Assessment of the Physical Habitat Suitability (PHS) for three autochthonous fish species in the Duero River (Spain) with the modelling tool IberHABITAT
Authors: Díaz-Redondo, M., Cortés Sánchez, F.M., & Molina Martín, B.
Congress: 39th IAHR World Congress. Granada, España.
First published: 2022
Abstract
The module IberHABITAT, developed for the 2D hydraulic model Iber, is based on the combination of both hydraulic and hydrobiological variables to create a habitat or eco-hydraulic model. This module allows to obtain classified areas of Physical Habitat Suitability (PHS) in the form of a Combined suitability index (C index: 0.0-1.0) for targeted fish species in relation to a specific discharge.
This particular approach has been applied in a 17.2 km-long pilot section of the Duero River between Toro and Zamora (Spain) within the DRAINAGE project for the integral management of flood risk. For the present study, the IberHABITAT modelling tool was run to obtain the SPH areas for three autochthonous fish species under four discharges: mean and minimum annual flow, and two ecological flows (ordinary conditions and drought conditions). The selection of the targeted fish species (Luciobarbus bocagei, Pseudochondrostoma duriensis and Squalius carolitertii), was based on previous surveys by the Duero River Basin Authority. A bathymetric survey was specifically obtained for this study, since the study area is characterized by complex geomorphology (bars, islands, pools, etc.).
Results on the C index were then classified into four categories and areas corresponding to the maximum category (4-Excellent conditions) were calculated. It is noteworthy that, under very low flow conditions, the most suitable areas for the adult and juvenile stages of B. bocagei are almost non-existent. At present, the recurrence of periods of minimum flows, as well as their duration, may be limiting the diversity of fish communities in the study section.
Download: Physical Habitat Suitability in the Duero River with IberHABITAT
Website: https://2022.iahrworldcongress.org/
