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1

Features of the Sediment Runoff Regime Downstream the Ile River

Duskayev Kassym, Myrzakhmetov Akhan, Zhanabayeva Zhanar, Klein Igor

Journal of Ecological Engineering

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2020

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Vol. 21, nr 2

117--125

EN

This paper is devoted to study on the sediment runoff of the Ile River downstream. The article analyses the Kapshagai reservoir impact on the regime and characteristics of the sediment runoff in the Ile River downstream before and after construction of the reservoir in 1970. Along with the calculation of characteristics of sediment runoff, an assessment of the amount of the suspended sediment, which is in the bowl of the reservoir, was shown. Furthermore, the impact reservoir on the granulometric composition of the suspended and bed sediment of Ile River was calculated.

2

The evaluation of hydrodynamic balance at the Wkra River estuary

Siwicki P., Urbański L., Hejduk L., Gładecki J.

Meteorology Hydrology and Water Management. Research and Operational Applications

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2016

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Vol. 4, iss. 2

29--34

EN

The river bed stability analysis at the Wkra estuary reach is presented in this paper. When a flood appears, channel and river bed erosion can reach a significant size. During such a situation, flow and water velocity exceed critical values for particular bed sediment grain sizes. This causes the breakage of bed armouring, and then bed mass motion begins. For the estimation of the sandy Wkra River bed the criteria of average velocity and bed armouring were applied with the use of ARMOUR software. The two Wkra River cross-sections at km 1+000 and km 3+200 distance were analysed. The calculation of the characteristics of bed sediment velocities was performed on the basis of, among other factors, probable river flow data, longitudinal slope, and grain size distribution of the bed. The results of the calculations were compared with average velocities in the analysed cross-sections. The results indicate the there is a threat to the stability of the Wkra River bed, especially during long-lasting high water stages. The prognosis of river bed stability loss performed by use of ARMOUR software shows that the bed armour breakage will take place in both considered cross-sections at relatively low water stages (about 40 cm), and mass motion of bed sediments in cross-section P-2 will occur at a flow of slightly lower than Q50% ,and in cross-section P-1 at flows greater then Q0,3%.

3

Badanie wpływu zmian współczynnika szorstkości na wielkość przepływu obliczeniowego

Słowik-Opoka E., Brożek M.

Landform Analysis

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2015

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Vol. 30

49--56

PL

W pracy podjęto próbę określenia relacji między szorstkością koryta rzeki podgórskiej, wyrażoną współczynnikiem szorstkości a wielkością przepływu obliczeniowego. Z uwagi na fakt, że dobór zawyżonych wartości współczynnika szorstkości (n) może prowadzić do błędnego określania wielkości przepływu oraz wymiarowania przekroi poprzecznych koryt rzek i potoków w ramach pracy wykonano obliczenia wielkości przepływu (Q) z uwzględnieniem wartości (n) obliczonego wg różnych formuł. Przeprowadzone zostały pomiary hydrometryczne oraz geodezyjne. Pobrane zostały próbki rumowiska dennego celem określenia średnic charakterystycznych rumowiska, które posłużyły do obliczeń współczynników: szorstkości (n) oraz oporu przepływu (f) na badanym odcinku rzeki. W oparciu o analizę wyników badań stwierdzono, że decydujący wpływ na wartość współczynnika szorstkości wywiera średnica ziaren. Z uwagi na złożoność zagadnienia, potwierdzenie hipotezy o istnieniu bezpośredniego związku pomiędzy współczynnikiem szorstkości a głębokością wody w korycie wymaga przeprowadzenia dodatkowych badań.

EN

The study attempts to describe the relationship between roughness of mountain river beds, expressed by the roughness coefficient and the water depth of the river. Due to the fact that the selection of inflated values of the coefficient (n) can lead to erroneous determination of the discharge and dimensioning of river cross sections, the discharge (Q) has been calculated using values of (n) which were derived using different formulas. Hydrometric measurements and surveying were performed, samples were also collected to determine dimensions of sediment particles, which were used to calculate the coefficients: roughness (n) and resistance to flow (f) on the tested section of the river. Based on the analysis of test results, it was found that the diameter of grains had the decisive influence on the value of roughness. Due to the complexity of the issue, the confirmation of the hypothesis of the existence of a direct relationship between the ratio of roughness coefficient and the water depth in the river channel requires more research.

4

Transport of the river load from the Błądzikowski stream to the puck lagoon (southern Baltic Sea, Poland) [commun.]

