Mn / Ca intra-test variability in the benthic foraminifer Ammonia tepida

Abstract. The adaptation of some benthic foraminiferal species to low oxygen conditions provides the prospect of using the chemical composition of their tests as proxies for bottom water oxygenation. Manganese may be particularly suitable as such a geochemical proxy, because this redox element is soluble in reduced form (Mn2+), and hence can be incorporated into benthic foraminiferal tests under low oxygen conditions. Therefore, intra- and inter-test differences in foraminiferal Mn / Ca ratios may hold important information about short term variability in pore water Mn2+ concentrations and sediment redox conditions. Here, we studied Mn / Ca inter- and intra-test variability of living individuals of the shallow infaunal foraminifer Ammonia tepida sampled in Lake Grevelingen (The Netherlands) in three different months of 2012. The deeper parts of this lake are characterised by seasonal hypoxia/anoxia with associated shifts in microbial activity and sediment geochemistry, leading to seasonal Mn2+ accumulation in the pore water. Earlier laboratory experiments with similar seawater Mn2+ concentrations as encountered in the pore waters of Lake Grevelingen suggest that intrinsic intra-test variability in A. tepida (11–25 % RSD) is responsible for a considerable portion of the observed variability in Mn / Ca. Our results show that the seasonally highly dynamic environmental conditions in the study area lead to a strongly increased Mn / Ca intra- and inter-test variability (average of 45 % RSD). Within single specimens, both increasing and decreasing trends in Mn / Ca ratios with size are observed. Our results suggest that the variability of successive single chamber Mn / Ca ratios reflects the temporal variability of pore water Mn2+. Additionally, active or passive migration of the foraminifera in the surface sediment may explain part of the observed Mn / Ca variability.

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Mn∕Ca intra- and inter-test variability in the benthic foraminifer Ammonia tepida

Biogeosciences ◽

10.5194/bg-15-331-2018 ◽

2018 ◽

Vol 15 (1) ◽

pp. 331-348 ◽

Cited By ~ 12

Author(s):

Jassin Petersen ◽

Christine Barras ◽

Antoine Bézos ◽

Carole La ◽

Lennart J. de Nooijer ◽

...

Keyword(s):

Pore Water ◽

Sediment Geochemistry ◽

Reduced Form ◽

Pore Waters ◽

Low Oxygen ◽

Oxygen Conditions ◽

Vital Effects ◽

Seasonal Hypoxia ◽

Test Variability ◽

Lake Grevelingen

Abstract. The adaptation of some benthic foraminiferal species to low-oxygen conditions provides the prospect of using the chemical composition of their tests as proxies for bottom water oxygenation. Manganese may be particularly suitable as such a geochemical proxy because this redox element is soluble in reduced form (Mn2+) and hence can be incorporated into benthic foraminiferal tests under low-oxygen conditions. Therefore, intra- and inter-test differences in foraminiferal Mn∕Ca ratios may hold important information about short-term variability in pore water Mn2+ concentrations and sediment redox conditions. Here, we studied Mn∕Ca intra- and inter-test variability in living individuals of the shallow infaunal foraminifer Ammonia tepida sampled in Lake Grevelingen (the Netherlands) in three different months of 2012. The deeper parts of this lake are characterized by seasonal hypoxia/anoxia with associated shifts in microbial activity and sediment geochemistry, leading to seasonal Mn2+ accumulation in the pore water. Earlier laboratory experiments with similar seawater Mn2+ concentrations as encountered in the pore waters of Lake Grevelingen suggest that intra-test variability due to ontogenetic trends (i.e. size-related effects) and/or other vital effects occurring during calcification in A. tepida (11–25 % relative SD, RSD) is responsible for part of the observed variability in Mn∕Ca. Our present results show that the seasonally highly dynamic environmental conditions in the study area lead to a strongly increased Mn∕Ca intra- and inter-test variability (average of 45 % RSD). Within single specimens, both increasing and decreasing trends in Mn∕Ca ratios with size are observed. Our results suggest that the variability in successive single-chamber Mn∕Ca ratios reflects the temporal variability in pore water Mn2+. Additionally, active or passive migration of the foraminifera in the surface sediment may explain part of the observed Mn∕Ca variability.

