[{"awards": "2336354 Juarez Rivera, Marisol; 1937748 Sumner, Dawn", "bounds_geometry": ["POINT(163.1146 -77.6078)"], "date_created": "Wed, 02 Oct 2024 00:00:00 GMT", "description": "This dataset contains measurements of microbial mat thickness and number of laminae from Lake Fryxell, McMurdo Dry Valleys, Antarctica. Holes were melted through the ice cover of Lake Fryxell, which allowed tethered divers to collect benthic microbial mats (non-liftoff and liftoff) and microbial mats at the ice-water interface (float mats). Benthic non-liftoff and liftoff mat samples were collected from 4.3 m (n=4), 6.1 m (n=4), and 7.9 m (n=4) depths. Float mats were collected from the ice-water interface above 4.3 m (n=4), 6.1 m (n=4), and 7.9 m (n=5) depths. The mats were dissected along vertical cross sections in the field to measure mat thickness and number of laminae. Additional funding for this work was provided by the NASA Solar System Workings Program (Award #80NSSC22K0709).", "east": 163.1146, "geometry": ["POINT(163.1146 -77.6078)"], "keywords": "Antarctica; Cryosphere; Dry Valleys; Lake Fryxell; Laminae; Microbial Mat; Thickness", "locations": "Antarctica; Lake Fryxell; Dry Valleys; Antarctica", "north": -77.6078, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Integrated System Science", "persons": "Juarez Rivera, Marisol; Mackey, Tyler; Hawes, Ian; Paul, Ann; Sumner, Dawn", "project_titles": "RAPID: Is Biomass Mobilization at Ice-covered Lake Fryxell, Antarctica reaching a Critical Threshold?; Seasonal Primary Productivity and Nitrogen Cycling in Photosynthetic Mats, Lake Fryxell, McMurdo Dry Valleys", "projects": [{"proj_uid": "p0010467", "repository": "USAP-DC", "title": "RAPID: Is Biomass Mobilization at Ice-covered Lake Fryxell, Antarctica reaching a Critical Threshold?"}, {"proj_uid": "p0010219", "repository": "USAP-DC", "title": "Seasonal Primary Productivity and Nitrogen Cycling in Photosynthetic Mats, Lake Fryxell, McMurdo Dry Valleys"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.6078, "title": "Lake Fryxell 2022-2023 benthic microbial mat thickness and number of laminae", "uid": "601839", "west": 163.1146}, {"awards": "2044924 Barrett, John", "bounds_geometry": ["POLYGON((161.70776367188 -77.519802097166,161.899475097661 -77.519802097166,162.091186523442 -77.519802097166,162.282897949223 -77.519802097166,162.474609375004 -77.519802097166,162.666320800785 -77.519802097166,162.858032226566 -77.519802097166,163.049743652347 -77.519802097166,163.241455078128 -77.519802097166,163.433166503909 -77.519802097166,163.62487792969 -77.519802097166,163.62487792969 -77.54867059480199,163.62487792969 -77.57753909243799,163.62487792969 -77.606407590074,163.62487792969 -77.63527608771,163.62487792969 -77.664144585346,163.62487792969 -77.69301308298199,163.62487792969 -77.72188158061799,163.62487792969 -77.750750078254,163.62487792969 -77.77961857589,163.62487792969 -77.808487073526,163.433166503909 -77.808487073526,163.241455078128 -77.808487073526,163.049743652347 -77.808487073526,162.858032226566 -77.808487073526,162.666320800785 -77.808487073526,162.474609375004 -77.808487073526,162.282897949223 -77.808487073526,162.091186523442 -77.808487073526,161.899475097661 -77.808487073526,161.70776367188 -77.808487073526,161.70776367188 -77.77961857589,161.70776367188 -77.750750078254,161.70776367188 -77.72188158061799,161.70776367188 -77.69301308298199,161.70776367188 -77.664144585346,161.70776367188 -77.63527608771,161.70776367188 -77.606407590074,161.70776367188 -77.57753909243799,161.70776367188 -77.54867059480199,161.70776367188 -77.519802097166))"], "date_created": "Wed, 03 Apr 2024 00:00:00 GMT", "description": "Microbial communities are the primary drivers of carbon cycling in the McMurdo Dry Valleys of Antarctica. Dense microbial mats, consisting mainly of photosynthetic cyanobacteria, occupy aquatic areas associated with streams and lakes. Other microbial communities also occur at lower densities as patchy surface biological soil crusts (biocrusts) across the terrestrial