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Sample records for baltic sea traffic

  1. Pollution in the Baltic Sea.

    PubMed

    Rheinheimer, G

    1998-07-01

    The Baltic Sea is almost totally surrounded by land and therefore more endangered by pollution than other marine areas. The sources of marine pollution are municipal and industrial waste inputs directly into the sea or via rivers, and atmospheric inputs mainly from traffic and agriculture. The increase of inorganic plant nutrients (NH3, NOx, PO4) caused eutrophication and consequent oxygen depletion in coastal bottom waters as well as in the depths of the open sea. In the anoxic sediments, hydrogen sulfide can be produced by protein-decomposing and sulfate-reducing bacteria. The bottom fauna will be destroyed and only H2S tolerant microorganisms can survive. Originating from cellulose manufacturing and from paper mills, large amounts of poisonous chlorinated compounds contaminated the coastal waters of Sweden and Finland until the 1980s. Most of this material is still present in sediments of the central Baltic Sea and can be resuspended by near bottom currents. To reduce pollution and improve the situation in the Baltic Sea, the surrounding countries organized the Helsinki Convention, which came into force on 3.5.1980. The Helsinki Commission (HELCOM) founded in 1974 acts as coordinator and is responsible for the enforcement of the Baltic monitoring program and international research projects. The activities of HELCOM have led to the reduction of dangerous pollutants which in turn has caused the regeneration of flora and fauna in some areas. Further improvements can be expected. PMID:9722964

  2. A comprehensive inventory of the ship traffic exhaust emissions in the Baltic Sea from 2006 to 2009.

    PubMed

    Jalkanen, Jukka-Pekka; Johansson, Lasse; Kukkonen, Jaakko

    2014-04-01

    This study addresses the exhaust emissions of CO₂, NO(x), SO(x), CO, and PM(2.5) originated from Baltic Sea shipping in 2006-2009. Numerical results have been computed using the Ship Traffic Emissions Assessment Model. This model is based on the messages of the automatic identification system (AIS), which enable the positioning of ships with a high spatial resolution. The NO(x) emissions in 2009 were approximately 7 % higher than in 2006, despite the economic recession. However, the SO(x) emissions in 2009 were approximately 14 % lower, when compared to those in 2006, mainly caused by the fuel requirements of the SO(x) emission control area (SECA) which became effective in May 2006, but affected also by changes in ship activity. Results are presented on the differential geographic distribution of shipping emissions before (Jan-April 2006) and after (Jan-April 2009) the SECA regulations. The predicted NO(x) emissions in 2009 substantially exceeded the emissions in 2006 along major ship routes and at numerous harbors, mostly due to the continuous increase in the number of small vessels that use AIS transmitters. Although the SO(x) emissions have been reduced in 2009 in most major ship routes, these have increased in the vicinity of some harbors and on some densely trafficked routes. A seasonal variation of emissions is also presented, as well as the distribution of emissions in terms of vessel flag state, type, and weight.

  3. Curonian Spit, Baltic Sea

    NASA Technical Reports Server (NTRS)

    2006-01-01

    On July 25, 2006, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), flying on NASA's Terra satellite, captured this image of the Curonian (or Courland)spit, the Curonian Lagoon (also known as the Courland Lagoon) it encloses, and part of the Baltic Sea. Just 3,800 meters (about 12,460 feet) at its widest point, the spit encloses a lagoon of some 1,620 square kilometers (625 square miles). In this image, dark blue indicates deep water, and lighter blue indicates shallow and/or sediment-laden water. Different shades of blue distinguish the deeper Baltic Sea and the shallower Curonian Lagoon. Vegetation appears in varying shades of green, paved surfaces and bare ground appear in shades of beige and gray, and sandy areas appear off-white. Obvious sandy areas appear along the length of the spit. On the Baltic Sea side, a thin off-white band of beach runs the length of the spit; on the Curonian Lagoon side, intermittent beaches carve their way into the narrow strip of land.

  4. Baltic Earth - Earth System Science for the Baltic Sea Region

    NASA Astrophysics Data System (ADS)

    Meier, Markus; Rutgersson, Anna; Lehmann, Andreas; Reckermann, Marcus

    2014-05-01

    The Baltic Sea region, defined as its river catchment basin, spans different climate and population zones, from a temperate, highly populated, industrialized south with intensive agriculture to a boreal, rural north. It encompasses most of the Scandinavian Peninsula in the west; most of Finland and parts of Russia, Belarus, and the Baltic states in the east; and Poland and small parts of Germany and Denmark in the south. The region represents an old cultural landscape, and the Baltic Sea itself is among the most studied sea areas of the world. Baltic Earth is the new Earth system research network for the Baltic Sea region. It is the successor to BALTEX, which was terminated in June 2013 after 20 years and two successful phases. Baltic Earth stands for the vision to achieve an improved Earth system understanding of the Baltic Sea region. This means that the research disciplines of BALTEX continue to be relevant, i.e. atmospheric and climate sciences, hydrology, oceanography and biogeochemistry, but a more holistic view of the Earth system encompassing processes in the atmosphere, on land and in the sea as well as in the anthroposphere shall gain in importance in Baltic Earth. Specific grand research challenges have been formulated, representing interdisciplinary research questions to be tackled in the coming years. A major means will be scientific assessments of particular research topics by expert groups, similar to the BACC approach, which shall help to identify knowledge gaps and develop research strategies. Preliminary grand challenges and topics for which Working Groups have been installed include: • Salinity dynamics in the Baltic Sea • Land-Sea biogeochemical feedbacks in the Baltic Sea region • Natural hazards and extreme events in the Baltic Sea region • Understanding sea level dynamics in the Baltic Sea • Understanding regional variability of water and energy exchange • Utility of Regional Climate Models • Assessment of Scenario Simulations

  5. A multivariate Baltic Sea environmental index.

    PubMed

    Dippner, Joachim W; Kornilovs, Georgs; Junker, Karin

    2012-11-01

    Since 2001/2002, the correlation between North Atlantic Oscillation index and biological variables in the North Sea and Baltic Sea fails, which might be addressed to a global climate regime shift. To understand inter-annual and inter-decadal variability in environmental variables, a new multivariate index for the Baltic Sea is developed and presented here. The multivariate Baltic Sea Environmental (BSE) index is defined as the 1st principal component score of four z-transformed time series: the Arctic Oscillation index, the salinity between 120 and 200 m in the Gotland Sea, the integrated river runoff of all rivers draining into the Baltic Sea, and the relative vorticity of geostrophic wind over the Baltic Sea area. A statistical downscaling technique has been applied to project different climate indices to the sea surface temperature in the Gotland, to the Landsort gauge, and the sea ice extent. The new BSE index shows a better performance than all other climate indices and is equivalent to the Chen index for physical properties. An application of the new index to zooplankton time series from the central Baltic Sea (Latvian EEZ) shows an excellent skill in potential predictability of environmental time series.

  6. Status of Biodiversity in the Baltic Sea

    PubMed Central

    Ojaveer, Henn; Jaanus, Andres; MacKenzie, Brian R.; Martin, Georg; Olenin, Sergej; Radziejewska, Teresa; Telesh, Irena; Zettler, Michael L.; Zaiko, Anastasija

    2010-01-01

    The brackish Baltic Sea hosts species of various origins and environmental tolerances. These immigrated to the sea 10,000 to 15,000 years ago or have been introduced to the area over the relatively recent history of the system. The Baltic Sea has only one known endemic species. While information on some abiotic parameters extends back as long as five centuries and first quantitative snapshot data on biota (on exploited fish populations) originate generally from the same time, international coordination of research began in the early twentieth century. Continuous, annual Baltic Sea-wide long-term datasets on several organism groups (plankton, benthos, fish) are generally available since the mid-1950s. Based on a variety of available data sources (published papers, reports, grey literature, unpublished data), the Baltic Sea, incl. Kattegat, hosts altogether at least 6,065 species, including at least 1,700 phytoplankton, 442 phytobenthos, at least 1,199 zooplankton, at least 569 meiozoobenthos, 1,476 macrozoobenthos, at least 380 vertebrate parasites, about 200 fish, 3 seal, and 83 bird species. In general, but not in all organism groups, high sub-regional total species richness is associated with elevated salinity. Although in comparison with fully marine areas the Baltic Sea supports fewer species, several facets of the system's diversity remain underexplored to this day, such as micro-organisms, foraminiferans, meiobenthos and parasites. In the future, climate change and its interactions with multiple anthropogenic forcings are likely to have major impacts on the Baltic biodiversity. PMID:20824189

  7. Strontium-90 and cesium-137 distribution in Baltic Sea waters

    SciTech Connect

    Lazarev, L.N.; Gedeonov, L.I.; Ivanova, L.M.; Stepanov, A.V.

    1988-09-01

    The strontium-90 and cesium-137 concentrations determined in 1983 in the Baltic Sea proper and the Gulf of Finland and in the Soviet Baltic rivers are furnished. The cesium-137 content has been found to be directly proportional to the salinity of the water. Significant influx of technogenic radioactive contaminants from the North to the Baltic Sea was noted in 1983.

  8. Regime shifts in North Sea and Baltic Sea: A comparison

    NASA Astrophysics Data System (ADS)

    Dippner, Joachim W.; Möller, Caroline; Hänninen, Jari

    2012-12-01

    The ICES subdivisions in the North Sea (SD IIIa, SD IVa, and SD IVb) and the subdivisions in the Baltic Sea (SD 29, SD 27/28-2, and SD 25/26) are selected to compare the response in long term monitoring data (1970-2000) with respect to climate regime shifts. A modified AMOEBA model is applied to the data sets to identify the status and development of the North Sea and Baltic Sea system during two recent regime shifts. Biological regime shifts can be identified 1989/1990 in SD IIIa in the North Sea and in SD 25/26 in the Baltic Sea. A synchronous appearance of regime shifts could only be identified in the central and southern Baltic Sea for both regime shifts 1975/76 and 1989/90 where the AMOEBA model indicated a high similarity in ecosystem response. A clear difference was identified in the response of the North Sea and the Baltic Sea. Inter-annual and inter-decadal variability as well as regime shifts are driven in the Baltic Sea by direct atmospheric forcing only. In contrast, the changes in the North Sea are influenced by both the direct atmospheric forcing and the indirect forcing from the changes in North Atlantic. The fact that regime shifts as well as their synchronous appearance can be identified with the AMOEBA model might be of major interest for the management of sustainable use of ecosystem goods and services, the development of ecosystem approach to management and the implementation of the Marine Strategy Framework Directive (MSFD) of the European Union (EU).

  9. Changes in extreme sea levels in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Dieterich, Christian; Gröger, Matthias; Andersson, Helén; Nerheim, Signild; Jönsson, Anette

    2016-04-01

    A newly developed shallow water model for the Baltic Sea and North Sea is presented. The model is validated by means of a comparison with hindcast simulations with observational data sets. The aim of the development is to provide and apply a modelling tool to model extreme sea levels in the Baltic Sea, Kattegat and Skagerrak. The model approach will support the direct analysis of extreme sea level observations in the past and provide the possibility to extend the statistical data base by producing very long time series or very large ensembles of coastal sea levels. This effort is intended to contribute to an assessment of risks due to storm surges and coastal flooding in the 21st century along the coast of Sweden. By using different RCP climate scenarios downscaled with a regional, coupled climate model atmospheric forcing is available to project possible changes in extreme sea levels into the future. Projected sea level rise, changes in dynamical sea level in the North East Atlantic and tidal forcing in the northern North Sea are applied as boundary condition which allows to investigate their impact on the dynamics of regional sea level variability. Initial experiments focus on the impact of model resolution, resolution in the atmospheric forcing and the amount of details necessary in the bathymetry to faithfully model coastal sea level in the Baltic Sea and North Sea.

  10. The nutrient load from food waste generated onboard ships in the Baltic Sea.

    PubMed

    Wilewska-Bien, Magda; Granhag, Lena; Andersson, Karin

    2016-04-15

    The combination of the sensitive characteristics of the Baltic Sea and the intense maritime traffic makes the marine environment vulnerable to anthropogenic influences. The theoretical scenario calculated in this study shows that the annually generated food waste onboard ships in traffic in the Baltic Sea contains about 182tonnes of nitrogen and 34tonnes of phosphorus. Today, all food waste generated onboard can be legally discharged into the marine environment at a distance of 12NM from the nearest land. The annual load of nitrogen contained in the food waste corresponds to 52% of load of nitrogen from the ship-generated sewage. Future regulations for sewage discharge in the Baltic Sea will require significant reduction of total nitrogen and phosphorus released. The contribution of nutrients from food waste compared to sewage will therefore be relatively larger in the future, if food waste still can be legally discharged.

  11. The nutrient load from food waste generated onboard ships in the Baltic Sea.

    PubMed

    Wilewska-Bien, Magda; Granhag, Lena; Andersson, Karin

    2016-04-15

    The combination of the sensitive characteristics of the Baltic Sea and the intense maritime traffic makes the marine environment vulnerable to anthropogenic influences. The theoretical scenario calculated in this study shows that the annually generated food waste onboard ships in traffic in the Baltic Sea contains about 182tonnes of nitrogen and 34tonnes of phosphorus. Today, all food waste generated onboard can be legally discharged into the marine environment at a distance of 12NM from the nearest land. The annual load of nitrogen contained in the food waste corresponds to 52% of load of nitrogen from the ship-generated sewage. Future regulations for sewage discharge in the Baltic Sea will require significant reduction of total nitrogen and phosphorus released. The contribution of nutrients from food waste compared to sewage will therefore be relatively larger in the future, if food waste still can be legally discharged. PMID:26992746

  12. Biotope map of the German Baltic Sea.

    PubMed

    Schiele, Kerstin S; Darr, Alexander; Zettler, Michael L; Friedland, René; Tauber, Franz; von Weber, Mario; Voss, Joachim

    2015-07-15

    Full-coverage maps on the distribution of marine biotopes are a necessary basis for Nature Conservation and Marine Spatial Planning. Yet biotope maps do not exist in many regions. We are generating the first full-coverage biotope map for the German Baltic Sea according to the HELCOM Underwater biotope and habitat classification system (HUB). Species distribution modelling is applied to create full-coverage spatial information of biological features. The results of biomass modelling of twelve target taxa and presence/absence modelling of three target taxa enabled the identification of biological levels up to HUB level 6. Environmental data on bathymetry, light penetration depth and substrate are used to identify habitat levels. HUB biotope levels were combined with HUB habitat levels to create a biotope map. Altogether, 68 HUB biotopes are identified in the German Baltic Sea. The new biotope map combining substrate characteristics and biological communities will facilitate marine management in the area.

  13. Reduction of Baltic Sea nutrient inputs and allocation of abatement costs within the Baltic Sea catchment.

    PubMed

    Wulff, Fredrik; Humborg, Christoph; Andersen, Hans Estrup; Blicher-Mathiesen, Gitte; Czajkowski, Mikołaj; Elofsson, Katarina; Fonnesbech-Wulff, Anders; Hasler, Berit; Hong, Bongghi; Jansons, Viesturs; Mörth, Carl-Magnus; Smart, James C R; Smedberg, Erik; Stålnacke, Per; Swaney, Dennis P; Thodsen, Hans; Was, Adam; Zylicz, Tomasz

    2014-02-01

    The Baltic Sea Action Plan (BSAP) requires tools to simulate effects and costs of various nutrient abatement strategies. Hierarchically connected databases and models of the entire catchment have been created to allow decision makers to view scenarios via the decision support system NEST. Increased intensity in agriculture in transient countries would result in increased nutrient loads to the Baltic Sea, particularly from Poland, the Baltic States, and Russia. Nutrient retentions are high, which means that the nutrient reduction goals of 135 000 tons N and 15 000 tons P, as formulated in the BSAP from 2007, correspond to a reduction in nutrient loadings to watersheds by 675 000 tons N and 158 000 tons P. A cost-minimization model was used to allocate nutrient reductions to measures and countries where the costs for reducing loads are low. The minimum annual cost to meet BSAP basin targets is estimated to 4.7 billion Euro.

  14. Astaxanthin dynamics in Baltic Sea mesozooplankton communities

    NASA Astrophysics Data System (ADS)

    Snoeijs, Pauline; Häubner, Norbert

    2014-01-01

    The red pigment astaxanthin is a powerful antioxidant, which occurs in eggs and body tissues of crustaceans and fish. It is produced by crustaceans from algal carotenoids. In a two-year field study we assessed natural concentrations and dynamics of astaxanthin in mesozooplankton communities in the brackish Baltic Sea area. Astaxanthin levels varied between 0.37 and 36 ng L- 1. They increased with salinity along the Baltic Sea gradient and were linked to zooplankton biomass and phytoplankton community composition. Astaxanthin concentrations showed typical seasonal patterns and varied from 0.2 to 5.1 ng ind- 1, 0.2 to 3.4 ng (μg C)- 1 and 6 to 100 ng mm- 3. These concentrations were inversely related to water temperature and strongly linked to zooplankton community composition. Communities dominated by the calanoid copepods Temora longicornis, Pseudocalanus acuspes and Eurytemora spp. generally held the highest concentrations. With increasing cladocerans:copepods biomass ratios community astaxanthin concentrations decreased and with higher relative biomass of Acartia spp. the proportion of astaxanthin diesters decreased. Diesters prevailed in the cold season and they are thought to improve the antioxidant protection of storage lipids during winter. Climate change causes higher temperature and lower salinity in the Baltic Sea proper. This modifies zooplankton community composition, but not necessarily into a community with lower concentrations of astaxanthin since T. longicornis (high concentrations) has been reported to increase with higher temperature. However, decreased astaxanthin production in the ecosystem is expected if a basin-wide increase in the cladocerans:copepods biomass ratios would occur with further climate change.

  15. Sea Salt Source Function over the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Petelski, Tomasz; Makuch, Przemyslaw; Markuszewski, Piotr; Jankowski, Andrzej; Zieliński, Tymon

    2013-04-01

    Studies of production and transport of aerosol over the sea are very important for many areas of knowledge. Marine aerosol emitted from the sea surface helps to clean the boundary layer from other aerosol particles. The emitted droplets do not dry out in the highly humid surface layer air and because of their sizes most of them are deposited quickly at the sea surface. Therefore, marine aerosol has many features of rain i.e. the deposition in the marine boundary layer in high wind events is controlled not only by the "dry" processes but also by the "wet" scavenging. While many cruises conducted on board S/Y Oceania, we collected many data which were used to calculate sea salt source function over the Baltic Sea. Our cruises held between 2009 and 2012. Measurements were carried out using gradient method. For this method we used Laser Particle Counter (PMS model CSASP-100_HV) placed on one oft the mast of S/Y Oceania. Measurements were performed on five different levels around sea level: 8, 11, 14, 17 and 20 meters. Based on the averaged vertical concentration, profiles were calculated, using Monin-Obuchow theory, vertical sea spray fluxes in the near water layer. Based on fluxes calculated from vertical concentration profiles was calculated sea salt source function over the Baltic Sea. This function gives emission for different particle size, depending on environmental parameters. Emission of sea spray depends of the size of energy lost by the wind waves in process of collapse. Acknowledgements: The support for this study was provided by the project Satellite Monitoring of the Baltic Sea Environment - SatBałtyk founded by European Union through European Regional Development Fund contract No. POIG 01.01.02-22-011/09.

  16. Migration waves to the Baltic Sea region.

    PubMed

    Lappalainen, T; Laitinen, V; Salmela, E; Andersen, P; Huoponen, K; Savontaus, M-L; Lahermo, P

    2008-05-01

    In this study, the population history of the Baltic Sea region, known to be affected by a variety of migrations and genetic barriers, was analyzed using both mitochondrial DNA and Y-chromosomal data. Over 1200 samples from Finland, Sweden, Karelia, Estonia, Setoland, Latvia and Lithuania were genotyped for 18 Y-chromosomal biallelic polymorphisms and 9 STRs, in addition to analyzing 17 coding region polymorphisms and the HVS1 region from the mtDNA. It was shown that the populations surrounding the Baltic Sea are genetically similar, which suggests that it has been an important route not only for cultural transmission but also for population migration. However, many of the migrations affecting the area from Central Europe, the Volga-Ural region and from Slavic populations have had a quantitatively different impact on the populations, and, furthermore, the effects of genetic drift have increased the differences between populations especially in the north. The possible explanations for the high frequencies of several haplogroups with an origin in the Iberian refugia (H1, U5b, I1a) are also discussed. PMID:18294359

  17. Severity of sea ice in the Southern Baltic Sea, Gulf of Finland and Gulf of Bothnia up 21st century

    NASA Astrophysics Data System (ADS)

    Marzenna, Sztobryn

    2012-11-01

    The study focused on the evaluation of probable changes in the severity of sea ice conditions occurring in 3 selected areas of the Baltic Sea: the Gulf of Bothnia, Gulf of Finland and the Southern Baltic Sea up to the year 2100. The areas have been chosen due to the high intensity of marine traffic (the Gulfs—of Bothnia and of Finland) and due to differences in sea ice conditions; winters in the Gulf of Bothnia were characterized as the most severe, whereas in the Southern Baltic were classified as the mildest ones. Consequently, three scenarios were taken into account in the study: A2 (slow rate of global economic development, market scenario), A1B (regional scenario, rapid economic development, with ecological priorities), B1 (sustainable, median economic development with strong ecological priorities), all three constructed on the basis of Special Report on Emissions Scenarios (SRES models of greenhouse gas emission). The probable changes of sea ice conditions expressed as severity index S were calculated from these models. The main results of the investigation are as follows, the variety of sea ice conditions occurring in specific regions of the Baltic will remain stable (i.e. the most severe winter conditions will still occur in Gulf of Bothnia, while the mildest in the Southern Baltic Sea). The most significant changes are likely to occur in the Southern Baltic, where some winters without ice cover in the Vistula Lagoon may happen. Nonetheless, some extremely severe winters will occur and also within specific seasons more winters with a lower number of days with ice will occur.

  18. Changing seasonality of the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Kahru, Mati; Elmgren, Ragnar; Savchuk, Oleg P.

    2016-02-01

    Changes in the phenology of physical and ecological variables associated with climate change are likely to have significant effect on many aspects of the Baltic ecosystem. We apply a set of phenological indicators to multiple environmental variables measured by satellite sensors for 17-36 years to detect possible changes in the seasonality in the Baltic Sea environment. We detect significant temporal changes, such as earlier start of the summer season and prolongation of the productive season, in several variables ranging from basic physical drivers to ecological status indicators. While increasing trends in the absolute values of variables like sea-surface temperature (SST), diffuse attenuation of light (Ked490) and satellite-detected chlorophyll concentration (CHL) are detectable, the corresponding changes in their seasonal cycles are more dramatic. For example, the cumulative sum of 30 000 W m-2 of surface incoming shortwave irradiance (SIS) was reached 23 days earlier in 2014 compared to the beginning of the time series in 1983. The period of the year with SST of at least 17 °C has almost doubled (from 29 days in 1982 to 56 days in 2014), and the period with Ked490 over 0.4 m-1 has increased from about 60 days in 1998 to 240 days in 2013 - i.e., quadrupled. The period with satellite-estimated CHL of at least 3 mg m-3 has doubled from approximately 110 days in 1998 to 220 days in 2013. While the timing of both the phytoplankton spring and summer blooms have advanced, the annual CHL maximum that in the 1980s corresponded to the spring diatom bloom in May has now shifted to the summer cyanobacteria bloom in July.

  19. Dynamics of sea ice in the Baltic Sea and applications

    NASA Astrophysics Data System (ADS)

    Leppäranta, M.; Andrejev, O.; Oikkonen, A.

    2009-04-01

    Sea ice forms in the Baltic Sea annually. Coastal and archipelago areas are covered by landfast ice, while further offshore the ice drifts under the influence of winds and currents. The length scale of the Baltic Sea basins is 100 km and the scale of the ice thickness is ½ m, and the characteristics of the ice dynamics are similar to the ice dynamics in the polar seas. The drifting of the ice has major practical implications. First, the navigation conditions are determined by the ice extent, presence of leads and ice pressure, and therefore the dynamical behaviour of ice may cause rapid changes for them. Recent research has focused on ice kinematics scales, evolution of landfast ice zone, and downscaling of pressure from mesoscale models to ship scales. The length scale of dynamics depends on the ice thickness showing up in the stiffness of the ice and expansion of the landfast ice zone. Oil spills are in particular difficult in drift ice conditions, which has led to development of oil spill drift and dispersion models. This is most critical in the Gulf of Finland, a narrow and shallow basin with large oil terminals in the eastern side. The formation of sea ice ridges has important consequences in shallow basins since they ground to scour the bottom and form tie points for the expansion of the landfast ice.

  20. Future Climate Change in the Baltic Sea Area

    NASA Astrophysics Data System (ADS)

    Bøssing Christensen, Ole; Kjellström, Erik; Zorita, Eduardo; Sonnenborg, Torben; Meier, Markus; Grinsted, Aslak

    2015-04-01

    Regional climate models have been used extensively since the first assessment of climate change in the Baltic Sea region published in 2008, not the least for studies of Europe (and including the Baltic Sea catchment area). Therefore, conclusions regarding climate model results have a better foundation than was the case for the first BACC report of 2008. This presentation will report model results regarding future climate. What is the state of understanding about future human-driven climate change? We will cover regional models, statistical downscaling, hydrological modelling, ocean modelling and sea-level change as it is projected for the Baltic Sea region. Collections of regional model simulations from the ENSEMBLES project for example, financed through the European 5th Framework Programme and the World Climate Research Programme Coordinated Regional Climate Downscaling Experiment, have made it possible to obtain an increasingly robust estimation of model uncertainty. While the first Baltic Sea assessment mainly used four simulations from the European 5th Framework Programme PRUDENCE project, an ensemble of 13 transient regional simulations with twice the horizontal resolution reaching the end of the 21st century has been available from the ENSEMBLES project; therefore it has been possible to obtain more quantitative assessments of model uncertainty. The literature about future climate change in the Baltic Sea region is largely built upon the ENSEMBLES project. Also within statistical downscaling, a considerable number of papers have been published, encompassing now the application of non-linear statistical models, projected changes in extremes and correction of climate model biases. The uncertainty of hydrological change has received increasing attention since the previous Baltic Sea assessment. Several studies on the propagation of uncertainties originating in GCMs, RCMs, and emission scenarios are presented. The number of studies on uncertainties related to

  1. The regional geology and hydrocarbon potential of the Baltic Sea

    SciTech Connect

    Haselton, T.M. ); Brangulis, A.P.; Margulis, L.S. ); Kanev, S. )

    1991-08-01

    The Baltic Sea is roughly equivalent in size to the North Sea. Like the North Sea, is has an excellent oil prone source rock present over most of the area. In the entire Baltic Sea about 40 wells have been drilled. During the 1980s, exploration was carried out in the Soviet, Polish, and East German sectors of the Baltic Sea by Petrobaltic. Twenty-eight wells were drilled, 14 of which tested hydrocarbons. Two wells have been drilled in Danish waters and 11 in Swedish waters - all dry holes. Most of the Baltic Sea is included in the Baltic syneclise. In the deepest part of the basin a full Paleozoic and Mesozoic section is present. Major structural features are associated with reactivation of old basement faults. Most hydrocarbon discoveries are associated with structural arches. Exploration targets are Cambrian sandstones and Ordovician and Silurian reefs. The major discoveries are the B3 field in Poland and the D6 field offshore Lithuania and Kaliningrad, both of which have in-place reserves of around 100 million bbl. The Teisseyre-Tornquist line to the southwest represents the plate boundary between the East European platform and Europe. Repeated strike slip movements along this zone result in a complex pattern of extensional and compressional features in the Danish and German sectors. Primary exploration targets include Permian carbonates and sandstones as well as older zones. Gas has been tested in the German sector onshore.

  2. The history of sturgeon in the Baltic Sea

    USGS Publications Warehouse

    Popovic, Danijela; Panagiotopoulou, Hanna; Baca, Mateusz; Stefaniak, Krzysztof; Mackiewicz, Pawel; Makowiecki, Daniel; King, Tim L.; Gruchota, Jakub; Weglenski, Piotr; Stankovic, Anna

    2014-01-01

    For the past 2000 years at least, A. o. oxyrinchus has been the dominant sturgeon in the Baltic Sea, indicating a much earlier origin than previously suggested. The most similar extant sturgeon populations to the extinct Baltic stock are those from the St John and St Lawrence rivers in Canada. These populations should be considered the best source of breeding material for the ongoing sturgeon restitution programmes in Poland and Germany.

  3. Long-term characteristics of simulated ice deformation in the Baltic Sea (1962-2007)

    NASA Astrophysics Data System (ADS)

    LöPtien, U.; MâRtensson, S.; Meier, H. E. M.; HöGlund, A.

    2013-02-01

    The North Atlantic Oscillation (NAO) index is a frequently used measure for the mean winter conditions in Northern Europe. A positive, high index is associated with strong westerlies and anomalous warm temperatures. The effects on sea ice conditions in the Baltic Sea are twofold. Warm temperatures prevent sea ice formation. If ice is present nevertheless, the strong winds can promote the formation of ice ridges which hinders ship traffic. We use an ocean-sea ice model to investigate the NAO impact on the ridged ice area fraction in the Baltic during 1962-2007. Our simulations indicate that in the northern Bothnian Bay, a high NAO index is related to an anomalous accumulation of ridges, while in the rest of the Baltic Sea, the relationship is contrary. The NAO explains locally at most only 20-25% of the ridged ice fraction interannual variability which indicates the systems complexity. However, we find high skill with local correlations around 0.8 for annually averaged ridged ice fraction reconstructed from multilinear regression using winter averaged wind extremes, surface air temperature, and sea surface temperature (SST). This suggests that the amount of ridged ice in late winter can be derived from these routinely measured quantities. In large parts of the basin, it is sufficient to use the atmospheric parameters as a predictor, while in the eastern Bothnian Bay and southern Gulf of Finland, the SST is required to reconstruct the bulk of the ridged ice fraction.

  4. Population genetic structure of mussels from the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Bulnheim, H.-P.; Gosling, E.

    1988-03-01

    In a macrogeographic survey, the population genetic structure of mussels from various regions of the Baltic Sea, a large semi-enclosed brackish-water basin, was examined with reference to Mytilus edulis and M. galloprovincialis samples from the North Sea, Irish coast and southern Portugal. Electrophoretically detectable variation was analysed at 6 polymorphic enzyme loci ( Ap, Est-D, Lap-2, Odh, Pgi and Pgm). Evidence was provided of a remarkably large amount of biochemical genetic differentiation among ecologically and morphologically divergent mussel populations in the Baltic. Patterns of allele frequencies in low-salinity populations from the area of the Baltic Proper were demonstrated to be widely homogeneous but contrast strongly with those of the western Baltic, the latter resembling populations from marine habitats of the North Sea. Associated with a pronounced salinity gradient, the spatial heterogeneity in gene-pool structure is indicated by steep clines of allele frequency changes in the area of the eastern Danish isles. The adaptive significance of the observed allozymic variation is suggested. From genetic distance estimates, the subdivision of population structure is discussed in relation to the significant amount of differentiation detected within Mytilus populations to date and to the evolutionary time required for the divergence of Baltic mussel populations. The allozymic data provide evidence for the genetic distinctiveness of mussels from the low-salinity areas of the Baltic. Their position at the specific or subspecific level of classification requires further consideration.

  5. The Baltic Sea natural long-term variability of salinity

    NASA Astrophysics Data System (ADS)

    Schimanke, Semjon; Markus Meier, H. E.

    2015-04-01

    The Baltic Sea is one of the largest brackish sea areas of the world. The sensitive state of the Baltic Sea is sustained by a fresh-water surplus by river discharge and precipitation on one hand as well as inflows of highly saline and oxygen-rich water masses from the North Sea on the other. Major inflows which are crucial for the renewal of the deep water occur very intermittent with a mean frequency of approximately one per year. Stagnation periods (periods without major inflows) lead for instance to a reduction of oxygen concentration in the deep Baltic Sea spreading hypoxic conditions. Depending on the amount of salt water inflow and fresh-water supply the deep water salinity of the Baltic Sea varies between 11 to 14 PSU on the decadal scale. The goal of this study is to understand the contribution of different driving factors for the decadal to multi-decadal variability of salinity in the Baltic Sea. Continuous measurement series of salinity exist from the 1950 but are not sufficiently long for the investigation of long-term fluctuations. Therefore, a climate simulation of more than 800 years has been carried out with the Rossby Center Ocean model (RCO). RCO is a biogeochemical regional climate model which covers the entire Baltic Sea. It is driven with atmospheric data dynamical downscaled from a GCM mimicking natural climate variability. The analysis focus on the role of variations in river discharge and precipitation, changes in wind speed and direction, fluctuations in temperature and shifts in large scale pressure patterns (e.g. NAO). Hereby, the length of the simulation will allow to identify mechanisms working on decadal to multi-decadal time scales. Moreover, it will be discussed how likely long stagnation periods are under natural climate variability and if the observed exceptional long stagnation period between 1983-1993 might be related to beginning climate change.

  6. Postglacial paleoceanographic environments in the Barents and Baltic seas

    NASA Astrophysics Data System (ADS)

    Ivanova, E. V.; Murdmaa, I. O.; Emelyanov, E. M.; Seitkalieva, E. A.; Radionova, E. P.; Alekhina, G. N.; Sloistov, S. M.

    2016-01-01

    This paper presents reconstructions of ice sheet boundaries, lacustrine and marine paleobasins, as well as the connections of the Barents and Baltic seas with the North Atlantic from the Last Glacial Maximum to the Holocene. The reconstructions are based on original and published data obtained from the northern and western parts of the Barents Sea and Baltic depressions with account for the available regional schematic maps of deglaciation. The early deglaciation of the Scandinavian-Barents ice sheet culminated with the Bølling-Allerød interstadial (14.5-12.9 cal ka BP), which was characterized by a more vigorous Atlantic meridional overturning circulation (AMOC) and a corresponding increase in surface Atlantic water inflow into the Barents Sea through deep troughs. The Baltic Ice Lake (BIL) remained a dammed-up isolated basin during deglaciation from 16.0 to 11.7 cal ka BP. In the Younger Dryas (YD), the lake drained into the North Sea and was replaced by a brackish Yoldia Sea (YS) at the beginning of the Holocene (Preboreal, 11.7-10.7 cal ka BP), due to a limited connection between two basins through the Närke Strait. In the Barents Sea, the next increase in the Atlantic water influx into the deep basins corresponded to terminal YD and Preboreal events with a culmination in the Early Holocene. The Yoldia Sea became a lake again during the next stage, the Ancylus (~10.7-8.8 cal ka BP). Atlantic water inflow both into the Barents and Baltic seas varied during the Holocene, with a maximum contribution in the Early Holocene, when the Littorina Sea (LS, 8-4 cal ka BP) connection with the North Sea via the Danish Straits was formed to replace the Ancylus Lake. The recent, post-Littorina stage (PS, the last 4 cal ka) of the Baltic Sea evolution began in the Late Holocene.

  7. BALTEX - A science broker for the Baltic Sea Region

    NASA Astrophysics Data System (ADS)

    Reckermann, M.; von Storch, H.; Langner, J.; Omstedt, A. T.

    2010-12-01

    BALTEX (the Baltic Sea Experiment) is an interdisciplinary research network of scientists involved in environmental research dedicated to the Baltic Sea drainage basin (including disciplines such as meteorology, hydrology, oceanography, biogeochemistry and climate research). Originally founded in 1992 as a Continental Scale Experiment in GEWEX (the Global Energy and Water Cycle Experiment within the World Climate Research Programme (WCRP) of the World Meteorological Organization, WMO), it was intended to form a common science, communication and data platform with the overall goal to integrate efforts to gain a better understanding of the water and energy cycle in the Baltic Sea basin. BALTEX Phase II (since 2003) has extended the scope to research on regional climate change and variability, climate change impacts on biogeochemistry and water management, but also made first steps towards overarching social and political issues as cross-cutting activities in the context of the scientific objectives. An important aspect of BALTEX Phase II is a more holistic approach towards observing, understanding and modelling major environmental relevant for the entire Baltic Sea region. Parts of the BALTEX Phase II research activities thus contribute to the establishment of a high resolution integrated modelling system for Northern Europe, embedded in an Earth System Model. An outstanding product of BALTEX as a “knowledge broker” for regional political institutions is the BACC report. Following to a large extent the method of IPCC, a regional assessment report on climate change in the Baltic Sea basin was compiled, which summarizes the published scientifically legitimate knowledge on regional climate change in the Baltic Sea basin and its impacts. The assessment, known as the BACC report (BALTEX Assessment of Climate Change for the Baltic Sea Basin; BACC author team 2008, Reckermann et al., 2008) was published in 2008 as a book. A survey among climate researchers in the area

  8. Importance of coastal primary production in the northern Baltic Sea.

    PubMed

    Ask, Jenny; Rowe, Owen; Brugel, Sonia; Strömgren, Mårten; Byström, Pär; Andersson, Agneta

    2016-10-01

    In this study, we measured depth-dependent benthic microalgal primary production in a Bothnian Bay estuary to estimate the benthic contribution to total primary production. In addition, we compiled data on benthic microalgal primary production in the entire Baltic Sea. In the estuary, the benthic habitat contributed 17 % to the total annual primary production, and when upscaling our data to the entire Bothnian Bay, the corresponding value was 31 %. This estimated benthic share (31 %) is three times higher compared to past estimates of 10 %. The main reason for this discrepancy is the lack of data regarding benthic primary production in the northern Baltic Sea, but also that past studies overestimated the importance of pelagic primary production by not correcting for system-specific bathymetric variation. Our study thus highlights the importance of benthic communities for the northern Baltic Sea ecosystem in general and for future management strategies and ecosystem studies in particular. PMID:27075572

  9. Projected habitat loss for Atlantic herring in the Baltic Sea.

    PubMed

    Illing, Björn; Moyano, Marta; Hufnagl, Marc; Peck, Myron A

    2016-02-01

    Projected, climate-driven changes in rainfall patterns are expected to alter the salinity (S) of estuaries and larger brackish water bodies, such as the Baltic Sea. Some marine fish larvae are potentially more sensitive to low salinity than older stages, hence we compared the low salinity tolerance of Atlantic herring (Clupea harengus) larvae at the individual and population levels including four populations in the North and Baltic Seas. Acute low salinity tolerance was similar (S = 1.9-2.7) across populations and increased with increasing body size. Based on this physiological threshold and a regionally down-scaled climate model, spawning habitats in the northern and eastern Baltic Sea are projected to be largely unsuitable for herring by 2100. Although adaptive mechanisms may attenuate the effect in some species, the limited physiological tolerance of fish larvae will remain an important bottleneck for the persistence of marine fish populations in brackish waters undergoing climate-driven freshening.

  10. The Baltic Klint beneath the central Baltic Sea and its comparison with the North Estonian Klint

    NASA Astrophysics Data System (ADS)

    Tuuling, Igor; Flodén, Tom

    2016-06-01

    Along its contact with the Baltic Shield, the margin of the East European Platform reveals a well-developed, flooded terraced relief. The most striking and consistent set of escarpments at the contact of the Lower Palaeozoic calcareous and terrigenous rocks, known as the Baltic Klint (BK), extends from northwest of Russia to the Swedish island of Öland. Marine seismic reflection profiling in 1990-2004 revealed the central Baltic Sea Klint (BSK) section in detail and enabled comparison of its geology/geomorphology with a classical klint-section onshore, namely the North Estonian Klint (NEK). The conception of the BK onshore, which is based on the land-sea separating terraced relief in northern Estonia, is not fully applicable beneath the sea. Therefore, we consider that the BSK includes the entire terraced Cambrian outcrop. We suggest the term "Baltic Klint Complex" to include the well-terraced margin of the Ordovician limestone outcrop, which is weakly developed in Estonia. Because of a steady lithological framework of the bedrock layers across the southern slope of the Fennoscandian Shield, the central BSK in the western and the NEK in the eastern part of the Baltic Homocline have largely identical morphologies. The North Estonian Ordovician limestone plateau with the calcareous crest of the BK extends across the central Baltic Sea, whereas morphological changes/variations along the Klint base occur due to the east-westerly lithostratigraphic/thickness changes in the siliciclastic Cambrian sequence. The verge of the NEK, located some 30-50 m above sea level, starts to drop in altitude as its east-westerly course turns to northeast-southwest in western Estonia. Further westwards, the BK shifts gradually into southerly deepening (0.1-0.2°) layers as its crest drops to c. 150 m below sea level (b.s.l.) near Gotska Sandön. This course change is accompanied by a considerable decrease in thickness of the platform sedimentary cover, as below the central Baltic Sea the

  11. Echoes from the past: a healthy Baltic Sea requires more effort.

    PubMed

    Kotilainen, Aarno T; Arppe, Laura; Dobosz, Slawomir; Jansen, Eystein; Kabel, Karoline; Karhu, Juha; Kotilainen, Mia M; Kuijpers, Antoon; Lougheed, Bryan C; Meier, H E Markus; Moros, Matthias; Neumann, Thomas; Porsche, Christian; Poulsen, Niels; Rasmussen, Peter; Ribeiro, Sofia; Risebrobakken, Bjørg; Ryabchuk, Daria; Schimanke, Semjon; Snowball, Ian; Spiridonov, Mikhail; Virtasalo, Joonas J; Weckström, Kaarina; Witkowski, Andrzej; Zhamoida, Vladimir

    2014-02-01

    Integrated sediment multiproxy studies and modeling were used to reconstruct past changes in the Baltic Sea ecosystem. Results of natural changes over the past 6000 years in the Baltic Sea ecosystem suggest that forecasted climate warming might enhance environmental problems of the Baltic Sea. Integrated modeling and sediment proxy studies reveal increased sea surface temperatures and expanded seafloor anoxia (in deep basins) during earlier natural warm climate phases, such as the Medieval Climate Anomaly. Under future IPCC scenarios of global warming, there is likely no improvement of bottom water conditions in the Baltic Sea. Thus, the measures already designed to produce a healthier Baltic Sea are insufficient in the long term. The interactions between climate change and anthropogenic impacts on the Baltic Sea should be considered in management, implementation of policy strategies in the Baltic Sea environmental issues, and adaptation to future climate change.

  12. Echoes from the past: a healthy Baltic Sea requires more effort.

    PubMed

    Kotilainen, Aarno T; Arppe, Laura; Dobosz, Slawomir; Jansen, Eystein; Kabel, Karoline; Karhu, Juha; Kotilainen, Mia M; Kuijpers, Antoon; Lougheed, Bryan C; Meier, H E Markus; Moros, Matthias; Neumann, Thomas; Porsche, Christian; Poulsen, Niels; Rasmussen, Peter; Ribeiro, Sofia; Risebrobakken, Bjørg; Ryabchuk, Daria; Schimanke, Semjon; Snowball, Ian; Spiridonov, Mikhail; Virtasalo, Joonas J; Weckström, Kaarina; Witkowski, Andrzej; Zhamoida, Vladimir

    2014-02-01

    Integrated sediment multiproxy studies and modeling were used to reconstruct past changes in the Baltic Sea ecosystem. Results of natural changes over the past 6000 years in the Baltic Sea ecosystem suggest that forecasted climate warming might enhance environmental problems of the Baltic Sea. Integrated modeling and sediment proxy studies reveal increased sea surface temperatures and expanded seafloor anoxia (in deep basins) during earlier natural warm climate phases, such as the Medieval Climate Anomaly. Under future IPCC scenarios of global warming, there is likely no improvement of bottom water conditions in the Baltic Sea. Thus, the measures already designed to produce a healthier Baltic Sea are insufficient in the long term. The interactions between climate change and anthropogenic impacts on the Baltic Sea should be considered in management, implementation of policy strategies in the Baltic Sea environmental issues, and adaptation to future climate change. PMID:24414805

  13. Parasitism at the ecosystem level in the Baltic Sea.

    PubMed

    Zander, C D; Reimer, L W

    2002-01-01

    The Baltic Sea is characterized by organisms that can tolerate brackish water. Because of the Sea's history during glacial times, its flora and fauna (and also their parasites) can be traced to marine, freshwater and genuine brackish elements beside glacial relics. Snails, planktonic copepods, benthic amphipods and isopods are important intermediate hosts of diverse helminths; in addition polychaetes, bivalves and fishes may also act as final hosts. The most important final hosts, beside fishes, were seals and birds; these were able to disperse the parasites over the whole of the Baltic. Decreasing salinity from west to east limits the distribution of many parasites. Several marine and genuine brackish water species have almost spread over the whole Baltic. Freshwater species, however, have a lower tolerance than marine species and are only rarely found in the western part. A serious problem in the Baltic is eutrophication which can lead to massive abundances of generalist parasites, in host populations as well as host individuals. The final stage of this influence can cause a general decrease of host abundance and, as a consequence, of all kinds of parasites, due to oxygen deficiency. In comparison with the species spectrum of other brackish waters in Europe, the Baltic presents some endemic parasites as well as sharing parasite species with the Mediterranean and even the Black Sea. PMID:12396220

  14. IODP expedition 347: Baltic Sea basin paleoenvironment and biosphere

    NASA Astrophysics Data System (ADS)

    Andrén, T.; Barker Jørgensen, B.; Cotterill, C.; Green, S.; IODP expedition 347 scientific party, the

    2015-12-01

    The Integrated Ocean Drilling Program (IODP) expedition 347 cored sediments from different settings of the Baltic Sea covering the last glacial-interglacial cycle. The main aim was to study the geological development of the Baltic Sea in relation to the extreme climate variability of the region with changing ice cover and major shifts in temperature, salinity, and biological communities. Using the Greatship Manisha as a European Consortium for Ocean Research Drilling (ECORD) mission-specific platform, we recovered 1.6 km of core from nine sites of which four were additionally cored for microbiology. The sites covered the gateway to the North Sea and Atlantic Ocean, several sub-basins in the southern Baltic Sea, a deep basin in the central Baltic Sea, and a river estuary in the north. The waxing and waning of the Scandinavian ice sheet has profoundly affected the Baltic Sea sediments. During the Weichselian, progressing glaciers reshaped the submarine landscape and displaced sedimentary deposits from earlier Quaternary time. As the glaciers retreated they left a complex pattern of till, sand, and lacustrine clay, which in the basins has since been covered by a thick deposit of Holocene, organic-rich clay. Due to the stratified water column of the brackish Baltic Sea and the recurrent and widespread anoxia, the deeper basins harbor laminated sediments that provide a unique opportunity for high-resolution chronological studies. The Baltic Sea is a eutrophic intra-continental sea that is strongly impacted by terrestrial runoff and nutrient fluxes. The Holocene deposits are recorded today to be up to 50 m deep and geochemically affected by diagenetic alterations driven by organic matter degradation. Many of the cored sequences were highly supersaturated with respect to methane, which caused strong degassing upon core recovery. The depth distributions of conservative sea water ions still reflected the transition at the end of the last glaciation from fresh-water clays to

  15. Attribution of storm surge events in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Klehmet, Katharina; Burkhardt, Rockel

    2016-04-01

    In November 1995 and 2006 severe storm surges occurred along the German Baltic Sea coast. Water level heights of 1.8 m above sea level were observed at tide gauges in German coastal cities as e.g. Wismar and Flensburg. Within the attribution science an interesting aspect to consider is whether individual extreme events of e.g. heat waves, droughts or storm surges can be related to human-induced climate change or natural climate variability. The question arises whether these individual storm surges of 1995 and 2006 in the Baltic Sea have changed due to human influence on climate or whether the knowledge is still too vague to obtain robust information of attribution. We explore this question using two 15-member ensembles of Hadley Centre Global Environmental Model version 3-A (HadGEM3-A) as atmospheric forcing data for the regional ocean model TRIM-NP to downscale with 12.8 km spatial resolution and to calculate water level in the Baltic Sea. The ensemble of HadGEM3-A consists of two multi-decadal experiments from 1960-2013 - one with and one without anthropogenic forcings representing the actual and the natural climate respectively. This study, which is part of the EUCLEIA project (EUropean CLimate and weather Events: Interpretation and Attribution), will describe assessments of the human influence on the probability of occurrence of storm surge events in the German Baltic Sea.

  16. Climate change effects on the Baltic Sea borderland between land and sea.

    PubMed

    Strandmark, Alma; Bring, Arvid; Cousins, Sara A O; Destouni, Georgia; Kautsky, Hans; Kolb, Gundula; de la Torre-Castro, Maricela; Hambäck, Peter A

    2015-01-01

    Coastal habitats are situated on the border between land and sea, and ecosystem structure and functioning is influenced by both marine and terrestrial processes. Despite this, most scientific studies and monitoring are conducted either with a terrestrial or an aquatic focus. To address issues concerning climate change impacts in coastal areas, a cross-ecosystem approach is necessary. Since habitats along the Baltic coastlines vary in hydrology, natural geography, and ecology, climate change projections for Baltic shore ecosystems are bound to be highly speculative. Societal responses to climate change in the Baltic coastal ecosystems should have an ecosystem approach and match the biophysical realities of the Baltic Sea area. Knowledge about ecosystem processes and their responses to a changing climate should be integrated within the decision process, both locally and nationally, in order to increase the awareness of, and to prepare for climate change impacts in coastal areas of the Baltic Sea.

  17. Sea level trends for all sections of the Baltic Sea coastline

    NASA Astrophysics Data System (ADS)

    Madsen, Kristine S.; Høyer, Jacob L.; Suursaar, Ülo; Knudsen, Per; She, Jun

    2016-04-01

    To better understand influence of sea level rise on societal vulnerability and coastal erosion processes, it is important to know the sea level trend. The coastline of the Baltic Sea is not uniformly exposed, and therefore we will determine the sea level trend of the last 10, 50 and 100 years for all sections of the coastline. The observational record of sea level in the Baltic Sea is quite unique with several records of more than 100 years of data. However, the information is confined to the tide gauge locations. Here, we utilize a statistical method based on least squares regression and originally developed for short term sea level variability (Madsen et al. 2015, JGR, doi:10.1002/2015JC011070) to spread out the sea level information from selected tide gauges to all sections of the Baltic Sea coast. Monthly mean tide gauge observations are retrieved from PSMSL and supplemented with Estonian observations. The spatial distribution of the sea level is obtained from model reanalysis from the Copernicus Marine Service and satellite altimetry observations and land rise information is taken into account. Results are validated against independent tide gauges, providing a consistent record of 20th century sea level trends and variability, including uncertainties, for the entire Baltic Sea coastline. This work is sponsored by the EMODnet project Baltic Checkpoint.

  18. Breaker zone aerosol dynamics in the southern Baltic Sea

    SciTech Connect

    Zielinski, T.; Zielinski, A.

    1994-12-31

    This paper presents the results of lidar based investigations of aerosol concentrations and their size distributions over the breaker zones. The measurements were carried out under various weather conditions over breaker zones of the Gulf of Gdansk (1992) and from a station on the open Baltic Sea (International Experiment BAEX in 1993).

  19. Past Occurrences of Hypoxia in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Zillen, L.; Conley, D. J.; Bjorck, S.

    2007-12-01

    The hypoxic zone in the Baltic Sea has increased in area by about four times since 1950. Widespread oxygen deficiency below the halocline has severely reduced macro benthic communities in the Baltic Proper and the Gulf of Finland over the past decades and negatively effected food chain dynamics, fish habitats and fisheries in the entire Baltic Sea. In addition, hypoxia alters nutrient biogeochemical cycles. The cause of the increased hypoxia is believed to be enhanced eutrophication through increased anthropogenic input of nutrients, such as phosphorous and nitrogen. Conditions prior to the 1950s are considered as the benchmark and some authors suggest that the earlier Baltic Sea was an oligothrophic, clear-water body with oxygenated deep waters. By contrast, studies of short sediment cores reveal that hypoxia has been present in some of the deepest basins for at least the last 100-200 years. In addition, long sediment cores suggest that hypoxia in the Baltic Sea has occurred intermittently in deep basins over the last c. 8500 years. Thus, the occurrence of present day hypoxia in the deeper basins need not necessarily be attributed to human activity but rather to natural oceanographic, geologic and climate conditions. We present a compilation of previous publications that reported the occurrence of laminated sediments (i.e. a palaeo-proxy for hypoxia) in the Baltic Sea. This review shows that the deeper parts of the Baltic Sea have experienced either intermittent or more regular hypoxia during most of the Holocene and that more continuous laminations started to form c. 7800-8500 cal. yr BP ago, in association with the establishment of a permanent halocline during the transition from the Ancylus Lake to the Littorina Sea. Laminated sediments were more common during the early and late Holocene and coincided with intervals of high organic productivity (high TOC content) and high salinity during the Holocene Thermal Maximum and the Medieval Climate Optimum. This study

  20. Eemian sea-level highstand in the eastern Baltic Sea linked to long-duration White Sea connection

    NASA Astrophysics Data System (ADS)

    Miettinen, Arto; Head, Martin J.; Knudsen, Karen Luise

    2014-02-01

    Revised diatom and new dinoflagellate cyst and benthic foraminiferal data from the eastern Baltic Sea have refined our understanding of Eemian (Last Interglacial; 131-119.5 ka) sea-level change on the Russian Karelia, a former seaway linking the Baltic to the White Sea. Results from Peski, eastern Baltic show the initiation of marine conditions just before 131 ka in the latest Saalian, after the opening of a connection to the North Sea. Following the onset of the Eemian marine highstand and the opening of the White Sea connection at around 130.25 ka, near-fully marine conditions persisted in the eastern Baltic area for ca 6 kyr, until ca 124 ka. For most of the Eemian, a strong thermal stratification in the eastern Baltic resulted from an Arctic and possible North Atlantic water component from the White Sea merging with warmer waters from the North Sea. From ca 124 ka, decreasing salinity indicates the end of the marine highstand and a simultaneous closure of the Baltic Sea-White Sea connection, i.e. a duration of ca 6 kyr for this seaway. The main influence of White Sea inflow appears to be restricted to the eastern Baltic area, although a large submerged area in the Russian Karelia associated with temperate Atlantic waters could have assisted in creating a more oceanic climate for Central Europe.

  1. Baltic Sea nutrient reductions--what should we aim for?

    PubMed

    Ahtiainen, Heini; Artell, Janne; Elmgren, Ragnar; Hasselström, Linus; Håkansson, Cecilia

    2014-12-01

    Nutrient load reductions are needed to improve the state of the Baltic Sea, but it is still under debate how they should be implemented. In this paper, we use data from an environmental valuation study conducted in all nine Baltic Sea states to investigate public preferences of relevance to three of the involved decision-dimensions: First, the roles of nitrogen versus phosphorus reductions causing different eutrophication effects; second, the role of time - the lag between actions to reduce nutrient loads and perceived improvements; and third; the spatial dimension and the roles of actions targeting the coastal and open sea environment and different sub-basins. Our findings indicate that respondents view and value the Baltic Sea environment as a whole, and are not focussed only on their local sea area, or a particular aspect of water quality. We argue that public preferences concerning these three perspectives should be one of the factors guiding marine policy. This requires considering the entire range of eutrophication effects, in coastal and open sea areas, and including long-term and short-term measures.

  2. Evidence of chromosomal damage in common eiders (Somateria mollissima) from the Baltic Sea.

    PubMed

    Matson, Cole W; Franson, J Christian; Hollmén, Tuula; Kilpi, Mikael; Hario, Martti; Flint, Paul L; Bickham, John W

    2004-12-01

    Common eiders nesting in the Baltic Sea are exposed to generally high levels of contaminants including potentially genotoxic polycyclic aromatic hydrocarbons and organochlorines. Blood samples were collected from eiders at eight sites in the Baltic Sea and two sites in the Beaufort Sea. DNA content variation was estimated using the flow cytometric method, and subsequently utilized as a biomarker of genetic damage. We observed no significant differences in genetic damage among populations within either the Baltic or Beaufort Seas. However, eider populations from the Baltic Sea had significantly elevated estimates of genetic damage compared to populations from the Beaufort Sea. PMID:15556194

  3. Evidence of chromosomal damage in common eiders (Somateria mollissima) from the Baltic Sea

    USGS Publications Warehouse

    Matson, C.W.; Franson, J.C.; Hollmén, Tuula E.; Kilpi, Mikael; Hario, Martti; Flint, P.L.; Bickham, J.W.

    2004-01-01

    Common eiders nesting in the Baltic Sea are exposed to generally high levels of contaminants including potentially genotoxic polycyclic aromatic hydrocarbons and organochlorines. Blood samples were collected from eiders at eight sites in the Baltic Sea and two sites in the Beaufort Sea. DNA content variation was estimated using the flow cytometric method, and subsequently utilized as a biomarker of genetic damage. We observed no significant differences in genetic damage among populations within either the Baltic or Beaufort Seas. However, eider populations from the Baltic Sea had significantly elevated estimates of genetic damage compared to populations from the Beaufort Sea.

  4. Evaluation of Baltic Sea transport properties using particle tracking

    NASA Astrophysics Data System (ADS)

    Dargahi, Bijan; Cvetkovic, Vladimir

    2014-05-01

    Particle tracking model (PTM) is an effective tool for quantifying transport properties of large water bodies such as the Baltic Sea. We have applied PTM to our fully calibrated and validated Baltic Sea 3D hydrodynamic model for a 10-years period (2000-9). One hundred particles were released at a constant rate during an initial 10-days period from all the Baltic Sea sub-basins, the major rivers, and the open boundary in the Arkona Basin. In each basin, the particles were released at two different depths corresponding to the deep water and middle water layers. The objectives of the PTM simulations were to analyse the intra-exchange processes between the Baltic Sea basins and to estimate the arrival times and the paths of particles released from the rivers. The novel contribution of this study is determining the paths and arrival times of deeper water masses rather than the surface masses. Advective and diffusive transport processes in the Bornholm and Arkona basins are both driven by the interacting flows of the northern basins of the Baltic Sea and the North Sea. Particles released from Arkona basin flows northwards along the Stople Channel. The Gotland basins are the major contributors to the exchange process in the Baltic Sea. We find high values of the advection ratio, indicative of a forced advective transport process. The Bay of Gdansk is probably the most vulnerable region in the Baltic Sea. This is despite the fact that the main exchanging basins are the Bornholm Sea and the Easter Gotland Basin. The main reason is the intensive supply of the particles from the northern basins that normally take about 3000 days to reach the Bay of Gdansk. The process maintains a high level of particle concentration (90%) along its coastlines even after the 10-years period. Comparing the particle paths in the Western and Eastern Gotland basins two interesting features were found. Particles travelled in all four directions in the former basin and the middle layer particles

  5. Intrusion of radioactive industrially polluted water from North Sea into central Baltic Sea

    SciTech Connect

    Vakulovskiy, S.M.; Nikitin, A.I.

