Perennial Antarctic Lake Ice: An Oasis for Life in a Polar Desert

Priscu, John C.; Fritsen, Christian H.; Adams, Edward; Giovannoni, Stephen J.; Paerl, Hans W.; McKay, Christopher P.; Doran, Peter T.; Gordon, Douglas A.; Lanoil, Brian; Pinckney, James L.

doi:10.1126/science.280.5372.2095

Cited by 341 publications

(217 citation statements)

References 14 publications

Supporting

Mentioning

208

Contrasting

Unclassified

Order By: Relevance

“…This is consistent with the findings of , who also showed that the net primary productivity (inferred from oxygen evolution rates) in C. simplex was highest in pelagic and lowest in sea-ice conditions during short-term acclimation experiments. The results are also consistent with in-situ measurements from an Antarctic ice-covered lake (Priscu et al, 1998). Further, thẽ 8-fold difference in carbon productivity rates between cells from the sea-ice and pelagic treatments is almost identical to that measured by Boyd et al (1995), where carbon productivity rates in sea-ice algae were eight times lower than those in the surrounding water column.…”

Section: Discussionsupporting

confidence: 86%

Snapshot prediction of carbon productivity, carbon and protein content in a Southern Ocean diatom using FTIR spectroscopy

et al. 2015

View full text Add to dashboard Cite

Diatoms, an important group of phytoplankton, bloom annually in the Southern Ocean, covering thousands of square kilometers and dominating the region's phytoplankton communities. In their role as the major food source to marine grazers, diatoms supply carbon, nutrients and energy to the Southern Ocean food web. Prevailing environmental conditions influence diatom phenotypic traits (for example, photophysiology, macromolecular composition and morphology), which in turn affect the transfer of energy, carbon and nutrients to grazers and higher trophic levels, as well as oceanic biogeochemical cycles. The paucity of phenotypic data on Southern Ocean phytoplankton limits our understanding of the ecosystem and how it may respond to future environmental change. Here we used a novel approach to create a 'snapshot' of cell phenotype. Using mass spectrometry, we measured nitrogen (a proxy for protein), total carbon and carbon-13 enrichment (carbon productivity), then used this data to build spectroscopy-based predictive models. The models were used to provide phenotypic data for samples from a third sample set. Importantly, this approach enabled the first ever rate determination of carbon productivity from a single time point, circumventing the need for timeseries measurements. This study showed that Chaetoceros simplex was less productive and had lower protein and carbon content during short-term periods of high salinity. Applying this new phenomics approach to natural phytoplankton samples could provide valuable insight into understanding phytoplankton productivity and function in the marine system.

show abstract

Section: Discussionsupporting

confidence: 86%

Snapshot prediction of carbon productivity, carbon and protein content in a Southern Ocean diatom using FTIR spectroscopy

et al. 2015

View full text Add to dashboard Cite

show abstract

“…Long regarded as essentially barren of life, recent investigations of Antarctic environments have revealed considerable microbial activity (e.g. Priscu et al 1998). The Archaea and Bacteria that have adapted to these extreme conditions are some of the best candidates for terrestrial analogues of potential extraterrestrial life; understanding their adaptive strategy, and its limitations, will provide deeper insight into fundamental constraints on the range of habitable environments (Cavicchioli 2002;DasSarma 2006).…”

Section: Introductionmentioning

confidence: 99%

Terrestrial models for extraterrestrial life: methanogens and halophiles at Martian temperatures

