Mercury exports from a High-Arctic river basin in Northeast Greenland (74°N) largely controlled by glacial lake outburst floods
Research output: Contribution to journal › Journal article › Research › peer-review
Standard
Mercury exports from a High-Arctic river basin in Northeast Greenland (74°N) largely controlled by glacial lake outburst floods. / Sondergaard, Jens; Tamstorf, Mikkel; Elberling, Bo; Larsen, Martin M.; Mylius, Maria Rask; Lund, Magnus; Abermann, Jakob; Riget, Frank.
In: Science of the Total Environment, Vol. 514, 2015, p. 83-91.Research output: Contribution to journal › Journal article › Research › peer-review
Harvard
APA
Vancouver
Author
Bibtex
}
RIS
TY - JOUR
T1 - Mercury exports from a High-Arctic river basin in Northeast Greenland (74°N) largely controlled by glacial lake outburst floods
AU - Sondergaard, Jens
AU - Tamstorf, Mikkel
AU - Elberling, Bo
AU - Larsen, Martin M.
AU - Mylius, Maria Rask
AU - Lund, Magnus
AU - Abermann, Jakob
AU - Riget, Frank
N1 - CENPERM[2015]
PY - 2015
Y1 - 2015
N2 - Riverine mercury (Hg) export dynamics from the Zackenberg River Basin (ZRB) in Northeast Greenland were studied for the period 2009-2013. Dissolved and sediment-bound Hg was measured regularly in the Zackenberg River throughout the periods with running water (June-October) and coupled to water discharge measurements. Also, a few samples of snow, soil, and permafrost were analysed for Hg. Mean concentrations of dissolved and sediment-bound Hg in the river water (+/- SD) were 039 +/- 0.13 and 5.5 +/- 1.4 ng L-1, respectively, and mean concentrations of Hg in the river sediment were 0.033 +/- 0.025 mg kg(-1). Temporal variations in river Hg were mainly associated with snowmelt, sudden erosion events, and outburst floods from a glacier-dammed lake in the upper part of the ZRB. Annual Hg exports from the 514 km(2) ZRB varied from 0.71 to >1.57 kg and the majority (86-96 was associated with sediment-bound Hg. Hg yields from the ZRB varied from 1.4-3.1 g Hg km(-2) yr(-1) and were among the highest yields reported from Arctic river basins. River exports of Hg from ZRB were found to be largely controlled by the frequency, magnitude and timing of the glacial lake outburst floods, which occurred in four of the five years in July-August. Floods accounted for 5 to >10% of the annual water discharge, and up to >31% of the annual Hg export. Also, the winter snowfall and the summer temperatures were found to be important indirect controls on the annual Hg export. The occurrence and timing of glacial lake outburst floods in the ZRB in late summer at the time of maximum soil thaw depth, the location of the glacier in the upper ZRB, and increased thawing of the permafrost in Zackenberg in recent years leading to destabilisation of river banks are considered central factors explaining the high fraction of flood-controlled Hg export in this area. (C) 2015 Elsevier B.V. All rights reserved.
AB - Riverine mercury (Hg) export dynamics from the Zackenberg River Basin (ZRB) in Northeast Greenland were studied for the period 2009-2013. Dissolved and sediment-bound Hg was measured regularly in the Zackenberg River throughout the periods with running water (June-October) and coupled to water discharge measurements. Also, a few samples of snow, soil, and permafrost were analysed for Hg. Mean concentrations of dissolved and sediment-bound Hg in the river water (+/- SD) were 039 +/- 0.13 and 5.5 +/- 1.4 ng L-1, respectively, and mean concentrations of Hg in the river sediment were 0.033 +/- 0.025 mg kg(-1). Temporal variations in river Hg were mainly associated with snowmelt, sudden erosion events, and outburst floods from a glacier-dammed lake in the upper part of the ZRB. Annual Hg exports from the 514 km(2) ZRB varied from 0.71 to >1.57 kg and the majority (86-96 was associated with sediment-bound Hg. Hg yields from the ZRB varied from 1.4-3.1 g Hg km(-2) yr(-1) and were among the highest yields reported from Arctic river basins. River exports of Hg from ZRB were found to be largely controlled by the frequency, magnitude and timing of the glacial lake outburst floods, which occurred in four of the five years in July-August. Floods accounted for 5 to >10% of the annual water discharge, and up to >31% of the annual Hg export. Also, the winter snowfall and the summer temperatures were found to be important indirect controls on the annual Hg export. The occurrence and timing of glacial lake outburst floods in the ZRB in late summer at the time of maximum soil thaw depth, the location of the glacier in the upper ZRB, and increased thawing of the permafrost in Zackenberg in recent years leading to destabilisation of river banks are considered central factors explaining the high fraction of flood-controlled Hg export in this area. (C) 2015 Elsevier B.V. All rights reserved.
KW - Hg
KW - River export
KW - Arctic
KW - Snow
KW - Soil
KW - Permafrost
U2 - 10.1016/j.scitotenv.2015.01.097
DO - 10.1016/j.scitotenv.2015.01.097
M3 - Journal article
C2 - 25666278
VL - 514
SP - 83
EP - 91
JO - Science of the Total Environment
JF - Science of the Total Environment
SN - 0048-9697
ER -
ID: 140716665