    1985-02-01

    The problem of penetration of radioactive industrially polluted water into the central Baltic Sea was studied. The content of Cs-134 as determined in water near the bottom of deep water trenches along the path traveled by North Sea water entering the Baltic. Samples were taken at 5 locations, with Cs-134 concentrated from samples of several thousands of liters. It was found that radioactive pollution caused by the entry of water from the North Sea extends through the system of deep water depressions into the Baltic as far as the Gotland trench. The greatest degree of contamination is found in the Arkona depression adjacent to the straits. The concentration of Cs-134 in the Gdansk trench is one-half as great and in the Gotland trench one-third as great as in the Arkona depression. Radioactive contamination in the Baltic is attributed to discharge of radioactive wastes by plants at Windscale.

  6. Cyclic volatile methylsiloxanes in fish from the Baltic Sea.

    PubMed

    Kierkegaard, Amelie; Bignert, Anders; McLachlan, Michael S

    2013-10-01

    Laboratory studies suggest that the cyclic volatile methylsiloxanes (cVMS) octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclohexasiloxane (D6) will persist in the aquatic environment and bioaccumulate in fish. Here these cVMS were measured in herring collected in the Swedish waters of the Baltic Sea and the North Sea and in grey seals from the Baltic Proper. D4, D5, and D6 were present in herring muscle at concentrations around 10, 200, and 40ngg(-1) lipid weight, respectively. The ratio of these concentrations was similar to the relative magnitude of estimated emissions to water, suggesting that the efficiency of overall transfer through the environment and food web was similar (within a factor 2-3) for the three chemicals. The concentrations of D5 and D6 were similar in herring caught in the highly populated Baltic Proper and in the less populated Bothnian Sea and Bothnian Bay. The D4 concentrations were lower at the most remote northern station, suggesting that D4 is less persistent than D5 and D6. Herring from the North Sea had lower levels of all three chemicals. The concentrations of D4, D5 and D6 in grey seal blubber were lower than the lipid normalized concentrations in herring, indicating that they do not biomagnify in grey seals.

  7. A new radiation model for Baltic Sea ecosystem modelling

    NASA Astrophysics Data System (ADS)

    Neumann, Thomas; Siegel, Herbert; Gerth, Monika

    2015-12-01

    Photosynthetically available radiation (PAR) is one of the key requirements for primary production in the ocean. The ambient PAR is determined by incoming solar radiation and optical properties of sea water and the optically active water constituents along the radiation pathway. Especially in coastal waters, the optical properties are affected by terrigenous constituents like yellow substances as well as high primary production. Numerical models for marine ecosystems account for the optical attenuation process in different ways and details. For the consideration of coloured dissolved organic matter (CDOM) and shading effects of phytoplankton particles, we propose a dynamic parametrization for the Baltic Sea. Furthermore, products from biological turnover processes are implemented. Besides PAR and its attenuation coefficient, the model calculates the Secchi disk depth, a simple measurable parameter describing the transparency of the water column and a water quality parameter in the European Water Framework Directive. The components of the proposed optical model are partly implemented from other publications respectively derived from our own measurements for the area of investigation. The model allows a better representation of PAR with a more realistic spatial and temporal variability compared to former parametrizations. The effect is that regional changes of primary production, especially in the northern part of the Baltic Sea, show reduced productivity due to higher CDOM concentrations. The model estimates for Secchi disk depth are much more realistic now. In the northern Baltic Sea, simulated oxygen concentrations in deep water have improved considerably.

  8. Hypoxia-related processes in the Baltic Sea.

    PubMed

    Conley, Daniel J; Björck, Svante; Bonsdorff, Erik; Carstensen, Jacob; Destouni, Georgia; Gustafsson, Bo G; Hietanen, Susanna; Kortekaas, Marloes; Kuosa, Harri; Meier, H E Markus; Müller-Karulis, Baerbel; Nordberg, Kjell; Norkko, Alf; Nürnberg, Gertrud; Pitkänen, Heikki; Rabalais, Nancy N; Rosenberg, Rutger; Savchuk, Oleg P; Slomp, Caroline P; Voss, Maren; Wulff, Fredrik; Zillén, Lovisa

    2009-05-15

    Hypoxia, a growing worldwide problem, has been intermittently present in the modern Baltic Sea since its formation ca. 8000 cal. yr BP. However, both the spatial extent and intensity of hypoxia have increased with anthropogenic eutrophication due to nutrient inputs. Physical processes, which control stratification and the renewal of oxygen in bottom waters, are important constraints on the formation and maintenance of hypoxia. Climate controlled inflows of saline water from the North Sea through the Danish Straits is a critical controlling factor governing the spatial extent and duration of hypoxia. Hypoxia regulates the biogeochemical cycles of both phosphorus (P) and nitrogen (N) in the water column and sediments. Significant amounts of P are currently released from sediments, an order of magnitude larger than anthropogenic inputs. The Baltic Sea is unique for coastal marine ecosystems experiencing N losses in hypoxic waters below the halocline. Although benthic communities in the Baltic Sea are naturally constrained by salinity gradients, hypoxia has resulted in habitat loss over vast areas and the elimination of benthic fauna, and has severely disrupted benthic food webs. Nutrient load reductions are needed to reduce the extent, severity, and effects of hypoxia. PMID:19544833

  9. Projected future climate change and Baltic Sea ecosystem management

    NASA Astrophysics Data System (ADS)

    Andersson, Agneta

    2015-04-01

    Climate change is likely to have large effects on the Baltic Sea ecosystem. Simulations indicate 2-4oC warming and 50-80% decreasing ice cover by 2100. Precipitation may increase ~30% in the north, causing increased land runoff of allochthonous organic matter (AOM) and organic pollutants. Salinity will decrease by about 2 units. Coupled physical-biogeochemical models indicate that in the south, bottom-water anoxia may spread, reducing cod recruitment and increasing sediment phosphorus release, promoting cyanobacterial blooms. In the north, heterotrophic bacteria will be favoured by AOM while phytoplankton may become hampered. More trophic levels in the food web will increase energy losses and consequently reduce fish production. Future management of the Baltic Sea must consider effects of climate change on the ecosystem dynamics and functions, as well as effects of anthrophogenic nutrient and pollutant load. Monitoring should have a holistic approach and encompass both autotrophic (phytoplankton) and heterotrophic (e.g. bacterial) processes.

  10. Numerical investigations of future ice conditions in the Baltic Sea.

    PubMed

    Haapala, J; Meier, H E; Rinne, J

    2001-08-01

    Global climate changes is expected to have an effect on the physical and ecological characteristics of the Baltic Sea. Estimates of future climate on the regional scale can be obtained by using either statistical or dynamical downscaling methods of global AOGCM scenario results. In this paper, we use 2 different coupled ice-ocean models of the Baltic Sea to simulate present and future ice conditions around 100 years from present. Two 10-year time slice experiments have been performed using the results of atmospheric climate model simulations as forcing, one representing pre-industrial climate conditions (control simulation), and the other global warming with a 150% increase in CO2 greenhouse gas concentration (scenario simulation). Present-day climatological ice conditions and interannual variability are realistically reproduced by the models. The simulated range of the maximum annual ice extent in the Baltic in both models together is 180 to 420 x 10(3) km2 in the control simulation and 45 to 270 x 10(3) km2 in the scenario simulation. The range of the maximum annual ice thickness is from 32 to 96 cm and from 11 to 60 cm in the control and scenario simulations, respectively. In contrast to earlier estimates, sea ice is still formed every winter in the Northern Bothnian Bay and in the most Eastern parts of the Gulf of Finland. Overall, the simulated changes of quantities such as ice extent and ice thickness, as well as their interannual variations are relatively similar in both models, which is remarkable, because the 2 coupled ice-ocean model systems have been developed independently. This increases the reliability of future projections of ice conditions in the Baltic Sea. PMID:11697256

  11. Deoxygenation of the Baltic Sea during the last century.

    PubMed

    Carstensen, Jacob; Andersen, Jesper H; Gustafsson, Bo G; Conley, Daniel J

    2014-04-15

    Deoxygenation is a global problem in coastal and open regions of the ocean, and has led to expanding areas of oxygen minimum zones and coastal hypoxia. The recent expansion of hypoxia in coastal ecosystems has been primarily attributed to global warming and enhanced nutrient input from land and atmosphere. The largest anthropogenically induced hypoxic area in the world is the Baltic Sea, where the relative importance of physical forcing versus eutrophication is still debated. We have analyzed water column oxygen and salinity profiles to reconstruct oxygen and stratification conditions over the last 115 y and compare the influence of both climate and anthropogenic forcing on hypoxia. We report a 10-fold increase of hypoxia in the Baltic Sea and show that this is primarily linked to increased inputs of nutrients from land, although increased respiration from higher temperatures during the last two decades has contributed to worsening oxygen conditions. Although shifts in climate and physical circulation are important factors modulating the extent of hypoxia, further nutrient reductions in the Baltic Sea will be necessary to reduce the ecosystems impacts of deoxygenation.

  12. Regional Ocean Colour Remote Sensing Algorithm for the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Hieronymi, Martin; Muller, Dagmar; Krasemann, Hajo; Schonfeld, Wolfgang; Rottgers, Rudiger; Doerffer, Roland

    2015-12-01

    The Baltic Sea is a challenging study site from an optically point of view. Its partly highly absorbing waters are mainly associated with the presence of coloured dissolved organic matter and often accompanied by non-algae absorbing particles. In addition, the Baltic Sea area is characterised by massive annual surface blooms of cyanobacteria. In Europe, the Baltic Sea is a very specific and important case study with intense user interest. In the framework of different research projects as the “Ocean Colour Climate Change Initiative”, the “SEOM OC Extreme Case 2 Waters”, and partly “MyOcean”, we aim to develop an optimised, error-characterised, regional ocean colour processor applicable to several satellite sensors, like MODIS, MERIS, VIIRS, and OLCI. The procedure, which is used to determine inherent optical properties and different water constituents’ concentrations from remote sensing reflectance, is an artificial Neural Network (NN). We provide first results of comparisons of in-situ data with different ocean colour products.

  13. Deoxygenation of the Baltic Sea during the last century

    PubMed Central

    Carstensen, Jacob; Andersen, Jesper H.; Gustafsson, Bo G.; Conley, Daniel J.

    2014-01-01

    Deoxygenation is a global problem in coastal and open regions of the ocean, and has led to expanding areas of oxygen minimum zones and coastal hypoxia. The recent expansion of hypoxia in coastal ecosystems has been primarily attributed to global warming and enhanced nutrient input from land and atmosphere. The largest anthropogenically induced hypoxic area in the world is the Baltic Sea, where the relative importance of physical forcing versus eutrophication is still debated. We have analyzed water column oxygen and salinity profiles to reconstruct oxygen and stratification conditions over the last 115 y and compare the influence of both climate and anthropogenic forcing on hypoxia. We report a 10-fold increase of hypoxia in the Baltic Sea and show that this is primarily linked to increased inputs of nutrients from land, although increased respiration from higher temperatures during the last two decades has contributed to worsening oxygen conditions. Although shifts in climate and physical circulation are important factors modulating the extent of hypoxia, further nutrient reductions in the Baltic Sea will be necessary to reduce the ecosystems impacts of deoxygenation. PMID:24706804

  14. Response of the Baltic and North Seas to river runoff from the Baltic watershed - Physical and biological changes

    NASA Astrophysics Data System (ADS)

    Hänninen, Jari; Vuorinen, Ilppo; Rajasilta, Marjut; Reid, Philip C.

    2015-11-01

    Selected Baltic Sea watershed River Runoff (BSRR) events during 1970-2000 were used as predictor in Generalised Linear Mixed Models (GLIMMIX) for evidence of simultaneous changes/chain of events (including possible time lags) in some chemical, physical and biological variables in the Baltic and North Sea ecosystems. Our aim was to explore for climatic-based explanation for ecological regime shifts that were documented semi-simultaneously in both ecosystems. Certain similarities were identified in the North Sea and the Baltic Sea salinity, oxygen concentration, temperature and phyto- and zooplankton parameters. These findings suggest that BSRR events which originate in the Baltic Sea catchment area modify and contribute to large scale ecosystem changes not only in the Baltic Sea, but also in the adjacent parts of the North Sea. However, the Baltic Sea inter-annual and inter-decadal variabilities of physical and biological parameters are driven by direct atmospheric forcing, typically with a relatively short lag. In contrast, such changes in the North Sea are influenced by both local and direct atmospheric forcing, typically with a longer lag than in the Baltic, and a more regional, indirect forcing from changes in the North Atlantic. We suggest that this interactive system partially is behind large scale ecosystem regime shifts found in both Seas. During our study period two such shifts have been identified independently from us in a study earlier in the Southern and Central Baltic in 1980s and 1990s and a later one in 2001/2002 in the North Sea. As a post hoc test we compared the 0+ year class strength of the North Sea herring with BSRR intensity, and found evidence for higher herring production in high BSRR periods, which further corroborates the idea of a remote effect from the large watershed area of the Baltic. Regime shifts as well as their semi-synchronous appearance in two neighbouring sea areas could be identified. GLIMMIX models provide opportunities for

  15. Sea ice in the Baltic Sea - revisiting BASIS ice, a~historical data set covering the period 1960/1961-1978/1979

    NASA Astrophysics Data System (ADS)

    Löptien, U.; Dietze, H.

    2014-06-01

    The Baltic Sea is a seasonally ice-covered, marginal sea, situated in central northern Europe. It is an essential waterway connecting highly industrialised countries. Because ship traffic is intermittently hindered by sea ice, the local weather services have been monitoring sea ice conditions for decades. In the present study we revisit a historical monitoring data set, covering the winters 1960/1961. This data set, dubbed Data Bank for Baltic Sea Ice and Sea Surface Temperatures (BASIS) ice, is based on hand-drawn maps that were collected and then digitised 1981 in a joint project of the Finnish Institute of Marine Research (today Finish Meteorological Institute (FMI)) and the Swedish Meteorological and Hydrological Institute (SMHI). BASIS ice was designed for storage on punch cards and all ice information is encoded by five digits. This makes the data hard to access. Here we present a post-processed product based on the original five-digit code. Specifically, we convert to standard ice quantities (including information on ice types), which we distribute in the current and free Network Common Data Format (NetCDF). Our post-processed data set will help to assess numerical ice models and provide easy-to-access unique historical reference material for sea ice in the Baltic Sea. In addition we provide statistics showcasing the data quality. The website baltic-ocean.org"target="_blank">www.baltic-ocean.org hosts the post-prossed data and the conversion code. The data are also archived at the Data Publisher for Earth & Environmental Science PANGEA (doi:10.1594/PANGEA.832353).

  16. Monthly Ensembles in Algal Bloom Predictions on the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Roiha, Petra; Westerlund, Antti; Stipa, Tapani

    2010-05-01

    In this work we explore the statistical features of monthly ensembles and their capability to predict biogeochemical conditions in the Baltic Sea. Operational marine environmental modelling has been considered hard, and consequently there are very few operational ecological models. Operational modelling of harmful algal blooms is harder still, since it is difficult to separate the algal species in models, and in general, very little is known of HAB properties. We present results of an ensemble approach to HAB forecasting in the Baltic, and discuss the applicability of the forecasting method to biochemical modelling. It turns out that HABs are indeed possible to forecast with useful accuracy. For modelling the algal blooms in Baltic Sea we used FMI operational 3-dimensional biogeochemical model to produce seasonal ensemble forecasts for different physical, chemical and biological variables. The modelled variables were temperature, salinity, velocity, silicate, phosphate, nitrate, diatoms, flagellates and two species of potentially toxic filamentous cyanobacteria nodularia spumigena and aphanizomenon flos-aquae. In this work we concentrate to the latter two. Ensembles were produced by running the biogeochemical model several times and forcing it on every run with different set of seasonal weather parameters from ECMWF's mathematically perturbed ensemble prediction forecasts. The ensembles were then analysed by statistical methods and the median, quartiles, minimum and maximum values were calculated for estimating the probable amounts of algae. Validation for the forecast method was made by comparing the final results against available and valid in-situ HAB data.

  17. Characterisation of juvenile flatfish habitats in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Florin, Ann-Britt; Sundblad, Göran; Bergström, Ulf

    2009-04-01

    Survival and growth of the earliest life-stages is considered a key factor in determining the abundance of many marine fish species. For flatfishes, the availability of high quality nursery areas is essential for successful recruitment. Regarding the Baltic Sea, there are large gaps in knowledge on factors that influence the distribution of flatfishes during this sensitive stage. To identify the characteristics of important nursery areas in the Baltic for flounder ( Platichthys flesus) and turbot ( Psetta maxima), a field survey with push net sampling was conducted in the northern Baltic proper during autumn 2006. The sampling stations were stratified to cover several different habitat types defined by substrate and wave exposure. Apart from density of young-of-the-year (YOY) flatfishes, a number of ecological characteristics of the habitat were recorded. Physical habitat variables included substrate type, salinity, depth, turbidity, vegetation and habitat structure. Variables describing biotic processes, such as prey availability and abundance of competitors, were also sampled. The relationships between the spatial distribution of species and these ecological characteristics were fitted to presence/absence data of juvenile flatfish using generalized additive models (GAM). The best habitat descriptors for flounder in order of contribution were: substrate, habitat structure, salinity, wave exposure and occurrence of filamentous algae. Positive effects of increasing wave exposure, salinity and structure were detected while a high cover of filamentous algae had a negative effect. Sand and gravel were preferred over soft and stony substrates. For turbot the best habitat descriptors in order of contribution were: occurrence of filamentous algae, substrate and turbidity. Turbot showed a preference for areas with a low cover of filamentous algae, high turbidity and sandy substrate. Prey availability and abundance of competitors were not included in the models, indicating

  18. One hundred years of hydrographic measurements in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Fonselius, Stig; Valderrama, Jorge

    2003-06-01

    The first measurements of salinity of the deep water in the open Baltic Sea were made in the last decades of the 1800s. At a Scandinavian science meeting in Copenhagen in 1892, Professor Otto Pettersson from Sweden suggested that regular measurements of hydrographic parameters should be carried out at some important deep stations in the Baltic Sea. His suggestion was adopted and since that time we have rather complete hydrographical data from the Bornholm Deep, the Gotland Deep, and the Landsort Deep and from some stations in the Gulf of Bothnia. The measurements were interrupted in the Baltic Proper during the two World Wars. At the beginning only salinity, temperature and dissolved oxygen were measured and one or two expeditions were carried out annually, mostly in summer. In the 1920s also alkalinity and pH were occasionally measured and total carbonate was calculated. A few nutrient measurements were also carried out. After World War II we find results from four or more expeditions every year and intercalibration of methods was arranged. Results of temperature, salinity and dissolved oxygen measurements from the Bornholm Deep, the Gotland Deep, the Landsort Deep and salinity measurements from three stations in the Gulf of Bothnia, covering the whole 20th century are presented and discussed. The salinity distribution and the variations between oxygen and hydrogen sulphide periods in the deep water of the Gotland Deep and the Landsort Deep are demonstrated. Series of phosphate and nitrate distribution in the Gotland Deep are shown from the 1950s to the present and the effects of the stagnant conditions are briefly discussed. Two large inflows of highly saline water, the first during the First World War and the second in 1951, are demonstrated. The 20th century minimum salinity of the bottom water in the Baltic Proper in 1992 is discussed.

  19. Paleogeographic sedimentation settings in the northern Baltic Sea

    NASA Astrophysics Data System (ADS)

    Trimonis, E. S.; Emelyanov, E. M.; Vaikutene, G.

    2008-10-01

    The grain-size and chemical composition of the bottom sediments and their diatom assemblages from the northern Baltic Sea is discussed. Characteristic layers are distinguished based on the lithostratgraphy and sediment core correlation, which reflect the transition from the lacustrine to marine sedimentation settings during the initial Holocene. Sediment cores demonstrate lateral variations in the sedimentation patterns during the marine (Yoldia Sea), the lacustrine (Ancylus Lake), and the subsequent marine (Littorina Sea) stages: first two stages were characterized by the clay deposition, while the latter one featured accumulation of silty-clayey and clayey muds in bottom depressions. Sea-level fluctuations and corresponding environmental changes are recorded in microlaminated sequences, in particular, sapropelic muds.

  20. Geodetic observation of sea-level change and crustal deformation in the Baltic Sea region

    NASA Astrophysics Data System (ADS)

    Richter, A.; Groh, A.; Dietrich, R.

    Based on tide gauge observations spanning almost 200 years, homogeneous time series of the mean relative sea level were derived for nine sites at the southern coast of the Baltic Sea. Our regionally concentrated data were complemented by long-term relative sea-level records retrieved from the data base of the Permanent Service for Mean Sea Level (PSMSL). From these records relative sea-level change rates were derived at 51 tide gauge stations for the period between 1908 and 2007. A minimum observation time of 60 years is required for the determination of reliable sea-level rates. At present, no anthropogenic acceleration in sea-level rise is detected in the tide gauge observations in the southern Baltic. The spatial variation of the relative sea-level rates reflects the fingerprint of GIA-induced crustal uplift. Time series of extreme sea levels were also inferred from the tide gauge records. They were complemented by water level information from historic storm surge marks preserved along the German Baltic coast. Based on this combined dataset the incidence and spatial variation of extreme sea levels induced by storm surges were analysed yielding important information for hazard assessments. Permanent GPS observations were used to determine recent crustal deformation rates for 44 stations in the Baltic Sea region. The GPS derived height change rates were applied to reduce the relative sea-level changes observed by tide gauges yielding an estimate for the eustatic sea-level change. For 13 tide gauge-GPS colocation sites a mean eustatic sea-level trend of 1.3 mm/a was derived for the last 100 years.

  1. Scientific support by the BONUS+ projects for the sustainability of the Baltic Sea Region: the case of the HELCOM Baltic Sea Action Plan.

    PubMed

    Kononen, Kaisa; Andrusaitis, Andris; Sirola, Maija

    2014-02-01

    The synthesis of the BONUS+ research is introduced. The HELCOM Baltic Sea Action Plan is examined as a case to illustrate the potentials and challenges in building the science-policy making interface on a macro regional level. The projects address environmental challenges in the Baltic Sea as defined by the Baltic Sea Action Plan, or consider the environmental governance and decision making within the Baltic Sea context in general. Eutrophication, biodiversity, hazardous substances, maritime activities, and the environment governance are addressed, as are cross cutting issues, such as the impact of climate change, maritime spatial planning and impacts of future development on ecosystem services. The projects contributed to relevant policy developments: 37 consultations carried out at EU level, 49 modifications to policy documents and action plans, 153 suggestions for the efficacy of pertinent public policies and governance, and in 570 occasions, scientists working in BONUS+ projects served as members or observers in scientific and stakeholder committees.

  2. Sources and pathways of polycyclic aromatic and saturated hydrocarbons in the Arkona Basin (Southern Baltic Sea, Central Europe)

    SciTech Connect

    Schulz, H.M.

    1996-12-31

    The Baltic Sea (Central Europe) is surrounded by coastal regions with long histories of industrialization. The heavy metal profiles in the sediments in the center of the Arkona Basin, one of the depressions of the southern Baltic Sea area, clearly reflect the historical anthropogenic influence. The Arkona Basin-is the final sink for materials derived from the Oder river which drains a highly polluted industrial area of Eastern Europe. Surficial muddy sediments from a close-meshed field of sampling-points were analyzed for distribution patterns of aliphatics and quantities and ratios of selected polycyclic aromatic hydrocarbons (PAH). These compounds are thought to reflect anthropogenic pollution related to emissions from traffic, heating, etc. We use these marker substances to test if the basin sediments reflect riverine input, and if additional sources can be identified.

  3. [Accumulation of polycyclic arenes in Baltic Sea algae].

    PubMed

    Veldre, I A; Itra, A R; Paal'me, L P; Kukk, Kh A

    1985-01-01

    The paper presents data on the level of benzo(a)pyrene (BP) and some other polycyclic arenes in alga and phanerogam specimens from different gulfs of the Baltic Sea. Algae were shown to absorb BP from sea water. The mean concentration of BP in sea water was under 0.004 microgram/1, while in algae it ranged 0.1-21.2 micrograms/kg dry weight. Algae accumulate BP to a higher degree than phanerogams. The highest concentrations of BP were found in algae Enteromorpha while the lowest ones in Furcellaria. In annual green algae, BP level was higher in autumn, i. e. at the end of vegetation period, than in spring. Brown algae Fucus vesiculosus is recommended for monitoring polycyclic arene pollution in the area from Vormsi Island to Käsmu and green algae Cladophora or Enteromorpha in the eastern part of the Finnish Gulf.

  4. [Accumulation of polycyclic arenes in Baltic Sea algae].

    PubMed

    Veldre, I A; Itra, A R; Paal'me, L P; Kukk, Kh A

    1985-01-01

    The paper presents data on the level of benzo(a)pyrene (BP) and some other polycyclic arenes in alga and phanerogam specimens from different gulfs of the Baltic Sea. Algae were shown to absorb BP from sea water. The mean concentration of BP in sea water was under 0.004 microgram/1, while in algae it ranged 0.1-21.2 micrograms/kg dry weight. Algae accumulate BP to a higher degree than phanerogams. The highest concentrations of BP were found in algae Enteromorpha while the lowest ones in Furcellaria. In annual green algae, BP level was higher in autumn, i. e. at the end of vegetation period, than in spring. Brown algae Fucus vesiculosus is recommended for monitoring polycyclic arene pollution in the area from Vormsi Island to Käsmu and green algae Cladophora or Enteromorpha in the eastern part of the Finnish Gulf. PMID:4060672

  5. Sedimentary record of environmental pollution in the Western Baltic Sea

    NASA Astrophysics Data System (ADS)

    Müller, German; Dominik, J.; Reuther, R.; Malisch, R.; Schulte, E.; Acker, L.; Irion, G.

    1980-12-01

    The chronological development of environmental pollution in the Western Baltic Sea for the past hundred years was investigated in dated sediment cores. An artificial radionuclide (137Cs), nutrients, heavy metals, chlorinated hydrocarbons (PCB, DDT, Lindane) and plasticizers (phthalate esters) show characteristic distribution patterns within the various cores. They can be related to the production and use of specific chemicals and goods, to emissions associated with the increased combustion of coal parallel to industrialization and —in the case of 137Cs — to emissions associated with atomic weapons tests in the high atmosphere. Characteristic trends in the general development of pollution may be superimposed by specific emissions from local sources.

  6. Variational data assimilation problem for the Baltic Sea thermodynamics

    NASA Astrophysics Data System (ADS)

    Zakharova, Natalia; Agoshkov, Valery; Parmuzin, Eugene

    2015-04-01

    The most versatile and promising technology for solving problems of monitoring and analysis of the natural environment is a four-dimensional variational data assimilation of observation data. In such problems not only the development and justification of algorithms for numerical solution of variational data assimilation problems but the properties of the optimal solution play an important role. In this work the variational data assimilation problems in the Baltic Sea water area were formulated and studied. Numerical experiments on restoring the ocean heat flux and obtaining solution of the system (temperature, salinity, velocity, and sea surface height) in the Baltic Sea primitive equation hydrodynamics model with assimilation procedure were carried out. In the calculations we used daily sea surface temperature observation from Danish meteorological Institute, prepared on the basis of measurements of the radiometer (AVHRR, AATSR and AMSRE) and spectroradiometer (SEVIRI and MODIS). The spatial resolution of the model grid with respect to the horizontal variables amounted to 0.0625x0.03125 degree. The results of the numerical experiments are presented. This study was supported by the Russian Foundation for Basic Research (project 13-01-00753, project 14-01-31195) and project 14-11-00609 by the Russian Science Foundation. References: 1 E.I. Parmuzin, V.I. Agoshkov, Numerical solution of the variational assimilation problem for sea surface temperature in the model of the Black Sea dynamics. Russ. J. Numer. Anal. Math. Modelling (2012) 27, No.1, 69-94 2 Zakharova N.B., Agoshkov V.I., Parmuzin E.I., The new method of ARGO buoys system observation data interpolation. Russian Journal of Numerical Analysis and Mathematical Modelling. Vol. 28, Issue 1, 2013. 3 Zalesny V.B., Gusev A.V., Chernobay S.Yu., Aps R., Tamsalu R., Kujala P., Rytkönen J. The Bal-tic Sea circulation modelling and assessment of marine pollution, Russ. J. Numer. Analysis and Math. Modelling, 2014, V 29

  7. Model simulation of inflow water to the Baltic Sea based on ¹²⁹I.

    PubMed

    Yi, P; Chen, X G; Bao, D X; Qian, R Z; Aldahan, A; Tian, F Y; Possnert, G; Bryhn, A C; Gu, T F; Hou, X L; He, P; Yu, Z B; Wang, B

    2013-12-01

    The semi-enclosed Baltic Sea represents a vital economic and recreational resource for more than 90 million people inhabiting its coasts. Extensive contamination of this sea by a variety of anthropogenic pollutants has raised the concern of the people in the region. Quantifying seawater inflow is crucial for estimating potential environmental risks as well as to find the best remedial strategy. We present here a model to estimate water inflow from the North Sea to the Baltic Sea by utilizing ¹²⁹I as a tracer. The results predicted inflow range of 230-450 km³/y with best fit value around 330 km³/y from the North Sea to the Baltic Sea during 1980-1999. Despite limited time series data on ¹²⁹I, the model presented here demonstrates a new management tool for the Baltic Sea to calculate inflow water compared to conventional methods (such as salinity, temperature and hydrographic models).

  8. Sea ice in the Baltic Sea - revisiting BASIS ice, a historical data set covering the period 1960/1961-1978/1979

    NASA Astrophysics Data System (ADS)

    Löptien, U.; Dietze, H.

    2014-12-01

    The Baltic Sea is a seasonally ice-covered, marginal sea in central northern Europe. It is an essential waterway connecting highly industrialised countries. Because ship traffic is intermittently hindered by sea ice, the local weather services have been monitoring sea ice conditions for decades. In the present study we revisit a historical monitoring data set, covering the winters 1960/1961 to 1978/1979. This data set, dubbed Data Bank for Baltic Sea Ice and Sea Surface Temperatures (BASIS) ice, is based on hand-drawn maps that were collected and then digitised in 1981 in a joint project of the Finnish Institute of Marine Research (today the Finnish Meteorological Institute (FMI)) and the Swedish Meteorological and Hydrological Institute (SMHI). BASIS ice was designed for storage on punch cards and all ice information is encoded by five digits. This makes the data hard to access. Here we present a post-processed product based on the original five-digit code. Specifically, we convert to standard ice quantities (including information on ice types), which we distribute in the current and free Network Common Data Format (NetCDF). Our post-processed data set will help to assess numerical ice models and provide easy-to-access unique historical reference material for sea ice in the Baltic Sea. In addition we provide statistics showcasing the data quality. The website http://www.baltic-ocean.org hosts the post-processed data and the conversion code. The data are also archived at the Data Publisher for Earth & Environmental Science, PANGAEA (doi:10.1594/PANGAEA.832353).

  9. Hypoxia sustains cyanobacteria blooms in the Baltic sea.

    PubMed

    Funkey, Carolina P; Conley, Daniel J; Reuss, Nina S; Humborg, Christoph; Jilbert, Tom; Slomp, Caroline P

    2014-01-01

    Nutrient over-enrichment is one of the classic triggering mechanisms for the occurrence of cyanobacteria blooms in aquatic ecosystems. In the Baltic Sea, cyanobacteria regularly occur in the late summer months and form nuisance accumulations in surface waters and their abundance has intensified significantly in the past 50 years attributed to human-induced eutrophication. However, the natural occurrence of cyanobacteria during the Holocene is debated. In this study, we present records of cyanobacteria pigments, water column redox proxies, and nitrogen isotopic signatures for the past ca. 8000 years from Baltic Sea sediment cores. Our results demonstrate that cyanobacteria abundance and nitrogen fixation are correlated with hypoxia occurring during three main intervals: (1) ca. 7000-4000 B.P. during the Littorina transgression, (2) ca. 1400-700 B.P. during the Medieval Climate Anomaly, and (3) from ca. 1950 A.D. to the present. Issues of preservation were investigated, and we show that organic matter and pigment profiles are not simply an artifact of preservation. These results suggest that cyanobacteria abundance is sustained during periods of hypoxia, most likely because of enhanced recycling of phosphorus in low oxygen conditions.

  10. Hypoxia sustains cyanobacteria blooms in the Baltic sea.

    PubMed

    Funkey, Carolina P; Conley, Daniel J; Reuss, Nina S; Humborg, Christoph; Jilbert, Tom; Slomp, Caroline P

    2014-01-01

    Nutrient over-enrichment is one of the classic triggering mechanisms for the occurrence of cyanobacteria blooms in aquatic ecosystems. In the Baltic Sea, cyanobacteria regularly occur in the late summer months and form nuisance accumulations in surface waters and their abundance has intensified significantly in the past 50 years attributed to human-induced eutrophication. However, the natural occurrence of cyanobacteria during the Holocene is debated. In this study, we present records of cyanobacteria pigments, water column redox proxies, and nitrogen isotopic signatures for the past ca. 8000 years from Baltic Sea sediment cores. Our results demonstrate that cyanobacteria abundance and nitrogen fixation are correlated with hypoxia occurring during three main intervals: (1) ca. 7000-4000 B.P. during the Littorina transgression, (2) ca. 1400-700 B.P. during the Medieval Climate Anomaly, and (3) from ca. 1950 A.D. to the present. Issues of preservation were investigated, and we show that organic matter and pigment profiles are not simply an artifact of preservation. These results suggest that cyanobacteria abundance is sustained during periods of hypoxia, most likely because of enhanced recycling of phosphorus in low oxygen conditions. PMID:24512281

  11. Hypoxia Sustains Cyanobacteria Blooms in the Baltic Sea

    PubMed Central

    2014-01-01

    Nutrient over-enrichment is one of the classic triggering mechanisms for the occurrence of cyanobacteria blooms in aquatic ecosystems. In the Baltic Sea, cyanobacteria regularly occur in the late summer months and form nuisance accumulations in surface waters and their abundance has intensified significantly in the past 50 years attributed to human-induced eutrophication. However, the natural occurrence of cyanobacteria during the Holocene is debated. In this study, we present records of cyanobacteria pigments, water column redox proxies, and nitrogen isotopic signatures for the past ca. 8000 years from Baltic Sea sediment cores. Our results demonstrate that cyanobacteria abundance and nitrogen fixation are correlated with hypoxia occurring during three main intervals: (1) ca. 7000–4000 B.P. during the Littorina transgression, (2) ca. 1400–700 B.P. during the Medieval Climate Anomaly, and (3) from ca. 1950 A.D. to the present. Issues of preservation were investigated, and we show that organic matter and pigment profiles are not simply an artifact of preservation. These results suggest that cyanobacteria abundance is sustained during periods of hypoxia, most likely because of enhanced recycling of phosphorus in low oxygen conditions. PMID:24512281

  12. Rock encrusting assemblages: Structure and distribution along the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Grabowska, Monika; Grzelak, Katarzyna; Kukliński, Piotr

    2015-09-01

    Aquatic community structure and dynamics are generally controlled by a variety of biological and physical factors. Among these factors in marine ecosystems, salinity is known to have a significant effect on species occurrence and composition. In this study, we investigated the large-scale distribution and abundance of encrusting fauna along a salinity gradient on the shallow Baltic Sea rocky coast. Rock samples collected from 14 locations distributed between the Gulf of Bothnia (salinity 0.6) and Skagerrak (salinity 28) supported a total number of 24 encrusting species. The faunas were composed mostly of marine species with opportunistic life histories; however, some brackish water specialists were also present. The number of species and abundance counts is strongly positively correlated with increases in salinity. No encrusting faunas were recorded below salinity level 4. Multivariate analysis (nMDS) revealed three major groups based on species composition that differed in terms of abundance and number of species. Each group was associated with specific salinity conditions. The first assemblage type occurred within salinity 4-7, the second within salinity between 22 and 27, and the third type was a mixture between the two observed at a salinity of approximately 17. This study indicates that to determine the assemblage structure of the Baltic Sea encrusting fauna, analyses at the family level were found to be a reliable surrogate for species composition.

  13. Atmospheric circulation and storm events in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Surkova, G. V.; Arkhipkin, Victor S.; Kislov, Alexander V.

    2015-09-01

    The storm events in the Baltic Sea are examined in connection with the main weather patterns grouped into the circulation types (CTs), and their changes in present climate. A calendar of storms was derived from results of wave model SWAN (Simulating WAves Nearshore) experiments for 1948-2011. Based on this calendar, a catalogue of atmospheric sea level pressure (SLP) fields was prepared for CTs from the NCEP/NCAR dataset. SLP fields were then analyzed using a pattern recognition algorithm which employed empirical orthogonal decomposition and cluster analysis. For every CT we conducted an analysis of their seasonal and interannual changes, along with their role in storm event formation. An increase of the storm CTs' frequency in the second part of the 20th century was shown to be in a close agreement with teleconnection circulation patterns such as the Arctic Oscillation, North Atlantic Oscillation and the Scandinavian blocking.

  14. Simulated sea surface temperature and heat fluxes in different climates of the Baltic Sea.

    PubMed

    Döscher, Ralf; Meier, H E Markus

    2004-06-01

    The physical state of the Baltic Sea in possible future climates is approached by numerical model experiments with a regional coupled ocean-atmosphere model driven by different global simulations. Scenarios and recent climate simulations are compared to estimate changes. The sea surface is clearly warmer by 2.9 degrees C in the ensemble mean. The horizontal pattern of average annual mean warming can largely be explained in terms of ice-cover reduction. The transfer of heat from the atmosphere to the Baltic Sea shows a changed seasonal cycle: a reduced heat loss in fall, increased heat uptake in spring, and reduced heat uptake in summer. The interannual variability of surface temperature is generally increased. This is associated with a smoothed frequency distribution in northern basins. The overall heat budget shows increased solar radiation to the sea surface, which is balanced by changes of the other heat flux components.

  15. Simulated sea surface temperature and heat fluxes in different climates of the Baltic Sea.

    PubMed

    Döscher, Ralf; Meier, H E Markus

    2004-06-01

    The physical state of the Baltic Sea in possible future climates is approached by numerical model experiments with a regional coupled ocean-atmosphere model driven by different global simulations. Scenarios and recent climate simulations are compared to estimate changes. The sea surface is clearly warmer by 2.9 degrees C in the ensemble mean. The horizontal pattern of average annual mean warming can largely be explained in terms of ice-cover reduction. The transfer of heat from the atmosphere to the Baltic Sea shows a changed seasonal cycle: a reduced heat loss in fall, increased heat uptake in spring, and reduced heat uptake in summer. The interannual variability of surface temperature is generally increased. This is associated with a smoothed frequency distribution in northern basins. The overall heat budget shows increased solar radiation to the sea surface, which is balanced by changes of the other heat flux components. PMID:15264603

  16. Spatial sensitivity of inorganic carbon to model setup: North Sea and Baltic Sea with ECOSMO

    NASA Astrophysics Data System (ADS)

    Castano Primo, Rocio; Schrum, Corinna; Daewel, Ute

    2015-04-01

    In ocean biogeochemical models it is critical to capture the key processes adequately so they do not only reproduce the observations but that those processes are reproduced correctly. One key issue is the choice of parameters, which in most cases are estimates with large uncertainties. This can be the product of actual lack of detailed knowledge of the process, or the manner the processes are implemented, more or less complex. In addition, the model sensitivity is not necessarily homogenous across the spatial domain modelled, which adds another layer of complexity to biogeochemical modelling. In the particular case of the inorganic carbon cycle, there are several sets of carbonate constants that can be chosen. The calculated air-sea CO2 flux is largely dependent on the parametrization chosen. In addition, the different parametrizations all the underlying processes that in some way impact the carbon cycle beyond the carbonate dissociation and fluxes give results that can be significantly different. Examples of these processes are phytoplankton growth rates or remineralization rates. Despite their geographical proximity, the North and Baltic Seas exhibit very different dynamics. The North Sea receives important inflows of Atlantic waters, while the Baltic Sea is an almost enclosed system, with very little exchange from the North Sea. Wind, tides, and freshwater supply act very differently, but dominantly structure the ecosystem dynamics on spatial and temporal scales. The biological community is also different. Cyanobacteria, which are important due to their ability to fix atmospheric nitrogen, and they are only present in the Baltic Sea. These differentiating features have a strong impact in the biogeochemical cycles and ultimately shape the variations in the carbonate chemistry. Here the ECOSMO model was employed on the North Sea and Baltic Sea. The model is set so both are modelled at the same time, instead of having them run separately. ECOSMO is a 3-D coupled

  17. Radioactive pollution of the waters of the baltic sea during 1986

    SciTech Connect

    Lazarev, L.N.; Kuznetsov, Yu.V.; Gedeonov, L.I.; Gavrilov, V.M.; Gritchenko, Z.G.; Ivanova, L.M.; Orlova, T.E.; Tishkova, N.A.

    1989-01-01

    Results are presented from an investigation of radioactive pollution of the waters of the Baltic Sea during 1986. Inhomogeneities in the pollution of this area of water, due to varying density of atmospheric radioactive fallout, are detected. It is found that among the radionuclides entering the surface of the Baltic Sea in 1986 as a result of atmospheric transport, the main one in terms of radiation dose is cesium-137. Comparisons are made of the level of cesium-137 content in the waters of the Baltic Sea in 1986 and in preceding years. It is noted that even in the most polluted regions of the sea the cesium-137 content was 500 times less than the maximum allowable concentration (MAC) in the USSR for drinking water. The first results of the determination of plutonium-239 and 240 in the Baltic Sea are presented.

  18. Recent trends in Sea ice in the southern and western Baltic and the North Sea

    NASA Astrophysics Data System (ADS)

    Holfort, Jürgen; Schmelzer, Natalija; Schwegmann, Sandra

    2016-04-01

    We analyzed sea ice charts and observations of a 50 year long period starting in 1961 to produce two climatological ice atlases, one for the western and southern Baltic and one for the German Bight and Limfjord. As the year to year variability is large we subdivided the 50 year into three overlapping 30 year periods (1961-1990, 1971-2000 and 1981-2010) to look for trends in the sea ice. In the southern and western Baltic as well as in the North Sea there was a clear decrease in the total frequency of ice occurrence. Other parameters like begin and end of the ice season, ice thickness, etc. did not show such clear signal and also showed larger regional differences. The ice conditions mainly changed in accordance with the changes in air temperature in the same period, although some more regional changes in some parameters were most probably also influenced by other factors like the deepening of fairways.

  19. Could seals prevent cod recovery in the Baltic Sea?

    PubMed

    MacKenzie, Brian R; Eero, Margit; Ojaveer, Henn

    2011-05-09

    Fish populations are increasingly affected by multiple human and natural impacts including exploitation, eutrophication, habitat alteration and climate change. As a result many collapsed populations may have to recover in ecosystems whose structure and functioning differ from those in which they were formerly productive and supported sustainable fisheries. Here we investigate how a cod (Gadus morhua) population in the Baltic Sea whose biomass was reduced due to a combination of high exploitation and deteriorating environmental conditions might recover and develop in the 21st century in an ecosystem that likely will change due to both the already started recovery of a cod predator, the grey seal Halichoerus grypus, and projected climate impacts. Simulation modelling, assuming increased seal predation, fishing levels consistent with management plan targets and stable salinity, shows that the cod population could reach high levels well above the long-term average. Scenarios with similar seal and fishing levels but with 15% lower salinity suggest that the Baltic will still be able to support a cod population which can sustain a fishery, but biomass and yields will be lower. At present knowledge of cod and seal interactions, seal predation was found to have much lower impact on cod recovery, compared to the effects of exploitation and salinity. These results suggest that dual management objectives (recovery of both seal and cod populations) are realistic but success in achieving these goals will also depend on how climate change affects cod recruitment.

  20. Population structure of flounder (Platichthys flesus) in the Baltic Sea: differences among demersal and pelagic spawners.

    PubMed

    Florin, A-B; Höglund, J

    2008-07-01

    We found significant population structure and isolation by distance among samples of flounder (Platichthys flesus) in the Baltic, Kattegat and Skagerrak seas using microsatellite genetic markers. This pattern was almost entirely due to a difference between flounder that have demersal spawning in the northern Baltic, as compared to pelagic spawners in the southern Baltic and on the west coast of Sweden. Among demersal spawners we found neither genetic differentiation nor any isolation by distance among sampling sites. We speculate that demersal flounder are descendants of a population that colonized the Baltic previous to pelagic spawners. The demersal flounder may thus have had longer time to adapt to the low salinity in the Baltic, and accordingly display egg characteristics that make it possible to reproduce at the low salinity levels in the northern Baltic. Among pelagic spawners significant isolation by distance was detected. Pelagic spawners have previously been shown to display clinal variation in egg size, which allows them to float also at the moderate salinity levels up to the region north of the island Bornholm. Management units for harvesting should ideally be based on true biological populations, and for the commercially important flounder up to 15 different management stocks in the Baltic have been suggested. We could not find a population genetic foundation for such a high number of management units, and our data suggest three management units: the northern Baltic (demersal populations), southern Baltic with the Oresund straits and the most northwestern sampling sites (Skagerrak, Kattegat and North Sea).

  1. Bacterial methanogenesis in holocene sediments in the Baltic Sea

    SciTech Connect

    Lein, A.Y.; Namsaraev, B.B.; Trotsyuk, V.Y.; Ivanov, M.V.

    1981-01-01

    Soviet biologists have found evidence of viable methanogenic microorganisms in mud samples collected in 1978 from the Baltic Sea by the research ship Academician Kurchatov. Experiments with radioactive carbon and direct measurements of the samples' methane concentrations led to several conclusions: (1) the process of bacterial methanogenesis occurs mainly via carbon dioxide reduction, (2) the methanogenic intensity depends on the depth of the deposited sediment and its distance from land; shallow-water sediments found in gulfs produced more methane than deepwater ones taken from low spots, (3) organic-matter consumption during bacterial methane reduction makes up 0.14-7.9 mg of carbon/kg of wet mud per year; this is over 20 times less than during bacterial sulfate reduction, (4) The bulk of the methane generated migrates from the muds into the water and (5) marine sediments are undersaturated with methane, suggesting that the methane migrates via filtration of pore waters, not by diffusion.

  2. Has eutrophication promoted forage fish production in the Baltic Sea?

    PubMed

    Eero, Margit; Andersson, Helén C; Almroth-Rosell, Elin; MacKenzie, Brian R

    2016-10-01

    Reducing anthropogenic nutrient inputs is a major policy goal for restoring good environmental status of coastal marine ecosystems. However, it is unclear to what extent reducing nutrients would also lower fish production and fisheries yields. Empirical examples of changes in nutrient loads and concurrent fish production can provide useful insights to this question. In this paper, we investigate to what extent a multi-fold increase in nutrient loads from the 1950s to 1980s enhanced forage fish production in the Baltic Sea. We use monitoring data on fish stock dynamics covering the period of the nutrient increase, combined with nutrient concentrations from a 3-dimensional coupled physical-biogeochemical ocean model. The results suggest that nutrient enrichment enhanced the biomass level of forage fish by up to 50 % in some years and areas due to increased body weight of fish. However, the trends in fish biomasses were generally decoupled from changes in nutrient concentrations. PMID:27170013

  3. Energy economy of salmon aquaculture in the Baltic sea

    NASA Astrophysics Data System (ADS)

    Folke, Carl

    1988-07-01

    Resource utilization in Atlantic salmon aquaculture in the Baltic Sea was investigated by means of an energy analysis. A comparison was made between cage farming and sea ranching enterprises each with yearly yields of 40 t of Atlantic salmon. A variety of sea ranching options were evaluated, including (a) conventional ranching, (b) ranching employing a delayed release to the sea of young smolts, (c) harvesting salmon both by offshore fishing fleets and as they return to coastal areas, and (d) when offshore fishing is banned, harvesting salmon only as they return to coastal areas where released. Inputs both from natural ecosystems (i.e., fish consumed by ranched salmon while in the sea and raw materials used for producing dry food pellets) and from the economy (i.e., fossil fuels and energy embodied in economic goods and services) were quantified in tonnes for food energy and as direct plus indirect energy cost (embodied energy). The fixed solar energy (estimated as primary production) and the direct and indirect auxiliary energy requirements per unit of fish output were expressed in similar units. Similar quantities of living resources in tonnes per unit of salmon biomass output are required whether the salmon are feeding in the sea or are caged farmed. Cage farming is about 10 times more dependent on auxiliary energies than sea ranching. Sea ranching applying delayed release of smolts is 35 45% more efficient in the use of auxiliary energies than conventional sea ranching and cage farming. Restriction of offshore fishing would make sea ranching 3 to 6.5 times more efficient than cage farming. The fixed solar energy input to Atlantic salmon aquaculture is 4 to 63 times larger than the inputs of auxiliary energy. Thus, cage farming and sea ranching are both heavily dependent on the productivity of natural ecosystems. It is concluded that sustainable development of the aquaculture industry must be founded on ecologically integrated technologies which utilize the free

  4. On Suspended matter grain size in Baltic sea

    NASA Astrophysics Data System (ADS)

    Bubnova, Ekaterina; Sivkov, Vadim; Zubarevich, Victor

    2016-04-01

    Suspended matter grain size data were gathered during the 25th research vessel "Akademik Mstislav Keldysh" cruise (1991, September-October). Initial quantitative data were obtained with a use of the Coulter counter and subsequently modified into volume concentrations (mm3/l) for size intervals. More than 80 samples from 15 stations were analyzed (depth range 0-355 m). The main goal of research was to illustrate the spatial variability of suspended matter concentration and dispersion in Baltic Sea. The mutual feature of suspended matter grain size distribution is the logical rise of particle number along with descending of particle's size. Vertical variability of grain size distribution was defined by Baltic Sea hydrological structure, including upper mixed layer - from the surface to the thermocline - with 35 m thick, cold intermediate layer - from the thermocline to the halocline- and bottom layer, which lied under the halocline. Upper layer showed a rise in total suspended matter concentration (up to 0.6 mm3/l), while cold intermediate level consisted of far more clear water (up to 0.1 mm3/l). Such a difference is caused by the thermocline boarding role. Meanwhile, deep bottom water experienced surges in suspended matter concentration owing to the nepheloid layer presence and "liquid bottom" effect. Coastal waters appeared to have the highest amount of particles (up to 5.0 mm3/l). Suspended matter grain size distribution in the upper mixed layer revealed a peak of concentration at 7 μ, which can be due to autumn plankton bloom. Another feature in suspended matter grain size distribution appeared at the deep layer below halocline, where both O2 and H2S were observed and red/ox barrier is. The simultaneous presence of Fe and Mn (in solutions below red/ox barrier) and O2 leads to precipitation of oxyhydrates Fe and Mn and grain size distribution graph peaking at 4.5 μ.

  5. Denitrification in the water column of the central Baltic Sea

    NASA Astrophysics Data System (ADS)

    Dalsgaard, Tage; De Brabandere, Loreto; Hall, Per O. J.

    2013-04-01

    Removal of fixed nitrogen in the water column of the eastern Gotland Basin, central Baltic Sea, was studied during two cruises in September 2008 and August 2010. The water column was stratified with anoxic sulfidic bottom water meeting oxic nitrate containing water at the oxic-anoxic interface. Anammox was never detected whereas denitrification was found in all incubations from anoxic depths and occurred immediately below the oxic-anoxic interface. Sulfide (H2S + HS- + S2-) was in most cases the only electron donor for denitrification but, in contrast to previous findings, denitrification was in some situations driven by organic matter alone. Nitrous oxide (N2O) became an increasingly important product of denitrification with increasing sulfide concentration and was >80% of the total N gas formation at 10 μM sulfide. The potential rates of denitrification measured in incubations at elevated NO3- or sulfide concentrations were converted to in situ rates using the measured water column concentrations of NO3- and sulfide and the actual measured relations between NO3- and sulfide concentrations and denitrification rates. In situ denitrification ranged from 0.24 to 15.9 nM N2 h-1. Assuming that these rates were valid throughout the anoxic NO3- containing zone, depth integrated in situ denitrification rates of 0.06-2.11 mmol N m-2 d-1 were estimated. The thickness of this zone was generally 3-6 m, which is probably what can be maintained through regular turbulent mixing induced by internal waves at the oxic-anoxic interface. However, layers of up to 55 m thickness with low O2 water (<10 μM) were observed which was probably the result of larger scale mixing. In such a layer nitrification may produce NO3- and once the O2 has been depleted denitrification will follow resulting in enormous rates per unit area. Even with an active denitrification layer of 3-6 m thickness the pelagic denitrification per unit area clearly exceeded sediment denitrification rates elsewhere in

  6. Occurence of Extreme Sea Level Events In The Coastal Waters of West Estonia, The Baltic Sea

    NASA Astrophysics Data System (ADS)

    Suursaar, Ü.; Kullas, T.; Otsmann, M.; Kõuts, T.

    Extreme low and high sea level events are analysed on the basis of available historical data and mechanisms of surges studied appplying the 1 km grid step 2D hydrodynamic model in the two nearly tideless semienclosed sub-basins of the Baltic Sea, the Gulf of Riga and the Väinameri. Based on the input and verification data from 1999, the water level is modelled with realistic and idealistic forcing schemes. The low level events are associated with the local wind pattern of easterly winds, determined by the corresponding regional air pressure fields above the Central Baltic. The high levels (up to 253 cm above the long-term average as measured in Pärnu) are associated with SW and W storms. They first appear due to the water volume change in the Baltic Sea, then due to an additional volume increase in the Gulf of Riga, and finally due to the local level slope in the narrow and shallow bays. An amplification due to resonance with seiche or Helmholtz oscillation periods is also possible. Simulations showed that the extreme high and low sea levels in some small bays of West Estonia without tide- gauges could exceed the corresponding values in the Pärnu Bay.

  7. Baltic Sea Ice Regional Indices and their relationship with atmospheric circulation patterns and maritime navigation

    NASA Astrophysics Data System (ADS)

    Sztobryn, M.; Kowalska, B.

    2009-04-01

    The Baltic navigation and urban activities of the coastal communities around the Baltic Sea depended always very much on the ice conditions in the sea. The sea ice occurs different in form and amount, depending on the sea area and the winter season. The aim of the work was the investigation of influence of atmospheric circulation patterns on sea ice condition of Baltic Sea (by the sea ice regional indices). The atmospheric circulation patterns were represented by the German Weather Service's - Grosswetterlagen. The relationship between the ice severity indices and icebreakers activities (number of cases, in which the Swedish and Finnish icebreakers assisted the ships) were investigated. The work was done under the Seaman project (Norwegian Financial Mechanism)

  8. Tritium volume activity in the Baltic Sea in 1987-1989

    SciTech Connect

    Styro, D.B.; Korotkov, V.P.

    1994-11-01

    Tritium volume activities measured in the Baltic Sea are summarized in this paper. Activity levels were determined by the liquid scintillation method with a LS-1000 counter. The field investigations showed that the tritium volume activity in the Baltic Sea can change substantially in absolute magnitude. Therefore, average volume activity is used as an indicator of natural content. Correlations between calculated (averaged) tritium activity levels and the Chernobyl accident are very briefly discussed. 7 refs., 2 figs., 1 tab.

