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LAND AND RESOURCES The total land area of Colombia is 1,141,748 sq km (440,831 sq mi). The Andes mountains dominate the central and western parts of the country, extending north-south almost the entire length of Colombia. The western two-fifths of the country lies in the highlands of the Andes. Here, towering mountain ranges are separated by high plateaus and fertile valleys that are traversed by the principal rivers of the country. Almost all of Colombia’s population lives in the narrow valleys and basins nestled among the mountains. East of the Andes, three-fifths of the country consists of portions of the llanos, or grasslands, and selva, or rain forest. The llanos lie on the plain that drains northeast into the Orinoco River, and the selva drains southeast into the Amazon River basin. Along the shore of the Caribbean Sea lies a strip of lowland.
The Andes comprise
three principal and parallel ranges: the Cordillera Occidental
in the west, the Cordillera Central, and the Cordillera Oriental
in the east. An isolated mountain mass known as the Sierra Nevada
de Santa Marta rises on the Caribbean coast; this mass includes
Colombia’s highest point at Pico Cristóbal Colón
(5,776 m/18,950 ft).
The Cordillera Central contains the volcanic peaks of Huila (5,750 m/18,865 ft) and Tolima (5,616 m/18,425 ft). About 240 km (about 150 mi) south of the Caribbean Sea, the Cordillera Central descends to marshy jungle. The cordillera peaks are perpetually covered with snow; the timberline in these mountains lies at about 3,000 m (about 10,000 ft). To the east, the Cordillera Oriental rises to a height of 5,500 m (18,000 ft). Unlike the other two ranges, the Cordillera Oriental is densely populated. Most of its inhabitants live in a series of basins in the mountains at an elevation of 2,400 m to 2,700 m (8,000 ft to 9,000 ft). The three largest cities in this region, each occupying a different basin, are Bogotá, Chiquinquirá, and Sogamoso. East of the Cordillera Oriental are vast reaches of torrid lowlands, thinly populated and only partly explored. The southern portion of this region, composed of selvas, is thickly forested and drained by the Caquetá River and other tributaries of the Amazon. The northern and greater part of the region comprises vast plains, or llanos, and is traversed by the Meta River and other tributaries of the Orinoco River.
The principal river of Colombia, the Magdalena, flows north between the Cordillera Oriental and the Cordillera Central. Crossing practically the entire country, it empties into the Caribbean Sea near Barranquilla after a course of about 1,540 km (about 957 mi). The Cauca, also an important means of passage, flows north between the Cordillera Central and the Cordillera Occidental, merging with the Magdalena about 320 km (about 200 mi) from the Caribbean Sea. In the west the Patía cuts its way through the Andes, emptying into the Pacific. The coastline of Colombia extends for about 1,760 km (about 1,090 mi) along the Caribbean and for about 1,450 km (about 900 mi) along the Pacific. River mouths along the coasts are numerous, but no good natural harbors exist.
Colombia lies
almost entirely in what is known as the Torrid Zone, the area
of the earth’s surface between the Tropic of Cancer and the
Tropic of Capricorn. The climate, however, varies with elevation.
The low regions along the coast and the deep Patía and
Magdalena river valleys are extremely hot, with average annual
temperatures of 24° to 27°C (75° to 81°F). From
about 500 to 2,300 m (about 1,500 to 7,500 ft) the climate is
subtropical, and from about 2,300 to 3,000 m (about 7,500 to 10,000
ft) it is temperate. Above about 3,000 m (about 10,000 ft) is
the cold-climate zone, where temperatures range from -18°
to 13°C (0° to 55°F). Seasonal variations are slight.
About half of Colombia’s land is forested. To the north and west of the Andes, tropical forests line the major rivers and fringe the coastal areas. East of the Andes, the forests become denser as they approach the Orinoco and Amazon rivers. Pastureland occupies about 40 percent of the country and is mostly located in the basins between the Andean highlands. Cropland accounts for a mere 4.1 percent of the land, with no more than 1.7 percent supporting permanent crops. Most of the arable land is found in patches on the Andean mountainsides. The mineral resources of the country are varied and extensive. Colombia ranks as the world’s major source of emeralds, most of which are mined in the western department of Boyacá. Other significant reserves include petroleum and natural gas, located mostly in the northeast. Most coal deposits are located on the Guajira peninsula on the country’s northeast coast. Gold and silver are found dispersed in veins throughout the central highlands. Iron ore, salt, platinum, and uranium are other important natural resources of Colombia.
Among the nations of the world, only Brazil exhibits greater biological diversity than Colombia. The country is home to one of the world’s greatest varieties of birds, as well as hundreds of different kinds of mammals and thousands of types of insects and plants. Yet the varied ecosystems of Colombia’s Andean ridges and valleys are becoming increasingly endangered, due mainly to deforestation. The indigenous flora of Colombia is as varied as the topography. Mangroves and coconut palms grow along the Caribbean coast, and the forest regions, which cover about one-half of the country, include commercially useful trees such as mahogany, lignum vitae, oak, walnut, cedar, pine, and several varieties of balsam. Tropical plants that grow in Colombia also yield rubber, chicle (see Gum), cinchona, vanilla, sarsaparilla, ginger, gum copal (see Resins), ipecac, tonka beans, and castor beans. The wildlife of Colombia includes the larger South American mammals, such as jaguars, pumas, tapirs, peccaries, anteaters, sloths, armadillos, and several species of monkeys. Caimans, once numerous along the principal rivers, have become scarce due to intensive hunting. Many varieties of snakes inhabit the tropical regions of Colombia. Birds include condors, vultures, toucans, parrots, cockatoos, cranes, storks, and hummingbirds. Increasing deforestation during the latter 20th century had negative impacts on many bird species that thrived in the rain forests of the northern Andes a century ago. For example, the yellow-eared parrot now ranks among the world’s most critically endangered species. Other endangered animals include the giant armadillo, the cotton-top marmoset, the white-footed tamarin, the tapir, the condor, and the caiman. Another threat to Colombia’s plants and animals is the smuggling of endangered species out of the country. Birds such as parrots, toucans, and macaws, and mammals including the golden lion tamarin, marmosets, ocelots, and margay cats fall victim to such illegal international trafficking. Animals are often flown out of Colombia on the same clandestine flights used for smuggling drugs.
Colombia contains several fertile low-lying valleys, but only 4.1 percent of the country’s land area, chiefly at higher elevations, is cultivated. The country’s agricultural regions suffer from soil exhaustion and erosion. These problems stem largely from slash-and-burn farming methods, in which forestland is cleared by cutting down and burning the existing plants. |
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