[{"awards": "1937546 Morgan-Kiss, Rachael; 1937595 Briggs, Brandon", "bounds_geometry": "POLYGON((162 -77.616667,162.1 -77.616667,162.2 -77.616667,162.3 -77.616667,162.4 -77.616667,162.5 -77.616667,162.6 -77.616667,162.7 -77.616667,162.8 -77.616667,162.9 -77.616667,163 -77.616667,163 -77.6283336,163 -77.6400002,163 -77.6516668,163 -77.6633334,163 -77.67500000000001,163 -77.68666660000001,163 -77.69833320000001,163 -77.7099998,163 -77.7216664,163 -77.733333,162.9 -77.733333,162.8 -77.733333,162.7 -77.733333,162.6 -77.733333,162.5 -77.733333,162.4 -77.733333,162.3 -77.733333,162.2 -77.733333,162.1 -77.733333,162 -77.733333,162 -77.7216664,162 -77.7099998,162 -77.69833320000001,162 -77.68666660000001,162 -77.67500000000001,162 -77.6633334,162 -77.6516668,162 -77.6400002,162 -77.6283336,162 -77.616667))", "dataset_titles": null, "datasets": null, "date_created": "Wed, 27 Jul 2022 00:00:00 GMT", "description": " Microbial communities are of more than just a scientific curiosity. Microbes represent the single largest source of evolutionary and biochemical diversity on the planet. They are the major agents for cycling carbon, nitrogen, phosphorus, and other elements through the ecosystem. Despite their importance in ecosystem function, microbes are still generally overlooked in food web models and nutrient cycles. Moreover, microbes do not live in isolation: their growth and metabolism are influenced by complex interactions with other microorganisms. This project will focus on the ecology, activity and roles of microbial communities in Antarctic Lake ecosystems. The team will characterize the genetic underpinnings of microbial interactions and the influence of environmental gradients (e.g. light, nutrients, oxygen, sulfur) and seasons (e.g. summer vs. winter) on microbial networks in Lake Fryxell and Lake Bonney in the Taylor Valley within the McMurdo Dry Valley region. Finally, the project furthers the NSF goals of training new generations of scientists by including undergraduate and graduate students, a postdoctoral researcher and a middle school teacher in both lab and field research activities. This partnership will involve a number of other outreach training activities, including visits to classrooms and community events, participation in social media platforms, and webinars. \u003cbr/\u003e\u003cbr/\u003ePart II: Technical description: Ecosystem function in the extreme Antarctic Dry Valleys ecosystem is dependent on complex biogeochemical interactions between physiochemical environmental factors (e.g. light, nutrients, oxygen, sulfur), time of year (e.g. summer vs. winter) and microbes. Microbial network complexity can vary in relation to specific abiotic factors, which has important implications on the fragility and resilience of ecosystems under threat of environmental change. This project will evaluate the influence of biogeochemical factors on microbial interactions and network complexity in two Antarctic ice-covered lakes. The study will be structured by three main objectives: 1) infer positive and negative interactions from rich spatial and temporal datasets and investigate the influence of biogeochemical gradients on microbial network complexity using a variety of molecular approaches; 2) directly observe interactions among microbial eukaryotes and their partners using flow cytometry, single-cell sorting and microscopy; and 3) develop metabolic models of specific interactions using metagenomics. Outcomes from amplicon sequencing, meta-omics, and single-cell genomic approaches will be integrated to map specific microbial network complexity and define the role of interactions and metabolic activity onto trends in limnological biogeochemistry in different seasons. These studies will be essential to determine the relationship between network complexity and future climate conditions. Undergraduate researchers will be recruited from both an REU program with a track record of attracting underrepresented minorities and two minority-serving institutions. To further increase polar literacy training and educational impacts, the field team will include a teacher as part of a collaboration with the successful NSF-funded PolarTREC program and participation in activities designed for public outreach.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 163.0, "geometry": "POINT(162.5 -77.67500000000001)", "instruments": null, "is_usap_dc": true, "keywords": "MICROALGAE; AQUATIC ECOSYSTEMS; Antarctica; LAKE/POND; BACTERIA/ARCHAEA; COMMUNITY DYNAMICS", "locations": "Antarctica", "north": -77.616667, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": null, "persons": "Morgan-Kiss, Rachael; Briggs, Brandon", "platforms": null, "repositories": null, "science_programs": null, "south": -77.733333, "title": "ANT LIA: Collaborative Research: Genetic Underpinnings of Microbial Interactions in Chemically Stratified Antarctic Lakes", "uid": "p0010355", "west": 162.0}, {"awards": "1744885 Moline, Mark", "bounds_geometry": "POLYGON((-64.643 -64.703149,-64.5388975 -64.703149,-64.43479500000001 -64.703149,-64.3306925 -64.703149,-64.22659 -64.703149,-64.1224875 -64.703149,-64.018385 -64.703149,-63.9142825 -64.703149,-63.81018 -64.703149,-63.706077500000006 -64.703149,-63.601975 -64.703149,-63.601975 -64.7258003,-63.601975 -64.7484516,-63.601975 -64.77110289999999,-63.601975 -64.7937542,-63.601975 -64.8164055,-63.601975 -64.8390568,-63.601975 -64.86170809999999,-63.601975 -64.8843594,-63.601975 -64.9070107,-63.601975 -64.929662,-63.706077500000006 -64.929662,-63.81018 -64.929662,-63.9142825 -64.929662,-64.018385 -64.929662,-64.1224875 -64.929662,-64.22659 -64.929662,-64.3306925 -64.929662,-64.43479500000001 -64.929662,-64.5388975 -64.929662,-64.643 -64.929662,-64.643 -64.9070107,-64.643 -64.8843594,-64.643 -64.86170809999999,-64.643 -64.8390568,-64.643 -64.8164055,-64.643 -64.7937542,-64.643 -64.77110289999999,-64.643 -64.7484516,-64.643 -64.7258003,-64.643 -64.703149))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 18 Jul 2022 00:00:00 GMT", "description": "This research project will use specially designed autonomous underwater vehicles (AUVs) to investigate interactions between Adelie and Gentoo penguins (the predators) and their primary food source, Antarctic krill (prey). While it has long been known that penguins feed on krill, details about how they search for food and target individual prey items is less well understood. Krill aggregate in large swarms, and the size or the depth of these swarms may influence the feeding behavior of penguins. Similarly, penguin feeding behaviors may differ based on characteristics of the environment, krill swarms, and the presence of other prey and predator species. This project will use specialized smart AUVs to simultaneously collect high-resolution observations of penguins, their prey, and environmental conditions. Data will shed light on strategies used by penguins prove foraging success during the critical summer chick-rearing period. This will improve predictions of how penguin populations may respond to changing environmental conditions in the rapidly warming Western Antarctic Peninsula region. Greater understanding of how individual behaviors shape food web structure can also inform conservation and management efforts in other marine ecosystems. This project has a robust public education and outreach plan linked with the Birch and Monterey Bay Aquariums.\u003cbr/\u003e\u003cbr/\u003ePrevious studies have shown that sub-mesoscale variability (1-10 km) in Antarctic krill densities and structure impact the foraging behavior of air-breathing predators. However, there is little understanding of how krill aggregation characteristics are linked to abundance on fine spatial scales, how these patterns are influenced by the habitat, or how prey characteristics influences the foraging behavior of predators. These data gaps remain because it is extremely challenging to collect detailed data on predators and prey simultaneously at the scale of an individual krill patch and single foraging event. Building on previously successful efforts, this project will integrate echosounders into autonomous underwater vehicles (AUVs), so that oceanographic variables and multi-frequency acoustic scattering from both prey and penguins can be collected simultaneously. This will allow for quantification of the environment at the scale of individual foraging events made by penguins during the critical 50+ day chick-rearing period. Work will be centered near Palmer Station, where long-term studies have provided significant insight into predator and prey population trends. The new data to be collected by this project will test hypotheses about how penguin prey selection and foraging behaviors are influenced by physical and biological features of their ocean habitat at extremely fine scale. By addressing the dynamic relationship between individual penguins, their prey, and habitat at the scale of individual foraging events, this study will begin to reveal the important processes regulating resource availability and identify what makes this region a profitable foraging habitat and breeding location.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -63.601975, "geometry": "POINT(-64.1224875 -64.8164055)", "instruments": null, "is_usap_dc": true, "keywords": "COASTAL; COMMUNITY DYNAMICS; ECOSYSTEM FUNCTIONS; SPECIES/POPULATION INTERACTIONS; Palmer Station; MICROALGAE; PENGUINS; ANIMALS/INVERTEBRATES", "locations": "Palmer Station", "north": -64.703149, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Integrated System Science", "paleo_time": null, "persons": "Moline, Mark; Benoit-Bird, Kelly; Cimino, Megan", "platforms": null, "repositories": null, "science_programs": null, "south": -64.929662, "title": "Collaborative Research: Linking Predator Behavior and Resource Distributions: Penguin-directed Exploration of an Ecological Hotspot", "uid": "p0010347", "west": -64.643}, {"awards": "1643652 Hofmann, Eileen; 1643618 Arrigo, Kevin", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Antarctic biological model output; Antarctic dFe model dyes", "datasets": [{"dataset_uid": "200210", "doi": "10.26008/1912/bco-dmo.782848.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Antarctic dFe model dyes", "url": "https://www.bco-dmo.org/dataset/782848"}, {"dataset_uid": "200211", "doi": "10.26008/1912/bco-dmo.858663.