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.
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.
此資料的發布者及權利單位為 SCAR - Microbial Antarctic Resource System。 This work is licensed under a Creative Commons Attribution Non Commercial (CC-BY-NC) 4.0 License.
Bacteria; Cyanobacteria; Fungi; Terrestrial Antarctica; McMurdo Dry Valleys; 16S rRNA; Soil; Metadata
The McMurdo Dry Valleys
|界定座標範圍||緯度南界 經度西界 [-78.091, 160.764], 緯度北界 經度東界 [-76.912, 163.809]|
Molecular surveys of bacterial (16S rRNA) and fungal (ITS) marker genes
|起始日期 / 結束日期||2006-12-01 / 2006-12-31|
|起始日期 / 結束日期||2008-01-01 / 2008-01-31|
|起始日期 / 結束日期||2010-11-01 / 2010-11-30|
|計畫名稱||Inter-Valley Soil Comparative Survey of the McMurdo Dry Valleys|
|經費來源||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.|
|研究區域描述||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.|
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.
|研究範圍||See Geographic Coverage|
|品質控管||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.|
- Two MICROBIAL_SEQUENCE_SET description files describing X data sets was uploaded to the IPT. X MIMARKS data files were uploaded to the IPT.
|蒐藏名稱||Soil Samples from McMurdo Dry Valleys, Antarctica|
- 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