The Redfield Ratio and Phytoplankton Growth Rate

1985 ◽  
Vol 65 (2) ◽  
pp. 487-504 ◽  
Author(s):  
P. Tett ◽  
M. R. Droop ◽  
S. I. Heaney
Keyword(s):  
Growth Rate ◽  
Chemical Composition ◽  
Surface Waters ◽  
Growth Rates ◽  
Phytoplankton Growth ◽  
Maximal Growth ◽  
Redfield Ratio ◽  
Phytoplankton Growth Rate ◽  
Marine Surface ◽  
Natural Phytoplankton

Goldman, McCarthy & Peavey (1979b) argued that growth rates of phyto-plankton in apparently oligotrophic ocean waters may near maximal. Their hypothesis was succinctly restated by Goldman (1980): ‘…the chemical composition of phytoplankton is extremely variable under exacting laboratory conditions of nutrient limitation and approaches the ‘Redfield’ proportions (C:N:P of 106:16:1) when neither nitrogen nor phosphorus is limiting so that near maximal growth rates are attained. In marine surface waters the chemical composition of particular matter often is in the Redfield proportions, thus implying that natural phytoplankton growth rates may be close to maximal.’ We argue on theoretical, experimental and observational grounds that this implication may not necessarily be correct.

A modeling approach to simulate impact of climate change in lake water quality: phytoplankton growth rate assessment

1998 ◽  
Vol 37 (2) ◽  
pp. 177-185 ◽  
Author(s):  
Hany Hassan ◽  
Keisuke Hanaki ◽  
Tomonori Matsuo
Keyword(s):  
Climate Change ◽  
Water Quality ◽  
Growth Rate ◽  
Dissolved Oxygen ◽  
Lake Water ◽  
Phytoplankton Growth ◽  
Quality Data ◽  
Model Parameters ◽  
Lake Water Quality ◽  
Phytoplankton Growth Rate

Global climate change induced by increased concentrations of greenhouse gases (especially CO2) is expected to include changes in precipitation, wind speed, incoming solar radiation, and air temperature. These major climate variables directly influence water quality in lakes by altering changes in flow and water temperature balance. High concentration of nutrient enrichment and expected variability of climate can lead to periodic phytoplankton blooms and an alteration of the neutral trophic balance. As a result, dissolved oxygen levels, with low concentrations, can fluctuate widely and algal productivity may reach critical levels. In this work, we will present: 1) recent results of GCMs climate scenarios downscaling project that was held at the University of Derby, UK.; 2) current/future comparative results of a new mathematical lake eutrophication model (LEM) in which output of phytoplankton growth rate and dissolved oxygen will be presented for Suwa lake in Japan as a case study. The model parameters were calibrated for the period of 1973–1983 and validated for the period of 1983–1993. Meterologic, hydrologic, and lake water quality data of 1990 were selected for the assessment analysis. Statistical relationships between seven daily meteorological time series and three airflow indices were used as a means for downscaling daily outputs of Hadley Centre Climate Model (HadCM2SUL) to the station sub-grid scale.

Zinc marine biogeochemistry in seawater: a review

2012 ◽  
Vol 63 (7) ◽  
pp. 644 ◽  
Author(s):  
Marie Sinoir ◽  
Edward C. V. Butler ◽  
Andrew R. Bowie ◽  
Mathieu Mongin ◽  
Pavel N. Nesterenko ◽  
...  
Keyword(s):  
Surface Waters ◽  
Phytoplankton Community ◽  
Conceptual Models ◽  
Biogeochemical Cycles ◽  
Phytoplankton Growth ◽  
Laboratory Studies ◽  
Marine Systems ◽  
Subtle Effect ◽  
Marine Biogeochemistry ◽  
Marine Surface

The interest in trace element biogeochemistry has arisen from the well demonstrated iron hypothesis that revealed the central role that iron exerts on oceanic primary and associated biogeochemical cycles. The essentiality of zinc for key biological enzymes, coupled with a nutrient-like vertical distribution with low dissolved concentrations in many marine surface waters, provided motivation to study zinc in marine systems. Laboratory studies have confirmed the importance of zinc to sustain phytoplankton growth and its influence on the composition of the phytoplankton community. However, mixed results were obtained in the field, which suggest a more subtle effect of zinc on oceanic phytoplankton growth than iron. As a consequence, consensus on its biological role, mechanisms at play or regional versus global relevance is currently lacking and highlights the need for new conceptual models of zinc in marine systems. The recent GEOTRACES program is generating new data approaches to discuss and understand further zinc behaviour in the ocean.