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Antarctic biological model output", "url": "https://www.bco-dmo.org/dataset/858663"}], "date_created": "Thu, 29 Apr 2021 00:00:00 GMT", "description": "Coastal waters surrounding Antarctica represent some of the most biologically rich and most untouched ecosystems on Earth. In large part, this biological richness is concentrated within the numerous openings that riddle the expansive sea ice (these openings are known as polynyas) near the Antarctic continent. These polynyas represent regions of enhanced production known as hot-spots and support the highest animal densities in the Southern Ocean. Many of them are also located adjacent to floating extensions of the vast Antarctic Ice Sheet and receive a substantial amount of meltwater runoff each year during the summer. However, little is known about the specific processes that make these ecosystems so biologically productive. Of the 46 Antarctic coastal polynyas that are presently known, only a handful have been investigated in detail.\r\nThis project will develop ecosystem models for the Ross Sea polynya, Amundsen polynya, and Pine Island polynya; three of the most productive Antarctic coastal polynyas. The primary goal is to use these models to better understand the fundamental physical, chemical, and biological interacting processes and differences in these processes that make these systems so biologically productive yet different in some respects (e.g. size and productivity) during the present day settings. Modeling efforts will also be extended to potentially assess how these ecosystems may have functioned in the past and how they might change in the future under different physical and chemical and climatic settings.\r\nThe project will advance the education of underrepresented minorities through Stanford?s Summer Undergraduate Research in Geoscience and Engineering (SURGE) Program. SURGE will provide undergraduates the opportunity to gain mentored research experiences at Stanford University in engineering and the geosciences. Old Dominion University also will utilize an outreach programs for local public and private schools as well as an ongoing program supporting the Boy Scout Oceanography merit badge program to create outreach and education impacts.\r\n\r\nPolynyas (areas of open water surrounded by sea ice) are disproportionately productive regions of polar ecosystems, yet controls on their high rates of production are not well understood. This project will provide quantitative assessments of the physical and chemical processes that control phytoplankton abundance and productivity within polynyas, how these differ for different polynyas, and how polynyas may change in the future. Of particular interest are the interactions among processes within the polynyas and the summertime melting of nearby ice sheets, including the Thwaites and Pine Island glaciers.\r\nIn this proposed study, we will develop a set of comprehensive, high resolution coupled physical-biological models and implement these for three major, but diverse, Antarctic polynyas. These polynyas, the Ross Sea polynya, the Amundsen polynya, and Pine Island polynya, account for \u003e50% of the total Antarctic polynya production.\r\nThe research questions to be addressed are: 1) What environmental factors exert the greatest control of primary production in polynyas around Antarctica? 2) What are the controlling physics that leads to the heterogeneity of dissolved iron (dFe) supply to the euphotic zone in polynyas around the Antarctic continental shelf? What effect does this have on local rates of primary production? 3) What are the likely changes in the supply of dFe to the euphotic zone in the next several decades due to climate-induced changes in the physics (winds, sea-ice, ice shelf basal melt, cross-shelf exchange, stratification and vertical mixing) and how will this affect primary productivity around the continent?\r\nThe Ross Sea, Amundsen, and Pine Island polynyas are some of the best-sampled polynyas in Antarctica, facilitating model parameterization and validation. Furthermore, these polynyas differ widely in their size, location, sea ice dynamics, relationship to melting ice shelves, and distance from the continental shelf break, making them ideal case studies. For comparison, the western Antarctic Peninsula (wAP), a productive continental shelf where polynyas are a relatively minor contributor to biological production, will also be modeled. Investigating specific processes within different types Antarctic coastal waters will provide a better understand of how these important biological oases function and how they might change under different environmental conditions.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "trace metal; AMD; Polynas; PELAGIC; POLYNYAS; PHYTOPLANKTON; MODELS; USAP-DC; MICROALGAE; USA/NSF; TRACE ELEMENTS; ICE SHEETS; Antarctica; AMD/US", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "van Dijken, Gert; Arrigo, Kevin; Dinniman, Michael; Hofmann, Eileen", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repo": "BCO-DMO", "repositories": "BCO-DMO", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Elucidating Environmental Controls of Productivity in Polynas and the Western Antarctic Peninsula", "uid": "p0010175", "west": -180.0}]

