Vegetation on Fluvial Landforms along Near-Natural Reaches of the Opava, Černá Opava and Branná Rivers Ten Years after Extreme Flood Disturbance

Abstract

Riparian vegetation patterns and fluvial geomorphic forms and processes are very closely related environmental phenomena. This paper examines riparian vegetation patterns in relation to fluvial geomorphic landforms in five near-natural river reaches within ten years of a catastrophic flood. Extreme disturbance – the July 1997 flood – destroyed technically designed river channels and created suitable conditions for a number of ecosystems with high biodiversity and ecological stability. In summer 2007 (ten years after catastrophic flood), in five re-naturalized reaches, vegetation along with other environmental variables was collected on particular landform types (bars, islands, banks, floodplains and terraces). The analyses show that the key environmental determinants of riparian vegetation variation are the fluvial-geomorphic surfaces. The results suggest that many bottomland species of woody and herbaceous vegetation have predictable distribution patterns that correspond with observable fluvial landforms.