Early diagenesis in benthic foraminifera under anoxic conditions from the Landsort Deep, Baltic Sea (IODP Site M0063)

2020 ◽  
Author(s):  
Sha Ni ◽  
Nadine Quintana Krupinski ◽  
Jeroen Groeneveld ◽  
Karen Luise Knudsen ◽  
Per Persson ◽  
...  
Keyword(s):  
Baltic Sea ◽  
Trace Element ◽  
Environmental Conditions ◽  
Pore Waters ◽  
The Baltic Sea ◽  
Authigenic Carbonates ◽  
Anoxic Conditions ◽  
Diagenetic Alteration ◽  
Carbonate Formation ◽  
The Baltic

<p>The chemical composition of foraminiferal calcite is widely used for studying past environmental conditions and biogeochemistry. However, high rate of microbial-derived organic matter degradation and abundant dissolved metal sources in sediment and pore waters may impede the application of paleoenvironmental proxies due to formation of secondary carbonates on the outside and/or inside of foraminiferal tests. Secondary carbonate precipitation severely alters the foraminiferal geochemistry and can be difficult to eliminate through standard cleaning procedures for foraminiferal trace element analyses. Here we present results of the mineral composition and formation sequence of diagenetic coatings on the tests of foraminifera formed under extreme anoxic conditions in the Baltic Sea deepest basin (the Landsort Deep, IODP Exp. 347, Site M0063), as well as changing trace element concentrations of authigenic carbonates on the test on a millennial time-scale. The focus is on the diagenetic carbonates present on the tests of the low-oxygen tolerant benthic foraminiferal species <em>Elphidium selseyensis</em> and <em>Elphidium clavatum</em>. We applied geochemical and imaging methods by using scanning electron microscope imaging (SEM) and energy dispersive spectroscopy (EDS), synchrotron-based x-ray fluorescence microscopy (nano-XRF), RAMAN spectroscopy and laser ablation (LA)-ICP-MS, in order to ascertain the sedimentary diagenetic processes, and the foraminiferal authigenic mineral formation sequence. The authigenic carbonates were enriched in Mg, Mn, Fe and Ba, depending on the redox environmental conditions when the authigenic carbonates were precipitated. In particular, concentrations of redox-sensitive elements such as Mn and Fe were increased in bottom waters and sedimentary pore waters under oxygen-depleted conditions in the Landsort Deep, which resulted in Mn- and Fe-enriched carbonate formation. The diagenetic alteration on foraminiferal tests provides potential opportunity to investigate past sedimentary redox environment and primary productivity in the Baltic Sea.</p>

scholarly journals A three-dimensional view on biodiversity changes: spatial, temporal, and functional perspectives on fish communities in the Baltic Sea

2018 ◽  
Vol 75 (7) ◽  
pp. 2463-2475 ◽  
Author(s):  
Romain Frelat ◽  
Alessandro Orio ◽  
Michele Casini ◽  
Andreas Lehmann ◽  
Bastien Mérigot ◽  
...  
Keyword(s):  
Baltic Sea ◽  
Environmental Conditions ◽  
Environmental Changes ◽  
Temporal Dynamics ◽  
Marine Ecosystem ◽  
Fish Communities ◽  
The Baltic Sea ◽  
Functional Richness ◽  
Holistic Understanding ◽  
The Baltic

Abstract Fisheries and marine ecosystem-based management requires a holistic understanding of the dynamics of fish communities and their responses to changes in environmental conditions. Environmental conditions can simultaneously shape the spatial distribution and the temporal dynamics of a population, which together can trigger changes in the functional structure of communities. Here, we developed a comprehensive framework based on complementary multivariate statistical methodologies to simultaneously investigate the effects of environmental conditions on the spatial, temporal and functional dynamics of species assemblages. The framework is tested using survey data collected during more than 4000 fisheries hauls over the Baltic Sea between 2001 and 2016. The approach revealed the Baltic fish community to be structured into three sub-assemblages along a strong and temporally stable salinity gradient decreasing from West to the East. Additionally, we highlight a mismatch between species and functional richness associated with a lower functional redundancy in the Baltic Proper compared with other sub-areas, suggesting an ecosystem more susceptible to external pressures. Based on a large dataset of community data analysed in an innovative and comprehensive way, we could disentangle the effects of environmental changes on the structure of biotic communities—key information for the management and conservation of ecosystems.

