Growth of the spinose planktonic foraminifer Orbulina universa in laboratory culture and the effect of temperature on life processes

1987 ◽  
Vol 67 (2) ◽  
pp. 343-358 ◽  
Author(s):  
David A. Caron ◽  
Walter W. Faber ◽  
Allan W. H. Bé
Keyword(s):  
Surface Waters ◽  
Planktonic Foraminifera ◽  
World Ocean ◽  
Laboratory Culture ◽  
Effect Of Temperature ◽  
Growth Stages ◽  
Additional Source ◽  
Planktonic Foraminifer ◽  
Transition Zones ◽  
Orbulina Universa

Orbulina universa d'Orbigny is a spinose planktonic foraminifer which occurs throughout surface waters of the tropical, subtropical and transition zones of the world ocean (Bé & Tolderlund, 1971). This species is unique among planktonic Foraminifera in that its life cycle is composed of two growth stages. The juvenile stage is a trochospiral form which is enclosed within a terminal spherical chamber in the adult stage. O. universa is relatively omnivorous, and consumes a variety of prey that range in size and quality from phytoplankton to copepods (Bé et al. 1977; Anderson et al. 1979; Spindler et al. 1984). In addition, each individual harbors several thousand zooxanthellae which presumably are an additional source of nutrition for the foraminifer (Be et al. 1977; Hemleben & Spindler, 1983; Spero & Parker, 1985).

The Effect of Temperature and Food Concentration On Ingestion Rates of Quinqueloculina Seminula On the Diatom Nitzschia Closterium

2019 ◽  
Vol 49 (1) ◽  
pp. 3-10 ◽  
Author(s):  
Yanli Lei ◽  
Chengchun Li ◽  
Tiegang Li ◽  
Zhimin Jian
Keyword(s):  
Food Availability ◽  
Ingestion Rate ◽  
Food Concentration ◽  
Laboratory Culture ◽  
Effect Of Temperature ◽  
Clearance Rates ◽  
Organic Detritus ◽  
Local Conditions ◽  
Ingestion Rates ◽  
Nitzschia Closterium

Abstract The majority of sediment-dwelling foraminifera are thought to be deposit feeders. They use their reticulopodia to gather sediment with associated algae, organic detritus, and bacteria. Uptake of diatoms by foraminifera have been observed but rarely quantified. We measured the clearance (gathering) rate and ingestion rate of diatoms by the common benthic foraminifer Quinqueloculina seminula using Nitzschia closterium as prey under laboratory culture conditions. Grazing experiments were performed to evaluate the effects of temperature (at 12, 15, 18, 21, and 24°C) and food availability (10 to 800 cells mm−2) on uptake rates of diatoms. The clearance rates, estimated from the disappearance of food items, were variable (0.59–4.4 mm2 foram−1 h−1) and did not show a clear relationship with food availability. The maximum clearance rates increased from 1.80 ± 0.21 to 2.69 ± 0.32 mm2 foram−1 h−1 when temperature increased from 12 to 18°C and decreased to 2.28 ± 0.25 mm2 foram−1 h−1 at 24°C. Ingestion rates varied from 1.0 to 43 × 103 diatoms foram−1 h−1, following a hyperbolic response to food concentrations at all experimental temperatures. The maximum individual ingestion rates increased from 842 ± 180 to 1648 ± 480 (mean ± SE) cells foram−1 h−1 and then decreased to 316 ± 54 cells foram−1 h−1 as temperature increased from 12 to 24°C. Experimental results revealed that 12–18°C was the optimal temperature range for Q. seminula feeding for specimens adapted to local conditions. Our study indicates that Q. seminula plays an ecological role by feeding upon benthic diatoms in marine benthic ecosystems.

