Photosynthetic pigment ratios in relation to photic flux

The molar and weight ratios of the photosynthetic pigments of ten algal species were analyzed in an attempt to determine if knowledge of the light field could be used to give better ratios for estimating the chlorophyll a contributed from each algal division to total chlorophyll a or biomass. High performance liquid chromatography (HPLC) is one of the tools used in pigment-based chemotaxonomy for estimating the biomass of algal communities by determining the concentrations of the various chlorophylls and carotenoids. Stable ratios of chlorophyll a: marker pigment are used as multiplying factors for calculating the amount of chlorophyll a contributed from each major algal group to total chlorophyll a. Stable chlorophyll a: marker pigment ratios are not always easy to determine, so light field was investigated as a factor for determining consistently reliable ratios. This data will serve to determine new chlorophyll a: marker pigment ratios, as well as to verify or suggest changes to the existing ratios that are currently being used by our research group. An unknown pigment was isolated from Scytonema sp. grown in higher light fields and the ecological significance of this pigment was assessed.