Encyclopedia of Global Resources part 23 pdf

10 298 0
Encyclopedia of Global Resources part 23 pdf

Đang tải... (xem toàn văn)

Thông tin tài liệu

Web Site University of Illinois, Urbana-Champaign, Department of Materials Science and Engineering Ceramics http://matse1.mse.uiuc.edu/ceramics/ ceramics.html See also: Abrasives; Clays; Glass; Mica; Quartz; Sand and gravel; Silicates; Silicon. Cesium Category: Mineral and other nonliving resources Where Found The element cesium makes up only 7 parts per million of the Earth’s crust. Found only in minerals, it does not occur in its free state naturally. The leading pro- ducers are in southwest Africa, the Russian republics, Sweden, and the island of Elba. In North America it is most often foundin ores in South Dakota, Maine, and Manitoba, Canada. Significant reserve bases exist in Namibia and Zimbabwe as well as Canada. Primary Uses Cesium has significant applications in the manufac- ture of photoelectric cells and vacuum tubes. One of its isotopes, cesium 137, is used in radiation therapy. Cesium compounds have also served as antishock agents after administration of arsenic drugs. The In- ternational Atomic Energy Agency has also identified cesium 137 as one of the radioactive materials that may be used to make “dirty bombs.” Technical Definition Cesium (abbreviated Cs), atomic number 55, belongs to Group I of the periodic table of the elements and is the heaviest of the alkali metals (excluding the radio- active francium). It has twenty-two known isotopes, with masses ranging from cesium 123 to cesium 144, with an average atomic weight of 132.905. The only naturally occurring isotope is cesium 133. Description, Distribution, and Forms Pure cesium is a silver-white, ductile metal that is ex - tremely malleable. Finely divided cesium produces a blue flame and is easily oxidized by burning brightly in humid air; it may explode in the presence of water. It has a density of 1.9 grams per cubic centimeter, a melting point of 28.5° Celsius, and a boiling point of 705° Celsius. History Cesium was discovered and detected by spectroscopy in 1860 by the German scientists Robert Bunsen and Gustav Robert Kirchhoff, who during their analysis detected the two blue lines of cesium and named the element after the word caesius, Latin for “sky blue.” The metal was first isolated by electrolysis in 1881. Ce- sium compounds are widely distributed in nature in small quantities in various ores. The greatest sources of cesium are the silicate mineral pollucite, which contains up to 34 percent cesium oxide, and camal- lite. Only 0.002 partper million of cesium exist,insea- water. Detectable quantities are found in plant and animal organisms, mineral waters, and soils. Cesium in conjunction with rubidium and lithium is found in several lepidolite oresinZimbabweandSouthAfrica. Obtaining Cesium Cesium is obtained by applying the so-called lime- stone process to lepidolite ore. After treatment of the ore with limestone (known as carbonation), lithium is separated, cesium carbonate is reduced by metallic magnesium, and cesium metal is isolated by conden- sation of its vapors. Another process for obtaining cesium first produces cesium chloride, which upon heating with a reducing element such as calcium or lithium yields the pure metal. Cesium’s low electro- negativity is responsible for its vigorous reaction with oxidizing agents. It reacts readily with most ordinary compounds, such as the halogens, ammonia, nitro- gen, carbon monoxide, andevenorganic compounds such as ethylene and acetylene. Uses of Cesium Cesium metal is used in photoelectric cells and in the optical and detecting devices of many analytical in- struments. Cesium compounds are used in glass and ceramic production plants, and cesium chloride is used to remove small quantities of oxygen and water during the manufacture ofvacuumtubes. Cesium 137 is often used in radiation therapy treatments. Some of the isotopes of cesium are toxic. Cesium 137 is aradioactivebeta-emitter whose ions migrateto the same places in the body that sodium ions go. One of theworst radiation accidents in history occurred in 190 • Cesium Global Resources Goiânia, Brazil, in 1987. An abandoned radiotherapy clinic was visited by scavenging inhabitants of the area. They discovered a cesium 137 machine and opened the tube, thus exposing themselves to the harmful rays. Several people died, and about 250 more were contaminated. In February, 2008, the Na- tional Research Council mandated the U.S. govern- ment to seek alternatives to replace cesium 137. Soraya Ghayourmanesh Web Site WebElements Caesium: The Essentials http://www.webelements.com/caesium/ See also: Arsenic; Isotopes,radioactive; Lithium; Nu- clear energy; Nuclear waste and its disposal. Chernobyl nuclear accident Category: Historical events and movements The 1986 meltdown of the nuclear reactor at the Cher- nobyl nuclear plant in Ukraine was the most danger- ous nuclear accident of the