『Abstract
Inputs of As to a small catchment due to chemical weathering
of bedrock, mechanical weathering of bedrock, and atmospheric
precipitation were 71.53, 23.98 and 0.02 g ha-1 year-1,
respectively. The output fluxes of As due to mechanical erosion
of soil, biological uptake, stream discharge, and groundwater
flow were 6.32, 4.77, 0.37 and 0.02 g ha-1 year-1,
respectively. The results indicate that arsenic accumulates in
soil and regolith with a very high rate. This is attributed to
the selective weathering and erosion with respect to arsenic and
fixation of arsenic in the secondary solids produced by weathering.
The output fluxes of As in stream and groundwater in Vydrica catchment
in Slovak Republic (0.39 g ha-1 year-1)
based on muscovite-biotite granites and granodiorites were much
lower compared to catchments in a gold district in the Czech Republic.
These results may be ascribed to the low levels of arsenic pollution
measured in Vydrica catchment. The arsenic fluxes were estimated
by calculation of mechanical and chemical weathering rates of
the bedrocks in Vydrica catchment from mass balance data on sodium
and silica. The justification of the steady state of Na and Si
is that neither of the elements is appreciably accumulated in
plants and in exchangeable pool of ions in soil.
Keywords: Mechanical erosion; Weathering rates; Arsenic; Catchment;
Slovak Republic』
Introduction
Major characteristics of the studied catchment
Theory
Materials and methods
Input and output fluxes of elements
Analytical methods
Results
Discussion
Conclusions
References