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What Are Liverworts of the Tundra?

The tundra is one of the Earth's biomes -- large geographical areas characterized by their climates, plants and animals.This enormous biome, which covers one-fifth of the Earth's surface, is composed of a permanently frozen layer of soil called permafrost. During short warmer periods of summer, the top soil thaws enough to accommodate a few plants. One such plant is the liverwort.

Liverworts
- Liverworts, the simplest true plants, are nonvascular plants whose ribbon-like leaves have the shape of lobes of the human liver. The name, an Anglo-Saxon word, means "liver plant" and early Brits thought the genus Marchantia cured liver ailments. Liverworts used to be classified along with mosses and hornworts into one plyllum Bryophyta, but now they have their own phylum Hepatophyta. The approximately 8,500 species of liverworts reproduce by spores.
Liverworts in the Arctic Tundra
- The arctic tundra is found mostly in the northern hemisphere north of the taiga belt. Svalbard, an archipelago in the northern part of Norway, had 85 species of liverworts in 1995, and Iceland had 146 liverwort species in 1983. Of Arctic Alaska tundra's 135 species (as of 1988), two liverworts still existing on Alaska's arctic tundra are members of the family ptilidiaceae . The Marchantia polymorpha L., a large flat liverwort, is unisexual with the male plants having lobed discs while the female parts are finger-like lobes cropping out of the main stalk. Ptilidium ciliare, an example of a leafy liverwort, is common in moist tundra. Its concave leaves have ciliated margins and look inflated.
Liverworts in Antarctic Tundra.
- In Antarctica, where 1 percent of the land is free of snow and available to plants, 150 species of liverworts were found in 1988. At Mount Flora at Hope Bay, in Antarctic Peninsula, West Antarctica, liverworts called Schizolepidella gracilis and the Schizalepidella birkenmajert exist. The Schizolepidella genus represents the world's oldest liverworts of the Jungermanialess order. Out of the flora on Mount Flora during the Early Jurassic time which included conifers, horsetails, ferns, cycads, seed ferns and bennettitales, these liverworts are the only plants still present. Antarctic tundra in the Antarctic Peninsula has 25-30 species of liverworts.
Liverworts in the Alpine Tundra
- Alpine tundra comprises cold, windswept, treeless areas located on mountaintops and other high elevations. Examples are the paramos, the humid, high, cold habitats of the Andes Mountains in Northern South America which make up to about 2 percent of the total land area of the countries in which they are found. Of the 265 types of liverworts found in these areas, about 25 percent are endemic.

Nature