twentieth century, killing hundreds and not only compromising the long-term health of many human beings but also killing or poi- soning animals, crops, and economic resources. Definition On April 26, 1986, an accident at the Chernobyl nu- clear plant in Ukraine dispersed radioactive material over much of Europe, killing several hundred people at or near the reactor and contaminating crops and animals as far away as northern Scandinavia. Overview Nuclear reactors produce electricity using steam pro- duced from the heatgivenoff in nucleardecaytoturn turbines that generate electricity. In late April of 1986, operators at reactor number four of the Chernobyl nuclear plant undertook a testto determine how long the plant’s turbines couldproduce electric powerand operate the plant’s safety systems after the steam was shut off. The operators made a series of errors that al- lowed the cooling water to drop below the critical level. Since the emergency cooling system had previ - ously been shut down, it did not respond to the low water level, and the temperature of the core increased. At 1:23 a.m. onApril26, the remaining water in there- actor core—where the uranium fuel decays, generat- ing heat—expanded rapidly, producing steam. The resulting explosion destroyed the core and part of the building. A fireball appeared, and burning lumps of graphite and reactor fuel were dispersed around the site, starting fires that carried more radioactive mate- rial into the air. Radiation poisoning resulted in the hospitalization of approximately two hundred plant workers and firefighters within thirty-six hours of the explosion. Everyone within10 kilometers of theplant,except for crews still trying to contain the radiation release, was evacuated by the evening of April 26. On May 2 this evacuation zone was expanded to 30 kilometers. More than 100,000 people were eventually moved from the danger area. A cloud containing radioactive material was car- ried awayfrom the siteby the wind. In theareas where it was raining when the cloud passed overhead, high concentrations of radioactive material accumulated on the ground. Poland, Hungary, and the Soviet Union restricted grazing by cattle, and most of the strawberry crop in Austria was discarded because of radioactive contamination. Significant levels of radia- tion spread as far as Sweden. Contamination near Gävle, about 240 kilometers north of Stockholm, re- quired that 1,000 square kilometers of grass be burned. In Lapland, in northern Scandinavia, meat from fifty thousand reindeer had to be discarded. By 1989, about 250 persons who worked at the Chernobyl plantorassistedin the cleanup had diedas a result of radiation exposure. The long-term effects of the radiation release remained less certain. Ukrai- nian officials estimated that the Chernobyl accident would eventually be responsible for six thousand to eight thousand deaths. The British National Radio- logical Protection Board estimated that about one thousand people inWestern Europe would eventually die of cancers induced by the Chernobyl radiation. Public confidence in the safety of nuclear reactors was shaken by the Chernobylaccident(and by the ear- lier, far less serious accident at Three Mile Island in Pennsylvania). Groups opposed to the nuclear indus- try gained strength, forcing the abandonment of the Shoreham reactor on Long Island, New York, and speeding up plans by the Swedish government to close all commercial reactors in that country. George J. Flynn Global Resources Chernobyl nuclear accident • 191 See also: Health, resource exploitation and; Nuclear energy; Nuclear Regulatory Commission; Three Mile Island nuclear accident; Uranium. Chile Categories: Countries; government and resources Chile is the world’s leading producer of copper, which accounts for most of the total value of the nation’s ex- ports. Other primary resources that are the bases for ex- ports include evaporites, containing several important trace minerals (iodine, lithium, and boron); marine resources for fish and fish products; agricultural land for growing fruits (especially grapes) and nuts; and forestland for wood, paper, and paper products. The Country Chile is on the southwestern margin of South Amer- ica. The Pacific Ocean lies to the west, and Argentina and Bolivia are to the east. The country’s territory runs north to south for approximately 4,400 kilome- ters. Its greatest width is barely 160 kilometers. The Atacama Desert in the north is one of the world’s dri- est. The Andes Mountains extend the length of the country and form a natural barrier between Argen- tina and Bolivia. Chile is slightly smaller than Texas. Geology, climate, and nutrient-rich coastal waters are the bases for a wealth of primary resources, but mining dominates Chile’s economy. It is the world’s leading producer of copper, a metal of vital impor- tance to the global economy for its use in coins, wir- ing, and construction. Chile has three distinct eco- nomic