Magellanic moorland

The Magellanic moorland or Magellanic tundra (Spanish: Tundra Magallánica) is an ecoregion on the Patagonian archipelagos south of latitude 48° S. It is characterized by high rainfall with a vegetation of scrubs, bogs and patches of forest in more protected areas. Cushion plants, grass-like plants and bryophytes are common.[1]

Magellanic moorland at Herschel Island, Cabo de Hornos National Park.

At present there are outliers of Magellanic moorland as far north as in the highlands of Cordillera del Piuchén (latitude 42° 22' S) in Chiloé Island.[2][3] During the Llanquihue glaciation Magellanic moorland extended to the non-glaciated lowlands of Chiloé Island[2] and further north to the lowlands of Chilean lake district (latitude 41° S).[4]

The classification of Magellanic moorland has proven problematic as substrate, low temperatures and exposure to the ocean influences the development of the Magallanic moorland. It thus may qualify either as polar tundra or heathland.[5]

Flora and plant communities

Edmundo Pisano identifies the following plant communities for the Magellanic moorland:

  1. Bogs[6]
    1. Sphagnum bogs[6]
      1. Magellanic sphagnum tundra[6]
      2. Juncus bogs[7]
    2. Non-sphagniferous bryophytic tundra[8]
      1. Non-sphagnum moss bog[9]
      2. Hepatica bogs[9]
  2. Pluvinar mires[10]
    1. Hygrophytic mire tundra[10]
    2. Montane pulvinar tundra[11]
    3. Bryophyte and dwarf shrub tundra[12]
  3. Gramineous mires[13]
    1. Tufty sedge tundra[14]
    2. Subantarctic gramineous mire[14]
  4. Woody synusia tundras[15]
    1. Tundras with Pilgerodendron uvifera[16]
      1. Association Pilgerodendretum uviferae[16]
        1. Sub-association Pilgerodendro-Nothofagetum betuloidis[17]
        2. Sub-association Nano-Pilgerodendretum uviferae[18]
    2. Interior nanophanerophytic tundras[19]
      1. Interior heath of low to medium elevation[19]
      2. Montane nanophaneritic tundra[20]

Where forests occur they are made up of the following trees Nothofagus betuloides (coigüe de Magallanes), Drimys winteri (canelo), Pseudopanax laetevirens (sauco del diablo), Embothrium coccineum (notro), Maytenus magellanica (maitén), Pilgerodendron uviferum (ciprés de las Guaitecas) and Tepualia stipularis (tepú).[21]

Soils and climate

Soils are usually rich in turf and organic matter and poor in bases. Often they are also water-saturated.[22] Granitoids, schists and ancient volcanic rocks make up the basement on which soils develop.[23] Any previously existing regolith has been eroded by the Quaternary glaciations.[23] It is not rare for bare rock surfaces to be exposed in the interior of islands.[24]

The climate where Magellanic moorland grows can be defined as oceanic, snowy and isothermal[24][25] with cool and windy summers.[26] In the Köppen climate classification it has a tundra climate ET.[24][25]

References
  1. "Magellanic subpolar forests". Terrestrial Ecoregions. World Wildlife Fund.
  2. Villagrán, Carolina (1988). "Expansion of Magellanic Moorland during the Late Pleistocene: Palynological Evidence from Northern isla de Chiloé, Chile". Quaternary Research. 30 (3): 304–314. doi:10.1016/0033-5894(88)90006-3.
  3. Ramírez, Carlos; San Martin, Cristina; Vidal, Osvaldo; Pérez, Yéssica; Valenzuela, Jorge; Solís, José-Luís; Toledo, Gisela (2014). "Tundra Subantártica en la Isla Grande de Chiloé, Chile: Flora y vegetación turbosa de campañas" [Subantarctic Tundra in Chiloé Island, Chile: Flora and vegetation of "Campañas" peat bogs]. Anales del Instituto de la Patagonia (in Spanish). 42 (2): 17–37. doi:10.4067/S0718-686X2014000200002.
  4. Moreno, Patricio I.; Denton, Geoge H.; Moreno, Hugo; Lowell, Thomas V.; Putnam, Aaron E.; Kaplan, Michael R. (2015). "Radiocarbon chronology of the last glacial maximum and its termination in northwestern Patagonia". Quaternary Science Reviews. 122: 233–249. doi:10.1016/j.quascirev.2015.05.027. hdl:10533/148448.
  5. Longton, R.E. (1988). Biology of Polar Bryophytes and Lichen. Studies in Polar Research. Cambridge University Press. p. 20. ISBN 0-521-25015-3.
  6. Pisano (1977), p. 219
  7. Pisano (1977), p. 223
  8. Pisano (1977), p. 225
  9. Pisano (1977), p. 226
  10. Pisano (1977), p. 229
  11. Pisano (1977), p. 230
  12. Pisano (1977), p. 231
  13. Pisano (1977), p. 232
  14. Pisano (1977), p. 233
  15. Pisano (1977), p. 236
  16. Pisano (1977), p. 237
  17. Pisano (1977), p. 239
  18. Pisano (1977), p. 240
  19. Pisano (1977), p. 242
  20. Pisano (1977), p. 244
  21. Heusser, C.J. (2004). Ice Age Southern Andes. Developments in Quaternary Science. Elsevier. pp. 56–59.
  22. Pisano (1977), p. 128
  23. Pisano (1977), p. 129
  24. Pisano (1977), p. 145
  25. Pisano (1977), p. 144
  26. Arroyo, M.T.K.; Pliscoff, P.; Mihoc, R.; Arroyo-Kalin, M. (2005). "The Magellanic moorland". In Fraser, Lauchlan H.; Keddy, Paul A. (eds.). The World's Largest Wetlands: Ecology and Conservation. Cambridge University Press. p. 424–445. ISBN 978-0-52183404-9.
Bibliography
  • Pisano Valdés, E. (1977). "Fitogeografía de Fuego-Patagonia chilena. I.-Comunidades vegetales entre las latitudes 52 y 56º S". Anales del Instituto de la Patagonia (in Spanish). VIII. Punta Arenas.
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