Please use this identifier to cite or link to this item: http://hdl.handle.net/10553/50876
Title: Light effects and diel variations of nitrate reductase activity in phytoplankton from the northwest Africa upwelling region
Authors: Martinez, Rosa
Packard, Theodore T. 
Blasco, Dolors
UNESCO Clasification: 251001 Oceanografía biológica
Issue Date: 1987
Publisher: 0198-0149
Journal: Deep-Sea Research, Part A: Oceanographic Research Papers 
Abstract: Light kinetics and diel cycles of nitrate reductase (NR) activity were studied in the upwelling ecosystem off northwest Africa. The activity of the enzyme showed a strong response to light at low intensities but became saturated at light intensities above 15–30% of the incident light intensity. At higher irradiances, NR activity showed photoinhibition. At sea surface irradiances an average inhibition of 32% in the NR activity was observed. Diel cycles of NR activity exhibited the following characteristics: a low pre-dawn value (0.03–0.009 μmol NO3−N (μg Chl α)−1), a rapid increase with the onset of daylight, a maximum before noon (tripling the dark value), a secondary maximum in the early afternoon, and an afternoon-evening decrease that coincided with the decrease in sunlight. To simulate these characteristics a continuous polynomial function of light and time was developed
URI: http://hdl.handle.net/10553/50876
ISSN: 0198-0149
DOI: 10.1016/0198-0149(87)90034-3
Source: Deep Sea Research Part A, Oceanographic Research Papers [ISSN 0198-0149], v. 34, p. 741-753
Appears in Collections:Artículos
Show full item record

SCOPUSTM   
Citations

6
checked on May 9, 2021

Page view(s)

34
checked on May 11, 2021

Google ScholarTM

Check

Altmetric


Share



Export metadata



Items in accedaCRIS are protected by copyright, with all rights reserved, unless otherwise indicated.