U.S. Economy
Информация - Экономика
Другие материалы по предмету Экономика
pruce along the coast of Alaska. Forests in the mountain states of the West cover a relatively small area, yet they account for more than 10 percent of the nations lumber production. Ponderosa pine is the most important species cut from the forests of this area.
Forests in the South supply about one-third of the lumber, nearly three-fifths of the pulpwood, and almost all the turpentine, pitch, resin, and wood tar produced in the United States. Longleaf, shortleaf, loblolly, and slash pine are the most important commercial trees of the southern coastal plain. Commercially valuable hardwood trees, such as gum, ash, pecan, and oak, grow in the lowlands along the rivers of the South.
The Appalachian Highland and parts of the Great Lakes area have excellent hardwood forests. Hickory, maple, oak, and other hardwoods removed from these forests provide fine woods for the manufacture of furniture and other products.
In the 1990s the forest products industry was undergoing a transformation. New environmental requirements, designed to protect wildlife habitat and water resources, were changing forest practices, particularly in the West. The amount of timber cut on federal land declined by 50 percent from 1989 to 1993.
A3Fishing
The U.S. waters off the coast of North America provide a rich marine harvest, which is about evenly split in commercial value between fish and shellfish. Humans consume approximately 80 percent of the catch as food. The remaining 20 percent goes into the manufacturing of products such as fish oil, fertilizers, and animal food.
In 1997 the United States had a commercial fish catch of 5.4 million metric tons. The value of the catch was an estimated $3.1 billion in 1998. In most years, the United States ranks fifth among the nations of the world in weight of total catch, behind China, Peru, Chile, and Japan.
Marine species dominate U.S. commercial catches, with freshwater fish representing only a small portion of the total catch. Shellfish account for only one-sixth of the weight of the total catch but nearly one-half of the value; finfish represent the remaining share of weight and value. Alaskan pollock and menhaden, a species used in the manufacture of oil and fertilizer, are the largest catches by tonnage. The most valuable seafood harvests are crabs, salmon, and shrimp, each representing about one-sixth of the total value. Other important species include lobsters, clams, flounders, scallops, Pacific cod, and oysters.
Alaska leads all states in both volume and value of the catch; important species caught off Alaskas coast include pollock and salmon. Other leading fishing states, ranked by value, are Louisiana, Massachusetts, Texas, Maine, California, Florida, Washington, and Virginia. Important species caught in the New England region include lobsters, scallops, clams, oysters, and cod; in the Chesapeake Bay, crabs; and in the Gulf of Mexico, menhaden and shrimp.
Much of the annual U.S. tonnage of commercial freshwater fish comes from aquatic farms. The most important species raised on farms are catfish, trout, salmon, oysters, and crawfish. The total annual output of private catfish and trout farms in the mid-1990s was 235,800 metric tons, valued at more than $380 million. In the 1970s catfish farming became important in states along the lower Mississippi River. Mississippi leads all states in the production of catfish on farms.
A4Mining
As a country of continental proportions, the United States has within its borders substantial mineral deposits. America leads the world in the production of phosphate, an important ingredient in fertilizers, and ranks second in gold, silver, copper, lead, natural gas, and coal. Petroleum production is third in the world, after Russia and Saudi Arabia.
Mining contributes 1.5 percent of annual GDP and employs 0.5 percent of all U.S. workers. Although mining accounts for only a small share of the nations economic output, it was historically essential to U.S. industrial development and remains important today. Coal and iron ore are the basis for the steel industry, which fabricates components for manufactured items such as automobiles, appliances, machinery, and other basic products. Petroleum is refined into gasoline, heating oil, and the petrochemicals used to make plastics, paint, pharmaceuticals, and synthetic fibers.
The nations three chief mineral products are fuels. In order of value, they are natural gas, petroleum, and coal. In 1996 the United States produced 23 percent of the worlds natural gas, 21 percent of its coal, and 13 percent of its crude oil. From 1990 to 1995, as the inflation-adjusted prices for these products declined, the extraction of these fossil fuels declined, increasing U.S. dependence on foreign sources of oil and natural gas.