  9. Investigating the influence of sea level oscillations in the Danish Straits on the Baltic Sea dynamics

    NASA Astrophysics Data System (ADS)

    Tikhonova, Natalia; Gusev, Anatoly; Diansky, Nikolay; Zakharchuk, Evgeny

    2016-04-01

    In this research, we study the influence of dynamic processes in the Danish Straits on the sea surface height (SSH) oscillations in the Baltic Sea. For this purpose, we use the model of marine and oceanic circulation INMOM (Institute of Numerical Mathematics Ocean Model). The simulations were carried out for the period 2009-2010, and the coastal station data were used for verification of SSH modelling quality. Comparison of the simulated data with the ones measured in the coastal points showed us that the model does not describe SSH variability in different areas of the Baltic Sea well enough, so in the following simulation series the in situ SSH data of the coastal measurements were assimilated at the open boundary in the Danish Straits. The results of the new simulation showed us that this approach significantly increases the SSH simulation quality in all areas of the sea, where the comparison was made. In particular, the correlation coefficients between the simulated and measured SSH data increased from 0.21-0.73 to 0.81-0.90. On the basis of these results, it has been suggested that the Baltic Sea SSH variability is largely determined by the influence of the dynamic processes in the Danish Straits, which can be represented as a superposition of oscillations of different space-time scales. These oscillations can either be generated in the straits themselves, or propagate from the North Sea. For verification of this hypothesis and assessment of the oscillation propagation distance in the Baltic Sea, the following experiment was performed. At the open boundary in the Danish Straits, the six harmonics were set with the following parameters: the periods are 1.5, 3.0, 6.0, 13.5, 40.5, and 121.5 days, and the amplitude for all the harmonics is 50 cm. The results showed us that the prescribed harmonic oscillations at the open boundary propagate into all areas of the sea without changing the frequency, but with decreasing amplitude. The decrease in amplitude is not

  10. Frequencies and pathways of deep cyclones forcing major inflows to the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Lehmann, Andreas; Myrberg, Kai; Höflich, Katharina; Getzlaff, Klaus

    2014-05-01

    The salt budget of the Baltic Sea is determined by a balance between saline inflow from the Kattegat and brackish water outflow from the Baltic through the Danish Straits. River runoff and precipitation cause dilution while evaporation acts in the opposite direction. Ice formation and melting act as evaporation and precipitation, respectively, but have no influence on an annual timescale. Generally, during dry periods the mean salinity of the Baltic Sea increases while during wet periods a decrease will happen. These long-term changes are overlaid by the atmospheric-driven water exchange between North Sea and Baltic Sea. The salinity and the stratification in the deep basins are linked to the occurrence of Major Baltic Inflows (MBIs) of higher saline water of North Sea origin, which occur sporadically and transport higher saline and oxygenated water to deeper layers. These major inflows are often followed by stagnation periods with no strong saline inflows, during which the permanent halocline weakens, even disappears in some basins, and extended areas of oxygen deficiency develop in those regions where the salinity stratification remains. Since the mid-1970s, the frequency and intensity of major inflows have decreased. They were completely absent between February 1983 and January 1993. However, in spite of the decreasing frequency of MBIs, there was no obvious decrease in the frequency of larger Baltic Sea volume changes. Generally, strong inflows to the Baltic Sea are driven by strong to very strong westerly winds. For most effective inflows the frequency and pathways of deep cyclones are important. Furthermore, Atlantic cyclone frequencies and associated storm tracks are highly correlated with the NAO. Based on NCEP/NCAR and ERA Interim SLP reanalysis data for the period 1950-2013, deep cyclones variability over the northern North Atlantic, North Sea and Baltic Sea region has been analyzed, and cyclones frequencies and characteristic pathways have been related

  11. Long-term model study of nutrient and detritus dynamics in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Kõuts, Mariliis; Raudsepp, Urmas; Maljutenko, Ilja; Liis Treimann, Meri

    2015-04-01

    Eutrophication resulting from direct and indirect input of nutrients is considered one of the major environmental problems in the sub-basins of the Baltic Sea. Stronger eutrophication is manifested through increased summer cyanobacteria blooms and expanding hypoxia. It has been recognized that cycling of organic matter is a considerable source of nutrients in the Baltic Sea. Nutrient pools in the sediments have increased over the last decades. Our study aims at understanding the eutrophication of the Baltic Sea by looking at spatial patterns and temporal variation of biogeochemical parameters. We are focusing on spatial detritus dynamics during the period of 40 years in the Baltic Sea. Model simulations were performed using a three-dimensional free-surface hydrodynamic model GETM coupled with the ERGOM biogeochemical model. The model domain covers the entire Baltic Sea area and the period modelled is 1966-2006. Our results show that nutrient and detritus dynamics differ between shallow and deep areas. Seasonal cycle is dominant in the shallow areas (water depth less than 60 m approximately) and nutrients - organic matter are recycling there. Deep areas, however, could be storage areas of organic matter where halocline acts as a kind of barrier for nutrients to be transported to the upper layer. Still, nutrients are mixed from the upper halocline into the upper layer and fuel primary production there. Deep areas therefore become important source of nutrients especially during MBIs. Horizontal transport of nutrients from upstream basins of the Baltic Sea is a considerable source of nutrients for downstream basins.

  12. Physical processes in the transition zone between North Sea and Baltic Sea. Numerical simulations and observations

    NASA Astrophysics Data System (ADS)

    Stanev, Emil V.; Lu, Xi; Grashorn, Sebastian

    2015-09-01

    The dynamics in the transition zone between the North Sea and Baltic Sea are analyzed here using data from a 22-year-long climatic simulation with a focus on the periods 1992-1994 and 2001-2003 when two recent major inflow events occurred. Observations from gauges and in situ measurements are used to validate the model. Parameters, which cannot be easily measured, such as water and salt transports through straits, have been compared against similar previous estimates. The good performance of simulations is attributed to the finer resolution of the model compared to earlier set ups. The outflow in the Kattegat, which is an analogue of the tidal outflows, tends to propagate to the North over the shallows without showing a substantial deflection to the right due to the Earth's rotation. The inflow follows the topography. The different inflow and outflow pathways are explained as a consequence of the specific combination of bathymetry, axial and lateral processes. The circulation in Kattegat is persistently clockwise with an eastern intensification during inflow and a western one during outflow regimes. The tidal wave there propagates as Kelvin wave, keeping the coast on its right. The flows in the two main straits reveal very different responses to tides, which are also highly asymmetric during inflow and outflow conditions. The circulation has a typical two-layer structure, the correlation between salinity and velocity tends to increase the salt transport in the salinity conveyor belt. The transversal circulation in the entrance of the Sound enhances the vertical mixing of the saltier North Sea water. The long-term averaged ratio of the water transports through the Great Belt and the Sound is ∼2.6-2.7 but this number changes reaching lower values during the major inflow in 1993. The transports in the straits are asymmetric. During inflow events the repartition of water penetrating the Baltic Sea is strongly in favor of the pathway through the Sound, which provides

  13. Impact of accelerated future global mean sea level rise on hypoxia in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Meier, H. E. M.; Höglund, A.; Eilola, K.; Almroth-Rosell, E.

    2016-08-01

    Expanding hypoxia is today a major threat for many coastal seas around the world and disentangling its drivers is a large challenge for interdisciplinary research. Using a coupled physical-biogeochemical model we estimate the impact of past and accelerated future global mean sea level rise (GSLR) upon water exchange and oxygen conditions in a semi-enclosed, shallow sea. As a study site, the Baltic Sea was chosen that suffers today from eutrophication and from dead bottom zones due to (1) excessive nutrient loads from land, (2) limited water exchange with the world ocean and (3) perhaps other drivers like global warming. We show from model simulations for the period 1850-2008 that the impacts of past GSLR on the marine ecosystem were relatively small. If we assume for the end of the twenty-first century a GSLR of +0.5 m relative to today's mean sea level, the impact on the marine ecosystem may still be small. Such a GSLR corresponds approximately to the projected ensemble-mean value reported by the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. However, we conclude that GSLR should be considered in future high-end projections (>+1 m) for the Baltic Sea and other coastal seas with similar hydrographical conditions as in the Baltic because GSLR may lead to reinforced saltwater inflows causing higher salinity and increased vertical stratification compared to present-day conditions. Contrary to intuition, reinforced ventilation of the deep water does not lead to overall improved oxygen conditions but causes instead expanded dead bottom areas accompanied with increased internal phosphorus loads from the sediments and increased risk for cyanobacteria blooms.

  14. Bioaccumulation of mercury in the trophic chain of flatfish from the Baltic Sea.

    PubMed

    Polak-Juszczak, Lucyna

    2012-10-01

    Mercury concentrations in three flatfish species - flounder (Platichtys flesus), plaice (Pleuronectes platessa), and Baltic turbot (Scophthalmus maximus), netted in the southern Baltic Sea were assessed and compared to concentrations of this metal in sediments, sea water, and flatfish food - bivalve Macoma balthica, isopod Saduria entomon, and sprat (Sprattus sprattus). Collected simultaneously with flatfish in 2009 and 2010. Different concentrations of mercury depending on species, tissue or organ, sex, individual length, kind of food, and region were determined. The muscle tissues of turbot had the highest concentrations of the metal. The bioaccumulation (BF) and biomagnification (BMF) factors has been counted showing that the muscle tissues of turbot have maximum affinity for mercury, and thus best reflected the metal contamination of the Baltic Sea environment. The data suggest that the common Baltic turbot (S. maximus) is an important model species, suitable and cost-effective to biomonitor environmental mercury pollution for ecological research.

  15. Fresh oxygen for the Baltic Sea — An exceptional saline inflow after a decade of stagnation

    NASA Astrophysics Data System (ADS)

    Mohrholz, V.; Naumann, M.; Nausch, G.; Krüger, S.; Gräwe, U.

    2015-08-01

    The ecological state of the Baltic Sea depends crucially on sufficiently frequent, strong deep water renewal on the periodic deep water renewal events by inflow of oxygen rich saline water from the North Sea. Due to the strong density stratification these inflows are the only source for deep water ventilation. Since the early eighties of the last century the frequency of inflow events has dropped drastically from 5 to 7 major inflows per decade to only one inflow per decade. Wide spread anoxic conditions became the usual state in the central Baltic. The rare major Baltic inflow (MBI) events in 1993 and 2003 could interrupt the anoxic bottom conditions only temporarily. After more than 10 years without a major Baltic inflow events, in December 2014 a strong MBI brought large amounts of saline and well oxygenated water into the Baltic Sea. Based on observations and numerical modeling, the inflow was classified as one of the rare very strong events. The inflow volume and the amount of salt transported into the Baltic were estimated to be with 198 km3 and 4 Gt, respectively. The strength of the MBI exceeded considerably the previous 2003 event. In the list of the MBIs since 1880, the 2014 inflow is the third strongest event together with the MBI in 1913. This inflow event will most probably turn the entire Baltic deep water from anoxic to oxic conditions, with substantial spread consequences for marine life and biogeochemical cycles.

  16. Iron cycling microbial communities in sediments of the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Reyes, Carolina; Delwig, Olaf; Noriega-Ortega, Beatriz; Dähnke, Kirstin; Böttcher, Michael E.; Friedrich, Michael W.

    2014-05-01

    The biogeochemical cycling of iron is a key early diagenetic process. However, limited information exists about the diversity and metabolic pathways of microorganisms linked to iron cycling in marine sediments. The goal of this study was to determine the bacterial community diversity in sediments showing ongoing dissimilatory iron reduction using 454-pyrosequencing as a first step in characterizing microorganisms potentially involved in iron reduction. For this purpose, two 35 cm cores were sampled from ferruginous sediments in the Skagerrak (SK) and the Bothnian Bay (BB) from the North-Sea Baltic Sea and the northern Baltic Sea respectively. Pore water profiles showed Fe2+ and Mn2+ levels of ~140-150 µM throughout the core below a 6 cm thick oxidized surface layer in SK sediments and ~300 µM below a 2 cm thick surface layer in BB sediments. Dissolved sulphide levels were below detection in both sediments. No significant depletion of SO42- occurred at both sites, further supported by stable S and O isotope analyses of dissolved sulfate at SK site. Only very minor net sulfate reduction is suggested here from the trend in sulphur isotope signatures, in agreement with previously reported gross microbial sulphate rate measurements (Canfield et al., 1993;GCA). Based on these biogeochemical constraints, Fe reduction in the studied sediments is therefore dominated by microbial dissimilatory iron reduction, while cryptic Fe-S-cycling can be largely excluded. 16S rRNA gene sequences indicate Proteobacteria as the dominating microbial group in these sediments. Potential iron and manganese reducing bacteria included Geobacteraceae, Pelobacteraceae, Shewanellaceae, and Oceanospirillales. Additionally, Actinobacteria and Bacteroidetes were present. Also, Fe-oxidizers were present and their occurrence correlated in depth with a Fe-oxide-rich layer, most likely a former buried Fe-oxidation front. Gene sequences point to the presence of Mariprofundus in SK sediments and

  17. Biogeochemical control of the coupled CO2-O 2 system of the Baltic Sea: a review of the results of Baltic-C.

    PubMed

    Omstedt, Anders; Humborg, Christoph; Pempkowiak, Janusz; Perttilä, Matti; Rutgersson, Anna; Schneider, Bernd; Smith, Benjamin

    2014-02-01

    Past, present, and possible future changes in the Baltic Sea acid-base and oxygen balances were studied using different numerical experiments and a catchment-sea model system in several scenarios including business as usual, medium scenario, and the Baltic Sea Action Plan. New CO2 partial pressure data provided guidance for improving the marine biogeochemical model. Continuous CO2 and nutrient measurements with high temporal resolution helped disentangle the biogeochemical processes. These data and modeling indicate that traditional understandings of the nutrient availability-organic matter production relationship do not necessarily apply to the Baltic Sea. Modeling indicates that increased nutrient loads will not inhibit future Baltic Sea acidification; instead, increased mineralization and biological production will amplify the seasonal surface pH cycle. The direction and magnitude of future pH changes are mainly controlled by atmospheric CO2 concentration. Apart from decreasing pH, we project a decreasing calcium carbonate saturation state and increasing hypoxic area.

  18. The Atmospheric Boundary Layer Over Baltic Sea Ice

    NASA Astrophysics Data System (ADS)

    Brümmer, Burghard; Kirchgäßner, Amèlie; Müller, Gerd

    2005-10-01

    The temporal and spatial variability of the atmospheric boundary layer (ABL) over Baltic Sea ice is presented. The focus is on the properties of the underlying surface (temperature and albedo), the heat fluxes at the air ice/water interface and the vertical ABL structure (inversion layer and low-level jet). The study uses data from two field campaigns, BASIS 1998 and BASIS 2001, applying ice stations, a ship and aircraft over various surface types (land-fast ice, drift ice, and open water). Sensible heat flux ranges from -100 W m-2 under warm-air advection conditions to 300 W m-2 under cold-air advection conditions. On average, it is negative over land-fast ice and positive over open water. An ABL inversion is almost permanently present. It is surface-based 2/3 of the time and extends to 165 m on average. The average base of the elevated inversion is 343 m. The mean temperature increase across all inversions is 2.1 K and is clearly smaller than for Arctic sea-ice inversions. A low-level jet occurs about 86% of the time with an average height of 245 m and speed of 13.3 m s-1, which is 7 m s-1 higher than the surface-layer wind. On average, the low-level jet is located near the top of the surface-based inversion or near the base of the elevated inversion.

  19. Riverine transport of biogenic elements to the Baltic Sea - past and possible future perspectives

    NASA Astrophysics Data System (ADS)

    Humborg, C.; Mörth, C.-M.; Sundbom, M.; Wulff, F.

    2007-09-01

    The paper reviews critical processes for the land-sea fluxes of biogenic elements (C, N, P, Si) in the Baltic Sea catchment and discusses possible future scenarios as a consequence of improved sewage treatment, agricultural practices and increased hydropower demand (for N, P and Si) and of global warming, i.e., changes in hydrological patterns (for C). These most significant drivers will not only change the total amount of nutrient inputs and fluxes of organic and inorganic forms of carbon to the Baltic Sea, their ratio (C:N:P:Si) will alter as well with consequences for phytoplankton species composition in the Baltic Sea. In summary, we propose that N fluxes may increase due to higher livestock densities in those countries recently acceded to the EU, whereas P and Si fluxes may decrease due to an improved sewage treatment in these new EU member states and with further damming and still eutrophic states of many lakes in the entire Baltic Sea catchment. This might eventually decrease cyanobacteria blooms in the Baltic but increase the potential for other nuisance blooms. Dinoflagellates could eventually substitute diatoms that even today grow below their optimal growth conditions due to low Si concentrations in some regions of the Baltic Sea. C fluxes will probably increase from the boreal part of the Baltic Sea catchment due to the expected higher temperatures and heavier rainfall. However, it is not clear whether dissolved organic carbon and alkalinity, which have opposite feedbacks to global warming, will increase in similar amounts, because the spring flow peak will be smoothed out in time due to higher temperatures that cause less snow cover and deeper soil infiltration.

  20. Foraminiferal stable isotope constraints on salinity changes in the deglacial and early Holocene Baltic Sea region

    NASA Astrophysics Data System (ADS)

    Quintana Krupinski, Nadine; Filipsson, Helena; Bokhari-Friberg, Yasmin; Knudsen, Karen-Luise; Mackensen, Andreas; Groeneveld, Jeroen; Austin, William

    2015-04-01

    The northern European Baltic Sea shows evidence of strong coupling with North Atlantic climate over recent glacial-interglacial cycles, but existing climate proxy evidence from regional sediment records suggest that the coupling may occur through non-linear processes. High-resolution regional climate records in Europe and from the Baltic Sea are critical for evaluating this coupling and the regional sensitivity to North Atlantic and global climate signals. However, evaluating the drivers and mechanisms of proposed links between the North Atlantic and Baltic Sea climate has often been hampered by a lack of long, continuous, high-resolution climate records from this area. New high-resolution sediment cores collected by IODP/ECORD Expedition 347 (Baltic Sea Paleoenvironment) allow such records to be generated, including foraminiferal geochemistry records of Baltic Sea hydrographic conditions during the most recent deglaciation and early Holocene (~19-7 cal. ka). The dramatic changes in salinity, sea level, circulation, temperature, and oxygenation during this period, e.g. through massive meltwater release from proglacial lakes and the early Holocene inundation of the Baltic by seawater highlight these non-linear links between the Baltic and North Atlantic. This work uses benthic foraminiferal stable isotope records (δ18O and δ13C) from sites in the western Baltic (M0059, Lillebælt, early Holocene marine stage (Littorina Sea)) and Kattegat (M0060, Anholt, deglaciation) to constrain salinity changes during these intervals. Because of the dramatic changes in salinity this region experiences today and during the study periods, oxygen isotope records (δ18O) here primarily reflect a signal of changing salinity, with a reduced temperature effect. Early δ18O results from the western Baltic (M0059) show a trend of declining δ18O/salinity during the first several kyr of the Littorina Sea stage, in agreement with previous work indicating declining salinity due to gradual

  1. Microsatellite variation in ringed seals (Phoca hispida): genetic structure and history of the Baltic Sea population.

    PubMed

    Palo, J U; Mäkinen, H S; Helle, E; Stenman, O; Väinölä, R

    2001-05-01

    Genetic variability and population structure of Baltic ringed seals and an Arctic reference population were assessed using eight microsatellite loci. Ringed seals colonized the Baltic Sea basin soon after deglaciation 11 500 years ago and are supposed to have remained largely isolated from the main Arctic stock since then, approximately 1000 generations. In the 1900s the Baltic population declined rapidly, and is now confined to three distinct breeding areas, with N < 6000 seals altogether. Microsatellite heterozygosity in ringed seals was higher than that in the closely related, boreal harbour seal and grey seal, for which the markers were initially developed. This is plausibly attributed to an overall greater population (species) size of ringed seals during the Quaternary. Allele frequency differentiation between the Baltic and Arctic ringed seals, conventionally treated as different subspecies, was weak. Assuming complete isolation, the divergence (FST=0.023) would imply a notably high postglacial effective population size, approximately 20 000 for the Baltic population. The isolation assumption however, seems unrealistic in the light of the data: a coalescent-based simulation approach to the likelihood of alternative demographic histories clearly favoured a scenario with recurrent gene flow to the Baltic, over one of complete isolation (drift only). Within the Baltic Sea, no differentiation was found between the Gulf of Finland and the Gulf of Bothnia breeding areas; the recent population decline and split have not yet affected the inbreeding levels of the disjunct breeding stocks. PMID:11554977

  2. An algorithm based on sea level pressure fluctuations to identify major Baltic inflow events

    NASA Astrophysics Data System (ADS)

    Schimanke, Semjon; Dieterich, Christian; Markus Meier, H. E.

    2014-05-01

    The Baltic Sea is one of world largest brackish water areas with an estuarine like circulation. It is connected to the world ocean through the narrow Danish straits limiting the exchange of water masses. The deep water of the Baltic Sea is mainly renewed by so called major Baltic inflows which are an important feature to sustain the sensitive steady state of the Baltic Sea. We introduce an algorithm to identify atmospheric variability favourable for major Baltic inflows. The algorithm is based on sea level pressure fields as the only parameter. Characteristic sea level pressure pattern fluctuations include a precursory phase of 30 days and 10 days of inflow period. The algorithm identifies successfully the majority of observed major Baltic inflows between 1961--2010. In addition, the algorithm finds some occurrences which cannot be related to observed inflows. In these cases with favourable atmospheric conditions inflows were precluded by contemporaneously existing saline water masses or strong freshwater supply. No event is registered during the stagnation period 1983-1993 indicating that the lack of inflows is a consequence of missing favourable atmospheric variability. The only striking inflow which is not identified by the algorithm is the event in January 2003. We demonstrate that this is due to the special evolution of sea level pressure fields which are not comparable with any other event. Finally, the algorithm is applied to an ensemble of scenario simulations. The result indicates that the number of atmospheric events favourable for major Baltic inflows increases slightly in all scenarios. Possible explanations as for instance more frequent atmospheric blockings or changes in the NAO will be discussed.

  3. Upwelling events may cause cyanobacteria blooms in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Wasmund, Norbert; Nausch, Günther; Voss, Maren

    2012-02-01

    Cyanobacteria blooms in the Baltic Sea appear after upwelling events, which transport phosphate-rich intermediate water to the surface. The growth potential of diazotrophic cyanobacteria in upwelled water was studied in a mesocosm (tank) experiment in summer 2007. An Anabaena bloom was only induced in the tanks filled with upwelled surface water but not in those filled with surface water from outside the upwelling cell and with intermediate water. The low initial cyanobacteria biomass in the intermediate water could not grow to bloom concentrations within three weeks. It is concluded that mixing of upwelled water with surrounding surface water forms a precondition for a cyanobacteria bloom. An additional mesocosm experiment conducted in 2009 revealed that mixing of intermediate water with surface water had the same stimulating effect on nitrogen fixation and cyanobacteria growth as artificial phosphate input. Phosphate input stimulates the growth of Nodularia and Anabaena more than that of Aphanizomenon. We suggest that the upwelled phosphate-rich intermediate water has to be mixed with the surface water containing physiologically “young” cyanobacteria biomass of at least 20 mg/m3 as an inoculum in order to initiate a cyanobacteria bloom.

  4. Enrichment of omnivorous cercozoan nanoflagellates from coastal Baltic Sea waters.

    PubMed

    Piwosz, Kasia; Pernthaler, Jakob

    2011-01-01

    Free-living nano-sized flagellates are important bacterivores in aquatic habitats. However, some slightly larger forms can also be omnivorous, i.e., forage upon both bacterial and eukaryotic resources. This hitherto largely ignored feeding mode may have pronounced implications for the interpretation of experiments about protistan bacterivory. We followed the response of an uncultured group of omnivorous cercozoan nanoflagellates from the Novel Clade 2 (Cerc_BAL02) to experimental food web manipulation in samples from the Gulf of Gdańsk (Southern Baltic Sea). Seawater was either prefiltered through 5 µm filters to exclude larger predators of nanoflagellates (F-treatment), or prefiltered and subsequently 1∶10 diluted with sterile seawater (F+D-treatment) to stimulate the growth of both, flagellates and bacteria. Initially, Cerc_BAL02 were rapidly enriched under both conditions. They foraged on both, eukaryotic prey and bacteria, and were highly competitive at low concentrations of food. However, these omnivores were later only successful in the F+D treatment, where they eventually represented almost one fifth of all aplastidic nanoflagellates. By contrast, their numbers stagnated in the F-treatment, possibly due to top-down control by a concomitant bloom of other, unidentified flagellates. In analogy with observations about the enrichment of opportunistically growing bacteria in comparable experimental setups we suggest that the low numbers of omnivorous Cerc_Bal02 flagellates in waters of the Gulf of Gdańsk might also be related to their vulnerability to grazing pressure.

  5. Sea-surface altimetry airborne observations using synoptic GNSS reflectometry at the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Ribó, Serni; Fabra, Fran; Cardellach, Estel; Li, Weiqiang; Rius, Antonio; Praks, Jaan; Rouhe, Erkka; Seppänen, Jaakko; Martín-Neira, Manuel

    2016-04-01

    Recent GNSS-R (Global Navigation Satellite System-Reflections) observations over the Baltic Sea have been taken using the SPIR (Software PARIS Interferometric Receiver) from an airborne platform at 3 km altitude. This newly developed instrument is capable of acquiring GNSS signals transmitted by multiple satellites simultaneously that have been reflected of the sea-surface. Reflections are usually gathered in off-nadir configuration using the instrument's beam-forming capabilities, which results in an increase of the instrument's swath. In this way, this technique opens the door to densify in space and time sea-altimetry observations to enhance future mesoscale and sub-mesoscale ocean altimetry. The altimetric observations collected during the Baltic Sea campaign have been analysed in terms of their power spectral densities. We consider the sequence of observations as an ergodic process that has contributions from the actual true altimetry as well as the observation noise. In this way it is possible to relate the expected ground resolution of the observations with the obtainable altimetric uncertainty. Results will be presented.

  6. Assessment of Marine Mammal Impact Zones for Use of Military Sonar in the Baltic Sea.

    PubMed

    Andersson, Mathias H; Johansson, Torbjörn

    2016-01-01

    Military sonars are known to have caused cetaceans to strand. Navies in shallow seas use different frequencies and sonar pulses, commonly frequencies between 25 and 100 kHz, compared with most studied NATO sonar systems that have been evaluated for their environmental impact. These frequencies match the frequencies of best hearing in the harbor porpoises and seals resident in the Baltic Sea. This study uses published temporary and permanent threshold shifts, measured behavioral response thresholds, technical specifications of a sonar system, and environmental parameters affecting sound propagation common for the Baltic Sea to estimate the impact zones for harbor porpoises and seals.

  7. Assessment of Marine Mammal Impact Zones for Use of Military Sonar in the Baltic Sea.

    PubMed

    Andersson, Mathias H; Johansson, Torbjörn

    2016-01-01

    Military sonars are known to have caused cetaceans to strand. Navies in shallow seas use different frequencies and sonar pulses, commonly frequencies between 25 and 100 kHz, compared with most studied NATO sonar systems that have been evaluated for their environmental impact. These frequencies match the frequencies of best hearing in the harbor porpoises and seals resident in the Baltic Sea. This study uses published temporary and permanent threshold shifts, measured behavioral response thresholds, technical specifications of a sonar system, and environmental parameters affecting sound propagation common for the Baltic Sea to estimate the impact zones for harbor porpoises and seals. PMID:26610942

  8. Metazoan parasites from herring (Clupea harengus L.) as biological indicators in the Baltic Sea.

    PubMed

    Unger, Patrick; Klimpel, Sven; Lang, Thomas; Palm, Harry Wilhelm

    2014-09-01

    Zoographical distribution of metazoan fish parasites in herring, Clupea harengus, from the Baltic Sea was analysed in order to use them as potential biological indicators. A total of 210 herring from six different sampling sites were investigated, harbouring 12 different parasite species [five digeneans (D), one cestode (C), three nematodes (N) and three acanthocephalans (A)]. The distribution of the parasite species differed according to region, with a distinct gradient of decreasing species richness towards the east of the Baltic Sea. The western localities at Kiel Bay, Rügen and Poland had the highest parasite diversity, including the marine parasite species Anisakis simplex (s.s.) (N), Brachyphallus crenatus and Hemiurus luehei (both D). The eastern localities had low parasite species richness, predominated by the freshwater digenean Diplostomum spathaceum. We could identify three different Baltic herring stocks, the spring-spawning herring of the western Baltic reaching from the Kattegat to the German and Polish coast, the stock of the central Baltic proper and the northern stock of C. harengus var. membras of the Gulf of Finland. The limited distribution of the herring parasites within the Baltic Sea enables their use as biological indicators for migration patterns and stock separation. The acanthocephalan Pomphorhynchus laevis that has already been used as an accumulation bioindicator for heavy metals was only recorded for the western herring stocks. However, the presence of mainly generalistic parasites and their uneven distribution patterns make their use as indicators for regional environmental and global change more difficult. PMID:25119368

  9. Metazoan parasites from herring (Clupea harengus L.) as biological indicators in the Baltic Sea.

    PubMed

    Unger, Patrick; Klimpel, Sven; Lang, Thomas; Palm, Harry Wilhelm

    2014-09-01

    Zoographical distribution of metazoan fish parasites in herring, Clupea harengus, from the Baltic Sea was analysed in order to use them as potential biological indicators. A total of 210 herring from six different sampling sites were investigated, harbouring 12 different parasite species [five digeneans (D), one cestode (C), three nematodes (N) and three acanthocephalans (A)]. The distribution of the parasite species differed according to region, with a distinct gradient of decreasing species richness towards the east of the Baltic Sea. The western localities at Kiel Bay, Rügen and Poland had the highest parasite diversity, including the marine parasite species Anisakis simplex (s.s.) (N), Brachyphallus crenatus and Hemiurus luehei (both D). The eastern localities had low parasite species richness, predominated by the freshwater digenean Diplostomum spathaceum. We could identify three different Baltic herring stocks, the spring-spawning herring of the western Baltic reaching from the Kattegat to the German and Polish coast, the stock of the central Baltic proper and the northern stock of C. harengus var. membras of the Gulf of Finland. The limited distribution of the herring parasites within the Baltic Sea enables their use as biological indicators for migration patterns and stock separation. The acanthocephalan Pomphorhynchus laevis that has already been used as an accumulation bioindicator for heavy metals was only recorded for the western herring stocks. However, the presence of mainly generalistic parasites and their uneven distribution patterns make their use as indicators for regional environmental and global change more difficult.

  10. Sources of sedimentary biomarkers and proxies with potential paleoenvironmental significance for the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Kaiser, Jérôme; Arz, Helge W.

    2016-07-01

    The Baltic Sea is a shallow, semi-enclosed and intra-continental shelf sea characterized by anoxic bottom waters in the deepest basins, allowing for the preservation of sedimentary organic matter. In the present study, the most abundant, naturally-occurring lipids in surface sediments from the entire Baltic Sea and the Skagerrak area were identified and their potential sources were assigned. Together with long-chain n-alkanes derived from land plant leaf waxes, diploptene and branched glycerol dialkyl glycerol tetraethers (GDGTs) are of allochthonous origin, while isoprenoid GDGTs, hydroxylated isoprenoid GDGTs (OH-GDGTs), n-C25:1, n-C27:1 and n-C29:1 alkenes are autochthonous lipids. The isoprenoid and OH-GDGTs are probably derived from Thaumarchaeota and the long-chain n-alkenes from phototrophic organisms. Significant correlations were found between indexes based on isoprenoid and OH-GDGTs and Baltic Sea surface and bottom temperatures. The calibrations obtained for surface temperature have statistically similar slopes, but different intercepts than calibrations established for the Nordic Seas. The branched and isoprenoid tetraether index can be used to estimate the percentage of soil (terrestrial) organic matter in the sediments of the Baltic Sea. High values of the Paq' ratio (defined here as the ratio of odd numbered n-C23 and n-C25 over n-C23 to n-C29 alkanes) in the northern Baltic Sea originate from the presence of both Sphagnum mosses in the drainage basin and submerged macrophytes, such as Potamogeton sp. and Myriophyllum sp., in the freshwater to brackish water of the coastal areas. The Paq' ratio may thus reflect fluctuations in the regional expansion of freshwater to brackish coastal environments in the Baltic Sea.

  11. Biodiversity gradient in the Baltic Sea: a comprehensive inventory of macrozoobenthos data

    NASA Astrophysics Data System (ADS)

    Zettler, Michael L.; Karlsson, Anna; Kontula, Tytti; Gruszka, Piotr; Laine, Ari O.; Herkül, Kristjan; Schiele, Kerstin S.; Maximov, Alexey; Haldin, Jannica

    2014-03-01

    In the Helsinki Commission Red List project 2009-2012, taxonomic and distributional data of benthic (macro) invertebrates were compiled by the present authors in a comprehensive checklist of the Baltic Sea fauna. Based on the most recent and comprehensive data, this paper presents the diversity patterns observed among benthic invertebrates in the Baltic Sea. As expected, the total number of species per sub-region generally declined along the salinity gradient from the Danish Straits to the northern Baltic Sea. This relationship is well known from the Baltic Sea and has resulted in a general assumption of an exponentially positive relationship between species richness and salinity for marine species, and a negative relationship for freshwater species. In 1934, Remane produced a diagram to describe the hypothetical distribution of benthic invertebrate diversity along a marine-freshwater salinity gradient. Our results clearly indicated the validity of this theory for the macrozoobenthic diversity pattern within the Baltic Sea. Categorisation of sub-regions according to species composition showed both separation and grouping of some sub-regions and a strong alignment of similarity patterns of zoobenthic species composition along the salinity gradient.

  12. Anthropogenic and naturally produced brominated substances in Baltic herring (Clupea harengus membras) from two sites in the Baltic Sea.

    PubMed

    Dahlberg, Anna-Karin; Bignert, Anders; Legradi, Jessica; Legler, Juliette; Asplund, Lillemor

    2016-02-01

    In the eutrophicated Baltic Sea, several naturally produced hydroxylated polybrominated diphenyl ethers (OH-PBDEs) have been found in marine biota. OH-PBDEs are toxic to adult and developing zebrafish and shown to be potent disruptors of oxidative phosphorylation (OXPHOS). Disturbed OXPHOS can result in altered energy metabolism and weight loss. In herring, the concentration of OH-PBDEs (i.e. 2'-OH-BDE68 and 6-OH-BDE47) has increased during the period 1980-2010 in the Baltic Proper. Over the same time period, the condition and fat content in Baltic herring have decreased. Given the toxicity and increasing trends of OH-PBDEs in Baltic herring it is important to further assess the exposure to OH-PBDEs in Baltic herring. In this study, the concentrations of OH-PBDEs and related brominated substances i.e. polybrominated phenols (PBPs), polybrominated anisoles (PBAs), methoxylated polybrominated diphenyl ethers (MeO-PBDEs) and polybrominated diphenyl ethers (PBDEs) were measured in herring sampled in the northern Baltic Proper (Askö, n = 12) and the southern Bothnian Sea (Ängskärsklubb, n = 12). The geometric mean (GM) concentrations (ng/g l.w.) at Askö and Ängskärsklubb were; Σ2PBPs: 4.3 and 9.6, Σ(2)PBAs: 34 and 20, Σ(6)OH-PBDEs: 9.4 and 10, Σ(7)MeO-PBDEs: 42 and 150, Σ(6)PBDEs: 54 and 27, respectively. 6-OH-BDE47 dominated the OH-PBDE profile and comprised 87% (Askö) and 91% (Ängskärsklubb) of the ΣOH-PBDEs. At Ängskärsklubb the mean concentration of ΣMeO-PBDEs (150 ng/g l.w.) was 15 times higher than ΣOH-PBDEs. As other fish species are known to metabolically transform MeO-PBDEs to OH-PBDEs, high levels of MeO-PBDEs can be of concern as a precursor for more toxic OH-PBDEs in herring and their roe. PMID:26613358

  13. Anthropogenic and naturally produced brominated substances in Baltic herring (Clupea harengus membras) from two sites in the Baltic Sea.

    PubMed

    Dahlberg, Anna-Karin; Bignert, Anders; Legradi, Jessica; Legler, Juliette; Asplund, Lillemor

    2016-02-01

    In the eutrophicated Baltic Sea, several naturally produced hydroxylated polybrominated diphenyl ethers (OH-PBDEs) have been found in marine biota. OH-PBDEs are toxic to adult and developing zebrafish and shown to be potent disruptors of oxidative phosphorylation (OXPHOS). Disturbed OXPHOS can result in altered energy metabolism and weight loss. In herring, the concentration of OH-PBDEs (i.e. 2'-OH-BDE68 and 6-OH-BDE47) has increased during the period 1980-2010 in the Baltic Proper. Over the same time period, the condition and fat content in Baltic herring have decreased. Given the toxicity and increasing trends of OH-PBDEs in Baltic herring it is important to further assess the exposure to OH-PBDEs in Baltic herring. In this study, the concentrations of OH-PBDEs and related brominated substances i.e. polybrominated phenols (PBPs), polybrominated anisoles (PBAs), methoxylated polybrominated diphenyl ethers (MeO-PBDEs) and polybrominated diphenyl ethers (PBDEs) were measured in herring sampled in the northern Baltic Proper (Askö, n = 12) and the southern Bothnian Sea (Ängskärsklubb, n = 12). The geometric mean (GM) concentrations (ng/g l.w.) at Askö and Ängskärsklubb were; Σ2PBPs: 4.3 and 9.6, Σ(2)PBAs: 34 and 20, Σ(6)OH-PBDEs: 9.4 and 10, Σ(7)MeO-PBDEs: 42 and 150, Σ(6)PBDEs: 54 and 27, respectively. 6-OH-BDE47 dominated the OH-PBDE profile and comprised 87% (Askö) and 91% (Ängskärsklubb) of the ΣOH-PBDEs. At Ängskärsklubb the mean concentration of ΣMeO-PBDEs (150 ng/g l.w.) was 15 times higher than ΣOH-PBDEs. As other fish species are known to metabolically transform MeO-PBDEs to OH-PBDEs, high levels of MeO-PBDEs can be of concern as a precursor for more toxic OH-PBDEs in herring and their roe.

  14. Mean and extreme sea level changes in the southwestern Baltic Sea

    NASA Astrophysics Data System (ADS)

    Schmidt, Jessica; Patzke, Justus; Dangendorf, Sönke; Arns, Arne; Jensen, Jürgen; Fröhle, Peter

    2016-04-01

    In this contribution an overview over the BMBF project AMSeL_Ostsee (2015-2018) for the assessment of mean and extreme sea level changes over the past 150 years in the southwestern Baltic Sea is presented. We compile several high resolution tide gauge records provided by the Water and Shipping Administration (WSV) along the German Baltic Sea coastline and merge them in internationally available data bases (UHSLC, PSMSL, and data officially available at national authorities). In addition, we make efforts in digitizing historical records to expand the number of available data sets in this complex and vulnerable coastal region. To separate absolute from relative long-term changes in sea level the vertical land motion (VLM) at specific sites is assessed. Possible sources of VLM are independently assessed by using different state-of-the-art approaches, that is: Glacial Isostatic Adjustment (GIA) modelled by viscoelastic Earth models, GPS derived VLM, and the difference between tide gauge and nearby satellite altimetry. The VLM corrected tide gauge records are further assessed for linear and non-linear trends as well as possible acceleration/deceleration patterns by applying advanced time series models such as Singular System Analysis (SSA) combined with a Monte-Carlo-Autoregressive-Padding approach (Wahl et al., 2010). These trend assessments are applied to mean and extreme sea levels independently to prove whether observed changes in extremes are either due to an underlying trend on mean sea levels or changes in storminess. References: Wahl, T., Jensen, J., Frank, T. (2011): On analysing sea level rise in the German Bight since 1844, NHESS, 10, 171-179.

  15. Influence of the arrival of radioactive industrially contaminated North Sea water upon the radiation conditions in the Baltic Sea

    SciTech Connect

    Vakulovskii, S.M.; Nikitin, A.I.; Chumichev, V.B.

    1987-08-01

    The authors present and evaluate data from a four-year period of monitoring the movement of radioactive effluents from the radiochemical plants of Western Europe from the North Sea to the Baltic Sea and determine the concentrations at various regions along this pathway for cesium 134 and 137 and strontium 90 isotopes.

  16. Modelling the Baltic Sea ocean climate on centennial time scale: temperature and sea ice

    NASA Astrophysics Data System (ADS)

    Hansson, Daniel; Omstedt, Anders

    2008-06-01

    This study considers the possible use of different kinds of forcing datasets in Baltic Sea ocean climate modelling on centennial time scales, in particular for the past half millennium. We demonstrate that high-quality station data of the past century and gridded multi-proxy reconstructions for the past 500 years can be used with great success but with various levels of detail. We also demonstrate that output data from the state-of-the-art global climate model EcHo-G are not suitable for modelling the Baltic Sea ocean climate. Two climate properties were studied: the annual maximum ice extent (MIB) and the vertically and horizontally integrated annual water temperature. Centennial time scale results indicate that the seventeenth and nineteenth centuries were the coldest centuries, while the 1690s were the coldest decade and 1695 the coldest year in the last 500 years. The results also indicate that the twentieth century was the warmest century with the least MIB of the last 500 years. On a decadal time scale, the 1990s, 1930s and 1730s were the warmest decades and comparable in terms of both water temperature and MIB. The year 1989 had the minimum observed MIB of only 52,000 km2, implying that the Baltic Sea has been partly ice covered in all winters of the past half millennium. Even though different climate forcing mechanisms may operate on the climate system today compared to over the last half millennium, this study cannot clearly state that the region is experiencing climate change outside the natural limits of the past 500 years.

  17. Transplant experiments uncover Baltic Sea basin-specific responses in bacterioplankton community composition and metabolic activities.

    PubMed

    Lindh, Markus V; Figueroa, Daniela; Sjöstedt, Johanna; Baltar, Federico; Lundin, Daniel; Andersson, Agneta; Legrand, Catherine; Pinhassi, Jarone

    2015-01-01

    Anthropogenically induced changes in precipitation are projected to generate increased river runoff to semi-enclosed seas, increasing loads of terrestrial dissolved organic matter and decreasing salinity. To determine how bacterial community structure and functioning adjust to such changes, we designed microcosm transplant experiments with Baltic Proper (salinity 7.2) and Bothnian Sea (salinity 3.6) water. Baltic Proper bacteria generally reached higher abundances than Bothnian Sea bacteria in both Baltic Proper and Bothnian Sea water, indicating higher adaptability. Moreover, Baltic Proper bacteria growing in Bothnian Sea water consistently showed highest bacterial production and beta-glucosidase activity. These metabolic responses were accompanied by basin-specific changes in bacterial community structure. For example, Baltic Proper Pseudomonas and Limnobacter populations increased markedly in relative abundance in Bothnian Sea water, indicating a replacement effect. In contrast, Roseobacter and Rheinheimera populations were stable or increased in abundance when challenged by either of the waters, indicating an adjustment effect. Transplants to Bothnian Sea water triggered the initial emergence of particular Burkholderiaceae populations, and transplants to Baltic Proper water triggered Alteromonadaceae populations. Notably, in the subsequent re-transplant experiment, a priming effect resulted in further increases to dominance of these populations. Correlated changes in community composition and metabolic activity were observed only in the transplant experiment and only at relatively high phylogenetic resolution. This suggested an importance of successional progression for interpreting relationships between bacterial community composition and functioning. We infer that priming effects on bacterial community structure by natural episodic events or climate change induced forcing could translate into long-term changes in bacterial ecosystem process rates. PMID

  18. Comparison of nematode communities in Baltic and North Sea sublittoral, permeable sands Diversity and environmental control

    NASA Astrophysics Data System (ADS)

    Urban-Malinga, Barbara; Hedtkamp, Stefanie I. C.; van Beusekom, Justus E. E.; Wiktor, Józef; Węsławski, Jan Marcin

    2006-10-01

    The structure of free-living nematode communities was investigated seasonally at two sandy locations representing typical shallow sublittoral, permeable environments of the North Sea and the Baltic Sea. At the Baltic study site the chlorophyll and organic carbon concentrations in the sediment were, on average, four times lower than at the North Sea. Highest nematode densities (1674-4100 ind. 10 cm -2) and a higher number of free-living nematode genera (66) were recorded in the North Sea (Baltic: 206-1227 ind. 10 cm -2, 30 genera). Despite lower salinity and lower food availability the less dense and less diverse Baltic nematode community was similar in generic composition to the North Sea community. At the North Sea site, all trophic groups according to Wieser's classification were present with omnivores/predators, dominated by Viscosia, prevailing and followed by epistrate-feeders. In the food-limited Baltic community, non-selective deposit feeders (mainly Ascolaimus, Axonolaimus and Daptonema) and omnivores/predators dominated by Enoplolaimus were the most abundant trophic groups while selective deposit feeders were absent or their contribution was negligible. An analysis of the vertical generic distribution revealed highest diversity of the Baltic community in deeper sediment layers, below the sediment surface affected by ripple migration and near the interface of oxic and anoxic conditions. The diversity pattern in the North Sea sediment was more variable but generally showed high diversity in the upper centimetre of the sediment. These observations suggest that food supply and sediment oxygenation are the most important factors influencing the vertical pattern of nematode generic diversity in sublittoral, permeable sands.

  19. Unstructured-grid model for the North Sea and Baltic Sea: Validation against observations

    NASA Astrophysics Data System (ADS)

    Zhang, Yinglong J.; Stanev, E. V.; Grashorn, S.

    2016-01-01

    A new unstructured-grid model and its application to the North Sea and Baltic Sea are described. The research focus is on the dynamics in the two basins and in the multiple straits connecting them and more specifically on how the model replicates the temporal and spatial variability of physical processes. The comparison against observed data indicates the realism in the simulations of the exchange flows. The simulations demonstrated that in contrast to the tidal variability which decreases in the strait, the role of the barotropic forcing due to weather systems increases. In this zone reversal of transport is well manifested by the increased difference between the surface and bottom salinity values. Small sub-basins like Arkona and Bornholm play the role of reservoirs for denser water which under specific conditions cascades on its way to the Gotland Deep. Unlike the intermediate and deep water salinity in the Baltic Sea, which is strongly affected by fluxes in the straits, the simulated winter-refill and evolution of cold intermediate water are rather driven by surface cooling and processes in the upper mixed layer.

  20. Pyrolysis-gas chromatography-mass spectrometry with electron-ionization or resonance-enhanced-multi-photon-ionization for characterization of polycyclic aromatic hydrocarbons in the Baltic Sea.

    PubMed

    Otto, Stefan; Streibel, Thorsten; Erdmann, Sabrina; Klingbeil, Sophie; Schulz-Bull, Detlef; Zimmermann, Ralf

    2015-10-15

    Polycyclic aromatic hydrocarbons (PAH), as a part of dissolved organic matter (DOM), are environmental pollutants of the marine compartment. This study investigates the origin of PAH, which is supposed to derive mainly from anthropogenic activities, and their alteration along the salinity gradient of the Baltic Sea. Pyrolysis in combination with gas chromatography and two mass selective detectors in one measurement cycle are utilized as a tool for an efficient trace analysis of such complex samples, by which it is possible to detect degradation products of high molecular structures. Along the north-south transect of the Baltic Sea a slightly rising trend for PAH is visible. Their concentration profiles correspond to the ship traffic as a known anthropogenic source, underlined by the value of special isomer ratios such as phenanthrene and anthracene (0.31-0.45) or pyrene and fluoranthene (0.44-0.53). The detection of naphthalene and the distribution of its alkylated representatives support this statement.

  1. Pyrolysis-gas chromatography-mass spectrometry with electron-ionization or resonance-enhanced-multi-photon-ionization for characterization of polycyclic aromatic hydrocarbons in the Baltic Sea.

    PubMed

    Otto, Stefan; Streibel, Thorsten; Erdmann, Sabrina; Klingbeil, Sophie; Schulz-Bull, Detlef; Zimmermann, Ralf

    2015-10-15

    Polycyclic aromatic hydrocarbons (PAH), as a part of dissolved organic matter (DOM), are environmental pollutants of the marine compartment. This study investigates the origin of PAH, which is supposed to derive mainly from anthropogenic activities, and their alteration along the salinity gradient of the Baltic Sea. Pyrolysis in combination with gas chromatography and two mass selective detectors in one measurement cycle are utilized as a tool for an efficient trace analysis of such complex samples, by which it is possible to detect degradation products of high molecular structures. Along the north-south transect of the Baltic Sea a slightly rising trend for PAH is visible. Their concentration profiles correspond to the ship traffic as a known anthropogenic source, underlined by the value of special isomer ratios such as phenanthrene and anthracene (0.31-0.45) or pyrene and fluoranthene (0.44-0.53). The detection of naphthalene and the distribution of its alkylated representatives support this statement. PMID:26277803

  2. Oceanographic connectivity and environmental correlates of genetic structuring in Atlantic herring in the Baltic Sea.

    PubMed

    Teacher, Amber Gf; André, Carl; Jonsson, Per R; Merilä, Juha

    2013-04-01

    Marine fish often show little genetic structuring in neutral marker genes, and Atlantic herring (Clupea harengus) in the Baltic Sea are no exception; historically, very low levels of population differentiation (F ST ≍ 0.002) have been found, despite a high degree of interpopulation environmental heterogeneity in salinity and temperature. Recent exome sequencing and SNP studies have however shown that many loci are under selection in this system. Here, we combined population genetic analyses of a large number of transcriptome-derived microsatellite markers with oceanographic modelling to investigate genetic differentiation and connectivity in Atlantic herring at a relatively fine scale within the Baltic Sea. We found evidence for weak but robust and significant genetic structuring (F ST = 0.008) explainable by oceanographic connectivity. Genetic differentiation was also associated with site differences in temperature and salinity, with the result driven by the locus Her14 which appears to be under directional selection (F ST = 0.08). The results show that Baltic herring are genetically structured within the Baltic Sea, and highlight the role of oceanography and environmental factors in explaining this structuring. The results also have implications for the management of herring fisheries, the most economically important fishery in the Baltic Sea, suggesting that the current fisheries management units may be in need of revision.

  3. The native bacterioplankton community in the central baltic sea is influenced by freshwater bacterial species.

    PubMed

    Riemann, L; Leitet, C; Pommier, T; Simu, K; Holmfeldt, K; Larsson, U; Hagström, A

    2008-01-01

    The Baltic Sea is one of the largest brackish environments on Earth. Despite extensive knowledge about food web interactions and pelagic ecosystem functioning, information about the bacterial community composition in the Baltic Sea is scarce. We hypothesized that due to the eutrophic low-salinity environment and the long water residence time (>5 years), the bacterioplankton community from the Baltic proper shows a native "brackish" composition influenced by both freshwater and marine phylotypes. The bacterial community composition in surface water (3-m depth) was examined at a single station throughout a full year. Denaturing gradient gel electrophoresis (DGGE) showed that the community composition changed over the year. Further, it indicated that at the four extensive samplings (16S rRNA gene clone libraries and bacterial isolates from low- and high-nutrient agar plates and seawater cultures), different bacterial assemblages associated with different environmental conditions were present. Overall, the sequencing of 26 DGGE bands, 160 clones, 209 plate isolates, and 9 dilution culture isolates showed that the bacterial assemblage in surface waters of the central Baltic Sea was dominated by Bacteroidetes but exhibited a pronounced influence of typical freshwater phylogenetic groups within Actinobacteria, Verrucomicrobia, and Betaproteobacteria and a lack of typical marine taxa. This first comprehensive analysis of bacterial community composition in the central Baltic Sea points to the existence of an autochthonous estuarine community uniquely adapted to the environmental conditions prevailing in this brackish environment.

  4. Impact of climate change on fish population dynamics in the Baltic sea: a dynamical downscaling investigation.

    PubMed

    Mackenzie, Brian R; Meier, H E Markus; Lindegren, Martin; Neuenfeldt, Stefan; Eero, Margit; Blenckner, Thorsten; Tomczak, Maciej T; Niiranen, Susa

    2012-09-01

    Understanding how climate change, exploitation and eutrophication will affect populations and ecosystems of the Baltic Sea can be facilitated with models which realistically combine these forcings into common frameworks. Here, we evaluate sensitivity of fish recruitment and population dynamics to past and future environmental forcings provided by three ocean-biogeochemical models of the Baltic Sea. Modeled temperature explained nearly as much variability in reproductive success of sprat (Sprattus sprattus; Clupeidae) as measured temperatures during 1973-2005, and both the spawner biomass and the temperature have influenced recruitment for at least 50 years. The three Baltic Sea models estimate relatively similar developments (increases) in biomass and fishery yield during twenty-first century climate change (ca. 28 % range among models). However, this uncertainty is exceeded by the one associated with the fish population model, and by the source of global climate data used by regional models. Knowledge of processes and biases could reduce these uncertainties.

  5. Mass variations of the Baltic Sea compared to superconducting gravimeter and GRACE

    NASA Astrophysics Data System (ADS)

    Virtanen, H.; Virtanen, J.; Nordman, M.; Bilker-Koivula, M.; Mäkinen, J.

    2009-04-01

    We study the gravity effect of Baltic Sea mass variations observed using different methods and time resolutions. We compare data from tide gauges, from superconductive gravimeter (SG) at Metsähovi, Finland and from the GRACE gravity satellite. The mass variation in the semi-enclosed Baltic Sea is due to both internal redistribution of the water mass and due to changes in the so-called fill level caused by water exchange with the North Sea. The monthly variation in the water mass is about 60 Gt over an area of 390000 km-2. Due to a dense network of tide gauges, the Baltic Sea is one of best monitored mass variations in this size in the world. For modeling the observed water mass, we have used both monthly PSMSL tide gauge records and hourly values from several sources. In addition, we have hydrodynamic models for comparisons. To calculate gravity effect, we have used Green's function formalism for modeled sea surface. We have previously used temporal gravity field data from GRACE satellite to show that GRACE can recover the total mass variation in the Baltic Sea on monthly scales. In addition to monthly GRACE solutions with different filters, we now also use 10-day mascon block solutions from Goddard Space Flight Center. As the GRACE solutions are already corrected for gravity changes due to oceans, we have restored the contribution due to the Baltic Sea. We have also corrected for an effect due to leakage of continental water storage using the GLDAS hydrology model. The fundamental station Metsähovi is located 10 km from the nearest bay of the Baltic Sea and 15 km from the open sea. Using a single tide gauge at the distance of 30 km from SG at Metsähovi, very clear correlation is found between gravity and sea level. Superconducting gravity data has been corrected by tides and polar motion, atmospheric mass redistribution, local groundwater and drift. Hourly mass variations of sea are clearly separable. Theoretically one-meter even-layer water cause 30 nms-2

  6. Caesium-137 distribution, inventories and accumulation history in the Baltic Sea sediments.

    PubMed

    Zaborska, Agata; Winogradow, Aleksandra; Pempkowiak, Janusz

    2014-01-01

    The Baltic Sea is susceptible to pollution by hazardous substances due to limited water exchange, shallowness, and the large catchment area. Radionuclides, particularly (137)Cs, are one of the most hazardous anthropogenic substances present in the Baltic environment. This study was conducted to present (137)Cs present contamination that should further be a subject of reliable monitoring when the new Nuclear Power Plant is put into operation in the northern Poland. The sea-wide, up to date distribution of (137)Cs activities and inventories in the Baltic Sea bottom sediments are presented. The (137)Cs activity concentrations were measured in 30 cm long sediment cores collected at 22 sampling stations. Sediment accumulation rates were quantified by (210)Pb geochronology to follow the history of (137)Cs accumulation. The (137)Cs inventories and fluxes were calculated. Most of the Baltic Sea sediments accumulated (137)Cs in the range from 750 to 2675 Bq m(-2). The Bothnian Bay is severely contaminated by (137)Cs with inventories up to 95,191 Bq m(-2). This region is moreover characterized by extremely large patchiness of (137)Cs inventories. The (137)Cs annual fluxes are highest at the two stations located at the Bothnian Bay (342 Bq m(-2) and 527 Bq m(-2)) due to large Chernobyl (137)Cs contamination of that region and high sediment accumulation rates. When these stations are excluded, the recent, annual mean value of (137)Cs load to the Baltic Sea deposits is 38 ± 22 Bq m(-2). The distribution of radio-caesium inventories over the Baltic Sea nowadays reflects the pattern of Chernobyl contamination. The radio-caesium deposited in surface sediments is not permanently buried, but may be resuspended and redeposited by currents, bioturbation or anthropogenic activities.

  7. Egg production of turbot, Scophthalmus maximus, in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Nissling, Anders; Florin, Ann-Britt; Thorsen, Anders; Bergström, Ulf

    2013-11-01

    In the brackish water Baltic Sea turbot spawn at ~ 6-9 psu along the coast and on offshore banks in ICES SD 24-29, with salinity influencing the reproductive success. The potential fecundity (the stock of vitellogenic oocytes in the pre-spawning ovary), egg size (diameter and dry weight of artificially fertilized 1-day-old eggs) and gonad dry weight were assessed for fish sampled in SD 25 and SD 28. Multiple regression analysis identified somatic weight, or total length in combination with Fulton's condition factor, as main predictors of fecundity and gonad dry weight with stage of maturity (oocyte packing density or leading cohort) as an additional predictor. For egg size, somatic weight was identified as main predictor while otolith weight (proxy for age) was an additional predictor. Univariate analysis using GLM revealed significantly higher fecundity and gonad dry weight for turbot from SD 28 (3378-3474 oocytes/g somatic weight) compared to those from SD 25 (2343 oocytes/g somatic weight), with no difference in egg size (1.05 ± 0.03 mm diameter and 46.8 ± 6.5 μg dry weight; mean ± sd). The difference in egg production matched egg survival probabilities in relation to salinity conditions suggesting selection for higher fecundity as a consequence of poorer reproductive success at lower salinities. This supports the hypothesis of higher size-specific fecundity towards the limit of the distribution of a species as an adaptation to harsher environmental conditions and lower offspring survival probabilities. Within SD 28 comparisons were made between two major fishing areas targeting spawning aggregations and a marine protected area without fishing. The outcome was inconclusive and is discussed with respect to potential fishery induced effects, effects of the salinity gradient, effects of specific year-classes, and effects of maturation status of sampled fish.

  8. Seabird Guano Fertilizes Baltic Sea Littoral Food Webs

    PubMed Central

    Gagnon, Karine; Rothäusler, Eva; Syrjänen, Anneli; Yli-Renko, Maria; Jormalainen, Veijo

    2013-01-01

    Nutrient enrichment in coastal marine systems can have profound impacts on trophic networks. In the Baltic Sea, the population of Great Cormorant (Phalacrocorax carbo sinensis) has increased nearly exponentially since the mid-1990s, and colonies of these seabirds can be important sources of nitrogen enrichment for nearby benthic communities due to guano runoff. In this study we used stable isotope analyses and diet mixing models to determine the extent of nitrogen enrichment from cormorant colonies, as well as to examine any possible changes in herbivore diet preferences due to enrichment. We found significantly higher levels of δ15N in samples from colony islands than control islands for producers (the dominant macroalga Fucus vesiculosus, filamentous algae, and periphyton) and herbivores, as well as a positive correlation between enrichment and nest density in colony sites. We also found that enrichment increased over the breeding season of the cormorants, with higher enrichment in late summer than early summer. While the amount of total nitrogen did not differ between colony and control sites, the amount of guano-based nitrogen in algae was >50% in most sites, indicating high nitrogen enrichment from colonies. Herbivores (the isopod Idotea balthica and the gastropod Theodoxus fluviatilis) preferred feeding upon the dominant macroalga Fucus vesiculosus rather than on filamentous algae or periphyton in both control and colony, and there was a significant increase in periphyton consumption near colony sites. Overall, guano from cormorant colonies seems to have effects on both producers and herbivores, as well as the potential to modify algae-herbivore interactions. PMID:23593452

  9. Freak waves in Tallinn Bay, the Baltic sea

    NASA Astrophysics Data System (ADS)

    Didenkulova, I.; Kurennoy, D.; Soomere, T.

