Fellfields

"Fell-field" has been used to describe physical and landscape forms as well as specific plant communities. As a landscape form, fell-fields refer to tracts of bare, high mountainous ground with sparse vegetation. The Danish botanist Eugenius Warming first used the expression in his classic exploration of the relationships between plants and their environment (Oecology of Plants. An Introduction to the Study of Plant Communities, 1909), classifying extensive areas of northeast Greenland as fjeld-mark, translated into English as "fell-field." Warming defined fell-fields firstly in terms of the dwarf nature of their plants, and secondly by the extent of bare substrate (for example, soil, gravel, or rock). He considered that the cushion form or short stature of the plants was a result of the brief cold summer (the mean temperature of the warmest month being less than 6°C), since there were sufficient nutrients and water in the soil to potentially sustain greater growth. He made the link between such communities in alpine Europe and in the Arctic, based on the similar prevailing environmental conditions that shaped their existence. In his descriptions, Warming did not define the extent to which fell-field vegetation covered the substrate, but it is now generally recognized that in such communities, higher-plant ground cover rarely exceeds 60% and may comprise less than 5%. However, in many Arctic areas, the "bare" substrate is covered by an organic crust (cryptogram) that can be composed of blue-green algae, extensive lichen growth, and desiccated bryophytes that, while appearing bare, is certainly not devoid of plant life.

In looking at vegetation with fresh eyes, Warming was describing fell-field vegetation in terms of form and structure, rather than an assemblage of taxonomi-cally defined species, and it is for this reason that it remains hard to define the vegetation type to the present. The low, creeping growth forms of typical species certainly result from wind exposure and/or low temperatures, the combined effect of which is often a lack of snow cover to protect from penetrating frosts in winter and lack of accumulation of loess or organic material to retain nutrients and moisture in summer. In some situations, the extremely dry nature of the habitat in summer will therefore also shape plant growth forms. The general lack of continuous higher plant vegetation cover may result from an array of processes, such as lack of soil to retain moisture, solifluction processes, patterned ground, or simple instability of the substrate. Typical species varies according to these processes; for example, patterned ground may have Saxifraga species and other herbs on the unstable, wet clayey centers, but dwarf shrubs may characterize the dry gravely polygon ridges. Nevertheless, in the original Greenland habitats, the dry barren types of fell-field may be characterized by the nature of the dominant species present. These may be either heath- (comprising species such as Alpine azalea Loiseleuria procumbens), herb- (e.g., mountain avens Dryas species, or Diapensia Diapensia lapponica), or graminoid-dominated (e.g., nard sedge Carex nardina, three-leaved rush Juncus trifidus). Very similar habitat types exist throughout the globe in alpine situations well south of the Arctic region. These include the highlands of Scotland (where Juncus trifidus and other Arctic species may occur), the Sierra Nevada of California, and the mountains of New Zealand (where different genera occur such as the remarkable vegetable sheep Raoulia bryoides and Haastia pulvinaris showing the extreme forms of cushion habit of Northern Hemisphere plants).

Tony Fox

See also Dry Tundra Further Reading

Bocher, T.W., "Studies of the vegetation of the east coast of Greenland between Scoresby Sound and Angmagssalik (Christian IX Land)." Meddelelser om Gr0nland, 104(4) (1933): 1-134

-, "Oceanic and continental vegetational complexes in

Southwest Greenland." Meddelelser om Gr0nland, 148(l) (1954): 1-336

Holland, R.F., Preliminary Descriptions of the Terrestrial Natural Communities of California, Sacramento, California: Department of Fish and Game, 1986

Warming, E., Oecology of Plants, Oxford: Oxford University Press, 1909

-, "The vegetation of Greenland." Greenland, 1 (1928):

291-317

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