<abstract xmlns="http://www.w3.org/1999/xhtml"><p>The main objective of the paper was to propose and evaluate the performance of a regional approach to estimate <italic>CN</italic> values and to test the impact of different initial abstraction ratios. The curve number (<italic>CN</italic>) was analyzed for five Slovak and five Polish catchments situated in the Carpathian Mountains. The L-moment based method of Hosking and Wallis and the ANOVA test were combined to delineate the area in two homogenous regions of catchments with similar <italic>CN</italic> values. The optimization condition enabled the choice of the initial abstraction ratio, which provided the smallest discrepancy between the tabulated and estimated <italic>CN</italic>s and the antecedent runoff conditions. The homogeneity in the <italic>CN</italic> within the regions of four Slovak and four Polish catchments was revealed. Finally, the regional <italic>CN</italic> was proposed to be at the 50% quantile of the regional theoretical distribution function estimated from all the <italic>CN</italic>s in the region.</p><p>The approach is applied in a group of Slovak and Polish catchments with physiographic conditions representative for the Carpathian region. The main benefit of introducing a common regional <italic>CN</italic> is the opportunity to apply this procedure in catchments of similar soil-physiographic characteristics and to verify the existing tabulated <italic>CN.</italic> The paper could give rise to an alternative way of estimating the <italic>CN</italic> values in forested catchments and catchments with a lack of data or without observations.</p></abstract>

The main objective of the paper was to propose and evaluate the performance of a regional approach to estimate CN values and to test the impact of different initial abstraction ratios. The curve number (CN) was analyzed for five Slovak and five Polish catchments situated in the Carpathian Mountains. The L-moment based method of Hosking and Wallis and the ANOVA test were combined to delineate the area in two homogenous regions of catchments with similar CN values. The optimization condition enabled the choice of the initial abstraction ratio, which provided the smallest discrepancy between the tabulated and estimated CNs and the antecedent runoff conditions. The homogeneity in the CN within the regions of four Slovak and four Polish catchments was revealed. Finally, the regional CN was proposed to be at the 50% quantile of the regional theoretical distribution function estimated from all the CNs in the region.The approach is applied in a group of Slovak and Polish catchments with physiographic conditions representative for the Carpathian region. The main benefit of introducing a common regional CN is the opportunity to apply this procedure in catchments of similar soil-physiographic characteristics and to verify the existing tabulated CN. The paper could give rise to an alternative way of estimating the CN values in forested catchments and catchments with a lack of data or without observations.

The L-moment based regional approach to curve numbers for Slovak and Polish Carpathian catchments

Faculty of Civil Engineering, Department of Land and Water Resources Management

Department of Water Engineering and Environment Restoration Faculty of Civil and Environmental Engineering

Journal of Hydrology and Hydromechanics

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

The main objective of the paper was to propose and evaluate the performance of a regional approach to estimate CN values and to test the impact of different...

The L-moment based regional approach to curve numbers for Slovak and Polish Carpathian catchments

Published Online: May 26, 2020

Page range: 170 - 179

Received: Jul 30, 2019

Accepted: Jan 12, 2020

DOI: https://doi.org/10.2478/johh-2020-0004

Keywords
Catchment curve number, Homogeneity, Regional frequency analysis

© 2020 Silvia Kohnová et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

The L-moment based regional approach to curve numbers for Slovak and Polish Carpathian catchments

Published Online: May 26, 2020

Page range: 170 - 179

Received: Jul 30, 2019

Accepted: Jan 12, 2020

DOI: https://doi.org/10.2478/johh-2020-0004

KeywordsCatchment curve number, Homogeneity, Regional frequency analysis

© 2020 Silvia Kohnová et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
Catchment curve number, Homogeneity, Regional frequency analysis