1 resultado para Sub Antartic Front( SAF)

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo (BDPI/USP)


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The sub-Antarctic Magellanic ecoregion harbors a high diversity of bryophytes, greater than the species richness of vascular plants. Despite this fact, phenological studies on bryophytes are lacking for this ecoregion and Chile. Based on the study of the sporophytic phase of Tayloria dubyi, an endemic moss from the sub-Antarctic Magellanic ecoregion, we propose a methodology for phonological studies on austral bryophytes. We defined five phenophases, easily distinguishable with a hand-lens, which were monthly recorded during 2007 and 2008 in populations of T dubyi at the Omora Ethnobotanical Park and Mejillones Bay on Navarino Island (55 degrees S) in the Cape Horn Biosphere Reserve. The sporophytic (or reproductive) phase of T. dubyi presented a clear seasonality. After growing in November, in three months (December-February) of the austral reproductive season the sporophytes mature and release their spores; by March they are already senescent. T. dubyi belongs to the Splachnaceae family for which entomochory (dispersal of spores by insects, specifically Diptera) has been detected in the Northern Hemisphere. The period of spores release in T. dubyi coincides with the months of highest activity of Diptera which are potential dispersers of spores; hence, entomochory could also take place in sub-Antarctic Magellanic ecoregion. In sum, our work: (i) defines a methodology for phenological studies in austral bryophytes, (ii) it records a marked seasonality ion the sporophyte phase of T dubyi, and (iii) it proposes to evaluate in future research the occurrence of entomochory in Splachnaceae species growing in the sub-Antarctic peatlands and forest ecosystems in the Southern Hemisphere.