Phytoplankton growth rate and zooplankton grazing in the western part of the Black Sea in the autumn period

Oceanology ◽  
2009 ◽  
Vol 49 (1) ◽  
pp. 83-92 ◽  
Author(s):  
L. V. Stel’makh ◽  
I. I. Babich ◽  
S. Tugrul ◽  
S. Moncheva ◽  
K. Stefanova
Keyword(s):  
Growth Rate ◽  
Black Sea ◽  
Phytoplankton Growth ◽  
The Black Sea ◽  
Zooplankton Grazing ◽  
Autumn Period ◽  
Phytoplankton Growth Rate

scholarly journals Paleoclimate reconstruction in the Levant region from the petrography and the geochemistry of a MIS 5 stalagmite from the Kanaan Cave, Lebanon

2015 ◽  
Vol 11 (4) ◽  
pp. 3241-3275 ◽  
Author(s):  
C. Nehme ◽  
S. Verheyden ◽  
S. R. Noble ◽  
A. R. Farrant ◽  
J. J. Delannoy ◽  
...  
Keyword(s):  
Growth Rate ◽  
Isotopic Composition ◽  
Northern Hemisphere ◽  
Surface Waters ◽  
Growth Rates ◽  
Eastern Mediterranean ◽  
Last Interglacial ◽  
Paleoclimate Reconstruction ◽  
Isotopic Records ◽  
Mis 5

Abstract. Lying at the transition between the temperate Mediterranean domain and subtropical deserts, the Levant is a key area to study the palaeoclimatic response over glacial-interglacial cycles. This paper presents a precisely dated last interglacial (MIS 5) stalagmite (129–84 ka) from the Kanaan Cave, Lebanon. Variations in growth rate and isotopic records indicate a warm humid phase at the onst of the last interglacial at ~129 ka that lasted until ~125 ka. A gradual shift in speleothem isotopic composition (125–122 ka) is driven mainly by the δ18O source effect of the Eastern Mediterranean surface waters during Sapropel S5. The onset of glacial inception began after ~122 ka, interrupted by a short wet pulse during Sapropel S4. Low growth rates and enriched oxygen and carbon values until ~84 ka indicate a transition to drier conditions during Northern Hemisphere glaciation.

An early spring bloom of large diatoms in the ice-covered Saroma-ko Lagoon, Hokkaido, Japan

2011 ◽  
Vol 92 (1) ◽  
pp. 29-37 ◽  
Author(s):  
Akihiro Shiomoto ◽  
Koji Asakuma ◽  
Han-Dong Hoon ◽  
Koichi Sakaguchi ◽  
Kimihiko Maekawa
Keyword(s):  
Growth Rate ◽  
Global Warming ◽  
Primary Production ◽  
Spring Bloom ◽  
Early Spring ◽  
Phytoplankton Growth ◽  
Bloom Period ◽  
Ice Coverage ◽  
Phytoplankton Growth Rate ◽  
Free Area

Saroma-ko Lagoon, the largest body of water that has complete ice coverage during winter in Japan, was not completely covered by ice in the winter of 2009. This condition is considered to be a result of the progression of global warming. A bloom of large diatoms was observed in the ice-free area between February and April. This early spring bloom seemed to have started in the latter part of January, and lasted for about three months. The maximum chlorophyll-a (Chl a) concentration of about 10 mg m−3 was observed in March, and was similar to the level of 5–20 mg m−3 previously reported for the ordinary spring bloom in Saroma-ko Lagoon. The maximum primary production of 786 mgC m−2 day−1 and the maximum Chl a-specific primary production, an index of the phytoplankton growth rate, were also found in March. Species changes from Thalassiosira spp. to Chaetoceros spp. were observed during the bloom. This early spring bloom could extend into the ordinary spring bloom period. Its duration was obviously longer than that of the spring bloom, which is typically about one month. These results show the phytoplankton condition that could be expected during winter and spring as global warming progresses.

