...the estern portion of the continent, forests are primarily associated ith mountain ranges, and coniferous trees are dominant. In California, the redood and giant sequoia gro to enormous size. A great mixture of species characterizes the tropical forests of Mexico.The vegetation cover in the drier parts of the continent is made up mainly of grassland and shrubland. The central plains and prairies of the United States and southern Canada ere originally grass covered, but much of the natural flora has been replaced by commercial crops. The dry lands of the estern United States and northern Mexico are sparsely covered ith a variety of shrubs and many kinds of cactus. Beyond the tree line in the far north is a region of tundra, containing a mixture of lo-groing sedges, grasses, mosses, and lichens.Animal Life The native ildlife of North America as once numerous and diverse, but the spread of human settlement has resulted in contracting habitats and diminishing numbers. In general, the fauna of North America is similar to that of the northern areas of Europe and Asia. Notable large mammals include several kinds of bear, the largest being the grizzly bighorn sheep bison, no only in protected herds caribou moose, called elk in Europe musk-ox and apiti. Large carnivores include the puma and, in southernmost regions, the jaguar the olf and its smaller relative, the coyote and, in the far north, the polar bear. One species of marsupial, the common opossum, is indigenous to the continent. A fe of the many reptiles are poisonous, including the coral snake, pit vipers such as the rattlesnake and copperhead, and the Gila monster and beaded lizard of the southestern United States and Mexico, the only poisonous lizards in the orld. A great variety of finfish and shellfish live in the marine aters off North America, and many kinds of fish are found in its freshater rivers and lakes.Mineral Resources North America has large deposits of many important minerals. Petroleum and natural gas are found in great quantity in northern Alaska, estern Canada, the southern and estern conterminous United States, and eastern Mexico huge beds of coal are in eastern and estern Canada and the United States and great iron-ore deposits are in eastern Canada, the northern United States, and central Mexico. Canada also has major deposits of copper, nickel, uranium, zinc, asbestos, and potash the United States contains great amounts of copper, molybdenum, nickel, phosphate rock, and uranium and Mexico has large reserves of barite, copper, fluorite, lead, zinc, manganese, and sulfur. All three countries have significant deposits of gold and silver.Agriculture Farming is relatively more important in Mexico than in the other North American countries and provides employment for about 25 percent of the labor force compared ith some 3 percent in the United States and 5 percent in Canada. Subsistence farming is still important throughout Mexico, especially in the south commercial agriculture is ell developed in many areas, hoever, particularly in the central plateau and in the north. The leading commodities are corn, heat, and beans, hich are raised mostly for domestic consumption, and cotton, cattle, coffee, and sugar, hich are produced largely for export.Agriculture in the United States and Canada is dominated by highly mechanized farms, hich produce immense quantities of crops, livestock, and livestock products. The Great Plains of the central United States and the Canadian Prairie provinces Alberta, Manitoba, Saskatchean are major orld producers of grain particularly heat, but also barley, oats, rye, and grain sorghum, oilseeds, and livestock dairy and beef cattle and sheep. Perhaps the orlds finest large farming area is the Corn Belt, that part of the U.S. Middle est from estern Ohio to eastern Nebraska, hich is the orlds largest producer of corn, as ell as a major supplier of other grains, soybeans, cattle, and hogs. Farming in California yields a huge amount of high-value irrigated crops, notably fruits and vegetables. Florida and Texas also are great producers of fruits and vegetables, and potatoes are gron in vast quantities in Idaho, ashington State, Oregon, Maine, North Dakota, and southeastern Canada. Other outstanding agricultural products include cotton, broiler chickens, dairy products, and sugarcane.Forestry and Fishing Forestry is an important sector of the Canadian economy, especially in British Columbia, Ontario, and Qubec Province. Notable forest-products industries also flourish in the estern United States particularly in ashington, Oregon, and California and in the southeastern United States.Fishing is the leading economic activity in Greenland but is a relatively unimportant sector in Canada, the United States, and Mexico, even though the catch is large and some coastal areas are dependent on revenues from sales of finfish and shellfish. Besides the aters near Greenland, major fishing grounds are off the northern Pacific coast, off the northern Atlantic coast, and off the southern Atlantic and Gulf of Mexico coasts. In addition, large tuna fleets are based in southern California and estern Mexico.Mining The extraction of minerals is an increasingly important economic activity in the United States, Canada, and Mexico. The United States has been one of the orlds leading petroleum producers for many years, Canada has been a major producer since the late 1940s, and Mexico became a orld leader in oil production in the late 1970s. The United States ranks second among orld natural-gas producers and is also a leader in mining coal, produced particularly in the vast Appalachian fields. Iron ore has long been a major product of both the United States and Canada, primarily from deposits around the estern end of Lake Superior. More recently, much iron ore has been produced in the Qubec Province-Labrador border area of eastern Canada. Among the other minerals that have been recovered in quantity in North America are copper, silver, lead, zinc, nickel, sulfur, asbestos, uranium, phosphate rock, and potash.CNOiQRSIJ239AB!!i5tBCJ OJaQJaaJ phCJ5BOJaQJataJ phBCJOJaQJaaJph5BCJOJaQJataJphCi3!!aad78Hsaa! 1h à!ia8i8NormalCJsHaJmHsHtHAiDefault Paragraph FontCai3i0i0i0i0i0i0i0i0i0i00!!!aDVDBEtioitreferat
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