A comparison of the channel geomorphic unit composition of regulated and unregulated reaches in the Soča river

Ian  Maddock; Nataša  Smolar Žvanut; Graham  Hill

doi:10.18690/rg.2.1.2900

Ian Maddock University of Worcester, Department of Applied Sciences, Geography and Archaeology https://orcid.org/0000-0001-5072-8700
Nataša Smolar Žvanut Limnos Water Ecology Group; Institute for Water of the Republic of Slovenia
Graham Hill University of Worcester, Department of Applied Sciences, Geography and Archaeology

DOI: https://doi.org/10.18690/rg.2.1.2900

Keywords: Soča River, river regulation, habitat mapping, channel geomorphic unit, river hydraulics, river morphology

Abstract

This paper examines the effects of flow regulation on the size, spatial distribution and connectivity of channel geomorphic units (CGU) in the Soča River, Slovenia. A river channel survey was completed along three reaches, i.e. an unregulated reach (reach 1), and two regulated reaches with lower discharges, (reach 2 and 3). Results demonstrated significant differences in the CGU composition between the unregulated and regulated reaches. Flow regulation in the Soča River alters the dominant types of CGU’s present, significantly reduces the size of CGU’s, and affects the longitudinal distribution of types by reducing habitat connectivity and creating greater habitat fragmentation.

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Author Biographies

Ian Maddock, University of Worcester, Department of Applied Sciences, Geography and Archaeology

Worcester, United Kingdom. Email: i.maddock@worc.ac.uk.

Nataša Smolar Žvanut, Limnos Water Ecology Group; Institute for Water of the Republic of Slovenia

Ljubljana, Slovenia. Email: natasa@limnos.si.

Graham Hill, University of Worcester, Department of Applied Sciences, Geography and Archaeology

Worcester, United Kingdom. Email: g.hill@worc.ac.uk.

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