The United States contains huge fields of natural gas and oil. These fields are scattered across the country, with concentrations in the midcontinent fields of Texas and Oklahoma, the Gulf Coast region of Texas and Louisiana, and the North Slope of Alaska. Texas and Louisiana account for almost 60 percent of the countrys natural gas production. Today, oil and natural gas are pumped to the surface, then sent by pipeline to refineries located in all parts of the nation. Offshore deposits account for 13 percent of total production. Coal production, important for industry and for the generation of electric power, comes primarily from Wyoming (29 percent of U.S. production in 1997), West Virginia (18 percent), and Kentucky (16 percent).
Important metals mined in the United States include gold, copper, iron ore, zinc, magnesium, lead, and silver. Iron ore is found mainly in Minnesota, and to a lesser degree in northern Michigan. The ore consists of low-grade taconite; U.S. deposits of high-grade ores, such as hematite, magnetite, and limonite, have been consumed. Leading industrial minerals include materials used in constructionmainly clays, lime, salt, phosphate rock, boron, and potassium salts. The United States also produces large percentages of the worlds output for a number of important minerals. In 1997 the United States produced 42 percent of the worlds molybdenum, 34 percent of its phosphate rock, 22 percent of its elemental sulfur, 17 percent of its copper, and 16 percent of its lead. Major deposits of many of these minerals are found in the western states.
BManufacturing and Energy Sector B1Manufacturing
The United States leads all nations in the value of its yearly manufacturing output. Manufacturing employs about one-sixth of the nations workers and accounts for 17 percent of annual GDP. In 1996 the total value added by manufacturing was $1.8 trillion. Value added is the price of finished goods minus the cost of the materials used to make them. Although manufacturing remains a key component of the U.S. economy, it has declined in relative importance since the late 1960s. From 1970 to 1995 the number of employees in manufacturing declined slightly from 20.7 million to 20.5 million, while the total U.S. labor force grew by more than 46.2 million people.
One of the most important changes in the pattern of U.S. industry in recent decades has been the growth of manufacturing in regions outside the Northeast and North Central regions. The nations industrial core first developed in the Northeast. This area still has the greatest number of industrial firms, but its share of these firms is smaller than in the past. In 1947 about 75 percent of the nations manufacturing employees lived in the 21 Northeast and Midwest states that extend from New England to Kansas. By the early 1990s, however, only about one-half of manufacturing employees resided in the same region. Since 1947, the Souths share of the nations manufacturing workers increased from 19 to 32 percent, and the Wests share grew from 7 to 18 percent.
In the North, manufacturing is centered in the Middle Atlantic and East North Central states, which accounted for 38 percent of the value added by all manufacturing in the United States in 1996. Located in this area are five of the top seven manufacturing statesaNew York, Ohio, Illinois, Pennsylvania, and Michiganwhich together were responsible for approximately 27 percent of the value added by manufacturing in all states. Important products in this region include motor vehicles, fabricated metal products, and industrial equipment. New York, New Jersey, and Pennsylvania specialize in the production of machinery and chemicals. This area bore the brunt of the decline in manufacturings value of national output, losing a total of 800,000 jobs from the early 1980s to the early 1990s.
In the South the greatest gains in manufacturing have been in Texas. The most phenomenal growth in the West has been in California, which in the late 1990s was the leading manufacturing state, accounting for more than one-tenth of the annual value added by U.S. manufacturing. California dominates the Pacific region, which specializes in the production of transportation equipment, food products, and electrical and electronic equipment.
B1aInternational Manufacturing
United States industry has become much more international in recent years. Most major industries are multinational, which means that they not only market products in foreign countries but maintain production facilities and administrative headquarters in other nations. In the late 1990s, giant U.S. corporations began a wave of international partnerships, with U.S. companies sometimes merging with foreign companies.
Beginning in the early 1980s, U.S. companies increasingly produced component parts and even finished goods in foreign countries. The practice of a company sending work to outside factories to reduce production costs i