Characterization of 15 selected coccal bacteria isolated from antarctic rock and soil samples from the McMurdo-Dry Valleys (South-Victoria Land)

Lake Wilson, a perennially ice-capped, deep (>100 m) lake at 80°S in southern Victoria Land was investigated in January 1993. Water chemistry and physical structure showed three distinct layers; an upper c. 35 m mixed layer of low salinity, moderately turbid water; a less turbid mid layer, 20 m thick of slightly higher salinity and supersaturated with oxygen; and a deep 20 m brackish layer (conductivity c. 4000 μS cm−1) with anoxic conditions in the lower 5 m. Extreme supersaturation of N2O (up to 400 times air saturation) together with high nitrate concentration (4000 mg m−3) was recorded in the deep layer. Phytoplankton biomass and photosynthetic activity was confined to the upper mixed layer and the band of supersaturated dissolved oxygen located at 40–55 m appears to represent a relict layer from when the lake level was lower. The evidence from a comparison of profiles between 1975 and 1993 suggests that Lake Wilson has risen 25 m since 1975, synchronous with a period of lake level rise in the McMurdo Dry Valleys lakes to the north at 77°S. Geochemical diffusion models indicate that Lake Wilson had evaporated to a smaller brine lake about 1000 yrs BP, which also fits the pattern shown by the McMurdo Dry Valleys lakes. Climate changes influencing lake levels have thus covered a wide area of southern Victoria Land.

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A Late Holocene desiccation of Lake Hoare and Lake Fryxell, McMurdo Dry Valleys, Antarctica

Antarctic Science ◽

10.1017/s0954102098000340 ◽

1998 ◽

Vol 10 (3) ◽

pp. 247-256 ◽

Cited By ~ 71

Author(s):

W.B. Lyons ◽

S.W. Tyler ◽

R.A. Wharton ◽

D.M. McKnight ◽

B.H. Vaughn

Keyword(s):

Late Holocene ◽

Mcmurdo Dry Valleys ◽

Published Data ◽

Dry Valleys ◽

Humid Climate ◽

The Past ◽

Victoria Land ◽

History Of ◽

Lake Fryxell ◽

Climatic History

Stable isotope data from waters of lakes in the McMurdo Dry Valleys (MDV) of southern Victoria Land, Antarctica are presented in order to establish the climatic history of this region over the past two millennia. New data from Lake Fryxell and Lake Hoare in Toylor Valley, along with previously published data from Lake Vanda, Wright Valley and Lake Bonney, Taylor Valley are used to infer the recent climatic history of MDV. Lakes Vanda, Fryxell and Bonney appear to have lost their ice covers and evaporated to small, hypersaline ponds by 1000 to ~1200 yr BP. Lake Hoare either desiccated or did not exist prior to 1200 yr BP. These data indicate a major lowering of lake level prior to ~1000 yr BP, followed by a warmer and/or more humid climate since then.

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Twenty-seventh Antarctic Treaty Consultative Meeting Cape Town, South Africa, 24 May–4 June 2004

Polar Record ◽

10.1017/s0032247404004012 ◽

2005 ◽

Vol 41 (1) ◽

pp. 77-96 ◽

Cited By ~ 1

Keyword(s):

South Africa ◽

Cape Town ◽

Management Plan ◽

Mcmurdo Dry Valleys ◽

Dry Valleys ◽

Victoria Land ◽

Antarctic Treaty ◽

The Antarctic

The texts of the Decisions and Resolutions, and the text of Measure 1 (2004), together with a summary of the Management Plan for Antarctic Specially Managed area No. 2, McMurdo Dry Valleys, Southern Victoria Land, adopted at XXVII ATCM were reproduced in SCAR Bulletin No 155, October 2004. A summary of the Management Plan for Antarctic Specially Managed Area No. 3, Cape Denison, Commonwealth Bay, George V land, together with Measures 2–4, are reproduced here. The full versions of all the Decisions, Measures and Resolutions are on the Antarctic Treaty Secretariat website at http://www.ats.org.ar/

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Geochemical characterization of fluoride in water, table salt, active sediment, rock and soil samples, and its possible relationship with the prevalence of enamel fluorosis in children in four municipalities of the department of Huila (Colombia)

Environmental Monitoring and Assessment ◽

10.1007/s10661-017-5975-6 ◽

2017 ◽

Vol 189 (6) ◽

Cited By ~ 1

Author(s):

Stefania Martignon ◽

Mario Omar Opazo-Gutiérrez ◽

Möritz Velásquez-Riaño ◽

Iván Rodrigo Orjuela-Osorio ◽

Viviana Avila ◽

...

Keyword(s):

Water Table ◽

Soil Samples ◽

Table Salt ◽

Geochemical Characterization ◽

Rock And Soil

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Experimental formation of pore fluids in McMurdo Dry Valleys soils

Antarctic Science ◽

10.1017/s0954102014000479 ◽

2014 ◽

Vol 27 (2) ◽

pp. 163-171 ◽

Cited By ~ 3

Author(s):

Joseph Levy ◽

Andrew Fountain ◽

W. Berry Lyons ◽

Kathy Welch

Keyword(s):

Relative Humidity ◽

Salt Content ◽

Soil Samples ◽

Mcmurdo Dry Valleys ◽

Absolute Amount ◽

Dry Valleys ◽

Pore Waters ◽

Taylor Valley ◽

Experimental Formation ◽

Laboratory Analogue

AbstractThe aim of the study was to determine if soil salt deliquescence and brine hydration can occur under laboratory conditions using natural McMurdo Dry Valleys soils. The experiment was a laboratory analogue for the formation of isolated patches of hypersaline, damp soil, referred to as ‘wet patches’. Soils were oven dried and then hydrated in one of two humidity chambers: one at 100% relative humidity and the second at 75% relative humidity. Soil hydration is highly variable, and over the course of 20 days of hydration, ranged from increases in water content by mass from 0–16% for 122 soil samples from Taylor Valley. The rate and absolute amount of soil hydration correlates well with the soluble salt content of the soils but not with grain size distribution. This suggests that the formation of bulk pore waters in these soils is a consequence of salt deliquescence and hydration of the brine from atmospheric water vapour.

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Extreme southern locations for moss sporophytes in Antarctica

Antarctic Science ◽

10.1017/s0954102092000087 ◽

1992 ◽

Vol 4 (1) ◽

pp. 37-39 ◽

Cited By ~ 23

Author(s):

R.D. Seppelt ◽

T.G.A. Green ◽

A-M.J. Schwarz ◽

A. Frost

Keyword(s):

Mcmurdo Dry Valleys ◽

Dry Valleys ◽

Southern Limit ◽

Taylor Valley ◽

Victoria Land

Abundant immature sporophytes of the moss Pottia heimii are reported from the Lower Taylor Valley, McMurdo Dry Valleys and from Cape Chocolate, Victoria Land. These finds extend the reported southern limit for the occurrence of abundant moss sporophytes to 77° 55′S.

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