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Correlation of Virgulinella fragilis Grindell & Collen (benthic foraminiferid) with near-anoxia in Aso-kai Lagoon, central Japan

Journal of Micropalaeontology ◽

10.1144/jm.24.2.159 ◽

2005 ◽

Vol 24 (2) ◽

pp. 159-167 ◽

Cited By ~ 9

Author(s):

Hiroyuki Takata ◽

Koji Seto ◽

Saburo Sakai ◽

Satoshi Tanaka ◽

Katsumi Takayasu

Keyword(s):

Cluster Analysis ◽

Pore Water ◽

Coastal Lagoon ◽

Bottom Water ◽

Low Oxygen ◽

Central Japan ◽

Reactive Iron ◽

Predominant Species ◽

Oxygen Conditions ◽

Cluster A

Abstract. The distribution of Virgulinella fragilis and the hydro-environment of Aso-kai Lagoon, central Japan, were studied to clarify the foraminifer’s adaptation to low-oxygen conditions. The hypolimnion of the lagoon is oxygen-poor during much of the year. Two faunas (A and B) are recognized, based on cluster analysis. Cluster A fauna consists of species common in brackish lagoons, such as the genera Trochammina and Ammonia, and occurs in seasonally oxygenated waters. Virgulinella fragilis, the predominant species of Cluster B fauna, dominates the central part of the lagoon. This species can tolerate more severe oxygen deficiencies than the typical brackish foraminifers (e.g. Trochammina spp.) and can adapt to long periods of oxygen-poor conditions in coastal lagoon environments, as well as in pelagic to hemi-pelagic settings. In order to survive in the near-anoxia of Aso-kai Lagoon, V. fragilis may have adapted to environments in which little reactive iron is available in the sediment, leaving pore-water and bottom-water sulphide available for symbionts, or may utilize sulphur denitrification processes.

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Species Composition and Distribution of Jellyfish in a Seasonally Hypoxic Estuary, Hood Canal, Washington

Diversity ◽

10.3390/d12020053 ◽

2020 ◽

Vol 12 (2) ◽

pp. 53

Author(s):

BethElLee Herrmann ◽

Julie E. Keister

Keyword(s):

Dissolved Oxygen ◽

Low Oxygen ◽

Marine Food Webs ◽

Hood Canal ◽

The North ◽

Vertical Distributions ◽

Northern Regions ◽

Oxygen Conditions ◽

Seasonal Hypoxia ◽

Species Composition And Distribution

Seasonal hypoxia (≤2 mg dissolved oxygen L−1) can have detrimental effects on marine food webs. Recent studies indicate that some jellyfish can tolerate low oxygen and may have a competitive advantage over other zooplankton and fishes in those environments. We assessed community structure and distributions of cnidarian and ctenophore jellyfish in seasonally hypoxic Hood Canal, WA, USA, at four stations that differed in oxygen conditions. Jellyfish were collected in June through October 2012 and 2013 using full-water-column and discrete-depth net tows, concurrent with CTD casts to measure dissolved oxygen (DO). Overall, southern, more hypoxic, regions of Hood Canal had higher abundances and higher diversity than the northern regions, particularly during the warmer and more hypoxic year of 2013. Of fifteen species identified, the most abundant—the siphonophore Muggiaea atlantica and hydrozoan Aglantha digitale—reached peak densities > 1800 Ind m−3 and 38 Ind m−3, respectively. M. atlantica were much more abundant at the hypoxic stations, whereas A. digitale were also common in the north. Vertical distributions explored during hypoxia showed that jellyfish were mostly in the upper 10 m regardless of the oxycline depth. Moderate hypoxia seemed to have no detrimental effect on jellyfish in Hood Canal, and may have resulted in high population densities, which could influence essential fisheries and trophic energy flow.

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Faculty Opinions recommendation of The impact of increased oxygen conditions on metal-contaminated sediments part I: effects on redox status, sediment geochemistry and metal bioavailability.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.713998063.789502821 ◽

2012 ◽

Author(s):

Robyn Hannigan

Keyword(s):

Redox Status ◽

Contaminated Sediments ◽

Sediment Geochemistry ◽

Metal Bioavailability ◽

Oxygen Conditions ◽

The Impact

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The Production of hydrogen Sulphide and the Effects of Nitric Oxide (NO) and Low Oxygen Conditions in Intrauterine Tissues in Rats