landscape. Multispectral satellite data have been used to model microbial mat abundance in high-density areas like stream and lake margins, but no previous studies had investigated the lower detection limits of biocrusts. Here, we describe remote sensing and field-based survey and sampling approaches to study the detectability and distribution of biocrusts in the McMurdo Dry Valleys. Using a combination of multi- and hyperspectral tools and spectral linear unmixing, we modeled the abundances of biocrust in eastern Taylor Valley. Our spectral approaches can detect low masses of biocrust material in laboratory microcosms down to biocrust concentrations of 1% by mass. These techniques also distinguish the spectra of biocrust from both surface rock and mineral signatures from orbit. We found that biocrusts are present throughout the soils of eastern Taylor Valley and are associated with diverse underlying soil communities. The densest biocrust communities identified in this study had total organic carbon 5x greater than the content of typical arid soils. The most productive biocrusts were located downslope of melting snowpacks in unique soil ecosystems that are distinct from the surrounding arid landscape. There are similarities between the snowpack and stream sediment communities (high diversity of soil invertebrates) as well as their ecosystem properties (e.g., persistence of liquid water, high transfer of available nutrients, lower salinity from flushing) compared to the typical arid terrestrial ecosystem of the dry valleys. Our approach extends the capability of orbital remote sensing of photosynthetic communities out of the aquatic margins and into the drier soils which comprise most of this landscape. This interdisciplinary work is critical for measuring and monitoring terrestrial carbon stocks and predicting future ecosystem dynamics in this currently water-limited but increasingly dynamic Antarctic landscape, which is particularly climate-sensitive and difficult to access.\r\n", "east": 163.62487792969, "geometry": ["POINT(162.666320800785 -77.664144585346)"], "keywords": "Antarctica; Carbon; Cryosphere; McMurdo Dry Valleys; Snow", "locations": "McMurdo Dry Valleys; Antarctica", "north": -77.519802097166, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "Barrett, John", "project_titles": null, "projects": null, "repositories": null, "science_programs": null, "south": -77.808487073526, "title": "Hyperspectral reflectance values and biophysicochemical properties of biocrusts and soils in the Fryxell Basin, McMurdo Dry Valleys, Antarctica", "uid": "601773", "west": 161.70776367188}, {"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
Lake Fryxell 2022-2023 benthic microbial mat thickness and number of laminae	2336354 1937748	2024-10-02	Juarez Rivera, Marisol; Mackey, Tyler; Hawes, Ian; Paul, Ann; Sumner, Dawn	RAPID: Is Biomass Mobilization at Ice-covered Lake Fryxell, Antarctica reaching a Critical Threshold? Seasonal Primary Productivity and Nitrogen Cycling in Photosynthetic Mats, Lake Fryxell, McMurdo Dry Valleys	This dataset contains measurements of microbial mat thickness and number of laminae from Lake Fryxell, McMurdo Dry Valleys, Antarctica. Holes were melted through the ice cover of Lake Fryxell, which allowed tethered divers to collect benthic microbial mats (non-liftoff and liftoff) and microbial mats at the ice-water interface (float mats). Benthic non-liftoff and liftoff mat samples were collected from 4.3 m (n=4), 6.1 m (n=4), and 7.9 m (n=4) depths. Float mats were collected from the ice-water interface above 4.3 m (n=4), 6.1 m (n=4), and 7.9 m (n=5) depths. The mats were dissected along vertical cross sections in the field to measure mat thickness and number of laminae. Additional funding for this work was provided by the NASA Solar System Workings Program (Award #80NSSC22K0709).	["POINT(163.1146 -77.6078)"]	["POINT(163.1146 -77.6078)"]	false	false
