Sedimentation in ice‐covered Lake Hoare, Antarctica

Nedell, Susan S.; Andersen, David W.; Squyres, S. W.; Love, F. Gordon

doi:10.1111/j.1365-3091.1987.tb00594.x

Cited by 60 publications

(47 citation statements)

References 10 publications

(7 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Sediment coalescence into clumps and layers may enhance melt-migration by increasing shortwave absorption and thermally insulating grains from ice. This may account for the discrepancy between studies showing that sediment melts effectively through lake ice (this study; and studies suggesting that sediment melt-migration is inhibited by thermal contact between ice and individual grains (Simmons et al, 1986;Nedell et al, 1987;Wharton et al, 1993).…”

Section: Discussioncontrasting

confidence: 50%

“…These dimensions are similar to those in the ice covers of Lakes Bonney Priscu et al, 1998) and Hoare (Nedell et al, 1987;Squyres et al, 1991). Sediment coalescence into clumps and layers may enhance melt-migration by increasing shortwave absorption and thermally insulating grains from ice.…”

Section: Discussionsupporting

confidence: 49%

“…Transport to deeper ice requires the presence of fractures or conduits (Simmons et al, 1986;Nedell et al, 1987;Squyres et al, 1991). An equilibrium depth of 2 m compares well with published depths of accumulated sediment in the ice covers of Lakes Bonney and Hoare (Nedell et al, 1987;Squyres et al, 1991). However, this depth exceeds values observed at Lake Fryxell, where sediment accumulates in the upper 0.5 m of ice Priscu et al, 2005).…”

Section: Discussionmentioning

confidence: 99%

“…Much of the lake floor sediment in the dry valleys originated as eolian deposits that migrated through the ice covers by melting and settling along fractures and conduits Simmons et al, 1986;Nedell et al, 1987;Squyres et al, 1991). Lancaster (2002) reported an eolian sediment flux of 1 g m 22 yr 21 on the ice of Lake Fryxell, of which 89% (by mass) was mud and 11% was sand.…”

mentioning

confidence: 99%

See 3 more Smart Citations

Sediment Melt-Migration Dynamics in Perennial Antarctic Lake Ice

Jepsen¹,

Adams

Priscu

2010

Arctic, Antarctic, and Alpine Research

View full text Add to dashboard Cite

Section: Discussioncontrasting

confidence: 50%

Section: Discussionsupporting

confidence: 49%

Section: Discussionmentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Sediment Melt-Migration Dynamics in Perennial Antarctic Lake Ice

Jepsen¹,

Adams

Priscu

2010

Arctic, Antarctic, and Alpine Research

View full text Add to dashboard Cite

“…Antarctic lake waters collected in the McMurdo Dry Valleys were studied in-depth, yielding information on the relationship between water chemistry and microorganisms [17,18], paleoclimatology [28], chemical alteration and sedimentation [29,30]. The region of Terra Nova Bay has been studied since 1985, year of the beginning of the Italian National Research Program in Antarctica (P.N.R.A.…”

Section: Introductionmentioning

confidence: 99%

d- and l-amino acids in Antarctic lakes: assessment of a very sensitive HPLC-MS method

et al. 2014

View full text Add to dashboard Cite

Amino acids represent a fraction of organic matter in marine and freshwater ecosystems, and a source of carbon, nitrogen and energy. L-Amino acids are the most common enantiomers in nature because these chiral forms are used during the biosynthesis of proteins and peptide. To the contrary, the occurrence of D-amino acids is usually linked to the presence of bacteria. We investigated the distribution of L-and D-amino acids in the lacustrine environment of Terra Nova Bay, Antarctica, in order to define their natural composition in this area and to individuate a possible relationship with primary production. A simultaneous chromatographic separation of 40 L-and D-amino acids was performed using a chiral stationary phase based on teicoplainin aglycone (CHIROBIOTIC TAG). The chromatographic separation was coupled to two different mass spectrometers-an LTQ-Orbitrap XL (Thermo Fisher Scientific) and an API 4000 (ABSciex)-in order to investigate their quantitative performance. High-performance liquid chromatography coupled with mass spectrometry methods were evaluated through the estimation of their linear ranges, repeatability, accuracy and detection and quantification limits. The high-resolution mass spectrometer LTQ-Orbitrap XL presented detection limits between 0.4 and 7 μgL −1 , while the triple quadrupole mass spectrometer API 4000 achieved the best detection limits reported in the literature for the quantification of amino acids (between 4 and 200 ngL −1 ). The most sensitive method, HPLC-API 4000, was applied to lake water samples.