Bulletin of Egyptian Society for Physiological Sciences ◽

10.21608/besps.2009.36719 ◽

2009 ◽

Vol 29 (2) ◽

pp. 195-206

Author(s):

Saad El-Sekelly ◽

Mohamed Mahmoud ◽

Morsy Matar

Keyword(s):

Nitric Oxide ◽

Hydrogen Sulphide ◽

Low Oxygen ◽

Production Of Hydrogen ◽

Oxygen Conditions

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Hydrochemistry of sediment pore water in the Bratsk reservoir (Baikal region, Russia)

Scientific Reports ◽

10.1038/s41598-021-90603-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

V. I. Poletaeva ◽

E. N. Tirskikh ◽

M. V. Pastukhov

Keyword(s):

Pore Water ◽

Ionic Composition ◽

Water System ◽

Water Reservoir ◽

Environmental Parameters ◽

Water Area ◽

Pore Waters ◽

Overlying Water ◽

Major Ion ◽

Bratsk Reservoir

AbstractThis study aimed to identify the factors responsible for the major ion composition of pore water from the bottom sediments of the Bratsk water reservoir, which is part of the largest freshwater Baikal-Angara water system. In the Bratsk reservoir, the overlying water was characterized as HCO3–Ca–Mg type with the mineralization ranging between 101.2 and 127.7 mg L−1 and pore water was characterized as HCO3–SO4–Ca, SO4–Cl–Ca–Mg and mixed water types, which had mineralization varying from 165.9 to 4608.1 mg L−1. The ionic composition of pore waters varied both along the sediment depth profile and across the water area. In pore water, the difference between the highest and lowest values was remarkably large: 5.1 times for K+, 13 times for Mg2+, 16 times for HCO3−, 20 times for Ca2+, 23 times for Na+, 80 times for SO42−, 105 times for Cl−. Such variability at different sites of the reservoir was due to the interrelation between major ion concentrations in the pore water and environmental parameters. The major factor responsible for pore water chemistry was the dissolution of sediment-forming material coming from various geochemical provinces. In the south part of the reservoir, Cl−, Na+ and SO42− concentrations may significantly increase in pore water due to the effect of subaqueous flow of highly mineralized groundwater.

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Identification and Functional Analysis of ThADH1 and ThADH4 Genes Involved in Tolerance to Waterlogging Stress in Taxodium hybrid ‘Zhongshanshan 406’

Genes ◽

10.3390/genes12020225 ◽

2021 ◽

Vol 12 (2) ◽

pp. 225

Author(s):

Lei Xuan ◽

Jianfeng Hua ◽

Fan Zhang ◽

Zhiquan Wang ◽

Xiaoxiao Pei ◽

...

Keyword(s):

Ethanol Metabolism ◽

Flooding Tolerance ◽

Transcriptome Data ◽

Low Oxygen ◽

Anaerobic Conditions ◽

Waterlogging Tolerance ◽

Waterlogging Stress ◽

Adh Genes ◽

Oxygen Conditions ◽

Stems And Leaves

The Taxodium hybrid ‘Zhongshanshan 406’ (T. hybrid ‘Zhongshanshan 406’) [Taxodium mucronatum Tenore × Taxodium distichum (L.). Rich] has an outstanding advantage in flooding tolerance and thus has been widely used in wetland afforestation in China. Alcohol dehydrogenase genes (ADHs) played key roles in ethanol metabolism to maintain energy supply for plants in low-oxygen conditions. Two ADH genes were isolated and characterized—ThADH1 and ThADH4 (GenBank ID: AWL83216 and AWL83217—basing on the transcriptome data of T. hybrid ‘Zhongshanshan 406’ grown under waterlogging stress. Then the functions of these two genes were investigated through transient expression and overexpression. The results showed that the ThADH1 and ThADH4 proteins both fall under ADH III subfamily. ThADH1 was localized in the cytoplasm and nucleus, whereas ThADH4 was only localized in the cytoplasm. The expression of the two genes was stimulated by waterlogging and the expression level in roots was significantly higher than those in stems and leaves. The respective overexpression of ThADH1 and ThADH4 in Populus caused the opposite phenotype, while waterlogging tolerance of the two transgenic Populus significantly improved. Collectively, these results indicated that genes ThADH1 and ThADH4 were involved in the tolerance and adaptation to anaerobic conditions in T. hybrid ‘Zhongshanshan 406’.

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