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HYDRAULIC PARAMETERS AND MORPHOMETRIC VARIABLES INTERACTIONS IN BEDROCK CHANNEL

100%

Biswas B. , Chandra Das B.

Quaestiones Geographicae

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2016

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tom 35

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nr 3

75-88

EN

Present study is on the interdependent nature of hydraulic parameters and morphometric variables of a bedrock river. In this study, using dumpy level, GPS, satellite images and some mathematical equations a data set on hydraulics and morphometric variables of a bedrock channel, named Bhatajhor, of eastern India was generated. That data set was used to (1) find out impulse-response relations between hydraulic variables (2) find out relations between morphometric variables and (3) find out relations between hydraulic and morphometric variables. Seven equations (5–11) were formulated based on this empirical study to the end. The seven empirical relations, most of which include only two variables, involve channel cross-section dimensions (area, width, mean depth, maximum depth, width/depth ratio, hydraulic radius), slope and hydraulic variables (velocity, kinetic energy, stream power, Manning’s n factor, Chezy’s C factor and shear stress). Observation shows relatively higher coefficient of determination (R2) between variables like velocity and Manning’s n factor (0.67), velocity and Chezy’s C factor (0.67), slope and τ (0.89), w/d ratio and hydraulic radius (0.53), slope and w/d ratio (0.50).

2

The effect of stream power in the instability and morphological changes of Haji Arab River, Buin Zahra (Qazvin Province, Iran)

86%

Hosseinzadeh M. M. , Khaleghi S. , Safari F. , Zarandini F. R.

Studia Quaternaria

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2023

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tom Vol. 40, Nr 1

25--35

EN

The stream power is one of the important river variables which is used in morphological analysis. Therefore, the stream power determines both erosion and deposition. This research examines the stream power, instability and morphometric changes of the channel using the annual geomorphic energy (AGE) in Haji Arab River in Buin Zahra (Qazvin Province). The AGE is calculated by integrating the relationship between the excess specific stream power and discharge using a flow duration curve. The AGE values for each reach should be either positive or negative. Therefore, according to the differentials in AGE values, depositional and erosional reach are determined. In this paper, the results of the AGE method were compared with the rapid geomorphic assessments (RGA), including the channel stability indicators (CSI) model and OSEPI index. Also, the RHS method based on the field works was used to identify depositional and erosional geomorphic landforms. Comparing the results of the AGE with rapid RGA indices, shows that results of the OSEPI are more consistent with the erosional and depositional status of the reaches, based on the AGE. Spatial variations in lithology and structure, when combined with the course of the Haji Arab River indicate that channel morphometry locally reflects geological factors that have caused slope differences in different reaches. The calculated AGE values at different cross-sections have significant variability, reflecting characteristic local variation in bed slope, cross-section geometry and bed-sediment composition.

3

The velocity-reversal hypothesis-implications for a mountainous stream bed morphology

86%

Radecki-Pawlik A.

Electronic Journal of Polish Agricultural Universities. Series Environmental Development

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2002

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tom 05

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nr 2

EN

This paper presents the results of a study of reversal hypothesis phenomena observed within riffles and pool sequences on a 1.1 km long reach of the Skawica-Jalowiecki Stream. The Skawica-Jalowiecki is a flashy mountain stream with an alluvial bed that transports sediment during frequent floods. The study reach is situated just below the border of the Babia-Gora National Park in Polish Carpathians, which provides a good, undisturbed research site. It was found that Q=4.27 m3s-1, Q=2.43 m3s-1 velocities and shear stresses in pools were highest over riffles during spring floods. It was also observed that unit stream power above the pools was bigger than that found in the riffles.

4

Dynamics of water flow on degraded sectors of Polish mountain stream channels

72%

Michalik A. , Ksiazek L.

Polish Journal of Environmental Studies

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2009

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tom 18

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nr 4

665-672

EN

Our study is aimed at determining the hydrodynamic changes of mountain stream channels caused by degradation that was initiated by uncontrolled mining of bed material. The study was conducted on Mszanka and Targaniczanka streams in which the collected data included: longitudinal profiles, cross-sections of the channels, the geometry of bed forms and analysis of particle composition of the bed material. The results show that hydrodynamic parameters have changed downstream from the studied sectors and along the cross-sections. Bed degradation also was linked to bank erosion, which intensified morphological changes of channels effecting the spatial distribution of flow velocity, shear stresses and stream power. The investigation also demonstrated that the bedload movement was in accordance with channel changes and more sediments were deposited than transported along the studied area. Finally, local aggradation and unstable channel capacity were observed.

5

Zmiana warunków hydrodynamicznych wzdłuż koryta potoku górskiego w zróżnicowanej zabudową techniczną małej zlewni karpackiej

58%

Radecki-Pawlik A.

Inżynieria Rolnicza

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2004

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tom R. 8, nr 2

21--33

PL

W pracy przedstawiono, w jaki sposób regulacja potoku górskiego wpływa na zmianę zasadniczych parametrów hydrodynamicznych przepływu, takich jak: prędkość dynamiczna, naprężenia styczne, liczba Froude’a i Reynoldsa, opory ruchu, moc strumienia oraz jednostkowa moc strumienia. Wykazano, że zabudowa bystrotokiem części koryta potoku górskiego znacznie zaburzyła warunki hydrodynamiczne cieku. Badaniami objęty został potok Młynne w Gorcach o częściowo zabudowanym korycie, a częściowo pozostającym w stanie naturalnym.

EN

The paper describes the way in which the river training influences such hydrodynamics stream conditions as shear velocity, shear stresses, stream power, unit stream power, Froude and Reynolds numbers and resistant coefficient. It was shown that after river training the hydrodynamics parameters in the trained part of the stream increased their value. The work is set up in the Młynne stream catchment in Polish Carpathians in Gorce Mountains.