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ANT LIA: Collaborative Research: Genetic Underpinnings of Microbial Interactions in Chemically Stratified Antarctic Lakes

1937546
1937595

2022-07-27

Morgan-Kiss, Rachael; Briggs, Brandon

No dataset link provided

Microbial communities are of more than just a scientific curiosity. Microbes represent the single largest source of evolutionary and biochemical diversity on the planet. They are the major agents for cycling carbon, nitrogen, phosphorus, and other elements through the ecosystem. Despite their importance in ecosystem function, microbes are still generally overlooked in food web models and nutrient cycles. Moreover, microbes do not live in isolation: their growth and metabolism are influenced by complex interactions with other microorganisms. This project will focus on the ecology, activity and roles of microbial communities in Antarctic Lake ecosystems. The team will characterize the genetic underpinnings of microbial interactions and the influence of environmental gradients (e.g. light, nutrients, oxygen, sulfur) and seasons (e.g. summer vs. winter) on microbial networks in Lake Fryxell and Lake Bonney in the Taylor Valley within the McMurdo Dry Valley region. Finally, the project furthers the NSF goals of training new generations of scientists by including undergraduate and graduate students, a postdoctoral researcher and a middle school teacher in both lab and field research activities. This partnership will involve a number of other outreach training activities, including visits to classrooms and community events, participation in social media platforms, and webinars. Part II: Technical description: Ecosystem function in the extreme Antarctic Dry Valleys ecosystem is dependent on complex biogeochemical interactions between physiochemical environmental factors (e.g. light, nutrients, oxygen, sulfur), time of year (e.g. summer vs. winter) and microbes. Microbial network complexity can vary in relation to specific abiotic factors, which has important implications on the fragility and resilience of ecosystems under threat of environmental change. This project will evaluate the influence of biogeochemical factors on microbial interactions and network complexity in two Antarctic ice-covered lakes. The study will be structured by three main objectives: 1) infer positive and negative interactions from rich spatial and temporal datasets and investigate the influence of biogeochemical gradients on microbial network complexity using a variety of molecular approaches; 2) directly observe interactions among microbial eukaryotes and their partners using flow cytometry, single-cell sorting and microscopy; and 3) develop metabolic models of specific interactions using metagenomics. Outcomes from amplicon sequencing, meta-omics, and single-cell genomic approaches will be integrated to map specific microbial network complexity and define the role of interactions and metabolic activity onto trends in limnological biogeochemistry in different seasons. These studies will be essential to determine the relationship between network complexity and future climate conditions. Undergraduate researchers will be recruited from both an REU program with a track record of attracting underrepresented minorities and two minority-serving institutions. To further increase polar literacy training and educational impacts, the field team will include a teacher as part of a collaboration with the successful NSF-funded PolarTREC program and participation in activities designed for public outreach. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

Collaborative Research: Linking Predator Behavior and Resource Distributions: Penguin-directed Exploration of an Ecological Hotspot

1744885

2022-07-18

Moline, Mark; Benoit-Bird, Kelly; Cimino, Megan

No dataset link provided

This research project will use specially designed autonomous underwater vehicles (AUVs) to investigate interactions between Adelie and Gentoo penguins (the predators) and their primary food source, Antarctic krill (prey). While it has long been known that penguins feed on krill, details about how they search for food and target individual prey items is less well understood. Krill aggregate in large swarms, and the size or the depth of these swarms may influence the feeding behavior of penguins. Similarly, penguin feeding behaviors may differ based on characteristics of the environment, krill swarms, and the presence of other prey and predator species. This project will use specialized smart AUVs to simultaneously collect high-resolution observations of penguins, their prey, and environmental conditions. Data will shed light on strategies used by penguins prove foraging success during the critical summer chick-rearing period. This will improve predictions of how penguin populations may respond to changing environmental conditions in the rapidly warming Western Antarctic Peninsula region. Greater understanding of how individual behaviors shape food web structure can also inform conservation and management efforts in other marine ecosystems. This project has a robust public education and outreach plan linked with the Birch and Monterey Bay Aquariums. Previous studies have shown that sub-mesoscale variability (1-10 km) in Antarctic krill densities and structure impact the foraging behavior of air-breathing predators. However, there is little understanding of how krill aggregation characteristics are linked to abundance on fine spatial scales, how these patterns are influenced by the habitat, or how prey characteristics influences the foraging behavior of predators. These data gaps remain because it is extremely challenging to collect detailed data on predators and prey simultaneously at the scale of an individual krill patch and single foraging event. Building on previously successful efforts, this project will integrate echosounders into autonomous underwater vehicles (AUVs), so that oceanographic variables and multi-frequency acoustic scattering from both prey and penguins can be collected simultaneously. This will allow for quantification of the environment at the scale of individual foraging events made by penguins during the critical 50+ day chick-rearing period. Work will be centered near Palmer Station, where long-term studies have provided significant insight into predator and prey population trends. The new data to be collected by this project will test hypotheses about how penguin prey selection and foraging behaviors are influenced by physical and biological features of their ocean habitat at extremely fine scale. By addressing the dynamic relationship between individual penguins, their prey, and habitat at the scale of individual foraging events, this study will begin to reveal the important processes regulating resource availability and identify what makes this region a profitable foraging habitat and breeding location. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

