90
J. Dawidek et al.
the range of supply and the type and intensity of hydrochemical and hydrobiological
processes for this phase of the cycle. In the potamophase, there is a clear convergence
of physicochemical parameters of lake and river waters [24, 25], and the area of basin
supply is the catchment of the parent river (up to the profile at the place of water
supply to the lake). During high recharge of the valley with river waters, lakes may
disappear for some time. The lakes are then a hollow in the flooded floodplain terrace.
The floodplain lakes are most often found in the lower and middle sections of the river,
and the criterion determining the potential for their formation is the predominance
of lateral erosion processes over depth one in the river bed. Floodplain lakes do not
occur in the crenal and rhithral (spring and stream zones) but appear only in the
potamal (river zone). Detailed studies of erosion and cutting of meanders have been
carried out since the end of the nineteenth century [26], but initially, they were an
addition to comprehensive studies of valleys and rivers [26, 27]. Already then, the
need to divide lakes created by the activity of rivers was noticed. Due to a large
number of lakes and a large area of meandering lakes, the first typologies of river
valley lakes concerned these lakes.
According to [28], for a lake to be classified as a floodplain lake, it must:
(a) be located on a floodplain and shows some apparent relationship to the major
stream,
(b) be located within a distance of fifteen stream widths of the major stream,
(c) contain water,
(d) include at least one segment with a crescent-shaped channel (called the
“fundamental component”),
(e) have a size of the same general magnitude as the major stream, and
(f) be independent of other topographic influences, which means that each oxbow
lake must be free-standing.
Division of lakes by morphometry
The simplest floodplain lakes typologies were based on shoreline shape and development. Three types of lakes were distinguished in terms of oxbow lakes morphometry
[29].
– simple oxbow lakes are reservoirs with a compact, curved and not dismembered
basin with at least one arm through which river water is supplied (Fig. 6.2a),
– compound oxbow lakes with a dismembered basin, many channels and a
developed shoreline (Fig. 6.2b),
– complex oxbow lakes with a complex basin shape, which was created by
connecting several floodplain lakes into one body of water (Fig. 6.2c).
Another concept of typological division of meandering lakes by [28] also includes
three lake categories:
– open oxbow lakes (Fig. 6.3a)
– normal oxbow lakes (Fig. 6.3b)
– closed oxbow lakes (Fig. 6.3c).
J. Dawidek et al.
the range of supply and the type and intensity of hydrochemical and hydrobiological
processes for this phase of the cycle. In the potamophase, there is a clear convergence
of physicochemical parameters of lake and river waters [24, 25], and the area of basin
supply is the catchment of the parent river (up to the profile at the place of water
supply to the lake). During high recharge of the valley with river waters, lakes may
disappear for some time. The lakes are then a hollow in the flooded floodplain terrace.
The floodplain lakes are most often found in the lower and middle sections of the river,
and the criterion determining the potential for their formation is the predominance
of lateral erosion processes over depth one in the river bed. Floodplain lakes do not
occur in the crenal and rhithral (spring and stream zones) but appear only in the
potamal (river zone). Detailed studies of erosion and cutting of meanders have been
carried out since the end of the nineteenth century [26], but initially, they were an
addition to comprehensive studies of valleys and rivers [26, 27]. Already then, the
need to divide lakes created by the activity of rivers was noticed. Due to a large
number of lakes and a large area of meandering lakes, the first typologies of river
valley lakes concerned these lakes.
According to [28], for a lake to be classified as a floodplain lake, it must:
(a) be located on a floodplain and shows some apparent relationship to the major
stream,
(b) be located within a distance of fifteen stream widths of the major stream,
(c) contain water,
(d) include at least one segment with a crescent-shaped channel (called the
“fundamental component”),
(e) have a size of the same general magnitude as the major stream, and
(f) be independent of other topographic influences, which means that each oxbow
lake must be free-standing.
Division of lakes by morphometry
The simplest floodplain lakes typologies were based on shoreline shape and development. Three types of lakes were distinguished in terms of oxbow lakes morphometry
[29].
– simple oxbow lakes are reservoirs with a compact, curved and not dismembered
basin with at least one arm through which river water is supplied (Fig. 6.2a),
– compound oxbow lakes with a dismembered basin, many channels and a
developed shoreline (Fig. 6.2b),
– complex oxbow lakes with a complex basin shape, which was created by
connecting several floodplain lakes into one body of water (Fig. 6.2c).
Another concept of typological division of meandering lakes by [28] also includes
three lake categories:
– open oxbow lakes (Fig. 6.3a)
– normal oxbow lakes (Fig. 6.3b)
– closed oxbow lakes (Fig. 6.3c).