Aspects of iron and nitrogen nutrition in the red tide dinoflagellateGymnodinium sanguineum

Abstract

Abstract. Iron-stress-mediated effects on biochemical constituents of the red tide dinoflagellate Gymnodinium sanguineurn Hirasaka were examined in 1988 by comparing Fe-replete and Fe-deplete batch cultures. The influence of nitrogen source (NO 3 or NH4) on characteristics of Fe-deplete cells was also studied [i.e., Fe-deplete/NO 3-grown (= -Fe/NO3) vs Fe-deplete/NH4-grown (= -Fe/ NH4) ]. Common to both N sources were reductions of chlorophyll a (chl a) and Fe quotas (per cell volume) by 75% and ca.

Aspects of iron and nitrogen nutrition in the red tide dinoflagellateGymnodinium sanguineum

“…In the preceding paper (Doucette and Harrison 1991), we demonstrated that iron depletion alters the biochemical composition of Gymnodinium sanguineum, a red tide species. However, both the extent and nature of these changes are, in fact, influenced strongly by nitrogen source (i.e., NO 3 or NH4).…”

“…of Oceanography, University of British Columbia) were maintained on enriched artificial seawater as described in the preceding paper (Doucette and Harrison 1991). of Oceanography, University of British Columbia) were maintained on enriched artificial seawater as described in the preceding paper (Doucette and Harrison 1991).…”

“…All experimental data were obtained from aliquots of those cultures utilized by Doucette and Harrison (1991) for assessment of biochemical composition. Samples employed were harvested from cultures immediately after those used to examine compositional variables.…”

“…Iron has often been implicated in the initiation of red tides (see Doucette andHarrison 1990, 1991). These dinoflagellate blooms are of ecological importance due not only to their apparent detrimental aspects, including toxin production and high BOD (biological oxygen demand) resulting in anoxia (Yentsch et al 1980, Taylor 1987, but also to their potential contribution to local primary production (Vargo et al 1987).…”

A preliminary study of the formation of a third category of cysts by a toxigenic dinoflagellate, Alexandrium fundyense in response to elevated concentrations of ammonium chloride

“…Iron has been shown to be one of the essential trace elements required for the occurrence of massive blooms of dinoflagellates (Doucette and Harrison, 1991). Blooming of marine micro algae (Naito et al, 2008;Wegner et al, 2006) in coastal waters has been attributed to the assimilation of nutrients including iron, made available via land run-off and aeolian sources.…”