Seasonal Variations in the Biochemical Compositions of Phytoplankton and Transparent Exopolymer Particles (TEPs) at Jang Bogo Station (Terra Nova Bay, Ross Sea), 2017–2018

The biochemical composition of particulate organic matter (POM) mainly originates from phytoplankton. Transparent exopolymer particles (TEPs) depend on environmental conditions and play a role in the food web and biogeochemical cycle in marine ecosystems. However, little information on their characteristics in the Southern Ocean is available, particularly in winter. To investigate the seasonal characteristics of POM and TEPSs, seawater samples were collected once every two weeks from November 2017 to October 2018 at Jang Bogo Station (JBS) located on the coast of Terra Nova Bay in the Ross Sea. The total chlorophyll-a (Chl-a) concentrations increased from spring (0.08 ± 0.06 μg L−1) to summer (0.97 ± 0.95 μg L−1) with a highest Chl-a value of 2.15 μg L−1. After sea ice formation, Chl-a rapidly decreased in autumn (0.12 ± 0.10 μg L−1) and winter (0.01 ± 0.01 μg L−1). The low phytoplankton Chl-a measured in this study was related to a short ice-free period in summer. Strong seasonal variations were detected in the concentrations of proteins and lipids (one-way ANOVA test, p < 0.05), whereas no significant difference in carbohydrate concentrations was observed among different seasons (one-way ANOVA test, p > 0.05). The phytoplankton community was mostly composed of diatoms (88.8% ± 11.6%) with a large accumulation of lipids. During the summer, the POM primarily consisted of proteins. The composition being high in lipids and proteins and the high caloric content in summer indicated that the phytoplankton would make a good food source. In winter, the concentrations of proteins decreased sharply. In contrast, relatively stable concentrations of carbohydrates and lipids have been utilized for respiration and long-term energy storage in the survival of phytoplankton. The TEPS values were significantly correlated with variations in the biomass and species of the phytoplankton. Our study site was characterized by dominant diatoms and low Chl-a concentrations, which could have resulted in relatively low TEP concentrations compared to other areas. The average contributions of TEP-C to the total POC were relatively high in autumn (26.9% ± 6.1%), followed by those in summer (21.9% ± 7.1%), winter (13.0% ± 4.2%), and spring (9.8% ± 3.1%).

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Assessment of Annual Physico-Chemical Variability via High-Temporal Resolution Monitoring in an Antarctic Shallow Coastal Site (Terra Nova Bay, Ross Sea)

Minerals ◽

10.3390/min11040374 ◽

2021 ◽

Vol 11 (4) ◽

pp. 374

Author(s):

Chiara Lombardi ◽

Piotr Kuklinski ◽

Andrea Bordone ◽

Edoardo Spirandelli ◽

Giancarlo Raiteri

Keyword(s):

Ross Sea ◽

Biological Activities ◽

Total Alkalinity ◽

Carbon Dioxide Partial Pressure ◽

High Temporal Resolution ◽

Coastal Site ◽

Chl A ◽

Terra Nova Bay ◽

Physico Chemical ◽

Terra Nova

The Southern Ocean is an important atmospheric carbon sink, and potential changes in the carbon flux in this region will affect the ocean as a whole. Thus, to monitor the variability of its physico-chemical parameters is becoming a priority. This study provides the first high-resolution all-year-round record of observed and computed physico-chemical data from a shallow coastal site in Terra Nova Bay (Ross Sea). From November 2018 to November 2019, an underwater observatory deployed at a 25 m depth under an ice pack recorded pressure (p), temperature (t), electrical conductivity (C), dissolved oxygen (DO), pH in total scale (pHT), and illuminance (Ev). Practical salinity (SP), density (ρ), tidal constituents, carbonate system parameters (total alkalinity (TA), carbon dioxide partial pressure (pCO2), calcite, and aragonite (ΩCa, ΩAr)), together with sea ice concentration (SIC) and chlorophyll-a (Chl-a), were derived from measured and satellite data. t, DO, and pHT displayed the lowest values between July and November (–1.95 °C, 6.61 mL L−1, 7.97) whereas the highest in January (+1.08 °C, 10.61 mL L−1, 8.35). SP had the lowest values (33.72 PSU) in February and the highest (34.87 PSU) in September. Ev peaked in March (201 lux), with the highest values (>50 lux) in correspondence to the lowest values of SIC and a delayed trend, between December and March, with respect to Chl-a values (0.2–1.1 mg m−3). ΩCa and ΩAr showed their highest average monthly values (±s.d.) in January (ΩCa: 3.41 ± 0.27; ΩAr: 2.14 ± 0.17), when DO had maximum values. The lowest Ω occurred in September (ΩCa: 2.11 ± 0.02; ΩAr: 1.32 ± 0.02), at the end of phytoplankton activity. No undersaturation for both calcite and aragonite was recorded during the study period. This study highlights that biological activities and physico-chemical variables of the investigated shallow coastal site are coupled and, in many cases, influence each other.

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Particulate organic matter release below melting sea ice (Terra Nova Bay, Ross Sea, Antarctica): Possible relationships with zooplankton

Journal of Marine Systems ◽

10.1016/j.jmarsys.2021.103510 ◽

2021 ◽

pp. 103510

Author(s):

Alessandro Cau ◽

Claudia Ennas ◽

Davide Moccia ◽

Olga Mangoni ◽

Francesco Bolinesi ◽

...

