{"dp_type": "Dataset", "free_text": "Cell Counts"}
[{"awards": "1744871 Robinson, Rebecca", "bounds_geometry": null, "date_created": "Wed, 30 Aug 2023 00:00:00 GMT", "description": "This dataset is the results of 3 experiments in which the spore-forming diatom Chaetoceros socialis was grown in culture and induced into resting spores by nitrate limitation. The nitrogen isotopic composition of accumulated biomass (\u03b415Nbiomass; \u2030 vs air) and of diatom-bound organic N (\u03b415Ndb; \u2030 vs air) are reported at two timepoints from each experiment: prior to and after resting spore formation. Experiments 1 and 2 provide measurements for CRS mixed with vegetative Chaetoceros cells, while Experiment 3 provides measurements for isolated CRS. Fluorescence and nitrate concentration was tracked throughout each experiment, with dissolved silica, ammonium, and total reduced nitrogen also measured in Experiment 3.", "east": null, "geometry": null, "keywords": "Antarctica", "locations": "Antarctica; Antarctica", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Dove, Isabel", "project_titles": "The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information?", "projects": [{"proj_uid": "p0010234", "repository": "USAP-DC", "title": "The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information?"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Dissolved nutrients, cell counts, and nitrogen isotope measurements from Chaetoceros socialis culture experiments", "uid": "601727", "west": null}, {"awards": "1543537 Priscu, John", "bounds_geometry": ["POINT(-149.50134 -84.640287)"], "date_created": "Wed, 01 Feb 2023 00:00:00 GMT", "description": "This dataset contains water column biogeochemical properties measured on discrete samples collected from Mercer Subglacial Lake by the SALSA project. Data included are: specific conductance; carbonic acid system parameters (total alkalinity, total inorganic carbon, and pH); water stable isotopes (\u03b42H and \u03b418O); dissolved gases (oxygen, methane, nitrous oxide, and hydrogen); dissolved nutrients (ammonium, nitrite and phosphate), major anions (including nitrate) and cations; size-fractionated colloidal and dissolved trace elements); dissolved organic carbon; and microbial cell and virus-like particle counts.", "east": -149.50134, "geometry": ["POINT(-149.50134 -84.640287)"], "keywords": "Antarctica; Carbon; Cell Counts; Geochemistry; Glacier; Glaciers/ice Sheet; Glaciers/Ice Sheet; Mercer Subglacial Lake; Microbes; Nutrients; SALSA; Stable Isotopes; Trace Elements; West Antarctic Ice Sheet", "locations": "Mercer Subglacial Lake; Mercer Subglacial Lake; West Antarctic Ice Sheet; Antarctica", "north": -84.640287, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Dore, John; Skidmore, Mark; Hawkings, Jon; Steigmeyer, August; Li, Wei; Barker, Joel; Tranter, Martyn; Priscu, John; Science Team, SALSA", "project_titles": "Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments", "projects": [{"proj_uid": "p0010119", "repository": "USAP-DC", "title": "Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -84.640287, "title": "Water column biogeochemical data from Mercer Subglacial Lake", "uid": "601663", "west": -149.50134}, {"awards": "0839075 Priscu, John", "bounds_geometry": ["POINT(-112 -79)"], "date_created": "Tue, 12 Dec 2017 00:00:00 GMT", "description": "This data set includes raw concentration of prokaryotic cells for the WAIS Divide deep core, WDC06A, from 1,764 m to 2,709 m. Data were collected by a method that combines acquisition of discrete samples using a continuous ice-core melting system (McConnell et al., 2002) coupled with flow cytometry of DNA-stained samples. The method is described in detail in Santibanez et al., 2016. \r\r\nWe present the first long-term, highly resolved prokaryotic cell concentration record obtained from a polar ice core. This record, obtained from the West Antarctic Ice Sheet (WAIS) Divide (WD) ice core, spanned from the Last Glacial Maximum (LGM) to the early Holocene (EH) and showed distinct fluctuations in prokaryotic cell concentration coincident with major climatic states. This record provided strong evidence that airborne prokaryotic cell deposition differed during the LGM, LDG and EH, and that these changes in cell densities could be explained by different environmental conditions during each of these climatic periods. Our observations provide the first ice core time-series evidence for a prokaryotic response to long-term climatic and environmental processes.", "east": -112.0, "geometry": ["POINT(-112 -79)"], "keywords": "Antarctica; Biota; Cell Counts; Glaciology; Microbiology; WAIS Divide; WAIS Divide Ice Core", "locations": "WAIS Divide; Antarctica", "north": -79.