Tundra | Definition, Climate, Animals, & Facts | Britannica
2024年12月12日 · tundra, a major zone of treeless level or rolling ground found in cold regions, mostly north of the Arctic Circle (Arctic tundra) or above the timberline on high mountains (alpine tundra). Tundra is known for large stretches of bare ground and rock and for patchy mantles of low vegetation such as mosses, lichens, herbs, and small shrubs.This surface supports a …
Tundra - Arctic, Flora, Fauna | Britannica - Encyclopedia Britannica
2024年12月12日 · Tundra organisms are opportunistic. Many species of plants are perennials that flower within a few days after the snow begins to melt, and some produce ripe seed within four to six weeks. Very few species are annuals. Plants 2.5 to 7.5 cm (1 to 3 inches) tall typically flower first, because they are in the warmer air layers near the soil surface.
Tundra - Arctic Animals, Plants, Ecosystems | Britannica
2024年12月12日 · Tundra - Arctic Animals, Plants, Ecosystems: Organisms of the northern alpine tundra probably evolved before those of the Arctic tundra, appearing first in the Mongolo-Tibetan Plateau. Few alpine animals, however, contributed directly to the evolution of Arctic tundra species, because physical barriers prevented the migration of species and because alpine and …
tundra summary | Britannica
In the Arctic tundra they include lemmings, the Arctic fox, the Arctic wolf, caribou, reindeer, and musk-oxen. In the alpine tundra many animals, including mountain sheep and wildcats, descend to warmer zones during winter. The climate of alpine tundra is more moderate and has a higher amount of rainfall than does Arctic tundra.
tundra - Kids | Britannica Kids | Homework Help
Tundra animals must be able to survive long, cold winters. Many birds live there in the summer, but few stay through the winter. Some common tundra animals are reindeer, Arctic foxes, snowy owls, musk oxen, and polar bears. Very few people live in the tundra.
tundra Facts | Britannica
Tundra, a cold region of treeless level or rolling ground found mostly north of the Arctic Circle or above the timberline on mountains. Tundra is known for large stretches of bare ground and rock and for patchy mantles of low vegetation such as mosses, lichens, herbs, and small shrubs.
Arctic tundra | Britannica
Other articles where Arctic tundra is discussed: Arctic: Traditional culture: …ecosystems, the taiga and the tundra. The open terrain of the tundra permits the supervision of large herds, and these generally migrate with their herdsmen between winter pastures within the margins of the taiga and summer pastures out on the tundra. Such pastoralism therefore entails fairly extended …
tundra - Students | Britannica Kids | Homework Help
This freeze-thaw cycle sets the tundra apart from two ecosystems frequently found adjacent to it—the icy polar barrens and the evergreen boreal forest. Permafrost—perennially frozen ground—is a significant feature of the Arctic tundra; however, it does not typically occur in alpine regions. Plants and Animals
Tundra - Arctic, Low Vegetation, Permafrost | Britannica
2024年12月12日 · Tundra - Arctic, Low Vegetation, Permafrost: An important measure of natural ecosystems is the biological production of its plants and animals—that is, the total amount of biomass produced by living organisms within a given area in a specific period of time. In polar regions the greatest biological production occurs in marine waters rather than on land, and …
Tundra - Climate Change, Human Impact, Arctic | Britannica
2024年12月12日 · Tundra - Climate Change, Human Impact, Arctic: Earth’s tundra regions are harsh and remote, so fewer humans have settled there than in other environments. However, humans have a long history in the tundra. For example, the first people who went to North America from Asia more than 20,000 years ago traveled through vast tundra settings on both …