Prokaryotes in the WAIS Divide ice core reflect source and transport changes between Last Glacial Maximum and the early Holocene.

Autor: Santibáñez PA; Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, MT, USA.; Departamento Científico, Instituto Antártico Chileno (INACH), Punta Arenas, Chile., Maselli OJ; Desert Research Institute, Nevada System of Higher Education, Reno, NV, USA., Greenwood MC; Department of Mathematical Sciences, Montana State University, Bozeman, MT, USA., Grieman MM; Department of Earth System Science, University of California, Irvine, CA, USA., Saltzman ES; Department of Earth System Science, University of California, Irvine, CA, USA., McConnell JR; Desert Research Institute, Nevada System of Higher Education, Reno, NV, USA., Priscu JC; Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, MT, USA.
Jazyk: angličtina
Zdroj: Global change biology [Glob Chang Biol] 2018 May; Vol. 24 (5), pp. 2182-2197. Date of Electronic Publication: 2018 Feb 16.
DOI: 10.1111/gcb.14042
Abstrakt: We present the first long-term, highly resolved prokaryotic cell concentration record obtained from a polar ice core. This record, obtained from the West Antarctic Ice Sheet (WAIS) Divide (WD) ice core, spanned from the Last Glacial Maximum (LGM) to the early Holocene (EH) and showed distinct fluctuations in prokaryotic cell concentration coincident with major climatic states. The time series also revealed a ~1,500-year periodicity with greater amplitude during the Last Deglaciation (LDG). Higher prokaryotic cell concentration and lower variability occurred during the LGM and EH than during the LDG. A sevenfold decrease in prokaryotic cell concentration coincided with the LGM/LDG transition and the global 19 ka meltwater pulse. Statistical models revealed significant relationships between the prokaryotic cell record and tracers of both marine (sea-salt sodium [ssNa]) and burning emissions (black carbon [BC]). Collectively, these models, together with visual observations and methanosulfidic acid (MSA) measurements, indicated that the temporal variability in concentration of airborne prokaryotic cells reflected changes in marine/sea-ice regional environments of the WAIS. Our data revealed that variations in source and transport were the most likely processes producing the significant temporal variations in WD prokaryotic cell concentrations. This record provided strong evidence that airborne prokaryotic cell deposition differed during the LGM, LDG, and EH, and that these changes in cell densities could be explained by different environmental conditions during each of these climatic periods. Our observations provide the first ice-core time series evidence for a prokaryotic response to long-term climatic and environmental processes.
(© 2018 John Wiley & Sons Ltd.)
Databáze: MEDLINE
Externí odkaz: