The origin of a metalimnetic chrysophyte peak

A metalimnetic chlorophyll peak (40-70 pg.liter-*) in Jacks Lake, Ontario, was due primarily to a colonial chrysophyte, Chrysosphaerella longispina. The peak was not the result of in situ growth, nor of a passive and progressive accumulation of epilimnetic cells. Instead, a sudden bloom of the algae which occurred in the epilimnion at the end of June, possibly due to excystment, descended rapidly and within no more than 4 days concentrated in a narrow band below the thermocline. There was no net increase in chlorophyll a or cell biomass with time once the population was established in this region. No dividing cells were observed. After about 2 weeks the Chl a concentration at the peak began to decline and the peak disappeared by the end of August. The importance of metalimnetic peaks is greatly exaggerated by the measurement of Chl a.

[1]  A. J. Brook,et al.  OPTICAL DENSITY PROFILES AS AN AID TO THE STUDY OF MICROSTRATIFIED PHYTOPLANKTON POPULATIONS IN LAKES. , 1971 .

[2]  J. A. Hellebust,et al.  THE STATOSPORE OF DINOBRYON DIVERGENS IMHOF: FORMATION AND GERMINATION IN A SUBARCTIC LAKE 1 , 1975 .

[3]  N. Jerlov.  Maxima in the vertical distribution of particles in the sea , 1958 .

[4]  E. Nielsen,et al.  Light Adaptation in Marine Phytoplankton Populations and Its Interrelation with Temperature , 1959 .

[5]  D. E. Ketcham,et al.  Observations On Subsurface Distributions Of Chlorophyll a And Phytoplankton Carbon In The Northeast Pacific Ocean , 1974 .

[6]  C. D. Sandgren,et al.  CHARACTERISTICS OF SEXUAL AND ASEXUAL RESTING CYST (STATOSPORE) FORMATION IN DINOBRYON CYLINDRICUM IMHOF (CHRYSOPHYTA) 1 , 1981 .

[7]  M. Fiala,et al.  Production primaire au niveau de la thermocline en zone néritique de Méditerranée Nord-Occidentale , 1972 .

[8]  C. Lorenzen,et al.  A method for the continuous measurement of in vivo chlorophyll concentration , 1966 .

[9]  D. Lean,et al.  Phosphate Exchange and Organic Phosphorus Excretion by Freshwater Algae , 1976 .

[10]  J. H. Carpenter.  THE CHESAPEAKE BAY INSTITUTE TECHNIQUE FOR THE WINKLER DISSOLVED OXYGEN METHOD , 1965 .

[11]  T. Parsons,et al.  A practical handbook of seawater analysis , 1968 .

[12]  J. Steele,et al.  The vertical distribution of chlorophyll , 1960, Journal of the Marine Biological Association of the United Kingdom.

[13]  B. Burnison,et al.  Modified Dimethyl Sulfoxide (DMSO) Extraction for Chlorophyll Analysis of Phytoplankton , 1980 .

[14]  J. Kremer,et al.  Origins of vertical patterns of phytoplankton and nutrients in the temperate, open ocean: a stratigraphic hypothesis , 1981 .

[15]  J. Strickland.  A practical hand-book of seawater analysis , 1972 .

[16]  S. Ichimura,et al.  On the Oxygen and Chlorophyll Maxima Found in the Metalimnion of a Mesotrophic Lake , 1968 .

[17]  E. Fee.  The vertical and seasonal distribution of chlorophyll in lakes of the Experimental Lakes Area, northwestern Ontario: Implications for primary production estimates , 1976 .

[18]  G. C. Anderson.  SUBSURFACE CHLOROPHYLL MAXIMUM IN THE NORTHEAST PACIFIC OCEAN1 , 1969 .

[19]  H. Utermöhl.  Zur Vervollkommnung der quantitativen Phytoplankton-Methodik , 1958 .

[20]  F. Denoyelles,et al.  Analysis of the Response of Hypolimnetic Phytoplankton in Continuous Culture to Increased Light or Phosphorus Using Track Autoradiography , 1980 .

[21]  R. Eppley,et al.  A STUDY OF PLANKTON DYNAMICS AND NUTRIENT CYCLING IN THE CENTRAL GYRE OF THE NORTH PACIFIC OCEAN1 , 1973 .