Assessing the Global Meltwater Spike

1982 ◽  
Vol 17 (2) ◽  
pp. 148-172 ◽  
Author(s):  
Glenn A. Jones ◽  
William F. Ruddiman
Keyword(s):  
Deep Sea ◽  
Planktonic Foraminifera ◽  
World Ocean ◽  
Equatorial Atlantic ◽  
Low Salinity ◽  
Ice Volume ◽  
Middle Latitudes ◽  
Mixing Intensity ◽  
Entire World ◽  
Isotopic Signal

AbstractL. V. Worthington (1968, Meteorological Monographs 8, 63–67) hypothesized that a low-salinity lid covered the entire world ocean. By deconvolving isotopic curves from the western equatorial Pacific and equatorial Atlantic, W. H. Berger, R. F. Johnson, and J. S. Killingley (1977), Nature (London) 269, 661–663) and W. H. Berger (1978, Deep-Sea Research 25, 473–480) reconstructed “meltwater spikes” similar to those actually observed in the Gulf of Mexico and thus apparently confirmed the Worthington hypothesis. It is shown that this conclusion is unwarranted. The primary flaw in the reconstructed meltwater spikes is that the mixing intensity used in the deconvolution operation is overestimated. As a result, structure recorded in the mixed isotopic record becomes exaggerated in the attempt to restore the original unmixed record. This structure can be attributed to variable ice-volume decay during deglaciation, effects of differential solution on planktonic foraminifera, temporal changes in abundance of the foraminifera carrying the isotopic signal, and analytical error. An alternative geographic view to the global low-salinity lid is offered: a map showing portions of the ocean potentially affected by increased deglacial meltwater at middle and high latitudes and by increased precipitation-induced runoff at low and middle latitudes.

scholarly journals Insights into the Cenozoic geology of North Beirut (harbour area): biostratigraphy, sedimentology and structural history

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Germaine Noujaim Clark ◽  
Marcelle Boudagher-Fadel
Keyword(s):  
Planktonic Foraminifera ◽  
Foraminiferal Assemblage ◽  
Early Pliocene ◽  
North East ◽  
The North ◽  
Rock Structure ◽  
Structural History ◽  
Orbulina Universa ◽  
Geological Complexity ◽  
Harbour Area

The biostratigraphy and sedimentology of the outcrops and bedrock recently exposed in archaeological excavations around the harbour area of Beirut (~5 km²) unlock the geological and structural history of that area, which in turn are key to understanding the hydrocarbon and hydrogeological potential of the region. A key location (Site 2) of a studied outcrop section and newly uncovered bedrock is on the northern foothill cliff of East Beirut (Achrafieh). The outcrop section of carbonates is of Eocene beds overlain by conformable Miocene beds. The excavation of the slope bordering the outcrop uncovered a bedrock section of an early Pliocene shoreline of carbonate/siliciclastic sands at its base and topped by a beach-rock structure. The early Pliocene age of the shoreline section is dated by an assemblage of planktonic foraminifera that includes Sphaeroidinellopsis subdehiscens , Sphaeroidinella dehiscens and Orbulina universa . The Eocene carbonates of Site 2 extend the coverage of the previously reported Eocene outcrops in the harbour area. They form a parasequence of thin-bedded, chalky white limestones that includes the youngest fossil fish deposits in Lebanon ( Bregmaceros filamentosus ). The deposits are dated as early Priabonian by their association with the planktonic foraminiferal assemblage of Porticulasphaera tropicalis , Globigerinatheka barri , Dentoglobigerina venezuelana , Globigerina praebulloides , Turborotalia centralis and Borelis sp. The Middle Miocene carbonates that conformably overlie the early Priabonian, parasequence include a planktonic foraminiferal assemblage of Globigerinoides trilobus , Orbulina universa and Borelis melo . Elsewhere, in the harbour area, the preserved Eocene limestones are also overlain by conformable Miocene carbonate parasequences of Langhian–Serravallian age. Younger argillaceous limestone beds of the Mio/Pliocene age occur in the eastern central part of the harbour area and enclose an assemblage of Truncorotalia crassaformis , Globorotalia inflata and Orbulina universa . The three markers of old and recently raised structural blocks in the harbour area are a Lutetian/Bartonian marine terrace in the south west corner, a lower Pliocene shoreline carbonate section in the north east side and a Holocene raised beach of marine conglomerates in the north east corner of the area. The locations of these paleo-shorelines, less than 2 km apart, indicate a progressive platform narrowing of North Beirut since the Paleogene. This study underpins the geological complexity of the region and contributes to understanding the underlying geology, which will be needed for future regional archaeological, hydrocarbon and hydrogeological exploration.

