Recent applications of molecular genetics to edaphic microbial communities of the McMurdo Dry Valleys and elsewhere have rejected a long-held belief that Antarctic soils contain extremely limited microbial diversity. The Inter-Valley Soil Comparative Survey aims to elucidate the factors shaping these unique microbial communities and their biogeography by integrating molecular genetic approaches with biogeochemical analyses. Although the microbial communities of Dry Valley soils may be complex, there is little doubt that the ecosystem’s food web is relatively simple, and evidence suggests that physicochemical conditions may have the dominant role in shaping microbial communities. To examine this hypothesis, bacterial communities from representative soil samples collected in four geographically disparate Dry Valleys were analyzed using molecular genetic tools, including pyrosequencing of 16S rRNA gene PCR amplicons. Results show that the four communities are structurally and phylogenetically distinct, and possess significantly different levels of diversity. Strikingly, only 2 of 214 phylotypes were found in all four valleys, challenging a widespread assumption that the microbiota of the Dry Valleys is composed of a few cosmopolitan species. Analysis of soil geochemical properties indicated that salt content, alongside altitude and Cu2+, was significantly correlated with differences in microbial communities. Our results indicate that the microbial ecology of Dry Valley soils is highly localized and that physicochemical factors potentially have major roles in shaping the microbiology of ice-free areas of Antarctica. These findings hint at links between Dry Valley glacial geomorphology and microbial ecology, and raise previously unrecognized issues related to environmental management of this unique ecosystem.
Le tableau ci-dessous n'affiche que les versions publiées de la ressource accessibles publiquement.
Les chercheurs doivent citer cette ressource comme suit:
Lee CK, Barbier BA, Bottos EM, McDonald IR, Cary SC (2012) The Inter-Valley Soil Comparative Survey: the ecology of Dry Valley edaphic microbial communities. ISME J 6: 1046–1057. doi:10.1038/ismej.2011.170.
Les chercheurs doivent respecter la déclaration de droits suivante:
L’éditeur et détenteur des droits de cette ressource est SCAR - Microbial Antarctic Resource System. Ce travail est sous licence Creative Commons Attribution Non Commercial (CC-BY-NC) 4.0.
Cette ressource a été enregistrée sur le portail GBIF, et possède l'UUID GBIF suivante : cca539d1-3e43-49bb-8e1f-8c1bda934a8c. SCAR - Microbial Antarctic Resource System publie cette ressource, et est enregistré dans le GBIF comme éditeur de données avec l'approbation du Scientific Committee on Antarctic Research.
Bacteria; Cyanobacteria; Fungi; Terrestrial Antarctica; McMurdo Dry Valleys; 16S rRNA; Soil; Metadata
- Chercheur Principal
The McMurdo Dry Valleys
|Enveloppe géographique||Sud Ouest [-78,091, 160,764], Nord Est [-76,912, 163,809]|
Molecular surveys of bacterial (16S rRNA) and fungal (ITS) marker genes
|Date de début / Date de fin||2006-12-01 / 2006-12-31|
|Date de début / Date de fin||2008-01-01 / 2008-01-31|
|Date de début / Date de fin||2010-11-01 / 2010-11-30|
Données sur le projet
Pas de description disponible
|Titre||Inter-Valley Soil Comparative Survey of the McMurdo Dry Valleys|
|Financement||Funding was provided by the New Zealand Foundation for Research, Science and Technology (FRST) (UOWX0715) and the New Zealand Marsden Fund (UOW1003). Logistics support was provided by Antarctica New Zealand.|
|Description du domaine d'étude / de recherche||Soil was collected at six different sites in the McMurdo Dry Valleys: Alatna Valley, Battleship Promontory, Upper Wright Valley, Beacon Valley, University Valley, and Miers Valley.|
Les personnes impliquées dans le projet:
- Chercheur Principal
Sampling sites were all located on a south facing, 0–20°slope. An intersection was made by two 50 m transects, with the intersection in the middle being the central sampling point (X or C). Four sampling points around the central point were marked (A–D with A being the southernmost point and the remaining points in an anti-clockwise order, or N, E, S, W). Five scoops of the top 2 cm of soil were collected and homogenized at each identified (1 m2) sampling point after pavement pebbles were removed. Samples were stored in sterile Whirl-Pak (Nasco International, Fort Atkinson, WI, USA) at −20 °C until returned to New Zealand, where they were stored at −80 °C until analysis.
|Etendue de l'étude||See Geographic Coverage|
|Contrôle qualité||454 pyrosquencing flowgrams were denoised using AmpliconNoise, including a SeqNoise step to remove PCR errors and a Perseus step to remove PCR chimeras. See Lee et al 2012 and Dreesens et al 2014 for details.|
Description des étapes de la méthode:
- Two MICROBIAL_SEQUENCE_SET description files describing X data sets was uploaded to the IPT. X MIMARKS data files were uploaded to the IPT.
Données de collection
|Nom de la collection||Soil Samples from McMurdo Dry Valleys, Antarctica|
|Identifiant de collection||N/A|
|Identifiant de la collection parente||N/A|
|Méthode de conservation des spécimens||Deep frozen|
- Dreesens L, Lee CK, Cary SC (2014) The Distribution and Identity of Edaphic Fungi in the McMurdo Dry Valleys. Biology 3: 466–483. doi:10.3390/biology3030466. 10.3390/biology3030466