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Titel |
Fire cue effects on seed germination of six species of northwestern Patagonian grasslands |
VerfasserIn |
S. L. Gonzalez, L. Ghermandi |
Medientyp |
Artikel
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Sprache |
Englisch
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ISSN |
1561-8633
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Digitales Dokument |
URL |
Erschienen |
In: Natural Hazards and Earth System Science ; 12, no. 9 ; Nr. 12, no. 9 (2012-09-06), S.2753-2758 |
Datensatznummer |
250011090
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Publikation (Nr.) |
copernicus.org/nhess-12-2753-2012.pdf |
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Zusammenfassung |
Postfire recruitment of seedlings has been attributed to a stimulation of
germination by fire-related cues. The germination response to heat shock
(80 °C – 5 min), smoke (60 min), the combination of both factors
and no heat no smoke (control) was studied in six native species (two
dominant grasses, two dominant shrubs and two annual fugitive herbs) of
northwestern Patagonian grasslands. Seeds of the grasses Festuca
pallescens and Stipa speciosa and the shrub Senecio
bracteolatus (Asteraceae) germinated when they were exposed to heat shock,
whereas seeds of the other shrub, Mulinum spinosum (Apiaceae), were
killed by this fire cue. In grasses, probably the glume of caryopsis
protected embryos from heat. Possibly, the seed size could explain the
different responses of the two shrubs. Heat combined with smoke reduced seed
germination for S. speciosa and S. bracteolatus. The heat could
have scarified seeds and the longer exposure to smoke could have been toxic
for embryos. The same treatment increased germination of the annual fugitive
herb Boopis gracilis (Calyceraceae). We
concluded that fire differentially affects the seedling recruitment of the
studied species in the northwestern Patagonian grasslands. |
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