Title :

Stream periphyton photoacclimation response in field conditions: effect of community development and seasonal changes

Author(s) :

Laviale, M. [Auteur]
Génétique et évolution des populations végétales [GEPV]
Prygiel, J. [Auteur]
Lemoine, Yves [Auteur]
Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 [LOG]
Courseaux, Adeline [Auteur]
Génétique et évolution des populations végétales [GEPV]
Créach, A. [Auteur]
Génétique et évolution des populations végétales [GEPV]

Journal title :

Journal of Phycology

Pages :

1072-1082

Publisher :

Wiley

Publication date :

2009

ISSN :

0022-3646

HAL domain(s) :

Sciences du Vivant [q-bio]/Génétique/Génétique des populations [q-bio.PE]

English abstract : [en]

The photochemical behavior of intact stream periphyton communities in France was evaluated in response to the time course of natural light. Intact biofilms grown on glass substrata were collected at three development stages ...
Show more >The photochemical behavior of intact stream periphyton communities in France was evaluated in response to the time course of natural light. Intact biofilms grown on glass substrata were collected at three development stages in July and November, and structural parameters of the biofilms were investigated (diatom density and taxonomy). At each season, physiological parameters based on pigment analysis (HPLC) and pulse-amplitude-modulated (PAM) chl fluorescence technique were estimated periodically during a day from dawn to zenith. Regardless of the community studied, the optimal quantum yield of PSII (Fv ⁄ Fm), the effective PSII efficiency (FPSII), the nonphotochemical quenching (NPQ), and the relative electron transport rate (rETR) exhibited clear dynamic patterns over the morning. Moreover, microalgae responded to the light increase by developing the photoprotective xanthophyll cycle. The analysis of P-I parameters and pigment profiles suggests that July communities were adapted to higher light environments in comparison with November ones, which could be partly explained by a shift in the taxonomic composition. Finally, differences between development stages were significant only in July. In particular, photoinhibition was less pronounced in mature assemblages, indicating that self-shading (in relation to algal biomass) could have influenced photosynthesis in older communities.Show less >

Language :

Anglais

Peer reviewed article :

Oui

Audience :

Internationale

Popular science :

Non

Collections :

• Laboratoire d'Océanologie et de Géosciences (LOG) - UMR 8187

Source :

Harvested from HAL