Premium
GROWTH RATE RELATIONSHIPS TO PHYSIOLOGICAL INDICES OF NUTRIENT STATUS IN MARINE DIATOMS
Author(s) -
Clark Darren R.
Publication year - 2001
Publication title -
journal of phycology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.85
H-Index - 127
eISSN - 1529-8817
pISSN - 0022-3646
DOI - 10.1046/j.1529-8817.2001.037002249.x
Subject(s) - thalassiosira pseudonana , biology , thalassiosira weissflogii , relative growth rate , cmax , diatom , botany , zoology , nutrient , growth rate , phytoplankton , ecology , bioavailability , bioinformatics , geometry , mathematics
The growth of two species of marine diatom, Thalassiosira weissflogii (Grunow) and Thalassiosira pseudonana (Hustedt), was followed in batch cultures at four concentrations of dissolved inorganic carbon from N‐ and C‐replete lag phase into N‐ and/or C‐deplete stationary phase. Results describe the relationship between carbon‐specific growth rate (μ C ) and chl a :carbon (chl a :C) and glutamine:glutamate (gln:glu) ratios with changes in the cells' nutritional status (N:C), during the utilization of either NO 3 − or NH 4 + . The use of the gln:glu ratio as an index of N:C requires further clarification. For both species and N sources, N stress resulted in a decrease in μ C , chl a :C, and N:C relative to μ Cmax values, whereas C stress resulted in a decrease in μ C and an increase in chl a :C and N:C relative to μ Cmax values. Both species attained a chl a :C ratio of approximately 15 μg·g − 1 at μ Cmax using either N source. However, this value was not necessarily an indicator of maximal growth rate. NC colimitation resulted in decreased μ C to values less than 20% of μ Cmax with only minor changes in chl a :C and N:C relative to μ Cmax values. Chl a :C results suggest a similarity between the light stress and C stress responses of marine diatoms. The potential for C stress in the marine environment needs to be addressed.