scholarly journals Assessing proxy signatures of temperature, salinity, and hypoxia in the Baltic Sea through foraminifera-based geochemistry and faunal assemblages

2018 ◽  
Vol 37 (2) ◽  
pp. 403-429 ◽  
Author(s):  
Jeroen Groeneveld ◽  
Helena L. Filipsson ◽  
William E. N. Austin ◽  
Kate Darling ◽  
David McCarthy ◽  
...  
Keyword(s):  
Baltic Sea ◽  
Environmental Changes ◽  
Environmental Parameters ◽  
The Baltic Sea ◽  
Traditional Use ◽  
Geochemical Composition ◽  
Faunal Assemblages ◽  
The Past ◽  
Hypoxic Conditions ◽  
The Baltic

Abstract. Current climate and environmental changes strongly affect shallow marine and coastal areas like the Baltic Sea. This has created a need for a context to understand the severity and potential outcomes of such changes. The context can be derived from paleoenvironmental records during periods when comparable events happened in the past. In this study, we explore how varying bottom water conditions across a large hydrographic gradient in the Baltic Sea affect benthic foraminiferal faunal assemblages and the geochemical composition of their calcite tests. We have conducted both morphological and molecular analyses of the faunas and we evaluate how the chemical signatures of the bottom waters are recorded in the tests of several species of benthic foraminifera. We focus on two locations, one in the Kattegat (western Baltic Sea) and one in Hanö Bay (southern Baltic Sea). We show that seawater Mn∕Ca, Mg∕Ca, and Ba∕Ca (Mn∕Casw, Mg∕Casw, and Ba∕Casw) variations are mainly controlled by dissolved oxygen concentration and salinity. Their respective imprints on the foraminiferal calcite demonstrate the potential of Mn∕Ca as a proxy for hypoxic conditions, and Ba∕Ca as a proxy for salinity in enclosed basins such as the Baltic Sea. The traditional use of Mg∕Ca as a proxy to reconstruct past seawater temperatures is not recommended in the region, as it may be overprinted by the large variations in salinity (specifically on Bulimina marginata), Mg∕Casw, and possibly also the carbonate system. Salinity is the main factor controlling the faunal assemblages: a much more diverse fauna occurs in the higher-salinity (∼32) Kattegat than in the low-salinity (∼15) Hanö Bay. Molecular identification shows that only Elphidium clavatum occurs at both locations, but other genetic types of both genera Elphidium and Ammonia are restricted to either low- or high-salinity locations. The combination of foraminiferal geochemistry and environmental parameters demonstrates that in a highly variable setting like the Baltic Sea, it is possible to separate different environmental impacts on the foraminiferal assemblages and therefore use Mn∕Ca, Mg∕Ca, and Ba∕Ca to reconstruct how specific conditions may have varied in the past.

Stages of the Baltic Sea evolution in the geochemical record and radiocarbon dating of sediment cores from the Arkona Basin

2014 ◽  
Vol 43 (3) ◽  
Author(s):  
Robert Kostecki
Keyword(s):  
Baltic Sea ◽  
Environmental Changes ◽  
Sediment Cores ◽  
Late Glacial ◽  
Sudden Increase ◽  
The Baltic Sea ◽  
Geochemical Composition ◽  
Arkona Basin ◽  
The Baltic ◽  
Ancylus Lake

AbstractFour sediment cores from the southern part of the Arkona Basin were analyzed in terms of their geochemical composition, age and stratigraphy. The main stages of the Baltic Sea: the Baltic Ice Lake, the Ancylus Lake and the Littorina Sea were identified in all the analyzed cores. The data confirmed the high water fluctuation and significant environmental changes during the Baltic Sea evolution in the Late-Glacial and the Holocene. The signs of the second regression of the Baltic Ice Lake, dated at around 11 000 cal BP, were identified at a depth of 24 m b.s.l. Regression of the Ancylus Lake, dated at 9300 cal BP, was identified at a depth of 23 m b.s.l. The most pronounced period was the transition stage between the Ancylus Lake and the Littorina Sea. The record of the Littorina Sea onset in the sediments of the Arkona Basin is marked as a sudden increase in loss on ignition, biogenic silica, magnesium, calcium, iron and strontium. The age of the Littorina Sea in the Arkona Basin was estimated as younger than 8200 cal BP.

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.

