The alpine biome is found in various mountain regions of the world. They’re usually located at altitudes of up to 3048 meters (10,000 feet), where trees are scarce. Temperatures in the alpine tundra biome are generally below freezing in the winter, when it receives little to no sunlight, and from 10-15° C (50-59° F) during the summer, although, temperatures may vary, depending on which region of the world the alpine tundra is located. The main form of precipitation is received as snow. Alpine biomes are unique due to the severity and complexity of their environmental conditions. Alpine tundra vegetation consists mostly of small growing shrubs and some scattered trees.
Alpine tundra occurs in mountain ranges around the world, such as the American Cordillera which includes the continuous mountain ranges of North Central and South America, including Antarctica; the Himalayas in Asia; the Alps and Pyrenees in Europe; the Andes in South America; the Eastern highlands in Africa; and the central regions of Borneo and New Guinea in the Pacific Ocean. The alpine tundra in these regions lies at altitudes above 3050 meters (10,000 feet) above sea level, just below the snow line (ecotone) of a mountain. Alpine tundra turns into a subalpine forest below the tree line, which is at a lower altitude.
The alpine tundra is most commonly found on high mountain tops, mountain slopes; and mountain ridges above the subalpine zone, which is a natural boundary (ecotone) between a line of coniferous trees, such as firs and pines, and the alpine tundra biome. Most alpine landscape is uneven and rough with cliffs, talus slopes and snowcapped peaks. Rainfall in the alpine tundra, which usually runs-off the steep mountain sides, and a layer of permafrost along with prevailing strong winds, limit plant growth. The permafrost layer will defrost in the brief summer allowing plant growth. Permafrost makes it difficult for trees to grow in the alpine tundra.
The cold climate in the alpine tundra is usually cold due to low air pressure, which is characteristic of high altitudes. The alpine tundra is characterized by intense cold, wind, ice, snow and solar radiation. The average annual precipitation averages 50 cm (20 inches), and is usually as snow, often accompanied by strong dry winds. High winds along with low temperatures have made the alpine tundra inhospitable to most plants and animals found in more temperate regions. In the summer, the temperatures range from 10-15° C (50-59° F), while during the winter, temperatures may lower down the freezing point 0° C (32° F).
There are varied plant species thriving in the alpine environment, including perennial grasses, mosses, sedges, forbs, cushion plants, lichens and woody or semi-woody shrubs. Most plants grow close to the ground (low-growing plants), where sediments from the weathering rocks has deposited soils to support grasses. Alpine plants have developed methods of adaptation, such as freeze tolerance. They can also dehydrate their cells, preventing ice crystal formation in their cells. They have acquired the capacity to repair damaged organs by placing their meristems underground in warmer temperatures.
Many flowers have dense hairs on leaves and stems that protect them from strong winds. They also have red-colored pigments that can convert sunlight into heat. Alpine plants reproduce sexually and asexually. The most common pollinators are bumblebees; however, they are scarce. To deal with this limitation, plants use flowering season and clonal propagation. Some plants may take up to two years to form flower sprouts, which survive the winter underground and usually produce seeds and fruits in the summer.
Animals in the alpine tundra have acquired especial adaptations that permit them to overcome climatic conditions present in the alpine tundra. Their bodies are coated with insulating layers of body fat which allow them to withstand the cold. Alpine animals also tend to have shorter ears, tails, and legs, reducing heat loss. Due to the widely dispersion of alpine tundra biomes in the world, there is no single animal species common to all regions of alpine tundra. The mountain goat is only found in North America. Llamas and chinchilla are native to the Andes in South America; however, many animal species are similar to those found in tundra or taiga biomes, including the hoary marmot, pika, chickaree and nutcracker.
The survival of a biome and its organisms depends on how well they´re adapted to a given ecosystem. Water runs-off down the mountains very rapidly. Soil is not able to hold sufficient water for plants to grow and the air is usually dry and windy. Some plants are able to store water in their thick leaves; others grow closer to the ground which keeps them hidden from the wind. Some species which used to found al lower latitudes are being forced to move to higher latitudes in search of more suitable habitats. Alpine biomes have been isolated subjected to the pressures of their ecosystem; however, human colonization, and global warming are among the most possible threats for alpine biomes. According to Global Environment, safety of wildlife species is based on providing them with legal protection, and preserving and managing their natural habitats.