regions—the north, the south, and the middle—that contribute to the export-based econ- omy. The north is one of the world’s main sources of copper and related metals. The relatively high con- tent of iodine, lithium, and boron mined from the salars (salt flats) of the north has global significance. The south contributes fish and timber products. The middle exports fruits, vegetables, fish, and copper. Chile had the world’s forty-fifth largest economy in 2008. Copper Ore Chile produces about 35 percent of the world’s cop - per and possesses about 30 percent of theworld’s total identified copper-ore reserves. In 2006, the value of copper mine production was $31.5 billion, which rep - resented about 22 percent of the country’s gross do- mestic product. Six of the ten largest copper mines in the world are in Chile; four of the ten are in northern Chile. In that region, broad, open-pit mines operate along the western edge of the Andes Mountains, be- cause the ore deposits are in geologic faults near the surface. The region includes the Escondida mine,the world’s largest open-pit copper mine. The mine be- gan operating in 1990 and accounts for nearly 25 per- cent of Chile’s total production. An international consortium (Australia, the United Kingdom, and Ja- pan) operates the mine. The government operates the Chuquicamata mine, which is the world’s second largest copper mine. The deposits of copper in mid- dle Chile are also in the Andes, but they are so deep underground that they require tunneling to extract the ore, which is more expensive than open-pit min- ing. Nevertheless, there are seven Andean copper mines in the region; two of them, the El Teniente and Andina mines,are among the world’s top-ten produc- ers. El Teniente holds the distinction as the world’s longest underground mine. Chile used to simply mine the copper ore, crush it, and then export it to other countries for processing. However, beginning in the early 1990’s, direct invest- ments by foreign companies helped upgrade the na- tion’s copper mills to include the process of smelting, which involves melting the ore to remove nonmetal impurities. Shipping the resulting concentrate saves money by reducing transportation costs. The country that imports the copper concentrate finishes the re- fining process by melting it into copper slabs. The leading importers ofChilean copper have been China, Japan, and the United States. Chilean companies are not likely to build their own refineries, as the high costs of importing fossil fuels to generate electricity make installing additional refining capacity less prof- itable than continuing to ship ores and concentrates abroad. The government could increase thereservoir capacity of hydroelectric dams in the Andes Moun- tains in order to help fillthe shortfall in energy needs. However, it has been reluctant to do so because the dams are in environmentally sensitive areas. Iodine The origin of iodine is a mystery, but it is believed to have come from organic films on the sea surface or from gases and sublimates associated with Andean vol - canism. Either way, the iodine is believed to have en - 192 • Chile Global Resources Global Resources Chile • 193 Chile: Resources at a Glance Official name: Republic of Chile Government: Republic Capital city: Santiago Area: 291,954 mi 2 ; 756,102 km 2 Population (2009 est.): 16,601,707 Language: Spanish Monetary unit: Chilean peso (CLP) Economic summary: GDP composition by sector (2008 est.): agriculture, 4.8%; industry, 50.5%; services, 44.7% Natural resources: copper, timber, iron ore, nitrates, precious metals, molybdenum, hydropower Land use (2005): arable land, 2.62%; permanent crops, 0.43%; other, 96.95% Industries: copper, other minerals, foodstuffs, fish processing, iron and steel, wood and wood products, transport equipment, cement, textiles Agricultural products: grapes, apples, pears, onions, wheat, corn, oats, peaches, garlic, asparagus, beans, beef, poultry, wool, fish, timber Exports (2008 est.): $66.46 billion Commodities exported: copper, fruit, fish products, paper and pulp, chemicals, iodine, lithium, boron, wine Imports (2008 est.): $57.61 billion Commodities imported: petroleum and petroleum products, chemicals, electrical and telecommunications equipment, industrial machinery, vehicles, natural gas Labor force (2008 est.): 7.267 million Labor force by occupation (2005): agriculture, 13.2%; industry, 23%; services, 63.9% Energy resources: Electricity production (2006 est.): 50.37 billion kWh Electricity consumption (2006 est.): 45.52 billion kWh Electricity exports (2007 est.): 0 kWh Electricity imports (2007 est.): 1.628 billion kWh Natural gas production (2007 est.): 1.8 billion m 3 Natural gas consumption (2007 est.): 4.2 billion m 3 Natural gas exports (2007 est.): 0 m 3 Natural gas imports (2007 est.): 2.4 billion m 3 Natural gas proved reserves ( Jan. 2008 est.): 97.97 billion m 3 Oil production (2007 est.): 11,610 bbl/day Oil imports (2006 est.): 