Podrobnosti záznamu

Název
    Mobility of Pb in Sphagnum-derived peat
Údaj o odpovědnosti
    Melanie A. Vile, R. Kelman Wieder, Martin Novák
Autor
    Novák, Martin, 1959-
    Vile, Melanie A.
    Wieder, R. Kelman
Jazyk
    anglicky
Zdrojový dokument - seriál
    Biogeochemistry
Svazek/č.
    Vol. 45, no. 1
Strany
    p. 35-52
Rok
    1999
Poznámky
    2 obr., 1 tab., 3 s.bibl.
    Zkr. název ser.: Biogeochemistry
Předmětová skupina
    atmosférická depozice
    biochemie
    datování Pb/Pb
    iontová výměna
    izotopy Pb
    mobilita
    olovo
    rašeliniště
    srážky dešťové
    studie experimentální
    znečištění
Geografické jméno
    USA-Minnesota
Klíčové slovo
    Mobility
    Pb
    Peat
    Sphagnum-derived
Abstrakt (anglicky)
   One important assumption in applying 210Pb-dating is that atmospherically deposited 210Pb is immobilized in the peat or sediment column. This assumption has been challenged widely, but has never been evaluated experimentally. We evaluated Pb mobility and the chemical forms in which Pb is stabilized in peat profiles by adding either soluble or particulate Pb to intact peat cores that were maintained under different water level regimes (permanently high, permanently low, fluctuating between high and low) and were subjected to simulated precipitation over a five month period. By analyzing the behavior of stable Pb we made inferences about the expect behavior of 210Pb. Results indicate that added soluble Pb2+ was retained in the peat through physiochemical binding to organic matter, and as such Pb2+ was largely immobile in peat even under conditions of a fluctuating water table. Added particulate Pb was largely (most likely by physical entrapment), but not completely, immobilized in peat.
   In none of the water table treatment was there evidence to support mobility of Pb by alternating formation and oxidation of sulfides, or by any other mechanism. The binding of Pb2+ with organic matter at the peat surface, and the absence of Pb mobility lend credence to 210Pb-dating of Sphagnum-dominated peat deposits, which are over 90% organic matter throughout, and have high cation exchange capacities
Přispěvatel
    Česká geologická služba
Kód přispěvatele
    ČGS (UNM)
Zdrojový formát
    U
Datum vložení
    28. 3. 2008
Datum importu
    8. 8. 2012