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Titel |
Ash leachates from some recent eruptions of Mount Etna (Italy) and Popocatépetl (Mexico) volcanoes and their impact on amphibian living freshwater organisms |
VerfasserIn |
M. D'Addabbo, R. Sulpizio, M. Guidi, G. Capitani, P. Mantecca, G. Zanchetta |
Medientyp |
Artikel
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Sprache |
Englisch
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ISSN |
1726-4170
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Digitales Dokument |
URL |
Erschienen |
In: Biogeosciences ; 12, no. 23 ; Nr. 12, no. 23 (2015-12-08), S.7087-7106 |
Datensatznummer |
250118202
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Publikation (Nr.) |
copernicus.org/bg-12-7087-2015.pdf |
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Zusammenfassung |
Leaching experiments were carried out on fresh ash samples from
Popocatépetl 2012, Etna 2011, and Etna 2012 eruptions, in order to investigate
the release of compounds in both double-deionized and lake (Lake Ohrid, FYR
of Macedonia) waters. The experiments were carried out using different grain
sizes and variable stirring times (from 30 min to 7 days). Results
were discussed in the light of changing pH and release of compounds for the
different leachates. In particular, Etna samples induced alkalinization, and
Popocatépetl samples induced acidification of the corresponding
leachates. The release of different elements does not show correlation with
the stirring time, with the measured maximum concentrations reached in the
first hours of washing. General inverse correlation with grain size was
observed only for Na+, K+, Cl−, Ca2+, Mg2+,
SO42−, and Mn2+, while the other analysed elements show a complex,
scattering relationship with grain size.
Geochemical modelling highlights leachates' saturation only for F and Si,
with Popocatépetl samples sometimes showing saturation in Fe.
The analysed leachates are classified as undrinkable for humans on the basis
of European laws, due to excess in F−, Mn2+, Fe, and
SO42− (the latter only for Popocatépetl samples).
Finally, the Etna 2012 and Popocatépetl leachates were used for toxicity
experiments on living biota (Xenopus laevis). They are mildly toxic, and no significant
differences exist between the toxic profiles of the two leachates. In
particular, no significant embryo mortality was observed; while even at high
dilutions, the leachates produced more than 20 % of malformed larvae. |
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