Jökull - 01.01.2009, Blaðsíða 20

A. A. Beylich
Figure 1. Location of the three study areas in Iceland, Swedish and Finnish Lapland. – Staðsetning rannsókn-
arsvæðanna á Íslandi og í Lapplandi.
oceanic environment. Subsequently, research in vari-
ous cold environments in different parts of the world
has documented that chemical processes and denuda-
tion are significant in cold environments (e. g. Thorn,
1975; Thorn et al., 2001; Dixon et al., 1984; 1995;
2008; Caine, 1995; Gislason et al., 1996; Darmody et
al., 2000; 2001; Campbell et al., 2001; 2002; Beylich,
2005; 2008; Beylich et al., 2005b; 2006b; Louvat et
al., 2008).
Fluvial sediment transport in cold environments is
generally to a high extent confined to floods generated
by snowmelt, rainfall, or a combination of both (e. g.
Beylich et al., 2006a). The direct quantitative compar-
ison of fluvial solute fluxes, sedimentary fluxes and
sediment budgets as well as snowmelt- and rainfall
generated runoff peaks in catchments of similar size
(ca. 10–30 km2) in cold environments will provide in-
sight into their internal differentiation (Barsch, 1984;
1986; Beylich, 2000; 2008; Beylich and Kneisel,
2009).
In this paper I present data on the magnitude and
the relative importance of chemical and mechanical
fluvial denudation in three different cold environment
catchments in Eastern Iceland, northernmost Finnish
Lapland and northernmost Swedish Lapland (Fig-
ure 1). The results are based on field investigations
and monitoring programmeswhich have been running
over six years in Hrafndalur (Iceland) and Kidisjoki
(Finland) (2002–2007) and over eight years in Latn-
javagge (Sweden) (2000–2007) (Beylich, 2002; 2008;
Beylich et al., 2005b; 2006b; 2008).
STUDY AREAS
The Hrafndalur catchment (65◦28’N, 13◦42’W; 7
km2; 6–731 m a. s. l.) is situated in the northern
part of Eastern Iceland (Figures 1 and 2) in a re-
gion of sub-Arctic oceanic climate, with a high fre-
quency of high wind speeds, a mean annual precipi-
tation of 1719 mm yr−1 and a mean annual air tem-
perature of 3.6◦C. Runoff may occur any time of the
year with the highest discharges during spring snow
melt (April - June), wintry thaw events and during ex-
treme rainfall events which are most frequent in fall
(September-November) (Beylich, 2003). During dry
spells in summer and winter frosts the entire valley
can be without surface runoff. The steep and glacially
20 JÖKULL No. 59