Dominance of phosphorus over nitrogen as the limiter to phytoplankton growth rate

Hydrobiologia ◽  
1978 ◽  
Vol 57 (3) ◽  
pp. 209-215 ◽  
Author(s):  
E. B. Welch ◽  
P. Sturtevant ◽  
M. A. Perkins
Keyword(s):  
Growth Rate ◽  
Phytoplankton Growth ◽  
Phytoplankton Growth Rate

scholarly journals Effect of temperature on the unimodal size scaling of phytoplankton growth

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Cristina Fernández-González ◽  
Emilio Marañón
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Standing Stock ◽  
Phytoplankton Growth ◽  
Effect Of Temperature ◽  
Intermediate Cell ◽  
Optimal Temperature ◽  
Response Curves ◽  
Size Scaling ◽  
Independent Field

AbstractContrary to predictions by the allometric theory, there is evidence that phytoplankton growth rates peak at intermediate cell sizes. However, it is still unknown if this pattern may result from the effect of experimental temperature. Here we test whether temperature affects the unimodal size scaling pattern of phytoplankton growth by (1) growing Synechococcus sp., Ostreococcus tauri, Micromonas commoda and Pavlova lutheri at 18 °C and 25 °C, and (2) using thermal response curves available in the literature to estimate the growth rate at 25 °C as well as the maximum growth rate at optimal temperature for 22 species assayed previously at 18 °C. We also assess the sensitivity of growth rate estimates to the metric employed for measuring standing stocks, by calculating growth rates based on in vivo fluorescence, chlorophyll a concentration, cell abundance and biomass (particulate organic carbon and nitrogen content). Our results show that the unimodal size scaling pattern of phytoplankton growth, with a peak at intermediate cell sizes, is observed at 18 °C, 25 °C and at the optimal temperature for growth, and that it prevails irrespective of the standing-stock metric used. The unimodal size scaling pattern of phytoplankton growth is supported by two independent field observations reported in the literature: (i) a positive relationship between cell size and metabolic rate in the picophytoplankton size range and (ii) the dominance of intermediate-size cells in nutrient-rich waters during blooms.

scholarly journals Disparities between <i>Phaeocystis</i> in situ and optically-derived carbon biomass and growth rates: potential effect on remote-sensing primary production estimates

2014 ◽  
Vol 11 (4) ◽  
pp. 6119-6149
Author(s):  
L. Peperzak ◽  
H. J. van der Woerd ◽  
K. R. Timmermans
Keyword(s):  
Growth Rate ◽  
Quantum Efficiency ◽  
Growth Rates ◽  
Standing Stock ◽  
Phytoplankton Growth ◽  
Ex Situ ◽  
Fluorescent Light ◽  
Limited Growth ◽  
Global Carbon

Abstract. The oceans play a pivotal role in the global carbon cycle. Unfortunately, the daily production of organic carbon, the product of phytoplankton standing stock and growth rate cannot be measured globally by discrete oceanographic methods. Instead, optical proxies from Earth-orbiting satellites must be used. To test the accuracy of optically-derived proxies of phytoplankton physiology and growth rate, standard ex situ data from the wax and wane of a Phaeocystis bloom in laboratory mesocosms were compared with hyperspectral reflectance data. Chlorophyll biomass could be estimated accurately from reflectance using specific chlorophyll absorption algorithms. However, the conversion of chlorophyll (Chl) to carbon (C) was obscured by the observed increase in C : Chl under nutrient-limited growth. C : Chl was inversely correlated (r2 = 0.88) with Photosystem II quantum efficiency (Fv/Fm), the in situ fluorometric oceanographic proxy for growth rate. In addition, the optical proxy for growth rate, the quantum efficiency of fluorescence &amp;varphi; was linearly correlated to Fv/Fm (r2 = 0.84), but not – as by definition – by using total phytoplankton absorption, because during nutrient-limited growth the concentrations of non-fluorescent light-absorbing pigments increased. As a consequence, none of the three proxies (C : Chl, Fv/Fm, φ) was correlated to carbon or cellular phytoplankton growth rates. Therefore, it is concluded that although satellite derived estimates of chlorophyll biomass may be accurate, physiologically-induced non-linear shifts in growth rate proxies may obscure accurate phytoplankton growth rates and hence global carbon production estimates.

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