Wetlands in River Valleys as an Effect of Fluvial Processes and Anthropopression - Wetlands and Water Framework Directive: Protection, Management and Climate Change - page 77

Fig. 5.10 The Czarny Dunajec River in the village of Wr ó bl ó wka

by: — South Ma ł opolska Protected Landscape Area, — Nature 2,000 bird directive

(Torfowiska Orawsko-Nowotarskie — PLB12,0007), — Nature 2,000 habitat direc-

tive (Torfowiska Orawsko-Nowotarskie — PLH120016).

5.4 Evidence of Wetlands in the Investigated Areas

Presently no wetlands can be found in the valley of the Vistula River near
Sandomierz ( Ł ajczak 2006b ), however numerous meander-shaped terrain forms
remain there (Fig. 5.11 ). Terraces of Vistula river are made of muds and cher-
nozems at a distance from 1 to 6 km from the river channel. This area used to be
covered by wetlands. Upstream of Sandomierz, on both terraces, the oxbow lakes
and the overgrown lakes exist. In Fig. 5.11 it is indicated that presently many of the
well visible bars are forming, which indicates high fl fluvial activity within the

channel of the Vistula River (Fig. 5.11 , left middle part of the picture). This

shows that within this reach the transported material can settle outside the current.
Forces connected to secondary current are responsible for creating channel or
alternate bars. They probably do not

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it the channel run after it was poorly designed
or there is no hydraulic balance between fluvial forces and critical forces charac-

terizing movement of bed material. This trend should exist in regulated rivers.
As long as Vistula tends to create meanders, the possibility of refreshing wetlands is
real. At present the process of restoring wetlands can be started from the network of
channels refreshing the existing oxbow lakes.
At present, the Nida River is an example where natural and regulated channels
can be found in the nearby area (Fig. 5.12 ). Currently there are two main old channels
in the valley (Fig. 5.6 ). One is the Old Nida, and the other is the Umianowicka Stream

fl