222,900 bbl/day Oil proved reserves ( Jan. 2008 est.): 150 million bbl Source: Data from The World Factbook 2009. Washington, D.C.: Central Intelligence Agency, 2009. Notes: Data are the most recent tracked by the CIA. Values are given in U.S. dollars. Abbreviations: bbl/day = barrels per day; GDP = gross domestic product; km 2 = square kilometers; kWh = kilowatt-hours; m 3 = cubic meters; mi 2 = square miles. Santiago Chile Bolivia Peru Argentina Atlantic Ocean Pacific Ocean tered the atmosphere, and then surface and ground - water absorbed and transported it into the northern Chile’s Atacama Desert, where it was oxidized to io- date and mineralized with nitrates in the caliche de- posits. At first, Chile’s iodine production was a by- product of the production of sodium nitrate fertilizer from the caliche deposits. Now, however, it is extracted from abandoned nitrate ores and tailings that remain from earlier nitrate mining. The caliche ores and tail- ings are mainly in the northern sectionofChile’s Cen- tral Valley, in Tarapacá and Antofagasta Provinces. The crushedcalicheandtailingsareleachedinevapo- ration ponds to produce a solution containing so- dium nitrate and calcium iodate. After the sodium ni- trate precipitates in theponds,the remaining liquid is stripped of iodine. About 60 percent of global re- serves of iodine are in northern Chile. Chile accounts for 60 percent of the global production, making it the world’s leading exporter of themineral. Japan is a dis- tant second, followed by China. Chile’s production of iodine is significant, because iodine deficiency causes an increase in child mortality, mental retardation, and miscarriages. Some governments now require food manufacturers to include iodine in certain food products as a means of preventing maladies associ- ated with iodine deficiency. Lithium Most of the world’s lithium is mined in Chile. Lithium is a rare metallic element that is concentrated natu- rally in two main settings. It mineralizes in an igneous environment during the formation of silicic and peg- matite rocks and it appears in salt compounds as lith- ium carbonate and lithium chloride in dry lake beds of deserts. Thus, mining lithium involves hard-rock mining or salt-mining in ancient lake beds. Both forms of lithium concentration are rare geographi- cally, but the lithium in lake-bed salts (or brines) is much easier to mine. Hard-rock mining was the pri- mary source of lithium until miners discovered that certain lake beds in northern Chile had significant de- posits of the metal.ThefirstChilean mine started pro- ducing lithium in 1986. In 1997, Chile replaced hard- rock mining operations in the United States, where most of the world production of lithium was taking place, and became the world’s leading exporter of lithium. Chile provides about 40 percent of global supply, outpacing Australia, which was the second largest producer in 2008. Chile has three-fourths of the world’s reserves of lithium. The mineral is mined from the brines in salars in northern Chile’s Atacama Desert. The deposits there are in a series of basins. The Chilean company Sociedad Química y Minera (SQM) mines the Salar de Atacama, which contrib- utes more than 50 percent of the world’s lithium.The SQM operation also produces potassium sulfate as a by-product. Two processing plants in Antofagasta, a seaport in northern Chile, refine and package the lithium for shipment overseas. Among other uses, lithium has become important in the manufacture of rechargeable batteries for hybrid cars, laptop com- puters, and cell phones. Boron Chile accounts for about 10 percent of the global pro- duction of boron. In 2006, it ranked fourth in world production behind Turkey, the United States, and Argentina, indescending order. Chile’s borate depos- its are in high-desert basins in the Puna region of the Andes Mountains, which overlaps the borders of Chile, Argentina, and Bolivia. In Chile, borate depos- its are found in two formations, salar and caliche. Both formations are at about the same depth below the surface. Salar deposits are what remain after lake water evaporates. Chile has a large number of dry lake beds, but only six (Ascotan, Aguas Calientes Sur, Atacama, Quisquiro, Pajonales, and Surire) contain commercial borate. The borate is in layers that aver- age between 1 to 2 meters below the surface and range from 1 centimeter to1 meter thick. The second source of borate is caliche, a puzzling layer of so- dium nitrate in the Atacama Desert, Chile’s north- ern coastal desert. No one knows for sure how the caliche formed. The most common theory is that rocks in the moist Andes experienced underground weathering that produced nitrate salts, which con- tained borate compounds, and then groundwater seepage transported the salts to the lower valleys of the Atacama Desert. The nitrates accumulated near the surface there through a process driven by sur- face evaporation and hygroscopic and capillary