Reid¹,

Sparks²,

Lubow³

et al. 2006

International Journal of Astrobiology

View full text Add to dashboard Cite

: Cold environments are common throughout the Galaxy. We are conducting a series of experiments designed to probe the low-temperature limits for growth in selected methanogenic and halophilic Archaea. This paper presents initial results for two mesophiles, a methanogen, Methanosarcina acetivorans, and a halophile, Halobacterium sp. NRC-1, and for two Antarctic coldadapted Archaea, a methanogen, Methanococcoides burtonii, and a halophile, Halorubrum lacusprofundi. Neither mesophile is active at temperatures below 5 xC, but both cold-adapted microorganisms show significant growth at sub-zero temperatures (x2 xC and x1 xC, respectively), extending previous lowtemperature limits for both species by 4-5 xC. At low temperatures, both H. lacusprofundi and M. burtonii form multicellular aggregates, which appear to be embedded in extracellular polymeric substances. This is the first detection of this phenomenon in Antarctic species of Archaea at cold temperatures. The low-temperature limits for both psychrophilic species fall within the temperature range experienced on present-day Mars and could permit survival and growth, particularly in subsurface environments. We also discuss the results of our experiments in the context of known exoplanet systems, several of which include planets that intersect the Habitable Zone. In most cases, those planets follow orbits with significant eccentricity, leading to substantial temperature excursions. However, a handful of the known gas giant exoplanets could potentially harbour habitable terrestrial moons.

show abstract

“…Multidisciplinary approaches have been undertaken to investigate relevant cyanobacteria and algae from various sources including polar desert (Priscu et al, 1998). The taxonomic features, physiological properties and ecological adaptation of these organisms as well as the potentiality to use them in desert reclamation have been discussed (Garcia-Pichel et al, 2001;Liu et al, 2001;Potts, 2000).…”

Section: Introductionmentioning

confidence: 99%

The vertical microdistribution of cyanobacteria and green algae within desert crusts and the development of the algal crusts

et al. 2003

View full text Add to dashboard Cite

Substantial amounts of algal crusts were collected from five different desert experimental sites aged 42, 34, 17, 8 and 4 years, respectively, at Shapotou (China) and analyzed at a 0.1 mm microscale of depth. It was found that the vertical distribution of cyanobacteria and microalgae in the crusts was distinctly laminated into an inorganic-layer (ca.0.00-0.02 mm, with few algae), an algae-dense-layer (ca.0.02-1.0 mm) and an algae-sparselayer (ca.1.0-5.0 mm). It was interesting to note that in all crusts Scytonema javanicum Born et Flah (or Nostoc sp., cyanobacterium), Desmococcus olivaceus (Pers ex Ach., green alga) Laundon and Microcoleus vaginatus Gom. (cyanobacterium) dominated at the depth of 0.02-0.05, 0.05-0.1 and 0.1-1.0 mm, respectively, from the surface. Phormidium tenue Gom. (or Lyngbya cryptovaginatus Schk., cyanobacterium) and Navicula cryptocephala Kutz.(or Hantzschia amphioxys (Ehr.) Grun. and N. cryptocephala together, diatom) dominated at the depth of 1.0-3.0 and 3.5-4.0 mm, respectively, of the crusts from the 42 and 34 year old sites. It was apparent that in more developed crusts there were more green algae and the niches of Nostoc sp., Chlorella vulgaris Beij., M. vaginatus, N. cryptocephala and fungi were nearer to the surface. If lichens and mosses accounted for less than 41.5% of the crust surface, algal biovolume was bigger when the crust was older, but the opposite was true when the cryptogams other than algae covered more than 70%. In addition to detailed species composition and biovolume, analyses of soil physicochemical properties, micromorphologies and mineral components were also performed. It was found that the concentration of organic matter and nutrients, electric conductivity, silt, clay, secondary minerals were higher and there were more micro-beddings in the older crusts than the less developed ones. Possible mechanisms for the algal vertical microdistribtion at different stages and the impact of soil topography on crust development are discussed. It is concluded that biomethods (such as fine species distribution and biovolume) were more precise than mineralogical approaches in judging algal crust development and thus could be a better means to measure the potentiality of algal crusts in desert amelioration.Abbreviations: I.V. -Important Value; PLM -Polarizing Light Microscope; SEM -Scanning Electron Microscopy

show abstract

Perennial Antarctic Lake Ice: An Oasis for Life in a Polar Desert

Cited by 341 publications

References 14 publications

Snapshot prediction of carbon productivity, carbon and protein content in a Southern Ocean diatom using FTIR spectroscopy

Snapshot prediction of carbon productivity, carbon and protein content in a Southern Ocean diatom using FTIR spectroscopy

Terrestrial models for extraterrestrial life: methanogens and halophiles at Martian temperatures

The vertical microdistribution of cyanobacteria and green algae within desert crusts and the development of the algal crusts

Contact Info

Product

Resources

About