Further Measurements of Primary Production Using a Large‐volume Plastic Sphere

Abstract

The experiment described by McAllister, & (II. ( 1961)) in which a phytoplankton bloom was induced to occur in a free-floating 20-ft diameter thin transparent plastic sphere has been repeated. Daily measurements were made of nutrients, particulate matter, and photosynthetic rates with less frequent assays for vitamins and dissolved organic matter. In situ light was recorded by a bolometcr.The experiment was prolonged to 100 days to study phytoplankton decay, most of this period being in the dark. The phytoplankton consisted mainly of 6 species of diatom and one large dinoflagellate. The mean composition of this crop at various stages of its development is reported by ratios involving chlorophyll a and particulate organic carbon. A detailed discussion is given of the findings of the experiment which, in general, confirmed those of the carlicr work and yielded, in addition, valuable new information.The plant cells excreted 35-4OoJo of their organic matter during growth. The CI~ method of measuring photosynthesis gave results ngreeing well with the production of particulate carbon.The growth kinetics of the bloom were dominated by the constancy of the mean cell division rates which were relatively independent of temperature and light.

Phytoplankton and bacterial alkaline phosphatase activity in the northern Adriatic Sea

“…BA was converted to carbon content by a 142 conversion factor of 20 fg C/cell (Lee and Fuhrman, 1987) and CBA by a factor of 250 fg 143 C/cell (Kana and Gilbert, 1987). Phytoplankton C content was obtained by converting chl a 144 using a factor of 50 µg C/µg chl a (Antia et al, 1963) …”

Assimilatory sulfur metabolism in marine microorganisms

“…-7- Standing crop measurements assay the amount of a characteristic material which may be related to microbial biomass. Analyses of such parameters as particulate organic carbon (POC), particulate organic ,nitrogen (PON), protein, DNA, and carbohydrate are often performed in conjuction with photosynthesis measurements (Antia et al, 1963;Strickland et al, 1969) but are rarely used in field studies of bacterial distribution and growth (but see Hobbie et aL., 1972). An underlying assumption in this type of analysis is that only microorganisms are sampled and subsequently trapped on a filter.…”

Fluctuations in the Organic Carbon to Chlorophyll a Ratios for Estuarine Benthic Diatom Populations

“…Harvey (1953), Brown and Richardson (1968), Beale and Appleman (1971) and Sheridan (1972) found an inverse proportion between light intensity and chlorophyll a concentrations for algal cells. Steele and Baird (1962), Antia et al (1963), Coombs et al (1967), Eppley (1968), Strickland et al (1969), Hobson and Pariser (1971), Thomas and Dodson (1972) and Peny (1976) showed that deficiency of P, N and Si could lead to a considerable increase in the organic carbon to chlorophyll a ratios. Caperon and Meyer (1972), Eppley and Renger (1974) and Perry (1976) described a negative correlation between specific growth rate and the organic carbon to chlorophyll a ratio.…”

“…Parsons & Strickland (1959) 39.6 Antia et al (1963) 25 Eppley (1968) 22.2-47.5 Eppley et al (1971) 60 Eppley et al (1977) 10-90 Antia et al (1963) 23.5-114 Induced bloom; mixture of 6 diatoms and 1 dinoflagellate Coombs et al (1967) 23.5-29.6 Si-deficiency; Navicula pelliculosa phytoplankton Eppley (1968) (22.2-47.5)-No detectable N;natural population, (71.4-125.0) open sea, composition unknown StricMand et al (1969) 34.5-83.3 N limitation; deep tank population of Caclonia niei Hobson & Pariser (1971) 14.7-100.0 NO, deficiency; Thalassiosira fluviatilis Caperon & Meyer (1972) 55.0-500.0 N limitation; chemostat culture of nalassiosira pseudonana Thomas & Dodson (1972) 19.0-61.8 N limitation; chemostat culture of Chaetoceras gracilis Eppley & Renger (1974) N and P limitation; chemostat culture (1976) 28.6-91.4 of 72alassiosira pseudonana chlorophyll a ratios also hold for benthic diatom population~. Therefore, organic carbon to chlorophyll a ratios were determined for intertidal mobile benthic diatom populations.…”