δ53Cr values of catchment runoff exhibit seasonality regardless of bedrock Cr concentrations: Role of periodically changing chromium export fluxes

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00025798%3A_____%2F21%3A00000243" target="_blank" >RIV/00025798:_____/21:00000243 - isvavai.cz</a>

Alternative codes found

RIV/00216208:11320/21:10435734

Result on the web

<a href="https://onlinelibrary.wiley.com/doi/10.1002/hyp.14434" target="_blank" >https://onlinelibrary.wiley.com/doi/10.1002/hyp.14434</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1002/hyp.14434" target="_blank" >10.1002/hyp.14434</a>

Result language

angličtina

Original language name

δ53Cr values of catchment runoff exhibit seasonality regardless of bedrock Cr concentrations: Role of periodically changing chromium export fluxes

Original language description

One pre-requisite for the construction of a global chromium isotope mass balance is detailed understanding of Cr isotope systematics in the critical zone where redox-processes can modify the isotope signature of geogenic Cr input into the hydrosphere. A Cr isotope inventory of bedrock, soil and runoff was performed in a Central European headwater catchment underlain by amphibolite, situated in the vicinity of two previously studied catchments underlain by different bedrock types (serpentinite and leucogranite, respectively). Fresh bedrock in the amphibolite catchment NAZ contained ~300 mg kg-1 Cr, serpentinite at PLB contained ~800 mg kg-1 Cr, and leucogranite at LYS contained ~2 mg kg-1 Cr. Monthly hydrochemical monitoring at all three sites revealed higher Cr(VI) export fluxes in winter than in summer. NAZ was characterized by a distinct seasonality in the delta53Cr values, with minima during winter/spring snowmelts (-0.35 per mille) and maxima during dry summers (0.40per mille). Similar seasonality in delta53Cr values had been reported from PLB and LYS. Bedrock at all three sites had similar Cr isotope composition close to -0.10 per mille, a value indistinguishable from the delta53Cr value of bulk silicate Earth (BSE). Positive mean delta53Cr value of NAZ runoff indicated Cr-isotope fractionations during weathering of geogenic Cr(III), combined with adsorption of the resulting Cr(VI) on soil particles during pedogenesis. However, the massweighted mean delta53Cr of NAZ runoff was lower (-0.08 per mille), indistinguishable from the Cr isotope signature of bedrock. The same pattern of lower mass-weighted mean delta53Cr values ofrunoff, compared to arithmetic mean delta53Cr values of runoff, were observed also at PLB and LYS. We suggest that elevated Cr runoff fluxes in winter remove some of the residual isotopically light Cr that accumulated in the soil during summer. Seasonality in runoff delta53Cr values appears to be a relatively widespread phenomenon, de-coupled from Cr availability for chemical weathering

Czech name

—

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

10501 - Hydrology

Project

—

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2021

Confidentiality

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

Name of the periodical

Hydrological Processes

ISSN

0885-6087

e-ISSN

—

Volume of the periodical

35

Issue of the periodical within the volume

12 : e14434

Country of publishing house

GB - UNITED KINGDOM

Number of pages

12

Pages from-to

nestránkováno

UT code for WoS article

000737864100020

EID of the result in the Scopus database

2-s2.0-85121842652