Keyword(s):

Organic Matter ◽

Sea Ice ◽

Particulate Organic Matter ◽

Ross Sea ◽

Terra Nova Bay ◽

Terra Nova

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A comparison between polynya area and associated ice production with mooring-based measurements of temperature, salinity and currents in the southwestern Ross Sea, Antarctica

Annals of Glaciology ◽

10.3189/172756411795931705 ◽

2011 ◽

Vol 52 (57) ◽

pp. 291-300 ◽

Cited By ~ 3

Author(s):

Stefan Kern ◽

Stefano Aliani

Keyword(s):

Ross Sea ◽

Time Lag ◽

Ice Formation ◽

Terra Nova Bay ◽

In Situ Observations ◽

Satellite Microwave ◽

Terra Nova ◽

Ice Production ◽

The Impact

AbstractWintertime (April–September) area estimates of the Terra Nova Bay polynya (TNBP), Antarctica, based on satellite microwave radiometry are compared with in situ observations of water salinity, temperature and currents at a mooring in Terra Nova Bay in 1996 and 1997. In 1996, polynya area anomalies and associated anomalies in polynya ice production are significantly correlated with salinity anomalies at the mooring. Salinity anomalies lag area and/or ice production anomalies by about 3 days. Up to 50% of the variability in the salinity at the mooring position can be explained by area and/or ice production anomalies in the TNBP for April–September 1996. This value increases to about 70% when considering shorter periods like April–June or May–July, but reduces to 30% later, for example July–September, together with a slight increase in time lag. In 1997, correlations are smaller, less significant and occur at a different time lag. Analysis of ocean currents at the mooring suggests that in 1996 conditions were more favourable than in 1997 for observing the impact of descending plumes of salt-enriched water formed in the polynya during ice formation on the water masses at the mooring depth.

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Diesel oil and PCB-degrading psychrotrophic bacteria isolated from Antarctic seawaters (Terra Nova Bay, Ross Sea)

Polar Research ◽

10.3402/polar.v23i2.6275 ◽

2004 ◽

Vol 23 (2) ◽

pp. 141-146 ◽

Cited By ~ 9

Author(s):

Maria De Domenico ◽

Angelina Lo Giudice ◽

Luigi Michaud ◽

Marcello Saitta ◽

Vivia Bruni

Keyword(s):

Ross Sea ◽

Diesel Oil ◽

Psychrotrophic Bacteria ◽

Terra Nova Bay ◽

Terra Nova

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Summer Epiphytic Diatoms from Terra Nova Bay and Cape Evans (Ross Sea, Antarctica) - A Synthesis and Final Conclusions

PLoS ONE ◽

10.1371/journal.pone.0153254 ◽

2016 ◽

Vol 11 (4) ◽

pp. e0153254 ◽

Cited By ~ 15

Author(s):

Roksana Majewska ◽

Peter Convey ◽

Mario De Stefano

Keyword(s):

Ross Sea ◽

Epiphytic Diatoms ◽

Terra Nova Bay ◽

Terra Nova

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Significance of selected halocarbons monitoring in air samples collected in the Terra Nova Bay region (northern Victoria Land, Antarctica)

Antarctic Science ◽

10.1017/s0954102099000322 ◽

1999 ◽

Vol 11 (2) ◽

pp. 261-264 ◽

Cited By ~ 3

Author(s):

Filippo Mangani ◽

Michela Maione ◽

Luciano Lattanzi

Keyword(s):

Ross Sea ◽

Atmospheric Concentration ◽

Air Samples ◽

Terra Nova Bay ◽

Victoria Land ◽

Rate Of Increase ◽

Terra Nova ◽

Concentration Levels

CCl3F (or CFC-11) and CCl2F2 (or CFC-12) were determined in air samples collected, during subsequent summer Antarctic campaigns, in different sampling sites in the Ross Sea Region. The samples were analysed by GC-ECD after enrichment. Data obtained since 1988–89 were plotted to observe the trend of CFCs atmospheric concentration levels. A decrease in the rate of increase of CFC-12 concentration was observed, whilst the concentration of CFC-11 was actually seen to be decreasing.

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ANALISIS PERBANDINGAN KINERJA KEUANGAN BANK SYARIAH DI INDONESIA, MALAYSIA, BRUNEI DAN THAILAND PERIODE 2011-2016

Jurnal Ekonomi Syariah Teori dan Terapan ◽

10.20473/vol5iss201810pp835-847 ◽

2019 ◽

Vol 5 (10) ◽

pp. 835

Author(s):

Adyagunita Karini ◽

Dian Filianti

Keyword(s):

Financial Performance ◽

Capital Adequacy ◽

Anova Test ◽

Islamic Bank ◽

Brunei Darussalam ◽

Analysis Technique ◽

Capital Adequacy Ratio ◽

Significant Difference ◽

Standards And Regulations ◽

One Way Anova

Comparing the financial performance of banks with other countries would show if the different standards and regulations affect their performance. This research aims to know if there is a significant difference in financial performance of sharia banks between Indonesia, Malaysia, Brunei and Thailand during 2011-2016. The samples used in this research consist of one sharia bank from each country: Bank Syariah Mandiri, Maybank Islamic Berhad, Bank Islam Brunei Darussalam and Islamic Bank of Thailand. This research uses a comparative quantitativeapproach using Non Performing Financing (NPF), Financing to Deposit Ratio (FDR), Return on Asset (ROA), and Capital Adequacy Ratio (CAR) as variables to indicate financial performance. One-Way ANOVA is used as the analysis technique. Results of the ANOVA test show there is a significant difference in NPF, FDR, ROA and CAR between sharia banks in Indonesia, Malaysia, Brunei and Thaiand as indicated by a significance value of 0,000 and 0,002.

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