    2009-04-01

    We discuss freak wave events recorded in Tallinn Bay, Baltic Sea, in relatively low overall wave conditions. High resolution time series of water surface elevations collected using an ultrasonic echosounder LOG_aLevel® from General Acoustics. The measurement range of the sensor was 0.5-10 m to the water surface with an accuracy of ±1 mm. The surface water elevation data were collected almost continuously over 30 days (21 June - 20 July 2008) at a recording frequency of 5 Hz. The device was mounted at distance of about 100 m offshore from an effectively non-reflecting shore of the island of Aegna at a depth of ~2.7 m. A part of the experiment was performed in almost calm conditions (significant wave height below 10 cm). The typical significant wave height was 30 cm and reached 60-70 cm during short time intervals. The analysis of the record revealed several unexpectedly high and steep waves with periods close to the typical periods of the windseas. The most prominent freak wave event was recorded on July 9, 2008 when the significant wave height was about 40 cm and the peak period about 4 s. The height and period of the wave were 1.2 m and 5 s, respectively. The height of the freak wave therefore about 3 times exceeded the significant wave height. The wave arrived without any warning or "hole" ahead of it; instead, it was followed by a deep trough (about 40 cm). The wave was highly asymmetric: its crest reached over 80 cm whereas the typical crest elevation was below 20 cm. We also present several other examples of freak waves, analyze wind wave statistics in June-July 2008, and discuss the distribution functions of wave characteristics.

  10. Seabird guano fertilizes Baltic Sea littoral food webs.

    PubMed

    Gagnon, Karine; Rothäusler, Eva; Syrjänen, Anneli; Yli-Renko, Maria; Jormalainen, Veijo

    2013-01-01

    Nutrient enrichment in coastal marine systems can have profound impacts on trophic networks. In the Baltic Sea, the population of Great Cormorant (Phalacrocorax carbo sinensis) has increased nearly exponentially since the mid-1990 s, and colonies of these seabirds can be important sources of nitrogen enrichment for nearby benthic communities due to guano runoff. In this study we used stable isotope analyses and diet mixing models to determine the extent of nitrogen enrichment from cormorant colonies, as well as to examine any possible changes in herbivore diet preferences due to enrichment. We found significantly higher levels of δ(15)N in samples from colony islands than control islands for producers (the dominant macroalga Fucus vesiculosus, filamentous algae, and periphyton) and herbivores, as well as a positive correlation between enrichment and nest density in colony sites. We also found that enrichment increased over the breeding season of the cormorants, with higher enrichment in late summer than early summer. While the amount of total nitrogen did not differ between colony and control sites, the amount of guano-based nitrogen in algae was >50% in most sites, indicating high nitrogen enrichment from colonies. Herbivores (the isopod Idotea balthica and the gastropod Theodoxus fluviatilis) preferred feeding upon the dominant macroalga Fucus vesiculosus rather than on filamentous algae or periphyton in both control and colony, and there was a significant increase in periphyton consumption near colony sites. Overall, guano from cormorant colonies seems to have effects on both producers and herbivores, as well as the potential to modify algae-herbivore interactions. PMID:23593452

  11. Prospects of the New Science and Outreach Network Baltic Earth with Results of the Second Climate Change Assessment for the Baltic Sea Region (BACC II)

    NASA Astrophysics Data System (ADS)

    Reckermann, M.; Von Storch, H.; Omstedt, A. T.; Meier, M.; Rutgersson, A.

    2014-12-01

    The Baltic Sea region in Northern Europe spans different climate and population zones, from a temperate, highly populated, industrialized south with intensive agriculture to a boreal, rural north. It represents an old cultural landscape, and the Baltic Sea itself is among the most intensively studied sea areas of the world. Baltic Earth is the new Earth system research network for the Baltic Sea region. It is the successor to BALTEX, which was terminated in June 2013 after 20 years and two successful phases. Baltic Earth stands for the vision to achieve an improved Earth system understanding of the Baltic Sea region. This means that the research disciplines of BALTEX continue to be relevant, i.e. atmospheric and climate sciences, hydrology, oceanography and biogeochemistry, but a more holistic view of the Earth system encompassing processes in the atmosphere, on land and in the sea as well as in the anthroposphere shall gain in importance in Baltic Earth. Specific grand research challenges have been formulated, representing interdisciplinary research questions to be tackled in the coming years. A major means will be scientific assessments of particular research topics by expert groups, similar to the BACC approach, which shall help to identify knowledge gaps and develop research strategies. A major outcome of Baltic Earth will be the update of the BALTEX Assessment of Climate Change for the Baltic Sea Basin (BACC II). This new study after 5 years finds the results of BACC I still valid. Climate change can be detected at the regional scale but attribution is still weak. The effect of changing atmospheric aerosol loads and land use change is largely unknown so far and needs further attention in the coming years. For the observed changes in biogeochemical and ecological systems, multiple drivers are at work of which climate change is one. Their relative importance still needs to be evaluated. When addressing climate change impacts on e.g. forestry, agriculture, urban

  12. Bacterial sulfate reduction and methanogenesis in brackish, oligotrophic northern Baltic Sea sediments

    NASA Astrophysics Data System (ADS)

    Brüchert, Volker; Nguyen, Thang M.; Deutschmann, André; Böttcher, Michael E.; Ferdelman, Timothy G.

    2010-05-01

    Recent sediments of the northernmost Baltic Sea form underneath low-phosphate surface waters with year-round low primary production. Terrestrial organic matter from subarctic peatlands and tundra are important sources of organic matter in these sediments. These conditions make the northern Baltic an attractive Baltic analog of the Arctic shelf, because effects of changes in weathering patterns on land due to climate-related changes in temperature and runoff can be more easily studied in these sediments. Due to low production and salinities below 4 permil of northern Baltic Sea seawater, organic matter mineralization in these sediments has traditionally been thought to be dominated by aerobic respiration and suboxic diagenesis via bacterial denitrification, manganese, and iron reduction. Here we show with porewater water analyses of sulfate and methane as well as direct rate measurements of bacterial sulfate reduction and methanogenesis that these processes are more important for organic matter mineralization in these sediments than previously thought. Methane concentrations in porewaters reach saturation only few decimeters below the sediment surface and attest to the steep concentration profiles of sulfate driven by high rates of bacterial sulfate reduction. Anaerobic carbon mineralization and methane formation, and upward transport of methane to the sediment surface and water column are therefore significant components of Northern Baltic Sea sediment biogeochemistry.

  13. Loading effects in Metsähovi from the atmosphere and the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Virtanen, Heikki

    2004-10-01

    Loading by atmosphere and by the Baltic Sea cause gravity change at Metsähovi, located 15 km from the open sea. Gravity is changed by both the Newtonian attraction of the loading mass and by the crustal deformation. We have performed loading calculations using appropriate Green's function for both gravity and deformation, for both atmospheric and Baltic loading. The loading by atmosphere has been computed using a detailed surface pressure field from high resolution limited area model (HIRLAM) for north Europe up to 10° distances. Baltic Sea level is modelled using tide gauge records. Calculations show that 1 m of uniform layer of water corresponds to 31 nm s -2 in gravity and -11 mm in height. Modelled loading is compared with observations of the superconducting gravimeter T020 for years 1994-2002. The combination of HIRLAM and a tide gauge record decreases RMS of gravity residuals by 14% compared to single admittance in air pressure corrections without sea level data. Regression of gravity residuals on the tide gauge record at Helsinki (at 30 km distance) gives a gravity effect of 26 nm s -2 m -1 for Baltic loading. The gravity station is co-located with a permanent GPS station. We have also associated the loading effects of the atmosphere and of the Baltic Sea with temporal height variations. The range of modelled vertical motion due to air pressure was 46 mm and that due to sea level 18 mm. The total range was 38 mm. The effects of the Baltic Sea and of the atmosphere partly cancel each other, since at longer periods the inverse barometer assumption is valid. Regression of the modelled height on local air pressure gives -0.37 mm hPa -1, corresponding approximately to width 6° for pressure system. We have tested the models using one year of daily GPS data. Multilinear regression on local air pressure and sea level in Helsinki gives the coefficient -0.34 mm hPa -1 for pressure, and -11 mm m -1 for sea level. These match model values. Loading by air pressure and

  14. Population genomic evidence for adaptive differentiation in the Baltic Sea herring.

    PubMed

    Guo, Baocheng; Li, Zitong; Merilä, Juha

    2016-06-01

    Detecting and estimating the degree of genetic differentiation among populations of highly mobile marine fish having pelagic larval stages is challenging because their effective population sizes can be large, and thus, little genetic drift and differentiation is expected in neutral genomic sites. However, genomic sites subject to directional selection stemming from variation in local environmental conditions can still show substantial genetic differentiation, yet these signatures can be hard to detect with low-throughput approaches. Using a pooled RAD-seq approach, we investigated genomewide patterns of genetic variability and differentiation within and among 20 populations of Atlantic herring in the Baltic Sea (and adjacent Atlantic sites), where previous low-throughput studies and/or studies based on few populations have found limited evidence for genetic differentiation. Stringent quality control was applied in the filtering of 1 791 254 SNPs, resulting in a final data set of 68 182 polymorphic loci. Clear differentiation was identified between Atlantic and Baltic populations in many genomic sites, while differentiation within the Baltic Sea area was weaker and geographically less structured. However, outlier analyses - whether including all populations or only those within the Baltic Sea - uncovered hundreds of directionally selected loci in which variability was associated with either salinity, temperature or both. Hence, our results support the view that although the degree of genetic differentiation among Baltic Sea herring populations is low, there are many genomic regions showing elevated divergence, apparently as a response to temperature- and salinity-related natural selection. As such, the results add to the increasing evidence of local adaptation in highly mobile marine organisms, and those in the young Baltic Sea in particular. PMID:27093194

  15. Population genomic evidence for adaptive differentiation in the Baltic Sea herring.

    PubMed

    Guo, Baocheng; Li, Zitong; Merilä, Juha

    2016-06-01

    Detecting and estimating the degree of genetic differentiation among populations of highly mobile marine fish having pelagic larval stages is challenging because their effective population sizes can be large, and thus, little genetic drift and differentiation is expected in neutral genomic sites. However, genomic sites subject to directional selection stemming from variation in local environmental conditions can still show substantial genetic differentiation, yet these signatures can be hard to detect with low-throughput approaches. Using a pooled RAD-seq approach, we investigated genomewide patterns of genetic variability and differentiation within and among 20 populations of Atlantic herring in the Baltic Sea (and adjacent Atlantic sites), where previous low-throughput studies and/or studies based on few populations have found limited evidence for genetic differentiation. Stringent quality control was applied in the filtering of 1 791 254 SNPs, resulting in a final data set of 68 182 polymorphic loci. Clear differentiation was identified between Atlantic and Baltic populations in many genomic sites, while differentiation within the Baltic Sea area was weaker and geographically less structured. However, outlier analyses - whether including all populations or only those within the Baltic Sea - uncovered hundreds of directionally selected loci in which variability was associated with either salinity, temperature or both. Hence, our results support the view that although the degree of genetic differentiation among Baltic Sea herring populations is low, there are many genomic regions showing elevated divergence, apparently as a response to temperature- and salinity-related natural selection. As such, the results add to the increasing evidence of local adaptation in highly mobile marine organisms, and those in the young Baltic Sea in particular.

  16. Artificial radionuclides in the surface waters of the Baltic Sea and the North Sea in the fall of 1984

    SciTech Connect

    Kadzhene, G.I.; Kleiza, I.V.; Korotkov, V.P.; Lukinskene, M.V.; Mironov, V.K.; Styro, D.B.

    1987-10-01

    The authors compare data from the literature with data taken in the fall of 1984 on the concentrations of cesium 137, strontium 90, cesium 144, and tritium in the waters of the Baltic and North seas. Sampling was conducted along the coastal regions as well as offshore and the consequent concentration and distribution profiles are mapped. They attempt to assess the weight of meteorological and water current as well as seasonal factors on the determined levels and also point to possible sources of the isotopes, including nuclear power plants situated along Baltic and North Sea shorelines and an atmospheric test of a thermonuclear bomb carried out by China.

  17. BIAS: A Regional Management of Underwater Sound in the Baltic Sea.

    PubMed

    Sigray, Peter; Andersson, Mathias; Pajala, Jukka; Laanearu, Janek; Klauson, Aleksander; Tegowski, Jaroslaw; Boethling, Maria; Fischer, Jens; Tougaard, Jakob; Wahlberg, Magnus; Nikolopoulos, Anna; Folegot, Thomas; Matuschek, Rainer; Verfuss, Ursula

    2016-01-01

    Management of the impact of underwater sound is an emerging concern worldwide. Several countries are in the process of implementing regulatory legislations. In Europe, the Marine Strategy Framework Directive was launched in 2008. This framework addresses noise impacts and the recommendation is to deal with it on a regional level. The Baltic Sea is a semienclosed area with nine states bordering the sea. The number of ships is one of the highest in Europe. Furthermore, the number of ships is estimated to double by 2030. Undoubtedly, due to the unbound character of noise, an efficient management of sound in the Baltic Sea must be done on a regional scale. In line with the European Union directive, the Baltic Sea Information on the Acoustic Soundscape (BIAS) project was established to implement Descriptor 11 of the Marine Strategy Framework Directive in the Baltic Sea region. BIAS will develop tools, standards, and methodologies that will allow for cross-border handling of data and results, measure sound in 40 locations for 1 year, establish a seasonal soundscape map by combining measured sound with advanced three-dimensional modeling, and, finally, establish standards for measuring continuous sound. Results from the first phase of BIAS are presented here, with an emphasis on standards and soundscape mapping as well as the challenges related to regional handling.

  18. Temporal variatiions of Sea ice cover in the Baltic Sea derived from operational sea ice products used in NWP.

    NASA Astrophysics Data System (ADS)

    Lange, Martin; Paul, Gerhard; Potthast, Roland

    2014-05-01

    Sea ice cover is a crucial parameter for surface fluxes of heat and moisture over water areas. The isolating effect and the much higher albedo strongly reduces the turbulent exchange of heat and moisture from the surface to the atmosphere and allows for cold and dry air mass flow with strong impact on the stability of the whole boundary layer and consequently cloud formation as well as precipitation in the downstream regions. Numerical weather centers as, ECMWF, MetoFrance or DWD use external products to initialize SST and sea ice cover in their NWP models. To the knowledge of the author there are mainly two global sea ice products well established with operational availability, one from NOAA NCEP that combines measurements with satellite data, and the other from OSI-SAF derived from SSMI/S sensors. The latter one is used in the Ostia product. DWD additionally uses a regional product for the Baltic Sea provided by the national center for shipping and hydrografie which combines observations from ships (and icebreakers) for the German part of the Baltic Sea and model analysis from the hydrodynamic HIROMB model of the Swedish meteorological service for the rest of the domain. The temporal evolution of the three different products are compared for a cold period in Februar 2012. Goods and bads will be presented and suggestions for a harmonization of strong day to day jumps over large areas are suggested.

  19. Glyphosate and AMPA in the estuaries of the Baltic Sea method optimization and field study.

    PubMed

    Skeff, Wael; Neumann, Christine; Schulz-Bull, Detlef E

    2015-11-15

    Water samples from ten German Baltic estuaries were collected in 2012 in order to study the presence of the herbicide glyphosate, its primary metabolite AMPA and their potential transport to the marine environment. For the analyses an LC-MS/MS based analytical method after derivatization with FMOC-Cl was optimized and validated for marine water samples. All investigated estuarine stations were contaminated with AMPA and nine of them also with glyphosate. Concentration ranges observed were 28 to 1690ng/L and 45 to 4156ng/L for glyphosate and AMPA, respectively with strong spatial and temporal fluctuations. Both contaminants were found at inbound sampling sites in the stream Muehlenfliess and concentrations decreased along the salinity gradient to the estuaries of the Baltic Sea. The data obtained in this study clearly depict the transport of glyphosate and AMPA to the Baltic Sea. Hence, detailed fate and risk assessment for both contaminants in marine environments are required.

  20. Visual pigments of Baltic Sea fishes of marine and limnic origin.

    PubMed

    Jokela-Määttä, Mirka; Smura, Teemu; Aaltonen, Anna; Ala-Laurila, Petri; Donner, Kristian

    2007-01-01

    Absorbance spectra of rods and some cones were measured by microspectrophotometry in 22 fish species from the brackish-water of the Baltic Sea, and when applicable, in the same species from the Atlantic Ocean (3 spp.), the Mediterranean Sea (1 sp.), or Finnish fresh-water lakes (9 spp.). The main purpose was to study whether there were differences suggesting spectral adaptation of rod vision to different photic environments during the short history (<10(4) years) of postglacial isolation of the Baltic Sea and the Finnish lakes. Rod absorbance spectra of the Baltic subspecies/populations of herring (Clupea harengus membras), flounder (Platichthys flesus), and sand goby (Pomatoschistus minutus) were all long-wavelength-shifted (9.8, 1.9, and 5.3 nm, respectively, at the wavelength of maximum absorbance, lambda(max)) compared with their truly marine counterparts, consistent with adaptation for improved quantum catch, and improved signal-to-noise ratio of vision in the Baltic light environment. Judged by the shape of the spectra, the chromophore was pure A1 in all these cases; hence the differences indicate evolutionary tuning of the opsin. In no species of fresh-water origin did we find significant opsin-based spectral shifts specific to the Baltic populations, only spectral differences due to varying A1/A2 chromophore ratio in some. For most species, rod lambda(max) fell within a wavelength range consistent with high signal-to-noise ratio of vision in the spectral conditions prevailing at depths where light becomes scarce in the respective waters. Exceptions were sandeels in the Baltic Sea, which are active only in bright light, and all species in a "brown" lake, where rod lambda(max) lay far below the theoretically optimal range. PMID:17822578

  1. Meteorological conditions influencing the formation of level ice within the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Mazur, A. K.; Krezel, A.

    2012-12-01

    The Baltic Sea is covered by ice every winter and on average, the ice-covered area is 45% of the total area of the Baltic Sea. The beginning of ice season usually starts in the end of November, ice extent is the largest between mid-February and mid-March and sea ice disappears completely in May. The ice covered areas during a typical winter are the Gulf of Bothnia, the Gulf of Finland and the Gulf of Riga. The studies of sea ice in the Baltic Sea are related to two aspects: climate and marine transport. Depending on the local weather conditions during the winter different types of sea ice can be formed. From the point of winter shipping it is important to locate level and deformed ice areas (rafted ice, ridged ice, and hummocked ice). Because of cloud and daylight independency as well as good spatial resolution, SAR data seems to be the most suitable source of data for sea ice observation in the comparatively small area of the Baltic Sea. We used ASAR Wide Swath Mode data with spatial resolution 150 m. We analyzed data from the three winter seasons which were examples of severe, typical and mild winters. To remove the speckle effect the data were resampled to 250 m pixel size and filtred using Frost filter 5x5. To detect edges we used Sobel filter. The data were also converted into grayscale. Sea ice classification was based on Object-Based Image Analysis (OBIA). Object-based methods are not a common tool in sea ice studies but they seem to accurately separate level ice within the ice pack. The data were segmented and classified using eCognition Developer software. Level ice were classified based on texture features defined by Haralick (Grey Level Co-Occurrence Matrix homogeneity, GLCM contrast, GLCM entropy and GLCM correlation). The long-term changes of the Baltic Sea ice conditions have been already studied. They include date of freezing, date of break-up, sea ice extent and some of work also ice thickness. There is a little knowledge about the relationship of

  2. Assessment of PCDD/F source contributions in Baltic Sea sediment core records.

    PubMed

    Assefa, Anteneh T; Tysklind, Mats; Sobek, Anna; Sundqvist, Kristina L; Geladi, Paul; Wiberg, Karin

    2014-08-19

    Spatial and temporal trends of sources of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the Baltic Sea were evaluated by positive matrix factorization (PMF) and principal component analysis (PCA). Sediment cores were sampled at eight coastal, one coastal reference, and six offshore sites covering the northern to the southern Baltic Sea. The cores, which covered the period 1919-2010, were sliced into 2-3 cm disks among which 8-11 disks per core (in total 141 disks) were analyzed for all tetra- through octa-CDD/Fs. Identification and apportionment of PCDD/F sources was carried out using PMF. Five stable model PCDD/F congener patterns were identified, which could be associated with six historically important source types: (i) atmospheric background deposition (ABD), (ii) use and production of penta-chlorophenol (PCP), (iii) use and production of tetra-chlorophenol (TeCP), (iv) high temperature processes (Thermal), (v) hexa-CDD-related sources (HxCDD), and (vi) chlorine-related sources (Chl), all of which were still represented in the surface layers. Overall, the last four decades of the period 1920-2010 have had a substantial influence on the Baltic Sea PCDD/F pollution, with 88 ± 7% of the total amount accumulated during this time. The 1990s was the peak decade for all source types except TeCP, which peaked in the 1980s in the northern Baltic Sea and has still not peaked in the southern part. The combined impact of atmospheric-related emissions (ABD and Thermal) was dominant in the open sea system throughout the study period (1919-2010) and showed a decreasing south to north trend (always >80% in the south and >50% in the north). Accordingly, to further reduce levels of PCDD/Fs in the open Baltic Sea ecosystem, future actions should focus on reducing atmospheric emissions.

  3. Assessing Secchi and photic zone depth in the Baltic Sea from satellite data.

    PubMed

    Kratzer, Susanne; Håkansson, Bertil; Sahlin, Charlotte

    2003-12-01

    Long-term trends in the Secchi depth of the Baltic Sea have been interpreted in terms of eutrophication. The spectral attenuation coefficient Kd (490) can be estimated from remote sensing data. Given the empirical and theoretical relationships between diffuse attenuation and Secchi depth, it is therefore possible to estimate the trophic state from remote sensing data. This paper considers relationships among remotely sensed and in-water measured K (490), and Secchi depth data obtained during dedicated sea-truthing campaigns in the eastern Baltic Proper in 1999 (4) and in the western Baltic Proper/Himmerfjärden area during 2001 and 2002. In-water measurements are used to establish the relationship between the PAR and the spectral attenuation coefficient in the Baltic Sea via regression analysis. The analysis showed that in the area of investigation Kd(490) is about 1.48 times higher than Kd (PAR). This relationship is then used to define the link between the photic zone depth and the remote sensing optical depth, Kd (490)-1. The results show that the depth of the euphotic zone is about 6.8 times Kd (490)-1. The regression analysis between Kd (PAR) and Secchi depth confirmed previous work that Kd (PAR) is about 1.7 of the inverse Secchi depth. Furthermore, an in-water algorithm between Secchi depth and Kd (490) is used to simulate a Secchi depth map of the Baltic Sea from SeaWiFS Kd(490) data. This map is verified against sea-truthing data. Kd (490) data derived from satellite is compared to in situ Kd (490), and the sources of error are discussed. PMID:15049356

  4. Assessing Secchi and photic zone depth in the Baltic Sea from satellite data.

    PubMed

    Kratzer, Susanne; Håkansson, Bertil; Sahlin, Charlotte

    2003-12-01

    Long-term trends in the Secchi depth of the Baltic Sea have been interpreted in terms of eutrophication. The spectral attenuation coefficient Kd (490) can be estimated from remote sensing data. Given the empirical and theoretical relationships between diffuse attenuation and Secchi depth, it is therefore possible to estimate the trophic state from remote sensing data. This paper considers relationships among remotely sensed and in-water measured K (490), and Secchi depth data obtained during dedicated sea-truthing campaigns in the eastern Baltic Proper in 1999 (4) and in the western Baltic Proper/Himmerfjärden area during 2001 and 2002. In-water measurements are used to establish the relationship between the PAR and the spectral attenuation coefficient in the Baltic Sea via regression analysis. The analysis showed that in the area of investigation Kd(490) is about 1.48 times higher than Kd (PAR). This relationship is then used to define the link between the photic zone depth and the remote sensing optical depth, Kd (490)-1. The results show that the depth of the euphotic zone is about 6.8 times Kd (490)-1. The regression analysis between Kd (PAR) and Secchi depth confirmed previous work that Kd (PAR) is about 1.7 of the inverse Secchi depth. Furthermore, an in-water algorithm between Secchi depth and Kd (490) is used to simulate a Secchi depth map of the Baltic Sea from SeaWiFS Kd(490) data. This map is verified against sea-truthing data. Kd (490) data derived from satellite is compared to in situ Kd (490), and the sources of error are discussed.

  5. Anisakid larvae in the liver of cod (Gadus morhua) L. from the southern Baltic Sea.

    PubMed

    Nadolna, K; Podolska, M

    2014-06-01

    In the present investigation a sample of 490 cod (Gadus morhua) was examined from three regions in the southern Baltic Sea (the Polish Exclusive Economic Zone, EEZ). Three species of anisakid nematodes with zoonotic potential, namely species of Contracaecum, Anisakis and Pseudoterranova, were found in the liver of cod, with Contracaecum being the most dominant species. The prevalence of infection was highest in the Western Baltic (22.5%) compared to the Central Baltic (10.4%) and the Gulf of Gdansk (3.4%). Generalized linear models (GLMs) were applied to analyse the prevalence of infection with Anisakis sp. and Contracaecum sp. relative to biological and spatial parameters. The effect of the sampling region, age and body length of the fish were significant in both GLMs. The effect of region was higher in the Western Baltic than in other regions. The prevalence of infection was correlated with the length of the fish and was higher in adult compared with sub-adult fish. These results suggest that the prevalence of infection with anisakid nematodes (especially Contracaecum sp.) in cod sampled in Polish waters of the Baltic Sea has significantly increased compared with previous studies undertaken over the past few decades. PMID:23452650

  6. Diversity of Pico- to Mesoplankton along the 2000 km Salinity Gradient of the Baltic Sea.

    PubMed

    Hu, Yue O O; Karlson, Bengt; Charvet, Sophie; Andersson, Anders F

    2016-01-01

    Microbial plankton form the productive base of both marine and freshwater ecosystems and are key drivers of global biogeochemical cycles of carbon and nutrients. Plankton diversity is immense with representations from all major phyla within the three domains of life. So far, plankton monitoring has mainly been based on microscopic identification, which has limited sensitivity and reproducibility, not least because of the numerical majority of plankton being unidentifiable under the light microscope. High-throughput sequencing of taxonomic marker genes offers a means to identify taxa inaccessible by traditional methods; thus, recent studies have unveiled an extensive previously unknown diversity of plankton. Here, we conducted ultra-deep Illumina sequencing (average 10(5) sequences/sample) of rRNA gene amplicons of surface water eukaryotic and bacterial plankton communities sampled in summer along a 2000 km transect following the salinity gradient of the Baltic Sea. Community composition was strongly correlated with salinity for both bacterial and eukaryotic plankton assemblages, highlighting the importance of salinity for structuring the biodiversity within this ecosystem. In contrast, no clear trends in alpha-diversity for bacterial or eukaryotic communities could be detected along the transect. The distribution of major planktonic taxa followed expected patterns as observed in monitoring programs, but groups novel to the Baltic Sea were also identified, such as relatives to the coccolithophore Emiliana huxleyi detected in the northern Baltic Sea. This study provides the first ultra-deep sequencing-based survey on eukaryotic and bacterial plankton biogeography in the Baltic Sea. PMID:27242706

  7. PHOTOCHEMICAL MINERALIZATION OF DISSOLVED ORGANIC NITROGEN TO AMMONIUM IN THE BALTIC SEA

    EPA Science Inventory

    Solar radiation-induced photochemistry can be considered as a new source of nutrients when photochemical reactions release bioavailable nitrogen from biologically non-reactive dissolved organic nitrogen (DON). Pretreatments of Baltic Sea waters in the dark indicated that >72% of ...

  8. Marine landscapes and population genetic structure of herring (Clupea harengus L.) in the Baltic Sea.

    PubMed

    Jørgensen, Hanne B H; Hansen, Michael M; Bekkevold, Dorte; Ruzzante, Daniel E; Loeschcke, Volker

    2005-09-01

    Numerically small but statistically significant genetic differentiation has been found in many marine fish species despite very large census population sizes and absence of obvious barriers to migrating individuals. Analyses of morphological traits have previously identified local spawning groups of herring (Clupea harengus L.) in the environmentally heterogeneous Baltic Sea, whereas allozyme markers have not revealed differentiation. We analysed variation at nine microsatellite loci in 24 samples of spring-spawning herring collected at 11 spawning locations throughout the Baltic Sea. Significant temporal differentiation was observed at two locations, which we ascribe to sympatrically spawning but genetically divergent 'spawning waves'. Significant differentiation was also present on a geographical scale, though pairwise F(ST) values were generally low, not exceeding 0.027. Partial Mantel tests showed no isolation by geographical distance, but significant associations were observed between genetic differentiation and environmental parameters (salinity and surface temperature) (0.001 < P < or = 0.099), though these outcomes were driven mainly by populations in the southwestern Baltic Sea, which also exhibits the steepest environmental gradients. Application of a novel method for detecting barriers to gene flow by combining geographical coordinates and genetic differentiation allowed us to identify two zones of lowered gene flow. These zones were concordant with the separation of the Baltic Sea into major basins, with environmental gradients and with differences in migration behaviour. We suggest that similar use of landscape genetics approaches may increase the understanding of the biological significance of genetic differentiation in other marine fishes.

  9. Diversity of Pico- to Mesoplankton along the 2000 km Salinity Gradient of the Baltic Sea

    PubMed Central

    Hu, Yue O. O.; Karlson, Bengt; Charvet, Sophie; Andersson, Anders F.

    2016-01-01

    Microbial plankton form the productive base of both marine and freshwater ecosystems and are key drivers of global biogeochemical cycles of carbon and nutrients. Plankton diversity is immense with representations from all major phyla within the three domains of life. So far, plankton monitoring has mainly been based on microscopic identification, which has limited sensitivity and reproducibility, not least because of the numerical majority of plankton being unidentifiable under the light microscope. High-throughput sequencing of taxonomic marker genes offers a means to identify taxa inaccessible by traditional methods; thus, recent studies have unveiled an extensive previously unknown diversity of plankton. Here, we conducted ultra-deep Illumina sequencing (average 105 sequences/sample) of rRNA gene amplicons of surface water eukaryotic and bacterial plankton communities sampled in summer along a 2000 km transect following the salinity gradient of the Baltic Sea. Community composition was strongly correlated with salinity for both bacterial and eukaryotic plankton assemblages, highlighting the importance of salinity for structuring the biodiversity within this ecosystem. In contrast, no clear trends in alpha-diversity for bacterial or eukaryotic communities could be detected along the transect. The distribution of major planktonic taxa followed expected patterns as observed in monitoring programs, but groups novel to the Baltic Sea were also identified, such as relatives to the coccolithophore Emiliana huxleyi detected in the northern Baltic Sea. This study provides the first ultra-deep sequencing-based survey on eukaryotic and bacterial plankton biogeography in the Baltic Sea. PMID:27242706

  10. Diversity of Pico- to Mesoplankton along the 2000 km Salinity Gradient of the Baltic Sea.

    PubMed

    Hu, Yue O O; Karlson, Bengt; Charvet, Sophie; Andersson, Anders F

    2016-01-01

    Microbial plankton form the productive base of both marine and freshwater ecosystems and are key drivers of global biogeochemical cycles of carbon and nutrients. Plankton diversity is immense with representations from all major phyla within the three domains of life. So far, plankton monitoring has mainly been based on microscopic identification, which has limited sensitivity and reproducibility, not least because of the numerical majority of plankton being unidentifiable under the light microscope. High-throughput sequencing of taxonomic marker genes offers a means to identify taxa inaccessible by traditional methods; thus, recent studies have unveiled an extensive previously unknown diversity of plankton. Here, we conducted ultra-deep Illumina sequencing (average 10(5) sequences/sample) of rRNA gene amplicons of surface water eukaryotic and bacterial plankton communities sampled in summer along a 2000 km transect following the salinity gradient of the Baltic Sea. Community composition was strongly correlated with salinity for both bacterial and eukaryotic plankton assemblages, highlighting the importance of salinity for structuring the biodiversity within this ecosystem. In contrast, no clear trends in alpha-diversity for bacterial or eukaryotic communities could be detected along the transect. The distribution of major planktonic taxa followed expected patterns as observed in monitoring programs, but groups novel to the Baltic Sea were also identified, such as relatives to the coccolithophore Emiliana huxleyi detected in the northern Baltic Sea. This study provides the first ultra-deep sequencing-based survey on eukaryotic and bacterial plankton biogeography in the Baltic Sea.

  11. Valuing the commons: An international study on the recreational benefits of the Baltic Sea.

    PubMed

    Czajkowski, Mikołaj; Ahtiainen, Heini; Artell, Janne; Budziński, Wiktor; Hasler, Berit; Hasselström, Linus; Meyerhoff, Jürgen; Nõmmann, Tea; Semeniene, Daiva; Söderqvist, Tore; Tuhkanen, Heidi; Lankia, Tuija; Vanags, Alf; Zandersen, Marianne; Żylicz, Tomasz; Hanley, Nick

    2015-06-01

    The Baltic Sea provides benefits to all of the nine nations along its coastline, with some 85 million people living within the catchment area. Achieving improvements in water quality requires international cooperation. The likelihood of effective cooperation is known to depend on the distribution across countries of the benefits and costs of actions needed to improve water quality. In this paper, we estimate the benefits associated with recreational use of the Baltic Sea in current environmental conditions using a travel cost approach, based on data from a large, standardized survey of households in each of the 9 Baltic Sea states. Both the probability of engaging in recreation (participation) and the number of visits people make are modeled. A large variation in the number of trips and the extent of participation is found, along with large differences in current annual economic benefits from Baltic Sea recreation. The total annual recreation benefits are close to 15 billion EUR. Under a water quality improvement scenario, the proportional increases in benefits range from 7 to 18% of the current annual benefits across countries. Depending on how the costs of actions are distributed, this could imply difficulties in achieving more international cooperation to achieve such improvements.

  12. Valuing the commons: An international study on the recreational benefits of the Baltic Sea.

    PubMed

    Czajkowski, Mikołaj; Ahtiainen, Heini; Artell, Janne; Budziński, Wiktor; Hasler, Berit; Hasselström, Linus; Meyerhoff, Jürgen; Nõmmann, Tea; Semeniene, Daiva; Söderqvist, Tore; Tuhkanen, Heidi; Lankia, Tuija; Vanags, Alf; Zandersen, Marianne; Żylicz, Tomasz; Hanley, Nick

    2015-06-01

    The Baltic Sea provides benefits to all of the nine nations along its coastline, with some 85 million people living within the catchment area. Achieving improvements in water quality requires international cooperation. The likelihood of effective cooperation is known to depend on the distribution across countries of the benefits and costs of actions needed to improve water quality. In this paper, we estimate the benefits associated with recreational use of the Baltic Sea in current environmental conditions using a travel cost approach, based on data from a large, standardized survey of households in each of the 9 Baltic Sea states. Both the probability of engaging in recreation (participation) and the number of visits people make are modeled. A large variation in the number of trips and the extent of participation is found, along with large differences in current annual economic benefits from Baltic Sea recreation. The total annual recreation benefits are close to 15 billion EUR. Under a water quality improvement scenario, the proportional increases in benefits range from 7 to 18% of the current annual benefits across countries. Depending on how the costs of actions are distributed, this could imply difficulties in achieving more international cooperation to achieve such improvements. PMID:25846001

  13. Late- and Postglacial Sea-Level Change and Paleoenvironments in the Oder Estuary, Southern Baltic Sea

    NASA Astrophysics Data System (ADS)

    Müller, Anne

    2001-01-01

    Knowledge of sea-level change in the southern Baltic Sea region is important for understanding the variations in late Pleistocene and Holocene sea-level change across northern Europe. These variations are a consequence of the response of the Earth's crust to the deglaciation of Fennoscandia and of the water added to the oceans from the melting of all Pleistocene ice sheets. The sedimentological and geochemical composition of five sediment cores from the lagoonal Oder Estuary offers new observational evidence for sea-level change and coastal development in the southern Baltic Sea region. The combined use of several geochemical proxies (organic carbon, nitrogen, calcium carbonate and biogenic opal contents, Corg/S and Corg/N ratios, δ13C values of organic matter, and δ15N values) is a new approach for the study area. The chemical evidence of this multiproxy approach allows clear identification of several stages in the development of the lagoonal environment: postglacial lake stages with sandy sedimentation during the Older Dryas and the Allerød stades, lacustrine phases with high autochthonous productivity during the Atlantic stade, terrestrial stages with peat formation at the beginning of the Subboreal stade, sedimentation as a result of marine transgression, and brackish sedimentation after the formation of sand spits and barrier islands during the Subatlantic stade. The stages are the result of regional sea-level change owing to complex shoreline development. They support the tentative sea-level curve proposed nearly 20 years ago for the region. In addition, changes in Oder River input in response to climate conditions is monitored. Whereas high terrigenous input of organic matter from the Oder River occurred during periods of humid climate during the Allerød, Atlantic, and Subatlantic stades, Oder River discharge decreased with drier and cooler climate conditions during the Subboreal stade. Furthermore, the geochemical evidence points to local anomalies such

  14. The role of open ocean boundary forcing on potential warming in the North and Baltic Seas

    NASA Astrophysics Data System (ADS)

    Tian, Tian; Su, Jian; Boberg, Fredrik; Yang, Shuting

    2013-04-01

    To study uncertainty in the regional model of using temperature boundary conditions from the ocean models covering larger areas at reduced resolution, like GCMs, the EC-Earth CMIP5 Experiments are used to provide lateral boundary forcing for the regional atmospheric model (HIRHAM) and the regional ocean model (HBM) in the North and Baltic Seas. HIRHAM has been extensively used over the European region to downscale variability and climate change signals from the global model, for instance during the PRUDENCE project. The downscaling simulation started from January 1, 1960 and was implemented for the historical period of 1960 to 2009 and for the continuing future period of 2010 to 2100 for the two scenarios RCP8.5 and RCP4.5. The effects of using different prescribed temperature boundary conditions in the northern North Sea and the English Channel borders on potential warming in the North and Baltic Seas are investigated. The lateral transport of heat and the details of density structure of the boundary conditions have relatively large impact in the deeper oceanic regions in the northern North Sea, but little in the southern North Sea. The effect in the Baltic Sea and the transition area between the two regional seas is negligible.

  15. Ice formation and growth shape bacterial community structure in Baltic Sea drift ice.

    PubMed

    Eronen-Rasimus, Eeva; Lyra, Christina; Rintala, Janne-Markus; Jürgens, Klaus; Ikonen, Vilma; Kaartokallio, Hermanni

    2015-02-01

    Drift ice, open water and under-ice water bacterial communities covering several developmental stages from open water to thick ice were studied in the northern Baltic Sea. The bacterial communities were assessed with 16S rRNA gene terminal-restriction fragment length polymorphism and cloning, together with bacterial abundance and production measurements. In the early stages, open water and pancake ice were dominated by Alphaproteobacteria and Actinobacteria, which are common bacterial groups in Baltic Sea wintertime surface waters. The pancake ice bacterial communities were similar to the open-water communities, suggesting that the parent water determines the sea-ice bacterial community in the early stages of sea-ice formation. In consolidated young and thick ice, the bacterial communities were significantly different from water bacterial communities as well as from each other, indicating community development in Baltic Sea drift ice along with ice-type changes. The thick ice was dominated by typical sea-ice genera from classes Flavobacteria and Gammaproteobacteria, similar to those in polar sea-ice bacterial communities. Since the thick ice bacterial community was remarkably different from that of the parent seawater, results indicate that thick ice bacterial communities were recruited from the rarer members of the seawater bacterial community.

  16. Trend Analysis of Nitrogen Deposition to Baltic Sea and its sub basins

    NASA Astrophysics Data System (ADS)

    Semeena, V. S.; Jerzy, Bartnicki

    2009-04-01

    Since the beginning of last century, Baltic Sea has changed from a clear-water sea into a eutrophic marine environment. Eutrophication is the major problem in the Baltic Sea. Excessive nitrogen and phosphorus loads coming from land-based sources within and outside the catchment area of the bordering countries of the Baltic Sea are the main cause of the eutrophication in the sea. Even though a major part of nitrogen(75%) and phosphorus load(95%) enter the sea via rivers or as water-born discharges, 25% of the nitrogen load comes as atmospheric deposition. Numerical models are the best tools to measure atmospheric deposition into sea waters. We have used the latest version of the Unified EMEP model - which has been developed at the EMEP/MSC-W (Meteorological Synthesizing Centre - West of EMEP) for simulating atmospheric transport and deposition of acidifying and eutrophying compounds as well as photo-oxidants in Europe- to study the trends in atmospheric deposition of nitrogen into Baltic Sea for the period 1995-2006. The model domain covers Europe and the Atlantic Ocean. The model grid (of the size 170×133) has a horizontal resolution of 50 km at 60o N, which is consistent with the resolution of emission data reported to CLRTAP. Approximately 10 of these layers are placed below 2 km to obtain high resolution of the boundary layer which is of special importance to the long range transport of air pollution. EMEP model has been thouroughly validated (Fagerli et.al.[1], Simpson et.al.[2], Simpson et.al.[3] ) The contribution of deposition of nitrogen into Baltic Sea from each of the bordering countries of the Baltic Sea and the deposition trends for the period 1995-2006 has been analysed and the results will be presented. References: [1]. Fagerli H., Simpson D. and Aas W.: Model performance for sulphur and nitrogen compounds for the period 1980 to 2000. [In:] L. Tarraśon, (editor), Transboundary Acidification, Eutrophication and Ground Level Ozone in Europe. EMEP

  17. Dynamical downscaling of warming scenarios with NEMO-Nordic setup for the North Sea and Baltic Sea

    NASA Astrophysics Data System (ADS)

    Gröger, Matthias; Almroth Rosell, Elin; Anderson, Helén; Axell, Lars; Dieterich, Christain; Edman, Moa; Eilola, Kari; Höglund, Anders; Hordoir, Robinson; Hieronymus, Jenny; Karlsson, Bengt; Liu, Ye; Meier, Markus; Pemberton, Per; Saraiva, Sofia

    2016-04-01

    The North Sea and Baltic Sea constitute one of the most complex and challenging areas in the world. The oceanographic setting ranges from quasi open ocean conditions in the northern North Sea to more brackish conditions in the Baltic Sea which is also affected by sea ice in winter. The two seas are connected by narrow straits which sporadically allow the important inflow of salt and oxygen rich bottom waters into the Baltic Sea. For this, the high resolution regional model NEMO-Nordic has recently been developed. Here, the model is applied on hindcast simulations and used to downscale several climate warming scenarios. The model can be interactively coupled to the regional atmosphere model RCA4 by exchanging air sea fluxes of mass and energy (Wang et al., 2015). Comparison with well established models and newly compiled observational data sets (Bersch et al., 2013) indicates NEMO-Nordic performs well on climate relevant time scales. Emphasis is laid on thermal dynamics. Hindcast simulations demonstrate that simulated winter temperatures in the Baltic Sea can benefit from interactive air sea coupling by allowing interactive feedback loops to take place between the ocean and the atmosphere (Gröger et al. 2015). Likewise, a more realistic dynamical behaviour makes the interactive coupled model suitable for dynamic downscaling of climate warming scenarios. Depending on the driving global climate model and IPCC representative concentration pathway scenario NEMO-Nordic shows an average warming of the North Sea between 2 and 4 K at the end of the 21st century. However the warming pattern is spatially inhomogeneous showing strong east west gradients. Involved processes such as circulation changes and changes in radiative forcing will be discussed. Bersch, M., Gouretski, V., Sadikni, R., Hinrichs, I., 2013. Hydrographic climatology of the North Sea and surrounding regions. Centre for Earth System Research and Sustainability, University of Hamburg, www

  18. Local adaptation and oceanographic connectivity patterns explain genetic differentiation of a marine diatom across the North Sea-Baltic Sea salinity gradient.

    PubMed

    Sjöqvist, C; Godhe, A; Jonsson, P R; Sundqvist, L; Kremp, A

    2015-06-01

    Drivers of population genetic structure are still poorly understood in marine micro-organisms. We exploited the North Sea-Baltic Sea transition for investigating the seascape genetics of a marine diatom, Skeletonema marinoi. Eight polymorphic microsatellite loci were analysed in 354 individuals from ten locations to analyse population structure of the species along a 1500-km-long salinity gradient ranging from 3 to 30 psu. To test for salinity adaptation, salinity reaction norms were determined for sets of strains originating from three different salinity regimes of the gradient. Modelled oceanographic connectivity was compared to directional relative migration by correlation analyses to examine oceanographic drivers. Population genetic analyses showed distinct genetic divergence of a low-salinity Baltic Sea population and a high-salinity North Sea population, coinciding with the most evident physical dispersal barrier in the area, the Danish Straits. Baltic Sea populations displayed reduced genetic diversity compared to North Sea populations. Growth optima of low salinity isolates were significantly lower than those of strains from higher native salinities, indicating local salinity adaptation. Although the North Sea-Baltic Sea transition was identified as a barrier to gene flow, migration between Baltic Sea and North Sea populations occurred. However, the presence of differentiated neutral markers on each side of the transition zone suggests that migrants are maladapted. It is concluded that local salinity adaptation, supported by oceanographic connectivity patterns creating an asymmetric migration pattern between the Baltic Sea and the North Sea, determines genetic differentiation patterns in the transition zone.

  19. A comprehensive inventory of ship traffic exhaust emissions in the European sea areas in 2011

    NASA Astrophysics Data System (ADS)

    Jalkanen, J.-P.; Johansson, L.; Kukkonen, J.

    2016-01-01

    Emissions originating from ship traffic in European sea areas were modelled using the Ship Traffic Emission Assessment Model (STEAM), which uses Automatic Identification System data to describe ship traffic activity. We have estimated the emissions from ship traffic in the whole of Europe in 2011. We report the emission totals, the seasonal variation, the geographical distribution of emissions, and their disaggregation between various ship types and flag states. The total ship emissions of CO2, NOx, SOx, CO, and PM2.5 in Europe for year 2011 were estimated to be 121, 3.0, 1.2, 0.2, and 0.2 million tons, respectively. The emissions of CO2 from the Baltic Sea were evaluated to be more than a half (55 %) of the emissions of the North Sea shipping; the combined contribution of these two sea regions was almost as high (88 %) as the total emissions from ships in the Mediterranean. As expected, the shipping emissions of SOx were significantly lower in the SOx Emission Control Areas, compared with the corresponding values in the Mediterranean. Shipping in the Mediterranean Sea is responsible for 40 and 49 % of the European ship emitted CO2 and SOx emissions, respectively. In particular, this study reported significantly smaller emissions of NOx, SOx, and CO for shipping in the Mediterranean than the EMEP inventory; however, the reported PM2.5 emissions were in a fairly good agreement with the corresponding values reported by EMEP. The vessels registered to all EU member states are responsible for 55 % of the total CO2 emitted by ships in the study area. The vessels under the flags of convenience were responsible for 25 % of the total CO2 emissions.

  20. A comprehensive inventory of ship traffic exhaust emissions in the European sea areas in 2011

    NASA Astrophysics Data System (ADS)

    Jalkanen, J.-P.; Johansson, L.; Kukkonen, J.

    2015-03-01

    Emissions originated from ship traffic in European sea areas were modelled using the Ship Traffic Emission Assessment Model (STEAM), which uses Automatic Identification System data to describe ship traffic activity. We have estimated the emissions from ship traffic in the whole of Europe in 2011. We report the emission totals, the seasonal variation, the geographical distribution of emissions, and their disaggregation between various ship types and flag states. The total ship emissions of CO2, NOx, SOx, CO and PM2.5 in Europe for year 2011 were estimated to be 131, 2.9, 1.2, 0.2 and 0.3 million tons, respectively. The emissions of CO2 from Baltic Sea were evaluated to be more than a half (58%) of the emissions of the North Sea shipping; the combined contribution of these two sea regions was almost as high (96%) as the total emissions from ships in the Mediterranean. As expected, the shipping emissions of SOx were significantly lower in the SOx Emission Control Areas, compared with the corresponding values in the Mediterranean. Shipping in the Mediterranean Sea is responsible for 39 and 49% of the European ship emitted CO2 and SOx emissions, respectively. In particular, this study reported significantly smaller emissions of NOx, SOx and CO for shipping in the Mediterranean than the EMEP inventory; however, the reported PM2.5 emissions were in a fairly good agreement with the corresponding values reported by EMEP. The vessels registered to all EU member states are responsible for 55% of the total CO2 emitted by ships in the study area. The vessels under the flags of convenience were responsible for 25% of the total CO2 emissions.

  1. Mussel farming as a nutrient reduction measure in the Baltic Sea: consideration of nutrient biogeochemical cycles.

    PubMed

    Stadmark, J; Conley, D J

    2011-07-01

    Nutrient loads from the land to the sea must be reduced to combat coastal eutrophication. It has been suggested that further mitigation efforts are needed in the brackish Baltic Sea to decrease nutrients, especially in eutrophic coastal areas. Mussel farming is a potential measure to remove nutrients directly from the sea. Mussels consume phytoplankton containing nitrogen (N) and phosphorus (P); when the mussels are harvested these nutrients are removed from the aquatic system. However, sedimentation of organic material in faeces and pseudo-faeces below a mussel farm consumes oxygen and can lead to hypoxic or even anoxic sediments causing an increased sediment release of ammonium and phosphate. Moreover, N losses from denitrification can be reduced due to low oxygen and reduced numbers of bioturbating organisms. To reveal if mussel farming is a cost-effective mitigation measure in the Baltic Sea the potential for enhanced sediment nutrient release must be assessed.

  2. Physiological plasticity is key to the presence of the isopod Idotea baltica (Pallas) in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Wood, Hannah L.; Nylund, Göran; Eriksson, Susanne P.

    2014-01-01

    The low salinity of the Baltic Sea presents a physiological challenge to marine species. The marine isopod Idotea baltica is notably dominant among the shallow sublittoral of the Baltic Sea in association with Fucus vesiculosus, with permanent populations documented in salinities as low as 3 psu. To investigate the role of physiological plasticity in the successful colonisation of the Baltic by I. baltica three populations from the Swedish coast were here studied, one from the Kattegat (Malmö) and two from the Baltic Sea (Kalmar and Öregrund). These three sites cover the geographic range of this species within the Baltic Sea on the Swedish coast, and also the salinity range of this species within the Baltic Sea (10-5 psu). Individuals from these populations were exposed in the laboratory to a fully crossed experiment with the factors salinity and food source, to test for differences in the physiology of these populations under different conditions that may indicate local adaptation, or no differences that indicate physiological plasticity to differing salinity and food source. Metabolic rate, growth and thermal tolerance responses did not differ between the three populations across salinity treatments after a 12 week exposure. The results of this study indicate that the physiology of adult I. baltica is highly plastic with regard to salinity; this plasticity is likely to have facilitated their colonisation of the Baltic Sea.

  3. BALTEX—an interdisciplinary research network for the Baltic Sea region

    NASA Astrophysics Data System (ADS)

    Reckermann, Marcus; Langner, Joakim; Omstedt, Anders; von Storch, Hans; Keevallik, Sirje; Schneider, Bernd; Arheimer, Berit; Markus Meier, H. E.; Hünicke, Birgit

    2011-10-01

    BALTEX is an environmental research network dealing with the Earth system of the entire Baltic Sea drainage basin. Important elements include the water and energy cycle, climate variability and change, water management and extreme events, and related impacts on biogeochemical cycles. BALTEX was founded in 1993 as a GEWEX continental-scale experiment and is currently in its second 10 yr phase. Phase I (1993-2002) was primarily dedicated to hydrological, meteorological and oceanographic processes in the Baltic Sea drainage basin, hence mostly dealt with the physical aspects of the system. Scientific focus was on the hydrological cycle and the exchange of energy between the atmosphere, the Baltic Sea and the surface of its catchment. The BALTEX study area was hydrologically defined as the Baltic Sea drainage basin. The second 10 yr phase of BALTEX (Phase II: 2003-12) has strengthened regional climate research, water management issues, biogeochemical cycles and overarching efforts to reach out to stakeholders and decision makers, as well as to foster communication and education. Achievements of BALTEX Phase II have been the establishment of an assessment report of regional climate change and its impacts on the Baltic Sea basin (from hydrological to biological and socio-economic), the further development of regional physical climate models and the integration of biogeochemical and ecosystem models. BALTEX features a strong infrastructure, with an international secretariat and a publication series, and organizes various workshops and conferences. This article gives an overview of the BALTEX programme, with an emphasis on Phase II, with some examples from BALTEX-related research.

  4. Significance of archaeal nitrification in hypoxic waters of the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Berg, C.; Vandieken, V.; Thamdrup, B.; Jürgens, K.

    2012-04-01

    Marine oxygen deficient areas are sites of important microbially mediated transformations within the nitrogen cycle. In the Baltic Sea, suboxic waters (oxygen below 5 μmol L-1) are considered to be a major nitrification zone within the water column. Recent evidence indicates that Archaea and not Bacteria are here the major ammonium oxidizers. In a Baltic Sea pelagic redoxcline, the crenarchaeotal subcluster GD2 which is related to the first cultivated ammonia-oxidizing crenarchaeote Candidatus Nitrosopumilus maritimus occurs in high abundance. However, little is known about its function and importance for the nitrogen and carbon cycles in oxygen minimum zones of the Baltic Sea. To approach this question, we sampled pelagic redoxclines in the Baltic Sea and determined the rates of nitrification and light-independent, inorganic carbon fixation via 15N and 14C isotope incubations, and quantified the abundance of putative ammonia-oxidizing Crenarchaeota by catalyzed reporter deposition fluorescence in situ hybridization (CARD-FISH). Nitrification was detectable throughout the suboxic zone with maxima of 122-131 nmol L-1 d-1 in layers with 1.8-7.1 μmol oxygen L-1 and ammonium below 0.2 μmol L-1. However, a nitrification potential was detected even in the upper anoxic, sulfidic zone. Crenarchaeotal abundance correlated strongly with nitrification rates and accounted for up to 24% of total prokaryotic cells. In contrast, the CO2 fixation in the suboxic zone was with 1.6-19.6 nmol L-1 d-1 rather low when compared to the subjacent anoxic, sulfidic waters. Our study indicates that ammonia oxidation in the suboxic zone of the Baltic Sea is mainly driven by Crenarchaeota. Their occurrence also in the anoxic, sulfidic water masses and the maintained nitrification potential point to special adaptations in this habitat with a potentially reduced sensitivity against hydrogen sulfide.

  5. To what extent does the salinity flux influence phytoplankton blooms? - Baltic Sea modeling study

    NASA Astrophysics Data System (ADS)

    Cieszyńska, Agata; Stramska, Małgorzata

    2016-04-01

    This work is focused on numerical modeling of biological-physical interactions and their influence on phytoplankton production and vertical distribution of biomass and its variability in the surface waters of the Baltic Sea. The area of interest is an inland sea with water salinity much smaller than observed in the global ocean (about one fifth of the open ocean value). Vertical distribution of the salinity has a significant influence on water column density stratification, and therefore influences intensity of mixing and the depth of mixed layer. This, in turn, defines environmental conditions for phytoplankton growth. Vertical distribution of water salinity in the basin is controlled by processes such as evaporation/precipitation, freezing/melting of sea ice and runoff of freshwater from land. There are a lot of different phytoplankton species in the area of the Baltic Sea. Every single one has its own characteristics and is sensitive to distinct complex environmental conditions. Biological-physical interactions controlling these microorganisms' life cycles are multiplicitous and because of their complexity difficult to quantify. The best and probably only way to study presented issue is the usage of numerical modeling tool. The results presented here are based on 1D numerical simulations carried out with Princeton Ocean Model (POM, http://www.ccpo.odu.edu/POMWEB/) merged with the Ecological Regional Ecosystem Model (ERGOM, http://ergom.net/) developed for the Baltic Sea research by German scientists from the Leibniz Institute for Baltic Sea Research in Warnemünde. In model simulations surface salinity flux was determined from the difference between the precipitation and evaporation rate at the air-sea interface. Data for parameterization of atmospheric forcing were defined based on data sets from National Centers of Environmental Prediction (NCEP). We carried out systematic calculations using different values of surface fluxes encompassing the range of

  6. Ctenophore population recruits entirely through larval reproduction in the central Baltic Sea.

    PubMed

    Jaspers, Cornelia; Haraldsson, Matilda; Bolte, Sören; Reusch, Thorsten B H; Thygesen, Uffe H; Kiørboe, Thomas

    2012-10-23

    The comb jelly Mertensia ovum, widely distributed in Arctic regions, has recently been discovered in the northern Baltic Sea. We show that M. ovum also exists in the central Baltic but that the population consists solely of small-sized larvae (less than 1.6 mm). Despite the absence of adults, eggs were abundant. Experiments revealed that the larvae were reproductively active. Egg production and anticipated mortality rates suggest a self-sustaining population. This is the first account of a ctenophore population entirely recruiting through larval reproduction (paedogenesis). We hypothesize that early reproduction is favoured over growth to compensate for high predation pressure. PMID:22535640

  7. Ctenophore population recruits entirely through larval reproduction in the central Baltic Sea

    PubMed Central

    Jaspers, Cornelia; Haraldsson, Matilda; Bolte, Sören; Reusch, Thorsten B. H.; Thygesen, Uffe H.; Kiørboe, Thomas

    2012-01-01

    The comb jelly Mertensia ovum, widely distributed in Arctic regions, has recently been discovered in the northern Baltic Sea. We show that M. ovum also exists in the central Baltic but that the population consists solely of small-sized larvae (less than 1.6 mm). Despite the absence of adults, eggs were abundant. Experiments revealed that the larvae were reproductively active. Egg production and anticipated mortality rates suggest a self-sustaining population. This is the first account of a ctenophore population entirely recruiting through larval reproduction (paedogenesis). We hypothesize that early reproduction is favoured over growth to compensate for high predation pressure. PMID:22535640

  8. Legacy phosphorus in the Baltic Sea and implications for reversing eutrophication

    NASA Astrophysics Data System (ADS)

    McCrackin, M. L.; Gustafsson, B.; Humborg, C.; Hong, B.; Svanbäck, A.; Swaney, D. P.; Viktorsson, L.