show abstract

The permanent ice cover of Lake Bonney, Antarctica: The influence of thickness and sediment distribution on photosynthetically available radiation and chlorophyll-a distribution in the underlying water column

Obryk

Doran

Priscu

2014

J. Geophys. Res. Biogeosci.

View full text Add to dashboard Cite

The thick permanent ice cover on the lakes of the McMurdo Dry Valleys, Antarctica, inhibits spatial lake sampling due to logistical constraints of penetrating the ice cover. To date most sampling of these lakes has been made at only a few sites with the assumption that there is a spatial homogeneity of the physical and biogeochemical properties of the ice cover and the water column at any given depth. To test this underlying assumption, an autonomous underwater vehicle (AUV) was deployed in Lake Bonney, Taylor Valley. Measurements were obtained over the course of 2 years in a 100 × 100 m horizontal sampling grid (at a 0.2 m vertical resolution). Additionally, the AUV measured the ice thickness (in water equivalent) and collected images looking up through the ice, which were used to quantify sediment distribution on the surface and within the ice. Satellite imagery was used to map sediment distribution on the surface of the ice. We present results of the spatial investigation of the sediment distribution on the ice cover and its effects on biological processes, with particular emphasis on photosynthetically active radiation (PAR). The surface sediment is a secondary controller of the ice cover thickness, which in turn controls the depth-integrated PAR in the water column. Our data revealed that depth-integrated PAR was negatively correlated with depth-integrated chlorophyll-a (r = 0.88, p < 0.001, n = 83), which appears to be related to short-term photoadaptation of phytoplanktonic communities to spatial and temporal variation in PAR within the water column. IntroductionLake sampling of Antarctic perennially ice-covered lakes is usually limited to only a few sites per year because of the challenge of getting access to the water column. Sampling is usually performed at the deepest part of the lake, which is assumed to represent the entire lake at any given depth. Such an assumption might be valid in temperate lakes due to the seasonal overturning of the water column. However, because of the strong stratification and lack of mixing in the Antarctic lakes [Spigel and Priscu, 1998], biogeochemical horizontal homogeneity of the water column might not exist. The low kinetic energy of the Antarctic lake systems (diffusion dominates the spatial transport of constituents) may produce an ecosystem and ecosystem limits that vary significantly in three dimensions, variations which will not be detected with lake data sets collected at one site at various depths. Spigel and Priscu [1998] have shown spatial and temporal stability of the water column based on 3 years of conductivity and temperature profiles in perennially ice-covered Lake Bonney (Figure 1). However, variations of underwater photosynthetically active radiation (UW PAR) and chlorophyll-a under the ice have not been previously documented in high spatial and temporal resolution.In this paper, we present the results of an investigation by the Environmentally Non-Disturbing Under-ice Robotic ANtarctiC Explorer (ENDURANCE), deployed during the

show abstract

Sedimentation in ice‐covered Lake Hoare, Antarctica

Cited by 60 publications

References 10 publications

Sediment Melt-Migration Dynamics in Perennial Antarctic Lake Ice

Sediment Melt-Migration Dynamics in Perennial Antarctic Lake Ice

d- and l-amino acids in Antarctic lakes: assessment of a very sensitive HPLC-MS method

The permanent ice cover of Lake Bonney, Antarctica: The influence of thickness and sediment distribution on photosynthetically available radiation and chlorophyll-a distribution in the underlying water column

Contact Info

Product

Resources

About