USAP-DC

Dissolved organic matter (DOM) comprises a significant pool of Earth's organic carbon that dwarfs the amount present in living aquatic organisms. The properties and reactivity of DOM are not well defined, and the evolution of autochthonous DOM from its precursor materials in freshwater has not been observed. Recent sampling of a supraglacial stream formed on the Cotton Glacier in the Transantarctic Mountains revealed DOM that more closely resembles an assemblage of recognizable precursor organic compounds, based upon its UV-VIS and fluorescence spectra. It is suggested that the DOM from this water evolved over time to resemble materials present in marine and many inland surface waters. The transient nature of the system i.e., it reforms seasonally, also prevents any accumulation of the refractory DOM present in most surface waters. Thus, the Cotton Glacier provides us with a unique environment to study the formation of DOM from precursor materials. An interdisciplinary team will study the biogeochemistry of this progenitor DOM and how microbes modify it. By focusing on the chemical composition of the DOM as it shifts from precursor material to the more humified fractions, the investigators will relate this transition to bioavailability, enzymatic activity, community composition and microbial growth efficiency. This project will support education at all levels, K-12, high school, undergraduate, graduate and post-doc and will increase participation by under-represented groups in science. Towards these goals, the investigators have established relationships with girls' schools and Native American programs. Additional outreach will be carried out in coordination with PolarTREC, PolarPalooza, and if possible, an Antarctic Artist and Writer.

Person	Role
Foreman, Christine	Investigator

Antarctic Organisms and Ecosystems

Award # 0838970

NSF-ANT08-38970_1

None in the Database

Repository	Title (link)	Format(s)	Status
USAP-DC	The Biogeochemical Evolution of Dissolved Organic Matter in a Fluvial System on the Cotton Glacier, Antarctica	None	exist

1. Smith, H. J., Tigges, M. , D'Andrilli, J. , Parker, A. , Bothner, B. and Foreman, C. M. (2018), Dynamic processing of DOM: Insight from exometabolomics, fluorescence spectroscopy, and mass spectrometry. Limnol. Oceanogr., 3: 225-235 (doi:10.1002/lol2.10082)
2. Smith, H., Dieser, M., McKnight, D., SanClements, M., & Foreman, C. (2018). Relationship between dissolved organic matter quality and microbial community composition across polar glacial environments. FEMS Microbiology Ecology, 94(7). (doi:10.1093/femsec/fiy090)
3. Smith, H. J., Foreman, C. M., Akiyama, T., Franklin, M. J., Devitt, N. P., & Ramaraj, T. (2016). Genome Sequence of Janthinobacterium sp. CG23_2, a Violacein-Producing Isolate from an Antarctic Supraglacial Stream. Genome Announcements, 4(1). (doi:10.1128/genomea.01468-15)
4. Dieser, M., Smith, H. J., Ramaraj, T., & Foreman, C. M. (2019). Janthinobacterium CG23_2: Comparative Genome Analysis Reveals Enhanced Environmental Sensing and Transcriptional Regulation for Adaptation to Life in an Antarctic Supraglacial Stream. Microorganisms, 7(10), 454. (doi:10.3390/microorganisms7100454)