    2015-12-01

    Eutrophication has depleted concentrations of dissolved oxygen in bottom waters of the Baltic Sea, resulting in the world's largest "dead" zone. A number of measures have been implemented to reduce nutrient inputs and, indeed, between 1995 and 2012 phosphorus (P) loads to the sea deceased 19%. The long-term accumulation and subsequent release of P from both the catchment and marine sediments combined with 30-year water residence times could significantly delay recovery from eutrophication. We estimated net P accumulation (legacy P) for the Baltic Sea using the Net Anthropogenic Phosphorus Inputs (NAPI) approach and historical records of food and feed trade and riverine fluxes. Net P inputs to the catchment peaked at 0.7 million tons per year during the 1970's and since the political and economical changes in Eastern Europe during the 1990's, decreased to 0.2-0.3 million tons per year. P accumulation on land is ten times greater than accumulation in the sea (20 million and 2 million tons, respectively). Of the P retained on land, the majority (18-19 million tons) is in agricultural lands, with the balance in lake sediments. Of the 2 million tons in the sea, two-thirds are in sediments and one-third in the water column. The success of nutrient management actions in reducing river nutrient fluxes will lead to improvement in the Baltic Sea environment, but the massive accumulation of P on land will complicate efforts to achieve complete recovery.

  9. Plastic ingestion by pelagic and demersal fish from the North Sea and Baltic Sea.

    PubMed

    Rummel, Christoph D; Löder, Martin G J; Fricke, Nicolai F; Lang, Thomas; Griebeler, Eva-Maria; Janke, Michael; Gerdts, Gunnar

    2016-01-15

    Plastic ingestion by marine biota has been reported for a variety of different taxa. In this study, we investigated 290 gastrointestinal tracts of demersal (cod, dab and flounder) and pelagic fish species (herring and mackerel) from the North and Baltic Sea for the occurrence of plastic ingestion. In 5.5% of all investigated fishes, plastic particles were detected, with 74% of all particles being in the microplastic (<5mm) size range. The polymer types of all found particles were analysed by means of Fourier transform infrared (FT-IR) spectroscopy. Almost 40% of the particles consisted of polyethylene (PE). In 3.4% of the demersal and 10.7% of the pelagic individuals, plastic ingestion was recorded, showing a significantly higher ingestion frequency in the pelagic feeders. The condition factor K was calculated to test differences in the fitness status between individuals with and without ingested plastic, but no direct effect was detected.

  10. Preparations to use Synthetic Aperture Radar (SAR) in sea ice remote sensing in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Leppäranta, M.; Kuittinen, R.; Kemppainen, H.

    Remote sensing methods are largely used in ice mapping in the Baltic Sea. The next significant step will come true in next decade with satellite Synthetic Aperture Radars (SAR); in particular, SAR is weather independent and provides information of ice roughness. As an early phase of a joint Finnish-Swedish research programme BEPERS (Bothnian Experiment in Preparation for ERS-1), a field experiment ``BEPERS Pilot Study'' was carried through in 1987. The French VARAN-S X-band SAR was chartered for this experiment. Four study areas of around 10 × 50 km size were chosen representing different ice types and conditions. Intensive ground and remote sensing observations were made for correct interpretation of the SAR images. Digital analyses of the SAR images showed that the ice cover could be classified into four classes: 1) open water or bare smooth ice, 2) smooth of slightly deformed ice, 3) ridges and 4) leads with brash ice.

  11. Anatomizing one of the largest saltwater inflows into the Baltic Sea in December 2014

    NASA Astrophysics Data System (ADS)

    Gräwe, Ulf; Naumann, Michael; Mohrholz, Volker; Burchard, Hans

    2015-11-01

    In December 2014, an exceptional inflow event into the Baltic Sea was observed, a so-called Major Baltic Inflow (MBI). Such inflow events are important for the deep water ventilation in the Baltic Sea and typically occur every 3-10 years. Based on first observational data sets, this inflow had been ranked as the third largest since 100 years. With the help of a multinested modeling system, reaching from the North Atlantic (8 km resolution) to the Western Baltic Sea (600 m resolution, which is baroclinic eddy resolving), this event is reproduced in detail. The model gave a slightly lower salt transport of 3.8 Gt, compared to the observational estimate of four Gt. Moreover, by using passive tracers to mark the different inflowing water masses, including an age tracer, the inflowing water masses could be tracked and their paths and timing through the different basins could be reproduced and investigated. The analysis is supported by the recently developed Total Exchange Flow (TEF) to quantify the volume transport in different salinity classes. To account for uncertainties in the modeled velocity and tracer fields, a Monte Carlo Analysis (MCA) is applied to correct possible biases and errors. With the help of the MCA, 95% confidence intervals are computed for the transport estimates. Based on the MCA, the "best guess" of the volume transport is 291.0 ± 13.65 km3 and 3.89 ± 0.18 Gt for the total salt transport.

  12. Anomalous secular sea-level acceleration in the Baltic Sea caused by glacial isostatic adjustment

    NASA Astrophysics Data System (ADS)

    Spada, Giorgio; Galassi, Gaia; Olivieri, Marco

    2014-05-01

    Observations from the global array of tide gauges show that global sea-level has been rising at an average rate of 1.5-2 mm/yr during the last ˜ 150 years (Spada & Galassi, 2012). Although a global sea-level acceleration was initially ruled out, subsequent studies have coherently proposed values of ˜1 mm/year/century (Olivieri & Spada, 2012). More complex non-linear trends and abrupt sea-level variations have now also been recognized. Globally, they could manifest a regime shift between the late Holocene and the current rhythms of sea-level rise, while locally they result from ocean circulation anomalies, steric effects and wind stress (Bromirski et al. 2011). Although isostatic readjustment affects the local rates of secular sea-level change, a possible impact on regional acceleration have been so far discounted (Woodworth et al., 2009) since the process evolves on a millennium scale. Here we report a previously unnoticed anomaly in the long-term sea-level acceleration of the Baltic Sea tide gauge records, and we explain it by the classical post-glacial rebound theory and numerical modeling of glacial isostasy. Contrary to previous assumptions, our findings demonstrate that isostatic compensation plays a role in the regional secular sea-level acceleration. In response to glacial isostatic adjustment (GIA), tide gauge records located along the coasts of the Baltic Sea exhibit a small - but significant - long-term sea-level acceleration in excess to those in the far field of previously glaciated regions. The sign and the amplitude of the anomaly is consistent with the post-glacial rebound theory and with realistic numerical predictions of GIA models routinely employed to decontaminate the tide gauges observations from the GIA effects (Peltier, 2004). Model computations predict the existence of anomalies of similar amplitude in other regions of the globe where GIA is still particularly vigorous at present, but no long-term instrumental observations are available to

  13. Iceberg ploughmark features on bottom surface of the South-Eastern Baltic Sea

    NASA Astrophysics Data System (ADS)

    Dorokhov, Dmitry; Sivkov, Vadim; Dorokhova, Evgenia; Krechik, Viktor

    2016-04-01

    A detail swath bathymetry, side-scan sonar and acoustic profiling combined with sediment sampling during the 64th cruise of RV "Academic Mstislav Keldysh" (October 2015) allowed to identify new geomorphological features of the South-Eastern Baltic Sea bottom surface. The extended chaotic ploughmarks (furrows) in most cases filled with thin layer of mud were discovered on surface of the Gdansk-Gotland sill glacial deposits. They are observed on the depth of more than 70 m and have depth and width from 1 to 10 m. Most of them are v- or u-shaped stepped depressions. The side-scan records of similar geomorpholoical features are extensively reported from Northern Hemisphere and Antarctica (Goodwin et al., 1985; Dowdeswell et al., 1993). Ploughmarks are attributed to the action of icebergs scouring into the sediment as they touch bottom. We are suggest that furrows discovered in the South-Eastern Baltic Sea are also the result of iceberg scouring during the Baltic Ice Lake stage (more than 11 600 cal yr BP (Bjorck, 2008)). This assumption confirmed by occurrence of fragmental stones and boulders on the sea bottom surface which are good indicators of iceberg rafting (Lisitzin, 2003). Ice ploughmarks at sea bottom surface were not occurred before in the South-Eastern Baltic Sea. The study was financed by Russian Scientific Fund, grant number 14-37-00047. References Bjorck S. The late Quaternary development of the Baltic Sea Basin. In: The BACC Author Team (eds) Assessment of climate change for the Baltic Sea Basin. Springer, Berlin, Heidelberg. 2008. Dowdeswell J. A., Villinger H., Whittington R. J., Marienfeld P. Iceberg scouring in Scoresby Sund and on the East Greenland continental shelf // Marine Geology. V. 111. N. 1-2. 1993. P. 37-53. Goodwin C. R., Finley J. C., Howard L. M. Ice scour bibliography. Environmental Studies Revolving Funds Report No. 010. Ottawa. 1985. 99 pp. Lisitzin A. P. Sea-Ice and Iceberg Sedimentation in the Ocean: Recent and Past. Springer

  14. What can ARGO's tell us on the processes in Baltic Sea?

    NASA Astrophysics Data System (ADS)

    Roiha, Petra; Siiriä, Simo-Matti; Nummelin, Aleksi; Aro, Eemeli; Purokoski, Tero

    2014-05-01

    Finnish Meteorological Institute has been testing ARGO floats in the Baltic Sea as a mean for collecting data from the sea areas that are not easily reachable by research vessels or remote sensing. The observational data for Baltic Sea off-shore areas is very sparse and new observational methods are needed to fill the gaps in our knowledge and collect new data for different purposes, such as, operational activities, modelling and ocean science. The ARGO floats have been used successfully in the deep oceans. However, applying the ARGO floats in Baltic Sea is not straight forward, as the conditions differ greatly: the water is brackish, some areas are heavily trafficked and the northern parts freeze during the winter. In addition, the mean depth is only 54 metres, which is only a fraction of depths where ARGO floats have commonly been used. FMI has deployed three ARGO floats in Baltic Sea for different missions. The first ARGO was deployed in 2012 with normal diving algorithm, which checks the pressure hourly. The second float was modified by Aalto University so that the algorithm checks the pressure every 15 minutes. The first float was deployed in the Bothnian Sea in May 2013 and it measured over 200 profiles during its half year mission. The float with faster pressure detection was deployed in the Bothnian Sea in May 2013, and during it's 4 month mission it measured succesfully over 120 profiles. Another, longer test is ongoing on Eastern Gotland basin, where another ARGO float was deployed at Aug 2013, and still measures at Jan 2014. This one differs from earlier experiments as it has additional oxygen and scattering meters, also the area of measurements is deeper (200+ meters). The missions so far indicate, that with proper control and monitoring, ARGO's can be operated, and can measure long series of profiles. In addition to the actual measurements, the movement of ARGO floats gives possibilities to analyse currents in deeper areas of Baltic, and help

  15. Towards The Operational Oceanographic Model System In Estonian Coastal Sea, Baltic Sea

    NASA Astrophysics Data System (ADS)

    Kõuts, T.; Elken, J.; Raudsepp, U.

    An integrated system of nested 2D and 3D hydrodynamic models together with real time forcing data asquisition is designed and set up in pre-operational mode in the Gulf of Finland and Gulf of Riga, the Baltic Sea. Along the Estonian coast, implicit time-stepping 3D models are used in the deep bays and 2D models in the shallow bays with ca 200 m horizontal grid step. Specific model setups have been verified by in situ current measurements. Optimum configuration of initial parameters has been found for certain critical locations, usually ports, oil terminals, etc. Operational system in- tegrates also section of historical database of most important hydrologic parameters in the region, allowing use of certain statistical analysis and proper setup of initial conditions for oceanographic models. There is large variety of applications for such model system, ranging from environmental impact assessment at local coastal sea pol- lution problems to forecast of offshore blue algal blooms. Most probable risk factor in the coastal sea engineering is oil pollution, therefore current operational model sys- tem has direct custom oriented output the oil spill forecast for critical locations. Oil spill module of the operational system consist the automatic weather and hydromet- ric station (distributed in real time to internet) and prognostic model of sea surface currents. System is run using last 48 hour wind data and wind forecast and estimates probable oil deposition areas on the shoreline under certain weather conditions. Cal- culated evolution of oil pollution has been compared with some real accidents in the past and there was found good agreement between model and measurements. Graphi- cal user interface of oil spill model is currently installed at location of port authorities (eg. Muuga port), so in case of accidents it could be used in real time supporting the rescue operations. In 2000 current pre-operational oceanographic model system has been sucessfully used to

  16. Sensitivity of modeled atmospheric nitrogen species to variations in sea salt emissions in the North and Baltic Sea regions

    NASA Astrophysics Data System (ADS)

    Neumann, D.; Matthias, V.; Bieser, J.; Aulinger, A.; Quante, M.

    2015-10-01

    Coarse sea salt particles are emitted ubiquitously from the oceans' surfaces by wave breaking and bubble bursting processes. These particles impact atmospheric chemistry by affecting condensation of gas-phase species and nucleation of new fine particles, particularly in regions with high air pollution. In this study, atmospheric particle concentrations are modeled for the North and Baltic Sea regions, Northwestern Europe, using the Community Multiscale Air Quality (CMAQ) modeling system and evaluated against European Monitoring and Evaluation Programme (EMEP) measurement data. As model extension, sea salt emissions are scaled by water salinity because of low salinity in large parts of the Baltic Sea and in certain river estuaries. The resulting improvement in predicted sea salt concentrations is assessed. The contribution of surf zone emissions is separately considered. Additionally, the impact of sea salt particles on atmospheric nitrate, ammonium and sulfate concentrations is evaluated. The comparisons show that sea salt concentrations are commonly overestimated at coastal stations and partly underestimated when going inland. The introduced salinity scaling improves predicted Baltic Sea sea salt concentrations considerably. Dates of measured peak concentrations are appropriately reproduced by the model. The impact of surf zone emissions is negligible in both seas. Nevertheless, they might be relevant because surf zone emissions were cut at an upper threshold in this study. Deactivating sea salt leads to a minor increase of NH4+ and NO3- and a minor decrease of SO42- concentrations. However, the overall effect is very low and lower than the deviation from measurements. Size resolved measurements of Na+, NH4+, NO3-, and SO42- are needed for a more detailed analysis on the impact of sea salt particles.

  17. Role of sea-ice biota in nutrient and organic material cycles in the northern Baltic Sea.

    PubMed

    Kuparinen, Jorma; Kuosa, Harri; Andersson, Agneta; Autio, Riitta; Granskog, Mats A; Ikävalko, Johanna; Kaartokallio, Hermanni; Karell, Kimmo; Leskinen, Elina; Piiparinen, Jonna; Rintala, Janne-Markus; Tuomainen, Jaana

    2007-04-01

    This paper compiles biological and chemical sea-ice data from three areas of the Baltic Sea: the Bothnian Bay (Hailuoto, Finland), the Bothnian Sea (Norrby, Sweden), and the Gulf of Finland (Tvärminne, Finland). The data consist mainly of field measurements and experiments conducted during the BIREME project from 2003 to 2006, supplemented with relevant published data. Our main focus was to analyze whether the biological activity in Baltic Sea sea-ice shows clear regional variability. Sea-ice in the Bothnian Bay has low chlorophyll a concentrations, and the bacterial turnover rates are low. However, we have sampled mainly land-fast level first-year sea-ice and apparently missed the most active biological system, which may reside in deformed ice (such as ice ridges). Our limited data set shows high concentrations of algae in keel blocks and keel block interstitial water under the consolidated layer of the pressure ridges in the northernmost part of the Baltic Sea. In land-fast level sea-ice in the Bothnian Sea and the Gulf of Finland, the lowermost layer appears to be the center of biological activity, though elevated biomasses can also be found occasionally in the top and interior parts of the ice. Ice algae are light limited during periods of snow cover, and phosphate is generally the limiting nutrient for ice bottom algae. Bacterial growth is evidently controlled by the production of labile dissolved organic matter by algae because low growth rates were recorded in the Bothnian Bay with high concentrations of allochthonous dissolved organic matter. Bacterial communities in the Bothnian Sea and the Gulf of Finland show high turnover rates, and activities comparable with those of open water communities during plankton blooms, which implies that sea-ice bacterial communities have high capacity to process matter during the winter period.

  18. Processes relevant for decadal changes in primary production of the North Sea and Baltic Sea: hindcast and scenario modelling

    NASA Astrophysics Data System (ADS)

    Daewel, Ute; Schrum, Corinna; Pushpadas, Dhanya

    2016-04-01

    Despite their geographical vicinity, the North Sea and the Baltic Sea ecosystems exhibit very different characteristics in both physical and biological parameters. Nonetheless, since both ecosystems are characterized by the same general functional groups in phytoplankton and zooplankton and, their geographical distribution indicates comparable thermal adaptation of the plankton groups, we propose that the same ecosystem parameterization can be utilized to simulate the dynamics in both ecosystems simultaneously. Here we present results from an updated version of the 3d coupled ecosystem model ECOSMO valid for both areas. The model allows both multi-decadal hind cast simulation of primary production and specific process studies under controlled environmental conditions. Our results from a long-term hind-cast (1948-2008) indicate incoherent "regime shifts" in the primary productivity (PP) between the North Sea and Baltic Sea. Correlation analysis between atmospheric forcing and PP indicates significant correlations for both solar radiation and wind but cannot serve to identify causal relationship. Therefore additional scenario tests with perturbations in individual atmospheric condition where accomplished emphasizing specifically the role of solar radiation, wind and eutrophication. The results revealed that, although all parameters are relevant for the PP in North Sea and Baltic Sea, the dominant impact on long term variability was introduced by modulations of the wind fields.

  19. Infusorians as a component of the planktonic community in the Baltic Sea

    SciTech Connect

    Mamaeva, N.V.

    1985-09-01

    The authors' investigations of infusorians as a component of the planktonic community in the Baltic Sea coincided with the heterotrophic stage of seasonal succession, and as a result the infusorians were numerous. In the deep troughs of the Sea at a depth of more than 150 m, the water is saturated with hydrogen sulfide. A community of infusorians relating to the saprobionts and capable of living with the minimal amount of oxygen was discovered for the first time--in the upper boundary of the hydrogen sulfide zone. In its level of infusorian abundance, the Baltic Sea must be considered a eutrophic body of water where infusorians serve as one of the leading agents in its self-purification.

  20. The Ancylus Lake stage of the Baltic Sea in Fehmarn Belt: Indications of a new threshold?

    NASA Astrophysics Data System (ADS)

    Feldens, Peter; Schwarzer, Klaus

    2012-03-01

    The Baltic Ice Lake, Yoldia Sea, Ancylus Lake and Littorina Sea stages of regression and transgression controlled the history of the Baltic Sea since the last glacial period. Many details regarding their development remain unknown, including the question whether the regression of the Ancylus Lake (between 10,700 and 10,200 cal yr BP) took place west of the Darss Sill, or elsewhere. This study addresses whether a drowned river system in Fehmarn Belt (SW Baltic Sea) can be related to the drainage of the Ancylus Lake. The river channel is cut into glacial till in the western part of Fehmarn Belt. Here, the channel reaches an incision depth of up to 12 m at a base level of 40 m b.s.l. (below sea level). Near Mecklenburg Bay, the buried channel is incised down to 60 m b.s.l. and widens rapidly from several hundred meters to more than 1 km, fading towards east. It was mainly shaped as part of a glacial meltwater system at a maximum water level of 30 m b.s.l., and is therefore not related to the Ancylus Lake drainage. During the lowstand of the Baltic Ice Lake, local shallow water bodies covered the study area. A previously reported westward directed drainage of a lake in the eastern Fehmarn Belt could be restricted to a time interval between the highstand of the Ancylus Lake and prior to the Littorina Transgression. Timing, water level and potential water discharge of this event suggest a connection to a partial drainage of the Ancylus Lake. It is concluded that the threshold separating the Ancylus Lake from the North Sea needs to be located west of Fehmarn Belt.

  1. Chemical characterization of dissolved organic compounds from coastal sea surface microlayers (Baltic Sea, Germany).

    PubMed

    van Pinxteren, Manuela; Müller, Conny; Iinuma, Yoshiteru; Stolle, Christian; Herrmann, Hartmut

    2012-10-01

    The physicochemical properties of the sea surface microlayer (SML), i.e. the boundary layer between the air and the sea, and its impact on air-sea exchange processes have been investigated for decades. However, a detailed description about these processes remains incomplete. In order to obtain a better chemical characterization of the SML, in a case study three pairs of SML and corresponding bulk water samples were taken in the southern Baltic Sea. The samples were analyzed for dissolved organic carbon and dissolved total nitrogen, as well as for several organic nitrogen containing compounds and carbohydrates, namely aliphatic amines, dissolved free amino acids, dissolved free monosaccharides, sugar alcohols, and monosaccharide anhydrates. Therefore, reasonable analytical procedures with respect to desalting and enrichment were established. All aliphatic amines and the majority of the investigated amino acids (11 out of 18) were found in the samples with average concentrations between 53 ng L(-1) and 1574 ng L(-1). The concentrations of carbohydrates were slightly higher, averaging 2900 ng L(-1). Calculation of the enrichment factor (EF) between the sea surface microlayer and the bulk water showed that dissolved total nitrogen was more enriched (EF: 1.1 and 1.2) in the SML than dissolved organic carbon (EF: 1.0 and 1.1). The nitrogen containing organic compounds were generally found to be enriched in the SML (EF: 1.9-9.2), whereas dissolved carbohydrates were not enriched or even depleted (EF: 0.7-1.2). Although the investigated compounds contributed on average only 0.3% to the dissolved organic carbon and 0.4% to the total dissolved nitrogen fraction, these results underline the importance of single compound analysis to determine SML structure, function, and its potential for a transfer of compounds into the atmosphere. PMID:22475414

  2. Content of strontium-90 and cesium-137 in a number of regions of the Baltic Sea in 1982

    SciTech Connect

    Lazarev, L.N.; Flegontov, V.M.; Gedenov, L.I.; Ivanova, L.M.; Orlova, T.B.; Stepanov, A.V.

    1985-07-01

    The authors present the data gathered from the samples of water and bed deposits taken at various sites in the Baltic Sea, the Gulf of Riga, and the Gulf of Finland. By means of the radiochemical method using ferrocyanide-carbonate concentration, they determine strotium-90 and cesium-137 content. The authors conclude by noting an increase in the cesium-137 content in the deep waters of the Baltic Sea and in bed deposits, and by cautioning that this development commands close attention.

  3. Recent trends and variations in Baltic Sea temperature, salinity, stratification and circulation

    NASA Astrophysics Data System (ADS)

    Elken, Jüri; Lehmann, Andreas; Myrberg, Kai

    2015-04-01

    The presentation highlights the results of physical oceanography from BACC II (Second BALTEX Assessment of Climate Change for the Baltic Sea basin) book based on the review of recent literature published until 2013. We include also information from some more recent publications. A recent warming trend in sea surface waters has been clearly demonstrated by all available methods: in-situ measurements, remote sensing data and modelling tools. In particular, remote sensing data for the period 1990-2008 indicate that the annual mean SST has increased even by 1°C per decade, with the greatest increase in the northern Bothnian Bay and also with large increases in the Gulf of Finland, the Gulf of Riga, and the northern Baltic Proper. Although the increase in the northern areas is affected by the recent decline in the extent and duration of sea ice, and corresponding changes in surface albedo, warming is still evident during all seasons and with the greatest increase occurring in summer. The least warming of surface waters (0.3-0.5°C per decade) occurred northeast of Bornholm Island up to and along the Swedish coast, probably owing to an increase in the frequency of coastal upwelling forced by the westerly wind events. Comparing observations with the results of centennial-scale modelling, recent changes in sea water temperature appear to be within the range of the variability observed during the past 500 years. Overall salinity pattern and stratification conditions are controlled by river runoff, wind conditions, and salt water inflows through the Danish straits. The mean top-layer salinity is mainly influenced by the accumulated river runoff, with higher salinity during dry periods and lower salinity during wet periods. Observations reveal a low-salinity period above the halocline starting in the 1980s. The strength of stratification and deep salinity are reduced when the mean zonal wind stress increases, as it occurred since 1987. Major Baltic Inflows of highly saline

  4. Large spatial variations in coastal 14C reservoir age - a case study from the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Lougheed, B. C.; Filipsson, H. L.; Snowball, I.

    2013-05-01

    Coastal locations are highly influenced by input from freshwater river runoff, including sources of terrestrial carbon, which can be expected to modify the 14C reservoir age, or R (t), associated with marine water. In this Baltic Sea case study, pre-bomb museum collection mollusc shells of known calendar age, from 30 locations across a strategic salinity transect of the Baltic Sea, were analysed for 14C, δ13C and δ18O. R (t) was calculated for all 30 locations. Seven locations, of which six are within close proximity of the coast, were found to have relatively higher R (t) values, indicative of hard-water effects. Whenever possible, the Macoma genus of mollusc was selected from the museum collections, in order to exclude species specific reservoir age effects as much as possible. When the Macoma samples are exclusively considered, and samples from hard-water locations excluded, a statistically significant correlation between Macoma R (t) and average salinity is found, indicating a two end-member linear mixing model between 14Cmarine and 14Crunoff. A map of Baltic Sea Macoma aragonite R (t) for the late 19th and early 20th centuries is produced. Such a map can provide an estimate for contemporary Baltic Sea Macoma R (t), although one must exercise caution when applying such estimates back in time or to 14C dates obtained from different sample material. A statistically significant correlation is found between δ18Oaragonite and Macoma R (t), suggesting that δ18Oaragonite can be used to estimate Macoma palaeo-R (t), due to the δ18Oaragonite signal being dominated by the salinity gradient of the Baltic Sea. A slightly increased correlation can be expected when δ18Oaragonite is corrected for temperature fractionation effects. The results of this Baltic Sea case study, which show that R (t) is affected by hydrographic conditions and local carbon inputs, have important consequences for other coastal and estuarine locations, where R (t) is also likely to significantly

  5. Divergence within and among Seaweed Siblings (Fucus vesiculosus and F. radicans) in the Baltic Sea

    PubMed Central

    Ardehed, Angelica; Johansson, Daniel; Sundqvist, Lisa; Schagerström, Ellen; Zagrodzka, Zuzanna; Kovaltchouk, Nikolaj A.; Bergström, Lena; Kautsky, Lena; Rafajlovic, Marina; Pereyra, Ricardo T.

    2016-01-01

    Closely related taxa provide significant case studies for understanding evolution of new species but may simultaneously challenge species identification and definition. In the Baltic Sea, two dominant and perennial brown algae share a very recent ancestry. Fucus vesiculosus invaded this recently formed postglacial sea 8000 years ago and shortly thereafter Fucus radicans diverged from this lineage as an endemic species. In the Baltic Sea both species reproduce sexually but also recruit fully fertile new individuals by asexual fragmentation. Earlier studies have shown local differences in morphology and genetics between the two taxa in the northern and western Bothnian Sea, and around the island of Saaremaa in Estonia, but geographic patterns seem in conflict with a single origin of F. radicans. To investigate the relationship between northern and Estonian distributions, we analysed the genetic variation using 9 microsatellite loci in populations from eastern Bothnian Sea, Archipelago Sea and the Gulf of Finland. These populations are located in between earlier studied populations. However, instead of bridging the disparate genetic gap between N-W Bothnian Sea and Estonia, as expected from a simple isolation-by-distance model, the new populations substantially increased overall genetic diversity and showed to be strongly divergent from the two earlier analysed regions, showing signs of additional distinct populations. Contrasting earlier findings of increased asexual recruitment in low salinity in the Bothnian Sea, we found high levels of sexual reproduction in some of the Gulf of Finland populations that inhabit extremely low salinity. The new data generated in this study supports the earlier conclusion of two reproductively isolated but very closely related species. However, the new results also add considerable genetic and morphological complexity within species. This makes species separation at geographic scales more demanding and suggests a need for more

  6. Divergence within and among Seaweed Siblings (Fucus vesiculosus and F. radicans) in the Baltic Sea.

    PubMed

    Ardehed, Angelica; Johansson, Daniel; Sundqvist, Lisa; Schagerström, Ellen; Zagrodzka, Zuzanna; Kovaltchouk, Nikolaj A; Bergström, Lena; Kautsky, Lena; Rafajlovic, Marina; Pereyra, Ricardo T; Johannesson, Kerstin

    2016-01-01

    Closely related taxa provide significant case studies for understanding evolution of new species but may simultaneously challenge species identification and definition. In the Baltic Sea, two dominant and perennial brown algae share a very recent ancestry. Fucus vesiculosus invaded this recently formed postglacial sea 8000 years ago and shortly thereafter Fucus radicans diverged from this lineage as an endemic species. In the Baltic Sea both species reproduce sexually but also recruit fully fertile new individuals by asexual fragmentation. Earlier studies have shown local differences in morphology and genetics between the two taxa in the northern and western Bothnian Sea, and around the island of Saaremaa in Estonia, but geographic patterns seem in conflict with a single origin of F. radicans. To investigate the relationship between northern and Estonian distributions, we analysed the genetic variation using 9 microsatellite loci in populations from eastern Bothnian Sea, Archipelago Sea and the Gulf of Finland. These populations are located in between earlier studied populations. However, instead of bridging the disparate genetic gap between N-W Bothnian Sea and Estonia, as expected from a simple isolation-by-distance model, the new populations substantially increased overall genetic diversity and showed to be strongly divergent from the two earlier analysed regions, showing signs of additional distinct populations. Contrasting earlier findings of increased asexual recruitment in low salinity in the Bothnian Sea, we found high levels of sexual reproduction in some of the Gulf of Finland populations that inhabit extremely low salinity. The new data generated in this study supports the earlier conclusion of two reproductively isolated but very closely related species. However, the new results also add considerable genetic and morphological complexity within species. This makes species separation at geographic scales more demanding and suggests a need for more

  7. A 35-year hindcast for the Baltic Sea (1980-2014) - a statistical analysis

    NASA Astrophysics Data System (ADS)

    Gräwe, Ulf; Holtermann, Peter

    2015-04-01

    The Baltic Sea is a semi-enclosed sea with limited water exchange. The most important process that leads to deep water renewal of the Baltic Sea are inflows of dense, saline North Sea water. These water masses have to pass narrow channels and sills in the Danish Straits and three basins with increasing depth. Along this path, the inflowing gravity currents are subject to entrainment, vertical and horizontal mixing. Thus, physical and numerical mixing are crucial for the proper propagation of these inflows. Additionally, a permanent halocline and a summer thermocline are challenging for state of the art ocean models. Moreover, Holtermann et al (2014) could show, that boundary mixing in the deep basins dominates the vertical mixing of tracers. To tackle these challenges, we used the General Estuarine Transport Model (GETM) to give a state estimate for the Baltic Sea for the period 1980-2014. The setup has a horizontal resolution of 1 nm. In the vertical, terain following coordinates are used. A special feature of GETM is that it can run with vertical adaptive coordinates. Here we use an adaptation towards stratification. The minimum layer thickness is limited to 30 cm. We also include the effects of wind waves (by radiation stresses, and changes in the bottom stresses) into our simulations. The atmospheric forcing is taken from the global reanalysis of the NCEP-CFSR (Saha et al 2011) with a spatial resolution of 30 km and hourly values. The model validation at selected stations in the Baltic Sea shows an average Bias of ±0.15 psu and a RMSE of 0.4 psu. These values are similar to the data assimilation runs of Fu et al (2011) or Liu et al (2013). However, one has to note that our simulations are free runs without any nudging or data assimilation. Driven by the good performance of the model, we use the model output to provide a state estimate of the actual climate period (1980-2010). The analysis includes a quantification and estimation of: surge levels with a 30-year

  8. Turbulence structure of the marine stable boundary layer over the Baltic Sea

    SciTech Connect

    Smedman, A.S.; Hoegstroem, U.

    1994-12-31

    For more than half of the year the land surfaces surrounding the Baltic Sea is warmer than the sea surface, and the marine boundary layer over the Baltic is stable. Observations, at various sites in the Baltic Sea area during the last decade. also indicate frequent occurrence of low-level jets at the top of the stable boundary layer. In many cases the marine jet can be considered as an analogy in space to the evolution of the nocturnal jet with time. The frictional decoupling occurs when warm air over the land is flowing out over the sea. Data from two areas together with model simulations are used in this study to characterize turbulence structure in the marine boundary layer. The measurements include profiles of wind and temperature on towers situated at two isolated islands, together with turbulence recordings and aircraft measurements. Also wave height and water surface temperature have been measured. The model simulations are performed with a second-order closure model.

  9. Baltic Sea Gastrotricha--one new species and one new record of Chaetonotida from Poland.

    PubMed

    Kolicka, Małgorzata; Jankowska, Emilia; Kotwicki, Lech

    2015-01-01

    Gastrotricha is a cosmopolitan phylum of aquatic and semi-aquatic invertebrates that comprise about 820 described species, which are divided into two orders: Chaetonotida Remane, 1925 [Rao & Clausen, 1970] and Macrodasyida Remane, 1925 [Rao & Clausen, 1970]. They inhabit natural as well as artificial habitats in diverse marine, freshwater, and semi-aquatic ecosystems (e.g. peatbogs, alder woods, riparian forests). Until now, 29 species of gastrotrichs from the Polish Baltic Sea region (including three freshwater species which were found in estuaries) were known. Sixteen species belong to Chaetonotida and thirteen to Macrodasyida. During this study we found two species, Heterolepidoderma sinus spec. nov., and Aspidiophorus lamellophorus Balsamo, Hummon, Todaro et Tongiorgi, 1997 which is new to the Baltic Sea fauna. H. sinus spec. nov. has distinct cuticular reinforcements in the anterior dilatation of the pharynx. Moreover, it is characterized by two kinds of lamellae: one type is represented by small triangular lamellae which aris from lateral scales, the second type is large and clearly visible and arises from ventral scales. None of the Heterolepidoderma species known so far has two types of lamellae. A. lamellophorus was previously known only from the Mediterranean Sea. The finding of two new gastrotrich species in the Baltic Sea shows that the knowledge of these small invertebrates in the area is still far from complete. PMID:26624193

  10. Tracking the migratory success of stocked European eels Anguilla anguilla in the Baltic Sea.

    PubMed

    Prigge, E; Marohn, L; Hanel, R

    2013-02-01

    To investigate the extent to which European silver eels Anguilla anguilla, originating from stocking programmes in the Baltic Sea tributaries, effectively contribute to the spawning stock, two hundred and seventy-four formerly stocked A. anguilla. emigrating from the Schwentine River near Kiel, Germany, were tagged with T-Bar anchor tags. A total of 29 Anguilla spp. were recaptured (c. 11%) up to 14 months after release. Stocking history of recaptured A. anguilla. was confirmed by otolith microchemistry. Recapture locations were concentrated around the outlet of the Baltic Sea (Danish Belt Sea) with 62% of all recaptures reported here or in the Kattegat. Recaptured Anguilla spp. showed a reduction in both L(T) and mass (mean ± s.d. = -1.5 ± 0.9 cm and -125.3 ± 50.1 g) while average total fat content remained in the order of values previously reported as high enough to provide energy resources to allow successful completion of the spawning migration (mean ± s.d. = 28.4 ± 4.4%). The documented mean rate of travel (0.8 km day(-1)), however, indicated a delay in the target-oriented migration that might be interpreted as a delayed initial migration phase of orientation towards the exit of the Baltic Sea.

  11. The hydrodynamic part of the 3D CEMBS model for the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Dzierzbicka-Glowacka, Lidia; Jakacki, Jaromir; Janecki, Maciej; Nowicki, Artur

    2013-04-01

    The paper presents a hydrodynamic part of the coupled ice-ocean model 3D CEMBS designed for the Baltic Sea. It is based on the Community Earth System Model (CESM from the National Center for Atmospheric Research). It was adopted for the Baltic Sea as a coupled sea-ice model. It consists of the Community Ice Code (CICE model, version 4.0) and the Parallel Ocean Program (version 2.1). The models are linked through the coupler (CPL7) based on the Model Coupling Toolkit library. The ocean model has 21 vertical levels and horizontal grid of 600x640 cells. Horizontal resolution is approximately 2km. It is forced by atmospheric fields from European Centre for Medium-Range Weather Forecasts and in operational mode from 48-hour atmospheric forecasts provided by the UM model from the Interdisciplinary Centre for Mathematical and Computational Modelling of Warsaw University (ICM). The study was financially supported by the Polish State Committee of Scientific Research (grants: No N N305 111636, N N306 353239). The partial support for this study was also provided by the project Satellite Monitoring of the Baltic Sea Environment - SatBaltyk founded by European Union through European Regional Development Fund contract no. POIG 01.01.02-22-011/09. Calculations were carried out at the Academy Computer Centre in Gdansk.

  12. Baltic Sea Gastrotricha--one new species and one new record of Chaetonotida from Poland.

    PubMed

    Kolicka, Małgorzata; Jankowska, Emilia; Kotwicki, Lech

    2015-10-06

    Gastrotricha is a cosmopolitan phylum of aquatic and semi-aquatic invertebrates that comprise about 820 described species, which are divided into two orders: Chaetonotida Remane, 1925 [Rao & Clausen, 1970] and Macrodasyida Remane, 1925 [Rao & Clausen, 1970]. They inhabit natural as well as artificial habitats in diverse marine, freshwater, and semi-aquatic ecosystems (e.g. peatbogs, alder woods, riparian forests). Until now, 29 species of gastrotrichs from the Polish Baltic Sea region (including three freshwater species which were found in estuaries) were known. Sixteen species belong to Chaetonotida and thirteen to Macrodasyida. During this study we found two species, Heterolepidoderma sinus spec. nov., and Aspidiophorus lamellophorus Balsamo, Hummon, Todaro et Tongiorgi, 1997 which is new to the Baltic Sea fauna. H. sinus spec. nov. has distinct cuticular reinforcements in the anterior dilatation of the pharynx. Moreover, it is characterized by two kinds of lamellae: one type is represented by small triangular lamellae which aris from lateral scales, the second type is large and clearly visible and arises from ventral scales. None of the Heterolepidoderma species known so far has two types of lamellae. A. lamellophorus was previously known only from the Mediterranean Sea. The finding of two new gastrotrich species in the Baltic Sea shows that the knowledge of these small invertebrates in the area is still far from complete.

  13. Morphological abnormalities in gonads of the Baltic herring (Clupea harengus membras): Description of types and prevalence in the northern Baltic Sea.

    PubMed

    Rajasilta, Marjut; Elfving, Mikael; Hänninen, Jari; Laine, Päivi; Vuorinen, Ilppo; Paranko, Jorma

    2016-03-01

    Due to heavy anthropogenic influence and variation of the environmental conditions in the Baltic Sea, reproductive disorders are becoming a major environmental concern. We show here an increasing prevalence of gonadal malformations in the Baltic herring (Clupea harengus membras), a key species of the Baltic ecosystem and important in commercial fishery. During 1987-2014, the spawning herring population in the Archipelago Sea (AS) (North Baltic Sea, Finland) was monitored annually and analyzed for gross morphology of the gonads [total number (n) of analyzed fish = 38 284]. Four different types of malformations were repeatedly found and named as asymmetric, rudimentary, segmented, and branched gonads, but also hermaphroditic gonads and miscellaneous (unidentified) disorders were recorded. In 2013, additional samplings (n of fish analyzed = 541) showed similar malformations in herring from the Bothnian Sea. In some gonad types, histological examination revealed disintegration of seminiferous tubules and hyperplasia of the interstitial tissue. In 2014, the overall prevalence of malformations was still relatively low in the AS (frequency = 0-3.4 %; n = 750) and had apparently minimal effect on population recruitment. However, an increasing trend in the time-series (GLM; F = 32.65; p < 0.001) and a significantly higher prevalence in the Bothnian Sea (frequency = 0.7-5.0 %; n = 541; χ (2) = 6.24; p < 0.05) suggest that gonadal malformations may become a new threat for fish in the Baltic Sea. The observed gonad atrophies may be due to environmental endocrine disruption; however, also other explanations may exist and potential explanations are discussed.

  14. Measurements of Scattering Function of sea water in Southern Baltic

    NASA Astrophysics Data System (ADS)

    Freda, W.; Król1, T.; Martynov, O. V.; Shybanov, E. B.; Hapter, R.

    2007-05-01

    The Volume Scattering Functions (VSF) were measured in Southern Baltic area. The instrument used to this aim allow to measure in full range of angles and for four wavelengths. Obtained characteristics create the set of data which is need to solve the radiative transfer equation. Measured functions were compared with Petzold Average-Particle Phase Function. Spectral variations of measured scattering coefficients and backscattering coefficients are presented. Furthermore the instability of measured scattering ratios is discussed in this paper. Such instability have not been mentioned in the literature before.

  15. Modelling the variations and extremes of the sea level on the Finnish coast in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Kämäräinen, Matti; Kahma, Kimmo K.; Jokinen, Olli; Johansson, Milla M.; Särkkä, Jani

    2014-05-01

    A computationally highly effective model was developed to study the variations and extremes of the sea level in the Baltic Sea. The sea level model consists of two main components: 1) The spatial variability as well as the predominantly short-term variability was modelled by a simple barotropic dynamic model (Hansen), which was implemented by modelling the Baltic Sea as an enclosed basin. 2) The spatially uniform, predominantly long-term variability, was modelled by a water balance model of the Baltic Sea, which is based on the regression coefficients of the cross correlation function of the sea level and the zonal wind near the Danish Straits. Both sea level model components are forced by the air pressure gradient -based geostrophic wind, and component 1) in addition directly by the sea level air pressure distribution. For geostrophic wind calculations the 2-meter temperature field is used in addition, and for the transformation to the surface winds a location-based downscaling is applied. Atmospheric reanalysis ERA-40 (1961-2000) and the sea level observations from the Finnish tide gauge network were used to optimize the model system, both the atmospheric and the sea components. The model performance was then evaluated using independet ERA-Interim data from the years 1979-2013. The best correlation and RMS performance, measured between model results and observed sea levels, were 0.93 and 10 cm respectively. The optimised model setup was then used to study the performance of high resolution regional climate models from the ENSEMBLES project above the open Baltic Sea where almost no meteorological observations exist. The hindcast climate model runs forced by ERA-40 were used to evaluate the ability of the climate models to recreate the past low pressure situations in 1961-2000, and the A1B scenario forced runs were used for climate change studies in 1951-2100. Hindcast results with different climate models varied in the range 0.84-0.89 (correlation) and 13-17 cm

  16. Ecology, evolution, and management strategies of northern pike populations in the Baltic Sea.

    PubMed

    Larsson, Per; Tibblin, Petter; Koch-Schmidt, Per; Engstedt, Olof; Nilsson, Jonas; Nordahl, Oscar; Forsman, Anders

    2015-06-01

    Baltic Sea populations of the northern pike (Esox lucius) have declined since the 1990s, and they face additional challenges due to ongoing climate change. Pike in the Baltic Sea spawn either in coastal bays or in freshwater streams and wetlands. Pike recruited in freshwater have been found to make up about 50 % of coastal pike stocks and to show natal homing, thus limiting gene flow among closely located spawning sites. Due to natal homing, sub-populations appear to be locally adapted to their freshwater recruitment environments. Management actions should therefore not involve mixing of individuals originating from different sub-populations. We offer two suggestions complying with this advice: (i) productivity of extant freshwater spawning populations can be boosted by modifying wetlands such that they promote spawning and recruitment; and (ii) new sub-populations that spawn in brackish water can potentially be created by transferring fry and imprinting them on seemingly suitable spawning environments. PMID:26022327

  17. Eutrophication assessment of the Baltic Sea Protected Areas by available data and GIS technologies.

    PubMed

    Ranft, Susanne; Pesch, Roland; Schröder, Winfried; Boedeker, Dieter; Paulomäki, Hanna; Fagerli, Hilde

    2011-01-01

    Concerning increased degradation of marine ecosystems, there is a great political and institutional demand for an array of different tools to restore a good environmental status. Thereby, eutrophication is acknowledged as one of the major human induced stressors which has to be monitored and reduced. The present study concentrates on an assessment of the eutrophication status of the Baltic Sea Protected Areas by use of available data and GIS technologies. Two geodata layers were used for analysis: (1) a map on the eutrophication status of the Baltic Sea generated by the Helsinki Commission applying the HELCOM Eutrophication Assessment Tool (HEAT), and (2) modelled data on atmospheric nitrogen deposition made available by the European Monitoring and Evaluation Programme (EMEP). The results yielded comprehensive and conclusive data indicating that most of the BSPAs may be classified as being 'affected by eutrophication' and underlining the need to decrease the overall emissions of nutrients. PMID:21683967

  18. Governance of complex socio-environmental risks: the case of hazardous chemicals in the Baltic Sea.

    PubMed

    Karlsson, Mikael; Gilek, Michael; Udovyk, Oksana

    2011-03-01

    Complex socio-environmental risks challenge society. In response to scientific uncertainty and sociopolitical controversies, environmental governance, precaution, and the ecosystem approach to management are held forward as complements to governmental risk-based sector-restricted regulation. We analyze this development for hazardous substances in the Baltic Sea. Based on interviews and policy analysis, we study informal governance and, in particular, four central EU and international policies, and investigate how present governance relates to risks and objectives at hand. While showing emergence of broader governance approaches, we conclude that central objectives will not likely be met. Furthermore, we question the quest for broad environmental governance and emphasize the value of command and control regulation, if it implements precaution. These findings contribute to the theorizing on environmental (risk) governance. Finally, we provide some ideas that could help development and implementation of risk policies for hazardous chemicals in the Baltic Sea as well as other complex risks.

  19. Ecology, evolution, and management strategies of northern pike populations in the Baltic Sea.

    PubMed

    Larsson, Per; Tibblin, Petter; Koch-Schmidt, Per; Engstedt, Olof; Nilsson, Jonas; Nordahl, Oscar; Forsman, Anders

    2015-06-01

    Baltic Sea populations of the northern pike (Esox lucius) have declined since the 1990s, and they face additional challenges due to ongoing climate change. Pike in the Baltic Sea spawn either in coastal bays or in freshwater streams and wetlands. Pike recruited in freshwater have been found to make up about 50 % of coastal pike stocks and to show natal homing, thus limiting gene flow among closely located spawning sites. Due to natal homing, sub-populations appear to be locally adapted to their freshwater recruitment environments. Management actions should therefore not involve mixing of individuals originating from different sub-populations. We offer two suggestions complying with this advice: (i) productivity of extant freshwater spawning populations can be boosted by modifying wetlands such that they promote spawning and recruitment; and (ii) new sub-populations that spawn in brackish water can potentially be created by transferring fry and imprinting them on seemingly suitable spawning environments.

  20. The potential of current- and wind-driven transport for environmental management of the Baltic Sea.

    PubMed

    Soomere, Tarmo; Döös, Kristofer; Lehmann, Andreas; Meier, H E Markus; Murawski, Jens; Myrberg, Kai; Stanev, Emil

    2014-02-01

    The ever increasing impact of the marine industry and transport on vulnerable sea areas puts the marine environment under exceptional pressure and calls for inspired methods for mitigating the impact of the related risks. We describe a method for preventive reduction of remote environmental risks caused by the shipping and maritime industry that are transported by surface currents and wind impact to the coasts. This method is based on characterizing systematically the damaging potential of the offshore areas in terms of potential transport to vulnerable regions of an oil spill or other pollution that has occurred in a particular area. The resulting maps of probabilities of pollution to be transported to the nearshore and the time it takes for the pollution to reach the nearshore are used to design environmentally optimized fairways for the Gulf of Finland, Baltic Proper, and south-western Baltic Sea. PMID:24414808

  1. Eutrophication assessment of the Baltic Sea Protected Areas by available data and GIS technologies.

    PubMed

    Ranft, Susanne; Pesch, Roland; Schröder, Winfried; Boedeker, Dieter; Paulomäki, Hanna; Fagerli, Hilde

    2011-01-01

    Concerning increased degradation of marine ecosystems, there is a great political and institutional demand for an array of different tools to restore a good environmental status. Thereby, eutrophication is acknowledged as one of the major human induced stressors which has to be monitored and reduced. The present study concentrates on an assessment of the eutrophication status of the Baltic Sea Protected Areas by use of available data and GIS technologies. Two geodata layers were used for analysis: (1) a map on the eutrophication status of the Baltic Sea generated by the Helsinki Commission applying the HELCOM Eutrophication Assessment Tool (HEAT), and (2) modelled data on atmospheric nitrogen deposition made available by the European Monitoring and Evaluation Programme (EMEP). The results yielded comprehensive and conclusive data indicating that most of the BSPAs may be classified as being 'affected by eutrophication' and underlining the need to decrease the overall emissions of nutrients.

  2. Eutrophication, risk management and sustainability. The perceptions of different stakeholders in the northern Baltic Sea.

    PubMed

    Lundberg, Cecilia

    2013-01-15

    The environmental condition of the Baltic Sea is not only of concern for natural scientists. The awareness of the deteriorating state of the ecosystem has become an issue of interdisciplinary interest, and the amount of organizations with the marine environment and ecosystem health on the agenda is large. To present holistic and sustainable solutions and results of the actions taken, an active cooperation between all stakeholder groups and levels are needed. How different stakeholders in the northern Baltic Sea perceive the structures and assessments of the eutrophication were analyzed by semi-structured interviews with 17 stakeholders representing authorities, scientists, NGOs and national interest organizations. The focus was the view of the governance structures, risk assessment, management and communication. There was an overall consensus that eutrophication is a serious problem. Still variations in the opinions both within and between the stakeholder groups were seen. The scientists were most divergent from the rest.

  3. Framing environmental risks in the Baltic Sea: a news media analysis.

    PubMed

    Jönsson, Anna Maria

    2011-03-01

    Scientific complexity and uncertainty is a key challenge for environmental risk governance and to understand how risks are framed and communicated is of utmost importance. The Baltic Sea ecosystem is stressed and exposed to different risks like eutrophication, overfishing, and hazardous chemicals. Based on an analysis of the Swedish newspaper Dagens Nyheter, this study discusses media representations of these risks. The results show that the reporting on the Baltic Sea has been fairly stable since the beginning of the 1990s. Many articles acknowledge several risks, but eutrophication receives the most attention and is also considered the biggest threat. Authorities, experts, organizations, and politicians are the dominating actors, while citizens and industry representatives are more or less invisible. Eutrophication is not framed in terms of uncertainty concerning the risk and consequences, but rather in terms of main causes.

  4. No observed effect of ocean acidification on nitrogen biogeochemistry in a summer Baltic Sea plankton community

    NASA Astrophysics Data System (ADS)

    Paul, Allanah J.; Achterberg, Eric P.; Bach, Lennart T.; Boxhammer, Tim; Czerny, Jan; Haunost, Mathias; Schulz, Kai-Georg; Stuhr, Annegret; Riebesell, Ulf

    2016-07-01

    Nitrogen fixation by filamentous cyanobacteria supplies significant amounts of new nitrogen (N) to the Baltic Sea. This balances N loss processes such as denitrification and anammox, and forms an important N source supporting primary and secondary production in N-limited post-spring bloom plankton communities. Laboratory studies suggest that filamentous diazotrophic cyanobacteria growth and N2-fixation rates are sensitive to ocean acidification, with potential implications for new N supply to the Baltic Sea. In this study, our aim was to assess the effect of ocean acidification on diazotroph growth and activity as well as the contribution of diazotrophically fixed N to N supply in a natural plankton assemblage. We enclosed a natural plankton community in a summer season in the Baltic Sea near the entrance to the Gulf of Finland in six large-scale mesocosms (volume ˜ 55 m3) and manipulated fCO2 over a range relevant for projected ocean acidification by the end of this century (average treatment fCO2: 365-1231 µatm). The direct response of diazotroph growth and activity was followed in the mesocosms over a 47 day study period during N-limited growth in the summer plankton community. Diazotrophic filamentous cyanobacteria abundance throughout the study period and N2-fixation rates (determined only until day 21 due to subsequent use of contaminated commercial 15N-N2 gas stocks) remained low. Thus estimated new N inputs from diazotrophy were too low to relieve N limitation and stimulate a summer phytoplankton bloom. Instead, regeneration of organic N sources likely sustained growth in the plankton community. We could not detect significant CO2-related differences in neither inorganic nor organic N pool sizes, or particulate matter N : P stoichiometry. Additionally, no significant effect of elevated CO2 on diazotroph activity was observed. Therefore, ocean acidification had no observable impact on N cycling or biogeochemistry in this N-limited, post-spring bloom

  5. Shelf-to-basin iron shuttling enhances vivianite formation in deep Baltic Sea sediments

    NASA Astrophysics Data System (ADS)

    Reed, Daniel C.; Gustafsson, Bo G.; Slomp, Caroline P.

    2016-01-01

    Coastal hypoxia is a growing and persistent problem largely attributable to enhanced terrestrial nutrient (i.e., nitrogen and phosphorus) loading. Recent studies suggest phosphorus removal through burial of iron (II) phosphates, putatively vivianite, plays an important role in nutrient cycling in the Baltic Sea - the world's largest anthropogenic dead zone - yet the dynamics of iron (II) phosphate formation are poorly constrained. To address this, a reactive-transport model was used to reconstruct the diagenetic and depositional history of sediments in the Fårö basin, a deep anoxic and sulphidic region of the Baltic Sea where iron (II) phosphates have been observed. Simulations demonstrate that transport of iron from shelf sediments to deep basins enhances vivianite formation while sulphide concentrations are low, but that pyrite forms preferentially over vivianite when sulphate reduction intensifies due to elevated organic loading. Episodic reoxygenation events, associated with major inflows of oxic waters, encourage the retention of iron oxyhydroxides and iron-bound phosphorus in sediments, increasing vivianite precipitation as a result. Results suggest that artificial reoxygenation of the Baltic Sea bottom waters could sequester up to 3% of the annual external phosphorus loads as iron (II) phosphates, but this is negligible when compared to potential internal phosphorus loads due to dissolution of iron oxyhydroxides when low oxygen conditions prevail. Thus, enhancing vivianite formation through artificial reoxygenation of deep waters is not a viable engineering solution to eutrophication in the Baltic Sea. Finally, simulations suggest that regions with limited sulphate reduction and hypoxic intervals, such as eutrophic estuaries, could act as important phosphorus sinks by sequestering vivianite. This could potentially alleviate eutrophication in shelf and slope environments.

  6. Sensitivity of oxygen dynamics in the water column of the Baltic Sea to external forcing

    NASA Astrophysics Data System (ADS)

    Miladinova, S.; Stips, A.

    2010-04-01

    A 1-D biogeochemical/physical model of marine systems has been applied to study the oxygen cycle in four stations of different sub-basins of the Baltic Sea, namely, in the Gotland Deep, Bornholm, Arkona and Fladen. The model consists of the biogeochemical model of Neumann et al. (2002) coupled with the 1-D General Ocean Turbulence Model (GOTM). The model has been forced with meteorological data from the ECMWF reanalysis project for the period 1998-2003, producing a six year hindcast which is validated with datasets from the Baltic Environmental Database (BED) for the same period. The vertical profiles of temperature and salinity are relaxed towards both profiles provided by 3-D simulations of General Estuarine Transport Model (GETM) and observed profiles from BED. Modifications in the parameterisation of the air-sea oxygen fluxes have led to a significant improvement of the model results in the surface and intermediate water layers. The largest mismatch with observations is found in simulating the oxygen dynamics in the Baltic Sea bottom waters. The model results demonstrate the good capability of the model to predict the time-evolution of the physical and biogeochemical variables at all different stations. Comparative analysis of the modelled oxygen concentrations with respect to observation data is performed to distinguish the relative importance of several factors on the seasonal, interannual and long-term variations of oxygen. It is found that natural physical factors, like the magnitude of the vertical turbulent mixing, wind speed and the variation of temperature and salinity fields are the major factors controlling the oxygen dynamics in the Baltic Sea. The influence of limiting nutrients is less pronounced, at least under the nutrient flux parameterisation assumed in the model.

  7. Precision and accuracy of spectrophotometric pH measurements at environmental conditions in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Hammer, Karoline; Schneider, Bernd; Kuliński, Karol; Schulz-Bull, Detlef E.

    2014-06-01

    The increasing uptake of anthropogenic CO2 by the oceans has raised an interest in precise and accurate pH measurement in order to assess the impact on the marine CO2-system. Spectrophotometric pH measurements were refined during the last decade yielding a precision and accuracy that cannot be achieved with the conventional potentiometric method. However, until now the method was only tested in oceanic systems with a relative stable and high salinity and a small pH range. This paper describes the first application of such a pH measurement system at conditions in the Baltic Sea which is characterized by a wide salinity and pH range. The performance of the spectrophotometric system at pH values as low as 7.0 (“total” scale) and salinities between 0 and 35 was examined using TRIS-buffer solutions, certified reference materials, and tests of consistency with measurements of other parameters of the marine CO2 system. Using m-cresol purple as indicator dye and a spectrophotometric measurement system designed at Scripps Institution of Oceanography (B. Carter, A. Dickson), a precision better than ±0.001 and an accuracy between ±0.01 and ±0.02 was achieved within the observed pH and salinity ranges in the Baltic Sea. The influence of the indicator dye on the pH of the sample was determined theoretically and is presented as a pH correction term for the different alkalinity regimes in the Baltic Sea. Because of the encouraging tests, the ease of operation and the fact that the measurements refer to the internationally accepted “total” pH scale, it is recommended to use the spectrophotometric method also for pH monitoring and trend detection in the Baltic Sea.

