Pigment Markers for Phytoplankton Production

Abstract Aim: There are few studies dealing with the biogeochemical processes occurring in small estuaries receiving high sewage loading in tropical regions. The aim of this investigation was to characterize the biogeochemical behavior of nutrients in superficial waters collected at the Iguaçu estuarine system, during specific conditions (neap tide), located at the inner sector of a heavily eutrophicated embayment (Guanabara Bay, SE Brazil). Methods Physical and chemical variables were measured in situ (pH, temperature, conductivity, salinity, total dissolved solids, transparency, dissolved oxygen), whereas suspended particulate matter, chlorophyll a, phaepigments and nutrients (carbon, nitrogen and phosphorus forms) were measured in laboratory across the mesohaline estuarine gradient. Results The Iguaçu River mouth is in a high stage of eutrophication, considering nutrient concentrations, chlorophyll a and transparency of water column. Results indicate a transition from heterotrophic conditions to autotrophic conditions, since the nutrients concentrations showed a decreasing pattern along the saline gradient, while the chlorophyll an increased over the transects. The pH values and chlorophyll : phaeopigments ratios are significantly related to the amount and quality of organic matter contents, especially at transects under strong marine influence. More than 95% of the dissolved and total nitrogen concentrations are represented by NH4+ contributions, which are related to the ammonification of organic matter contents in this region, indicating the existence of untreated sewage loads in this area. Conclusion In this study, the Iguaçu River seemed to contribute with high inputs of nutrients that support important phytoplankton production at the inner regions of the bay related to the CO2 sink and autotrophic metabolism, showing the importance of verifying the biogeochemical behaviors of nutrients in estuarine areas, even in small scale.

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Balance between Phytoplankton Production and Plankton Respiration in Lakes

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f93-032 ◽

1993 ◽

Vol 50 (2) ◽

pp. 282-289 ◽

Cited By ~ 79

Author(s):

Paul A. del Giorgio ◽

Robert H. Peters

Keyword(s):

Community Respiration ◽

Phytoplankton Production ◽

External Energy ◽

Eutrophic Lakes ◽

Oligotrophic Lakes ◽

Plankton Community Respiration ◽

Algal Photosynthesis ◽

Chlorophyll Concentrations ◽

Trophic Range ◽

Good Agreement

We analyzed published rates of algal photosynthesis and plankton community respiration to test the hypothesis that the ratio of planktonic primary production to community (P/R) varies systematically with lake trophy. Regression analyses show that algal production and plankton respiration are closely related to chlorophyll concentrations for lakes spanning a wide trophic range. More surprisingly, plankton respiration exceeds algal photosynthesis in oligotrophic lakes, and P/R rises above unity only when chlorophyll concentrations are above 17 mg∙m−3. A simple allometric model based on the predicted biomasses of the different planktonic component yield rates of community respiration that are in good agreement with measured values. Moreover, the model suggest that in oligotrophic lakes, microbial respiration may greatly exceed the current estimates based on bacterial production data and that heterotrophs contribute proportionately more to total plankton metabolism than they do in eutrophic lakes. Because such high respiration rates require external energy subsidies, these results; challenge the view that pelagial communities of most lakes are even approximately self-supporting.

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Phytoplankton of the Calanus Expeditions in Hudson Bay, 1953 and 1954

Journal of the Fisheries Research Board of Canada ◽

10.1139/f61-004 ◽

1961 ◽

Vol 18 (1) ◽

pp. 51-83 ◽

Cited By ~ 25

Author(s):

Adam Bursa

Keyword(s):

Surface Wind ◽

The Arctic ◽

Phytoplankton Production ◽

Hudson Bay ◽

Population Exchange ◽

Taxonomic Descriptions ◽

Hydrographic Structure ◽

Plankton Production ◽

Water Temperature Data ◽

Ice Conditions

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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Phytoplankton production and physiological adaptation on the southeastern shelf of the Agulhas ecosystem

Continental Shelf Research ◽

10.1016/j.csr.2010.05.007 ◽

2010 ◽

Vol 30 (13) ◽

pp. 1472-1486 ◽

Cited By ~ 28

Author(s):

R. Barlow ◽

T. Lamont ◽

M. Kyewalyanga ◽

H. Sessions ◽

T. Morris

Keyword(s):

Physiological Adaptation ◽

Phytoplankton Production

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Phytoplankton production in the Sargasso Sea as determined using optical mooring data

Journal of Geophysical Research Atmospheres ◽

10.1029/94jc00982 ◽

1994 ◽

Vol 99 (C9) ◽

pp. 18385 ◽

Cited By ~ 9

Author(s):

K. J. Waters ◽

R. C. Smith ◽

J. Marra

Keyword(s):

Phytoplankton Production ◽

Sargasso Sea

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Light, Nutrients, and Water Temperature as Determinants of Phytoplankton Production in Two Saline, Prairie Lakes with High Sulphate Concentrations

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f92-250 ◽

1992 ◽

Vol 49 (11) ◽

pp. 2281-2290 ◽

Cited By ~ 27

Author(s):

Richard D. Robarts ◽

Marlene S. Evans ◽

Michael T. Arts

Keyword(s):

Water Temperature ◽

Photosynthetic Capacity ◽

Chlorophyll Concentration ◽

Euphotic Zone ◽

Dominant Factor ◽

Phytoplankton Production ◽

Dissolved Phosphorus ◽

Prairie Lakes ◽

The Mean ◽

Algal Productivity

Our data support empirical models indicating that algal productivity is low relative to total phosphorus (TP) levels in prairie lakes with high sulphate concentrations. Mean chlorophyll accounted for 91.1% of the variance in euphotic zone primary production (ΣA) in Humboldt Lake (total dissolved solids (TDS) = 3.3 g∙L−1; Zmax = 6 m), while TP, total dissolved phosphorus, and water temperature accounted for 82.7% of ΣA variance in Redberry Lake (TDS = 20.9 g∙L−1; Zmax = 17 m). The relative importance of these variables to ΣA resulted from biological, chemical, and physical differences of these lakes. Light usually penetrated to the bottom of Redberry Lake due to a mean euphotic zone (Zeu) chlorophyll of 1.7 mg∙m−3, while Humboldt Lake's mean Zeu was 3.4 m with a mean chlorophyll concentration of 62.6 mg∙m−3. Chlorophyll was the dominant factor correlated with light penetration in Humboldt Lake (r2 = 0.65) but not in Redberry Lake. Photosynthetic capacity was correlated (r2 = 0.72) with water temperature only in Redberry Lake. The mean ΣA was 57.1 and 230.2 mg C∙m−2∙h−1 for Redberry and Humboldt lakes, respectively.

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