environmental impacts of mining a metal ore are determined partly by the ore’s percentage of metal content, or grade. The more accessible higher-grade ores are usually exploited first. Mining lower-grade ores takes more money, energy, water, and other resources, and leads to more land disruption, mining waste, and pollution.
Several mining techniques are used to remove mineral deposits. Shallow mineral deposits are removed by
surface mining
, in which vegetation, soil, and rock overlying a mineral deposit are cleared away. This waste material is called
overburden
and is usually deposited in piles called
spoils
(Figure 14.8). Surface mining is used to extract about 90% of the nonfuel mineral resources and 60% of the coal used in the United States.
Figure 14.8
Natural capital degradation: This spoils pile in Zielitz, Germany, is made up of waste material from the mining of potassium salts used to make fertilizers.
Different types of surface mining can be used, depending on two factors: the resource being sought and the local topography. In
open-pit mining
, machines are used to dig large pits and remove metal ores containing copper, gold (Core Case Study), or other metals, or sand, gravel, or stone. The open-pit copper mine shown in the opening photo for this chapter is almost 5 kilometers (3 miles) wide and 1,200 meters (4,000 feet) deep, and is getting deeper.
9 Million
Number of people who could sit in Bingham Copper Mine (see chapter-opening photo) if it were a stadium
Strip mining involves extracting mineral deposits that lie in large horizontal beds close to the earth’s surface. In
area strip mining
, used on flat terrain, a gigantic earthmover strips away the overburden, and a power shovel—which can be as tall as a 20-story building—removes a mineral resource such as gold (Figure 14.9). The resulting trench is filled with overburden, and a new cut is made parallel to the previous one. This process is repeated over the entire site.
Figure 14.9
Natural capital degradation: Area strip-mining for gold in Yukon Territory, Canada.
Paul Nicklen/National Geographic Image Collection
Contour strip mining
(Figure 14.10) is used mostly to mine coal and various mineral resources on hilly or mountainous terrain. Huge power shovels and bulldozers cut a series of terraces into the side of a hill. Then, earthmovers remove the overburden, an excavator or power shovel extracts the coal, and the overburden from each new terrace is dumped onto the one below. Unless the land is restored, this leaves a series of spoils banks and a highly erodible hill of soil and rock called a highwall.
Figure 14.10
Natural capital degradation: Contour strip mining is used in hilly or mountainous terrain.
Another surface mining method is
mountaintop removal
, in which explosives are used to remove the top of a mountain to expose seams of coal that are then extracted (Figure 14.11). After a mountaintop is blown apart, enormous machines plow waste rock and dirt into valleys below the mountaintops. This destroys forests, buries mountain streams, and increases the risk of flooding. Wastewater and toxic sludge, produced when the coal is processed, are often stored behind dams in these valleys. Some dams have overflowed or collapsed and released toxic substances such as arsenic and mercury.
Figure 14.11
Natural capital degradation: Mountaintop removal coal mining near Whitesville, West Virginia.
Jim West/Age Fotostock
In the United States, more than 500 mountaintops in West Virginia and other Appalachian states have been removed to extract coal (Figure 14.11). According to the U.S. Environmental Protection Agency (EPA), the resulting spoils have buried more than 1,100 kilometers (700 miles) of streams.
The U.S. Surface Control and Reclamation Act of 1997 requires mining companies to restore mines abandoned before 1977 and companies are required to restore active mines and mines abandoned after 1977. However, the program is greatly underfunded and many mines have not been reclaimed.
Deep deposits of minerals are removed by
subsurface mining
, in which underground mineral resources are removed through tunnels and shafts (Figure 14.12). This method is used to remove metal ores and coal that are too deep to be extracted by surface mining. Miners dig a deep, vertical shaft and blast open subsurface tunnels and chambers to reach the deposit. Then they use machinery to remove the resource and transport it to the surface.
Figure 14.12
Subsurface mining of coal.
Subsurface mining disturbs less than one-tenth as much land as surface mining, and usually produces less waste material. However, the environmental damage is significant and can lead to other hazards such as cave-ins, explosions, and fires for miners. Miners often get lung diseases caused by prolonged inhalation of mineral or coal dust in subsurface mines. Another problem is subsidence—the collapse of land above some underground mines. It can damage houses, crack sewer lines, break natural gas mains, and disrupt groundwater systems. Subsurface mining also requires large amounts of water and energy to process and transport the mined material.
Collectively, surface and subsurface mining operations produce three-fourths of all U.S. solid waste and cause major water and air pollution. For example, acid mine drainage occurs when rainwater seeps through an underground mine or a spoils pile from a surface mine. Such water can contain sulfuric acid , produced when aerobic bacteria act on minerals in the spoils. This toxic runoff can pollute nearby streams and groundwater—one of the problems often associated with gold mining (Core Case Study).
