TITLE:
Heavy Metal Concentrations in Pores and Surface Waters during the Emptying of a Small Reservoir
AUTHORS:
Christian Opp, Jens Hahn, Nina Zitzer, Gabriela Laufenberg
KEYWORDS:
Heavy Metals, Reservoirs, Sediments, Surface Waters
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.3 No.10,
December
18,
2015
ABSTRACT: The impact of reservoir
emptying on the concentrations of dissolved heavy metals (As, Cd, Cr, Cu, Fe,
Mn, Ni, Pb and Zn) in pore and surface waters was studied in the Aar Reservoir,
a small reservoir in central Germany, during and after the emptying process.
This study was conducted to observe binding changes within pore waters as well
as the input of dissolved heavy metals in waters of the Aar Creek, what becomes
possible when the reservoirs water table is removed and lake sediments become
exposed. In pore waters, no clear shifting tendencies between dissolved and
sorbed heavy metal fractions could be found after the completed sediment
exposure. These relatively low dynamics in pore waters can be explained by the
fine texture of the lake sediments, which are characterized by a high water
holding capacity, what led to high remaining water contents and therefore
slowed down the redox changes. A few days after the completed emptying, a
general increase of dissolved heavy metal concentrations occurred in running
waters of the Aar Creek as a result of pore water drainage. Here, element
specific differences in mobilization and transportation abilities were found,
what can be reconstructed by the ratio of dissolved heavy metals in pore and
surface waters.