  8. No observed effect of ocean acidification on nitrogen biogeochemistry in a summer Baltic Sea plankton community

    NASA Astrophysics Data System (ADS)

    Paul, A. J.; Achterberg, E. P.; Bach, L. T.; Boxhammer, T.; Czerny, J.; Haunost, M.; Schulz, K.-G.; Stuhr, A.; Riebesell, U.

    2015-10-01

    Nitrogen fixation by filamentous cyanobacteria supplies significant amounts of new nitrogen (N) to the Baltic Sea. This balances N loss processes such as denitrification and anammox and forms an important N source supporting primary and secondary production in N-limited post-spring bloom plankton communities. Laboratory studies suggest that filamentous diazotrophic cyanobacteria growth and N2-fixation rates are sensitive to ocean acidification with potential implications for new N supply to the Baltic Sea. In this study, our aim was to assess the effect of ocean acidification on diazotroph growth and activity as well as the contribution of diazotrophically-fixed N to N supply in a natural plankton assemblage. We enclosed a natural plankton community in a summer season in the Baltic Sea near the entrance to the Gulf of Finland in six large-scale mesocosms (volume ~ 55 m3) and manipulated fCO2 over a range relevant for projected ocean acidification by the end of this century (average treatment fCO2: 365-1231 μatm). The direct response of diazotroph growth and activity was followed in the mesocosms over a 47 day study period during N-limited growth in the summer plankton community. Diazotrophic filamentous cyanobacteria abundance throughout the study period and N2-fixation rates (determined only until day 21 due to subsequent use of contaminated commercial 15N-N2 gas stocks) remained low. Thus estimated new N inputs from diazotrophy were too low to relieve N limitation and stimulate a summer phytoplankton bloom. Instead regeneration of organic N sources likely sustained growth in the plankton community. We could not detect significant CO2-related differences in inorganic or organic N pools sizes, or particulate matter N : P stoichiometry. Additionally, no significant effect of elevated CO2 on diazotroph activity was observed. Therefore, ocean acidification had no observable impact on N cycling or biogeochemistry in this N-limited, post-spring bloom plankton

  9. Photochemical mineralization of dissolved organic nitrogen to ammonium in the Baltic sea.

    PubMed

    Vahätalo, Anssi V; Zepp, Richard G

    2005-09-15

    Solar-radiation-induced photochemistry can be considered as a new source of nutrients when photochemical reactions release bioavailable nitrogen from biologically nonreactive dissolved organic nitrogen (DON). Pretreatments of Baltic Sea waters in the dark indicated that >72% of DON was recalcitrant to biological mineralization. When this DON (16-21.5 microM) was exposed to simulated solar radiation, the concentration of NH4+ increased 0.5-2.5 microM more in irradiated waters than in the dark controls. The photochemical production of NH4+ and the dose of absorbed photons were used to calculate the apparent quantum yield spectrum for photoammonification [mol NH4+ (mol photons)(-1) nm(-1)] at wavelengths (lambda) of 290-700 nm (phiNH4,lambda). The modeled mean rates of photoammonification based on phiNH4,lambda were 143 and 53 micromol NH4+ m(-2) d(-1) at the surface and in the whole water column, respectively, of Baltic Sea stations during summer. The results of this study indicate thatthe rate of photoammonification approximately equals and periodically exceeds the rate of atmospheric deposition of reactive inorganic nitrogen to the northern Baltic Sea. Forthese stratified surface waters beyond riverine input of labile nitrogen, photoammonification can periodically be the largest source of new bioavailable nitrogen. PMID:16201620

  10. Nutrient abatement potential and abatement costs of waste water treatment plants in the Baltic Sea region.

    PubMed

    Hautakangas, Sami; Ollikainen, Markku; Aarnos, Kari; Rantanen, Pirjo

    2014-04-01

    We assess the physical potential to reduce nutrient loads from waste water treatment plants in the Baltic Sea region and determine the costs of abating nutrients based on the estimated potential. We take a sample of waste water treatment plants of different size classes and generalize its properties to the whole population of waste water treatment plants. Based on a detailed investment and operational cost data on actual plants, we develop the total and marginal abatement cost functions for both nutrients. To our knowledge, our study is the first of its kind; there is no other study on this issue which would take advantage of detailed data on waste water treatment plants at this extent. We demonstrate that the reduction potential of nutrients is huge in waste water treatment plants. Increasing the abatement in waste water treatment plants can result in 70 % of the Baltic Sea Action Plan nitrogen reduction target and 80 % of the Baltic Sea Action Plan phosphorus reduction target. Another good finding is that the costs of reducing both nutrients are much lower than previously thought. The large reduction of nitrogen would cost 670 million euros and of phosphorus 150 million euros. We show that especially for phosphorus the abatement costs in agriculture would be much higher than in waste water treatment plants.

  11. Reconstructing ecosystem functions of the active microbial community of the Baltic Sea oxygen depleted sediments

    PubMed Central

    Franzetti, Andrea; Lundin, Daniel; Sjöling, Sara

    2016-01-01

    Baltic Sea deep water and sediments hold one of the largest anthropogenically induced hypoxic areas in the world. High nutrient input and low water exchange result in eutrophication and oxygen depletion below the halocline. As a consequence at Landsort Deep, the deepest point of the Baltic Sea, anoxia in the sediments has been a persistent condition over the past decades. Given that microbial communities are drivers of essential ecosystem functions we investigated the microbial community metabolisms and functions of oxygen depleted Landsort Deep sediments by metatranscriptomics. Results show substantial expression of genes involved in protein metabolism demonstrating that the Landsort Deep sediment microbial community is active. Identified expressed gene suites of metabolic pathways with importance for carbon transformation including fermentation, dissimilatory sulphate reduction and methanogenesis were identified. The presence of transcripts for these metabolic processes suggests a potential for heterotrophic-autotrophic community synergism and indicates active mineralisation of the organic matter deposited at the sediment as a consequence of the eutrophication process. Furthermore, cyanobacteria, probably deposited from the water column, are transcriptionally active in the anoxic sediment at this depth. Results also reveal high abundance of transcripts encoding integron integrases. These results provide insight into the activity of the microbial community of the anoxic sediment at the deepest point of the Baltic Sea and its possible role in ecosystem functioning. PMID:26823996

  12. 137Cs and 90Sr behavioural regularities in the southeastern part of the Baltic Sea.

    PubMed

    Styro, D; Bumeliene, Z; Lukinskiene, M; Morkuniene, R

    2001-01-01

    Variations in 137Cs concentrations were investigated over the period 1986-1997 in the southeastern part of the Baltic Sea, following the Chernobyl power plant accident. The rate of "self-cleaning" was demonstrated to be very slow, the average concentration of 137Cs in 1996 being almost the same as that measured directly after the accident, in 1986. Measurements of both 137Cs and 90Sr concentrations generally revealed homogeneous distributions in this region of the Baltic Sea, though patchy distributions did develop under some hydrometeorological conditions. Specifically, the 137Cs concentration distribution became heterogeneous with values varying in the range 60-92 Bq/m3 under south-southwesterly wind conditions whilst the 90Sr concentration distribution developed similar characteristics with values ranging from 15 to 64 Bq/m3 under east-southeasterly wind conditions. In addition, in coastal waters, over extensive periods of north-northwesterly winds in 1995, 137Cs concentrations increased to values 1.5-2 times the overall average concentration, which was registered in 1986 and 1996. These data therefore reveal a continuing significant pollution of the waters of the Baltic Sea resulting from the Chernobyl power plant accident, a pollution compounded by the slow rate of radionuclide self-cleaning and significant probability of sudden regional concentration increase.

  13. nirS-containing denitrifier communities in the water column and sediment of the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Falk, S.; Hannig, M.; Gliesche, C.; Wardenga, R.; Köster, M.; Jürgens, K.; Braker, G.

    2007-05-01

    The aim of this study was to compare structural differences in the nirS-type denitrifying microbial communities along the environmental gradients observed in the water column and coastal sediments of the Baltic Sea. To link community structure and environmental gradients, denitrifier communities were analyzed by terminal restriction fragment length polymorphism (T-RFLP) based on nirS as a functional marker gene for denitrification. nirS-type denitrifier community composition was further evaluated by phylogenetic analysis of nirS sequences from clone libraries. T-RFLP analysis indicated some overlap but also major differences between communities from the water column and the sediment. Shifts in community composition along the biogeochemical gradients were observed only in the water column while denitrifier communities were rather uniform within the upper 30 mm of the sediment. Specific terminal restriction fragments (T-RFs) indicative of the sulfidic zone suggest the presence of nitrate-reducing and sulfide-oxidizing microorganisms that were previously shown to be important at the suboxic-sulfidic interface in the water column of the Baltic Sea. Phylogenetic analysis of nirS genes from the Baltic Sea and of sequences from marine habitats all over the world indicated distinct denitrifier communities that grouped mostly according to their habitats. We suggest that these subgroups of denitrifiers had developed after selection through several factors, i.e. their habitats (water column or sediment), impact by prevalent environmental conditions and isolation by large geographic distances between habitats.

  14. Distribution and sources of organic matter in sediments of the south-eastern Baltic Sea

    NASA Astrophysics Data System (ADS)

    Remeikaitė-Nikienė, Nijolė; Lujanienė, Galina; Malejevas, Vitalijus; Barisevičiūtė, Rūta; Žilius, Mindaugas; Garnaga-Budrė, Galina; Stankevičius, Algirdas

    2016-05-01

    Temporal and spatial distribution of sedimentary organic matter (SOM) as well as its sources in the south-eastern Baltic Sea were investigated. Organic matter was characterized by the organic carbon content, δ13C and δ15N signatures and C/N ratios. The sampling was performed in the coastal, offshore areas and in the Curonian Lagoon in the period from May 2012 to September 2014. The average elemental (C/N ~ 6.4) and isotopic composition (δ13C from - 29.6‰ to - 24.9‰) of SOM suggested that during most of the year it was composed of both freshwater and marine phytoplanktonic material. Elevated δ15N values (average ranging from 5.6‰ to 6.7‰) were detected in SOM from the Curonian Lagoon. This most likely reflected the increased isotopic signal of the Nemunas River (δ15N ~ 8‰) derived from the anthropogenic input in the basin area. At the Baltic Sea offshore sites, SOM had lower δ15N values (δ15N ~ 3.5‰ on average), indicating phytoplankton blooms. A two-end member mixing model based on the carbon stable isotopic composition showed that a large proportion (~ 90%) of SOM in the northern part of the Curonian Lagoon was of the freshwater origin. The allochthonous organic matter accounted for about 47% of SOM in the studied Baltic Sea area with the highest contribution (about 75%) within the Curonian Lagoon plume zone in the coastal waters.

  15. Microbial metagenomics in the Baltic Sea: Recent advancements and prospects for environmental monitoring.

    PubMed

    Ininbergs, Karolina; Bergman, Birgitta; Larsson, John; Ekman, Martin

    2015-06-01

    Metagenomics refers to the analysis of DNA from a whole community. Metagenomic sequencing of environmental DNA has greatly improved our knowledge of the identity and function of microorganisms in aquatic, terrestrial, and human biomes. Although open oceans have been the primary focus of studies on aquatic microbes, coastal and brackish ecosystems are now being surveyed. Here, we review so far published studies on microbes in the Baltic Sea, one of the world's largest brackish water bodies, using high throughput sequencing of environmental DNA and RNA. Collectively the data illustrate that Baltic Sea microbes are unique and highly diverse, and well adapted to this brackish-water ecosystem, findings that represent a novel base-line knowledge necessary for monitoring purposes and a sustainable management. More specifically, the data relate to environmental drivers for microbial community composition and function, assessments of the microbial biodiversity, adaptations and role of microbes in the nitrogen cycle, and microbial genome assembly from metagenomic sequences. With these discoveries as background, prospects of using metagenomics for Baltic Sea environmental monitoring are discussed.

  16. Reconstructing ecosystem functions of the active microbial community of the Baltic Sea oxygen depleted sediments.

    PubMed

    Thureborn, Petter; Franzetti, Andrea; Lundin, Daniel; Sjöling, Sara

    2016-01-01

    Baltic Sea deep water and sediments hold one of the largest anthropogenically induced hypoxic areas in the world. High nutrient input and low water exchange result in eutrophication and oxygen depletion below the halocline. As a consequence at Landsort Deep, the deepest point of the Baltic Sea, anoxia in the sediments has been a persistent condition over the past decades. Given that microbial communities are drivers of essential ecosystem functions we investigated the microbial community metabolisms and functions of oxygen depleted Landsort Deep sediments by metatranscriptomics. Results show substantial expression of genes involved in protein metabolism demonstrating that the Landsort Deep sediment microbial community is active. Identified expressed gene suites of metabolic pathways with importance for carbon transformation including fermentation, dissimilatory sulphate reduction and methanogenesis were identified. The presence of transcripts for these metabolic processes suggests a potential for heterotrophic-autotrophic community synergism and indicates active mineralisation of the organic matter deposited at the sediment as a consequence of the eutrophication process. Furthermore, cyanobacteria, probably deposited from the water column, are transcriptionally active in the anoxic sediment at this depth. Results also reveal high abundance of transcripts encoding integron integrases. These results provide insight into the activity of the microbial community of the anoxic sediment at the deepest point of the Baltic Sea and its possible role in ecosystem functioning. PMID:26823996

  17. Simulated distributions of Baltic Sea-ice in warming climate and consequences for the winter habitat of the Baltic ringed seal.

    PubMed

    Meier, H E Markus; Döscher, Ralf; Halkka, Antti

    2004-06-01

    Sea-ice in the Baltic Sea in present and future climates is investigated. The Rossby Centre Regional Atmosphere-Ocean model was used to perform a set of 30-year-long time slice experiments. For each of the two driving global models HadAM3H and ECHAM4/OPYC3, one control run (1961-1990) and two scenario runs (2071-2100) based upon the SRES A2 and B2 emission scenarios were conducted. The future sea-ice volume in the Baltic Sea is reduced by 83% on average. The Bothnian Sea, large areas of the Gulf of Finland and Gulf of Riga, and the outer parts of the southwestern archipelago of Finland will become ice-free in the mean. The presented scenarios are used to study the impact of climate change on the Baltic ringed seal (Phoca hispida botnica). Climate change seems to be a major threat to all southern populations. The only fairly good winter sea-ice habitat is found to be confined to the Bay of Bothnia.

  18. Towards an improved understanding of Baltic Sea hypoxia during the Holocene: preliminary results from IODP Expedition 347

    NASA Astrophysics Data System (ADS)

    Slomp, Caroline; Dijkstra, Nikki; Egger, Matthias; Gustafsson, Bo; Ash, Jeanine; Bauersachs, Thorsten; Hardisty, Dalton; Martin, Ellen; Riedinger, Natascha; Andren, Thomas; Barker Jorgensen, Bo

    2015-04-01

    The Baltic Sea is a restricted brackish-marine basin that is highly sensitive to changes in climate and anthropogenic activity. Due to its salinity stratification, the Baltic Sea is particularly vulnerable to hypoxia (oxygen concentrations < 2 ml/L). Besides the modern, human-induced period of hypoxia (since A.D. 1960), there is evidence for two earlier major intervals of hypoxia since the transition of the Baltic Sea from the Ancylus freshwater phase to the Littorina brackish-marine phase. These are the Holocene Thermal Maximum (HTM), ca. 8-4 ka, and the Medieval Climate Anomaly (MCA), ca. 1-0.7 ka (Zillen et al., 2008; Jilbert and Slomp, 2013). While changes in salinity, temperature and the input and recycling of nutrients all may contribute to the development of hypoxia in the Baltic Sea, their relative importance in driving the hypoxia during the MCA and HTM is still incompletely understood. Here, we use porewater and sediment geochemical data obtained during the IODP Expedition 347: Baltic Sea Paleoenvironment (September 13 - November 1, 2013) to obtain further insight into the role of changes in salinity and phosphorus recycling during the HTM. We focus on three sites along the modern salinity gradient in the Baltic Sea, Sites M0059, M0063 and M0065. Our results indicate that bottom water salinity in the Baltic Proper was higher during the HTM than at present, confirming previous studies that increased salinity stratification may have contributed to the development of hypoxia during the HTM. We also discuss evidence for temporal changes and spatial differences in primary productivity and phosphorus burial and recycling in the Baltic Sea and their potential role in contributing to the development of hypoxia during the HTM and MCA. References: Jilbert, T., and Slomp, C.P. (2013). Rapid high-amplitude variability in Baltic Sea hypoxia during the Holocene. Geology 41, 1183-1186. doi: 10.1130/g34804.1. Zillén, L., Conley, D.J., Andrén, T., Andrén, E., and Bj

  19. Evaluation of the operational SAR based Baltic sea ice concentration products

    NASA Astrophysics Data System (ADS)

    Karvonen, Juha

    Sea ice concentration is an important ice parameter both for weather and climate modeling and sea ice navigation. We have developed an fully automated algorithm for sea ice concentration retrieval using dual-polarized ScanSAR wide mode RADARSAT-2 data. RADARSAT-2 is a C-band SAR instrument enabling dual-polarized acquisition in ScanSAR mode. The swath width for the RADARSAT-2 ScanSAR mode is about 500 km, making it very suitable for operational sea ice monitoring. The polarization combination used in our concentration estimation is HH/HV. The SAR data is first preprocessed, the preprocessing consists of geo-rectification to Mercator projection, incidence angle correction fro both the polarization channels. and SAR mosaicking. After preprocessing a segmentation is performed for the SAR mosaics, and some single-channel and dual-channel features are computed for each SAR segment. Finally the SAR concentration is estimated based on these segment-wise features. The algorithm is similar as introduced in Karvonen 2014. The ice concentration is computed daily using a daily RADARSAT-2 SAR mosaic as its input, and it thus gives the concentration estimated at each Baltic Sea location based on the most recent SAR data at the location. The algorithm has been run in an operational test mode since January 2014. We present evaluation of the SAR-based concentration estimates for the Baltic ice season 2014 by comparing the SAR results with gridded the Finnish Ice Service ice charts and ice concentration estimates from a radiometer algorithm (AMSR-2 Bootstrap algorithm results). References: J. Karvonen, Baltic Sea Ice Concentration Estimation Based on C-Band Dual-Polarized SAR Data, IEEE Transactions on Geoscience and Remote Sensing, in press, DOI: 10.1109/TGRS.2013.2290331, 2014.

  20. Model simulations of dense bottom currents in the Western Baltic Sea

    NASA Astrophysics Data System (ADS)

    Burchard, Hans; Janssen, Frank; Bolding, Karsten; Umlauf, Lars; Rennau, Hannes

    2009-01-01

    Only recently, medium intensity inflow events into the Baltic Sea have gained more awareness because of their potential to ventilate intermediate layers in the Southern Baltic Sea basins. With the present high-resolution model study of the Western Baltic Sea a first attempt is made to obtain model based realistic estimates of turbulent mixing in this area where dense bottom currents resulting from medium intensity inflow events are weakened by turbulent entrainment. The numerical model simulation which is carried out using the General Estuarine Transport Model (GETM) during nine months in 2003 and 2004 is first validated by means of three automatic stations at the Drogden and Darss Sills and in the Arkona Sea. In order to obtain good agreement between observations and model results, the 0.5×0.5 nautical mile bathymetry had to be adjusted in order to account for the fact that even at that scale many relevant topographic features are not resolved. Current velocity, salinity and turbulence observations during a medium intensity inflow event through the Øresund are then compared to the model results. Given the general problems of point to point comparisons between observations and model simulations, the agreement is fairly good with the characteristic features of the inflow event well represented by the model simulations. Two different bulk measures for mixing activity are then introduced, the vertically integrated decay of salinity variance, which is equal to the production of micro-scale salinity variance, and the vertically integrated turbulent salt flux, which is related to an increase of potential energy due to vertical mixing of stably stratified flow. Both measures give qualitatively similar results and identify the Drogden and Darss Sills as well as the Bornholm Channel as mixing hot spots. Further regions of strong mixing are the dense bottom current pathways from these sills into the Arkona Sea, areas around Kriegers Flak (a shoal in the western Arkona Sea

  1. Vertical thermo-haline structure of the Baltic Sea cold intermediate layer

    NASA Astrophysics Data System (ADS)

    Stepanova, Natalya

    2016-04-01

    Main characteristic features of vertical thermo-haline structure of the cold intermediate layer (CIL) of the Baltic Sea are identified on the base of data of vertical CTD soundings in the Baltic Proper in 2004-2013. Permanently existing components (i.e., the components which are observed during the entire period of the presence of the CIL in the vertical thermo-haline structure of the sea) are: (i) quasi-homosaline sublayer, with water salinity typical for that in the upper mixed layer in winter period, and water temperature irregularly changing with depth; (ii) the underlying sublayer with increasing salinity and low temperature (the gradient sublayer); and (iii) the core of CIL (the minimum temperature), which is located close to the interface between these sublayers. It is argued that the homosaline sublayer is formed by local mechanisms - vertical wind-wave and convective mixing and advection from nearby shelves and neighbouring regions. Advection is supported by (i) long-lasting winds and (ii) horizontal convection due to differential warming / cooling of shallower regions. The gradient sublayer is formed by waters with T,S - parameters typical for that of the upper mixed layer of south-western sea basins (Barnholm and Arcons basins) at the beginning of spring warming-up period (March). It is suggested that the up-estuary propagation of these waters (with salinity about 7.5-8.5 psu) above the pycnocline is driven by the estuarine salinity gradient. This branch of circulation of intermediate waters is overlooked in classical estuarine circulation model of the Baltic Sea, however it is important for sea-scale transport of upper-layer contaminants, microplastics, organic matter etc. towards intermediate and deep sea layers. The investigations are supported by Russian Science Foundation via grant number 15-17-10020.

  2. Sea level rise of semi-enclosed basins: deviation of Adriatic and Baltic sea level from the mean global value.

    NASA Astrophysics Data System (ADS)

    Scarascia, Luca; Lionello, Piero

    2015-04-01

    Future sea level rise (SL), which represents today one of the major threats that are caused by climate change, will not be uniform. Regional differences are crucial for 40% of the world population, which is located in the coastal zone. To explore the mechanisms linking regional SL to climate variables is very important in order to provide reliable future projections. This study focuses on two semi-enclosed basins, the Adriatic and Baltic Sea and investigates the deviation of their SL from the mean global value. In fact, past deviations of the SL of these two basins from the global value have been observed and can be attributed to large scale factors (such as teleconnections) and regional factors, such as the inverse barometric effect, the wind stress, the thermosteric and halosteric effects. The final goal of this work is to assess to which extent the Adriatic and Baltic SL will depart from the mean global value in the next decades and at the end of 21st century. This is achieved by analyzing deviations of the mean SL of the Baltic and Adriatic Sea from the global mean SL during the 20th century and investigating which factors can explain such deviations. A multivariate linear regression model is built and used to describe the link between three large scale climate variables which are used as predictors (mean sea level pressure, surface air temperature and precipitation), and the regional SL deviation (the predictand), computed as the difference between the regional and the global SL. At monthly scale this linear regression model provides a good reconstruction of the past variability in the cold season during which it explains 60%-70% of the variance. Summer reconstruction is substantially less successful and it represents presently the main limit of the model skill. This linear regression model, forced by predictors extracted from CMIP5 multi-model simulations, is used to provide projections of SL in the Adriatic and Baltic Sea. On the basis of the projections

  3. Decadal-Scale Changes of Dinoflagellates and Diatoms in the Anomalous Baltic Sea Spring Bloom

    PubMed Central

    Klais, Riina; Tamminen, Timo; Kremp, Anke; Spilling, Kristian; Olli, Kalle

    2011-01-01

    The algal spring bloom in the Baltic Sea represents an anomaly from the winter-spring bloom patterns worldwide in terms of frequent and recurring dominance of dinoflagellates over diatoms. Analysis of approximately 3500 spring bloom samples from the Baltic Sea monitoring programs revealed (i) that within the major basins the proportion of dinoflagellates varied from 0.1 (Kattegat) to >0.8 (central Baltic Proper), and (ii) substantial shifts (e.g. from 0.2 to 0.6 in the Gulf of Finland) in the dinoflagellate proportion over four decades. During a recent decade (1995–2004) the proportion of dinoflagellates increased relative to diatoms mostly in the northernmost basins (Gulf of Bothnia, from 0.1 to 0.4) and in the Gulf of Finland, (0.4 to 0.6) which are typically ice-covered areas. We hypothesize that in coastal areas a specific sequence of seasonal events, involving wintertime mixing and resuspension of benthic cysts, followed by proliferation in stratified thin layers under melting ice, favors successful seeding and accumulation of dense dinoflagellate populations over diatoms. This head-start of dinoflagellates by the onset of the spring bloom is decisive for successful competition with the faster growing diatoms. Massive cyst formation and spreading of cyst beds fuel the expanding and ever larger dinoflagellate blooms in the relatively shallow coastal waters. Shifts in the dominant spring bloom algal groups can have significant effects on major elemental fluxes and functioning of the Baltic Sea ecosystem, but also in the vast shelves and estuaries at high latitudes, where ice-associated cold-water dinoflagellates successfully compete with diatoms. PMID:21747911

  4. Essential and Toxic Elements in Blood Samples of Harbor Seals (Phoca vitulina) from the Islands Helgoland (North Sea) and Anholt (Baltic Sea): A Comparison Study with Urbanized Areas.

    PubMed

    Kakuschke, Antje; Griesel, Simone

    2016-01-01

    The harbor seals (Phoca vitulina) from Helgoland (North Sea) and Anholt (Kattegat, Baltic Sea) are top predators within the marine food web and an indicator species of the environmental contamination. Furthermore, they are a main tourist attraction. Despite these important roles, little is known about the health and pollutant contamination of these seals. The objective of this study was therefore to investigate 18 essential and nonessential/toxic elements (Al, As, Be, Ca, Cr, Cu, Fe, K, Mn, Mo, Ni, P, Pb, Rb, S, Se, Sr, and Zn) in blood samples using inductively coupled plasma mass spectrometry and total X-ray-fluorescence spectrometry. Blood concentrations of mineral nutrients, such as Ca, K, P, and S, were within the reference ranges described for harbor seals. Likewise, for the trace elements, As, Be, Rb, Se, and Sr, no significant differences were observed compared with previous studies. Interestingly, blood concentrations of nine nonessential as well as essential trace metals (Al, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Zn) measured significantly lower in the offshore living seals from Helgoland and Anholt compared with results obtained from animals living close to urbanized areas, such as the Wadden Sea and Elbe estuary. This suggests that industrial emissions, sewage deposition, shipping traffic and dredging tasks might be the cause of increased metal concentrations of inshore harbor seals.

  5. Large spatial variations in coastal 14C reservoir age - a case study from the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Lougheed, B. C.; Filipsson, H. L.; Snowball, I.

    2013-02-01

    Coastal locations are highly influenced by input from freshwater river runoff, including sources of terrestrial carbon, which can be expected to modify the 14C reservoir age, or R(t), associated with marine water. In this Baltic Sea case study, pre-bomb museum collection mollusc shells of known calendar age, from 30 locations across a strategic salinity transect of the Baltic Sea, were analysed for 14C, δ13C and δ18O. R(t) was calculated for all 30 locations. Seven locations, of which six are within close proximity of the coast, were found to have relatively higher R(t) values, indicative of hard-water effects. δ13Caragonite values were found to be indicative of hard-water influence only for certain locations, suggesting the possibility of different sources of old carbon in different locations. Whenever possible, the Macoma genus of mollusc was selected from the museum collections, in order to exclude species specific reservoir age effects as much as possible. When the Macoma samples are exclusively considered, and samples from hard-water locations excluded, a statistically significant correlation between Macoma R(t) and average salinity is found, indicating a two end-member linear mixing model between 14Cmarine and 14Crunoff. A map of Baltic Sea Macoma aragonite R(t) for the late 19th and early 20th centuries is produced. Such a map can provide an estimate for contemporary Baltic Sea Macoma R(t), although one must exercise caution when applying such estimates back in time or to 14C dates obtained from different sample material. A statistically significant correlation is also found between δ18Oaragonite and Macoma R(t), suggesting that δ18Oaragonite can be used to estimate Macoma palaeo-R(t). The results of this Baltic Sea case study, which show that R(t) is affected by hydrographic conditions and local carbon inputs, have important consequences for other coastal and estuarine locations, where R(t) is also likely to significantly vary on spatial and temporal

  6. Reprint of: The ecophysiology of Sprattus sprattus in the Baltic and North Seas

    NASA Astrophysics Data System (ADS)

    Peck, Myron A.; Baumann, Hannes; Bernreuther, Matthias; Clemmesen, Catriona; Herrmann, Jens-Peter; Haslob, Holger; Huwer, Bastian; Kanstinger, Philipp; Köster, Fritz W.; Petereit, Christoph; Temming, Axel; Voss, Rudi

    2012-12-01

    The European sprat (Sprattus sprattus) was a main target species of the German GLOBEC program that investigated the trophodynamic structure and function of the Baltic and North Seas under the influence of physical forcing. This review summarizes literature on the ecophysiology of sprat with an emphasis on describing how environmental factors influence the life-history strategy of this small pelagic fish. Ontogenetic changes in feeding and growth, and the impacts of abiotic and biotic factors on vital rates are discussed with particular emphasis on the role of temperature as a constraint to life-history scheduling of this species in the Baltic Sea. A combination of field and laboratory data suggests that optimal thermal windows for growth and survival change during early life and are wider for eggs (5-17 °C) than in young (8- to 12-mm) early feeding larvae (5-12 °C). As larvae become able to successfully capture larger prey, thermal windows expand to include warmer waters. For example, 12- to 16-mm larvae can grow well at 16 °C and larger, transitional-larvae and early juveniles display the highest rates of feeding and growth at ∼18-22 °C. Gaps in knowledge are identified including the need for additional laboratory studies on the physiology and behavior of larvae (studies that will be particularly critical for biophysical modeling activities) and research addressing the role of overwinter survival as a factor shaping phenology and setting limits on the productivity of this species in areas located at the northern limits of its latitudinal range (such as the Baltic Sea). Based on stage- and temperature-specific mortality and growth potential of early life stages, our analysis suggests that young-of-the year sprat would benefit from inhabiting warmer, near-shore environments rather than the deeper-water spawning grounds such as the Bornholm Basin (central Baltic Sea). Utilization of warmer, nearshore waters (or a general increase in Baltic Sea temperatures) is

  7. The ecophysiology of Sprattus sprattus in the Baltic and North Seas

    NASA Astrophysics Data System (ADS)

    Peck, Myron A.; Baumann, Hannes; Bernreuther, Matthias; Clemmesen, Catriona; Herrmann, Jens-Peter; Haslob, Holger; Huwer, Bastian; Kanstinger, Philipp; Köster, Fritz W.; Petereit, Christoph; Temming, Axel; Voss, Rudi

    2012-09-01

    The European sprat (Sprattus sprattus) was a main target species of the German GLOBEC program that investigated the trophodynamic structure and function of the Baltic and North Seas under the influence of physical forcing. This review summarizes literature on the ecophysiology of sprat with an emphasis on describing how environmental factors influence the life-history strategy of this small pelagic fish. Ontogenetic changes in feeding and growth, and the impacts of abiotic and biotic factors on vital rates are discussed with particular emphasis on the role of temperature as a constraint to life-history scheduling of this species in the Baltic Sea. A combination of field and laboratory data suggests that optimal thermal windows for growth and survival change during early life and are wider for eggs (5-17 °C) than in young (8- to 12-mm) early feeding larvae (5-12 °C). As larvae become able to successfully capture larger prey, thermal windows expand to include warmer waters. For example, 12- to 16-mm larvae can grow well at 16 °C and larger, transitional-larvae and early juveniles display the highest rates of feeding and growth at ∼18-22 °C. Gaps in knowledge are identified including the need for additional laboratory studies on the physiology and behavior of larvae (studies that will be particularly critical for biophysical modeling activities) and research addressing the role of overwinter survival as a factor shaping phenology and setting limits on the productivity of this species in areas located at the northern limits of its latitudinal range (such as the Baltic Sea). Based on stage- and temperature-specific mortality and growth potential of early life stages, our analysis suggests that young-of-the year sprat would benefit from inhabiting warmer, near-shore environments rather than the deeper-water spawning grounds such as the Bornholm Basin (central Baltic Sea). Utilization of warmer, nearshore waters (or a general increase in Baltic Sea temperatures) is

  8. Analysing water level trends and extremes in the Baltic Sea for the period 1950-2015

    NASA Astrophysics Data System (ADS)

    Gräwe, Ulf; Klingbeil, Knut

    2016-04-01

    The General Estuarine Transport Model (GETM) was applied to create a state estimate of the Baltic Sea for the period 1950-2015 with a horizontal resolution of 1 nautical mile . In the vertical 60 terrain-following layers were used, which during runtime automatically adapt to the highly variable stratification. This is associated with sporadicly inflowing bottom gravity currents of saline North Sea water, the seasonal thermocline and internal wave motions at the permanent halocline. These challenges need to be tackled by a model to correctly reproduce the mixing and entrainment of water masses in the Baltic Sea. The atmospheric forcing was taken from a regional reanalysis with a spatial resolution of less than 20 km and hourly values. The analysis of the sea surface height (SSH) revealed a non-uniform absolute mean sea level (MSL) rise in the Baltic Sea. Lowest values are found in the western part with 1.4mm/year and highest values in the Gulf of Finland with values of 2.2 mm/year. This spatial heterogeneity is partially explained by an increase in the mean zonal winds but also by changes in air pressure. The warming trend of the sea surface temperature adds to the regional increase in SSH. Analysing water level extremes, the simulations indicate a much faster rise in annual maximum SSH compared to MSL rise. This is well correlated with an increase in the annual maximum wind speed. The linear trends in annual maximum SSH are 2 mm/year in the western Baltic Sea and reach peak values of 6 mm/year in the Gulf of Finland. For the trends in annual minimum SSH we do not see any trend different from MSL rise. As a further measure to quantify changes in extreme water levels, we computed the duration and intensity (duration times excess water height over 99 percentile). Whereas the mean duration does not change significantly, the model results indicate a significant increase in intensity. To estimate the robustness of the results, their sensitivity to the atmospheric forcing

  9. The Baltic Sea: Geophysical and geochemical properties of Holocene sediment sequences as indicators of past environmental variability

    NASA Astrophysics Data System (ADS)

    Lenz, Conny; Reinholdsson, Maja; Zillén, Lovisa; Conley, Daniel J.; Snowball, Ian

    2010-05-01

    The Baltic Sea has undergone large environmental changes since the retreat of the Weischselian Ice-sheet. In the Late Glacial Period and the early Holocene these changes were most likely caused by natural environmental changes (i.e. changes in the morphology and depths of the Baltic basin and the sills). In more recent time anthropogenic impacts have become more important as a possible and likely cause for changes. During the whole Holocene period climate variability played an important role. However, the relative importance between humans and nature is largely unknown. Here we present the results of a combined geophysical and geochemical study on selected sediment sequences from the Baltic Sea within the two BONUS (Baltic Organisations Network For Funding Science) funded projects HYPER (HYPoxia mitigation for Baltic Sea Ecosystem Restoration) and Baltic GAS (GAS storage and effects of climate change and eutrophication). The over-all aim of these projects is to understand large-scale Baltic Sea ecosystem responses to environmental, climate and anthropogenic forcing. During two Baltic Sea research cruises in 2009 long sediment cores from 8 different locations were recovered. We present preliminary results from one site (LL19) located in the north central Baltic Proper at 169 m water depth. The Littorina Sea sediment record (i.e. the last c. 8000 years) is characterised by alternating periods of homogenised sediments (indicative of oxic conditions) and laminated sediments (indicative of hypoxic/anoxic conditions). Mineral magnetic properties illustrate clear changes between laminated and non-laminated sections of the core. The concentration of ferrimagnetic minerals, as revealed by initial magnetic susceptibility (χ) and saturation isothermal remanent magnetization (SIRM) is variable. The laminated sections in particular show high concentrations and to reveal the origin of the ferrimagnetic signal additional magnetic properties were measured, specifically the

  10. Parasitation of sea trout (Salmo trutta trutta L.) from the spawning ground and German coastal waters off Mecklenburg-Western Pomerania, Baltic Sea.

    PubMed

    Unger, Patrick; Palm, Harry W

    2016-01-01

    A total of 52 sea trouts, Salmo trutta trutta, were studied for parasites, originating from German freshwater streams and coastal waters of the Baltic Sea. While 35 specimens were caught mainly close to the shoreline in the Baltic Sea, 17 were sampled during their spawning migration in Warnow River and other neighboring rivers in Mecklenburg-Western Pomerania. A total of 12 different metazoan parasite species were found in sea trout originating from the Baltic Sea, including five digeneans, two cestodes, three nematodes, and two acanthocephalans. Marine and freshwater species were found. In the migratory trout, seven different parasite species were recorded (one digenean, two cestodes, one nematode, and one acanthocephalan), demonstrating lower parasite diversity and load during the spawning migration compared with the fish from the Baltic Sea. The anisakid nematodes Anisakis simplex (sensu stricto), Contraceacum rudolphii, and Hysterothylacium aduncum were identified by molecular analyses of the ITS-1, 5.8S, ITS-2, and flanking sequences of the rDNA. Together with the digenean Derogenes varicus, Hemiurus communis and H. luehei, and the cestode Diphyllobothrium dendriticum seven new host records for sea trout from the German part of the Baltic Sea are made.

  11. Parasitation of sea trout (Salmo trutta trutta L.) from the spawning ground and German coastal waters off Mecklenburg-Western Pomerania, Baltic Sea.

    PubMed

    Unger, Patrick; Palm, Harry W

    2016-01-01

    A total of 52 sea trouts, Salmo trutta trutta, were studied for parasites, originating from German freshwater streams and coastal waters of the Baltic Sea. While 35 specimens were caught mainly close to the shoreline in the Baltic Sea, 17 were sampled during their spawning migration in Warnow River and other neighboring rivers in Mecklenburg-Western Pomerania. A total of 12 different metazoan parasite species were found in sea trout originating from the Baltic Sea, including five digeneans, two cestodes, three nematodes, and two acanthocephalans. Marine and freshwater species were found. In the migratory trout, seven different parasite species were recorded (one digenean, two cestodes, one nematode, and one acanthocephalan), demonstrating lower parasite diversity and load during the spawning migration compared with the fish from the Baltic Sea. The anisakid nematodes Anisakis simplex (sensu stricto), Contraceacum rudolphii, and Hysterothylacium aduncum were identified by molecular analyses of the ITS-1, 5.8S, ITS-2, and flanking sequences of the rDNA. Together with the digenean Derogenes varicus, Hemiurus communis and H. luehei, and the cestode Diphyllobothrium dendriticum seven new host records for sea trout from the German part of the Baltic Sea are made. PMID:26374539

  12. (137)Cs, (40)K and (210)Po in marine mammals from the southern Baltic Sea.

    PubMed

    Ciesielski, Tomasz; Góral, Marta; Szefer, Piotr; Jenssen, Bjørn Munro; Bojanowski, Ryszard

    2015-12-15

    This study provides information on baseline concentrations of the radionuclides Cesium-137, Potassium-40 and Polonium-210 in sea mammals from the Baltic Sea. The radionuclides were analyzed in the liver, kidney and muscle of harbor porpoises, striped dolphins, and gray and ringed seals from the Polish coast by γ- and α-spectrometry. Median (137)Cs activities were 14.8, 13.2 and 23.2 Bq kg(-1) w.w. in the liver, kidney and muscles, respectively. Activities of (40)K and (210)Po in the respective tissues were found to be 79.1, 79.8 and 111 Bq kg(-1) for (40)K and 58.1, 59.2 and 32.9 Bq kg(-1) for (210)Po. The measured (137)Cs concentrations were extraordinarily high in comparison to those reported in sea mammals from other locations. However, dose assessments did not imply health effects from (137)Cs exposure in Baltic Sea mammals. Correlations between (137)Cs tissue activities and reported sea water concentrations highlight the potential use of marine mammals for biomonitoring purposes. PMID:26456908

  13. (137)Cs, (40)K and (210)Po in marine mammals from the southern Baltic Sea.

    PubMed

    Ciesielski, Tomasz; Góral, Marta; Szefer, Piotr; Jenssen, Bjørn Munro; Bojanowski, Ryszard

    2015-12-15

    This study provides information on baseline concentrations of the radionuclides Cesium-137, Potassium-40 and Polonium-210 in sea mammals from the Baltic Sea. The radionuclides were analyzed in the liver, kidney and muscle of harbor porpoises, striped dolphins, and gray and ringed seals from the Polish coast by γ- and α-spectrometry. Median (137)Cs activities were 14.8, 13.2 and 23.2 Bq kg(-1) w.w. in the liver, kidney and muscles, respectively. Activities of (40)K and (210)Po in the respective tissues were found to be 79.1, 79.8 and 111 Bq kg(-1) for (40)K and 58.1, 59.2 and 32.9 Bq kg(-1) for (210)Po. The measured (137)Cs concentrations were extraordinarily high in comparison to those reported in sea mammals from other locations. However, dose assessments did not imply health effects from (137)Cs exposure in Baltic Sea mammals. Correlations between (137)Cs tissue activities and reported sea water concentrations highlight the potential use of marine mammals for biomonitoring purposes.

  14. Responses of Baltic Sea ice and open-water natural bacterial communities to salinity change.

    PubMed

    Kaartokallio, Hermanni; Laamanen, Maria; Sivonen, Kaarina

    2005-08-01

    To investigate the responses of Baltic Sea wintertime bacterial communities to changing salinity (5 to 26 practical salinity units), an experimental study was conducted. Bacterial communities of Baltic seawater and sea ice from a coastal site in southwest Finland were used in two batch culture experiments run for 17 or 18 days at 0 degrees C. Bacterial abundance, cell volume, and leucine and thymidine incorporation were measured during the experiments. The bacterial community structure was assessed using denaturing gradient gel electrophoresis (DGGE) of PCR-amplified partial 16S rRNA genes with sequencing of DGGE bands from initial communities and communities of day 10 or 13 of the experiment. The sea ice-derived bacterial community was metabolically more active than the open-water community at the start of the experiment. Ice-derived bacterial communities were able to adapt to salinity change with smaller effects on physiology and community structure, whereas in the open-water bacterial communities, the bacterial cell volume evolution, bacterial abundance, and community structure responses indicated the presence of salinity stress. The closest relatives for all eight partial 16S rRNA gene sequences obtained were either organisms found in polar sea ice and other cold habitats or those found in summertime Baltic seawater. All sequences except one were associated with the alpha- and gamma-proteobacteria or the Cytophaga-Flavobacterium-Bacteroides group. The overall physiological and community structure responses were parallel in ice-derived and open-water bacterial assemblages, which points to a linkage between community structure and physiology. These results support previous assumptions of the role of salinity fluctuation as a major selective factor shaping the sea ice bacterial community structure.

  15. Sensitivity of modeled atmospheric nitrogen species and nitrogen deposition to variations in sea salt emissions in the North Sea and Baltic Sea regions

    NASA Astrophysics Data System (ADS)

    Neumann, Daniel; Matthias, Volker; Bieser, Johannes; Aulinger, Armin; Quante, Markus

    2016-03-01

    Coarse sea salt particles are emitted ubiquitously from the ocean surface by wave-breaking and bubble-bursting processes. These particles impact the atmospheric chemistry by affecting the condensation of gas-phase species and, thus, indirectly the nucleation of new fine particles, particularly in regions with significant air pollution. In this study, atmospheric particle concentrations are modeled for the North Sea and Baltic Sea regions in northwestern Europe using the Community Multiscale Air Quality (CMAQ) modeling system and are compared to European Monitoring and Evaluation Programme (EMEP) measurement data. The sea salt emission module is extended by a salinity-dependent scaling of the sea salt emissions because the salinity in large parts of the Baltic Sea is very low, which leads to considerably lower sea salt mass emissions compared to other oceanic regions. The resulting improvement in predicted sea salt concentrations is assessed. The contribution of surf zone emissions is considered separately. Additionally, the impacts of sea salt particles on atmospheric nitrate and ammonium concentrations and on nitrogen deposition are evaluated. The comparisons with observational data show that sea salt concentrations are commonly overestimated at coastal stations and partly underestimated farther inland. The introduced salinity scaling improves the predicted Baltic Sea sea salt concentrations considerably. The dates of measured peak concentrations are appropriately reproduced by the model. The impact of surf zone emissions is negligible in both seas. Nevertheless, they might be relevant because surf zone emissions were cut at an upper threshold in this study. Deactivating sea salt leads to minor increases in NH3 + NH4+ and HNO3 + NO3- and a decrease in NO3- concentrations. However, the overall effect on NH3 + NH4+ and HNO3 + NO3- concentrations is smaller than the deviation from the measurements. Nitrogen wet deposition is underestimated by the model at most

  16. Modelling the influence of climate change on the chemical concentrations in the Baltic Sea region with the POPCYCLING-Baltic model.

    PubMed

    Kong, Deguo; MacLeod, Matthew; Cousins, Ian T

    2014-09-01

    The effect of projected future changes in temperature, wind speed, precipitation and particulate organic carbon on concentrations of persistent organic chemicals in the Baltic Sea regional environment is evaluated using the POPCYCLING-Baltic multimedia chemical fate model. Steady-state concentrations of hypothetical perfectly persistent chemicals with property combinations that encompass the entire plausible range for non-ionizing organic substances are modelled under two alternative climate change scenarios (IPCC A2 and B2) and compared to a baseline climate scenario. The contributions of individual climate parameters are deduced in model experiments in which only one of the four parameters is changed from the baseline scenario. Of the four selected climate parameters, temperature is the most influential, and wind speed is least. Chemical concentrations in the Baltic region are projected to change by factors of up to 3.0 compared to the baseline climate scenario. For chemicals with property combinations similar to legacy persistent organic pollutants listed by the Stockholm Convention, modelled concentration ratios between two climate change scenarios and the baseline scenario range from factors of 0.5 to 2.0. This study is a first step toward quantitatively assessing climate change-induced changes in the environmental concentrations of persistent organic chemicals in the Baltic Sea region.

  17. Helmintofauna of turbot Scophthalmus maximus (Linnaeus, 1758) from the southern Baltic Sea including new data.

    PubMed

    Skrzypczak, M; Rolbiecki, L

    2015-01-01

    Turbot Scophthalmus maximus (Linnaeus, 1758) is a fish belonging to the Pleuronectiformes order. It is commonly observed in waters of the northern Atlantic, and also in the Baltic Sea. As an economically significant species, it is fished on an industrial scale, and also farmed in some European countries. Seventy-two turbots from the Gulf of Gdańsk (26th ICES zone) were examined for parasite presence in the years 2010-2012. The study revealed the presence of the tapeworm Bothriocephalus scorpii (Müller, 1776) and acanthocephalan Corynosoma semerme (Forssell, 1904). The overall (both parasites) prevalence of turbot infection was 100% with a mean intensity of 18.7. C. semerme is a parasite which has not been noted so far in turbot from the southern Baltic. The presence of C. semerme in turbot was emphasized in the context of possible infection of terrestrial mammals, including humans. PMID:26618593

  18. Virulence Profiles of Vibrio vulnificus in German Coastal Waters, a Comparison of North Sea and Baltic Sea Isolates.

    PubMed

    Bier, Nadja; Jäckel, Claudia; Dieckmann, Ralf; Brennholt, Nicole; Böer, Simone I; Strauch, Eckhard

    2015-12-01

    Vibrio vulnificus is a halophilic bacterium of coastal environments known for sporadically causing severe foodborne or wound infections. Global warming is expected to lead to a rising occurrence of V. vulnificus and an increasing incidence of human infections in Northern Europe. So far, infections in Germany were exclusively documented for the Baltic Sea coast, while no cases from the North Sea region have been reported. Regional variations in the prevalence of infections may be influenced by differences in the pathogenicity of V. vulnificus populations in both areas. This study aimed to compare the distribution of virulence-associated traits and genotypes among 101 V. vulnificus isolates from the Baltic Sea and North Sea in order to assess their pathogenicity potential. Furthermore, genetic relationships were examined by multilocus sequence typing (MLST). A high diversity of MLST sequences (74 sequence types) and differences regarding the presence of six potential pathogenicity markers were observed in the V. vulnificus populations of both areas. Strains with genotypes and markers associated with pathogenicity are not restricted to a particular geographic region. This indicates that lack of reported cases in the North Sea region is not caused by the absence of potentially pathogenic strains.

  19. Virulence Profiles of Vibrio vulnificus in German Coastal Waters, a Comparison of North Sea and Baltic Sea Isolates.

    PubMed

    Bier, Nadja; Jäckel, Claudia; Dieckmann, Ralf; Brennholt, Nicole; Böer, Simone I; Strauch, Eckhard

    2015-12-01

    Vibrio vulnificus is a halophilic bacterium of coastal environments known for sporadically causing severe foodborne or wound infections. Global warming is expected to lead to a rising occurrence of V. vulnificus and an increasing incidence of human infections in Northern Europe. So far, infections in Germany were exclusively documented for the Baltic Sea coast, while no cases from the North Sea region have been reported. Regional variations in the prevalence of infections may be influenced by differences in the pathogenicity of V. vulnificus populations in both areas. This study aimed to compare the distribution of virulence-associated traits and genotypes among 101 V. vulnificus isolates from the Baltic Sea and North Sea in order to assess their pathogenicity potential. Furthermore, genetic relationships were examined by multilocus sequence typing (MLST). A high diversity of MLST sequences (74 sequence types) and differences regarding the presence of six potential pathogenicity markers were observed in the V. vulnificus populations of both areas. Strains with genotypes and markers associated with pathogenicity are not restricted to a particular geographic region. This indicates that lack of reported cases in the North Sea region is not caused by the absence of potentially pathogenic strains. PMID:26694432

  20. Virulence Profiles of Vibrio vulnificus in German Coastal Waters, a Comparison of North Sea and Baltic Sea Isolates

    PubMed Central

    Bier, Nadja; Jäckel, Claudia; Dieckmann, Ralf; Brennholt, Nicole; Böer, Simone I.; Strauch, Eckhard

    2015-01-01

    Vibrio vulnificus is a halophilic bacterium of coastal environments known for sporadically causing severe foodborne or wound infections. Global warming is expected to lead to a rising occurrence of V. vulnificus and an increasing incidence of human infections in Northern Europe. So far, infections in Germany were exclusively documented for the Baltic Sea coast, while no cases from the North Sea region have been reported. Regional variations in the prevalence of infections may be influenced by differences in the pathogenicity of V. vulnificus populations in both areas. This study aimed to compare the distribution of virulence-associated traits and genotypes among 101 V. vulnificus isolates from the Baltic Sea and North Sea in order to assess their pathogenicity potential. Furthermore, genetic relationships were examined by multilocus sequence typing (MLST). A high diversity of MLST sequences (74 sequence types) and differences regarding the presence of six potential pathogenicity markers were observed in the V. vulnificus populations of both areas. Strains with genotypes and markers associated with pathogenicity are not restricted to a particular geographic region. This indicates that lack of reported cases in the North Sea region is not caused by the absence of potentially pathogenic strains. PMID:26694432

  1. How will ocean acidification affect Baltic sea ecosystems? an assessment of plausible impacts on key functional groups.

    PubMed

    Havenhand, Jonathan N

    2012-09-01

    Increasing partial pressure of atmospheric CO₂ is causing ocean pH to fall-a process known as 'ocean acidification'. Scenario modeling suggests that ocean acidification in the Baltic Sea may cause a ≤ 3 times increase in acidity (reduction of 0.2-0.4 pH units) by the year 2100. The responses of most Baltic Sea organisms to ocean acidification are poorly understood. Available data suggest that most species and ecologically important groups in the Baltic Sea food web (phytoplankton, zooplankton, macrozoobenthos, cod and sprat) will be robust to the expected changes in pH. These conclusions come from (mostly) single-species and single-factor studies. Determining the emergent effects of ocean acidification on the ecosystem from such studies is problematic, yet very few studies have used multiple stressors and/or multiple trophic levels. There is an urgent need for more data from Baltic Sea populations, particularly from environmentally diverse regions and from controlled mesocosm experiments. In the absence of such information it is difficult to envision the likely effects of future ocean acidification on Baltic Sea species and ecosystems.

  2. Polychlorinated biphenyls (PCBs) in sediments of the southern Baltic Sea--trends and fate.

    PubMed

    Konat, J; Kowalewska, G

    2001-12-01

    Polychlorinated biphenyls (PCBs) have been determined in recent [0-1(2), 1(2)-5 and 5-10 cm deep layers] sediments from different sites of the southern Baltic Sea, including the Szczecin Lagoon, collected from May 1996 to October 1999, i.e. before and after the great flood in Poland of July/August 1997. The PCB distribution has been correlated with location and hydrological conditions as well as with organic carbon, algal pigments and their derivatives in the sediments. The sum of PCB (seven congeners) was equal to approximately 1-149 ng/g dry wt., on average this was rather low (up to 40 ng/g). There was a decreasing trend in PCBs concentrations in the bottom sediments of the southern Baltic in 1996 but considerable amounts were still accumulated there. The flood of 1997 caused a distinct increase of PCB concentration level in the sediments, which again showed a decreasing trend in the next few years. This illustrates that at present the main source of PCBs for the southern Baltic are not a direct consequence of human activity, but from floods and heavy rains washing these compounds from land to the sea. Algae and algal detritus play an important role in the transport and distribution of PCBs in the southern Baltic. High correlation of PCBs with chlorophyll a derivatives--products of zooplankton grazing--indicates that PCBs are ingested by zooplankton with phytoplankton and then exuded with fecal pellets. PCBs bound to algal detritus or to fecal pellets in the water column are transferred to sediments, there they may be trapped either in a bonded and unchanged form or resuspended, remobilized and/or dechlorinated, depending on their properties and environmental conditions. PMID:11763260

  3. Air-water exchange of brominated anisoles in the northern Baltic Sea.

    PubMed

    Bidleman, Terry F; Agosta, Kathleen; Andersson, Agneta; Haglund, Peter; Nygren, Olle; Ripszam, Matyas; Tysklind, Mats

    2014-06-01

    Bromophenols produced by marine algae undergo O-methylation to form bromoanisoles (BAs), which are exchanged between water and air. BAs were determined in surface water of the northern Baltic Sea (Gulf of Bothnia, consisting of Bothnian Bay and Bothnian Sea) during 2011-2013 and on a transect of the entire Baltic in September 2013. The abundance decreased in the following order: 2,4,6-tribromoanisole (2,4,6-TBA)>2,4-dibromoanisole (2,4-DBA)≫2,6-dibromoanisole (2,6-DBA). Concentrations of 2,4-DBA and 2,4,6-TBA in September were higher in the southern than in the northern Baltic and correlated well with the higher salinity in the south. This suggests south-to-north advection and dilution with fresh riverine water enroute, and/or lower production in the north. The abundance in air over the northern Baltic also decreased in the following order: 2,4,6-TBA>2,4-DBA. However, 2,6-DBA was estimated as a lower limit due to breakthrough from polyurethane foam traps used for sampling. Water/air fugacity ratios ranged from 3.4 to 7.6 for 2,4-DBA and from 18 to 94 for 2,4,6-TBA, indicating net volatilization. Flux estimates using the two-film model suggested that volatilization removes 980-1360 kg of total BAs from Bothnian Bay (38000 km2) between May and September. The release of bromine from outgassing of BAs could be up to 4-6% of bromine fluxes from previously reported volatilization of bromomethanes and bromochloromethanes.

  4. Assimilating NOAA SST data into BSH operational circulation model for North and Baltic Seas

    NASA Astrophysics Data System (ADS)

    Losa, Svetlana; Schroeter, Jens; Nerger, Lars; Janjic, Tijana; Danilov, Sergey; Janssen, Frank

    A data assimilation (DA) system is developed for BSH operational circulation model in order to improve forecast of current velocities, sea surface height, temperature and salinity in the North and Baltic Seas. Assimilated data are NOAA sea surface temperature (SST) data for the following period: 01.10.07 -30.09.08. All data assimilation experiments are based on im-plementation of one of the so-called statistical DA methods -Singular Evolutive Interpolated Kalman (SEIK) filter, -with different ways of prescribing assumed model and data errors statis-tics. Results of the experiments will be shown and compared against each other. Hydrographic data from MARNET stations and sea level at series of tide gauges are used as independent information to validate the data assimilation system. Keywords: Operational Oceanography and forecasting

  5. Baroclinic internal wave energy distribution in the Baltic Sea derived from 45 years of circulation simulations

    NASA Astrophysics Data System (ADS)

    Rybin, Artem; Soomere, Tarmo; Kurkina, Oxana; Kurkin, Andrey; Rouvinskaya, Ekaterina; Markus Meier, H. E.

