Abstract
Phytoplankton assemblages were collected during spring blooms in 1982 in Washington State and in Hawaii. Sinking rate responses of these assemblages were examined under nitrate, phosphate, and silicate depletion. Ambient nutrient concentrations, chlorophyll concentrations, photosynthetic rates, sinking rates, and floristic compositions were determined. Under nutrient-replete conditions, the temperate assemblage, composed primarily of large centric diatoms, had a sinking rate of 0.96 m d-1; sinking rates did not change appreciably over 4 d without nitrate. Without phosphate or silicate, the sinking rates remained constant for 3 d and then increased after biomass indices began to decline. These findings illustrate the potential importance of phosphate or silicate depletion to the sedimentation of spring-bloom diatom populations. The subtropical assemblage, composed primarily of diatoms, coccolithophorids, and dinoflagellates, had an initial sinking rate of 0.22 m d-1 and did not display substantial sinking rate changes in the absence of nitrate, phosphate or silicate. Floristic data consistently showed a proliferation of pennate diatoms, which had lower settling rates than centric diatoms. Growth and sedimentation patterns indicated a competitive advantage for pennate diatom components of subtropical assemblages; this in turn may limit phytoplankton sedimentation losses in such ecosystems.
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Literature cited
Anderson, L. and B. Sweeney: Diel changes in the sedimentation characteristics of Ditylum brightwelli, a marine centric diatom: changes in cellular lipids and effects of respiratory inhibitors and ion-transport modifiers. Limnol. Oceanogr. 22, 539–552 (1977)
Anderson, L. and B. Sweeney: Role of inorganic ions in controlling sedimentation rate of a marine centric diatom Ditylum brightwelli. J. Phycol. 14, 204–214 (1978)
Armstrong, F. A. J., C. R. Stearns and J. D. H. Strickland: Measurement of upwelling and subsequent biological processes by means of the Technicon AutoAnalyzer and associated equipment. Deep-Sea Res. 14, 381–389 (1967)
Bienfang, P. K.: Sinking rate dynamics of Crisophaera carterae Braarud. I. Effects of growth rate, limiting substrate, and diurnal variation in steady-state populations. J. exp. mar. Biol. Ecol. 49, 217–233 (1981a)
Bienfang, P. K.: Sinking rate dynamics of Crisophaera carterae Braarud. II. Senescence response to various limiting substrates in non-steady-state populations. J. exp. mar. Biol. Ecol. 49, 235–244 (1981b)
Bienfang, P. K.: Sinking rates of heterogeneous, temperate phytoplankton populations. J. Plankton Res. 3, 235–253 (1981c)
Bienfang, P. K.: SETCOL—a technologically simple and reliable method for measuring phytoplankton sinking rates. Can. J. Fish. aquat. Sciences 38, 1289–1294 (1981d)
Bienfang, P. K., P. J. Harrison and L. Quarmby: Sinking rate response to depletion of nitrate, phosphate and silicate in four marine diatoms. Mar. Biol. 67, 295–302 (1982)
Bienfang, P. K., E. A. Laws and W. Johnson: Phytoplankton sinking rate determination: technical and theoretical aspects, an improved methodology. J. exp. mar. Biol. Ecol. 30, 283–300 (1977)
Eppley, R. W., R. W. Holmes and E. Paasche: Periodicity in cell division and physiological behavior of Ditylum brightwelli, a marine planktonic diatom, during growth in light-dark cycles. Arch. Mikrobiol. 56, 305–323 (1967a)
Eppley, R. W., R. W. Holmes and J. D. H. Strickland: Sinking rates of marine phytoplankton measured with a fluorometer. J. exp. mar. Biol. Ecol. 1, 191–208 (1967b)
Hager, F. W., L. I. Gordon and J. K. Park: A practical manual for the use of the Technicon AutoAnalyzer in seawater nutrient analysis. Tech. Rep. Dep. Oceanogr. Ore. St. Univ., Corvallis 68–33, 1–31 (1968)
Harrison, P. J. and C. O. Davis: The use of outdoor phytoplankton continuous cultures to analyze factors influencing species selection. J. exp. mar. Biol. Ecol. 41, 9–23 (1979)
Harrison, P. J., R. W. Waters and F. J. R. Taylor: A broad spectrum artificial seawater medium for coastal and open ocean phytoplankton. J. Phycol. 16, 28–35 (1980)
Hasle, G. R.: The inverted microscope method. Monogr. oceanogr. Methodol. (UNESCO) 6, 88–96 (1978)
Iverson, R. L., H. F. Bittaker and V. B. Myers: Loss of radiocarbon in direct use of Aquasol for liquid scintillation counting of solutions containing 14C-NaHCO3. Limnol. Oceanogr. 21, 756–758 (1976)
Lean, D. R. S. and B. K. Burnison: An evaluation of errors in the 14C method of primary production measurement. Limnol. Oceanogr. 24, 917–928 (1979)
Murphy, J. and J. P. Riley: A modified simple solution method for the determination of phosphate in natural waters. Analytica chim. Acta 27, 31–36 (1962)
Smayda, T. J.: The suspension and sinking of phytoplankton in the sea. Oceanogr. mar. Biol. A. Rev. 8, 353–414 (1970)
Solórzano, L.: Determination of ammonia in natural waters by the phenohypochlorite method. Limnol. Oceanogr. 14, 799–801 (1969)
Steele, J. H. and C. S. Yentsch: The vertical distribution of chlorophyll. J. mar. biol. Ass. U.K. 39, 217–226 (1960)
Strickland, J. D. H. and T. R. Parsons: A practical handbook of seawater analysis, 2nd ed. Bull. Fish. Res. Bd Can. 167, 1–310 (1972)
Takahashi, M. and P. K. Bienfang: Size structure of phytoplankton biomass and photosynthesis in subtropical Hawaiian waters. Mar. Biol. 76, 203–211 (1983)
Utermöhl, H.: Zur Vervollkommnung der quantitativen Phytoplankton-Methodik. Mitt. int. Verein. theor. angew. Limnol. 9, 1–38 (1958)
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Communicated by N.D. Holland, La Jolla
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Bienfang, P.K., Harrison, P.J. Sinking-rate response of natural assemblages of temperate and subtropical phytoplankton to nutrient depletion. Mar. Biol. 83, 293–300 (1984). https://doi.org/10.1007/BF00397462
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DOI: https://doi.org/10.1007/BF00397462