Whitefish (Coregonus lavaretus (L.)) landings in the Baltic Sea during the past 100 years: combining official datasets and grey literature

2013 ◽  
Vol 64 ◽  
pp. 133-152 ◽  
Author(s):  
Aare Verliin ◽  
Lauri Saks ◽  
Roland Svirgsden ◽  
Markus Vetemaa ◽  
Mehis Rohtla ◽  
...  
Keyword(s):  
Baltic Sea ◽  
Grey Literature ◽  
Coregonus Lavaretus ◽  
The Baltic Sea ◽  
The Past ◽  
The Baltic

Screening the East, Probing the Past: The Baltic Sea in Contemporary German Cinema

2004 ◽  
Vol 22 (2) ◽  
pp. 27-48
Author(s):  
Alexandra Ludewig
Keyword(s):  
Gender Roles ◽  
Baltic Sea ◽  
Breeding Ground ◽  
Berlin Wall ◽  
The Baltic Sea ◽  
The Past ◽  
Traditional Gender Roles ◽  
German Cinema ◽  
The Baltic ◽  
Artistic Heritage

Since the fall of the Berlin Wall, unification, and the subsequent reinventionof the nation, German filmmakers have revisited theircountry’s cinematic traditions with a view to placing themselves creativelyin the tradition of its intellectual and artistic heritage. One ofthe legacies that has served as a point of a new departure has beenthe Heimatfilm, or homeland film. As a genre it is renowned for itsrestorative stance, as it often features dialect and the renunciation ofcurrent topicality, advocates traditional gender roles, has antimodernovertones of rural, pastoral, often alpine, images, and expressesa longing for premodern times, for “the good old days” that supposedlystill exist away from the urban centres. The Nazis used Heimatfilms in an effort “to idealize ‘Bauerntum’ as the site of desirable traditionsand stereotyped the foreign (most often the urban) as thebreeding ground for moral decay.”

Environmental factors affecting recent benthic foraminiferal distribution in the south-eastern Baltic Sea

Baltica ◽  
2020 ◽  
Vol 33 (1) ◽  
pp. 58-70
Author(s):  
Ekaterina Ponomarenko ◽  
Viktor Krechik ◽  
Evgenia Dorokhova
Keyword(s):  
Organic Carbon ◽  
Baltic Sea ◽  
Benthic Foraminifera ◽  
Bottom Water ◽  
Environmental Parameters ◽  
Organic Carbon Content ◽  
The South ◽  
The Baltic Sea ◽  
South Eastern ◽  
The Baltic

The Baltic Sea is characterized by a restricted exchange of deep waters due to permanent stratification of the water column. The aim of the present study is to investigate the distribution of benthic foraminifera in the south-eastern part of the Baltic Sea in relation to environmental parameters. The distribution of benthic foraminifera was analyzed in 26 surface sediment samples collected in the south-eastern part of the Baltic Sea and in the Bornholm Basin during springtime and wintertime 2016. Foraminiferal diversity in the studied region was extremely low. Agglutinated specimens dominated the assemblages and were represented by small-sized individuals which belong to Psammosphaera, Pseudothurammina, Saccammina, and Reophax genera. Calcareous foraminifera were dominated by Cribroelphidium genus. Micropaleontological data were compared to the environmental parameters characterizing bottom water (temperature, salinity, and dissolved oxygen content) and substrate conditions (grain size composition and total organic carbon content). Higher foraminiferal concentrations and diversity were found in deeper parts of the study region where fine-grained sediments with a higher total organic carbon content were accumulated under stable hydrographical conditions. Calcareous tests were found only at the stations with elevated salinity, indicating that bottom water salinity is the main factor limiting the distribution of calcareous foraminifera. On the other hand, substrate parameters and hydrodynamic conditions appear to play a major role in the distribution of agglutinated foraminifera.

Seasonal variability of phytoplankton in the shallow waters of the southern Baltic Sea

2018 ◽  
Vol 33 (1) ◽  
pp. 9-15
Author(s):  
Iwona Zabroś ◽  
Marlena Mioskowska
Keyword(s):  
Baltic Sea ◽  
Temporal Distribution ◽  
Environmental Parameters ◽  
Spatial And Temporal Variability ◽  
Sample Collection ◽  
The Baltic Sea ◽  
Mean Values ◽  
Southern Baltic Sea ◽  
Southern Baltic ◽  
The Baltic

