Physicochemical sea ice and water characteristics near Point Barrow 2005-2006, supplement to: Manes, Sarah Story; Gradinger, Rolf (2009): Small scale vertical gradients of Arctic ice algal photophysiological properties. Photosynthesis Research, 102(1), 53-66

Photosynthetic parameters of phytoplankton and sea ice algae from landfast sea ice of the Chukchi Sea off Point Barrow, Alaska, were assessed in spring 2005 and winter through spring 2006 using Pulse Amplitude Modulated (PAM) fluorometry including estimates of maximum quantum efficiency (Fv/Fm), max...

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Bibliographic Details
Main Authors: Manes, Sarah Story, Gradinger, Rolf
Format: Article in Journal/Newspaper
Language:English
Published: PANGAEA - Data Publisher for Earth & Environmental Science 2009
Subjects:
IPY
Online Access:https://dx.doi.org/10.1594/pangaea.815928
https://doi.pangaea.de/10.1594/PANGAEA.815928
Description
Summary:Photosynthetic parameters of phytoplankton and sea ice algae from landfast sea ice of the Chukchi Sea off Point Barrow, Alaska, were assessed in spring 2005 and winter through spring 2006 using Pulse Amplitude Modulated (PAM) fluorometry including estimates of maximum quantum efficiency (Fv/Fm), maximum relative electron transport rate (rETRmax), photosynthetic efficiency (alpha), and the photoadaptive index (Ek). The use of centrifuged brine samples allowed to document vertical gradients in ice algal acclimation with 5 cm vertical resolution for the first time. Bottom ice algae (0-5 cm from ice-water interface) expressed low Fv/Fm (0.331-0.426) and low alpha (0.098-0.130 /(µmol photons/m**2/s)) in December. Fv/Fm and alpha increased in March and May (0.468-0.588 and 0.141-0.438 /(µmol photons/m**2/s), respectively) indicating increased photosynthetic activity. In addition, increases in rETRmax (3.3-16.4 a.u.) and Ek (20-88 µmol photons/m**2/s) from December to May illustrates a higher potential for primary productivity as communities become better acclimated to under-ice light conditions. In conclusion, photosynthetic performance by ice algae (as assessed by PAM fluorometry) was tightly linked to sea ice salinity, temperature, and inorganic nutrient concentrations (mainly nitrogen). : Data extracted in the frame of a joint ICSTI/PANGAEA IPY effort, see http://doi.pangaea.de/10.1594/PANGAEA.150150