Collaborative Research: Elucidating Environmental Controls of Productivity in Polynas and the Western Antarctic Peninsula

1643652
1643618

2021-04-29

van Dijken, Gert; Arrigo, Kevin; Dinniman, Michael; Hofmann, Eileen

Antarctic dFe model dyes	BCO-DMO
Antarctic biological model output	BCO-DMO

Coastal waters surrounding Antarctica represent some of the most biologically rich and most untouched ecosystems on Earth. In large part, this biological richness is concentrated within the numerous openings that riddle the expansive sea ice (these openings are known as polynyas) near the Antarctic continent. These polynyas represent regions of enhanced production known as hot-spots and support the highest animal densities in the Southern Ocean. Many of them are also located adjacent to floating extensions of the vast Antarctic Ice Sheet and receive a substantial amount of meltwater runoff each year during the summer. However, little is known about the specific processes that make these ecosystems so biologically productive. Of the 46 Antarctic coastal polynyas that are presently known, only a handful have been investigated in detail. This project will develop ecosystem models for the Ross Sea polynya, Amundsen polynya, and Pine Island polynya; three of the most productive Antarctic coastal polynyas. The primary goal is to use these models to better understand the fundamental physical, chemical, and biological interacting processes and differences in these processes that make these systems so biologically productive yet different in some respects (e.g. size and productivity) during the present day settings. Modeling efforts will also be extended to potentially assess how these ecosystems may have functioned in the past and how they might change in the future under different physical and chemical and climatic settings. The project will advance the education of underrepresented minorities through Stanford?s Summer Undergraduate Research in Geoscience and Engineering (SURGE) Program. SURGE will provide undergraduates the opportunity to gain mentored research experiences at Stanford University in engineering and the geosciences. Old Dominion University also will utilize an outreach programs for local public and private schools as well as an ongoing program supporting the Boy Scout Oceanography merit badge program to create outreach and education impacts. Polynyas (areas of open water surrounded by sea ice) are disproportionately productive regions of polar ecosystems, yet controls on their high rates of production are not well understood. This project will provide quantitative assessments of the physical and chemical processes that control phytoplankton abundance and productivity within polynyas, how these differ for different polynyas, and how polynyas may change in the future. Of particular interest are the interactions among processes within the polynyas and the summertime melting of nearby ice sheets, including the Thwaites and Pine Island glaciers. In this proposed study, we will develop a set of comprehensive, high resolution coupled physical-biological models and implement these for three major, but diverse, Antarctic polynyas. These polynyas, the Ross Sea polynya, the Amundsen polynya, and Pine Island polynya, account for >50% of the total Antarctic polynya production. The research questions to be addressed are: 1) What environmental factors exert the greatest control of primary production in polynyas around Antarctica? 2) What are the controlling physics that leads to the heterogeneity of dissolved iron (dFe) supply to the euphotic zone in polynyas around the Antarctic continental shelf? What effect does this have on local rates of primary production? 3) What are the likely changes in the supply of dFe to the euphotic zone in the next several decades due to climate-induced changes in the physics (winds, sea-ice, ice shelf basal melt, cross-shelf exchange, stratification and vertical mixing) and how will this affect primary productivity around the continent? The Ross Sea, Amundsen, and Pine Island polynyas are some of the best-sampled polynyas in Antarctica, facilitating model parameterization and validation. Furthermore, these polynyas differ widely in their size, location, sea ice dynamics, relationship to melting ice shelves, and distance from the continental shelf break, making them ideal case studies. For comparison, the western Antarctic Peninsula (wAP), a productive continental shelf where polynyas are a relatively minor contributor to biological production, will also be modeled. Investigating specific processes within different types Antarctic coastal waters will provide a better understand of how these important biological oases function and how they might change under different environmental conditions.

USAP-DC