Damaszke M., Szymczak E.

Oceanological and Hydrobiological Studies

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2013

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Vol. 42, No. 2

216-224

EN

The main aim of this study was to determine the size of the load carried by the Błądzikowski Stream and discharged into the Puck Lagoon, and the role of the river load in the formation of the sea bed deposits at the stream mouth. The Błądzikowski Stream, with the length of only 10 km, discharges about 610 tons of sediment into the Puck Lagoon per year, including 89.8% (548 tons) of the bed load and 10.2% (62 tons) of the suspended load. The amount is 4.9% of the river load discharged into the Puck Lagoon. Mineral particles are more common in the composition of the river load and account for 94.6% of the suspended load and 98.7% of the bed load. It is mainly the bed load deposited in the estuarine area that creates a contemporary underwater accumulation form in the Puck Lagoon, which is corroborated by the granulometric composition of the channel and surface sediments; the suspended load is carried further into the Lagoon.

5

Bed load transport by bed form migration

Aberle J., Coleman S., Nikora V.

Acta Geophysica

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2012

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Vol. 60, no. 6

1720-1743

EN

A theoretically-based methodology is presented for the determination of bed load transport from high-resolution measurements of bed surface elevations for steady-state or developing dunes. The methodology is based on the general form of the Exner equation for sediment continuity and requires information on the distribution of sediment volume concentration as well as the migration velocity of bed layers. In order to determine layer speeds, a new method based on cross-correlation analysis of elevation slices is proposed. The methodology is tested using artificiallycreated data as well as data from a physical model and from a flume study of developing bed forms. The analyses show the applicability of the method to determine bed load transport without the need to introduce assumptions about the form of the migrating surface. It is shown that predicted transport rates match measured or theoretical transport rates for steadily moving bed forms of an arbitrary shape. The method can also be used to predict transport rates over deforming bed forms, with the reasons for potential deviations between predicted and measured or theoretical transport rates for deforming bed forms identified and discussed. It is further shown that a simplified bulk-surface approach, that is relatively straightforward to apply and in which it is assumed that bed-layer velocity is constant with depth, gives results that are comparable to analyses based on determined bed-layer velocity variation with depth.

6

The transport and distribution of the river load from the Kacza River into the Gulf of Gdańsk (Southern Baltic Sea, Poland)

Szymczak E., Rhode D., Piekarek-Jankowska H.

Oceanological and Hydrobiological Studies

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2011

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Vol. 40, No.4

1-10

EN

The results of measurements of suspended sediment and bed load carried by the Kacza River into the Gulf of Gdańsk are discussed. The investigations were conducted in the years 2009–2010 at the Orłowo transect and at the mouth of the Kacza River in the Gulf of Gdańsk. The research has shown that the Kacza River discharged about 673 tons of sediment annually to the Gulf of Gdańsk, with 77% being transported as bed load. The granulometric composition of the river load is dominated by coarse-grained sand fractions.

7

Transport rumowiska wleczonego i skład jakościowy osadów dennych Potoku Jałowieckiego w Beskidzie Makowskim (Karpaty polskie)

Radecki-Pawlik A., Florencka N.

Inżynieria Środowiska / Akademia Górniczo-Hutnicza im. S. Staszica w Krakowie

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2001

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T. 6, z. 2

385-397

PL

W pracy przedstawiono wyniki badań chemicznych rumowiska dennego zgromadzonego w łachach korytowych potoku górskiego płynącego przez zlewnię położoną na obszarze wiejskim pod kątem ewentualnej akumulacji metali ciężkich w występujących w korycie potoku utworach aluwialnych. Stwierdzono, że największa ilość akumulowanych pierwiastków chemicznych odkłada się w rumowisku najdrobniejszym, w miejscach ocienionych naturalnymi wychodniami skalnymi, gdzie wymiana materiału następuje wyłącznie podczas przepływów ponadkorytowych i jest to Pb oraz Cd. Dodatkowo wykonano obliczenia transportu rumowiska wleczonego metodą Parkera oraz unoszonego metodą DRUSLE.

EN

The paper presents the field research of heavy metals accumulation in point bars and sediments. The research was undertaken in Jałowiecki mountain stream - Polish Carpathian mountainous region. It was found that in some tiny sediments situated within shadow of mega-clusters or rocks there is a tendency to accumulate heavy metals, especially Pb and Cd. Additionally bed load transport was calculated using Parker method and suspended load using DR-Usle concept.