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Kondratyev A.N.
Channel problems
in headwaters
The rivers are divided into flat, semimountain
and mountain (Makkaveev N.I., 1955) in accordance of
the complex hydraulic, hydrological and morphological factors. Also acceptably to subdivide the corresponding types of head water.
All section of hydrological network take
part in united erosion-accumulative process. Thermodynamic systems found out
from balance in accordance with
Le Chatelier principle tries to return the broken balance. A.A. Bogdanov (1921) has increased this regularity on the other
natural processes.
The ratio between transporting ability of the flow and
bedload alluvium in river (relative transporting
ability) has of great importance (Butakov et al,
1996). Inequality reveals on different system level are differing. In system
"river - catchment area" discrepancy
(dissymmetry) between transporting ability of the flow and arrival alluvium
brings cut river into ground or raise. For the last 100-110 years in north Predvolzhie and west Zakamie Tartarstan disappeared beside 900 small rivers and brook (Dedkov A.P. et al, 1995). On system level "flow -
riverbed" dissymmetry brings to the change of the channel types. At large
arrival alluvium to overloading the riverbed alluvium and formation of point
and said bar processes. At small arrival alluvium brings about meandering development
(Kondratyev A.N., 1999).
The small rivers more subject to influence
antropogenic factor. For instance,
river Steepe Zay in Tartarstan and river Samara (a tributary of the
Volga) on
some parts traversed of ten oil underwater pipeline. The
Pipes are found above level of the bottom. Created current brings the
significant change of natural condition of river channels.
In each head water types (mountain, semimountain and flat) there are different types sources: underground water, lake, glaciers, marsh. On
northwest of the
Russia exist
the special types of headwaters rivers, flowed from greater lake:
Neva, Svir, Volkhov.
At present appeared the new specific type a headwaters – man-caused.
The river Krasnenikaya,
running on south Saint-Petersburg outskirts is explored. The river in mouth has
an average discharge 2 m3/s. On mark of the
high-watermark and hydrometric post data for past periods is realized that
maximum water discharge 5% suplies are beside 4 m3/s.
The Autumn 2003 discharge has formed 2 m3/s. The field
examination of the whole river length (about 15 km) has shown that its headwaters does not exist. Uptown is found on its place.
The River have Ligovskii
canal water. This canal was created in XVIII age and was used for providing by
drinking water Saint-Petersburg. Lower part of the canal was destructioned out at period 1940-60. The Ligovskii riverbed was united with river Krasnenikaya. Nearly, the whole discharge presents itself
unset of perfected water to heat power station No 15. The Natural discharge
measured by autumn 2003 was 10 l/s. The Industrial discharge was 2 m3/s (99,9% by total). Nearly, the whole discharge presented itself
industrial unset of water. The river changed in greater gutter, riverbed width
is 3-20 m. The whole unrefined water is thrown in area of water of the Nevsky Guba of the
Finland
Gulf.
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