activ- ity. The resulting ore grade nitrates accumulated from 1 to 5 meters below the surface in a vast, almost con- tinuous deposit that stretches north-south for 700 kilometers and east-west for a distance of 10 to 150 ki- lometers. There are two large boron mining operations in the northern desert. The largestproducer of borateis Quiborax. The company has mining operations at Salar de Surire near theBolivian border. It has smaller 194 • Chile Global Resources operations on SalarsAscotan and Pajonales, anditop - erates a boric acid plant in the northern seaport town of Antofagasta. The second company is SQM, which produces boricacid as a by-product of its lithium min- ing operation on Salar de Atacama. Chilean boric acid and other boron-based products are exported to the United States, Brazil, and several countries in Asia. In addition to boric acid, boron-based com- pounds are used in the manufacture of such items as cosmetics, soaps and detergents, flame retardants, glazes on ceramics, and fiberglass. Forests Forestry is the most important economic activity of southern Chile. Large, privately owned sawmills dot the landscape. Band saws cut straight-trunk logs of fir and araucaria pine into narrow slabs of quality lumber for export. Each mill has a wood chipper that makes chips from low-grade wood. Pulp mills turn the chips into an oatmeal-like pulp. The mills then process the pulp into paper, cardboard, and particleboard prod - ucts. The chemicalindustry also uses thepulp.Chile’s forestry industry specializes in making wood pulp; only Canada, the United States, Brazil, and Sweden produce more. Chile has been the world’s sixth larg- est exporter of wood chips, pulp, and waste paper. China and Italy are the main trading partners for the Chilean exports. In order to conserve natural forest areas, the pulp industry depends heavily on fast-growing, commer- cially planted trees, such as eucalyptus (from Austra- lia) and radiata pine (from Austria). About one-half of Chile’s pulp production comes from such trees. Southern Chile’s west coast marine climate is most conducive to the fastest tree growth, making Puerto Montt and the Chiloé Island the main pulp and lum- ber centers. Wood chips, pulp, lumber, and other wood products are the region’s most valuable export. Japan, the United States, and Germany import most of these products. Global Resources Chile • 195 A massive mining truck rolls past Chile’s Andina copper mine, one of the largest in the world. (Ivan Alvarado/Reuters/Landov) Fish The nutrient-rich waters of the Humboldt Current are the main basis of Chile’s large fishing industry. The nation ranks in the top five in the world produc- tion. Northern Chile contributes a great deal to this status. The catch includes anchovy, jack mackerel, and pilchard. Iquique, in the north, is one of the world’s principal ports for its huge fishmeal exports. Fishmeal is ground-up dried fish. Anchovies, in partic- ular,makeupthisproduct. Fishmeal is high in protein and therefore an excellent livestock food supple- ment. Fish oil, a by-product of fishmeal production, is an additive for the manufacture of many items, rang- ing from margarine to inedible varnishes and water- proofing agents. Every three to seven years, El Niño warming events cause declines in fish populations in northern Chilean coastal waters, whichhurt the econ- omy of the region. Anchovy populations, in particu- lar, decline during these events. Fishing for export is also a chief income source in southern Chile; Puerto Aisén is the area’s main fish- ing port. This region is known for its salmon farming, which involves raising salmon in enormous floating cages tied to the seabed.Beginning in 1990,fish farm- ing grew steadily and became increasingly impor- tant to Chile’s total exports. Chilean salmon has be- come known for its boneless salmon filets anddelicate smoked sliced salmon. However, the industry has been plagued by a parasitic bacterium, rickettsia, carried by sea lice, which causes infection-prone lesions. Never- theless, Chileis the second largest exporter of salmon after Norway,thankslargely to Aisén’s contribution of caught and farmed salmon. In value of exports, fish- ing ranks second behind forestry in southern Chile. Agricultural Land Due in part to a favorable environment, middle Chile is a major center for agricultural exports.Theareahas more than 50 percent of the country’s total agricul- tural landholdings. Most of the production takes place in the Central Valley section. Because of the fer- tile soils, reliable watersupply, and mild climateof the valley, the country’s annual export earnings from fruits and nuts alone are between $1 and $2 billion per year. The country consistently ranks inthe top ten for fruit exportation. Vineyards for table grapes and wine-making take up more land than any other fruit crop in the Central Valley. The production is for the international market. Each summer, the area’s table grapes, as well as