Steppa dei mammut

La cosiddetta Steppa dei mammut era il bioma più comune sul pianeta Terra durante l'Ultimo massimo glaciale (c.a. 20.000 anni fa), esteso dalla Spagna al Canada, attraverso tutta l'Eurasia, e dall'Artico alla Cina meridionale^[2]^[3]^[4]^[5]^[6]. Era caratterizzata da un clima freddo e secco^[7]^[6]. La flora era dominata dall'erba e dagli arbusti (Artemisia, Cyperaceae, ecc.)^[3]^[6]^[8], con macchie di betulle nane e larici, e la fauna da bisonti, cavalli e mammut (v. c.d. Megafauna del Pleistocene)^[7] dai quali il bioma prende il nome^[9]^[10]. Quest'ecosistema, occupante ampie aree del settentrione del globo, perdurò per circa 100.000 anni salvo poi scomparire 12.000 anni fa^[7].

Durante l'Olocene, le specie adattatesi all'ambiente arido si estinsero o ridussero notevolmente il loro habitat^[7]. Il clima freddo-secco dell'ultimo massimo glaciale persiste oggi nell'estremo oriente della regione compresa tra i Monti Sajany ed i Monti Altaj (Eurasia centrale).^[1]^[11]^[12] Paleo-biomi recentemente ricostruiti, ^[1]^[13] unitamente allo studio dei pollini,^[14]^[15]^[16]^[17] hanno suggerito che le aree dell'Altai-Sajany possono essere considerate come un'effettiva vestigia delle steppe dei mammut^[1] il cui ambiente permane immutato da 40 000 anni, costituendosi quale "Riserva dell'Ultimo massimo glaciale". La regione, nel Pleistocene come oggi, supporta la sopravvivenza di grandi erbivori e carnivori in un contesto di steppa, deserto e montagna non intervallati da foreste. Nessuna delle specie di mammiferi del Pleistocene sopravvive nelle foreste temperate, nella taiga o nella tundra. L'Altopiano di Ukok, nel sud dell'Altaj, e il lago Har-Us nuur nella Mongolia occidentale hanno preservato dall'Era glaciale sia la renna sia la saiga tatarica.^[1]

[1]
Věra Pavelková Řičánková, Jan Robovský e Jan Riegert, Ecological Structure of Recent and Last Glacial Mammalian Faunas in Northern Eurasia: The Case of Altai-Sayan Refugium, in PLoS ONE, vol. 9, n. 1, 2014, pp. e85056, Bibcode:2014PLoSO...985056P, DOI:10.1371/journal.pone.0085056, PMC 3890305, PMID 24454791.
[2]
J. M. Adams, H. Faure, L. Faure-Denard, J. M. McGlade e F. I. Woodward, Increases in terrestrial carbon storage from the Last Glacial Maximum to the Present, in Nature, vol. 348, n. 6303, 1990, pp. 711–714, Bibcode:1990Natur.348..711A, DOI:10.1038/348711a0.
[3]
Guthrie, R.D., Frozen Fauna of the Mammoth Steppe, The University of Chicago Press, Chicago, 1990, ISBN 978-0-226-15971-3.
[4]
Sher, A.V., 1997. Nature restructuring in the East-Siberian Arctic at the Pleistocene Holocene boundary and its role in mammal extinction and emerging of modern ecosystems. Earth Cryosphere 1 (3e11), 21e29.
[5]
Diego J. Álvarez-Lao e Nuria García, Geographical distribution of Pleistocene cold-adapted large mammal faunas in the Iberian Peninsula, in Quaternary International, vol. 233, n. 2, 2011, pp. 159–170, Bibcode:2011QuInt.233..159A, DOI:10.1016/j.quaint.2010.04.017.
[6]
S.A. Zimov, N.S. Zimov, A.N. Tikhonov e F.S. Chapin, Mammoth steppe: A high-productivity phenomenon, in Quaternary Science Reviews, vol. 57, 2012, pp. 26–45, Bibcode:2012QSRv...57...26Z, DOI:10.1016/j.quascirev.2012.10.005.
[7]
Guthrie, R.D., Origin and causes of the mammoth steppe: a story of cloud cover, woolly mammal tooth pits, buckles, and inside-out Beringia, Quaternary Science Reviews, 20 (2001) p. 549-574.
[8]
A.V. Sher, S.A. Kuzmina, T.V. Kuznetsova e L.D. Sulerzhitsky, New insights into the Weichselian environment and climate of the East Siberian Arctic, derived from fossil insects, plants, and mammals, in Quaternary Science Reviews, vol. 24, 5–6, 2005, pp. 533–569, Bibcode:2005QSRv...24..533S, DOI:10.1016/j.quascirev.2004.09.007.
[9]
Guthrie, R. Dale: Mammals of the mammoth steppe as paleoenvironmental indicators. In: Hopkins, D.M., Schweger, C.E., Young, S.B. (ed.): Paleoecology of Beringia. Academic Press, New York 1982, pp. 307–329.
[10]
Blinnikov, Mikhail S., Gaglioti, Benjamin, Walker, Donald A., Wooller, Matthew J., Zazula, Grant D.: Pleistocene graminoid-dominated ecosystems in the Arctic. In: Quaternary Science Reviews, 30 (October 2011) pp. 2906–2929, DOI: 10.1016/j.quascirev.2011.07.002
[11]
Frenzel B, Pécsi M, Velichko AA. (1992). Atlas of paleoclimates and paleoenvironments of the Northern Hemisphere. JenaNew York: Geographical Research Institute, Hungarian Academy of Sciences Budapest and Gustav Fischer Verlag Stuttgart. 153 p
[12]
Agadjanian AK, Serdyuk NV. (2005). The history of mammalian communities and paleogeography of the Altai Mountains in the Paleolithic. Paleontological Journal, 39: 645–821.
[13]
P. E. Tarasov, V. S. Volkova, T. Webb, J. Guiot, A. A. Andreev, L. G. Bezusko, T. V. Bezusko, G. V. Bykova, N. I. Dorofeyuk, E. V. Kvavadze, I. M. Osipova, N. K. Panova e D. V. Sevastyanov, Last glacial maximum biomes reconstructed from pollen and plant macrofossil data from northern Eurasia, in Journal of Biogeography, vol. 27, n. 3, --, pp. 609–620, DOI:10.1046/j.1365-2699.2000.00429.x, ISSN 0305-0270,1365-2699 (WC · ACNP).
[14]
Tarasov PE, Guiot J, Cheddadi R, Andreev AA, Bezusko LG, et al. (1999). Climate in northern Eurasia 6000 years ago reconstructed from pollen data. Earth Planet Sci Lett 171: 635–645. doi: 10.1016/s0012-821x(99)00171-5
[15]
Jankovská V, Pokorný P. (2008). Forest vegetation of the last full-glacial period in the Western Carpathians (Slovakia and Czech Republic). Preslia 80: 307–324.
[16]
Kuneš P, Pelánková B, Chytrý M, Jankovská V, Pokorný P, et al. (2008). Interpretation of the last-glacial vegetation of eastern-central Europe using modern analogues from southern Siberia. J Biogeogr, 35: 2223–2236. doi: 10.1111/j.1365-2699.2008.01974.x
[17]
Pelánková B, Chytrý M (2009). Surface pollen-vegetation relationships in the forest-steppe, taiga and tundra landscapes of the Russian Altai Mountains. Rev Palaeobot Palyno 157: 253–265. doi: 10.1016/j.revpalbo.2009.05.005

Portale Ecologia e ambiente

Portale Storia

[pavelkova2014-1] [1]
Věra Pavelková Řičánková, Jan Robovský e Jan Riegert, Ecological Structure of Recent and Last Glacial Mammalian Faunas in Northern Eurasia: The Case of Altai-Sayan Refugium, in PLoS ONE, vol. 9, n. 1, 2014, pp. e85056, Bibcode:2014PLoSO...985056P, DOI:10.1371/journal.pone.0085056, PMC 3890305, PMID 24454791.

[adams1990-2] [2]
J. M. Adams, H. Faure, L. Faure-Denard, J. M. McGlade e F. I. Woodward, Increases in terrestrial carbon storage from the Last Glacial Maximum to the Present, in Nature, vol. 348, n. 6303, 1990, pp. 711–714, Bibcode:1990Natur.348..711A, DOI:10.1038/348711a0.

[guthrie1990-3] [3]
Guthrie, R.D., Frozen Fauna of the Mammoth Steppe, The University of Chicago Press, Chicago, 1990, ISBN 978-0-226-15971-3.

[sher1997-4] [4]
Sher, A.V., 1997. Nature restructuring in the East-Siberian Arctic at the Pleistocene Holocene boundary and its role in mammal extinction and emerging of modern ecosystems. Earth Cryosphere 1 (3e11), 21e29.

