Twentieth-century channel change on the Dunajec River, southern Poland: Patterns, causes and controls

Do the coarsest bed fractions and stream power record contemporary trends in steep headwater channels?

“…Direct relation between the increasing stream power and the coarsening of bed sediments was documented in those Australian alluvial rivers, which do not flood over their banks at high flows (Brizga and Finlayson, 1990). Moreover, a gradual increase of unit stream power is also typical for degradation trends of gravel-bed rivers in the western Carpathians (Wyżga, 2001;Zawiejska and Wyżga, 2010).…”

Gravel-bed channel changes upstream of a reservoir: The case of the Dunajec River upstream of the Czorsztyn Reservoir, southern Poland

“…Granitic and quarzitic gravels constitute the maximum fraction. The high-energy flow regime of the Dunajec River is controlled by the high-mountain Tatra massif and the low retention potential of bedrock facilitating the generation of high peak discharges (Zawiejska and Wyżga, 2010). The average of the maximum annual discharge of the Dunajec River at the Kowaniec gauging station (directly above the study reach) equals 251.5 m 3 /s.…”

“…In the twentieth century the Dunajec River underwent significant narrowing and deepening, and its channel changed from multi-thread to single-thread, mainly as a result of intense river engineering works and gravel mining (Zawiejska and Krzemień, 2004;Zawiejska and Wyżga, 2010). These processes were particularly intense in the 1970s and 1980s.…”

Development of sediment slug upstream from the Czorsztyn Reservoir (southern Poland) and its interaction with river morphology

“…Wyżga et al (2012) indicated that this morphology resulted from the absence of engineering work and that high agricultural and pastoral pressure in the largely deforested catchment, which facilitated high sediment flux during large floods, promoted rapid reworking of the active channel zone and prevented vegetation expansion on the channel bars and on the floodplain. From the mid-twentieth century, the Dunajec River underwent significant narrowing and deepening, and its channel changed from multithread to single-thread (Zawiejska and Wyżga, 2010). This was likely from the river engineering work conducted here from the 1960s to the 1990s (Krzemień, 1981;Zawiejska and Krzemień, 2004), gravel mining, particularly intense in the 1950s and the 1960s (Dudziak, 1965), as well as from the reduction of sediment supply from the catchment caused by environmental and land use changes (Kopacz and Twardy, 2006;Wyżga et al, 2012).…”