The Baltic Sea is characterized by a seasonal variation of phytoplankton structure. These organisms are particularly sensitive to changes in various environmental parameters. Cyclic, recurring annually fluctuation of species composition, abundance and biomass of phytoplankton is a consequence of these changes. Spatial and temporal variability of particular groups of phytoplankton is not the same in different areas of the Baltic Sea. The purpose of this work was to determine the spatial and temporal distribution of phytoplankton in three chosen areas of the coastal zone of the southern Baltic Sea (Ustka, Poddąbie and Rowy) in the period of November 2014 - September 2016. Mean values of abundance and biomass of phytoplankton for the surveyed areas were typical for this type of coastal waters. In each of the surveyed areas the same dominat species in terms of the abundance and biomass were observed. A growth of diatoms was recorded only in the area of Ustka, which could have been caused by the inflow of river waters. Seasonal surveys of phytoplankton indicated that in the case of the studies regarding this parameter – taxonomic composition, abundance and biomass in the same surveyed area were similar at the three research stations (e.g. 75-80%), depending on the season of the year. On this basis, it was concluded that, whether carrying out the monitoring of phytoplankton or planned investments, the sample collection frequency had a greater significance than the number of research stations.

Regional differences in winter sea level variations in the Baltic Sea for the past 200 yr

2008 ◽  
Vol 60 (2) ◽  
pp. 384-393 ◽  
Author(s):  
Birgit Hünicke ◽  
Jürg Luterbacher ◽  
Andreas Pauling ◽  
Eduardo Zorita
Keyword(s):  
Baltic Sea ◽  
Sea Level ◽  
Regional Differences ◽  
The Baltic Sea ◽  
The Past ◽  
Sea Level Variations ◽  
The Baltic

scholarly journals Sedimentary alkalinity generation and long-term alkalinity development in the Baltic Sea

2018 ◽  
Author(s):  
Erik Gustafsson ◽  
Mathilde Hagens ◽  
Xiaole Sun ◽  
Daniel C. Reed ◽  
Christoph Humborg ◽  
...  
Keyword(s):  
Baltic Sea ◽  
Reactive Transport ◽  
Total Alkalinity ◽  
Biogeochemical Model ◽  
Co2 Uptake ◽  
Low Oxygen ◽  
The Baltic Sea ◽  
The Past ◽  
Oxygen Conditions ◽  
The Baltic

Abstract. Enhanced release of alkalinity from the seafloor, principally driven by anaerobic degradation of organic matter under low-oxygen conditions and associated secondary redox reactions, can increase the carbon dioxide (CO2) buffering capacity of seawater and therefore oceanic CO2 uptake. The Baltic Sea has undergone severe changes in oxygenation state and total alkalinity (TA) over the past decades. The link between these concurrent changes has not yet been investigated in detail. A recent system-wide TA budget constructed for the past 50 years using BALTSEM, a coupled physical-biogeochemical model for the whole Baltic Sea area, revealed an unknown TA source. Here we use BALTSEM in combination with observational data and one-dimensional reactive transport modelling of sedimentary processes in the Fårö Deep, a deep Baltic Sea basin, to test whether sulfate reduction coupled to iron (Fe) sulfide burial can explain the missing TA source in the Baltic Proper. We calculated that this burial can account for 26 % of the missing source in this basin, with the remaining TA possibly originating from unknown river inputs or submarine groundwater discharge. We also show that temporal variability in the input of Fe to the sediments since the 1970s drives changes in sulfur burial in the Fårö Deep, suggesting that Fe availability is the ultimate limiting factor for TA generation under anoxic conditions. The implementation of projected climate change and two nutrient load scenarios for the 21st century in BALTSEM shows that reducing nutrient loads will improve deep water oxygen conditions, but at the expense of lower surface water TA concentrations, CO2 buffering capacities and faster acidification. When these changes additionally lead to a decrease in Fe inputs to the sediment of the deep basins, anaerobic TA generation will be reduced even further, thus exacerbating acidification. This work highlights that Fe dynamics play a key role in the release of TA from sediments where Fe sulfide formation is limited by Fe availability, as exemplified for the Baltic Sea. Moreover, it demonstrates that burial of Fe sulfides should be included in TA budgets of low oxygen basins.

scholarly journals Sea Level Dynamics and Coastal Erosion in the Baltic Sea Region

2021 ◽  
Author(s):  
Ralf Weisse ◽  
Inga Dailidiene ◽  
Birgit Hünicke ◽  
Kimmo Kahma ◽  
Kristine Madsen ◽  
...  
Keyword(s):  
Baltic Sea ◽  
Sea Level ◽  
Coastal Erosion ◽  
Data Availability ◽  
The Baltic Sea ◽  
Mean Sea Level ◽  
The Past ◽  
Coastline Change ◽  
Baltic Sea Region ◽  
The Baltic

