Plankton Production Biology

Phytoplankton samples, collected in 1953 and 1954 by the Calanus expeditions, were examined by the quantitative sedimentation method in an attempt to determine the ecological aspects of phytoplankton production in Hudson Bay and Strait. During the period July to September of both years, water temperature data, and salinity, oxygen and quantitative phytoplankton samples were collected at the surface and from depths of 10, 25, 50 and 100 metres. Numerically, the most abundant, heterogeneous phytoplankton populations were found in the mouth of Hudson Bay. The lower production of phytoplankton in the surface layer can be explained by the greater amplitude of temperature and salinity, dependent upon ice conditions and surface wind drift. The most productive layer was at a depth of 10 m. Large phytoplankton populations in waters supersaturated with oxygen were still found at 25 m, indicating light conditions favourable for photosynthesis. The relatively high plankton production in the area joining Hudson Bay and Hudson Strait is probably due to the hydrographic structure and the supply of nutrients resulting from the mixing of water masses which originate in other geographical areas. The preponderance of diatoms over flagellated groups, which is more marked in Hudson Strait than in Hudson Bay, is typical for the arctic. The composition of phytoplankton in these areas shows a great similarity in the main to that found on both sides of the Atlantic. Apart from locally produced plankton populations, there is a population exchange which follows water movements. To supplement the meagreness of existing taxonomic descriptions, attention is here focussed on the identification of plankters and their individual importance in the general ecology of the phytoplankton.

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Zoospore Production Biology of Pythiaceous Plant Pathogens

Journal of Phytopathology ◽

10.1111/jph.12154 ◽

2013 ◽

Vol 162 (2) ◽

pp. 69-80 ◽

Cited By ~ 3

Author(s):

Michael Pistininzi ◽

Edward Weiss ◽

Lauren Achtemeier ◽

Chuanxue Hong

Keyword(s):

Plant Pathogens ◽

Zoospore Production ◽

Production Biology

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Production biology of the upland bully Philypnodon breviceps Stokell in a small New Zealand lake. III. Production, food consumption and efficiency of food utilization

Journal of Fish Biology ◽

10.1111/j.1095-8649.1975.tb04575.x ◽

1975 ◽

Vol 7 (1) ◽

pp. 47-69 ◽

Cited By ~ 16

Author(s):

D. J. Staples

Keyword(s):

New Zealand ◽

Food Consumption ◽

Food Utilization ◽

Production Biology

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Distribution of paralarvae and small juvenile cephalopods in relation to primary production in an upwelling area off southern Brazil

ICES Journal of Marine Science ◽

10.1093/icesjms/fsq080 ◽

2010 ◽

Vol 67 (7) ◽

pp. 1346-1352 ◽

Cited By ~ 31

Author(s):

Erica A. G. Vidal ◽

Manuel Haimovici ◽

Vivian C. S. Hackbart

Keyword(s):

Primary Production ◽

Saline Water ◽

Southern Brazil ◽

Chl A ◽

Small Juvenile ◽

Tropical Water ◽

Brazil Current ◽

Plankton Production ◽

School Formation ◽

Upwelling Area

Abstract Vidal, E. A. G., Haimovici, M., and Hackbart, V. C. S. 2010. Distribution of paralarvae and small juvenile cephalopods in relation to primary production in an upwelling area off southern Brazil. – ICES Journal of Marine Science, 67: 1346–1352. The distribution of paralarvae and small juvenile cephalopods sampled by a rectangular midwater trawl (opening area 8 m2) over the continental shelf off Cape Santa Marta Grande, southern Brazil (28°09′S–29°56′S) during spring 1989 is discussed. An intrusion of Brazil Current Tropical Water (22°C; 36.5) separates warm, less-saline water (22°C; 35.2) from cooler, more-saline water (15°C; 36.4). Prevailing northeasterly winds led to upwelling of South Atlantic Central Water over the shelf, promoting high Chl a concentrations. Three species constituted 99% of the 628 cephalopods collected: Illex argentinus (n = 540; 4–40 mm mantle length, ML), Argonauta nodosa (n = 46; 2–19 mm ML), and Loligo sanpaulensis (n = 42, 2–21 mm ML). Segregation of I. argentinus juveniles of similar size suggests school formation as small as 10 mm ML. The presence of mature males along with fertilized female A. nodosa indicates mating early in life. There was a consistent and direct link between high plankton production and high densities of juvenile cephalopods through a short and ecologically efficient food chain. The relationship between production, pycnocline intensity, and the density of paralarvae and juveniles revealed suitable conditions for survival and growth during the upwelling season.

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