Photoadaptive response during the development of a coastal Antarctic diatom bloom and relationship to water column stability
Moline, Mark A.
Limnol. Oceangr. 43:146-153

The raio of the xanthophylll pigments diadinoxanthin and diatoxanthin to chlorophyll a [(DD+DT}:Chl a] was used as a photoadaptive index during the development of a large Antarctic diatom bloom. This index was found to track fluctuations in the incident solar irradiance and the in situ light field over a 3 order magnitude change in the water column biomass. Depth profiles of the (DD+DT}:Chl a ratio showed that the upper mixed layer, assessed by physical data, was in fact stable over the course of the month. Diel experiments conducted over the same period showed a delayed (5-8 h) response of the DD+DT pool to the instantaneous Qpar (400-700 nm) irradiance. These time series results illustrate the potential use of xanthophyll pigmnents in assessing phytoplankton light histories and the degree of water column stability.