According to the EPA, mining has polluted mountain streams in 40% of the western watersheds in the United States. It also accounts for half of all the country’s emissions of toxic chemicals into the atmosphere. In fact, the mining industry produces more of such toxic emissions than any other U.S. industry.
Mining can be even more harmful to the environment in countries where environmental regulations are lacking or not reliably enforced. In China, for instance, the mining and processing of rare earth metals and oxides has stripped land of its vegetation and topsoil. It also has polluted the air, acidified streams, and left toxic and radioactive waste piles.
14.3bEnvironmental Effects of Removing Metals from Ores
Ore extracted by mining typically has two components: the ore mineral that contains the desired metal and waste material. Removing the waste material from ores produces
tailings
—rock wastes that are left in piles or put into ponds where they settle out. Particles of toxic metals in tailings piles can be blown by the wind, washed out by rain, or leak from holding ponds, which can contaminate surface water and groundwater.
After the waste material is removed, heat or chemical solvents are used to extract the metals from mineral ores. Heating ores to release metals is called
smelting
(
). Without effective pollution control equipment, a smelter emits large quantities of air pollutants. These pollutants include sulfur dioxide and suspended toxic particles that damage vegetation and acidify soils in the surrounding area. Smelters also cause water pollution and produce liquid and solid hazardous wastes that require safe disposal. A 2012 study found that lead smelting is the world’s second most toxic industry after the recycling of lead-acid batteries.
Using chemicals to extract metals from their ores can also create pollution and health problems, as we saw in the case of using cyanide to remove gold (
). Millions of poverty-stricken miners in less-developed countries have gone into tropical forests in search of gold. They have cleared trees to get access to gold, and such illegal deforestation has increased rapidly, especially parts of the Amazon Basin and in Africa (
). In these small-scale and illegal gold mines, miners use toxic mercury to separate gold from its ore. They heat the mixture of gold and mercury to vaporize the mercury and leave the gold, causing dangerous air and water pollution. They leave behind land stripped of vegetation and topsoil loaded with toxic mercury. Many of the miners and villagers living near the mines eventually inhale toxic mercury vapor, drink mercury-laden water, or eat fish contaminated with mercury.
Figure 14.13
Illegal gold mining on the banks of the Pra River in Ghana, Africa.
Randy Olson/National Geographic Image Collection
14.4aFinding Substitutes for Scarce Mineral Resources
Some analysts believe that even if supplies of key minerals become too expensive or too scarce due to unsustainable use, human ingenuity will find substitutes. They point to the current materials revolution in which silicon and other materials are replacing some metals for common uses. They also point out the possibilities of finding substitutes for scarce minerals through nanotechnology (Science Focus 14.1), and other emerging technologies (see Case Study that follows).
Science Focus 14.1
The Nanotechnology Revolution
Nanotechnology
uses science and engineering to manipulate and create materials out of atoms and molecules at the ultra-small scale of less than 100 nanometers. The diameter of the period at the end of this sentence is about a half million nanometers.
Currently, nanomaterials are used in more than 1,300 consumer products and the number is growing. Such products include certain batteries, stain-resistant and wrinkle-free clothes, self-cleaning glass surfaces, self-cleaning sinks and toilets, sunscreens, waterproof coatings for cell phones, some cosmetics, some foods, and food containers that release nanosilver ions to kill bacteria, molds, and fungi.
Nanotechnologists envision innovations such as a supercomputer smaller than a grain of rice, thin and flexible solar cell films that could be attached to or painted onto almost any surface, and materials that would make our bones and tendons super strong. Some nanomolecules could be designed to seek out and kill cancer cells or to eliminate the need for allergy shots. Scientists are working on a wearable graphene patch that would help diabetics manage their blood glucose levels …
ENV330 Module 4 AVP Transcript
Title Slide
Narrator: In Module 4, we will consider the impact of food production and distribution and sustainable
food production. The total amount of food grown and produced for humans has increased dramatically
over the past 50 years to meet the growing demands of our human population. Agricultural production,
meat production and fish catch, both wild caught and aquaculture have all increased dramatically. The
world’s three largest grain-producing countries are China, the United States, and India.
What kinds of stresses has this placed on the natural capital and ecosystems of the world?
Slide 2
Title: Impacts of Food Production
Slide content:
[image of a desert]
Narrator: The impacts include loss of biodiversity, soil degradation, wasting and pollution of scarce water
resources, increased greenhouse gas emissions, depletion of fish stocks in the oceans, and human
health problems. According to a 2002 study by the United Nations, nearly 30% of the world’s cropland
has been degraded to some degree by soil erosion, salt buildup, and chemical pollution, and 17% has
been seriously degraded.
There are serious soil erosion problems on every continent of the world, and marine biologists say that
we’ve “fished out” much of the oceans.
