Sudden instream releases of hypolimnetic water from hydropower plants (i.e., hydropeaking) can cause abrupt temperature variations (i.e., thermopeaking), typically on a daily basis. The propagation of the discharge and thermal waves are asynchronous, causing the benthic community to undergo two distinct but consecutive impacts. Invertebrates are known to respond to sudden increases in discharge with catastrophic drift, and recently have been shown to respond to sudden changes of temperature with drift, which is probably behavioral. Due to the decoupling of the discharge and thermal waves, catastrophic and behavioral drift can occur as distinct events. We analyzed the induction of drift in benthic invertebrates caused by a hydropeaking wave followed by a thermopeaking wave, in two open air flumes directly fed by an Alpine stream. The slight but abrupt increase in discharge caused a maximum 28 and 24-fold peak increases in drift in the two flumes, and the abrupt decrease in temperature caused an increase of 36 and 198-fold in the same flumes. In both flumes drift propensity increased during hydropeaking and thermopeaking simulations, and was higher during the latter.

Maiolini, B.; Bruno, M.C.; Carolli, M. (2011). Multiple drift responses of benthic invertebrates to hydropeaking waves. In: EUROMECH Colloquium 523: Ecohydraulics: linkages between hydraulics, morphodynamics and ecological processes in rivers,Clermont-Ferrand, France, 15-17 June 2011: 43-47. url: http://euromech_colloquium_523.igb-berlin.de/euromech-documents/EUROMECH-523_EXTENDED-ABSTRACTS.pdf handle: http://hdl.handle.net/10449/21726

Multiple drift responses of benthic invertebrates to hydropeaking waves

Maiolini, Bruno;Bruno, Maria Cristina;Carolli, Mauro
2011-01-01

Abstract

Sudden instream releases of hypolimnetic water from hydropower plants (i.e., hydropeaking) can cause abrupt temperature variations (i.e., thermopeaking), typically on a daily basis. The propagation of the discharge and thermal waves are asynchronous, causing the benthic community to undergo two distinct but consecutive impacts. Invertebrates are known to respond to sudden increases in discharge with catastrophic drift, and recently have been shown to respond to sudden changes of temperature with drift, which is probably behavioral. Due to the decoupling of the discharge and thermal waves, catastrophic and behavioral drift can occur as distinct events. We analyzed the induction of drift in benthic invertebrates caused by a hydropeaking wave followed by a thermopeaking wave, in two open air flumes directly fed by an Alpine stream. The slight but abrupt increase in discharge caused a maximum 28 and 24-fold peak increases in drift in the two flumes, and the abrupt decrease in temperature caused an increase of 36 and 198-fold in the same flumes. In both flumes drift propensity increased during hydropeaking and thermopeaking simulations, and was higher during the latter.
Temperature
Hydropower
Benthos
Streams
Alps
2011
Maiolini, B.; Bruno, M.C.; Carolli, M. (2011). Multiple drift responses of benthic invertebrates to hydropeaking waves. In: EUROMECH Colloquium 523: Ecohydraulics: linkages between hydraulics, morphodynamics and ecological processes in rivers,Clermont-Ferrand, France, 15-17 June 2011: 43-47. url: http://euromech_colloquium_523.igb-berlin.de/euromech-documents/EUROMECH-523_EXTENDED-ABSTRACTS.pdf handle: http://hdl.handle.net/10449/21726
File in questo prodotto:
File Dimensione Formato  
EUROMECH_Clermont-Fd_15-17June11_maiolini et al.pdf

accesso aperto

Licenza: Tutti i diritti riservati (All rights reserved)
Dimensione 90.66 kB
Formato Adobe PDF
90.66 kB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10449/21726
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact