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Two sets of triangular hydrographs were generated in a 12-m-long laboratory flume for two sets of initial bed conditions: intact and water-worked gravel bed. Flowrate ranging from 0.0013 m3 s-1 to 0.0456 m3 s-1, water level ranging from 0.02 m to 0.11 m, and cumulative mass of transported sediment ranging from 4.5 kg to 14.2 kg were measured. Then, bedload transport rate, water surface slope, bed shear stress, and stream power were evaluated. The results indicated the impact of initial bed conditions and flow unsteadiness on bedload transport rate and total sediment yield. Difference in ratio between the amount of supplied sediment and total sediment yield for tests with different initial conditions was observed. Bedload rate, bed shear stress, and stream power demonstrated clock-wise hysteretic relation with flowrate. The study revealed practical aspects of experimental design, performance, and data analysis. Water surface slope evaluation based on spatial water depth data was discussed. It was shown that for certain conditions stream power was more adequate for the analysis of sediment transport dynamics than the bed shear stress. The relations between bedload transport dynamics, and flow and sediment parameters obtained by dimensional and multiple regression analysis were presented.

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The macroinvertebrate fauna of the Młynne stream (Polish Carpathians) in the aspect of the bed load transport and water quality. The qualitative composition of the bottom sediments and the bed load and suspended load transport along the mountain stream were presented. The studies were carried on the Młynne stream in Gorce (Polish Carpathians). The streams flows partially in the natural river-bed and partially in the regulated with rapids. The stream bed load is accumulated in the reservoir up to the check dam and is qualitatively different from the load deposited at the bars. The taxonomic richness of the Młynne stream is a little bigger compared with the other investigated mountain and sub-mountain streams, but lesser compared with bigger rivers. The number of taxa on the natural reaches is more than double than on the regulated ones, with more taxa of high environmental demands and high values of the BMWP-PL index. The paper brings up the question of the environmental friendly technical solutions in different human activities in the sub-mountain and mountain river valleys, advantageous for humans and the river biological diversity (or resistance for negative environmental factors) as well. [ABSTRACT FROM AUTHOR]