Online Volumes of the Journal of Hydrology and Hydromechanics


J. Hydrol. Hydromech., Vol. 69, No. 3 - Early View, 2021, p. 1 - 9, doi: 10.2478/johh-2021-0012
Scientific Paper, English

Peter Šurda, Ľubomír Lichner, Jozef Kollár, Anton Zvala, Dušan Igaz: Evaluation of soil properties in variously aged Scots pine plantations established on sandy soil

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  • Pines are widely planted for sand dune stabilization and their cultivation results in the changes in physical, chemical, hydro-physical and water repellency properties. Soil properties were evaluated at three Scots pine plantations (PF1, PF2 and PF3) close to Studienka village, Borská nížina lowland (southwestern Slovakia) during hot and dry summer period. The PF1 site is a newly established plantation, the PF2 site is about 30 years old plantation, and the PF3 site is about 100 years old plantation. Here, we estimated the differences in pH, soil organic carbon content, Cox, particle size distribution, PSD, saturated, ks, and unsaturated, k(–2 cm), hydraulic conductivity, water, Sw, and ethanol, Se, sorptivity, water drop penetration time, WDPT, and repellency index, RI. It was found that Cox varies most significantly with plantation age, and relative differences in PSD and pH were lower than the relative difference in Cox. The PF3 site differs the most from the other two, especially in Cox and in the content of sand fraction. It can be attributed to the older age of the plantation, which represents a more advanced stage of succession accompanied by an accumulation of soil organic matter. Relationships between Cox, k(–2 cm), RI, and WDPT and pine forest age were described by appropriate mathematical models. We found a similarity between k(–2 cm) and RI relationships vs. pine forest age (exponential models), and between Cox and WDPT relationships vs. pine forest age (first and second-order polynomial models). The latter similarity can be supported by the fact that soil water repellency is induced by the hydrophobic and amphiphilic components of soil organic matter.

    KEY WORDS: Sandy soil; Scots pine; Plantation; Forest restoration; Soil water repellency; Soil hydrophysical properties.

    Address:
    - Peter Šurda, Institute of Hydrology, Slovak Academy of Sciences, Dúbravská cesta 9, SK-84104 Bratislava, Slovakia. (Corresponding author. Tel.: Fax.: Email: surda@uh.savba.sk)
    - Ľubomír Lichner, Institute of Hydrology, Slovak Academy of Sciences, Dúbravská cesta 9, SK-84104 Bratislava, Slovakia.
    - Jozef Kollár, Institute of Landscape Ecology, Slovak Academy of Sciences, Štefánikova 3, SK-81499 Bratislava, Slovakia.
    - Anton Zvala, Institute of Hydrology, Slovak Academy of Sciences, Dúbravská cesta 9, SK-84104 Bratislava, Slovakia.
    - Dušan Igaz, Department of Biometeorology and Hydrology, Faculty of Horticulture and Landscape Engineering, Slovak University of Agriculture, Tr. A. Hlinku 2, SK-94901 Nitra, Slovakia.

     




J. Hydrol. Hydromech., Vol. 69, No. 3 - Early View, 2021, p. 1 - 8, doi: 10.2478/johh-2021-0013
Scientific Paper, English

Václav Matoušek, Andrew Chryss, Lionel Pullum: Modelling vertical concentration distributions of solids suspended in turbulent visco-plastic fluid

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  • Vertical concentration distributions of solids conveyed in Newtonian fluids can be modelled using Rouse- Schmidt type distributions. Observations of solids conveyed in turbulent low Reynolds number visco-plastic carriers, suggest that solids are more readily suspended than their Newtonian counterparts, producing higher concentrations in the centre of the pipe. A Newtonian concentration profile model was adapted to include typical turbulent viscosity distributions within the pipe and particle motion calculated using non-Newtonian sheared settling. Predictions from this and the unmodified model, using the same wall viscosity, are compared with the chord averaged profile extracted from tomographic data obtained using a 50 mm horizontal pipe.

    KEY WORDS: Complex slurry flow; Non-Newtonian flow; Solids distribution; Pipe flow; Particle settling; Laboratory experiment.

    Address:
    - Václav Matoušek, Czech Technical University in Prague, Faculty of Civil Engineering, Department of Hydraulics and Hydrology, Thákurova 7, 166 29 Praha 6, Czech Republic. (Corresponding author. Tel.: Fax.: Email: v.matousek@fsv.cvut.cz)
    - Andrew Chryss, CSIRO Mineral Resources, Bayview Avenue, Clayton, Victoria 3168, Australia.
    - Lionel Pullum, 29 Monash Avenue, Olinda, Victoria 3788, Australia.

     




J. Hydrol. Hydromech., Vol. 69, No. 3 - Early View, 2021, p. 1 - 13, doi: 10.2478/johh-2021-0014
Scientific Paper, English

Jun Wang, Zhixing Hou, Hongjian Sun, Bihe Fang, Jueyi Sui, Bryan Karney: Local scour around a bridge pier under ice-jammed flow condition – an experimental study

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  • The appearance of an ice jam in a river crucially distorts local hydrodynamic conditions including water level, flow velocity, riverbed form and local scour processes. Laboratory experiments are used for the first time here to study ice-induced scour processes near a bridge pier. Results show that with an ice sheet cover the scour hole depth around a bridge is increased by about 10% compared to under equivalent open flow conditions. More dramatically, ice-jammed flows induce both greater scour depths and scour variability, with the maximum scour depth under an ice-jammed flow as much as 200% greater than under equivalent open flow conditions. Under an ice-jammed condition, both the maximum depth and length of scour holes around a bridge pier increase with the flow velocity while the maximum scour hole depth increases with ice-jam thickness. Also, quite naturally, the height of the resulting deposition dune downstream of a scour hole responds to flow velocity and ice jam thickness. Using the laboratory data under ice-jammed conditions, predictive relationships are derived between the flow’s Froude number and both the dimensionless maximum scour depth and the dimensionless maximum scour length.

    KEY WORDS: Ice jam; Ice cover; Riverbed deformation; Local scour; Bridge pier.

    Address:
    - Jun Wang, College of Civil and Hydraulic Engineering, Hefei University of Technology, 193 Tunxi Road, Hefei, Anhui, China.
    - Zhixing Hou, College of Civil and Hydraulic Engineering, Hefei University of Technology, 193 Tunxi Road, Hefei, Anhui, China.
    - Hongjian Sun, College of Civil and Hydraulic Engineering, Hefei University of Technology, 193 Tunxi Road, Hefei, Anhui, China.
    - Bihe Fang, College of Civil and Hydraulic Engineering, Hefei University of Technology, 193 Tunxi Road, Hefei, Anhui, China.
    - Jueyi Sui, School of Engineering, University of Northern British Columbia, 3333 University Way, Prince George, BC, Canada. (Corresponding author. Tel.: Fax.: Email: Jueyi.sui@unbc.ca)
    - Bryan Karney, Department of Civil Engineering, University of Toronto, Canada.

     




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Acta Hydrologica Slovaca
Institute of Hydrology SAS
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841 04 Bratislava
Slovak Republic
web: www.ih.sav.sk/ah

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