Hydromorphological variability of a large lowland river based on the Hydromorphological Index for Rivers (HIR) basing on the Warta River

Abstract

The article presents the results of hydromorphological research of the Warta river basing of the Hydromorphological Index for Rivers (HIR). The HIR index considered as well as two components of this mutimetrix: hydromorphological diversity index (WRH) and modification transformation index (WPH).Field surveys were carried out in 2017-2018 on 49 survey sites of the Warta River. Studies have shown the diversification of the hydromorphological state of the river. Hydromorphological state of the surveyed sites from very good to bad was found. Good hydromorphological status (26 sites), for the most frequent category, followed by very good (10) and moderate (7). Poor conditions were detected for 5 sites and bad for one only. Statistically significant relationships were also found between the land use of the bank zone, and hydromorphological indices – HIR, WRH and WPH. The best hydromorphological conditions were found in semi-natural and agricultural areas. However, various forms of anthropopressure, with particular emphasis on urbanization, were factors significantly worsening the hydromorphological conditions. A higher degree of hydromorphological degradation was revealed in the lower course of the river comparing with the higher course of the Warta.

Keywords

• hydromorphological diversity
• lowland river
• anthropopressure
• hydromorphology
• hir