    2016-04-01

    Internal waves and internal tides are an essential component of the functioning of stratified shelf seas. They carry substantial amounts of energy through the water masses, drive key hydrophysical processes such as mixing and overturning and support the functioning of marine ecosystem in many ways. Their particular impact becomes evident near and at the bottom where they often create substantial loads to engineering structures and exert a wide range of impacts on the bottom sediments and evolution of the seabed. We analyse several properties of spatio-temporal distributions of energy of relatively long-period large-scale internal wave motions in the Baltic Sea. The analysis is based on numerically simulated pycnocline variations that are extracted from the hydrographic data calculated by the Rossby Centre Ocean circulation model (RCO) for the entire Baltic Sea for 1961-2005. This model has a horizontal resolution of 2 nautical miles and uses 41 vertical layers with a thickness between 3 m close to the surface and 12 m in 250 m depth. The model is forced with atmospheric data derived from the ERA-40 re-analysis using a regional atmosphere model with a horizontal resolution of 25 km. It also accounts for river inflow and water exchange through the Danish Straits. See (Meier, H.E.M., Höglund, A., 2013. Studying the Baltic Sea circulation with Eulerian tracers, in Soomere, T., Quak, E., eds., Preventive Methods for Coastal Protection, Springer, Cham, Heidelberg, 101-130) for a detailed description of the model and its forcing. The resolution of the model output used in this study (once in 6 hours) is sufficient for estimates of spectral amplitudes of the displacements of isopycnal surfaces with a typical period of 2-12 days. We provide the analysis of kinetic and potential energy of motions with these periods. The resulting maps of the maxima of energy and spatial distributions of near-bottom velocities have been evaluated for the entire simulation interval of 45

  6. Prediction of near-bottom water salinity in the Baltic Sea using Ordinary Least Squares and Geographically Weighted Regression models

    NASA Astrophysics Data System (ADS)

    Łukawska-Matuszewska, Katarzyna; Urbański, Jacek Andrzej

    2014-08-01

    A map of spatial salinity distribution in the bottom water layers of the Baltic Sea is presented in this paper. The map has been constructed based on the data obtained from the ICES Dataset on Ocean Hydrography. The typical salinity values and the depth of halocline location in the major basins of the Baltic Sea are also presented. While the spatial salinity distribution is commonly derived by interpolation from the available data set, the linear regression model has been applied in this work. The analyzed data cover the period between 1913 and 2011, with a spatial resolution of ca. 10 km. In order to prepare the salinity map for the bottom water layers in the Baltic, the relationships between the salinity, depth and the distance from the Danish Straits have been determined by using Geographically Weighted Regression (GWR). Next, the salinity map was created by using the maps of regression coefficients, the digital elevation model (DEM) of the Baltic Sea, and the map of Euclidean distance from the Danish Straits. Subsequently the salinity values in the water layer above and below the halocline that are typical for the specific Baltic basins as well as the depth of location of the halocline were calculated based on the data extracted from the map by random point sampling. The calculated salinity values for the upper layer were similar to the values reported in the current publications on the subject of the Baltic Sea. On the other hand, the obtained salinity values for the layer below the halocline were slightly lower than those found in the literature, which is attributable to different methodology used. The obtained results demonstrate that GWR is a reliable tool for estimating the natural variation of salinity in the Baltic Sea. At the same time, we conclude that the Ordinary Least Squares regression should not be used to analyze similar data.

  7. Carbon flows in Baltic Sea food webs — a re-evaluation using a mass balance approach

    NASA Astrophysics Data System (ADS)

    Sandberg, J.; Elmgren, R.; Wulff, F.

    2000-07-01

    The brackish Baltic Sea has been seen as particularly suitable for studies of food webs. Compared to fully marine ecosystems, it has low species diversity, which means fewer trophic linkages to analyse. The Baltic Sea is also one of the best-studied areas of the world, suggesting that most data requirements for food web models should be fulfilled. Nevertheless, the influence of physical and biological factors on trophic interactions and biogeochemical patterns varies spatially in the Baltic Sea, adding considerable complexity to food web studies. Food web structure and processes can be described and compared quantitatively between areas by estimating the flow of matter or energy through the organisms. Most such models have been based on carbon, though studies of complementary flows of other elements limiting production, such as nitrogen and phosphorus would be desirable. However, since ratios between carbon and other elements are used in calculating these flows, it is crucial, as a first step, to quantify the flows of carbon as accurately as possible. In this study, we used the EcopathII software (ver 3.1) to analyse models of carbon flow through the food webs in the three main areas of the Baltic Sea; the Baltic proper, Bothnian Sea and Bothnian Bay. A previously published study on carbon flow in the Baltic Sea [Elmgren, R. 1984. Trophic dynamics in the enclosed, brackish Baltic Sea. Rapp. P.-V. Reun. — Cons. Int. Explor. Mer. (183) 152-169.] was complemented with the data on respiration and flow to detritus [Wulff, F., Ulanowicz, R. 1989. A comparative anatomy of the Baltic Sea and Chesapeeake Bay ecosystems. In: F. Wulff, J.G. Field, K.H. Mann (Eds.), Flow Analysis of Marine Ecosystems: Theory and Practice. New York: Springer-Verlag.] in order to present complete mass balance models of carbon. The purpose of re-evaluating previous models with new analytic tools was to check how well their carbon flows balance, and to provide a basis for improved mass balance

  8. A probabilistic storm surge risk model for the German North Sea and Baltic Sea coast

    NASA Astrophysics Data System (ADS)

    Grabbert, Jan-Henrik; Reiner, Andreas; Deepen, Jan; Rodda, Harvey; Mai, Stephan; Pfeifer, Dietmar

    2010-05-01

    The German North Sea coast is highly exposed to storm surges. Due to its concave bay-like shape mainly orientated to the North-West, cyclones from Western, North-Western and Northern directions together with astronomical tide cause storm surges accumulating the water in the German bight. Due to the existence of widespread low-lying areas (below 5m above mean sea level) behind the defenses, large areas including large economic values are exposed to coastal flooding including cities like Hamburg or Bremen. The occurrence of extreme storm surges in the past like e.g. in 1962 taking about 300 lives and causing widespread flooding and 1976 raised the awareness and led to a redesign of the coastal defenses which provide a good level of protection for today's conditions. Never the less the risk of flooding exists. Moreover an amplification of storm surge risk can be expected under the influence of climate change. The Baltic Sea coast is also exposed to storm surges, which are caused by other meteorological patterns. The influence of the astronomical tide is quite low instead high water levels are induced by strong winds only. Since the exceptional extreme event in 1872 storm surge hazard has been more or less forgotten. Although such an event is very unlikely to happen, it is not impossible. Storm surge risk is currently (almost) non-insurable in Germany. The potential risk is difficult to quantify as there are almost no historical losses available. Also premiums are difficult to assess. Therefore a new storm surge risk model is being developed to provide a basis for a probabilistic quantification of potential losses from coastal inundation. The model is funded by the GDV (German Insurance Association) and is planned to be used within the German insurance sector. Results might be used for a discussion of insurance cover for storm surge. The model consists of a probabilistic event driven hazard and a vulnerability module, furthermore an exposure interface and a financial

  9. Holocene Sedimentation in the Ångermanälven River Estuary, the northern Baltic Sea

    NASA Astrophysics Data System (ADS)

    Kotilainen, Aarno; Hyttinen, Outi; Obrochta, Stephen; Andrén, Thomas; Ryabchuk, Daria; Snowball, Ian; IODP Expedition 347 Science Party, The

    2015-04-01

    In the IODP Expedition 347 - "Baltic Sea Paleoenvironment" - two sites in the Ångermanälven River estuary were drilled. Sites M0061 and M0062 are located at about 62°47'N, in an area which was deglaciated ca. 10 ka ago. It has long been known that varve deposition is an ongoing process in Ångermanälven estuary, and that it has continued so several thousand years back in time. It has also been shown that a correlation exists between maximum daily discharge and mean varve thickness at least AD 1901-1971 in the Ångermanälven River (Sander et al. 2002). Studying varve thickness and sediment geochemistry potentially yield estimations on past changes in precipitation and sedimentation processes in the estuary. In this presentation, the preliminary results from site M0062 are shown. The core recovery was approximately 36 m and the sediment sequence was divided into two lithological units (Expedition 347 Scientists, 2014). The lowest Unit 2 (17.09-35.9 mbsf) consists of well-sorted sand, deposited by a (glacio)fluvial system. Unit 1 (0-17.09 mbsf) showed transition from glacial lake varves to brackish marine couplets. The uppermost 18 metres were analysed for grain-size and elemental geochemistry every 0.3-0.5 m. From selected intervals, a 1mm-resolution XRF-scanning of the split core surface was done to compare changes in the relative abundance of light elements. Results from Ångermanälven were compared with measurements from glacial varved sediments, retrieved from the eastern Gulf of Finland. This work is also part of "Climate - ice sheet - sea interactions - evolution of the Baltic Sea Basin over the past 60000 years (CISU)" which is a new joint research project with The Academy of Finland and The Russian Foundation for Basic Research. The CISU project is coordinated by Geological Survey of Finland and the other partners are Helsinki University and A.P. Karpinsky Russian Geological Research Institute (VSEGEI), Russia. The project bases on the IODP Expedition

  10. Eutrophication status of the North Sea, Skagerrak, Kattegat and the Baltic Sea in present and future climates: A model study

    NASA Astrophysics Data System (ADS)

    Skogen, Morten D.; Eilola, Kari; Hansen, Jørgen L. S.; Meier, H. E. Markus; Molchanov, Mikhail S.; Ryabchenko, Vladimir A.

    2014-04-01

    A method to combine observations and an ensemble of ecological models has been used to assess eutrophication. Using downscaled forcing from two GCMs under the A1B emission scenario, an assessment of the eutrophication status was made for a control (1970-2000) and a future climate (2070-2100) period. By using validation results from a hindcast to compute individual weights between the models, an assessment of eutrophication is done using a set of threshold values. The final classification distinguishes between three categories: problem area, potential problem area, and non-problem area, in accordance with current management practice as suggested by the Oslo and Paris Commissions (OSPAR) and the Helsinki Commission (HELCOM). For the control run the assessment indicates that the Kattegat, the Danish Straits, the Gulf of Finland, the Gotland Basin as well as main parts of the Arkona Basin, the Bornholm Basin, and the Baltic proper may be classified as problem areas. The main part of the North Sea and also the Skagerrak are non-problem areas while the main parts of the Gulf of Bothnia, Gulf of Riga and the entire southeastern continental coast of the North Sea may be classified as potential problem areas. In the future climate scenarios most of the previous potential problem areas in the Baltic Sea have become problem areas, except for the Bothnian Bay where the situation remain fairly unchanged. In the North Sea there seems to be no obvious changes in eutrophication status in the projected future climate.

  11. Development of tools for integrated monitoring and assessment of hazardous substances and their biological effects in the Baltic Sea.

    PubMed

    Lehtonen, Kari K; Sundelin, Brita; Lang, Thomas; Strand, Jakob

    2014-02-01

    The need to develop biological effects monitoring to facilitate a reliable assessment of hazardous substances has been emphasized in the Baltic Sea Action Plan of the Helsinki Commission. An integrated chemical-biological approach is vitally important for the understanding and proper assessment of anthropogenic pressures and their effects on the Baltic Sea. Such an approach is also necessary for prudent management aiming at safeguarding the sustainable use of ecosystem goods and Services. The BEAST project (Biological Effects of Anthropogenic Chemical Stress: Tools for the Assessment of Ecosystem Health) set out to address this topic within the BONUS Programme. BEAST generated a large amount of quality-assured data on several biological effects parameters (biomarkers) in various marine species in different sub-regions of the Baltic Sea. New indicators (biological response measurement methods) and management tools (integrated indices) with regard to the integrated monitoring approach were suggested.

  12. Shell form, growth, and production of Astarte borealis (Schumacher, 1817) (Astartidae, Bivalvia) in the southeastern Baltic Sea

    NASA Astrophysics Data System (ADS)

    Gusev, A. A.; Rudinskaya, L. V.

    2014-07-01

    The relationships between the linear dimensions and body weight and the ratio between the masses, growth, and production were studied for the bivalve Astarte borealis inhabiting the southeastern Baltic Sea. The maximal shell length was 21.09 mm, while the maximum age was 8+. The linear growth was described by the Bertalanffy equation L τ = (1 - e -0.0894(τ-(-0.7354))). The annual production was 7.60 kJ/m2 at a P s/ B coefficient of 0.41. It was found that the A. borealis inhabiting the southeastern Baltic Sea was characterized by a lower linear growth rate compared to the mollusks of other parts of the geographical range due to the low salinity of the Baltic Sea.

  13. Lack of recognition of genetic biodiversity: International policy and its implementation in Baltic Sea marine protected areas.

    PubMed

    Laikre, Linda; Lundmark, Carina; Jansson, Eeva; Wennerström, Lovisa; Edman, Mari; Sandström, Annica

    2016-10-01

    Genetic diversity is needed for species' adaptation to changing selective pressures and is particularly important in regions with rapid environmental change such as the Baltic Sea. Conservation measures should consider maintaining large gene pools to maximize species' adaptive potential for long-term survival. In this study, we explored concerns regarding genetic variation in international and national policies that governs biodiversity and evaluated if and how such policy is put into practice in management plans governing Baltic Sea Marine Protected Areas (MPAs) in Sweden, Finland, Estonia, and Germany. We performed qualitative and quantitative textual analysis of 240 documents and found that agreed international and national policies on genetic biodiversity are not reflected in management plans for Baltic Sea MPAs. Management plans in all countries are largely void of goals and strategies for genetic biodiversity, which can partly be explained by a general lack of conservation genetics in policies directed toward aquatic environments. PMID:27098316

  14. Lack of recognition of genetic biodiversity: International policy and its implementation in Baltic Sea marine protected areas.

    PubMed

    Laikre, Linda; Lundmark, Carina; Jansson, Eeva; Wennerström, Lovisa; Edman, Mari; Sandström, Annica

    2016-10-01

    Genetic diversity is needed for species' adaptation to changing selective pressures and is particularly important in regions with rapid environmental change such as the Baltic Sea. Conservation measures should consider maintaining large gene pools to maximize species' adaptive potential for long-term survival. In this study, we explored concerns regarding genetic variation in international and national policies that governs biodiversity and evaluated if and how such policy is put into practice in management plans governing Baltic Sea Marine Protected Areas (MPAs) in Sweden, Finland, Estonia, and Germany. We performed qualitative and quantitative textual analysis of 240 documents and found that agreed international and national policies on genetic biodiversity are not reflected in management plans for Baltic Sea MPAs. Management plans in all countries are largely void of goals and strategies for genetic biodiversity, which can partly be explained by a general lack of conservation genetics in policies directed toward aquatic environments.

  15. The governance of the mitigation of the Baltic Sea eutrophication: exploring the challenges of the formal governing system.

    PubMed

    Tynkkynen, Nina; Schönach, Paula; Pihlajamäki, Mia; Nechiporuk, Dmitry

    2014-02-01

    This article focuses on the governing system of the mitigation of eutrophication in the Baltic Sea. Policies and measures of the Baltic Sea coastal countries, the macro--regional (HELCOM) level, and the level of the European Union are described and governance challenges explicated. We found that the main challenges at different governance levels include: differences between coastal countries in terms of environmental conditions including environmental awareness, overlaps of policies between different levels, the lack of adequate spatial and temporal specification of policies, and the lack of policy integration. To help to meet these challenges, we suggest closer involvement of stakeholders and the public, the improvement of the interplay of institutions, and the introduction of a "primus motor" for the governance of the mitigation of eutrophication in the Baltic Sea.

  16. Sea-level changes and the Middle-Upper Devonian sequence in the Baltic basin

    NASA Astrophysics Data System (ADS)

    Lukševičs, E.; Stinkulis, Ä.¢.

    2012-04-01

    Lithostratigraphic succession of the Middle-Upper Devonian of Baltic, represented by siliciclastic and carbonate deposits of the wide shallow epeiric sea, is well-established. The sequence of biotic and sea-level changes has been studied in detail for about half a century. However, it was rarely tried to compare the sea-level curve for the Baltic with the curve of the global sea-level changes and correlate the succession with the sequence of the Devonian global events well established mainly in the marine record. New facies analysis and biostratigraphical and taphonomical studies together with the re-evaluation of signatures of the world-wide events using sedimentological and palaeontological data enables better understanding of the development of the Middle-Late Devonian basins of the Baltic area. Indications of such events as eustatic fall of the sea-level close to the Givetian-Frasnian and Frasnian-Famennian boundaries, several small-scale transgressions during Famennian interglacials are rather clearly traceable within the sequence. Distribution of deposits, biotas and facies suggests diminishing of the depositional area since the maximum transgression in the earliest Frasnian thus demonstrating good coincidence with the global sea level curve (Haq & Schutter 2008). The retreat of depocentre of the palaeobasin in westerly direction during the late Frasnian and the Famennian likely was caused by tectonic subsidence at the western part of the east Baltics. The most significant event levels identified within the section are the extended Taghanic onlap (middle Givetian) evidenced by dolocretes in the upper part of the Burtnieki Fm; significant drop of the sea level during the earliest Frasnian indicated by widely distributed dolocretes in the top of the Amata Fm that points to the possible position of the Givetian/Frasnian boundary below the Amata; level of the Dubnik RS with extensive gypsum deposits and non-oxidised organic matter of the Salaspils Fm evidencing

  17. Trophodynamics of mercury and other trace elements in a pelagic food chain from the Baltic Sea.

    PubMed

    Nfon, Erick; Cousins, Ian T; Järvinen, Olli; Mukherjee, Arun B; Verta, Matti; Broman, Dag

    2009-12-01

    Mercury (Hg) and 13 other trace elements (Al, Ti, V, Cr, Fe, Mn, Co, Ni, Cu, Zn, As, Cd, and Pb) were measured in phytoplankton, zooplankton, mysis and herring in order to examine the trophodynamics in a well-studied pelagic food chain in the Baltic Sea. The fractionation of nitrogen isotopes (delta(15)N) was used to evaluate food web structure and to estimate the extent of trophic biomagnification of the various trace elements. Trophic magnification factors (TMFs) for each trace element were determined from the slope of the regression between trace element concentrations and delta(15)N. Calculated TMFs showed fundamental differences in the trophodynamics of the trace elements in the pelagic food chain studied. Concentrations of Al, Fe, Ni, Zn, Pb and Cd showed statistically significant decreases (TMF<1) with increasing trophic levels and thus these trace elements tropically dilute or biodilute in this Baltic food chain. Cu, As, Cr, Mn, V, Ti and Co showed no significant relationships with trophic levels. Hg was unique among the trace elements studied in demonstrating a statistically significant increase (TMF>1) in concentration with trophic level i.e. Hg biomagnifies in this Baltic food chain. The estimated TMF for Hg in this food chain was comparable to TMFs observed elsewhere for diverse food chains and locations.

  18. Improving environmental and biodiversity monitoring in the Baltic Sea using DNA barcoding of Chironomidae (Diptera).

    PubMed

    Brodin, Y; Ejdung, G; Strandberg, J; Lyrholm, T

    2013-11-01

    As for many other regions, environmental and biodiversity monitoring of the brackish Baltic Sea suffers from low species resolution for several taxa. One such case is the benthic larvae of midges Chironomidae (Diptera), which are estimated to constitute about 30% of the macrozoobenthos species of the Baltic Sea and are important indicators of environmental quality. We assessed the usefulness of COI (cytochrome oxidase I) gene barcoding to improve species resolution and its potential for implementation in monitoring programmes. Neighbour-Joining, Maximum parsimony and Bayesian-inference analyses all provided high congruency with morphological analyses of adult males for almost all 42 species studied. Barcoding was helpful to elucidate some cases of taxonomical difficulties, such as synonyms. In contrast to the high identification accuracy when using our local database, there were a number of cases where matching with GenBank and BOLD provided puzzling results. For reliable species identification at least 15-30 specimens from 5-10 well-distributed sites within the geographical range of the species might be needed in a database to adequately cover the intraspecific variability of chironomids. Implementation of DNA barcoding, as applied here, in monitoring would result in an increase from at present less than 10% to more than 90% successful chironomid species identification of Baltic Sea benthic samples, as it also would for many nearby lakes. Routine monitoring of benthic environmental samples based on Next-Generation sequencing techniques would provide a cost effective way to obtain a taxonomically much more complete assessment of environmental quality and biodiversity, as required by EU directives and national legislation.

  19. Mercury in particulate matter over Polish zone of the southern Baltic Sea

    NASA Astrophysics Data System (ADS)

    Beldowska, M.; Saniewska, D.; Falkowska, L.; Lewandowska, A.

    2012-01-01

    Important Hg transformations can occur at the air-water interface where polluted terrestrial air masses meet humid, halogen-rich marine air masses over the southern Baltic Sea. These chemical and physical processes include gas-to-particle conversion that led to an increase of Hg associated with coarse particles, which due to higher dry deposition rates, enhanced local scale deposition and limited the transport of this toxic trace metal. Daily (24 h) sampling of size-segregated atmospheric particles revealed the sea to be a sink for Hg during winter months and as a source of Hg during summer months. Poland is one of the major Hg emitters among the Baltic States according to International HELCOM Reports. Thus, important measurements in this region were conducted over a one-year period from December 18, 2007 to December 15, 2008. The range in concentrations of Hg in particulate matter (2-142 pg m -3) at the Polish site are comparable to other measurements at sites along the coastal areas of the Baltic Sea. Annual Hg(p) represents 1% of the total atmospheric Hg (Hg TOT) under unpolluted or background ambient conditions. A major source of atmospheric Hg in this area is the combustion of fossil fuels, especially coal burning used for home heating. This was clearly seen in the statistically higher mean concentration of 24 pg m -3 observed during the heating season compared to the 15 pg m -3 measured during the non-heating season. Construction activities e.g., cement manufacturing, gravel extraction, and waste incineration during the warm season strongly influenced Hg concentrations and led to an increase in Hg(p) on working days compared to weekend days.

  20. Incorporation of diazotrophic fixed N2 by mesozooplankton — Case studies in the southern Baltic Sea

    NASA Astrophysics Data System (ADS)

    Wannicke, Nicola; Korth, Frederike; Liskow, Iris; Voss, Maren

    2013-05-01

    During two simultaneous cruises in the Central Baltic Sea in July 2007 we applied a 15N tracer addition approach to assess the impact of cyanobacterial N2 fixation on mesozooplankton production in the Central Baltic Sea. We determined rates of diazotrophic 15N2 fixation, as well as uptake of diazotrophic derived 15N by mesozooplankton species. Diazotrophic 15N2 fixation rates were low representing pre-bloom situations. A first order estimate using a two source mixing model of natural δ15N-PON abundance revealed that diazotrophic fixed N contributed to 27 ± 8% to mesozooplankton biomass. Additionally, the application of stable isotope tracer showed that fixed 15N was detectable in the mesozooplankton fraction within 1 h after the onset of the incubation. On a daily basis, 5% up to 100% of newly fixed 15N and 14% of cyanobacteria standing stock were incorporated by mesozooplankton species in our experimental set-ups. By applying size fractionating experiments and the usage of different control treatments, we calculated that the majority of 15N transfer (67%) was mediated by the release of nitrogenous compounds and their channelling through the microbial loop towards the mesozooplankton community. Moreover, direct grazing on filamentous cyanobacteria accounted for 33% of gross 15N incorporation. Grazing in the experiments seemed to be largely influenced by cyanobacterial species dominating the community and by the abundance of Cladoceran species like Evadne. Overall, N2 fixing cyanobacteria are ecological more important as instantaneous sources of nitrogen for higher trophic levels of the Baltic Sea food web than previously assumed.

  1. Climate change induced decadal variations in hydrodynamic conditions in the Eastern Baltic Sea

    NASA Astrophysics Data System (ADS)

    Suursaar, U.; Kullas, T.

    2010-12-01

    Climate change manifests in the Baltic Sea region as increasing air and water temperatures, decrease in salinity and in shortening of the ice period. In addition, atmospheric westflow and storminess has intensified, which should also lead to changes in hydrodynamic regime of the sea. The objective of the paper is to study these changes in the practically tideless, fetch-limited nearshore region of West Estonia. The study is based on meteorological and sea level data from the Estonian weather and tide gauge stations, as well as on hydrodynamic modelling experiments with the shallow sea 2D model and wave hindcast for the period 1966-2008. Corrected with locally varying postglacial land uplift rates, the sea level rise according to the Estonian data was 1.5-2.7 mm/year over the period 1842-2009. Steeper than the lobal sea level rise, the rise in winter sea level, and particularly in annual maxima (3.5-11.2 mm/year), could be explained by the local sea level response to the changing regional wind climate. There are site-dependent changes in current patterns and upwelling occurrences. The significant wave heights exhibited some quasiperiodic cycles with the last high stage in 1980-95 and a slightly decreasing overall trend. As a result of northward shifts in cyclone trajectories, annual maximum waves have increased along the windward coasts of West Estonia, but decreased on the northern coast.

  2. Dissolved organic phosphorus in the Baltic Sea - temporal variability and utilization

    NASA Astrophysics Data System (ADS)

    Nausch, Günther; Nausch, Monika; Steinrücken, Pia; Balke, Jana; Woelk, Jana

    2014-05-01

    The temporal variability of dissolved organic phosphorus (DOP) concentrations in the Baltic Sea was investigated during three cruises in summer 2008, late winter/early spring 2009 and summer 2012 with focus on the central Baltic Sea. In summer 2008, characteristic cyanobacteria blooms occured in the Baltic Proper and DOP concentrations in the surface layer of 0.32 ± 0.05 µM have been estimated. In summer 2012, meteorological conditions did not favour intense cyanobacteria development and DOP concentrations were with 0.24 ± 0.04 µM lower on average. DOP degradation in autumn and winter resulted in lower concentrations of 0.21 ± 0.06 µM as can be seen in the winter cruise 2009. During the first two cruises also the spatial distribution of DOP in the surface layer between the Skagerrak and the northern Gulf of Bothnia could be measured. Highest summer concentrations of 0.32 ± 0.05 µM were found in the Baltic Proper, followed by the Gulf of Finland having on mean 0.25 ± 0.01 µM. DOP decreased down to 0.12 µM in the phosphorus limited Bay of Bothnia. Similar low concentrations were measured in the Skagerrak. The same spatial DOP pattern as in summer 2008 was observed in late winter/early spring 2009, but on lower concentration levels, except the Skagerrak and Kattegat were the spring bloom already has started. In addition, the bioavailable and refractory DOP fractions (B-DOP and R-DOP) were measured in time course experiments in 2008 and 2012, excluding C- and N- limitation. In summer 2008, the R-DOP constituted a higher proportion of DOP compared to B-DOP. A gradient has been observed from the northernmost station in the Bothnian Bay to the southern Baltic Proper. In the Bothnian Bay, only 0.01µM B-DOP could be detected, comprising 8% of DOP whereas B-DOP constituted a proportion of 25-29% in the Gotland Basin and up to 46% in the Gulf of Finland. In summer 2012, B-DOP concentrations of 0.09 ± 0.02 µM were measured in the eastern Gotland Basin

  3. Atmospheric pathways of chlorinated pesticides and natural bromoanisoles in the northern Baltic Sea and its catchment.

    PubMed

    Bidleman, Terry; Agosta, Kathleen; Andersson, Agneta; Brorström-Lundén, Eva; Haglund, Peter; Hansson, Katarina; Laudon, Hjalmar; Newton, Seth; Nygren, Olle; Ripszam, Matyas; Tysklind, Mats; Wiberg, Karin

    2015-06-01

    Long-range atmospheric transport is a major pathway for delivering persistent organic pollutants to the oceans. Atmospheric deposition and volatilization of chlorinated pesticides and algae-produced bromoanisoles (BAs) were estimated for Bothnian Bay, northern Baltic Sea, based on air and water concentrations measured in 2011-2012. Pesticide fluxes were estimated using monthly air and water temperatures and assuming 4 months ice cover when no exchange occurs. Fluxes were predicted to increase by about 50 % under a 2069-2099 prediction scenario of higher temperatures and no ice. Total atmospheric loadings to Bothnian Bay and its catchment were derived from air-sea gas exchange and "bulk" (precipitation + dry particle) deposition, resulting in net gains of 53 and 46 kg year(-1) for endosulfans and hexachlorocyclohexanes, respectively, and net loss of 10 kg year(-1) for chlordanes. Volatilization of BAs releases bromine to the atmosphere and may limit their residence time in Bothnian Bay. This initial study provides baseline information for future investigations of climate change on biogeochemical cycles in the northern Baltic Sea and its catchment. PMID:26022329

  4. Atmospheric pathways of chlorinated pesticides and natural bromoanisoles in the northern Baltic Sea and its catchment.

    PubMed

    Bidleman, Terry; Agosta, Kathleen; Andersson, Agneta; Brorström-Lundén, Eva; Haglund, Peter; Hansson, Katarina; Laudon, Hjalmar; Newton, Seth; Nygren, Olle; Ripszam, Matyas; Tysklind, Mats; Wiberg, Karin

    2015-06-01

    Long-range atmospheric transport is a major pathway for delivering persistent organic pollutants to the oceans. Atmospheric deposition and volatilization of chlorinated pesticides and algae-produced bromoanisoles (BAs) were estimated for Bothnian Bay, northern Baltic Sea, based on air and water concentrations measured in 2011-2012. Pesticide fluxes were estimated using monthly air and water temperatures and assuming 4 months ice cover when no exchange occurs. Fluxes were predicted to increase by about 50 % under a 2069-2099 prediction scenario of higher temperatures and no ice. Total atmospheric loadings to Bothnian Bay and its catchment were derived from air-sea gas exchange and "bulk" (precipitation + dry particle) deposition, resulting in net gains of 53 and 46 kg year(-1) for endosulfans and hexachlorocyclohexanes, respectively, and net loss of 10 kg year(-1) for chlordanes. Volatilization of BAs releases bromine to the atmosphere and may limit their residence time in Bothnian Bay. This initial study provides baseline information for future investigations of climate change on biogeochemical cycles in the northern Baltic Sea and its catchment.

  5. Biomarkers in the stratified water column of the Landsort Deep (Baltic Sea)

    NASA Astrophysics Data System (ADS)

    Berndmeyer, C.; Thiel, V.; Schmale, O.; Wasmund, N.; Blumenberg, M.

    2014-06-01

    The water column of the Landsort Deep, central Baltic Sea, is stratified into an oxic, suboxic and anoxic zone. This stratification controls the distributions of individual microbial communities and biogeochemical processes. In summer 2011, particulate organic matter was filtered from these zones using an in~situ pump. Lipid biomarkers were extracted from the filters to establish water column profiles of individual hydrocarbons, alcohols, phospholipid fatty acids, and bacteriohopanepolyols (BHPs). As a reference, a cyanobacterial bloom sampled in summer 2012 in the central Baltic Sea Gotland Deep was analyzed for BHPs. The biomarker data from the surface layer of the oxic zone showed major inputs from different cyanobacteria and eukaryotes such as dinoflagellates and ciliates, while the underlying cold winter water layer was characterized by a low diversity and abundance of organisms, with copepods as a major group. The suboxic zone supported bacterivorous ciliates, type I aerobic methanotrophic bacteria, sulfate reducing bacteria, and, most likely, methanogenic archaea. In the anoxic zone, sulfate reducers and archaea were the dominating microorganisms as indicated by the presence of distinctive branched fatty acids, archaeol and PMI derivatives, respectively. Our study of in situ biomarkers in the Landsort Deep thus provided an integrated insight into the distribution of relevant players and the related biogeochemical processes in stratified water columns of marginal seas.

  6. The influence of dissolved organic matter on the acid-base system of the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Kuliński, Karol; Schneider, Bernd; Hammer, Karoline; Machulik, Ulrike; Schulz-Bull, Detlef

    2014-04-01

    To assess the influence of dissolved organic matter (DOM) on the acid-base system of the Baltic Sea, 19 stations along the salinity gradient from Mecklenburg Bight to the Bothnian Bay were sampled in November 2011 for total alkalinity (AT), total inorganic carbon concentration (CT), partial pressure of CO2 (pCO2), and pH. Based on these data, an organic alkalinity contribution (Aorg) was determined, defined as the difference between measured AT and the inorganic alkalinity calculated from CT and pH and/or CT and pCO2. Aorg was in the range of 22-58 μmol kg- 1, corresponding to 1.5-3.5% of AT. The method to determine Aorg was validated in an experiment performed on DOM-enriched river water samples collected from the mouths of the Vistula and Oder Rivers in May 2012. The Aorg increase determined in that experiment correlated directly with the increased DOC concentration caused by enrichment of the > 1 kDa DOM fraction. To examine the effect of Aorg on calculations of the marine CO2 system, the pCO2 and pH values measured in Baltic Sea water were compared with calculated values that were based on the measured alkalinity and another variable of the CO2 system, but ignored the existence of Aorg. Large differences between measured and calculated pCO2 and pH were obtained when the computations were based on AT and CT. The calculated pCO2 was 27-56% lower than the measured value whereas the calculated pH was overestimated by more than 0.4 pH units. Since biogeochemical models are based on the transport and transformations of AT and CT, the acid-base properties of DOM should be included in calculations of the CO2 system in DOM-rich basins like the Baltic Sea. In view of our limited knowledge about the composition and acid/base properties of DOM, this is best achieved using a bulk dissociation constant, KDOM, that represents all weakly acidic functional groups present in DOM. Our preliminary results indicated that the bulk KDOM in the Baltic Sea is 2.94 · 10- 8 mol kg- 1

  7. Sulfidization of lacustrine glacial clay upon Holocene marine transgression (Arkona Basin, Baltic Sea)

    NASA Astrophysics Data System (ADS)

    Holmkvist, Lars; Kamyshny, Alexey; Brüchert, Volker; Ferdelman, Timothy G.; Jørgensen, Bo Barker

    2014-10-01

    Towards the end of the last deglaciation more than 13,500 years ago the southern Baltic Sea was a freshwater lake, the Baltic Ice Lake, for several thousand years during which iron-rich, organic-poor clay was deposited. The modern brackish-marine stage started about 8600 years ago with the deposition of organic-rich mud, which is today characterized by high rates of sulfate reduction and high concentrations of free sulfide. We studied the iron-sulfur diagenesis in gravity cores from the Arkona Basin, SW Baltic Sea, to track the progressing sulfidization front in the buried Ice Lake sediment. The geochemical zonation was unusual as the sulfate concentration dropped steeply by two thirds below which it increased again due to a deep sulfate reservoir. The reservoir had been established during the early Holocene marine period as sulfate and other seawater ions diffused down into the lake sediment for several thousand years. Sulfur isotope analyses confirmed its origin as seawater sulfate, while its oxygen isotope composition indicated a microbially catalyzed equilibration with ambient interstitial water, decoupled from net sulfate reduction. Today, hydrogen sulfide diffuses from the marine mud down into the lake sediment where a black band with high magnetic susceptibility and high iron monosulfide, greigite and elemental sulfur content shows progressing sulfidization of the large pool of solid-phase reactive iron. Dissolved iron from the deep Ice Lake sediment diffuses up to the sulfide front and provides a small supplement to the solid Fe(III) pool as a sulfide sink. Pyrite formation at the sulfidization front may involve surface-bound zero-valent sulfur while, above the front, polysulfides are in equilibrium with the system hydrogen sulfide - polysulfide - rhombic sulfur and may not be important for further pyrite formation. The Holocene iron-sulfur diagenesis observed in the Arkona Basin represents an important transitional state for post-glacial transgressions

  8. CO2 Storage Capacity of Saline Aquifers in the Swedish Sector of the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Sopher, Daniel; Juhlin, Christopher

    2014-05-01

    Carbon Capture and Storage (CCS) is one of a range of options to reduce CO2 emissions in order to mitigate climate change in the future. The Intra-cratonic Baltic Sea Basin contains several saline aquifers which could be suitable for CO2 storage. In this study the CO2 storage capacity of the Cambrian När and Faludden sandstone members is evaluated within the Swedish sector of the Baltic Sea Basin. A probabilistic approach is adopted to characterise both the most likely storage capacity estimate as well as the associated uncertainty. The storage capacity within structural closures and stratigraphic traps is considered. Depth structure maps generated using a dense grid of vintage 2D marine seismic data are used to assess the storage potential in structural traps for both potential reservoirs. A regional scale stratigraphic trap is also considered for the Faludden reservoir. Key input properties for the CO2 storage capacity calculations such as porosity, CO2 density and storage efficiency factor are characterised based on available well log and core data. CO2 storage capacities for the structural and stratigraphic traps are then calculated using a Monte Carlo type approach where the input parameters are randomly perturbed within a set range. A statistical analysis of the input parameters is used to define the range within which these properties are allowed to vary, both spatially and at a given point. Finally these results are compared to others for the greater Baltic Sea region. This approach allows a most likely CO2 storage capacity estimate as well as low and high estimates to be obtained for the Swedish sector of the Baltic Sea in the investigated formations. Based on these results it appears that the largest storage capacity lies within the regional stratigraphic trap of the Faludden reservoir. The structural traps provide significantly smaller volumes when compared to the Faludden stratigraphic trap. The majority of the structural traps are also less certain

  9. Structures and Activity of New Anabaenopeptins Produced by Baltic Sea Cyanobacteria.

    PubMed

    Spoof, Lisa; Błaszczyk, Agata; Meriluoto, Jussi; Cegłowska, Marta; Mazur-Marzec, Hanna

    2015-12-30

    Anabaenopeptins, bioactive cyclic hexapeptides, were isolated by preparative reversed-phase high performance liquid chromatography from an extract of Baltic Sea cyanobacterial bloom material composed of Nodularia spumigena (50%), Aphanizomenon flos-aquae (40%) and Dolichospermum spp. (10%). Five new anabaenopeptins and nine previously known anabaenopeptins were isolated, and their putative structures were determined by tandem mass spectrometry. The activity of the peptides against carboxypeptidase A and protein phosphatase 1 as well as chymotrypsin, trypsin and thrombin was tested. All anabaenopeptins inhibited carboxypeptidase A (apart from one anabaenopeptin variant) and protein phosphatase 1 with varying potency, but no inhibition against chymotrypsin, trypsin and thrombin was observed.

  10. Vertical distribution of (241)Pu in the southern Baltic Sea sediments.

    PubMed

    Strumińska-Parulska, Dagmara I

    2014-12-15

    The vertical distribution of plutonium (241)Pu in marine sediments can assist in determining the deposition history and sedimentation process of analyzed regions. In addition, (241)Pu/(239+240)Pu activity ratio could be used as a sensitive fingerprint for radioactive source identification. The present preliminary studies on vertical distribution of (241)Pu in sediments from four regions of the southern Baltic Sea are presented. The distribution of (241)Pu was not uniform and depended on sediment geomorphology and depth as well as location. The highest concentrations of plutonium were found in the surface layers of all analyzed sediments and originated from the Chernobyl accident. PMID:25455816

  11. Structures and Activity of New Anabaenopeptins Produced by Baltic Sea Cyanobacteria

    PubMed Central

    Spoof, Lisa; Błaszczyk, Agata; Meriluoto, Jussi; Cegłowska, Marta; Mazur-Marzec, Hanna

    2015-01-01

    Anabaenopeptins, bioactive cyclic hexapeptides, were isolated by preparative reversed-phase high performance liquid chromatography from an extract of Baltic Sea cyanobacterial bloom material composed of Nodularia spumigena (50%), Aphanizomenon flos-aquae (40%) and Dolichospermum spp. (10%). Five new anabaenopeptins and nine previously known anabaenopeptins were isolated, and their putative structures were determined by tandem mass spectrometry. The activity of the peptides against carboxypeptidase A and protein phosphatase 1 as well as chymotrypsin, trypsin and thrombin was tested. All anabaenopeptins inhibited carboxypeptidase A (apart from one anabaenopeptin variant) and protein phosphatase 1 with varying potency, but no inhibition against chymotrypsin, trypsin and thrombin was observed. PMID:26729139

  12. Phosphorus recycling and burial in Baltic Sea sediments with contrasting redox conditions

    NASA Astrophysics Data System (ADS)

    Slomp, Caroline P.; Mort, Haydon P.; Reed, Dan C.; Jilbert, Tom; Gustafsson, Bo G.

    2010-05-01

    The Baltic Sea is a classical example of a coastal system that is subject to an increased intensity and spatial extent of hypoxia due to human activities. The expansion of hypoxia since the 1960s is the result of increased inputs of nutrients from land (both from fertilizer and wastewater) and is negatively affecting living conditions for benthic organisms. In addition, the biogeochemical cycling of carbon and nutrients has been significantly altered. Water column studies have shown that the availability of dissolved inorganic phosphorus (DIP) is positively correlated with hypoxia due to release of phosphorus from sediment Fe-oxides and from organic matter upon the transition from oxic to hypoxic conditions. Thus, a large internal source of phosphorus exists in the sediment that largely controls short-term variability in water column DIP concentrations. In this presentation, we focus on results of recent field and modeling work for various parts of the Baltic Sea that confirm the role of Fe-bound P from seasonally hypoxic sediments at intermediate water depths as a major source of DIP. We also show that extended hypoxia and anoxia leads to depletion of sediment Fe-bound P and, ultimately, lower rates of sediment-water exchange of P. Authigenic Ca-P minerals appear to be only a relatively minor burial sink for P. The lack of major inorganic P burial makes the Baltic Sea sensitive to the feedback loop between increased hypoxia, enhanced regeneration of P and increased primary productivity. Historical records of bottom water oxygen at two sites (Bornholm, Northern Gotland) show a decline over the past century which is accompanied by a rise in values of typical sediment proxies for anoxia (total sulfur, molybdenum and organic C/P ratios). While sediment reactive P concentrations in anoxic basins are equal to or higher than at oxic sites, burial rates of P at hypoxic and anoxic sites are up to 20 times lower because of lower sedimentation rates. Nevertheless, burial of

  13. Vertical distribution of (241)Pu in the southern Baltic Sea sediments.

    PubMed

    Strumińska-Parulska, Dagmara I

    2014-12-15

    The vertical distribution of plutonium (241)Pu in marine sediments can assist in determining the deposition history and sedimentation process of analyzed regions. In addition, (241)Pu/(239+240)Pu activity ratio could be used as a sensitive fingerprint for radioactive source identification. The present preliminary studies on vertical distribution of (241)Pu in sediments from four regions of the southern Baltic Sea are presented. The distribution of (241)Pu was not uniform and depended on sediment geomorphology and depth as well as location. The highest concentrations of plutonium were found in the surface layers of all analyzed sediments and originated from the Chernobyl accident.

  14. Bacteriohopanepolyols record stratification, nitrogen fixation and other biogeochemical perturbations in Holocene sediments of the Central Baltic Sea

    NASA Astrophysics Data System (ADS)

    Blumenberg, M.; Berndmeyer, C.; Moros, M.; Muschalla, M.; Schmale, O.; Thiel, V.

    2012-12-01

    The Baltic Sea, one of the world's largest brackish-marine basins, established after deglaciation of Scandinavia about 17 000 to 15 000 yr ago. In the changeable history of the Baltic Sea, the initial freshwater system was connected to the North Sea about 8000 yr ago and the modern brackish-marine setting (Littorina Sea) was established. Today, a relatively stable stratification developed in the water column of the deep basins due to salinity differences. Stratification is only occasionally interrupted by mixing events, and controls nutrient availability and growth of specifically adapted microorganisms and algae. We studied bacteriohopanepolyols (BHPs), lipids of specific bacterial groups, in a sediment core from the Central Baltic Sea (Gotland Deep) and found considerable differences between the distinct stages of the Baltic Sea's history. Individual BHP structures indicate contributions from as yet unknown redoxcline-specific bacteria (bacteriohopanetetrol isomer), methanotrophic bacteria (35-aminobacteriohopanetetrol), cyanobacteria (bacteriohopanetetrol cyclitol ether isomer) and, through allochthonous input after the Littorina transgression, from soil bacteria (adenosylhopane), whereas the origin of other BHPs in the core has still to be identified. Notably high BHP abundances were observed in the deposits of the brackish-marine Littorina phase, particularly in laminated sediment layers. Because these sediments record periods of stable water column stratification, bacteria specifically adapted to these conditions may account for the high portions of BHPs. An additional and/or accompanying source may be nitrogen-fixing (cyano)bacteria, which is indicated by a good correlation of BHP abundances with Corg and δ15N.

  15. Spatial variation of statistical properties of extreme water levels along the eastern Baltic Sea

    NASA Astrophysics Data System (ADS)

    Pindsoo, Katri; Soomere, Tarmo; Rocha, Eugénio

    2016-04-01

    Most of existing projections of future extreme water levels rely on the use of classic generalised extreme value distributions. The choice to use a particular distribution is often made based on the absolute value of the shape parameter of the Generalise Extreme Value distribution. If this parameter is small, the Gumbel distribution is most appropriate while in the opposite case the Weibull or Frechet distribution could be used. We demonstrate that the alongshore variation in the statistical properties of numerically simulated high water levels along the eastern coast of the Baltic Sea is so large that the use of a single distribution for projections of extreme water levels is highly questionable. The analysis is based on two simulated data sets produced in the Swedish Meteorological and Hydrological Institute. The output of the Rossby Centre Ocean model is sampled with a resolution of 6 h and the output of the circulation model NEMO with a resolution of 1 h. As the maxima of water levels of subsequent years may be correlated in the Baltic Sea, we also employ maxima for stormy seasons. We provide a detailed analysis of spatial variation of the parameters of the family of extreme value distributions along an approximately 600 km long coastal section from the north-western shore of Latvia in the Baltic Proper until the eastern Gulf of Finland. The parameters are evaluated using maximum likelihood method and method of moments. The analysis also covers the entire Gulf of Riga. The core parameter of this family of distributions, the shape parameter of the Generalised Extreme Value distribution, exhibits extensive variation in the study area. Its values evaluated using the Hydrognomon software and maximum likelihood method, vary from about -0.1 near the north-western coast of Latvia in the Baltic Proper up to about 0.05 in the eastern Gulf of Finland. This parameter is very close to zero near Tallinn in the western Gulf of Finland. Thus, it is natural that the Gumbel

  16. Genetic diversity of Saccharina latissima (Phaeophyceae) along a salinity gradient in the North Sea-Baltic Sea transition zone.

    PubMed

    Møller Nielsen, Mette; Paulino, Cristina; Neiva, João; Krause-Jensen, Dorte; Bruhn, Annette; Serrão, Ester A

    2016-08-01

    The North Sea-Baltic Sea transition zone constitutes a boundary area for the kelp species Saccharina latissima due to a strong salinity gradient operating in the area. Furthermore, the existence of S. latissima there, along Danish waters, is fairly patchy as hard bottom is scarce. In this study, patterns of genetic diversity of S. latissima populations were evaluated along the salinity gradient area of Danish waters (here designated brackish) and were compared to reference sites (here designated marine) outside the gradient area, using microsatellite markers. The results showed that the S. latissima populations were structured into two clusters corresponding to brackish versus marine sites, and that gene flow was reduced both between clusters and between populations within clusters. In addition, results provided empirical evidence that marginal populations of S. latissima in the salinity gradient area exhibited a distinct genetic structure when compared to marine ones. Brackish populations were less diverse, more related, and showed increased differentiation over distance compared to marine populations. The isolation of the brackish S. latissima populations within the salinity gradient area of Danish waters in conjunction with their general low genetic diversity makes these populations vulnerable to ongoing environmental and climate change, predicted to result in declining salinity in the Baltic Sea area that may alter the future distribution and performance of S. latissima in the area. PMID:27151230

  17. Sediment trace metals as a recorder of bottom water redox conditions in the Baltic Sea over the Holocene

    NASA Astrophysics Data System (ADS)

    Slomp, C. P.; Jilbert, T.; van Riel, K. P. G. L.; Mort, H. P.; Conley, D. J.; Gustafsson, B. G.

    2012-04-01

    Increased inputs of nutrients from waste water and fertilizer have driven enhanced algal growth in the surface waters of the Baltic Sea over the past century. The sinking of this organic matter to the seafloor and subsequent decay has led to an oxygen demand in the bottom water that outpaces oxygen supply. Water column records indicate that this has resulted in a major redox shift in bottom water conditions from oxic to sulfidic (euxinic) in the late 1970's and early 1980's. Here, we show that this redox shift is recorded in sediment trace metal records throughout the Baltic Proper. We demonstrate that while rhenium (Re) tracks suboxia, molybdenum (Mo) is an accurate indicator of euxinia in the Baltic Sea. We subsequently use sediment Mo data for two long cores to assess changes in redox conditions over the Holocene. At one site, our results confirm earlier work showing three distinct periods of bottom water euxinia, namely during modern and medieval times and the early Holocene. The second site, in contrast, was euxinic throughout most of the Holocene. We suggest that the variable trends in redox observed at the first site are representative for most of the Baltic Proper and long-term bottom water euxinia in the Baltic Sea is limited to several small restricted basins.

  18. GIS analysis of effects of future Baltic sea level rise on the island of Gotland, Sweden

    NASA Astrophysics Data System (ADS)

    Ebert, Karin; Ekstedt, Karin; Jarsjö, Jerker

    2016-07-01

    Future sea level rise as a consequence of global warming will affect the world's coastal regions. Even though the pace of sea level rise is not clear, the consequences will be severe and global. Commonly the effects of future sea level rise are investigated for relatively vulnerable development countries; however, a whole range of varying regions needs to be considered in order to improve the understanding of global consequences. In this paper we investigate consequences of future sea level rise along the coast of the Baltic Sea island of Gotland, Sweden, with the aim to fill knowledge gaps regarding comparatively well-suited areas in developed countries. We study both the quantity of the loss of features of infrastructure, cultural, and natural value in the case of a 2 m sea level rise of the Baltic Sea and the effects of climate change on seawater intrusion in coastal aquifers, which indirectly cause saltwater intrusion in wells. We conduct a multi-criteria risk analysis by using lidar data on land elevation and GIS-vulnerability mapping, which gives the application of distance and elevation parameters formerly unimaginable precision. We find that in case of a 2 m sea level rise, 3 % of the land area of Gotland, corresponding to 99 km2, will be inundated. The features most strongly affected are items of touristic or nature value, including camping places, shore meadows, sea stack areas, and endangered plants and species habitats. In total, 231 out of 7354 wells will be directly inundated, and the number of wells in the high-risk zone for saltwater intrusion in wells will increase considerably. Some valuable features will be irreversibly lost due to, for example, inundation of sea stacks and the passing of tipping points for seawater intrusion into coastal aquifers; others might simply be moved further inland, but this requires considerable economic means and prioritization. With nature tourism being one of the main income sources of Gotland, monitoring and

  19. Overview of key phytoplankton toxins and their recent occurrence in the North and Baltic Seas.

    PubMed

    Luckas, B; Dahlmann, J; Erler, K; Gerdts, G; Wasmund, N; Hummert, C; Hansen, P D

    2005-02-01

    The frequency and intensity of harmful algal blooms (HABs) appear to be on the rise globally. There is also evidence of the geographic spreading of toxic strains of these algae. Consequently, methods had to be established and new ones are still needed for the evaluation of possible hazards caused by increased algal toxin production in the marine food chain. Different clinical effects of algae-related poisoning have attracted scientific attention; paralytic shellfish poisoning, diarrhetic shellfish poisoning, and amnesic shellfish poisoning are among the most common. Additionally, cyanobacteria (blue-green algae) in brackish waters often produce neurotoxic and hepatotoxic substances. Bioassays with mice or rats are common methods to determine algal and cyanobacterial toxins. However, biological tests are not really satisfactory because of their low sensitivity. In addition, there is growing public opposition to animal testing. Therefore, there has been increasing effort to determine algal toxins by chemical methods. Plankton samples from different European marine and brackish waters were taken during research cruises and analyzed on board directly. The ship routes covered marine areas in the northwest Atlantic, Orkney Islands, east coast of Scotland, and the North and Baltic seas. The first results on the occurrence and frequency of harmful algal species were obtained in 1997 and 1998. During the 2000 cruise an HPLC/MS coupling was established on board, and algal toxins were measured directly after extraction of the plankton samples. In contrast to earlier cruises, the sampling areas were changed in 2000 to focusing on coastal zones. The occurrence of toxic algae in these areas was compared to toxin formation during HABs in the open sea. It was found that the toxicity of the algal blooms depended on the prevailing local conditions. This observation was also confirmed by monitoring cyanobacterial blooms in the Baltic Sea. Optimal weather conditions, for example

  20. Concentrations of halogenated natural products versus PCB 153 in bivalves from the North and Baltic Seas.

    PubMed

    Hauler, Carolin; Rimkus, Gerhard; Risacher, Célia; Knölker, Hans-Joachim; Vetter, Walter

    2014-08-15

    Different halogenated natural products (HNPs) have been reported to occur in marine wildlife, particularly from regions with comparably little contamination with anthropogenic pollutants. The North Sea and the Baltic Sea have been known as a marine site heavily polluted with organohalogen compounds, and especially with polychlorinated biphenyls (PCBs). In this study we wished to determine the current abundance of HNPs in comparison with 2,2',4,4',5,5'-hexachlorobiphenyl (PCB 153), i.e. the major PCB congener in marine biota. For this purpose, forty blue mussels (Mytilus edulis) and oysters (Crassostrea gigas) from seven sites were analyzed on HNPs and PCB 153. Most of the samples contained HNPs in the form of polyhalogenated 1'-methyl-1,2'-bipyrroles (PMBPs including Q1) and the mixed halogenated compound MHC-1. In addition we determined several polyhalogenated 1,1'-dimethyl-2,2'-bipyrroles (PDBPs), 2,3,4,5-tetrabromo-N-methylpyrrole and several novel homologs, as well as polybrominated N-methylindoles. The occurrence of these HNP groups were considerably different in the samples from different regions with varying sum concentrations up to 1930 μg/kg lipids in blue mussels from Heligoland (North Sea) and much lower concentrations in samples from the Baltic Sea (up to 13 μg/kg lipids). The concentrations of HNPs varied by two orders of magnitude, compared to a factor of 10 for PCB 153, suggesting that HNPs are more spatially (and perhaps temporally) variant than POPs. In the North Sea region Heligoland, HNPs were more abundant than PCB 153.

  1. Fishing cod in the Baltic Sea - Gambling with the ecosystem services

    NASA Astrophysics Data System (ADS)

    Björkman, Sven; Nordlöf, Anders

    2014-05-01

    The population of cod in the Baltic sea has over the last decades decreased due to overfishing. To make the students aware of this problem and also to find a solution they are introduced to a game. The purpose of the game is to let the students know how to use renewable natural resources in these aspects; 1 Fishing cod without using it up 2 That solidarity is needed if you are sharing a resource 3 That cooperation is the key to keeping a natural resource healthy. The students are fishermen in group of four and are equipped with a boat. The playing board is a map over the Baltic sea. The rules of the game include the carrying capacity of the sea, how much fish one fishing boat is allowed to pick up, how much it costs to have a boat, and possibilities to buy a bigger boat. The game has two rounds: In round one the students in the group are competing against each other, they are not allowed to talk to each other and they are supposed to get as much fish as they can. As a consequence after round one the sea will become empty. In round two the groups compete with each other and they are coworking within the group. After this round the result is different from the first round. The catches are bigger than in round one and still there are cod left in the sea, which will generate a good fishing in the future.. The discussions after the game can be about why the two rounds ended so different, general discussion about "tragedy of the commons", sustainable use of ecosystem services and discussions about resources in common.

  2. Understanding salt dynamics for a restored coastal wetland at the Baltic Sea in Germany

    NASA Astrophysics Data System (ADS)

    Selle, Benny; Gräff, Thomas; Salzmann, Thomas; Oswald, Sascha; Walther, Marc; Miegel, Konrad

    2016-04-01

    Coastal fens like the nature reserve „Hütelmoor und Heiligensee"(north-eastern Germany) are important landscape elements along the southern Baltic coast, which exchange fresh water and brackish water with the Baltic Sea. These exchange processes can be understood as experiments with a natural tracer, which may be used to investigate the hydrologic behaviour of these fen systems. With the establishment of coastal protection measures such as dunes and dikes, the installation of surface drainage and, more recently, also nature conservation measures, the hydrologic regime of these coastal wetlands constantly altered over the last centuries. The rehabilitated wetland „Hütelmoor und Heiligensee" is suitable for an analysis of hydrologic change as it was monitored over the time period since nature conservation measures started in the 1990s. Collected data sets include observation of groundwater levels and electrical conductivities, weather data as well as discharge at the outlet of the drainage catchment. In this study, we identifed processes and quantify process magnitudes that govern the salt balance of the study area including its variability in space and time. We found that - over the period of rehabilitation - salt water entered the catchment with episodic storm surges by wave overtopping of dunes. The intruded brackish water was then diluted, which is a slow process occurring over decades. It is governed by local groundwater recharge from precipitation and the inflow of relatively fresh groundwater from the hinterland. It is concluded that salt inputs from the Baltic Sea provide a natural tracer of hydrological processes, which can be readily monitored via electrical conductivity measurements.

  3. Lipid-soluble conjugates of hydroxylated polybrominated diphenyl ethers in blue mussels from the Baltic Sea.

    PubMed

    Lindqvist, Dennis; Jensen, Sören; Asplund, Lillemor

    2014-01-01

    Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) of proposed natural origin have been detected throughout the food web of the Baltic Sea. Some OH-PBDEs have been shown to disrupt oxidative phosphorylation and the thyroid hormone system in exposed organisms. This paper describes an investigation into the fate of OH-PBDEs in the Baltic Sea's predominant specie, the blue mussel. The main focus was on the conjugation of OH-PBDEs with lipophilic moieties (e.g., fatty acids) and the potential role this transformation mechanism may have in heavily exposed mussels in nature. Analytical methods were developed to accurately determine the concentrations of these conjugates in blue mussels collected on different occasions during the summer in a coastal area of the Baltic proper. The measured concentrations of conjugated OH-PBDEs were compared to those of the unconjugated parent compounds, and it was found that in some cases, the levels of the conjugated derivatives can be equal or even higher than the levels of the unconjugated OH-PBDEs. This is, to our knowledge, the first study on lipid-soluble OH-PBDE conjugates, and the first study to investigate the occurrence of such conjugates of halogenated phenolic compounds in environmentally exposed mussels. The mussels were also found to contain hydrolysable water-soluble derivatives of OH-PBDEs (such as e.g., glucuronic acid and/or sulfate conjugates etc.). These were tentatively determined to be of lower concentration (by up to an order of magnitude) than that of the OH-PBDEs which were conjugated with lipophilic moieties.

