| NSF Org: |
OPP Office of Polar Programs (OPP) |
| Recipient: |
|
| Initial Amendment Date: | June 7, 2017 |
| Latest Amendment Date: | February 23, 2023 |
| Award Number: | 1643534 |
| Award Instrument: | Standard Grant |
| Program Manager: |
William Ambrose
wambrose@nsf.gov (703)292-8048 OPP Office of Polar Programs (OPP) GEO Directorate for Geosciences |
| Start Date: | June 15, 2017 |
| End Date: | September 30, 2023 (Estimated) |
| Total Intended Award Amount: | $356,500.00 |
| Total Awarded Amount to Date: | $467,500.00 |
| Funds Obligated to Date: |
FY 2021 = $111,000.00 |
| History of Investigator: |
|
| Recipient Sponsored Research Office: |
2200 W MAIN ST DURHAM NC US 27705-4640 (919)684-3030 |
| Sponsor Congressional District: |
|
| Primary Place of Performance: |
NC US 27705-4010 |
| Primary Place of
Performance Congressional District: |
|
| Unique Entity Identifier (UEI): |
|
| Parent UEI: |
|
| NSF Program(s): |
Chemical Oceanography, ANT Organisms & Ecosystems |
| Primary Program Source: |
0100XXXXDB NSF RESEARCH & RELATED ACTIVIT |
| Program Reference Code(s): |
|
| Program Element Code(s): |
|
| Award Agency Code: | 4900 |
| Fund Agency Code: | 4900 |
| Assistance Listing Number(s): | 47.078 |
ABSTRACT
This project seeks to make detailed measurements of the oxygen content of the surface ocean along the Western Antarctic Peninsula. Detailed maps of changes in net oxygen content will be combined with measurements of the surface water chemistry and phytoplankton distributions. The project will determine the extent to which on-shore or offshore phytoplankton blooms along the peninsula are likely to lead to different amounts of carbon being exported to the deeper ocean. The project team members will participate in the development of new learning tools at the Museum of Life and Science. They will also teach secondary school students about aquatic biogeochemistry and climate, drawing directly from the active science supported by this grant.
The project will analyze oxygen in relation to argon that will allow determination of the physical and biological contributions to surface ocean oxygen dynamics. These assessments will be combined with spatial and temporal distributions of nutrients (iron and macronutrients) and irradiances. This will allow the investigators to unravel the complex interplay between ice dynamics, iron and physical mixing dynamics as they relate to Net Community Production (NCP) in the region. NCP measurements will be normalized to Particulate Organic Carbon (POC) and be used to help identify area of "High Biomass and Low NCP" and those with "Low Biomass and High NCP" as a function of microbial plankton community composition. The team will use machine learning methods- including decision tree assemblages and genetic programming- to identify plankton groups key to facilitating biological carbon fluxes. Decomposing the oxygen signal along the West Antarctic Peninsula will also help elucidate biotic and abiotic drivers of the O2 saturation to further contextualize the growing inventory of oxygen measurements (e.g. by Argo floats) throughout the global oceans.
PUBLICATIONS PRODUCED AS A RESULT OF THIS RESEARCH
Note:
When clicking on a Digital Object Identifier (DOI) number, you will be taken to an external
site maintained by the publisher. Some full text articles may not yet be available without a
charge during the embargo (administrative interval).
Some links on this page may take you to non-federal websites. Their policies may differ from
this site.
PROJECT OUTCOMES REPORT
Disclaimer
This Project Outcomes Report for the General Public is displayed verbatim as submitted by the Principal Investigator (PI) for this award. Any opinions, findings, and conclusions or recommendations expressed in this Report are those of the PI and do not necessarily reflect the views of the National Science Foundation; NSF has not approved or endorsed its content.
The effects of climate change are often amplified in polar regions. As temperatures rise, the reduction in polar ice results in more heat being absorbed by the oceans, instead of reflected back into the atmosphere by ice cover. The effect of these changes on polar ecosystems is poorly understood.
The goal of this grant was to study the physical and biogeochemical processes that affect the productivity of organisms at the Western Antarctic Peninsula (WAP). As part of this grant, we researched interannual variability in bacterial community structure and diversity, marine nitrogen fixation and net community production, and we addressed the possible use of environmental DNA as a monitoring tool in remote environments. Shifts in microbial community structures are expected with changing environmental conditions, but what this resulting community might look like is unknown. Our results demonstrated that WAP microbial community structure, carbon fluxes, and community interactions are influenced by sea ice conditions, and that biodiversity is negatively correlated to temperature.
Marine life depends on the availability on nutrients. For example, nitrogen can be a limiting factor in many environments. Biological nitrogen fixation is one of the main sources of nitrogen. We measured nitrogen fixation over a 3-month period from January to March 2019 with two independent methods. We found low and sporadic rates of nitrogen fixation at the WAP LTER, and found putative evidence of nitrogen fixation in Antarctic sediments, calling for future research into polar sedimentary nitrogen fixation.
Through the support of this grant, we have published 4 papers in journals such as Nature Communications (Lin et al. 2021), Limnology and Oceanography (Brown et al. 2021), Journal of Geophysical Research (Li et al. 2021), and Applied and Environmental Microbiology (Lin et al. 2019), and more papers are still in progress.
This grant supported the improvements of methods that will be used in future studies around the world. Gaining a deeper understanding of the mechanisms at play at the Western Antarctic Peninsula not only improves our knowledge of that specific region but also holds relevance for various scientific disciplines and ecological areas.
This grant supported the training of 2 postdoctoral and 5 doctoral students at Duke University, and outreach programs aimed at local (at Duke and at elementary and middle schools in the local community) and broader communities.
Brown et al. 2021: https://doi.org/10.1002/lno.11765
Li et al. 2021: https://doi.org/10.1029/2021JC017537
Lin et al. 2019: https://doi.org/10.1128/AEM.02634-18
Lin et al. 2021: https://doi.org/10.1038/s41467-021-25235-w
Last Modified: 01/20/2024
Modified by: Nicolas Cassar
Please report errors in award information by writing to: awardsearch@nsf.gov.
