The Alpine Tundra is a unique biome in that it’s found all over the globe, but only on tops of the tallest mountains. While temperature and rainfall usually determine the other biomes, this one is defined mostly by elevation. This elevation causes extreme conditions, which create a unique tundra environment where only the hardiest plants and animals can survive.
He mapped the life-zones with elevation. Today, we still use these life-zone classifications.
In the late 1800’s a man by the name of C. Hart Merriam was surveying the land from the bottom of the Grand Canyon to the top of the mountain peaks. He noticed that distinct plant communities were found as one increased elevation. He noticed that lower elevations were prairies, then dry steppes, Ponderosa Pine, montane forests, subalpine forests and finally the alpine tundra.
These life-zones will change with elevation and are somewhat tied to latitude. The alpine tundra represents the highest of the zones. Every thousand feet of elevation you climb represents about 600 miles north in latitude. That means you reach the alpine tundra at lower elevations, the farther north you travel.
Alpine Tundra, the highest life-zone
The tallest life-zone, the alpine tundra can be found at any latitude on earth. yet, the elevation that the alpine tundra begins is different depending on where you are.
For instance, on the tall Mexican Volcanos, the tree-line is much higher than anywhere in the United states. It occurs around 13,000 feet.
In Colorado, the Tundra begins around 11,500 feet. Farther north, in Alaska, the Tundra can form at only a few thousand feet elevation!
Micro-habitats in the Alpine Tundra
The alpine tundra is not a homogenous zone where plants have equal opportunity to grow. Small changes in elevation in this zone and patches of snow and rock create microhabitats where different species of plant and animal can specialize. For instance, a small depression on the ground might decrease sun and wind intensity causing snow to accumulate. Snowbanks are hard places for plants to grow because areas where snow builds up decreases the already short growing season. Thus, small elevation changes that increase light intensity may be just enough for small plants to make a living.
Some of the major micro-habitats found in the Alpine tundra are Meadows, snow beds, talus fields, and fell-fields. You can imagine that plants growing in one habitat are going will need different adaptations to grow in others.
Very few animals are found in this habitat year round. Some of the few that do make their home here year-round are yellow-bellied marmots, pikas, and ptarmagins. Each has unique adaptations to allow them to live here.
Yellow bellied marmots that live in Colorado will hibernate for as many as 8 months out of the year.
Yellow bellied marmots (hibernate for 8 months of the year). Pikas don’t hibernate. They hide from the weather under rocks in the boulder fields. They store food in haypiles and munch them until real food is available. Pikas are related to rabbits and hares, not rodents.
Tundra is derived from the Lappish language and means “land of no trees”.
Notable animals in the alpine tundra include, Kea parrots, marmots, Mountain goats, and pika.
Alpine tundra does not map directly to specific WWF ecoregions. Portions of Montane grasslands and shrublands ecoregions include alpine tundra. The alpine tundra also has elks,marmots, mountain goats, pikas, and sheep