Abstract. There are a large number of geophysical processes affecting sea level dynamics and coastal erosion in the Baltic Sea region. These processes operate on a large range of spatial and temporal scales and are observed in many other coastal regions worldwide. Together with the outstanding number of long data records, this makes the Baltic Sea a unique laboratory for advancing our knowledge on interactions between processes steering sea level and erosion in a climate change context. Processes contributing to sea level dynamics and coastal erosion in the Baltic Sea include the still ongoing visco-elastic response of the Earth to the last deglaciation, contributions from global and North Atlantic mean sea level changes, or from wind waves affecting erosion and sediment transport along the subsiding southern Baltic Sea coast. Other examples are storm surges, seiches, or meteotsunamis contributing primarily to sea level extremes. All such processes have undergone considerable variations and changes in the past. For example, over the past about 50 years, the Baltic absolute (geocentric) mean sea level rose at a rate slightly larger than the global average. In the northern parts, due to vertical land movements, relative sea level decreased. Sea level extremes are strongly linked to variability and changes in the large-scale atmospheric circulation. Patterns and mechanisms contributing to erosion and accretion strongly depend on hydrodynamic conditions and their variability. For large parts of the sedimentary shores of the Baltic Sea, the wave climate and the angle at which the waves approach the nearshore are the dominant factors, and coastline changes are highly sensitive to even small variations in these driving forces. Consequently, processes contributing to Baltic sea level dynamics and coastline change are expected to vary and to change in the future leaving their imprint on future Baltic sea level and coastline change and variability. Because of the large number of contributing processes, their relevance for understanding global figures, and the outstanding data availability, we argue that global sea level research and research on coastline changes may greatly benefit from research undertaken in the Baltic Sea.

scholarly journals Sedimentary alkalinity generation and long-term alkalinity development in the Baltic Sea

2019 ◽  
Vol 16 (2) ◽  
pp. 437-456 ◽  
Author(s):  
Erik Gustafsson ◽  
Mathilde Hagens ◽  
Xiaole Sun ◽  
Daniel C. Reed ◽  
Christoph Humborg ◽  
...  
Keyword(s):  
Baltic Sea ◽  
Reactive Transport ◽  
Total Alkalinity ◽  
Biogeochemical Model ◽  
Co2 Uptake ◽  
Low Oxygen ◽  
The Baltic Sea ◽  
The Past ◽  
Oxygen Conditions ◽  
The Baltic

Abstract. Enhanced release of alkalinity from the seafloor, principally driven by anaerobic degradation of organic matter under low-oxygen conditions and associated secondary redox reactions, can increase the carbon dioxide (CO2) buffering capacity of seawater and therefore oceanic CO2 uptake. The Baltic Sea has undergone severe changes in oxygenation state and total alkalinity (TA) over the past decades. The link between these concurrent changes has not yet been investigated in detail. A recent system-wide TA budget constructed for the past 50 years using BALTSEM, a coupled physical–biogeochemical model for the whole Baltic Sea area revealed an unknown TA source. Here we use BALTSEM in combination with observational data and one-dimensional reactive-transport modeling of sedimentary processes in the Fårö Deep, a deep Baltic Sea basin, to test whether sulfate (SO42-) reduction coupled to iron (Fe) sulfide burial can explain the missing TA source in the Baltic Proper. We calculated that this burial can account for up to 26 % of the missing source in this basin, with the remaining TA possibly originating from unknown river inputs or submarine groundwater discharge. We also show that temporal variability in the input of Fe to the sediments since the 1970s drives changes in sulfur (S) burial in the Fårö Deep, suggesting that Fe availability is the ultimate limiting factor for TA generation under anoxic conditions. The implementation of projected climate change and two nutrient load scenarios for the 21st century in BALTSEM shows that reducing nutrient loads will improve deep water oxygen conditions, but at the expense of lower surface water TA concentrations, CO2 buffering capacities and faster acidification. When these changes additionally lead to a decrease in Fe inputs to the sediment of the deep basins, anaerobic TA generation will be reduced even further, thus exacerbating acidification. This work highlights that Fe dynamics plays a key role in the release of TA from sediments where Fe sulfide formation is limited by Fe availability, as exemplified by the Baltic Sea. Moreover, it demonstrates that burial of Fe sulfides should be included in TA budgets of low-oxygen basins.

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