Páginas: 13 (3179 palavras) Publicado: 1 de abril de 2013
|  The richest and most diverse region on Earth, the Tropical Andes region contains about a sixth of all plant life in less than 1 percent of the world’s land area. One of the more unique plant species is an Andean bromelilad that require 100 years to mature.The threatened yellow-eared parrot, yellow-tailed woolly monkey and spectacled bear are all endemic to the Tropical Andes. Thishotspot also maintains the largest variety of amphibians in the world, with 664 distinct species. Unfortunately, almost 450 amphibian species are listed as threatened on the 2004 IUCN Red List.Although a quarter of its habitat still remains, the region is facing a variety of threats including mining, timber extraction, oil exploration, and narcotics plantations, which are all expanding due to thecontinual growth of many large cities in the region. The cloud forests are facing increased pressure from hydroelectric dams, and invasive species like the American bullfrog and grasses for cattle grazing are becoming problems as well. |

Hotspot Original Extent (km 2) | 1,542,644 |
Hotspot Vegetation Remaining (km 2) | 385,661 |
Endemic Plant Species | 15,000 |
Endemic Threatened Birds | 110|
Endemic Threatened Mammals | 14 |
Endemic Threatened Amphibians | 363 |
Extinct Species† | 2 |
Human Population Density (people/km 2) | 37 |
Area Protected (km 2) | 246,871 |
Area Protected (km 2) in Categories I-IV* | 121,650 |
†Recorded extinctions since 1500. *Categories I-IV afford higher levels of protection.
The richest and most diverse region on Earth, the TropicalAndes spans 1,542,644 km², from western Venezuela to northern Chile and Argentina, and includes large portions of Colombia, Ecuador, Peru, and Bolivia. Roughly bounded by the Tropic of Capricorn in the south and the end of the Andes range in Colombia and Venezuela in the north, the region follows the tropical portion of the Andes Mountains and several adjoining cordilleras. The Tropical Andeshotspot extends downward to an elevation of 1,000 meters in the west, where it borders the Tumbes-Chocó-Magdalena Hotspot. In the east, the hotspot reaches down to 500 meters in elevation, a cutoff between the forests of the Andean slopes and the Amazonian lowlands.
The great highs and lows of the Andes mountain range, with its snowcapped peaks, steep slopes, deep canyons, and isolated valleys, haveled to the evolution of an amazing diversity of microhabitats and species. The Tropical Andes Hotspot contains the deepest gorge in the world -- the 3,223-meter deep Cañón del Colca near Cabanaconde, Peru. The Andes also hold the highest large navigable lake in the world, Lake Titicaca, which sits at 3,810 meters on the Altiplano between Peru and Bolivia.
The Tropical Andes are sometimes splitinto northern and southern zones, divided by an arid, east-west valley that runs roughly along the Ecuador-Peru border in the far northern portion of Peru. In this valley, which is called the Marañon Gap or Huancabamba Depression, altitudes drop to about 500 meters, creating an important barrier to faunal and floral dispersal in the region. In the north, the hotspot is naturally more complex andfragmented, with the main Andean chain dividing into three cordilleras in Colombia, including the isolated Sierra Nevada de Santa Marta (Colombia’s tallest mountain). In Venezuela, the Andes terminate with the Cordillera de la Costa, Cordillera de Caripe and Península de Paria in Venezuela.
Within the hotspot, different types of vegetation correspond to gradients in altitude. Tropical wet and moistforests occur between 500 and 1,500 meters. Various types of cloud forests extend from 800 to 3,500 meters, including the montane cloud forests (yungas, ceja de selva, or ceja de la montaña) that cover more than 500,000 km² in Peru and Bolivia and are among the richest and most diverse forests on Earth. At higher altitudes (3,000-4,800 meters), grassland and scrubland systems reach up to the...
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