Biologically induced formation of realgar deposits in soil

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388980%3A_____%2F17%3A00479104" target="_blank" >RIV/61388980:_____/17:00479104 - isvavai.cz</a>

Alternative codes found

RIV/00216208:11310/17:10369636

Result on the web

<a href="http://dx.doi.org/10.1016/j.gca.2017.09.023" target="_blank" >http://dx.doi.org/10.1016/j.gca.2017.09.023</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.gca.2017.09.023" target="_blank" >10.1016/j.gca.2017.09.023</a>

Result language

angličtina

Original language name

Biologically induced formation of realgar deposits in soil

Original language description

The formation of realgar (As4S4) has recently been identified as a prominent As sequestration pathway in the naturally As-enriched wetland soil at the Mokrsko geochemical anomaly (Czech Republic). Here we used bulk soil and pore water analyses, synchrotron X-ray absorption spectroscopy, S isotopes, and DNA extractions to determine the distribution and speciation of As as a function of soil depth and metabolic properties of microbial communities in wetland soil profiles. Total solid-phase analyses showed that As was strongly correlated with organic matter, caused by a considerable As accumulation (up to 21 g kg(-1)) in an organic-rich soil horizon artificially buried in 1980 at a depth of similar to 80 cm. Extended X-ray absorption fine structure spectroscopy revealed that As in the buried organic horizon was predominantly present as realgar occurring as nanocrystallites (50-100 nm) in millimeter-scale deposits associated with particulate organic matter. The realgar was depleted in the S-34 isotope by 9-12.5 parts per thousand relative to the aqueous sulfate supplied to the soil, implying its biologically induced formation. Analysis of the microbial communities by 16S rDNA sequencing showed that realgar deposits formed in strictly anaerobic organic-rich domains dominated by sulfate-reducing and fermenting metabolisms. In contrast, realgar deposits were not observed in similar domains with even small contributions of oxidative metabolisms. No association of realgar with specific microbial species was observed. Our investigation shows that strongly reducing microenvironments associated with buried organic matter are significant biogeochemical traps for As, with an estimated As accumulation rate of 61 g As m(-2) yr(-1). Nevertheless the production of biologically induced realgar in these microenvironments is too slow to lower As groundwater concentrations at our field site (similar to 6790 mg L-1).

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10402 - Inorganic and nuclear chemistry

Project

<a href="/en/project/GA16-09352S" target="_blank" >GA16-09352S: Towards a better understanding of environmental As mineralogy under reducing conditions:Formation of realgar and evaluation of its role in remediation</a><br>

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2017

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Geochimica et Cosmochimica Acta

ISSN

0016-7037

e-ISSN

—

Volume of the periodical

218

Issue of the periodical within the volume

DEC

Country of publishing house

GB - UNITED KINGDOM

Number of pages

20

Pages from-to

237-256

UT code for WoS article

000412998300013

EID of the result in the Scopus database

2-s2.0-85029933400