Rights statement: This is the author’s version of a work that was accepted for publication in Quaternary Science Reviews. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Quaternary Science Reviews, 127, 2015 DOI: 10.1016/j.quascirev.2015.05.016
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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
}
TY - JOUR
T1 - Sulphate concentration in cave dripwater and speleothems
T2 - long-term trends and overview of its significance as proxy for environmental processes and climate changes
AU - Borsato, Andrea
AU - Frisia, Silvia
AU - Wynn, Peter Michael
AU - Fairchild, Ian J.
AU - Miorandi, Renza
N1 - This is the author’s version of a work that was accepted for publication in Quaternary Science Reviews. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Quaternary Science Reviews, 127, 2015 DOI: 10.1016/j.quascirev.2015.05.016
PY - 2015/11/1
Y1 - 2015/11/1
N2 - Sulphate concentrations in speleothems identify major volcanic eruptions, provide useful information on soil and aquifer dynamics and, in similar fashion to the 14C bomb peak, its Anthropocene peak can be used to date recent cave formations. However, the transmission of S from the atmosphere to cave dripwater and its incorporation in speleothems is subjected to biogeochemical cycling and accurate studies of each cave site are needed in order to assess how the S atmospheric signal is modified and eventually encoded in speleothems. This study investigates the role of biogeochemical cycling and aquifer hydrology by utilising published and new dripwater and speleothem data from Grotta di Ernesto (ER) in northern Italy. Here we provide the first long-term record of sulphate concentration in cave dripwater based on over 20 years of measurements. Fast drip site st-ER1 is characterised by a continuous decrease in SO4 concentration from a high of 7.5 ± 0.8 mg/l in 1993–1994 to a low of 2.2 ± 0.2 mg/l in 2013–2014, and replicates with a delay of ∼15 years the decline in the atmospheric SO2 emissions. The S-series of slow flow ER78 site is further delayed by ∼4.5 years in relation to the S retention in the aquifer matrix. The dripwater data are used to extend the previously published S record (1810–1998 AD) of stalagmite ER78 and reconstruct the anthropogenic S-peak: this displays a delay of ∼20 years with respect to the atmospheric S emission peak due to biogeochemical cycling and aquifer storage. However, sulphur recycling above the cave did not operate with the same degree of efficiency through time, which resulted in a variable time delay between S deposition and incorporation into the stalagmite. In the pre-Anthropocene era, and in particular during the cold Little Ice Age, biogeochemical cycling was far less efficient than today, and the fast transmission of the atmospheric signal allowed capture of S released during major volcanic eruptions by stalagmites.
AB - Sulphate concentrations in speleothems identify major volcanic eruptions, provide useful information on soil and aquifer dynamics and, in similar fashion to the 14C bomb peak, its Anthropocene peak can be used to date recent cave formations. However, the transmission of S from the atmosphere to cave dripwater and its incorporation in speleothems is subjected to biogeochemical cycling and accurate studies of each cave site are needed in order to assess how the S atmospheric signal is modified and eventually encoded in speleothems. This study investigates the role of biogeochemical cycling and aquifer hydrology by utilising published and new dripwater and speleothem data from Grotta di Ernesto (ER) in northern Italy. Here we provide the first long-term record of sulphate concentration in cave dripwater based on over 20 years of measurements. Fast drip site st-ER1 is characterised by a continuous decrease in SO4 concentration from a high of 7.5 ± 0.8 mg/l in 1993–1994 to a low of 2.2 ± 0.2 mg/l in 2013–2014, and replicates with a delay of ∼15 years the decline in the atmospheric SO2 emissions. The S-series of slow flow ER78 site is further delayed by ∼4.5 years in relation to the S retention in the aquifer matrix. The dripwater data are used to extend the previously published S record (1810–1998 AD) of stalagmite ER78 and reconstruct the anthropogenic S-peak: this displays a delay of ∼20 years with respect to the atmospheric S emission peak due to biogeochemical cycling and aquifer storage. However, sulphur recycling above the cave did not operate with the same degree of efficiency through time, which resulted in a variable time delay between S deposition and incorporation into the stalagmite. In the pre-Anthropocene era, and in particular during the cold Little Ice Age, biogeochemical cycling was far less efficient than today, and the fast transmission of the atmospheric signal allowed capture of S released during major volcanic eruptions by stalagmites.
KW - Sulphur
KW - Speleothems
KW - Karst water
KW - Volcanic eruptions
KW - Anthropogenic sulphur peak
U2 - 10.1016/j.quascirev.2015.05.016
DO - 10.1016/j.quascirev.2015.05.016
M3 - Journal article
VL - 127
SP - 48
EP - 60
JO - Quaternary Science Reviews
JF - Quaternary Science Reviews
SN - 0277-3791
ER -