The Azimuth Project
Tundra

Contents

Idea

Tundra is a biome where the tree growth is hindered by low temperatures and short growing seasons. Beneath a layer of ‘active’ soil that thaws in summer, the soil in tundra regions is permafrost.

The ecotone (or ecological boundary region) between the tundra and the forest is known as the tree line or timberline. Tundra also abuts on regions of taiga.

Details

Climate

Acccording to the Wikipedia article on tundra:

Tundra climates ordinarily fit the Köppen climate classification ET, signifying a local climate in which at least one month has an average temperature high enough to melt snow (0°C or 32°F), but no month with an average temperature in excess of (10°C/50°F). The cold limit generally meets the EF climates of permanent ice and snows; the warm-summer limit generally corresponds with the poleward or altitudinal limit of trees, where they grade into the subarctic climates designated Dfd and Dwd (extreme winters as in parts of Siberia), Dfc typical in Alaska, Canada, European Russia, and Western Siberia (cold winters with months of freezing), or even Cfc (no month colder than -3°C as in parts of Iceland and southernmost South America). Tundra climates as a rule are hostile to woody vegetation even where the winters are comparatively mild by polar standards, as in Iceland.

Research

There was an EU-funded project on Tundra research:

TUNDRA stands for Tundra Degradation in the Russian Arctic. It is a research project funded for a period of 3 years (1998-2000) by the IVth Framework ‘Environment and Climate’ Programme of the European Commission. TUNDRA studies the effects of Global Change in the East-European Russian Arctic. The magnitude of expected climatic changes and the fragility of the environment make the Arctic a priority area to study the effects of global change.

The study area selected for the TUNDRA project is the Basin of the Usa River in the East-European Russian Arctic. The area is located at the latitude of the Arctic Circle. It has a total surface area of nearly 100.000 square kilometres. The Usa River flows from the Ural Mountains in the East to the Pechora River in the West, which in turn drains into the Pechora Bay and the Barents Sea.

Here is an interactive application showing subregions from that project.

References

Abstract: Emission of methane from tundra soil contributes about 10% of the global atmospheric methane budget. Moreover, tundra soils contain 15% of global soil carbon, so the response of this large carbon reservoir to projected global warming could be important. Coupled biological models predict that a warmer climate will increase methane emission through increased rates of methanogenesis. Microbial oxidation of methane is, however, a possible control on emissions that has previously been overlooked. Here we report the results of field and laboratory experiments on methane consumption by tundra soils. For methane concentrations ranging from below to well above ambient, moist soils were found to consume methane rapidly; in non-waterlogged soils, equilibration with atmospheric methane was fast relative to microbial oxidation. We conclude that lowering of the water table in tundra as a result of a warmer, drier climate will decrease methane fluxes and could cause these areas to provide a negative feedback for atmospheric methane.

category: ecology