strawberries and raspberries, are the first in Chile to ripen and the first to hit U.S. super - markets, usually around Christmas. The Central Val- ley is responsible for the nation’s high world ranking in exports of wine as well as table grapes. Grains are also widespread in the middle Chile region, par- ticularly wheat, which occupies more than half the cropland. Fruit trees occupy much of the remaining land. The Mediterraneanclimate of middle Chile also allows the planting of commercial orchards of apples and avocados, which are extensive in hilly sections of the region. Other tree crops includelemons,oranges, nectarines, kiwifruits, and cherries. Other Resources Chile accounts for a wide range of other industrial minerals. It accounts for approximately 7 percent of the global supply of gold, 6 percent of selenium, 3per- cent of sulfur, 2.6 percent of phosphate rock, 2.5 per- cent of silver, 2.5 percent of salt, and between 2 per- cent of both diatomite and potash. The country’s copper mines produce some of the silver, gold, sele- nium, and molybdenum, as the same geologic envi- ronment forms these minerals. Chile ranks relatively high in world production of each metal. Richard A. Crooker Further Reading Anyadike, Nnamdi. Copper: A Material for the New Mil- lennium. Cambridge, Cambridgeshire, England: Woodhead, 2002. Central Intelligence Agency. CIA Fact Book. New York: Skyhorse, 2007. Crooker, Richard A. Chile. Edgemont, Pa.: Chelsea House, 2004. Garrett, Donald E. Borates: Handbook of Deposits, Pro- cessing, Properties, and Use. San Diego, Calif.: Aca- demic Press, 1998. Kogel, Jessica Elzea, et al., eds. Industrial Minerals and Rocks: Commodities, Markets, and Uses. 7th ed. Little- ton, Colo.: U.S. SocietyforMining,Metallurgy,and Exploration, 2006. Moreno, Teresa, and Wes Gibbons, eds. The Geology of Chile. London: Geological Society of London, 2007. Neira, Eduardo, Hernán Verscheure, and Carmen Revenga. Chile’s Frontier Forests: Conserving a Global Treasure. Washington, D.C.: Global Forest Watch and World Resources Institute, 2002. Rector, John Lawrence. The History of Chile. Westport, Conn.: Greenwood Press, 2005. 196 • Chile Global Resources Web Sites Central Intelligence Agency The World Fact Book https://www.cia.gov/library/publications/the- world-factbook/index.html International Copper Study Group http://www.icsg.org/ International Trade Centre Countries http://www.intracen.org/menus/countries.htm U.S. Geological Survey Minerals Information http://minerals.usgs.gov/minerals/ See also: Agricultural products; Agriculture indus- try; Boron; Copper; Forests; Iodine; Lithium; Timber industry. China Categories: Countries; government and resources China, blessed with abundant natural resources, plays a pivotal role in the global economy and the well- being of Earth. China ranks first in both human re- sources and hydraulic-power resources. The nation’s rich human resources have resulted in the production of the most cost-effective goods, which dominate the global market. The development of its hydraulic power reserves and use of other natural resources have made China’s economy one of the top in the world. The Country China, a country that occupies a vast territory with a diverse climate, varied topography, and great variety of flora and fauna, is situated in East and Southeast Asia. Its land extends from longitude 73° east (in the west) to 135° east, a stretch of more than 5,100 kilome- ters. From north to south, it spans from latitude 53° north to 4°north, covering a distance of 5,471kilome- ters. With such a vast expanse, China is rich in land, water, climate, biological, mineral, energy, and tour- ism resources. China, with a total area of approximately 9.6 mil - lion square kilometers, ranks as the third or fourth (depending on the territory counted) largest nation in the world. About one-third of it is mountainous, with plateaus and high mountains dominating the west, whilelower lands and plains lacethe central and eastern region. As a result of this tilting topography, major rivers flow from west to east. These include the world-famous Chang (also known as Yangtze) and Huang (also known as Yellow) rivers, both of which empty into the Pacific. The vast territory, varied climate zones, and diverse topography provide suitable habitats for a rich flora and fauna. China is considered amega-diversity coun- try. Overall, an estimated thirty-two thousand species of flowering plants exist in China. More than five thousand species of vertebrates spread across the land, accounting for 11 percent of the world’s total. China is also the most populated country on Earth. Utilizing its available resources and a double-digit an- nual gross-domestic-product growth, which began in 1982, China’s economy has climbed to the thirdinthe world, closing in on Japan for second. However, that achievement comes at a price of environmental peril. Should China expect to continue growing economi- cally, sustainability has