Abstract
AbstractClimate change asks for the reduction in the consumption of fossil‐based fuels and an increased share of non‐regulated renewable energy sources, such as solar and wind power. In order to back up a larger share of these intermittent sources, ‘battery services’ are needed, currently provided only in large scale by hydropower, leading to more rapid and frequent changes in flows (hydropeaking) in the downstream rivers. Increased knowledge about the ecosystem response to such operations and design of cost‐effective measures is needed.We analysed the response of fish communities to hydropeaking (frequency, magnitude, ramping rate and timing) and the interaction with the habitat conditions in Austrian rivers. An index of biotic integrity (Fish Index Austria) was used to compare river sections with varying degrees of flow fluctuations under near‐natural and channelized habitat conditions. The results showed that habitat conditions, peak frequency (number of peaks per year), ramping rate (water level variation) and interaction between habitat and ramping rate explained most of the variation of the Fish Index Austria. In addition, peaking during the night seems to harm fish more than peaking during the day. Fish communities in hyporhithral and epipotamal types of rivers are more affected by hydropeaking than those in metarhithral type of rivers. The results support the findings of other studies that fish stranding caused by ramping rates >15 cm h−1 are likely to be the main cause of fish community degradation when occurring more often than 20 times a year. While the ecological status degrades with increasing ramping rate in nature‐like rivers, fish communities are heavily degraded in channelized rivers regardless of the ramping rate. The mitigation of hydropeaking, therefore, requires an integrative approach considering the combined effects of hydrological and morphological alterations on fish. © 2014 The Authors. River Research and Applications published by John Wiley & Sons, Ltd.
Highlights
Climate change asks for the reduction in the consumption of fossil-based fuels and an increased share of renewable energy sources
Hydromorphological conditions of fish habitats are a consequence of the interplay between hydrological and morphological processes
Our results demonstrate that fish react to a combination of peak frequency, ramping rate and habitat conditions
Summary
Climate change asks for the reduction in the consumption of fossil-based fuels and an increased share of renewable energy sources. Several countries have launched ambitious programmes to stimulate further development renewables, and European Union (EU) has agreed upon the Renewable Energy Sources Directive (EU RES Directive, 2009). Renewable sources such as solar and wind power will, provide non-regulated power, that is, only producing energy during favourable climatic conditions. An increased share of non-regulated renewables will lead to a larger need for intermittent power, a service that currently only hydropower can provide in large scale (IPCC, 2012). Among the hydromorphological pressures, hydropeaking has been identified as one of the key threats for fish populations in Alpine rivers (Table I)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
