Abstract
ABSTRACTNieves penitentes are pinnacle-shaped ice structures found at high elevations in the dry Andes. Here we report, using molecular and microscopic approaches, the first description of snow algae communities inhabiting penitente ice at 5,277 m a.s.l., demonstrating a new habitat for snow algae in one of the most extreme environments on Earth. Red ice patches on penitentes contained a microbial community dominated by algae in the genera Chlamydomonas and Chloromonas, both of which were closely related to known snow algae from alpine and polar environments. In contrast, we obtained few snow algae sequences from clear ice, but we did find cyanobacteria sequences and evidence of aeolian-deposited organic matter. Tephra (“soil”) within and just downhill from the penitente field hosted more complex bacterial and eukaryotic communities that were significantly different from ice communities in terms of both alpha and beta diversity. In this environment penitentes provide both water and shelter from harsh winds, high UV radiation, and thermal fluctuations, creating an oasis in an otherwise extreme landscape. Intriguingly, recent planetary investigations have suggested the existence of penitente-like structures on other planetary bodies of our solar system. Therefore, penitentes and the harsh environment that surrounds them provide a new terrestrial analog for astrobiological studies of life beyond Earth.
Highlights
Nieves penitentes are surface ablation ice forms that are commonly found in the dry Andes at high elevations, and were first mentioned in the scientific literature by Darwin (1839)
The most abundant algal operational taxonomic unit (OTU) in red ice is a 100 percent match for the snow algae Chlamydomonas nivalis (Table 1), and its closest environmental matches were from a variety of globally distributed glacial environments, including Mt
Our study revealed for the first time that snow algal communities similar to those in many other snow or ice environments are present in the ice of nieves penitentes, at least in the penitente field at 5,277 m a.s.l. on Volcán Llullaillaco
Summary
Nieves penitentes are surface ablation ice forms that are commonly found in the dry Andes at high elevations (above 4,000 m a.s.l.; Matthes 1934; Lliboitry 1954), and were first mentioned in the scientific literature by Darwin (1839). The name “penitente” is a Spanish word (meaning “penitent one”) that comes from the resemblance of a field of penitentes to a procession of monks in white robes doing penance (Betterton 2001). They form when snowfields are subjected to the unique combination of high radiation, low humidity, and dry winds, causing differential ablation that leads to the formation of spire-like ice pinnacles that can range in size from a few centimeters to more than 5 m in height. Once they start to form, further growth in height can occur by the melting downward of the wells between the spires (Bergeron, Berger, and Betterton 2006)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