[alvarez2011-5] [5]
Diego J. Álvarez-Lao e Nuria García, Geographical distribution of Pleistocene cold-adapted large mammal faunas in the Iberian Peninsula, in Quaternary International, vol. 233, n. 2, 2011, pp. 159–170, Bibcode:2011QuInt.233..159A, DOI:10.1016/j.quaint.2010.04.017.

[zimov2012-6] [6]
S.A. Zimov, N.S. Zimov, A.N. Tikhonov e F.S. Chapin, Mammoth steppe: A high-productivity phenomenon, in Quaternary Science Reviews, vol. 57, 2012, pp. 26–45, Bibcode:2012QSRv...57...26Z, DOI:10.1016/j.quascirev.2012.10.005.

[guthrie2001-7] [7]
Guthrie, R.D., Origin and causes of the mammoth steppe: a story of cloud cover, woolly mammal tooth pits, buckles, and inside-out Beringia, Quaternary Science Reviews, 20 (2001) p. 549-574.

[sher2005-8] [8]
A.V. Sher, S.A. Kuzmina, T.V. Kuznetsova e L.D. Sulerzhitsky, New insights into the Weichselian environment and climate of the East Siberian Arctic, derived from fossil insects, plants, and mammals, in Quaternary Science Reviews, vol. 24, 5–6, 2005, pp. 533–569, Bibcode:2005QSRv...24..533S, DOI:10.1016/j.quascirev.2004.09.007.

[guthrie1982-9] [9]
Guthrie, R. Dale: Mammals of the mammoth steppe as paleoenvironmental indicators. In: Hopkins, D.M., Schweger, C.E., Young, S.B. (ed.): Paleoecology of Beringia. Academic Press, New York 1982, pp. 307–329.

[blinnikov2011-10] [10]
Blinnikov, Mikhail S., Gaglioti, Benjamin, Walker, Donald A., Wooller, Matthew J., Zazula, Grant D.: Pleistocene graminoid-dominated ecosystems in the Arctic. In: Quaternary Science Reviews, 30 (October 2011) pp. 2906–2929, DOI: 10.1016/j.quascirev.2011.07.002

[frenzel1992-11] [11]
Frenzel B, Pécsi M, Velichko AA. (1992). Atlas of paleoclimates and paleoenvironments of the Northern Hemisphere. JenaNew York: Geographical Research Institute, Hungarian Academy of Sciences Budapest and Gustav Fischer Verlag Stuttgart. 153 p

[agadjanian2005-12] [12]
Agadjanian AK, Serdyuk NV. (2005). The history of mammalian communities and paleogeography of the Altai Mountains in the Paleolithic. Paleontological Journal, 39: 645–821.

[tarasov2000-13] [13]
P. E. Tarasov, V. S. Volkova, T. Webb, J. Guiot, A. A. Andreev, L. G. Bezusko, T. V. Bezusko, G. V. Bykova, N. I. Dorofeyuk, E. V. Kvavadze, I. M. Osipova, N. K. Panova e D. V. Sevastyanov, Last glacial maximum biomes reconstructed from pollen and plant macrofossil data from northern Eurasia, in Journal of Biogeography, vol. 27, n. 3, --, pp. 609–620, DOI:10.1046/j.1365-2699.2000.00429.x, ISSN 0305-0270,1365-2699 (WC · ACNP).

[tarasov1999-14] [14]
Tarasov PE, Guiot J, Cheddadi R, Andreev AA, Bezusko LG, et al. (1999). Climate in northern Eurasia 6000 years ago reconstructed from pollen data. Earth Planet Sci Lett 171: 635–645. doi: 10.1016/s0012-821x(99)00171-5

[jankovska2008-15] [15]
Jankovská V, Pokorný P. (2008). Forest vegetation of the last full-glacial period in the Western Carpathians (Slovakia and Czech Republic). Preslia 80: 307–324.

[kunes2008-16] [16]
Kuneš P, Pelánková B, Chytrý M, Jankovská V, Pokorný P, et al. (2008). Interpretation of the last-glacial vegetation of eastern-central Europe using modern analogues from southern Siberia. J Biogeogr, 35: 2223–2236. doi: 10.1111/j.1365-2699.2008.01974.x

[pelankova2009-17] [17]
Pelánková B, Chytrý M (2009). Surface pollen-vegetation relationships in the forest-steppe, taiga and tundra landscapes of the Russian Altai Mountains. Rev Palaeobot Palyno 157: 253–265. doi: 10.1016/j.revpalbo.2009.05.005

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[17]

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Steppa dei mammut

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