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Titel |
Forest decline caused by high soil water conditions in a permafrost region |
VerfasserIn |
H. Iwasaki, H. Saito, K. Kuwao, T. C. Maximov, S. Hasegawa |
Medientyp |
Artikel
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Sprache |
Englisch
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ISSN |
1027-5606
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Digitales Dokument |
URL |
Erschienen |
In: Hydrology and Earth System Sciences ; 14, no. 2 ; Nr. 14, no. 2 (2010-02-15), S.301-307 |
Datensatznummer |
250012184
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Publikation (Nr.) |
copernicus.org/hess-14-301-2010.pdf |
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Zusammenfassung |
In the permafrost region near Yakutsk, eastern Siberia, Russia, annual
precipitation (June–May) in 2005–2006 and 2006–2007 exceeded the 26-year
(1982–2008) mean of 222±68 mm by 185 mm and 128 mm, respectively,
whereas in 2007–2008 the excedent was only 48 mm, well within the range of
variability. Yellowing and browning of larch (Larix cajanderi Mayr.) trees occurred in an
undisturbed forest near Yakutsk in the 2007 summer growing season. Soil
water content at a depth of 0.20 m was measured along a roughly 400 m long
line transect running through areas of yellowing and browning larch trees
(YBL) and of normal larch trees (NL). In the two years of supranormal
precipitation, soil water content was very high compared to values
recorded for the same area in previous studies. For both wet years, the mean
degree of saturation (s) was significantly greater in YBL than NL areas,
whereas the converse was the case for the gas diffusivity in soil. This
implies that rather than mitigating water stress suffered during normal
precipitation years, elevated soil water conditions adversely affected the
growth of larch trees. Eastern Siberia's taiga forest extends widely into
the permafrost region. Was such supranormal annual precipitation to extend
for more than two years, as might be expected under impending global climate
changes, forest recovery may not be expected and emission of greenhouse gas
might continue in future. |
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