Use of a flow deflector to protect rheophilic fish spawning grounds during hydropeaking

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60077344%3A_____%2F23%3A00583943" target="_blank" >RIV/60077344:_____/23:00583943 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/60076658:12310/23:43906248 RIV/60076658:12520/23:43906248

Výsledek na webu

<a href="https://doi.org/10.1002/rra.4084" target="_blank" >https://doi.org/10.1002/rra.4084</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1002/rra.4084" target="_blank" >10.1002/rra.4084</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Use of a flow deflector to protect rheophilic fish spawning grounds during hydropeaking

Popis výsledku v původním jazyce

Rheophilic fishes are one of the ecological groups of fishes declining most quickly in number due to various habitat modifications and discharge regulations. Artificial rapid increases and decreases in discharge (hydropeaking) can cause severe damage to the eggs of rheophilic fishes. We investigated whether the effects of a water increase in hydropeaking on a spawning ground may be mitigated by a deflector installed at the top of the weir that diverts flow to other sections. At the research site, rheophilic asp (Leuciscus aspius) spawn annually in early spring, and their success might be affected by hydropeaking, with base discharge ranging from 3 to 7 m(3) x s(-1) and peak discharge ranging from 16 to 25 m(3) x s(-1) occurring 4 to 7 times during the asp spawning season and egg development period. To protect the adhesive eggs from detachment during peak discharge, a flow deflector (a wooden wall at the selected part of the weir) was installed to regulate discharge on the protected spawning ground. This measure allowed normal discharge under base flow conditions. During peak flow, a significant portion of the additional water was directed to the part of the river channel where egg abundance was lower and to the mill channel, where asp spawning was not present. While the total discharge increased 4.1 times compared to the base flow, the water discharge in the protected spawning ground increased only 2.7 times. This resulted in more than half of the asp eggs being retained in the protected channel. Although the use of such a measure is limited to specific local conditions where eggs are located just downstream of the weir, it can be a valid solution in highly fragmented rivers with hydropeaking and can lead to higher recruitment of rheophilic fishes.

Název v anglickém jazyce

Use of a flow deflector to protect rheophilic fish spawning grounds during hydropeaking

Popis výsledku anglicky

Rheophilic fishes are one of the ecological groups of fishes declining most quickly in number due to various habitat modifications and discharge regulations. Artificial rapid increases and decreases in discharge (hydropeaking) can cause severe damage to the eggs of rheophilic fishes. We investigated whether the effects of a water increase in hydropeaking on a spawning ground may be mitigated by a deflector installed at the top of the weir that diverts flow to other sections. At the research site, rheophilic asp (Leuciscus aspius) spawn annually in early spring, and their success might be affected by hydropeaking, with base discharge ranging from 3 to 7 m(3) x s(-1) and peak discharge ranging from 16 to 25 m(3) x s(-1) occurring 4 to 7 times during the asp spawning season and egg development period. To protect the adhesive eggs from detachment during peak discharge, a flow deflector (a wooden wall at the selected part of the weir) was installed to regulate discharge on the protected spawning ground. This measure allowed normal discharge under base flow conditions. During peak flow, a significant portion of the additional water was directed to the part of the river channel where egg abundance was lower and to the mill channel, where asp spawning was not present. While the total discharge increased 4.1 times compared to the base flow, the water discharge in the protected spawning ground increased only 2.7 times. This resulted in more than half of the asp eggs being retained in the protected channel. Although the use of such a measure is limited to specific local conditions where eggs are located just downstream of the weir, it can be a valid solution in highly fragmented rivers with hydropeaking and can lead to higher recruitment of rheophilic fishes.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10619 - Biodiversity conservation

Projekt

<a href="/cs/project/TJ02000012" target="_blank" >TJ02000012: Zvýšení přirozeného reprodukčního potenciálu rheofilních ryb na člověkem ovlivněných tocích</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2023

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

River Research and Applications

ISSN

1535-1459

e-ISSN

1535-1467

Svazek periodika

39

Číslo periodika v rámci svazku

3

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

9

Strana od-do

561-569

Kód UT WoS článku

000891201500001

EID výsledku v databázi Scopus

2-s2.0-85142873542