Suboxic and Anoxic Conditions of Deep Waters in the Gdansk Basin of the Baltic Sea

Oceanology ◽  
2019 ◽  
Vol 59 (5) ◽  
pp. 639-647
Author(s):  
K. V. Artamonova ◽  
A. N. Demidov ◽  
O. A. Zuev
Keyword(s):  
Baltic Sea ◽  
The Baltic Sea ◽  
Anoxic Conditions ◽  
Deep Waters ◽  
The Baltic

Iron–manganese concretions contribute to benthic release of phosphorus and arsenic in anoxic conditions in the Baltic Sea

2016 ◽  
Vol 16 (8) ◽  
pp. 2138-2152 ◽  
Author(s):  
Pirjo Yli-Hemminki ◽  
Timo Sara-Aho ◽  
Kirsten S. Jørgensen ◽  
Jouni Lehtoranta
Keyword(s):  
Baltic Sea ◽  
The Baltic Sea ◽  
Anoxic Conditions ◽  
The Baltic ◽  
Iron Manganese

scholarly journals Local Environmental Conditions Shape Generalist But Not Specialist Components of Microbial Metacommunities in the Baltic Sea

2016 ◽  
Vol 07 ◽  
Author(s):  
Markus V. Lindh ◽  
Johanna Sjöstedt ◽  
Michele Casini ◽  
Agneta Andersson ◽  
Catherine Legrand ◽  
...  
Keyword(s):  
Baltic Sea ◽  
Environmental Conditions ◽  
The Baltic Sea ◽  
The Baltic

scholarly journals Distribution, abundance and environmental conditions of the clonal aquatic fern Salvinia natans (L.) All. in the Vistula delta (Baltic Sea Region)

2012 ◽  
Vol 28 (1) ◽  
pp. 45-53 ◽  
Author(s):  
Agnieszka Gałka ◽  
Józef Szmeja
Keyword(s):  
Baltic Sea ◽  
Environmental Conditions ◽  
Vistula Lagoon ◽  
Alkaline Ph ◽  
The Baltic Sea ◽  
Aquatic Fern ◽  
Baltic Sea Region ◽  
Salvinia Natans ◽  
The Baltic ◽  
Vistula Delta

Abstract We examined the distribution, resources and environmental conditions of the clonal aquatic fern Salvinia natans (L.) All., expansive in the Vistula delta (N Poland). Before 2006, there were 7 stands of this species, while in the years 2006-2010 their number increased to 21. The most abundant populations were found in the rivers: Tuga (133.0±37.6 indiv./0.1 m2), Fiszewka( 79.3±6.0), Szkarpawa (74.7±5.0), Struga Orłowska (61.0±2.0), Nogat (52.3±2.5), Elbląg (40.3±31.8), Wiślano-Zalewowy Canal (61.3±3.2) and in the SW part of Lake Druzno (72.3±2.5). S. natans did not colonise the weakly saline Vistula Lagoon and Elbląg Bay, which belong to the Baltic Sea. The plant under study occurred in shallow (2.2±1.5 m), narrow (17.9±13.6 m), slow-flowing (0.11±0.12 m s-1) and fertile (4.7±4.2 mg TN dm-3, 0.7±0.4 mg TP dm-3) watercourses. The water in them had neutral or alkaline pH (7.2-9.2) and was weakly saline (53.8±21.3 mg Cl dm-3). A dense mat of S. natans significantly affected the environmental conditions in the watercourses: water oxygenation, PAR intensity and concentration of biogenic substances, especially phosphorus, decreased.

scholarly journals Suboxic and anoxic conditions in the Gdansk basins’ deep water (the Baltic sea)

2019 ◽  
Vol 59 (5) ◽  
pp. 714-723
Author(s):  
K. V. Artamonova ◽  
A. N. Demidov ◽  
O. A. Zuev
Keyword(s):  
Dissolved Oxygen ◽  
Baltic Sea ◽  
Oxygen Concentration ◽  
Deep Water ◽  
Hydrogen Sulphide ◽  
Bottom Layer ◽  
Oxygen Distribution ◽  
The Baltic Sea ◽  
Anoxic Conditions ◽  
The Baltic

Variability of oxygen and hydrogen sulphide concentrations in the Gdansk basins deep water of the Baltic Sea for the last 25 years was analyzed. It was shown that suboxic and anoxic conditions in deep water were mainly determined by Baltic inflow frequency and intensity. Oxygen concentration in the bottom layer of the Gdansk basins increased strongly in 13 months after Major Baltic Inflow events (MBI). There were three periods of strong increasing of dissolve oxygen concentration in deep water since 1992 till 2018 after MBI in 1993, in 2003 and 20142016. It was shown that at the bottom of the Gdansk basins hydrogen sulphide was detected during 79 months till 22.5 years after MBI. Quality evaluation of dissolved oxygen distribution reanalysis was also conducted in this work. It can be noted good reproduction of field data by the reanalysis in its quality part; however, in most cases the observable maximum concentrations in dissolved oxygen distribution are understated, sometimes even several times.

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