Effects of feeding frequency on life processes of the planktonic foraminifer Globigerinoides sacculifer in laboratory culture

1981 ◽  
Vol 61 (1) ◽  
pp. 257-277 ◽  
Author(s):  
A. W. H. Bé ◽  
D. A. Caron ◽  
O. R. Anderson
Keyword(s):  
Survival Time ◽  
Survival Data ◽  
Inverse Correlation ◽  
Laboratory Culture ◽  
Control Group ◽  
Feeding Frequency ◽  
Planktonic Foraminifer ◽  
Shell Size ◽  
Average Survival ◽  
Feeding Regimes

Globigerinoides sacculifer (Brady), a common planktonic foraminifer collected by SCUBA off Barbados, was maintained under six feeding regimes at constant light and temperature conditions. Five groups of 63 specimens each were fed 1-day-old Anemia at the rate of one nauplius per specimen every 1, 2, 3, 4 or 7 days. A starved control group received no Anemia. The rate of chamber formation and shell size increased proportional to the feeding frequency. However, an inverse correlation existed between survival time and feeding frequency. Normally, survival time ends with gametogenesis which terminates the life of the mother cell. Organisms fed more frequently reached maturity and underwent gametogenesis more rapidly than those fed less frequently. The average survival time of G. sacculifer in culture ranged from 7 days for the daily-fed group to 11 days for the group fed every 7 days. While the latter grew more slowly they eventually reached maturity. Starved individuals rarely formed chambers and often died without undergoing gametogenesis. Symbiotic zooxanthellae presumably prolonged survival of starved organisms. Extrapolation of survival data suggests G. sacculifer has a variable life span of 2 to 4 weeks depending on food availability.

Air Oxygen Calibration of Oxygen Optodes on a Profiling Float Array

2015 ◽  
Vol 32 (11) ◽  
pp. 2160-2172 ◽  
Author(s):  
Kenneth S. Johnson ◽  
Joshua N. Plant ◽  
Stephen C. Riser ◽  
Denis Gilbert
Keyword(s):  
Surface Waters ◽  
Atmospheric Oxygen ◽  
World Ocean ◽  
Sensor Calibration ◽  
Profiling Float ◽  
Sensor Drift ◽  
Oxygen Measurement ◽  
The Difference ◽  
World Ocean Atlas ◽  
One Year

AbstractAanderaa optode sensors for dissolved oxygen show remarkable stability when deployed on profiling floats, but these sensors suffer from poor calibration because of an apparent drift during storage (storage drift). It has been suggested that measurement of oxygen in air, during the period when a profiling float is on the surface, can be used to improve sensor calibration and to determine the magnitude of sensor drift while deployed in the ocean. The effect of air calibration on oxygen measurement quality with 47 profiling floats that were equipped with Aanderaa oxygen optode sensors is assessed. Recalibrated oxygen concentration measurements were compared to Winkler oxygen titrations that were made at the float deployment stations and to the World Ocean Atlas 2009 oxygen climatology. Recalibration of the sensor using air oxygen reduces the sensor error, defined as the difference from Winkler oxygen titrations in the mixed layer near the time of deployment, by about tenfold when compared to errors obtained with the factory calibration. The relative error of recalibrated sensors is <1% in surface waters. A total of 29 floats were deployed for time periods in excess of one year in ice-free waters. Linear changes in the percent of atmospheric oxygen reported by the sensor, relative to the oxygen partial pressure expected from the NCEP air pressure, range from −0.9% to +1.3% yr−1 with a mean of 0.2% ± 0.5% yr−1. Given that storage drift for optode sensors is only negative, it is concluded that there is no evidence for sensor drift after they are deployed and that other processes are responsible for the linear changes.

scholarly journals The Effect of Temperature on Seed Germination and Seedling Growth of Two Invasive Plants in Rorippa

2020 ◽  
pp. 39-48
Author(s):  
Qiuli Wang ◽  
Bo Qu ◽  
Juanjuan Mi ◽  
Yufeng Xu ◽  
Meini Shao
Keyword(s):  
Seed Germination ◽  
Invasive Plants ◽  
Seedling Growth ◽  
Petri Dish ◽  
Germination Percentage ◽  
Laboratory Culture ◽  
Liaoning Province ◽  
Effect Of Temperature ◽  
Invasion Mechanism ◽  
Root Shoot Ratio

