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GSA Annual Meeting in Denver, Colorado, USA - 2016
Paper No. 31-8
Presentation Time: 3:40 PM
MICROBIAL MAT COMMUNITIES IN HAWAIIAN LAVA CAVES
SPILDE, Michael N.
, NORTHUP, Diana E.
, CAIMI, Nicole A.
, BOSTON, Penelope J.
, STONE, Frederick D.
, (1)Institute of Meteoritics, University of New Mexico, MSC03-2050, Albuquerque, NM 87131, (2)Biology Department,
University of New Mexico, MSC03-2020, Albuquerque, NM 87131, (3)NASA Astrobiology Institute, NASA Ames Research Center,
Moffett Field, CA 94035, (4)Natural Sciences Department, University of Hawaii at Hilo, Hilo, HI 96720, (5)Hawaii Speleological Survey,
Hilo, HI 96720, email@example.com
Microbial mats are a prominent feature in many Hawaiian lava caves, but little research has been done on these communities. Since
2008, we have sampled the microbial communities in16 lava caves on the Big Island of Hawai`i to conduct scanning electron
microscopy (SEM) analysis, cultivation, and DNA sequencing. These caves occurred in areas of Hawai`i that varied in rainfall from 47
to 400 cm per year and in flows that ranged in age from thousands of years to less than 100. Sampled communities included microbial
mats of various colors from white to tan, yellow, and orange; white mats floating on puddles in the floor; butterscotch-colored organic
ooze present in some caves on the walls or ceilings; and a blue-green lava stalactite from a single cave. We also sampled apparent
microbial mineral deposits to determine whether deposits contained substantial microorganisms. SEM studies revealed diverse
morphologies across the lava caves, with coccoid and filamentous shapes predominating in the microbial mats. The blue-green
stalactite exhibited unusual reticulated filaments that have been observed in a few other caves in New Mexico and Germany. Culture
media inoculated with microbial mat or mineral deposits on site in the lava caves revealed morphologies consistent with
Actinobacteria, and many cultures demonstrated the presence of fugitive dyes that were aqueously soluble. DNA analysis revealed
that the white wall microbial mats differed from the yellow, pink, and orange mats, which were similar to each other; Actinobacteria
dominated the latter deposits. Overall, the sample types (mat versus mineral versus surface soil) demonstrated significant phylogenic
differences, and little overlap between high and low precipitation regimes.
Session No. 31
Something for Everybody: The Many Faces of Karst Science in all its Multidisciplinary Glory
Abstract: MICROBIAL MAT COMMUNITIES IN HAWAIIAN LAVA CAVES (GSA... https://gsa.confex.com/gsa/2016AM/webprogram/Paper283965.html
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