Hyperspectral reflectance values and biophysicochemical properties of biocrusts and soils in the Fryxell Basin, McMurdo Dry Valleys, Antarctica	2044924	2024-04-03	Barrett, John	No project link provided	Microbial communities are the primary drivers of carbon cycling in the McMurdo Dry Valleys of Antarctica. Dense microbial mats, consisting mainly of photosynthetic cyanobacteria, occupy aquatic areas associated with streams and lakes. Other microbial communities also occur at lower densities as patchy surface biological soil crusts (biocrusts) across the terrestrial landscape. Multispectral satellite data have been used to model microbial mat abundance in high-density areas like stream and lake margins, but no previous studies had investigated the lower detection limits of biocrusts. Here, we describe remote sensing and field-based survey and sampling approaches to study the detectability and distribution of biocrusts in the McMurdo Dry Valleys. Using a combination of multi- and hyperspectral tools and spectral linear unmixing, we modeled the abundances of biocrust in eastern Taylor Valley. Our spectral approaches can detect low masses of biocrust material in laboratory microcosms down to biocrust concentrations of 1% by mass. These techniques also distinguish the spectra of biocrust from both surface rock and mineral signatures from orbit. We found that biocrusts are present throughout the soils of eastern Taylor Valley and are associated with diverse underlying soil communities. The densest biocrust communities identified in this study had total organic carbon 5x greater than the content of typical arid soils. The most productive biocrusts were located downslope of melting snowpacks in unique soil ecosystems that are distinct from the surrounding arid landscape. There are similarities between the snowpack and stream sediment communities (high diversity of soil invertebrates) as well as their ecosystem properties (e.g., persistence of liquid water, high transfer of available nutrients, lower salinity from flushing) compared to the typical arid terrestrial ecosystem of the dry valleys. Our approach extends the capability of orbital remote sensing of photosynthetic communities out of the aquatic margins and into the drier soils which comprise most of this landscape. This interdisciplinary work is critical for measuring and monitoring terrestrial carbon stocks and predicting future ecosystem dynamics in this currently water-limited but increasingly dynamic Antarctic landscape, which is particularly climate-sensitive and difficult to access.	["POLYGON((161.70776367188 -77.519802097166,161.899475097661 -77.519802097166,162.091186523442 -77.519802097166,162.282897949223 -77.519802097166,162.474609375004 -77.519802097166,162.666320800785 -77.519802097166,162.858032226566 -77.519802097166,163.049743652347 -77.519802097166,163.241455078128 -77.519802097166,163.433166503909 -77.519802097166,163.62487792969 -77.519802097166,163.62487792969 -77.54867059480199,163.62487792969 -77.57753909243799,163.62487792969 -77.606407590074,163.62487792969 -77.63527608771,163.62487792969 -77.664144585346,163.62487792969 -77.69301308298199,163.62487792969 -77.72188158061799,163.62487792969 -77.750750078254,163.62487792969 -77.77961857589,163.62487792969 -77.808487073526,163.433166503909 -77.808487073526,163.241455078128 -77.808487073526,163.049743652347 -77.808487073526,162.858032226566 -77.808487073526,162.666320800785 -77.808487073526,162.474609375004 -77.808487073526,162.282897949223 -77.808487073526,162.091186523442 -77.808487073526,161.899475097661 -77.808487073526,161.70776367188 -77.808487073526,161.70776367188 -77.77961857589,161.70776367188 -77.750750078254,161.70776367188 -77.72188158061799,161.70776367188 -77.69301308298199,161.70776367188 -77.664144585346,161.70776367188 -77.63527608771,161.70776367188 -77.606407590074,161.70776367188 -77.57753909243799,161.70776367188 -77.54867059480199,161.70776367188 -77.519802097166))"]	["POINT(162.666320800785 -77.664144585346)"]	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

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