Journal of Phycology 

About: Journal of Phycology is an academic journal published by Wiley-Blackwell. The journal publishes majorly in the area(s): Population & Algae. It has an ISSN identifier of 0022-3646. Over the lifetime, 6187 publications have been published receiving 279117 citations. The journal is also known as: J. Phycol. & J Phycol.

Biovolume calculation for pelagic and benthic microalgae

Abstract: Microalgal biovolume is commonly calculated to assess the relative abundance (as biomass or carbon) of co-occurring algae varying in shape and/or size. However, a standardized set of equations for biovolume calculations from microscopically measured linear dimensions that includes the entire range of microalgal shapes is not available yet. In comparison with automated methods, the use of microscopical measurements allows high taxonomic resolution, up to the species level, and has fewer sources of error. We present a set of geometric shapes and mathematical equations for calculating biovolumes of >850 pelagic and benthic marine and freshwater microalgal genera. The equations are designed to minimize the effort of microscopic measurement. The similarities and differences between our proposal for standardization and previously published proposals are discussed and recommendations for quality standards given.

THE Si:C:N RATIO OF MARINE DIATOMS: INTERSPECIFIC VARIABILITY AND THE EFFECT OF SOME ENVIRONMENTAL VARIABLES1

Abstract: The variability of marine diatom Si:C and Si:N composition ratios was examined to assess their utility as ecological conversion factors. Twenty-seven diatom species grown under an 18:6 h LD cycle and sampled at the end of the light period gave mean ratios, by atoms, of 0.13 ± 0.04 and 1.12 ± 0.33 for Si:C and Si:N ratios, respectively (95% C.I. reported). The mean ratios for 18 species grown under continuous illumination were 0.12 ± 0.03 for Si:C and 0.95 ± 0.23 for Si:N. The mean ratios of the clones grown under constant light were not statistically different from those calculated for the same species grown under an 18:6 h LD photoperiod. The overall mean Si:C and Si:N ratios for the 18:6 h LD and continuous light experiments taken together, weighted by the number of species in each experiment, are 0.13 and 1.05, respectively. The average ratios for the nine nanoplankton species ( 20 μm) had higher mean ratios, Si:C = 0.15 ± 0.04 and Si:N = 1.20 ± 0.37. Time course sampling throughout a 24 h period revealed twofold variations in both ratios for individual species grown on a 14:10 h LD cycle. Changes in irradiance can also produce factor of two variations, both ratios being higher under low light. Comparisons of these data with those from the literature regarding the effects of temperature and nutrient limitation on diatom elemental composition suggest that use of these ratios to convert field estimates of biogenic silica into nitrogen or carbon units, or to estimate silica production from 14C data, should yield results accurate to within a factor of three under most circumstances.

Simple conditions for growth of unicellular blue‐green algae on plates

Abstract: The efficiencies of plating of 2 cultures of unicellular blue-green algae, 1 coccoid and 1 rod-shaped, were studied systematically. Reproducible colony growth and accurate viable counts are dependent on the use of a low agar concentration, and on the sterilization of the agar separately from the mineral components of the medium.

Yellow‐green algae with chlorophyllide c1,2

Abstract: SUMMARY Chlorophyllide c (chlorophyll c) wax found in axenic or unialgal cultures of 5 members of the class Xanthophyceae and in 2 members of the class Raphidophyceae (Chloromonadophyceae). Two other algae contained no chl c; neither had chl b. One of these plants, Pleurochloris magna, is presumably a member of the newly named class Eustigmatophyceae (Hibberd and Leedale). The other alga, clone GSB Sticho, is of uncertain, systematic position. Although, the xanthophyll pigments were not critically studied, there is enough evidence, to permit the conclusion that the xanthophyll suites of the chloromonads, the xanthophytes, P. magna, and clone GSB Sticho all differ in at least one respect.

Heavy metal–induced oxidative stress in algae†

Abstract: Heavy metals, depending on their oxidation states, can be highly reactive and, as a consequence, toxic to most organisms. They are produced by an expanding variety of anthropogenic sources suggesting an increasingly important role for this form of pollution. The toxic effect of heavy metals appears to be related to production of reactive oxygen species (ROS) and the resulting unbalanced cellular redox status. Algae respond to heavy metals by induction of several antioxidants, including diverse enzymes such as superoxide dismutase, catalase, glutathione peroxidase and ascorbate peroxidase, and the synthesis of low molecular weight compounds such as carotenoids and glutathione. At high, or acute, levels of metal pollutants, damage to algal cells occurs because ROS levels exceed the capacity of the cell to cope. At lower, or chronic, levels algae accumulate heavy metals and can pass them on to organisms of other trophic levels such as mollusks, crustaceans, and fishes. We review here the evidence linking metal accumulation, cellular toxicity, and the generation of ROS in aquatic environments.