Slide 3
Title: Dust Bowl in 1930’s
Slide Content:
[black and white image of a dust cloud taking over a town]
Narrator: Overgrazing, poor agricultural practices including salinization from irrigation can cause erosion,
desertification and dust storms. Deforestation of hillsides can also impact agriculture and ecosystems.
Once a hillside has been deforested for timber, fuelwood, livestock grazing, or unsustainable farming,
water from precipitation rushes down the denuded slopes, erodes precious topsoil, and can increase
flooding and pollution in local streams. Such deforestation can also increase landslides and mudflows. A
3,000-year-old Chinese proverb says, “To protect your rivers, protect your mountains.”
Waste of water is one of the major environmental problems associated with agriculture. The most
efficient (90-95%) way to get water to the roots of crops is through drip irrigation, or Low Energy Precision
Application (LEPA), which you will learn about in this module.
During the Dust Bowl in the US in the 1930’s, terribly unsustainable agricultural practices in the Midwest
breadbasket led to such dire conditions that millions of starving people migrated away from the farmlands.
Many children died from inhaling the dust. The situation got so bad that during a Senate hearing on the
issue in DC, dust from a dust storm leaked into the conference room!
A few inches of top soil is all that keeps civilization from starvation – we need to protect this vital natural
capital.
Slide 4
Title: Industrialized Agriculture
Slide Content:
[image of farm equipment on an empty field]
Narrator: Industrialized agriculture uses about 17% of all commercial energy used in the US. 5% is for
used for transporting food the average 1300 miles from farm to plate in the US. The resulting pollution
degrades the air and water.
What effects do you think industrialized agriculture has on Global Climate Change?
As Rajendra Pachauri, head of the UN Intergovernmental Panel on Climate Change puts it, “We need to
start eating as if Earth’s climate mattered.”
Chemical pesticides used in industrial agriculture are another issue with grave ecological and
environmental effects. Farmers use many tons of them on every crop leading to genetic resistance by
insects and other agricultural pests, pollution of steams and poisoning of wildlife, contamination of food,
and they kill natural pests’ enemies.
Organic farming avoids these problems.
Additionally, there are many ways to protect soil and minimize erosion, including: terracing, contour
plowing, strip cropping, alley cropping, and windbreaks.
You will learn about these and other sustainable farming techniques in this module.
Slide 5
Title: Factory Meat Farming
Slide Content:
[image of pigs in a barn]
Narrator: The US grows and kills nearly 10 billion animals a year despite making up only 4.5% of the
world’s population. The use of animal feedlots has increased dramatically during the last few decades.
In addition to the ethical issues related to animal cruelty in horrendously crowded conditions, many
serious environmental problems are caused by feedlots and factory meat farming. For example, the
concentrated poultry and hog houses produce as much sewage as cities, leading to eutrophication
problems in streams, rivers and coastal areas when the nutrients enter those waters. The excess
nutrients stimulate rapid algal growth, called an algal “bloom”. The water becomes cloudy and blocks the
light leading to massive die-off of the algae. Microbial decomposition uses up most of the dissolved O2 ,
leading to massive “dead zones” in which fish and other animals suffocate.
Meat production also requires much more energy than growing grain. Due again to the 2
nd
Law of
Energy, and the energy pyramid, up to 90% of the energy in grain fed to animals is converted into low
quality waste heat energy. Therefore, it takes 7 lbs. of grain to create 1 lb. of beef, and 4 lbs. of grain to
produce 1 lb. of pork. The efficiency of producing chicken and fish is much higher – a 45% and 50%
conversion of grain energy to meat energy. Of course, a vegetarian diet eliminates all of this lost food
energy.
Aquaculture, the raising of seafood in large enclosures, offers some advantages but also has
disadvantages. You will learn about aquaculture in this module.
QUESTION: Why do most people in poor overpopulated societies subsist mainly on a vegetarian diet?
Yes, it’s much more efficient to feed the crops directly to people and thereby eliminate the inefficient
conversion of plants to meat with up to 90% conversion of plant energy to waste heat energy due to the
2
nd
Law of Energy. You can feed 10-20 times as many people from the same amount of land if you
eliminate the livestock.
ANOTHER QUESTION: Who will eat meat when the human population of the Earth doubles again to 12
or 13 billion?
Answer: Perhaps no one!! It could become a distant memory only remembered in tales told by old
grandfathers.
ETHICAL QUESTION: Is it ethical to eat meat on an overcrowded planet where thousands of children die
from malnutrition each day?
I’m going to let you ponder those questions. And while you are pondering, we can all help by wasting
less food, eating less or no meat, using organic farming to grow some of our own food, buying organic
food, eating locally grown food, and composting .
To create sustainable agriculture we need to mimic nature.
End of Presentation
