Home >> Science & Nature >> Nature

Things About the Tundra Ecosystem

Tundras are a type of biome with low annual average temperatures and low amounts of precipitation, usually in the form of snow. Two types of tundra exist: the arctic tundra, which is around the North Pole, and the alpine tundra, which can be found on the tops of tall mountains. The tundra offers a harsh environment for the plants and animals that live on its frozen ground.

Plants
- The plants that grow in tundras tend to be short and shallowly rooted. Grasses, willows and sedges can be found there, although many of them are in dwarf forms. Mosses and lichens also grow in tundras, particularly in the colder regions. Summer is short on the tundra and temperatures are only above freezing for a few weeks, but the nearly round-the-clock daylight can result in explosive plant growth.
Animals
- Reindeer and caribou can be found in almost any tundra. Other animals that are important to the tundra include wolves, snow geese, tundra swans, musk oxen, ptarmigan, Dall sheep and brown bears. Near the coast, polar bears may live in the tundra. Small rodents and similar animals are also parts of the tundra ecosystem. Some insects that lay frost-resistant eggs can survive on the tundra and even thrive in the summer, but amphibians or reptiles can be found only rarely in the tundra.
Permafrost
- Permafrost -- a soil layer that stays frozen throughout the year -- heavily influences the biological make-up of the tundra. The top layer of the soil can thaw out briefly in the summer, but the soil beneath it remains frozen. Because it is frozen, it is biologically inactive; nothing can grow below the top layer of soil once it turns to permafrost. The permafrost also prevents animals from burrowing into the ground for warmth during the harsh winters, as they would do in other biomes; only animals that can withstand freezing temperatures can be found in the tundra.
Threats
- The tundra isn't threatened by urbanization like other biomes; few people are willing to build homes in such a harsh climate. Airborne pollutants such as PCBs and DDT can be found in measurable quantities on the tundra. The greatest threat to the tundra at present is from the oil and gas industry, which wants to develop some tundra areas, such the Arctic National Wildlife Refuge, for oil drilling. Global warming is also an up and coming problem; as the tundra's permafrost begins to melt, the dead plant material contained within it will begin to decay, releasing carbon dioxide and speeding global warming.

Nature