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Abstract Many challenges remain before we can fully understand the multifaceted role that natural organic matter (NOM) plays in soil and aquatic systems. These challenges remain despite the considerable progress that has been made in understanding NOM’s properties and reactivity using the latest analytical techniques. For nearly 4 decades, the International Humic Substances Society (IHSS, which is a non-profit scientific society) has distributed standard substances that adhere to strict isolation protocols and reference materials that are collected in bulk and originate from clearly defined sites. These NOM standard and reference samples offer relatively uniform materials for designing experiments and developing new analytical methods. The protocols for isolating NOM, and humic and fulvic acid fractions of NOM utilize well-established preparative scale column chromatography and reverse osmosis methods. These standard and reference NOM samples are used by the international scientific community to study NOM across a range of disciplines from engineered to natural systems, thereby seeding the transfer of knowledge across research fields. Recently, powerful new analytical techniques used to characterize NOM have revealed complexities in its composition that transcend the “microbial” vs. “terrestrial” precursor paradigm. To continue to advance NOM research in the Anthropocene epoch, a workshop was convened to identify potential new sites for NOM samples that would encompass a range of sources and precursor materials and would be relevant for studying NOM’s role in mediating environmental and biogeochemical processes. We anticipate that expanding the portfolio of IHSS reference and standard NOM samples available to the research community will enable this diverse group of scientists and engineers to better understand the role that NOM plays globally under the influence of anthropogenic mediated changes.
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Concentrations of iron bound to humic-like substances and total iron-binding capacity of humic-like substances from discrete samples collected on the GP17-ANT RVIB Palmer cruise NBP24-01 in the Amundsen Sea from Nov 2023 to Jan 2024
This dataset includes the concentrations of iron (Fe) bound to humic-like substances and total iron-binding capacity of humic-like substances from discrete depth profile and towfish samples collected on the GP17-ANT cruise NBP24-01 on the R/V IB Nathaniel B. Palmer in the Amundsen Sea from 29 November 2023 to 28 January 2024. This project investigates the impact of Fe-binding humic-like substances on Fe biogeochemistry in the Amundsen Sea. The project used a combination of depth profile and surface towfish samples to characterize the contributions of humic-like substances to Fe biogeochemistry across gradients in primary production, water masses, and bathymetric features in the Amundsen Sea. Understanding the distributions of Fe-binding humic-like substances provides insight into the impact of compositional changes of the Fe-binding ligand pool on Fe biogeochemistry and may help elucidate specific sources of these ligands.
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- PAR ID:
- 10620825
- Publisher / Repository:
- Biological and Chemical Oceanography Data Management Office (BCO-DMO)
- Date Published:
- Subject(s) / Keyword(s):
- humic substances iron biogeochemistry Amundsen Sea
- Format(s):
- Medium: X
- Location:
- Amundsen Sea Sector of the Antarctic Continental Margin
- Right(s):
- Creative Commons Attribution 4.0 International
- Institution:
- Oregon State University
- Sponsoring Org:
- National Science Foundation
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