TY - JOUR
T1 - Stromatolitic digitate sinters form under wide-ranging physicochemical conditions with diverse hot spring microbial communities
AU - Sriaporn, Chanenath
AU - Campbell, Kathleen A.
AU - Millan, Maeva
AU - Ruff, Steven W.
AU - Van Kranendonk, Martin J.
AU - Handley, Kim M.
N1 - Funding Information:
Funding was provided by the University of Auckland Faculty Research Development Fund, and a Royal Society Te Apārangi Rutherford Discovery Fellowship awarded to KMH. MVK was supported by the Australian Research Council through grant DP180103204.
Funding Information:
Funding was provided by the University of Auckland Faculty Research Development Fund, and a Royal Society Te?Ap?rangi Rutherford Discovery Fellowship awarded to KMH.?MVK was supported by the Australian Research Council through grant DP180103204. The authors thank B. Drake, M. Rowe, M. Dobson, S. Camp, Y. Heled, D. P. Aparicio, A. Hamilton and the rest of the members of the Hot Spring Research Group at the University of Auckland (UoA) for facilitating and helping with the field work and geochemistry data collection. We also thank C. Hobbis (Research Centre for Surface and Materials Science), A. Turner (School of Biological Sciences) and L. Cotterall (School of Environment) at UoA for technical support. We are grateful to D. Waite, J. Boey and E. Gios from the School of Biological Sciences?at UoA for bioinformatics support. We acknowledge Timberlands Ltd (Rotorua) for Orange Spring site access, Mercury Energy (Rotorua) and the New Zealand Department of Conservation (DOC) for Parariki Stream and Lake Rotokawa site access, R. and B. McNaull for Te?Kopia site access, Hell's Gate Ltd for Tikitere site access, and DOC for Whangapaoa Spring site access. Finally, the authors wish to acknowledge the use of New Zealand eScience Infrastructure (NeSI) high performance computing facilities.
Publisher Copyright:
© 2020 John Wiley & Sons Ltd
PY - 2020/9/1
Y1 - 2020/9/1
N2 - Digitate siliceous hot spring deposits are a form of biomediated sinter that is relatively common in the Taupo Volcanic Zone (TVZ), New Zealand, and elsewhere on Earth. Such deposits have gained prominence recently because of their morphological similarity to opaline silica rocks of likely hot spring origin found by the Spirit rover on Mars and the consequent implications for potential biosignatures there. Here, we investigate the possible relationship between microbial community composition and morphological diversity among digitate structures from actively forming siliceous hot spring sinters depositing subaerially in shallow discharge channels and around pool rims at several physicochemically distinct geothermal fields in the TVZ. The TVZ digitate sinters range in morphologic subtype from knobby to spicular, and are shown to be microstromatolites that grow under varied pH ranges, temperatures, and water chemistries. Scanning electron microscopy and molecular analyses revealed that TVZ digitate sinters are intimately associated with a diverse array of bacterial, archaeal and eukaryotic micro-organisms, and for most digitate structures the diversity and quantity of prokaryotes was higher than that of eukaryotes. However, microbial community composition was not correlated with morphologic subtypes of digitate sinter, and observations provided limited evidence that pH (acidic versus alkali) affects morphology. Instead, results suggest hydrodynamics may be an important factor influencing variations in morphology, while water chemistry, pH, and temperature are strong drivers of microbial composition and diversity.
AB - Digitate siliceous hot spring deposits are a form of biomediated sinter that is relatively common in the Taupo Volcanic Zone (TVZ), New Zealand, and elsewhere on Earth. Such deposits have gained prominence recently because of their morphological similarity to opaline silica rocks of likely hot spring origin found by the Spirit rover on Mars and the consequent implications for potential biosignatures there. Here, we investigate the possible relationship between microbial community composition and morphological diversity among digitate structures from actively forming siliceous hot spring sinters depositing subaerially in shallow discharge channels and around pool rims at several physicochemically distinct geothermal fields in the TVZ. The TVZ digitate sinters range in morphologic subtype from knobby to spicular, and are shown to be microstromatolites that grow under varied pH ranges, temperatures, and water chemistries. Scanning electron microscopy and molecular analyses revealed that TVZ digitate sinters are intimately associated with a diverse array of bacterial, archaeal and eukaryotic micro-organisms, and for most digitate structures the diversity and quantity of prokaryotes was higher than that of eukaryotes. However, microbial community composition was not correlated with morphologic subtypes of digitate sinter, and observations provided limited evidence that pH (acidic versus alkali) affects morphology. Instead, results suggest hydrodynamics may be an important factor influencing variations in morphology, while water chemistry, pH, and temperature are strong drivers of microbial composition and diversity.
KW - biosignature
KW - digitate sinter
KW - hot springs
KW - microbial communities
KW - silicification
KW - stromatolite
UR - http://www.scopus.com/inward/record.url?scp=85084127860&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85084127860&partnerID=8YFLogxK
U2 - 10.1111/gbi.12395
DO - 10.1111/gbi.12395
M3 - Article
C2 - 32336004
AN - SCOPUS:85084127860
SN - 1472-4677
VL - 18
SP - 619
EP - 640
JO - Geobiology
JF - Geobiology
IS - 5
ER -