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Santibanez, Pamela; Priscu, John", "project_titles": "Collaborative Research: Integrated High Resolution Chemical and Biological Measurements on the Deep WAIS Divide Core", "projects": [{"proj_uid": "p0000273", "repository": "USAP-DC", "title": "Collaborative Research: Integrated High Resolution Chemical and Biological Measurements on the Deep WAIS Divide Core"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.0, "title": "Prokaryotic cell concentration record from the WAIS Divide ice core", "uid": "601072", "west": -112.0}, {"awards": "0739648 Cary, Stephen", "bounds_geometry": ["POINT(163 -77.5)"], "date_created": "Tue, 01 Jan 2013 00:00:00 GMT", "description": "The glacial streams of the McMurdo Dry Valleys have extensive cyanobacterial mats that are a probable source of fixed C and N to the Valleys. The research will examine the interplay between the microbial mats in the ephemeral glacial streams and the microbiota of the hyporheic soils (wetted soil zone) underlying and adjacent to those mats. It is hypothesized that the mats are important sources of organic carbon and fixed nitrogen for the soil communities of the hyporheic zone, and release dissolved organic carbon (DOC) and nitrogen (DON) that serves the entire Dry Valley ecosystem. Field efforts will entail both observational and experimental components. Direct comparisons will be made between the mats and microbial populations underlying naturally rehydrated and desiccated mat areas, and between mat areas in the melt streams of the Adams and Miers Glaciers in Miers Valley. Both physiological and phylogenetic indices of the soil microbiota will be examined. Observations will include estimates of rates of mat carbon and nitrogen fixation, soil respiration and leucine and thymidine uptake (as measures of protein \u0026 DNA synthesis, respectively) by soil bacteria, bacterial densities and their molecular ecology. Experimental manipulations will include experimental re-wetting of soils and observations of the time course of response of the microbial community. The research will integrate modern molecular genetic approaches (ARISA-DNA fingerprinting and ultra deep 16S rDNA microbial phylogenetic analysis) with geochemistry to study the diversity, ecology, and function of microbial communities that thrive in these extreme environments. The broader impacts of the project include research and educational opportunities for graduate students and a postdoctoral associate. The P.I.s will involve undergraduates as work-study students and in REU programs, and will participate in educational and outreach programs.", "east": 163.0, "geometry": ["POINT(163 -77.5)"], "keywords": "Antarctica; Biota; Cell Counts; Dry Valleys; Microbiology", "locations": "Dry Valleys; Antarctica", "north": -77.5, "nsf_funding_programs": null, "persons": "Cary, S. Craig", "project_titles": "Collaborative Research: Biogeochemistry of Cyanobactrial Mats and Hyporheic Zone Microbes in McMurdo Dry Valley Glacial Meltwater Streams", "projects": [{"proj_uid": "p0000476", "repository": "USAP-DC", "title": "Collaborative Research: Biogeochemistry of Cyanobactrial Mats and Hyporheic Zone Microbes in McMurdo Dry Valley Glacial Meltwater Streams"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.5, "title": "Biogeochemistry of Cyanobactrial Mats and Hyporheic Zone Microbes in McMurdo Dry Valley Glacial Meltwater Streams", "uid": "600079", "west": 163.0}]
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| Dataset Title/Abstract/Map | NSF Award(s) | Date Created | PIs / Scientists | Project Links | Abstract | Bounds Geometry | Geometry | Selected | Visible |
|---|---|---|---|---|---|---|---|---|---|
|
Dissolved nutrients, cell counts, and nitrogen isotope measurements from Chaetoceros socialis culture experiments
|
1744871 |
2023-08-30 | Dove, Isabel |
The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information? |
This dataset is the results of 3 experiments in which the spore-forming diatom Chaetoceros socialis was grown in culture and induced into resting spores by nitrate limitation. The nitrogen isotopic composition of accumulated biomass (δ15Nbiomass; ‰ vs air) and of diatom-bound organic N (δ15Ndb; ‰ vs air) are reported at two timepoints from each experiment: prior to and after resting spore formation. Experiments 1 and 2 provide measurements for CRS mixed with vegetative Chaetoceros cells, while Experiment 3 provides measurements for isolated CRS. Fluorescence and nitrate concentration was tracked throughout each experiment, with dissolved silica, ammonium, and total reduced nitrogen also measured in Experiment 3. | [] | [] | false | false |
|
Water column biogeochemical data from Mercer Subglacial Lake
|
1543537 |
2023-02-01 | Dore, John; Skidmore, Mark; Hawkings, Jon; Steigmeyer, August; Li, Wei; Barker, Joel; Tranter, Martyn; Priscu, John; Science Team, SALSA |
Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments |
This dataset contains water column biogeochemical properties measured on discrete samples collected from Mercer Subglacial Lake by the SALSA project. Data included are: specific conductance; carbonic acid system parameters (total alkalinity, total inorganic carbon, and pH); water stable isotopes (δ2H and δ18O); dissolved gases (oxygen, methane, nitrous oxide, and hydrogen); dissolved nutrients (ammonium, nitrite and phosphate), major anions (including nitrate) and cations; size-fractionated colloidal and dissolved trace elements); dissolved organic carbon; and microbial cell and virus-like particle counts. | ["POINT(-149.50134 -84.640287)"] | ["POINT(-149.50134 -84.640287)"] | false | false |
|
Prokaryotic cell concentration record from the WAIS Divide ice core
|
0839075 |
2017-12-12 | Santibanez, Pamela; Priscu, John |
Collaborative Research: Integrated High Resolution Chemical and Biological Measurements on the Deep WAIS Divide Core |
This data set includes raw concentration of prokaryotic cells for the WAIS Divide deep core, WDC06A, from 1,764 m to 2,709 m. Data were collected by a method that combines acquisition of discrete samples using a continuous ice-core melting system (McConnell et al., 2002) coupled with flow cytometry of DNA-stained samples. The method is described in detail in Santibanez et al., 2016. We present the first long-term, highly resolved prokaryotic cell concentration record obtained from a polar ice core. This record, obtained from the West Antarctic Ice Sheet (WAIS) Divide (WD) ice core, spanned from the Last Glacial Maximum (LGM) to the early Holocene (EH) and showed distinct fluctuations in prokaryotic cell concentration coincident with major climatic states. This record provided strong evidence that airborne prokaryotic cell deposition differed during the LGM, LDG and EH, and that these changes in cell densities could be explained by different environmental conditions during each of these climatic periods. Our observations provide the first ice core time-series evidence for a prokaryotic response to long-term climatic and environmental processes. | ["POINT(-112 -79)"] | ["POINT(-112 -79)"] | false | false |
|
Biogeochemistry of Cyanobactrial Mats and Hyporheic Zone Microbes in McMurdo Dry Valley Glacial Meltwater Streams
|
0739648 |
2013-01-01 | Cary, S. Craig |
Collaborative Research: Biogeochemistry of Cyanobactrial Mats and Hyporheic Zone Microbes in McMurdo Dry Valley Glacial Meltwater Streams |
The glacial streams of the McMurdo Dry Valleys have extensive cyanobacterial mats that are a probable source of fixed C and N to the Valleys. The research will examine the interplay between the microbial mats in the ephemeral glacial streams and the microbiota of the hyporheic soils (wetted soil zone) underlying and adjacent to those mats. It is hypothesized that the mats are important sources of organic carbon and fixed nitrogen for the soil communities of the hyporheic zone, and release dissolved organic carbon (DOC) and nitrogen (DON) that serves the entire Dry Valley ecosystem. Field efforts will entail both observational and experimental components. Direct comparisons will be made between the mats and microbial populations underlying naturally rehydrated and desiccated mat areas, and between mat areas in the melt streams of the Adams and Miers Glaciers in Miers Valley. Both physiological and phylogenetic indices of the soil microbiota will be examined. Observations will include estimates of rates of mat carbon and nitrogen fixation, soil respiration and leucine and thymidine uptake (as measures of protein & DNA synthesis, respectively) by soil bacteria, bacterial densities and their molecular ecology. Experimental manipulations will include experimental re-wetting of soils and observations of the time course of response of the microbial community. The research will integrate modern molecular genetic approaches (ARISA-DNA fingerprinting and ultra deep 16S rDNA microbial phylogenetic analysis) with geochemistry to study the diversity, ecology, and function of microbial communities that thrive in these extreme environments. The broader impacts of the project include research and educational opportunities for graduate students and a postdoctoral associate. The P.I.s will involve undergraduates as work-study students and in REU programs, and will participate in educational and outreach programs. | ["POINT(163 -77.5)"] | ["POINT(163 -77.5)"] | false | false |
