Title: Ecosystem-bedrock interaction changes nutrient compartmentalization during early oxidative weathering

Abstract

Ecosystem-bedrock interactions power the biogeochemical cycles of Earth’s shallow crust, supporting life, stimulating substrate transformation, and spurring evolutionary innovation. While oxidative processes have dominated half of terrestrial history, the relative contribution of the biosphere and its chemical fingerprints on Earth’s developing regolith are still poorly constrained. Here, we report results from a two-year incipient weathering experiment. We found that the mass release and compartmentalization of major elements during weathering of granite, rhyolite, schist and basalt was rock-specific and regulated by ecosystem components. A tight interplay between physiological needs of different biota, mineral dissolution rates, and substrate nutrient availability resulted in intricate elemental distribution patterns. Biota accelerated CO₂ mineralization over abiotic controls as ecosystem complexity increased, and significantly modified the stoichiometry of mobilized elements. Microbial and fungal components inhibited element leaching (23.4% and 7%), while plants increased leaching and biomass retention by 63.4%. All biota left comparable biosignatures in the dissolved weathering products. Nevertheless, the magnitude and allocation of weathered fractions under abiotic and biotic treatments provide quantitative evidence for the role of major biosphere components in the evolution of upper continental crust, presenting critical information for large-scale biogeochemical models and for the search for stable in situ biosignatures beyond Earth.

Authors:

Zaharescu, Dragos G.  ^[1];

• Search DOE PAGES for author "Zaharescu, Dragos G."
• Search DOE PAGES for ORCID "0000-0002-6593-3739"

Burghelea, Carmen I. ^[2]; Dontsova, Katerina  ^[3];

• Search DOE PAGES for author "Dontsova, Katerina"
• Search DOE PAGES for ORCID "0000-0003-2177-8965"

Presler, Jennifer K. ^[2]; Hunt, Edward A. ^[2]; Domanik, Kenneth J. ^[4]; Amistadi, Mary K. ^[5]; Sandhaus, Shana ^[6]; Munoz, Elise N. ^[6]; Gaddis, Emily E. ^[7]; Galey, Miranda ^[8]; Vaquera-Ibarra, María O. ^[9]; Palacios-Menendez, Maria A. ^[10]; Castrejón-Martinez, Ricardo ^[11]; Roldán-Nicolau, Estefanía C. ^[11]; Li, Kexin ^[12]; Maier, Raina M. ^[13]; Reinhard, Christopher T. ^[14]; Chorover, Jon ^[3]

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+ Show Author Affiliations

1. Georgia Inst. of Technology, Atlanta, GA (United States). Department of Earth and Atmospheric Sciences; Univ. of California, Riverside, CA (United States). NASA Astrobiology Institute, Alternative Earths Team; Univ. of Arizona, Tucson, AZ (United States). Biosphere 2
2. Univ. of Arizona, Tucson, AZ (United States). Biosphere 2
3. Univ. of Arizona, Tucson, AZ (United States). Biosphere 2; Univ. of Arizona, Tucson, AZ (United States). Department of Environmental Science
4. Univ. of Arizona, Tucson, AZ (United States). Lunar and Planetary Laboratory
5. Univ. of Arizona, Tucson, AZ (United States). Arizona Laboratory for Emerging Contaminants
6. Univ. of Arizona, Tucson, AZ (United States). Biosphere 2; Univ. of Arizona, Tucson, AZ (United States). Honor’s College
7. Univ. of Arizona, Tucson, AZ (United States). Biosphere 2; Williams College, Williamstown, MA (United States)
8. Univ. of Arizona, Tucson, AZ (United States). Biosphere 2; Univ. of Minnesota, Minneapolis, MN (United States). Biology Department
9. Univ. of Arizona, Tucson, AZ (United States). Biosphere 2; University of the Americas Puebla (Mexico)
10. Univ. of Arizona, Tucson, AZ (United States). Biosphere 2; The University of Caribe, Cancun (Mexico)
11. Univ. of Arizona, Tucson, AZ (United States). Biosphere 2; National Autonomous University of Mexico, Mexico City (Mexico)
12. Univ. of Arizona, Tucson, AZ (United States). Biosphere 2; ; Univ. of Wisconsin, Madison, WI (United States). Department of Computer Sciences
13. The Univ. of Arizona, Department of Environmental Science, Tucson, AZ (United States); Univ. of Arizona, Tucson, AZ (United States). Department of Environmental Science
14. Georgia Inst. of Technology, Atlanta, GA (United States). Department of Earth and Atmospheric Sciences; Univ. of California, Riverside, CA (United States). NASA Astrobiology Institute, Alternative Earths Team

Publication Date:

Fri Oct 18 00:00:00 EDT 2019

Research Org.:

SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). Stanford Synchrotron Radiation Lightsource (SSRL)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES); National Science Foundation (NSF); United States-Mexico Commission for Educational and Cultural Exchange (COMEXUS); Thomas R. Brown Foundation

OSTI Identifier:

1624498

Grant/Contract Number:  

AC02-76SF00515; EAR-1023215; EAR-0724958; EAR-1331408

Resource Type:

Accepted Manuscript

Journal Name:

Scientific Reports

Additional Journal Information:

Journal Volume: 9; Journal Issue: 1; Journal ID: ISSN 2045-2322

Publisher:

Nature Publishing Group

Country of Publication:

United States

Language:

English

Subject:

54 ENVIRONMENTAL SCIENCES; Element cycles; Geochemistry