The ecology of sublithic terrestrial algae at the Vestfold Hills, Antarctica

Broady, Paul A.

doi:10.1080/00071618100650241

Cited by 71 publications

(60 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Recently, hypolithic communities in the southern low altitude Dry Valley regions have been shown to be capable of acetylene reduction, the accepted functional proxy for dinitrogen fixation. The observation that cyanobacterial Chroococcidiopsis-like phylotypes in endoliths and casmoliths and Leptolyngbia in endoliths are dominant members of the respective communities is entirely consistent with previous microscopic (7,14) and phylogenetic observations (15).…”

supporting

confidence: 77%

Cryptic microbial communities in Antarctic deserts

Cowan

2009

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

supporting

confidence: 77%

Cryptic microbial communities in Antarctic deserts

Cowan

2009

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

“…(Warren-Rhodes et al 2007), whilst in others, a more diverse range of taxa have been identified (Tracy et al 2010). Polar hypolithons comprise a relatively diverse cyanobacterial assemblage comprising various Oscillatoriales, Aphanocapsa, Aphanothece, Chroococcidiopsis and Gloeocapsa morphotypes (Broady 1981(Broady , 2005Cockell and Stokes 2004). Culture-independent molecular studies have revealed a greater cyanobacterial diversity (Wood et al 2008) than identified by microscopy and have indicated the presence of diverse bacterial phylotypes (Pointing et al 2009;Khan 2009).…”

Section: Introductionmentioning

confidence: 99%

Distribution and abiotic influences on hypolithic microbial communities in an Antarctic Dry Valley

et al. 2010

View full text Add to dashboard Cite

The Miers Valley within the McMurdo DryValleys of Antarctica supports abundant quartz and marble substrates for hypolithons-microbial colonists on the underside of these translucent rocks. Three physically distinct hypolithic community types have been identified: cyanobacteria dominated (Type I), fungus dominated (Type II) or moss dominated (Type III). The distribution of the three types was mapped across much of the *75 km 2 area of the upper Miers Valley and correlated this with the measurements of selected micro-environmental variables. Type I hypolithons were most common and occurred at all altitudes up to 824 m, whilst Type II and Type III hypolithons were less abundant and restricted to lower altitudes on the valley floor (\415 m and \257 m, respectively). Whilst all colonized quartz effectively filtered incident UVB irradiance, transmittance levels for UVA and PAR varied markedly and were significant in determining hypolith type. Notably, the Type I hypolithons occurred under rocks with a significantly lower transmittance of photosynthetically active radiation than Type II and III hypolithons. Altitude and aspect were also significant factors determining hypolith type, and a role for altitude-related abiotic variables in determining the distribution of Type I, II and III hypolithons is proposed.

show abstract

“…In polar (cold) desert areas, hypolithic communities are also commonly found where suitable lithic substrates occur (Broady 1981;Cockell and Stokes 2004;Cowan et al , 2011aCowan et al , 2011bKhan et al 2011;Chan et al 2012). The hypolithic communities of the Miers Valley (McMurdo Dry Valleys, South Victoria Land, eastern Antarctica), which supports abundant hypolithic colonization under quartz and marble substrates (Cowan et al 2011a), are the most extensively studied.…”

Section: Introductionmentioning

confidence: 99%

The spatial structures of hypolithic communities in the Dry Valleys of East Antarctica

2014

View full text Add to dashboard Cite

Hypolithic communities represent important reservoirs of microbial life in hyper-arid deserts. A number of studies on the diversity and ecology of these communities from different geographic areas have been reported in the past decade, but the spatial distribution of the different components of these communities is still not understood. Moss-and cyanobacteria-dominated hypolithic communities morphotypes from Miers Valley (McMurdo Dry Valleys, East Antarctica) were analyzed by electron microscopy in order to characterize the micro-scale spatial structure. The two communities showed a high degree of internal organization, but differing according to the biological composition. In moss-dominated hypoliths, the moss plantlets are intermixed with mineral fragments of soil origin. However, in cyanobacteria-dominated hypoliths, a layered spatial organization was structured by filamentous cyanobacteria and associated extracellular polymeric components. While moss cells were lacking in cyanobacteria-dominated communities, biofilms formed by cyanobacteria and heterotrophic bacteria were observed in both community morphotypes. The waterholding capacity of both live and dead moss cells and the associated organic matrix, together with the protective properties of the extracellular polymeric substances, could facilitate the survival and activity of these communities. Similar structural strategies can favour the survival of microbial communities in different extreme environments.

show abstract

The ecology of sublithic terrestrial algae at the Vestfold Hills, Antarctica

Cited by 71 publications

References 6 publications

Cryptic microbial communities in Antarctic deserts

Cryptic microbial communities in Antarctic deserts

Distribution and abiotic influences on hypolithic microbial communities in an Antarctic Dry Valley

The spatial structures of hypolithic communities in the Dry Valleys of East Antarctica

Contact Info

Product

Resources

About