Abstract

The marine nitrogen cycle is dominated by redox-controlled biogeochemical processes and, therefore, is likely to have been revolutionised in response to Earth-surface oxygenation. The details, timing, and trajectory of nitrogen cycle evolution, however, remain elusive. Here we couple nitrogen and carbon isotope records from multiple drillcores through the Rooihoogte–Timeball Hill Formations from across the Carletonville area of the Kaapvaal Craton where the Great Oxygenation Event (GOE) and its aftermath are recorded. Our data reveal that aerobic nitrogen cycling, featuring metabolisms involving nitrogen oxyanions, was well established prior to the GOE and that ammonium may have dominated the dissolved nitrogen inventory. Pronounced signals of diazotrophy imply a stepwise evolution, with a temporary intermediate stage where both ammonium and nitrate may have been scarce. We suggest that the emergence of the modern nitrogen cycle, with metabolic processes that approximate their contemporary balance, was retarded by low environmental oxygen availability.

Details

Title
Nitrogen fixation sustained productivity in the wake of the Palaeoproterozoic Great Oxygenation Event
Author
Luo, Genming 1 ; Junium, Christopher K 2 ; Izon, Gareth 3 ; Ono, Shuhei 3 ; Beukes, Nicolas J 4 ; Algeo, Thomas J 5 ; Cui, Ying 6 ; Xie, Shucheng 7 ; Summons, Roger E 3 

 State Key Laboratory of Biogeology and Environmental Geology, and School of Earth Science, China University of Geosciences, Wuhan, China; Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA 
 Department of Earth Sciences, Syracuse University, Syracuse, NY, USA 
 Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA 
 Department of Geology, DST-NRF Centre of Excellence for Integrated Mineral and Energy Resource Analysis, University of Johannesburg, Auckland Park, South Africa 
 State Key Laboratory of Biogeology and Environmental Geology, and School of Earth Science, China University of Geosciences, Wuhan, China; State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan, China; Department of Geology, University of Cincinnati, Cincinnati, OH, USA 
 Department of Earth Science, Dartmouth College, Hanover, NH, USA 
 State Key Laboratory of Biogeology and Environmental Geology, and School of Earth Science, China University of Geosciences, Wuhan, China 
Pages
1-9
Publication year
2018
Publication date
Mar 2018
Publisher
Nature Publishing Group
e-ISSN
20411723
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2011620857
Copyright
© 2018. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.