to be the focal point for the fu- ture. Arable Land Resources China ranks third among world nations in total terri- tory, behind Russia and Canada. However, because of its large population and vast mountain ranges in the north and west, China’s per capita total land resource accounts for only one-third of the world’s average. The average arable land per capita is only 0.1 hectare, ranking sixty-seventh in the world. China’s forestland averages about 0.1 hectare per capita, ranking 121st in the world. There has been a steady decline in both farm and forestland because of erosions, desertifica- tion, road construction, and urbanization. China’s land resources can be divided into many soil types: red, yellow, brown, cinnamon, black, cher- nozem, chestnut, desert, saline-alkali, marshland, mountain, and a variety of implicit domains. These varied soil typesare formed asa result of combinedef- fects by topography, climate, and human influences. The principal uses of the land resources fall into six categories: arable land, grassland, forest, alpine desert, desert, and permanentsnowandglacierarea. The 122 million hectares of arable land can be fur- ther divided into irrigated land, paddy fields, and dry land, each accounting for 22, 26, and 52 percent of the total, respectively. The arable land distribution is Global Resources China • 197 198 • China Global Resources China: Resources at a Glance Official name: People’s Republic of China Government: Communist state Capital city: Beijing Area: 3,705,677 mi 2 ; 9,596,961 km 2 Population (2009 est.): 1,338,612,968 Language: Standard Chinese or Mandarin Monetary unit: renminbi (CNY) Economic summary: GDP composition by sector (2008 est.): agriculture, 11.3%; industry, 48.6%; services, 40.1% Natural resources: coal, iron ore, petroleum, natural gas, mercury, tin, tungsten, antimony, manganese, molybdenum, vanadium, magnetite, aluminum, lead, zinc, uranium, hydropower potential (world’s largest) Land use (2005): arable land, 14.86%; permanent crops, 1.27%; other, 83.87% Industries: mining and ore processing, iron, steel, aluminum, and other metals, coal; machine building; armaments; textiles and apparel; petroleum; cement; chemicals; fertilizers; consumer products, including footwear, toys, and electronics; food processing; transportation equipment, including automobiles, rail cars and locomotives, ships, and aircraft; telecommunications equipment, commercial space launch vehicles, satellites Agricultural products: rice, wheat, potatoes, corn, peanuts, tea, millet, barley, apples, cotton, oilseed, pork, fish Exports (2008 est.): $1.435 trillion Commodities exported: electrical and other machinery, including data processing equipment, apparel, textiles, iron and steel, optical and medical equipment Imports (2008 est.): $1.074 trillion Commodities imported: electrical and other machinery, oil and mineral fuels, optical and medical equipment, metal ores, plastics, organic chemicals Labor force (2008 est.): 807.3 million Labor force by occupation (2006 est.): agriculture, 43%; industry, 25%; services, 32% Energy resources: Electricity production (2007): 3.256 trillion kWh Electricity consumption (2007): 3.271 trillion kWh Electricity exports (2007 est.): 14.56 billion kWh Electricity imports (2007 est.): 4.251 billion kWh Natural gas production (2007 est.): 69.27 billion m 3 Natural gas consumption (2007 est.): 70.51 billion m 3 Natural gas exports (2007 est.): 5.36 billion m 3 Natural gas imports (2007 est.): 3.871 billion m 3 Natural gas proved reserves ( Jan. 2008 est.): 2.265 trillion m 3 Oil production (2008 est.): 3.725 million bbl/day Oil imports (2007): 4.21 million bbl/day Oil proved reserves ( Jan. 2008 est.): 19.6 billion bbl Source: Data from The World Factbook 2009. Washington, D.C.: Central Intelligence Agency, 2009. Notes: Data are the most recent tracked by the CIA. Values are given in U.S. dollars. Abbreviations: bbl/day = barrels per day; GDP = gross domestic product; km 2 = square kilometers; kWh = kilowatt-hours; m 3 = cubic meters; mi 2 = square miles. Beijing Russia India China Kazakhstan Nepal Mongolia North Korea Japan Pakistan Pacific Ocean very uneven, mostly concentrated in areas of the North China Plain, Northeast ChinaPlain, the Chang River Plain, Sichuan basin, and the Pearl River Delta. The flat, deep soil of the North China Plain supports production of food crops, including wheat, corn, mil- let, sorghum, and cotton and fruit crops of apples, pears, and grapes. The black, fertile soil in the north- east is productive for wheat, corn, soybeans, flax, and sugar beets. The Chang River Plain and Sichuan ba- sin, known as the “land of plenty,” produce rice, cit- rus, broad beans, and freshwater fish. Other Land Resources The total area of grassland in China is about 400 mil- lion hectares, of which 225 million hectares are consid- ered usable. The grassland stretches from northeast to southwest for a span of more than 3,000 kilometers and is home to many animal husbandry bases. Nei Monggol has China’s largest pastureland, where the well-known Sanhe cattle, Sanhe horses, and Mongo- lian sheep reside. Another important natural pasture and livestock breeding and production base is situ- ated in the north andsouth of Tian Shan as well as the Xinjiang Uygur autonomous region, where the famous Ili horses and Xinjiang fine-wool sheep are raised. Forestland in China accounts for 134 million hect- ares. The per-capita forestland is only one-sixth of the world’s average. The forestland covers only 14 per- cent of total land area, much lower than the world’s average of 22 percent. Forest distribution is also un- even. Manchuria, a vast plain bracketed by two moun- tain ranges, the DaXingan Mountainsto the west and the Xiao Xingan to the east, contains China’s richest and most accessible timber resources. Coniferous trees—including spruce, pine, fir, larch, and juni- per—dominate the landscape. Broadleaf species in- clude birch, aspen, willow, and mountain ash. The second largest natural forests are found in southwest China, where the main tree species include spruce, fir, Yunnan pine, camphor, mahogany, and precious teak. Using its lumber and cheap labor, China has be- come a major exporter of furniture, plywood, doors, cabinets, and many other wood products. The alpine desert, occupying about 15 million hectares, mainly located in the northern Tibet pla- teau, supports only sporadic grazing in scattered ar- eas. Desert accounts for 64 million hectares, of which the Gobi alone takes up 46 million hectares. The cli - mate is arid, with extreme fluctuations of temperature between day and night. All plants and wildlife here are adapted to arid and harsh climate. Drought-adapted shrubs include the gray sparrow’s saltwort, gray sage- brush, saxaul, and low grasses, such as needle grass and bridle grass. Notable animals include the Asiatic wild ass, Asiatic ibex, black-tailed gazelle, wild camel, wild horses, jerboa, Gobi wolf, golden eagle, leopard, and lizards. The Gobi bear is one of the world’s most endangered animals, with a total population of less than fifty. Water Resources China is very rich in water resources. The totalwaterre- serve is about2.8 trillion cubicmeters, rankingfifth in the world, butthe per-capita average is lessthan 25 per- cent of the world’s average. In addition, the distribu- tion of the water resources is highly uneven; they are more concentrated in thesouthand east, much less in the northwest. The total length of all rivers in China is 430,000 kilometers. There are more than 50,000 rivers with a drainage area of at least 100 square kilometers each, 1,580 rivers witha drainage area of 1,000 square kilometers, and 79ofthem with drainage areas exceed- ing 10,000 square kilometers. More than 20 rivers stretch at least 1,000 kilometers, among which the Chang and Huang are the two longest. China’s river system exhibits some unique charac- teristics. Most ofthe rivers flowfrom west toeast, emp- tying into the Pacific. Only a few in the southwest flow in a north-south direction. The vast majority of the drainage areas are located in the southeast of the out- flow basin, with atotalcovered area of 612 millionhect- ares, or almost64 percent of the land. In addition,the upper reaches of many rivers run through canyons or run as mountain torrents. The steep gradient creates strong and rapid water currents, which have great hydropower potential. The middle and lower reaches of many rivers weave through vast,flat plains. The wide surface and slow flow ensure use of water resources for irrigation, fisheries, and transportation. There are about 24,900 natural lakes across China, with 13 great lakes, each covering more than 100,000 hectares of surface area. Most freshwater lakes are lo- cated in the easternregion,accounting for 45 percent of thetotal lake surface. These include the famous Bo Yang, Dongting, Hongze, Tai, and Chao. Themajority of the lagoons are distributed in the west, including the well-known Qinghai Lake. A great number of gla- ciers in western China are also major reserves for both surface and groundwater, covering an area of 5.8 mil - lion hectares. The total storage capacity is 2.7 trillion Global Resources China • 199 . the iodine is believed to have en - 192 • Chile Global Resources Global Resources Chile • 193 Chile: Resources at a Glance Official name: Republic of Chile Government: Republic Capital city: Santiago Area:. is stripped of iodine. About 60 percent of global re- serves of iodine are in northern Chile. Chile accounts for 60 percent of the global production, making it the world’s leading exporter of themineral cherries. Other Resources Chile accounts for a wide range of other industrial minerals. It accounts for approximately 7 percent of the global supply of gold, 6 percent of selenium, 3per- cent of sulfur,

Ngày đăng: 04/07/2014, 01:20

Tài liệu cùng người dùng

  • Đang cập nhật ...

Tài liệu liên quan