Quantum yield of the marine benthic microflora of near-shore coastal Penang, Malaysia

Abstract

Benthic microalgal communities often contribute more than 30% of the primary production of shallow coastal and estuarine areas. At Muka Head Penang (Pulau Pinang) and the Songsong Islands (Pulau Songsong), Kedah, Malaysia, high concentrations of suspended solids and phytoplankton biomass (10.6 mg Chl a m−3) has reduced water clarity such that the euphotic zone of these areas is less than 2 m and 3 m deep respectively. The benthic microalgal communities, which were composed of the diatom genera Cocconeis, Fragilaria, Paralia and Pleurosigma, had a low biomass, had low maximum quantum yields (0.325 ± 0.129), were poorly adapted to their light environment and were constantly light limited. These characteristics suggest that the benthic microalgal communities were likely to have made only a minor contribution to the total primary production of the area.

One pulse, one light curve: Fast characterization of the light response of microphytobenthos biofilms using chlorophyll fluorescence

“…The effects of initial light conditions on RLC parameters would likely be much larger if a light step shorter than 30 s had been used. In fact, most studies on benthic microalgae were based on RLCs use protocols use light steps of just 10 s (e.g., McMinn et al ; Serôdio et al ; Yun et al ; Lefebvre et al ; Du et al ). Also, the differences between RLCs and SSLCs would likely be larger if the later had been carried out applying light steps longer than 60 s, as it is the case of works targeting SSLCs using 2 min (Barranguet and Kromkamp ) or 3 min (Underwood et al ).…”

THE EFFECTS OF TEMPERATURE ON THE PHOTOSYNTHETIC PARAMETERS AND RECOVERY OF TWO TEMPERATE BENTHIC MICROALGAE, AMPHORA CF. COFFEAEFORMIS AND COCCONEIS CF. SUBLITTORALIS (BACILLARIOPHYCEAE)1

“…2004, Consalvey et al. 2005, McMinn et al. 2005), similar techniques were applied herein to determine the photosynthetic state of these organisms in stressed environments.…”

“…RLCs provide a snapshot of the physiological state of a plant and its ability to adapt its photosynthetic apparatus to rapid changes in irradiance. RLCs can be described using several characteristic parameters such as α (photosynthetic efficiency), rETR max (relative electron transport rate), and E k (photoacclimation index) (Ralph and Gademann 2005) by fitting the rETR and irradiance data to a single exponential decay function (McMinn and Hegseth 2004, McMinn et al. 2005, Ralph and Gademann 2005).…”

Measuring Photophysiology of Attached Stages of Colacium sp. by a Cuvette-Type Fast Repetition Rate Fluorometer v1

“…Given the development of PAM fluorometers, including the cuvette-type, for a broad range of subjects 11 , PAM fluorometers are still more common than the FRRf in algal photophysiology research 12 . For example, although the sample chamber structure and cuvette capacity between these tools only differs slightly, the cuvette-type PAM has been applied to phytoplankton [13][14][15] , benthic microalgae [16][17][18] , ice algae 19 , and epizoic algae 20 , while the cuvette-type FRRf has been applied primarily to phytoplankton [21][22][23] and a limited number of ice algae species 24,25 . Given its effectiveness, cuvette-type FRRf is equally applicable to benthic and epizoic algae.…”