The use of the delayed luminescence method for determinations of chlorophyll a concentrations in phytoplankton

Abstract

Delayed luminescence is the phenomenon of long-lived emission of light by living plants and cyanobacteria after being illuminated with light and put into darkness. This study presents uses of this phenomenon as a tool for monitoring the chlorophyll a concentration in phytoplankton. The luminescence method was used on natural phytoplankton from the surface waters in tributaries supplying Lake Miedwie and compared with the commonly used spectrophotometric method of determining chlorophyll a concentrations.

Applications of Delayed Fluorescence from Photosystem II

“…For the DF-based method, there is no need to prepare samples, and it can be used in the laboratory or on-line to monitor the development of algae assemblage. Prokowski tried to use DF as a tool for monitoring chlorophyll a concentration in phytoplankton [ 83 ]. Different from other luminescence methods to determine chlorophyll a concentration [ 84 – 86 ], the DF-based method did not demand frequent and troublesome calibration.…”

Application of the Long-Term Delayed Luminescence for Study of Natural Water Environments

“…An additional way of limiting the impact of some of those factors is blocking electron transport in the photosynthetic apparatus of algae by adding a specific electron transport inhibitor to photosystem II of the sample, e.g. atrazine or 3-[3,4-dichlorophenyl]-1,1-dimethylurea (DCMU) (Prokowski, 1991(Prokowski, , 2009). The inhibitors increase intensity of the DL Chla fast components and reduce changes during excitation and eliminate DL Chla slow components (Prokowski, 1991(Prokowski, , 1999.…”

“…Previously, luminometers registering intensity of the DL Chla fast component after a predefined exposure of algae suspension incubated in darkness were used for assessing Chla content in phytoplankton (Wiltshire et al, 1998). Alternatively white light of small photons flux was used for that purpose (Prokowski, 2009). The exposure time is adjusted to register intensity of the component during temporary maximum at the induction curve (Fig.…”

“…White or monochromatic light is used for DL Chla excitation. The signal registered is DL intensity (Prokowski, 2009;Wiltshire et al, 1998) or, in the case of luminometers capable of determining the excitation spectrum of phytoplankton, total intensity for particular wavelength of the excitation light (Yacobi et al, 1998). It was proved that in the case of a defined algae culture its DL Chla intensity is a linear function of Chla concentration through 5 order magnitudes (Krause et al, 1982).…”