Aims: By studying the response of seed germination and seedling growth of invasive plants, Rorippa amphibia and Rorippa sylvestris, to temperature, the influence of temperature on the invasive ability of two species of Rorippa were further analyzed, which provided a theoretical basis for revealing the diffusion and invasion mechanism of two invasive plants in Rorippa. Study Design: Seed germination and seedling growth test of two invasive plants in Rorippa at different temperature was studied by means of laboratory culture. The germination percentage, germination index, germination potential of the seeds and the total leaf number, root length, lateral root number, biomass and root shoot ratio of seedlings were determined. Place and Duration of Study: Seeds were collected from the Shenyang Agricultural University of Liaoning Province in July 2018. Experiments were done in the College of Bioscience and Biotechnology, and conducted in April 2019 for a month. Methodology: The petri dish method was used at the experiment of seed germination. The seedling growth experiment was carried out by pot sowing. Results: At the seedling stage.R. amphibia has the strongest tolerance at 30°C, while the R. sylvestris does at 35°C. The low temperature is more beneficial to the accumulations of the seedlings, R. amphibia is the most tolerant at 25°C, and R. sylvestris is at 30°C at the seedling stage. Conclusion: The response of the seeds and seedlings of the two species to temperature was basically the same. Higher temperature promoted seed germination and inhibited seedling growth, while lower temperature inhibited seed germination. The response of seeds and seedlings of R. sylvestris to high temperature makes it more invasive in the process of global warming.

scholarly journals Modeling seasonal and vertical habitats of planktonic foraminifera on a global scale

2017 ◽  
Author(s):  
Kerstin Kretschmer ◽  
Lukas Jonkers ◽  
Michal Kucera ◽  
Michael Schulz
Keyword(s):  
Climate Change ◽  
Water Column ◽  
Planktonic Foraminifera ◽  
World Ocean ◽  
Warm Season ◽  
Cold Season ◽  
Vertical Dimension ◽  
Time Space ◽  
Species Specific ◽  
Water Species

Abstract. Species of planktonic foraminifera exhibit specific seasonal production patterns and different preferred vertical habitats. The seasonality and vertical habitats are not constant throughout the range of the species and changes therein must be considered when interpreting paleoceanographic reconstructions based on fossil foraminifera. Accounting for the effect of vertical and seasonal habitat tracking on foraminifera proxies at times of climate change is difficult because it requires independent fossil evidence. An alternative that could reduce the bias in paleoceanographic reconstructions is to predict species-specific habitat shifts under climate change using an ecosystem modeling approach. To this end, we present a new version of a planktonic foraminifera model, PLAFOM2.0, embedded into the ocean component of the Community Earth System Model, version 1.2.2. This model predicts monthly global concentrations of the planktonic foraminiferal species: Neogloboquadrina pachyderma, N. incompta, Globigerina bulloides, Globigerinoides ruber (white), and Trilobatus sacculifer throughout the world ocean, resolved in 24 vertical layers to 250 m depth. The resolution along the vertical dimension has been implemented by applying the previously used spatial parameterization of biomass as a function of temperature, light, nutrition, and competition on depth-resolved parameter fields. This approach alone results in the emergence of species-specific vertical habitats, which are spatially and temporally variable. Although an explicit parameterization of the vertical dimension has not been carried out, the seasonal and vertical distribution patterns predicted by the model are in good agreement with sediment trap data and plankton tow observations. In the simulation, the colder-water species N. pachyderma, N. incompta, and G. bulloides show a pronounced seasonal cycle in their depth habitat in the polar and subpolar regions, which appears to be controlled by food availability. During the warm season, these species preferably occur in the subsurface, while towards the cold season they ascend through the water column and are found closer to the sea surface. The warm-water species G. ruber (white) and T. sacculifer exhibit a less variable shallow depth habitat with highest biomass concentrations within the top 40 m of the water column. Nevertheless, even these species show vertical habitat variability and their seasonal occurrence outside the tropics is limited to the warm surface layer that develops at the end of the warm season. The emergence in PLAFOM2.0 of species-specific vertical habitats that are consistent with observations indicates that the population dynamics of planktonic foraminifera species may be driven by the same factors in time, space, and with depth, in which case the model can provide a reliable and robust tool to aid the interpretation of proxy records.

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