  4. A Eulerian nutrient to fish model of the Baltic Sea — A feasibility-study

    NASA Astrophysics Data System (ADS)

    Radtke, Hagen; Neumann, Thomas; Fennel, Wolfgang

    2013-09-01

    A nutrient-to-fish-model with an explicit two-way interaction between a biogeochemical model of the lower food web and a fish model component is presented for the example of the Baltic Sea, demonstrating the feasibility of a consistent coupling of the upper and lower parts of the food web in a Eulerian model system. In the Baltic Sea, the fish stock is dominated by two prey species (sprat and herring) and one predator (cod). The dynamics of the fish model is driven by size (mass-class) dependent predator-prey interactions while the interaction between the biogeochemical and Fish model component is established through feeding of prey fish on zooplankton and recycling of fish biomass to nutrients and detritus. The fish model component is coupled to an advanced three dimensional biogeochemical model (ERGOM, Neumann et al., 2002). A horizontally explicit representation of fish requires the implementation of fish behavior. As a first step, we propose an algorithm to stimulate fish migration by letting the fish follow the food. Moreover, fish species are guided to their respective spawning areas. Results of first three-dimensional simulations are presented with emphasis on the transport of matter by moving fish. The spawning areas of cod and sprat are in the deep basins, which are not well reached by advective transport. Hence the deposition of matter in these areas by spawning fish could play some role in the distribution of matter. The approach is not limited to applications for the Baltic and the model can be transferred also to other systems.

  5. Seasonal variations of hydroxylated and methoxylated brominated diphenyl ethers in blue mussels from the Baltic Sea.

    PubMed

    Löfstrand, Karin; Liu, Xitao; Lindqvist, Dennis; Jensen, Sören; Asplund, Lillemor

    2011-07-01

    Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) and methoxylated polybrominated diphenyl ethers (MeO-PBDEs) found at high levels in the Baltic biota are mainly natural products, but can also be formed through metabolism or abiotic oxidation of polybrominated diphenyl ethers (PBDEs). The formation of OH-PBDEs is of concern since there is growing evidence of phenolic toxicity. This study investigates seasonal variations in levels of OH-PBDEs and MeO-PBDEs, focusing on an exposed species, the blue mussel (Mytilus edulis), sampled in the Baltic Sea in May, June, August and October of 2008. Both the OH-PBDE and MeO-PBDE levels in the mussels showed seasonal variations from May to October, the highest concentration of each congener appearing in June. The seasonal variation was more marked for OH-PBDEs than in MeO-PBDEs, but all congeners showed the same trends, except 6-MeO-BDE47 and 2'-MeO-BDE68, which did not significantly decline in concentrations after June. Biotic or abiotic debromination is suggested as a possible reason for the rapid decrease in methoxylated penta- and hexa-BDE concentrations observed in blue mussels from June to August, while the tetraBDE concentrations were stable. In addition, 1,3,7/1,3,8-tribrominated dibenzo-p-dioxins showed the same seasonal variation. The seasonal variations indicates natural formation and are unlikely to be due to transformation of anthropogenic precursors. The levels of PBDEs were fairly constant over time and considerably lower than those of the OH-PBDEs and MeO-PBDEs. The timing of the peaks in concentrations suggests that filamentous macro-algae may be important sources of these compounds found in the blue mussels from this Baltic Sea location.

  6. Equilibrium passive sampling as a tool to study polycyclic aromatic hydrocarbons in Baltic Sea sediment pore-water systems.

    PubMed

    Lang, Susann-Cathrin; Hursthouse, Andrew; Mayer, Philipp; Kötke, Danjiela; Hand, Ines; Schulz-Bull, Detlef; Witt, Gesine

    2015-12-15

    Solid Phase Microextraction (SPME) was applied to provide the first large scale dataset of freely dissolved concentrations for 9 polycyclic aromatic hydrocarbons (PAHs) in Baltic Sea sediment cores. Polydimethylsiloxane (PDMS) coated glass fibers were used for ex-situ equilibrium sampling followed by automated thermal desorption and GC-MS analysis. From the PAH concentrations in the fiber coating we examined (i) spatially resolved freely dissolved PAH concentrations (Cfree); (ii) baseline toxicity potential on the basis of chemical activities (a); (iii) site specific mixture compositions; (iv) diffusion gradients at the sediment water interface and within the sediment cores and (v) site specific distribution ratios. Contamination levels were low in the northern Baltic Sea, moderate to elevated in the Baltic Proper and highest in the Gulf of Finland. Chemical activities were well below levels expected to cause narcosis to benthos organisms. The SPME method is a very sensitive tool that opens new possibilities for studying the PAHs at trace levels in marine environments.

  7. Atmospheric nutrient input to the Baltic sea from 1850 to 2006: a reconstruction from modeling results and historical data.

    PubMed

    Ruoho-Airola, Tuija; Eilola, Kari; Savchuk, Oleg P; Parviainen, Maija; Tarvainen, Virpi

    2012-09-01

    In this study, a consistent basin-wise monthly time series of the atmospheric nutrient load to the Baltic Sea during 1850-2006 was compiled. Due to the lack of a long time series (1850-1960) of nutrient deposition to the Baltic Sea, the data set was compiled by combining a time series of deposition data at the Baltic Nest Institute from 1970 to 2006, published historical monitoring data and deposition estimates, as well as recent modeled Representative Concentration Pathways (RCP) emission estimates. The procedure for nitrogen compounds included estimation of the deposition in a few intermediate reference years, linear interpolation between them, and the decomposition of annual deposition into a seasonal deposition pattern. As no reliable monitoring results were found for the atmospheric deposition of phosphorus during the early period of our study, we used published estimates for the temporal and spatial pattern of the phosphorus load.

  8. Atmospheric nutrient input to the Baltic sea from 1850 to 2006: a reconstruction from modeling results and historical data.

    PubMed

    Ruoho-Airola, Tuija; Eilola, Kari; Savchuk, Oleg P; Parviainen, Maija; Tarvainen, Virpi

    2012-09-01

    In this study, a consistent basin-wise monthly time series of the atmospheric nutrient load to the Baltic Sea during 1850-2006 was compiled. Due to the lack of a long time series (1850-1960) of nutrient deposition to the Baltic Sea, the data set was compiled by combining a time series of deposition data at the Baltic Nest Institute from 1970 to 2006, published historical monitoring data and deposition estimates, as well as recent modeled Representative Concentration Pathways (RCP) emission estimates. The procedure for nitrogen compounds included estimation of the deposition in a few intermediate reference years, linear interpolation between them, and the decomposition of annual deposition into a seasonal deposition pattern. As no reliable monitoring results were found for the atmospheric deposition of phosphorus during the early period of our study, we used published estimates for the temporal and spatial pattern of the phosphorus load. PMID:22926878

  9. Determination of /sup 239,240/Pu in bottom sediments of the Baltic Sea

    SciTech Connect

    Kuznetsov, Yu.V.; Legin, V.K.; Pospelov, Yu.N.; Simonyak, Z.N.

    1988-11-01

    We present a technique for determining the /sup 239,240/Pu content, using /sup 236/Pu as the monitor of chemical yield, in samples of soils and bottom sediments - objects of the external environment. Plutonium is extracted from the matrix material by leaching with a mixture of concentrated acids HCl-HNO/sub 3/, after which it is separated by ion-exchange methods. After electrodeposition onto stainless steel discs the activity of the nuclides of plutonium is measured by the method of alpha-spectrometry. The average chemical yields during the analysis of the samples was 40-60%, the relative standard deviation was 10%, and the lower limit of detectability was 0.3 Bq. We present results of the determination of the /sup 239,240/Pu content in surface samples of bottom sediments from the Gulf of Finland and that past of the Baltic Sea which adjoins the territory of the USSR. It is found that the unit activity of /sup 239,240/Pu in the bottom sediments varies within the limits of 0.4-1.2 Bq/kg and lies at the global level. Global genesis of /sup 239,240/Pu in the bottom sediments of the Gulf of Finland and the open parts of the Baltic Sea is also confirmed by the values which are found for the ratios /sup 238/Pu//sup 239,240/Pu and /sup 239,240/Pu//sup 137/Cs.

  10. Biomass and number of fish impinged at a nuclear power plant by the Baltic Sea.

    PubMed

    Bryhn, Andreas C; Bergenius, Mikaela A J; Dimberg, Peter H; Adill, Anders

    2013-12-01

    The main aim of this study was to investigate the number and biomass of impinged fish at Forsmark Nuclear Power Plant in Sweden, located on the coast of the Baltic Sea. Of particular interest was the number of impinged individuals of the critically endangered European eel (Anguilla anguilla) which is regularly caught in the cooling system. Another aim was to determine the comparability of the results from Forsmark and results from impingement studies in other types of waters. Cross-systems studies make it possible to (1) estimate fish loss at plants where fish is not counted, and (2) to predict changes in fish loss from changes in electricity production or cooling water use. In 2010, 31,300,000 fish with a total biomass of 62,600 kg were impinged at Forsmark. In 2011, 27,300,000 fish weighing 38,500 kg were impinged. The maximum peak in total fish number and biomass occurred in spring. The most critical period for herring was in late summer and early autumn. Regarding eel, the largest impingement losses were recorded in November. The number of fish agreed with earlier established quantities of impinged fish in both freshwater and marine ecosystems. The study also estimated that 1,300 critically endangered eels could survive at Forsmark each year if a fish return system would be constructed to allow the passage of fish from the plant back to the Baltic Sea. PMID:23880915

  11. Biomarkers in the stratified water column of the Landsort Deep (Baltic Sea)

    NASA Astrophysics Data System (ADS)

    Berndmeyer, C.; Thiel, V.; Schmale, O.; Wasmund, N.; Blumenberg, M.

    2014-12-01

    The water column of the Landsort Deep, central Baltic Sea, is stratified into an oxic, suboxic, and anoxic zone. This stratification controls the distributions of individual microbial communities and biogeochemical processes. In summer 2011, particulate organic matter was filtered from these zones using an in situ pump. Lipid biomarkers were extracted from the filters to establish water-column profiles of individual hydrocarbons, alcohols, phospholipid fatty acids, and bacteriohopanepolyols (BHPs). As a reference, a cyanobacterial bloom sampled in summer 2012 in the central Baltic Sea Gotland Deep was analyzed for BHPs. The biomarker data from the surface layer of the oxic zone showed major inputs from cyanobacteria, dinoflagellates, and ciliates, while the underlying cold winter water layer was characterized by a low diversity and abundance of organisms, with copepods as a major group. The suboxic zone supported bacterivorous ciliates, type I aerobic methanotrophic bacteria, sulfate-reducing bacteria, and, most likely, methanogenic archaea. In the anoxic zone, sulfate reducers and archaea were the dominating microorganisms as indicated by the presence of distinctive branched fatty acids: archaeol and pentamethylicosane (PMI) derivatives, respectively. Our study of in situ biomarkers in the Landsort Deep thus provided an integrated insight into the distribution of relevant compounds and describes useful tracers to reconstruct stratified water columns in the geological record.

  12. Arsenic concentrations in Baltic Sea sediments close to chemical munitions dumpsites

    NASA Astrophysics Data System (ADS)

    Bełdowski, Jacek; Szubska, Marta; Emelyanov, Emelyan; Garnaga, Galina; Drzewińska, Anna; Bełdowska, Magdalena; Vanninen, Paula; Östin, Anders; Fabisiak, Jacek

    2016-06-01

    In addition to natural sources and land-originated pollution, the Baltic Sea has another anthropogenic source of arsenic in bottom sediments-arsenic-based Chemical Warfare Agents (CWA). To examine the potential usage of arsenic contents results for monitoring the leakage from chemical weapons, sediment samples were collected from officially reported and potential chemical weapon dumpsites located in the Baltic Sea, and total and inorganic arsenic concentrations were analyzed. Results showed an elevated arsenic content in dumpsite areas compared to reference areas. Correlations of arsenic with other metals and organic matter were studied to elucidate any unusual behavior of arsenic in the dumpsites. In the area of the Bornholm Deep, such behavior was observed for inorganic arsenic. It appears that in close vicinity of dumped munitions, the inorganic arsenic concentration of sediments is not correlated with either organic matter content or authigenic minerals formation, as is commonly observed elsewhere. Investigations on CWA concentrations, performed within the CHEMSEA (Chemical Munition Search and Assesment) project, allowed us to compare the results of arsenic concentrations with the occurrence of arsenic-containing CWA.

  13. Immunosuppression in harbour seals fed fish from the contaminated Baltic Sea

    SciTech Connect

    Ross, P.S. |; Swart, R.L. de |; Timmerman, H.H.; Loveren, H. van; Vos, J.G.; Vedder, L.J.; Reijnders, P.J.H.; Osterhaus, A.D.M.E.

    1994-12-31

    Environmental contaminants including dioxins and polychlorinated biphenyls have been shown to be immunotoxic in laboratory animals, but little information exists as to their possible effect on mammals in the natural environment. Recent virus-induced mass mortalities among marine mammals occupying high trophic levels have led to much speculation regarding a possible contributory role of pollutants in these events. The authors undertook a two-year captive feeding experiment with harbor seals, Phoca vitulina, where one group was fed herring from the contaminated Baltic Sea and a second group was fed relatively uncontaminated herring from the Atlantic Ocean. During the course of the experiment, they regularly sampled blood and undertook a series of immune function tests. They observed a significant impairment of natural killer cell activity and T-lymphocyte function, in vitro, in the group of seals fed the Baltic Sea fish. In addition, seals of this group were less able to mount a specific humoral and delayed type hypersensitivity response to a protein antigen, ovalbumin, upon immunization. Increased numbers of granulocytes in this group may have reflected periodic bacterial infections as a consequence of impaired immune function. Their results suggest that pollutants accumulated through the food chain in contaminated marine waters may suppress normal immune responses in marine mammals and lead to an increased susceptibility to opportunistic infection.

  14. Life cycle strategies of bloom-forming, filamentous cyanobacteria in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Suikkanen, Sanna; Kaartokallio, Hermanni; Hällfors, Seija; Huttunen, Maija; Laamanen, Maria

    2010-02-01

    Late-summer blooms of the Nostocalean cyanobacteria Nodularia spumigena, Aphanizomenon flos-aquae and Anabaena spp., occur annually over vast areas of the Baltic Sea. Apart from the planktonic bloom period, the annual cycle of these cyanobacteria is poorly known. With a combination of pelagial monitoring, sedimentation traps and germination experiments, we studied the annual cycle of formation, sedimentation and germination of cyanobacterial akinetes (resting stages) in the northern Baltic Sea during 2005-2006. Akinetes were only rarely encountered in the fall plankton, but they were abundant in the near-bottom sedimentation trap from the middle of July to August. All three taxa formed akinetes, but the numbers of A. flos-aquae akinetes were generally low. Of the three taxa, only Anabaena spp. were regularly found to germinate from the sediment samples. Estimates of Anabaena viable seed bank size ranged from 205 to 1913 akinetes g -1 (ww) of sediment. Aphanizomenon flos-aquae never germinated, and N. spumigena did so only occasionally. It is concluded that the three co-occurring taxa probably have different life cycle strategies, A. flos-aquae being holoplanktonic and Anabaena spp. planktonic during summer, but overwintering as akinetes in the bottom. Summer populations of N. spumigena may originate from both sedimented akinetes and trichomes that overwinter in the water column.

  15. Champacyclin, a New Cyclic Octapeptide from Streptomyces Strain C42 Isolated from the Baltic Sea

    PubMed Central

    Pesic, Alexander; Baumann, Heike I.; Kleinschmidt, Katrin; Ensle, Paul; Wiese, Jutta; Süssmuth, Roderich D.; Imhoff, Johannes F.

    2013-01-01

    New isolates of Streptomyces champavatii were isolated from marine sediments of the Gotland Deep (Baltic Sea), from the Urania Basin (Eastern Mediterranean), and from the Kiel Bight (Baltic Sea). The isolates produced several oligopeptidic secondary metabolites, including the new octapeptide champacyclin (1a) present in all three strains. Herein, we report on the isolation, structure elucidation and determination of the absolute stereochemistry of this isoleucine/leucine (Ile/Leu = Xle) rich cyclic octapeptide champacyclin (1a). As 2D nuclear magnetic resonance (NMR) spectroscopy could not fully resolve the structure of (1a), additional information on sequence and configuration of stereocenters were obtained by a combination of multi stage mass spectrometry (MSn) studies, amino acid analysis, partial hydrolysis and subsequent enantiomer analytics with gas chromatography positive chmical ionization/electron impact mass spectrometry (GC-PCI/EI-MS) supported by comparison to reference dipeptides. Proof of the head-to-tail cyclization of (1a) was accomplished by solid phase peptide synthesis (SPPS) compared to an alternatively side chain cyclized derivative (2). Champacyclin (1a) is likely synthesized by a non-ribosomal peptide synthetase (NRPS), because of its high content of (d)-amino acids. The compound (1a) showed antimicrobial activity against the phytopathogen Erwinia amylovora causing the fire blight disease of certain plants. PMID:24317473

  16. Active bacterial community structure along vertical redox gradients in Baltic Sea sediment

    SciTech Connect

    Jansson, Janet; Edlund, Anna; Hardeman, Fredrik; Jansson, Janet K.; Sjoling, Sara

    2008-05-15

    Community structures of active bacterial populations were investigated along a vertical redox profile in coastal Baltic Sea sediments by terminal-restriction fragment length polymorphism (T-RFLP) and clone library analysis. According to correspondence analysis of T-RFLP results and sequencing of cloned 16S rRNA genes, the microbial community structures at three redox depths (179 mV, -64 mV and -337 mV) differed significantly. The bacterial communities in the community DNA differed from those in bromodeoxyuridine (BrdU)-labeled DNA, indicating that the growing members of the community that incorporated BrdU were not necessarily the most dominant members. The structures of the actively growing bacterial communities were most strongly correlated to organic carbon followed by total nitrogen and redox potentials. Bacterial identification by sequencing of 16S rRNA genes from clones of BrdU-labeled DNA and DNA from reverse transcription PCR (rt-PCR) showed that bacterial taxa involved in nitrogen and sulfur cycling were metabolically active along the redox profiles. Several sequences had low similarities to previously detected sequences indicating that novel lineages of bacteria are present in Baltic Sea sediments. Also, a high number of different 16S rRNA gene sequences representing different phyla were detected at all sampling depths.

  17. Cultivation and isolation of N2-fixing bacteria from suboxic waters in the Baltic Sea.

    PubMed

    Bentzon-Tilia, Mikkel; Farnelid, Hanna; Jürgens, Klaus; Riemann, Lasse

    2014-05-01

    Nitrogenase genes (nifH) from heterotrophic dinitrogen (N2)-fixing bacteria appear ubiquitous in marine bacterioplankton, but the significance of these bacteria for N cycling is unknown. Quantitative data on the N2-fixation potential of marine and estuarine heterotrophs are scarce, and the shortage of cultivated specimens currently precludes ecophysiological characterization of these bacteria. Through the cultivation of diazotrophs from suboxic (1.79 μmol O2 L(-1)) Baltic Sea water in an artificial seawater medium devoid of combined N, we report the cultivability of a considerable fraction of the diazotrophic community in the Gotland Deep. Two nifH clades were present both in situ and in enrichment cultures showing gene abundances of up to 4.6 × 10(5) and 5.8 × 10(5) nifH gene copies L(-1) within two vertical profiles in the Baltic Sea. The distributions of the two clades suggested a relationship with the O2 concentrations in the water column as abundances increased in the suboxic and anoxic waters. It was possible to cultivate and isolate representatives from one of these prevalent clades, and preliminary analysis of their ecophysiology demonstrated growth optima at 0.5-15 μmol O2 L(-1) and 186-194 μmol O2 L(-1) in the absence of combined N. PMID:24579891

  18. Screening level fish community risk assessment of chemical warfare agents in the Baltic Sea.

    PubMed

    Sanderson, Hans; Fauser, Patrik; Thomsen, Marianne; Sørensen, Peter B

    2008-06-15

    Chemical warfare agents (CWAs) have been disposed of in various fashions over the past decades. Significant amounts (approximately 11,000 tonnes) have been dumped in the Baltic Sea east of the island Bornholm following the disarmament of Germany after World War II, causing concerns over potential environmental risks. Absence of risk based on assumptions of extremely low solubility of CWAs cannot alone dismiss these concerns. Existing and modelled fate and effects data were used in the analysis to assess the fish community risk level. The most realistic and also conservative assessment result is the scenario describing 70 m water depth for the most realistic dump-site area with a focus on chronic toxicity, at 0-20 cm above the sediment, yielding a total mixture toxic unit (TU) of 0.62. Triphenylarsine is the CWA with the highest realistic risk profile at 0.2 TU for the fish community followed by Adamsite (0.17), Clark I (0.086) and Yperite (0.083) TU. Adamsite is more persistent and constitutes a potential risk for a longer period than triphenylarsine. The seawater volume potentially at risk is <4 m above sediment and <58 km down current of dump sites. Further risk assessment of dumped CWAs in the Baltic Sea is warranted.

  19. Acetate-utilizing bacteria at an oxic-anoxic interface in the Baltic Sea.

    PubMed

    Berg, Carlo; Beckmann, Sabrina; Jost, Günter; Labrenz, Matthias; Jürgens, Klaus

    2013-08-01

    Pelagic redoxclines represent chemical gradients of elevated microbial activities. While chemolithoautotrophic microorganisms in these systems are well known as catalysts of major biogeochemical cycles, comparable knowledge on heterotrophic organisms is scarce. Thus, in this study, identity and biogeochemical involvement of active heterotrophs were investigated in stimulation experiments and activity measurements based on samples collected from pelagic redoxclines of the central Baltic Sea in 2005 and 2009. In the 2009 samples, (13)C-acetate 16S rRNA stable isotope probing (16S rRNA-SIP) identified gammaproteobacteria affiliated with Colwellia sp. and Neptunomonas sp. in addition to epsilonproteobacteria related to Arcobacter spp. as active heterotrophs at the oxic-anoxic interface layer. Incubations from sulfidic waters were dominated by two phylogenetic subgroups of Arcobacter. In the 2005 samples, organics, manganese(IV), and iron(III) were added to the sulfidic waters, followed by the determination of metal reduction and identification of the stimulated organisms. Here, the same Arcobacter and Colwellia subgroups were stimulated as in 2009, with Arcobacter predominating in samples, in which manganese(IV) reduction was highest. Our results offer new insights into the heterotrophic bacterial assemblage of Baltic Sea pelagic redoxclines and suggest Arcobacter spp. as a heterotroph with presumed relevance also for manganese cycling.

  20. Champacyclin, a new cyclic octapeptide from Streptomyces strain C42 isolated from the Baltic Sea.

    PubMed

    Pesic, Alexander; Baumann, Heike I; Kleinschmidt, Katrin; Ensle, Paul; Wiese, Jutta; Süssmuth, Roderich D; Imhoff, Johannes F

    2013-12-01

    New isolates of Streptomyces champavatii were isolated from marine sediments of the Gotland Deep (Baltic Sea), from the Urania Basin (Eastern Mediterranean), and from the Kiel Bight (Baltic Sea). The isolates produced several oligopeptidic secondary metabolites, including the new octapeptide champacyclin (1a) present in all three strains. Herein, we report on the isolation, structure elucidation and determination of the absolute stereochemistry of this isoleucine/leucine (Ile/Leu = Xle) rich cyclic octapeptide champacyclin (1a). As 2D nuclear magnetic resonance (NMR) spectroscopy could not fully resolve the structure of (1a), additional information on sequence and configuration of stereocenters were obtained by a combination of multi stage mass spectrometry (MSn) studies, amino acid analysis, partial hydrolysis and subsequent enantiomer analytics with gas chromatography positive chmical ionization/electron impact mass spectrometry (GC-PCI/EI-MS) supported by comparison to reference dipeptides. Proof of the head-to-tail cyclization of (1a) was accomplished by solid phase peptide synthesis (SPPS) compared to an alternatively side chain cyclized derivative (2). Champacyclin (1a) is likely synthesized by a non-ribosomal peptide synthetase (NRPS), because of its high content of (D)-amino acids. The compound (1a) showed antimicrobial activity against the phytopathogen Erwinia amylovora causing the fire blight disease of certain plants. PMID:24317473

  1. Hypoxia in the Baltic Sea: biogeochemical cycles, benthic fauna, and management.

    PubMed

    Carstensen, Jacob; Conley, Daniel J; Bonsdorff, Erik; Gustafsson, Bo G; Hietanen, Susanna; Janas, Urzsula; Jilbert, Tom; Maximov, Alexey; Norkko, Alf; Norkko, Joanna; Reed, Daniel C; Slomp, Caroline P; Timmermann, Karen; Voss, Maren

    2014-02-01

    Hypoxia has occurred intermittently over the Holocene in the Baltic Sea, but the recent expansion from less than 10 000 km(2) before 1950 to >60 000 km(2) since 2000 is mainly caused by enhanced nutrient inputs from land and atmosphere. With worsening hypoxia, the role of sediments changes from nitrogen removal to nitrogen release as ammonium. At present, denitrification in the water column and sediments is equally important. Phosphorus is currently buried in sediments mainly in organic form, with an additional contribution of reduced Fe-phosphate minerals in the deep anoxic basins. Upon the transition to oxic conditions, a significant proportion of the organic phosphorus will be remineralized, with the phosphorus then being bound to iron oxides. This iron-oxide bound phosphorus is readily released to the water column upon the onset of hypoxia again. Important ecosystems services carried out by the benthic fauna, including biogeochemical feedback-loops and biomass production, are also lost with hypoxia. The results provide quantitative knowledge of nutrient release and recycling processes under various environmental conditions in support of decision support tools underlying the Baltic Sea Action Plan.

  2. Newly Digitized Historical Climate Data of the German Bight and the Southern Baltic Sea Coasts

    NASA Astrophysics Data System (ADS)

    Röhrbein, Dörte; Tinz, Birger; von Storch, Hans

    2015-04-01

    The detection of historical climate information plays an important role with regard to the discussion on climate change, particularly on storminess. The German Meteorological Service houses huge archives of historical handwritten journals of weather observations. A considerable number of original observation sheets from stations along the coast of the German Bight and the southern Baltic Sea exists which has been until recently almost unnoticed. These stations are called signal stations and are positioned close to the shore. However, for this region meteorological observation data of 128 stations exist from 1877 to 1999 and are partly digitized. In this study we show an analysis of firstly newly digitized wind and surface air pressure data of 15 stations from 1877 to 1939 and we also present a case study of the storm surge at the coast of the southern Baltic Sea in December 1913. The data are quality controlled by formal, climatological, temporal and consistency checks. It is shown that these historical climate data are usable in consistency and quality for further investigations on climate change, e.g. as input for regional and global reanalysis.

  3. Contribution of Regional Climate Drivers to Future Winter Sea-Level Changes in the Baltic Sea Estimated by Statistical Methods and Simulations of Climate Models

    NASA Astrophysics Data System (ADS)

    Hünicke, B.; Zorita, E.

    2008-12-01

    A statistical downscaling approach is applied to the output of different global climate model simulations driven by SRES A2 future scenarios of greenhouse gas concentrations to estimate the contribution of changes in the atmospheric circulation and in precipitation to regional future winter sea-level changes. The method is based on observed statistical relationships between Sea level as predictand and large-scale climate fields as predictors. The approach is applied to the Baltic Sea as it is one of the largest brackish seas in the world and a clear example for a complex coupled ocean-atmosphere land system with a complex coastline and bathymetry. Recent studies indicated that Baltic Sea level variations on decadal and longer time scales are strongly influenced by atmospheric forcings, but the influence of different large-scale forcing factors on sea level vary geographically. While the decadal sea level variations in the northern and eastern Baltic gauges are strongly influenced by the atmospheric circulation, the decadal variations in the southern Baltic Sea can be (statistically) better explained by area-averaged precipitation. The results indicate that future trends in sea-level rise caused by these forcing are larger than the past variability. Using sea level pressure as predictor for the central and eastern Baltic Sea level stations, three climate models lead to 21st century future trends in the range of the order of 1 to 2 mm/year. Using precipitation as predictor for the stations in the Southern Baltic Coast all five models lead to significant trends with a range of the order of 0.4 mm/year. These numbers are smaller, but of the order of magnitude as the predicted future global sea level rise. Nevertheless, these estimations comprise only a partial contribution of selected large-scale regional predictors and an estimation of the total regional sea-level rise has to consider other regional factors such as the isostatic contribution to relative sea

  4. Mapping present and future potential distribution patterns for a meso-grazer guild in the Baltic Sea

    PubMed Central

    Leidenberger, Sonja; De Giovanni, Renato; Kulawik, Robert; Williams, Alan R; Bourlat, Sarah J; Maggs, Christine

    2015-01-01

    Aim The Baltic Sea is one of the world's largest semi-enclosed brackish water bodies characterized by many special features, including endemic species that may be particularly threatened by climate change. We mapped potential distribution patterns under present and future conditions for a community with three trophic levels. We analysed climate-induced changes in the species' distribution patterns and examined possible consequences for the chosen food web. Location Baltic Sea and northern Europe. Methods We developed two open-source workflow-based analytical tools: one for ecological niche modelling and another for raster layer comparison to compute the extent and intensity of change in species' potential distributions. Individual ecological niche models were generated under present conditions and then projected into a future climate change scenario (2050) for a food web consisting of a guild of meso-grazers (Idotea spp.), their host algae (Fucus vesiculosus and Fucus radicans) and their fish predator (Gasterosteus aculeatus). We used occurrence data from the Global Biodiversity Information Facility (GBIF), literature and museum collections, together with five environmental layers at a resolution of 5 and 30 arc-minutes. Results Habitat suitability for Idotea balthica and Idotea chelipes in the Baltic Sea seems to be mostly determined by temperature and ice cover rather than by salinity. 2050 predictions for all modelled species show a northern/north-eastern shift in the Baltic Sea. The distribution ranges for Idotea granulosa and G. aculeatus are predicted to become patchier in the Baltic than in the rest of northern Europe, where the species will gain more suitable habitats. Main conclusions For the Baltic Sea, climate-induced changes resulted in a gain of suitable habitats for F. vesiculosus,I. chelipes and I. balthica, whereas lower habitat suitability was predicted for I. granulosa,F. radicans and G. aculeatus. The predicted north-eastern shift of I. balthica

  5. Submerged terrestrial landscapes in the Baltic Sea: Evidence from multiproxy analyses of sediment cores from Fehmarnbelt

    NASA Astrophysics Data System (ADS)

    Enters, Dirk; Wolters, Steffen; Blume, Katharina; Segschneider, Martin; Lücke, Andreas; Theuerkauf, Martin; Hübener, Thomas

    2016-04-01

    Five sediment cores were taken from the southern part of the Fehmarn Belt (Baltic Sea) in the context of an environmental impact study for the intended fixed traverse between Germany and Denmark. The lithologies of the 8m long cores reveal dramatic changes in sedimentary environments which reflect the early Holocene history of the southern Baltic Sea. A succession of terrestrial, semiterrestrial and limnic facies from glacial sediments to peat, lacustrine/estuarine deposits and finally marine sediments document the interplay of eustatic sea level rise and isostatic rebound, which finally lead to the establishment of marine conditions during the Littorina transgression. An age control of the observed changes was established by dating over 50 C-14 samples of different fractions. During the Lateglacial minerogenic varves with thicknesses of several centimeters verify the existence of a proglacial lake in the Fehmarnbelt. Peat development started around 11.250 cal. BP and terminated ca. 10.600 cal. BP which is roughly contemporaneous with the end of the Yoldia Phase in the central Baltic Sea. The oldest peat layers consist of undecomposed sedges and reed. Woody remains of willows appear not before 10.700 cal BP and indicate a stagnant or slowly decreasing water table. This semi-terrestrial phase is followed by a shallow inland lake which existed until the Littorina transgression around 8.300 cal. BP. Initially the lacustrine sediments exhibit high C/N ratios, low low δ13Corg values and contain numerous wood fragments as well as other botanical macro remains. This indicates shallow conditions close to the lake shore. Later, the occurrence of planktonic diatom species such as Aulacoseira ambigua suggest greater water depths. We did not find any indications of the often postulated catastrophic outburst of the Ancylus Lake via Fehmarnbelt and the Great Belt into the North Sea. Likewise, XRF scanning does not show conspicuous peaks in Ti or K which would have been

  6. Water protection in the Baltic Sea and the Chesapeake Bay: institutions, policies and efficiency.

    PubMed

    Iho, Antti; Ribaudo, Marc; Hyytiäinen, Kari

    2015-04-15

    The Baltic Sea and the Chesapeake Bay share many characteristics. Both are shallow, brackish marine areas that suffer from eutrophication. Successful policies targeting point source pollution have lowered nutrient loads in both areas, but achieving the desired marine quality will require further abatement: efforts may be extended to more complicated and expensive pollution sources, notably agricultural nonpoint loads. Despite their ecological similarities, the two watersheds have different histories and institutional settings and have thus adopted different policies. Comparing and contrasting the policies reveal ways to improve the efficiency of each and ways to avoid the path of trial and error. No comparison of the parallel protection efforts, which involve expenditures of hundreds of millions of dollars annually, has been carried out to date. The present paper analyzes the policies applied in the two regions, distilling the results into six recommendations for future steps in preserving what are valuable sea areas. PMID:25752532

  7. Prospects for cost-efficient water protection in the Baltic Sea.

    PubMed

    Hyytiäinen, Kari; Ahlvik, Lassi

    2015-01-15

    This study investigates the economic consequences of the nutrient load reductions agreed in the 2013 revision of the Baltic Sea Action Plan. The cost of meeting the targets set for waterborne sources was estimated to be 1980 MEUR annually. The 2013 revision is a step towards cost-efficient water protection: the cost of meeting the earlier targets would have been 328 MEUR (14%) higher, although the revised targets are now more ambitious with respect to phosphorus. We demonstrate that there is potential for efficiency gains by introducing flexibility mechanisms, such as 'joint implementation' to trans-boundary water protection. The potential gains can be as high as 280 MEUR (14%). The most flexible interpretation of the basin targets, one allowing Contracting Parties to account for reductions in other sea basins in proportion to their effect in the focal basin, could further reduce the total cost by 200 MEUR (12%). PMID:25467871

  8. Reducing agricultural nitrogen inputs in the German Baltic Sea catchment - trends and policy options.

    PubMed

    Ackermann, Andrea; Mahnkopf, Judith; Heidecke, Claudia; Venohr, Markus

    2016-01-01

    We depict recent agricultural nitrogen input and future loads to be expected in 2021 in the German Baltic Sea catchment to assess the feasibility of reaching water quality targets defined by the Marine Strategy Framework Directive (MSFD). We calculate recent and future nitrogen balances from agriculture by applying an interdisciplinary modelling system, also considering the effects of the Nitrate Directive. The nitrogen surpluses are transferred to a nutrient emission model to simulate nitrogen emissions, in-stream retention and resulting riverine loads to the sea until 2021. Finally, we analyse input reduction demands and agri-environmental measures necessary to attain water quality targets of the MSFD. The results are target-oriented mitigation options relevant for implementation, based on regional land use and nitrogen reduction demands. Furthermore, this paper discusses the effects of policies and measures implemented to reduce nitrogen loads. PMID:27642825

  9. Water protection in the Baltic Sea and the Chesapeake Bay: institutions, policies and efficiency.

    PubMed

    Iho, Antti; Ribaudo, Marc; Hyytiäinen, Kari

    2015-04-15

    The Baltic Sea and the Chesapeake Bay share many characteristics. Both are shallow, brackish marine areas that suffer from eutrophication. Successful policies targeting point source pollution have lowered nutrient loads in both areas, but achieving the desired marine quality will require further abatement: efforts may be extended to more complicated and expensive pollution sources, notably agricultural nonpoint loads. Despite their ecological similarities, the two watersheds have different histories and institutional settings and have thus adopted different policies. Comparing and contrasting the policies reveal ways to improve the efficiency of each and ways to avoid the path of trial and error. No comparison of the parallel protection efforts, which involve expenditures of hundreds of millions of dollars annually, has been carried out to date. The present paper analyzes the policies applied in the two regions, distilling the results into six recommendations for future steps in preserving what are valuable sea areas.

  10. Local adaptation and oceanographic connectivity patterns explain genetic differentiation of a marine diatom across the North Sea–Baltic Sea salinity gradient

    PubMed Central

    Sjöqvist, C; Godhe, A; Jonsson, P R; Sundqvist, L; Kremp, A

    2015-01-01

    Drivers of population genetic structure are still poorly understood in marine micro-organisms. We exploited the North Sea–Baltic Sea transition for investigating the seascape genetics of a marine diatom, Skeletonema marinoi. Eight polymorphic microsatellite loci were analysed in 354 individuals from ten locations to analyse population structure of the species along a 1500-km-long salinity gradient ranging from 3 to 30 psu. To test for salinity adaptation, salinity reaction norms were determined for sets of strains originating from three different salinity regimes of the gradient. Modelled oceanographic connectivity was compared to directional relative migration by correlation analyses to examine oceanographic drivers. Population genetic analyses showed distinct genetic divergence of a low-salinity Baltic Sea population and a high-salinity North Sea population, coinciding with the most evident physical dispersal barrier in the area, the Danish Straits. Baltic Sea populations displayed reduced genetic diversity compared to North Sea populations. Growth optima of low salinity isolates were significantly lower than those of strains from higher native salinities, indicating local salinity adaptation. Although the North Sea–Baltic Sea transition was identified as a barrier to gene flow, migration between Baltic Sea and North Sea populations occurred. However, the presence of differentiated neutral markers on each side of the transition zone suggests that migrants are maladapted. It is concluded that local salinity adaptation, supported by oceanographic connectivity patterns creating an asymmetric migration pattern between the Baltic Sea and the North Sea, determines genetic differentiation patterns in the transition zone. PMID:25892181

  11. Past occurrences of hypoxia in the Baltic Sea and the role of climate variability, environmental change and human impact

    NASA Astrophysics Data System (ADS)

    Zillén, Lovisa; Conley, Daniel J.; Andrén, Thomas; Andrén, Elinor; Björck, Svante

    2008-12-01

    The hypoxic zone in the Baltic Sea has increased in area about four times since 1960 and widespread oxygen deficiency has severely reduced macro benthic communities below the halocline in the Baltic Proper and the Gulf of Finland, which in turn has affected food chain dynamics, fish habitats and fisheries in the entire Baltic Sea. The cause of increased hypoxia is believed to be enhanced eutrophication through increased anthropogenic input of nutrients, such as nitrogen and phosphorus. However, the spatial variability of hypoxia on long time-scales is poorly known: and so are the driving mechanisms. We review the occurrence of hypoxia in modern time (last c. 50 years), modern historical time (AD 1950-1800) and during the more distant past (the last c. 10 000 years) and explore the role of climate variability, environmental change and human impact. We present a compilation of proxy records of hypoxia (laminated sediments) based on long sediment cores from the Baltic Sea. The cumulated results show that the deeper depressions of the Baltic Sea have experienced intermittent hypoxia during most of the Holocene and that regular laminations started to form c. 8500-7800 cal. yr BP ago, in association with the formation of a permanent halocline at the transition between the Early Littorina Sea and the Littorina Sea s. str. Laminated sediments were deposited during three main periods (i.e. between c. 8000-4000, 2000-800 cal. yr BP and subsequent to AD 1800) which overlap the Holocene Thermal Maximum (c. 9000-5000 cal. yr BP), the Medieval Warm Period (c. AD 750-1200) and the modern historical period (AD 1800 to present) and coincide with intervals of high surface salinity (at least during the Littorina s. str.) and high total organic carbon content. This study implies that there may be a correlation between climate variability in the past and the state of the marine environment, where milder and dryer periods with less freshwater run-off correspond to increased salinities

  12. Model studies of the flux of CO{sub 2} over the air-sea interface in the Baltic Sea

    SciTech Connect

    Ohlson, M.

    1994-12-31

    In the discussion about the green house effect generated by the burning of fossil fuels, carbon dioxide (CO{sub 2}) has a key role. A major part of the surplus CO{sub 2} has been suggested, by the scientific community, to be withdrawn from the atmosphere and to be taken up by the growth in continental shelf areas with high primary production, and in terrestrial forests. The exact quantity and reaction ways and mechanisms of those processes are not known today. The Baltic Sea is, for several reasons, a well chosen area to study this phenomenon. It is a shallow continental Mediterranean sea, in this area almost the first measurements of the carbonate system were carried out in the end of the last century. This has resulted in long time series of measurements of the carbonate system available for use in, e.g. modelling work, a working numerical carbonate model.

  13. Discovery of bacterial polyhydroxyalkanoate synthase (PhaC)-encoding genes from seasonal Baltic Sea ice and cold estuarine waters.

    PubMed

    Pärnänen, Katariina; Karkman, Antti; Virta, Marko; Eronen-Rasimus, Eeva; Kaartokallio, Hermanni

    2015-01-01

    Polyhydroxyalkanoates (PHAs) are macromolecules produced by bacteria as means for storing carbon and energy in intracellular granules. PHAs have physical properties similar to those of plastics and have become of interest to industry as materials for environmentally friendly bioplastic production. There is an ongoing search for new PHA-producing bacterial strains and PHA-synthesizing enzymes tolerating extreme conditions to find ways of producing PHAs at cold temperatures and high solute concentrations. Moreover, the study of PHA producers in the sea-ice biome can aid in understanding the microbial ecology of carbon cycling in ice-associated ecosystems. In this study, PHA producers and PHA synthase genes were examined under the extreme environmental conditions of sea ice and cold seawater to find evidence of PHA production in an environment requiring adaptation to high salinity and cold temperatures. Sea ice and cold estuarine water samples were collected from the northern Baltic Sea and evidence of PHA production was gathered, using microscopy with Nile Blue A staining of PHA-granules and PCR assays detecting PHA-synthesis genes. The PHA granules and PHA synthases were found at all sampling locations, in both sea ice and water, and throughout the sampling period spanning over 10 years. Our study shows, for the first time, that PHA synthesis occurs in Baltic Sea cold-adapted bacteria in their natural environment, which makes the Baltic Sea and its cold environments an interesting choice in the quest for PHA-synthesizing bacteria and synthesis genes. PMID:25280551

  14. Development of interdisciplinary model of microplastics transport and transformation in the Baltic sea

    NASA Astrophysics Data System (ADS)

    Bagaev, Andrei; Chubarenko, Irina; Mizyuk, Artem; Zobkov, Mikhail; Esiukova, Elena; Isachenko, Igor; Stepanova, Natalya

    2016-04-01

    Nowadays, anthropogenic pressure from the coastal areas comes up in many aspects of marine environment changes, decreasing the aesthetics of the underwater world, threatening the sustainability of marine ecosystems and influencing the quality of human life. Microplastics are pervasive throughout the marine environment, are ingested by many marine organisms, and enter a food chain that includes humans. A certain fraction of microplastics in marine environment results from breakdown of larger items in numerous tiny fragments due to mechanical forces and photochemical processes, as well as from other degradation sources. Microplastics can absorb high levels of Persistent Organic Pollutants (POPs) and other toxins. Deep-sea sediments are a likely, but yet unquantified, sink for microplastics (Cole et al., 2011). Since the MARBLE ('MicroplAstics Research in the BaLtic Environment') project started, three expeditions and multiple on-shore field experiments have been conducted in the South-Eastern Baltic. The samples were collected from the surface, deep water layers and bottom sediments. The samples were processed and physical parameters of the microparticles were established. In parallel, laboratory experiments under controllable conditions over the particles of regular shapes were conducted in order to test the empirical formulas for the sinking velocity. PLEX ('PLastics EXplorer') -- a device for efficiently collecting microparticles in marine environment -- was developed, built and tested. An attempt was made to quantify some geometrical properties of particles, to compare their surface areas, fouling rates, sinking velocities, and finally provide some estimates for the main spatial and temporal scales, describing the behaviour of the particles of different densities and shapes in the Baltic Sea (Chubarenko et al., 2016). An original 3D model of Microplastics dynamics is under development now. Its aim is to provide a robust numerical predictive tool to study pathways

  15. Effects of surface current-wind interaction in an eddy-rich general ocean circulation simulation of the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Dietze, Heiner; Löptien, Ulrike

    2016-08-01

    Deoxygenation in the Baltic Sea endangers fish yields and favours noxious algal blooms. Yet, vertical transport processes ventilating the oxygen-deprived waters at depth and replenishing nutrient-deprived surface waters (thereby fuelling export of organic matter to depth) are not comprehensively understood. Here, we investigate the effects of the interaction between surface currents and winds on upwelling in an eddy-rich general ocean circulation model of the Baltic Sea. Contrary to expectations we find that accounting for current-wind effects inhibits the overall vertical exchange between oxygenated surface waters and oxygen-deprived water at depth. At major upwelling sites, however (e.g. off the southern coast of Sweden and Finland) the reverse holds: the interaction between topographically steered surface currents with winds blowing over the sea results in a climatological sea surface temperature cooling of 0.5 K. This implies that current-wind effects drive substantial local upwelling of cold and nutrient-replete waters.

  16. Significance of archaeal nitrification in hypoxic waters of the Baltic Sea.

    PubMed

    Berg, Carlo; Vandieken, Verona; Thamdrup, Bo; Jürgens, Klaus

    2015-06-01

    Ammonia-oxidizing archaea (AOA) of the phylum Thaumarchaeota are widespread, and their abundance in many terrestrial and aquatic ecosystems suggests a prominent role in nitrification. AOA also occur in high numbers in oxygen-deficient marine environments, such as the pelagic redox gradients of the central Baltic Sea; however, data on archaeal nitrification rates are scarce and little is known about the factors, for example sulfide, that regulate nitrification in this system. In the present work, we assessed the contribution of AOA to ammonia oxidation rates in Baltic deep basins and elucidated the impact of sulfide on this process. Rate measurements with (15)N-labeled ammonium, CO(2) dark fixation measurements and quantification of AOA by catalyzed reporter deposition-fluorescence in situ hybridization revealed that among the three investigated sites the highest potential nitrification rates (122-884 nmol l(-1)per day) were measured within gradients of decreasing oxygen, where thaumarchaeotal abundance was maximal (2.5-6.9 × 10(5) cells per ml) and CO(2) fixation elevated. In the presence of the archaeal-specific inhibitor GC(7), nitrification was reduced by 86-100%, confirming the assumed dominance of AOA in this process. In samples spiked with sulfide at concentrations similar to those of in situ conditions, nitrification activity was inhibited but persisted at reduced rates. This result together with the substantial nitrification potential detected in sulfidic waters suggests the tolerance of AOA to periodic mixing of anoxic and sulfidic waters. It begs the question of whether the globally distributed Thaumarchaeota respond similarly in other stratified water columns or whether the observed robustness against sulfide is a specific feature of the thaumarchaeotal subcluster present in the Baltic Deeps.

  17. Significance of archaeal nitrification in hypoxic waters of the Baltic Sea

    PubMed Central

    Berg, Carlo; Vandieken, Verona; Thamdrup, Bo; Jürgens, Klaus

    2015-01-01

    Ammonia-oxidizing archaea (AOA) of the phylum Thaumarchaeota are widespread, and their abundance in many terrestrial and aquatic ecosystems suggests a prominent role in nitrification. AOA also occur in high numbers in oxygen-deficient marine environments, such as the pelagic redox gradients of the central Baltic Sea; however, data on archaeal nitrification rates are scarce and little is known about the factors, for example sulfide, that regulate nitrification in this system. In the present work, we assessed the contribution of AOA to ammonia oxidation rates in Baltic deep basins and elucidated the impact of sulfide on this process. Rate measurements with 15N-labeled ammonium, CO2 dark fixation measurements and quantification of AOA by catalyzed reporter deposition–fluorescence in situ hybridization revealed that among the three investigated sites the highest potential nitrification rates (122–884 nmol l−1per day) were measured within gradients of decreasing oxygen, where thaumarchaeotal abundance was maximal (2.5–6.9 × 105 cells per ml) and CO2 fixation elevated. In the presence of the archaeal-specific inhibitor GC7, nitrification was reduced by 86–100%, confirming the assumed dominance of AOA in this process. In samples spiked with sulfide at concentrations similar to those of in situ conditions, nitrification activity was inhibited but persisted at reduced rates. This result together with the substantial nitrification potential detected in sulfidic waters suggests the tolerance of AOA to periodic mixing of anoxic and sulfidic waters. It begs the question of whether the globally distributed Thaumarchaeota respond similarly in other stratified water columns or whether the observed robustness against sulfide is a specific feature of the thaumarchaeotal subcluster present in the Baltic Deeps. PMID:25423026

  18. Evidence of a hybrid-zone in Atlantic cod (Gadus morhua) in the Baltic and the Danish Belt Sea revealed by individual admixture analysis.

    PubMed

    Nielsen, Einar E; Hansen, Michael M; Ruzzante, Daniel E; Meldrup, Dorte; Grønkjaer, Peter

    2003-06-01

    The study of hybrid zones is central to our understanding of the genetic basis of reproductive isolation and speciation, yet very little is known about the extent and significance of hybrid zones in marine fishes. We examined the population structure of cod in the transition area between the North Sea and the Baltic Sea employing nine microsatellite loci. Genetic differentiation between the North Sea sample and the rest increased along a transect to the Baltic proper, with a large increase in level of differentiation occurring in the Western Baltic area. Our objective was to determine whether this pattern was caused purely by varying degrees of mechanical mixing of North Sea and Baltic Sea cod or by interbreeding and formation of a hybrid swarm. Simulation studies revealed that traditional Hardy-Weinberg analysis did not have sufficient power for detection of a Wahlund effect. However, using a model-based clustering method for individual admixture analysis, we were able to demonstrate the existence of intermediate genotypes in all samples from the transition area. Accordingly, our data were explained best by a model of a hybrid swarm flanked by pure nonadmixed populations in the North Sea and the Baltic Sea proper. Significant correlation of gene identities across loci (gametic phase disequilibrium) was found only in a sample from the Western Baltic, suggesting this area as the centre of the apparent hybrid zone. A hybrid zone for cod in the ecotone between the high-saline North Sea and the low-saline Baltic Sea is discussed in relation to its possible origin and maintenance, and in relation to a classical study of haemoglobin variation in cod from the Baltic Sea/Danish Belt Sea, suggesting mixing of two divergent populations without interbreeding.

  19. Seasonal contribution of terrestrial organic matter and biological oxygen demand to the Baltic Sea from three contrasting river catchments

    NASA Astrophysics Data System (ADS)

    Reader, H. E.; Stedmon, C. A.; Kritzberg, E. S.

    2014-06-01

    To examine the potential influence of terrestrially derived DOM on the Baltic Sea, a year-long study of dissolved organic matter (DOM) was performed in three river catchments in Sweden. One catchment drains into the Bothnian Sea, while two southern catchments drain into the Baltic proper. Dissolved organic carbon (DOC) concentrations were positively correlated with discharge from forested catchments over the year. While the overall concentrations of DOC were several times higher in the southern two catchments, higher discharge in the northern catchment resulted in the annual loadings of DOC being on the same order of magnitude for all three catchments. Biological oxygen demand (BOD) was used as a proxy for the lability of carbon in the system. The range of BOD values was similar for all three catchments, however, the ratio of BOD to DOC (an indication of the labile fraction) in Ume river was four times higher than in the southern two catchments. Total annual BOD loading to the Baltic Sea was twice as high in the northern catchment than in the two southern catchments. Lower winter temperatures and preservation of organic matter in the northern catchment combined with an intense spring flood help to explain the higher concentrations of labile carbon in the northern catchment. Lower lability of DOM as well as higher colour in the southern catchments suggest that wetlands (i.e. peat bogs) may be the dominant source of DOM in these catchments, particularly in periods of low flow. With climate change expected to increase precipitation events and temperatures across the region, the supply and quality of DOM delivered to the Baltic Sea can also be expected to change. Our results indicate that DOM supply to the Baltic Sea from boreal rivers will be more stable throughout the year, and potentially have a lower bioavailability.

  20. Assessment the Synoptic Variability of Vertical Thermal Structure in Baltic Sea Waters on the Base of in-situ Measurements

    NASA Astrophysics Data System (ADS)

    Koch, A.; Klevantsov, J.; Rozhkov, V.

    2004-12-01

    The thermal regime of sea's active layer is determined by its interaction with atmosphere, thermal balance, wind and convective water mixing. The question about assessment of synoptic variability of thermal stratification in Baltic Sea waters has not yet solved. The purpose of the present work was to determine the bounds of synoptic variability of vertical temperature profiles T(z) at the all seasons on the example of Bornholm Basin in the Baltic Sea. On the base of the large array of episodic measurements at the international stations BY, situated in key regions of the Baltic Sea, the principles of annual rhythmic of vertical distribution of water temperature are given in the paper [1]. However, this data does not allow separate the synoptic variability from seasonal and inter-annual diapasons, since measurements at fixed horizon belong to different synoptic events at different years. During 1978-1988 the State Oceanographic Institute (Leningrad/Saint-Petersburg Branch) on the base of Russian RV "Rudolf Samoylovich" was carrying out observations of hydrological and hydro-chemical elements of Baltic Sea waters at the stations BY [2]. The originality of carried out work is that for the first time continuous series of measurements for elements of vertical thermo-haline structure with duration from day to several months and discreteness of 3 hour were executed. These observations got name "Multi-daily Stations". This data alongside with the data of episodic observations allows separate synoptic variability of water temperature profile and assess its degree. Vertical thermal structure of sea waters has been typified based on the parameters of profile geometry. The degree of synoptic variability in each element of profile T(z) for all the seasons has determined. It has been showed, that the enthalpy is the optimal thermal regime parameter for separating the synoptic diapason from others. It has also been showed, that synoptic variability of water temperature in deep

  1. Transformation of the Lake Ladoga-Baltic Sea water connection during the Holocene

    NASA Astrophysics Data System (ADS)

    Subetto, D.; Kuznetsov, D.; Ludikova, A.; Sapelko, T.; Averichkin, O.

    2009-04-01

    1. In this presentation we will present results of complex paleolimnological and archeological studies several lakes in the Karelian Isthmus, NW Russia, located along the former Ladoga-Baltic water-system connection. Complementary field expeditions were organized in 2007 and 2008 in order to core lakes Volojarvi, Makarovskoye, Lamskoye, Uzlovoye and a lake on the Isl.Puutsaari, Northern Ladoga. 2. The ancient water connection between Lake Ladoga and the Baltic in the northern lowland of the Karelian Isthmus has been originated after the ice retreating ca 14,000-12,000 cal BP. At that time, until the catastrophic dropping of the Baltic Ice Lake (BIL) water-level happened ca 11,500 cal BP, Lake Ladoga was a deep easternmost bay of the BIL. During the BIL stage the highest shoreline reached c. 50-60 m a.s.l. in the northern part of the Karelian Isthmus. All studied lakes were flooded the BIL waters. Varved-type clay sediments were formed at that time 3. Arctic climatic and environmental conditions with stagnant ice/permafrost and sparse shrub, herb and grass vegetation on barren soils characterized the central highland of the Karelian Isthmus prior to 12,650 cal yrs BP. Steppe-tundra and cold, dry conditions are inferred between 12,650-11,200/11,000 cal yrs BP. 4. After 11,500 cal BP a straight/river existed in the northern part of the Karelian Isthmus during ca 7000 years. 5. During the Yoldia Sea regression of the Baltic (11500-11 000 cal. BP) Lake Ladoga was re-connected with the Baltic. Water level of Lake Ladoga and lakes in its basin was dropped. The vegetation was arctic tundra with sparse vegetation, which made the soils susceptible to erosion as reflected by the silty clayey sediments in Lake Ladoga. Most of the studied lakes were isolated. 6. The earliest evidence of human settlement in north-eastern Baltic Area is attested at Antrea-Korpilahti (11,200-10,250 cal BP) where artifacts were found in the deposits of a channel between the Baltic and the Ladoga

  2. Disentangling the role of atmospheric and oceanic conditions in the occurrence of major Baltic inflows: The importance of haline stratification in the Belt Sea.

    NASA Astrophysics Data System (ADS)

    Höflich, Katharina; Lehmann, Andreas; Myrberg, Kai

    2016-04-01

    The Baltic Sea is a semi-enclosed body of water connected to the North Sea only via the shallow and narrow Danish Straits. Of special importance to the salinity dynamics of the Baltic Sea are so-called major Baltic inflows (highly saline barotropic inflows), that also comprise the only process by which oxygen is supplied to below halocline water masses. Large barotropic inflows (or large volume changes) of the Baltic Sea can be identified from the sea level at Landsort, where the number of large barotropic inflows is found to exceed the number of major Baltic inflows. The occurrence of major Baltic inflows is typically attributed to a sequence of large-scale easterly and westerly atmospheric circulation patterns, that have recently also been linked to the occurrence of large barotropic inflows in general. In this context the widely accepted view that atmospheric conditions (and hence the evolution of the sea level in the North Sea - Baltic Sea system) are of exclusive importance to the occurrence of major Baltic inflows becomes questionable. In this study we attempt to disentangle the role of oceanic and atmospheric conditions to the occurrence of highly saline barotropic inflows, with special focus on the role of the hydrographic conditions in the Belt Sea. For the period 1979 - 2015 and using a realistic three-dimensional numerical ocean model of the Baltic Sea we find that the salinity of the barotropic inflow significantly depends on the availability of saline water masses in the Belt Sea. However, detailed investigation on the time evolution of the single barotropic inflow reveals differences in the rapidness and magnitude of the inflow events. Both are in fact good predictors for the salinity of the inflow, highlighting that within the set of large barotropic inflows also differing atmospheric conditions must play some role in the formation of the salinity of the inflowing water mass. In order to further specify the importance of the hydrographic conditions

  3. Spring blooms in the Baltic Sea have weakened but lengthened from 2000 to 2014

    NASA Astrophysics Data System (ADS)

    Groetsch, Philipp M. M.; Simis, Stefan G. H.; Eleveld, Marieke A.; Peters, Steef W. M.

    2016-09-01

    Phytoplankton spring bloom phenology was derived from a 15-year time series (2000-2014) of ship-of-opportunity chlorophyll a fluorescence observations collected in the Baltic Sea through the Alg@line network. Decadal trends were analysed against inter-annual variability in bloom timing and intensity, and environmental drivers (nutrient concentration, temperature, radiation level, wind speed).Spring blooms developed from the south to the north, with the first blooms peaking mid-March in the Bay of Mecklenburg and the latest bloom peaks occurring mid-April in the Gulf of Finland. Bloom duration was similar between sea areas (43 ± 2 day), except for shorter bloom duration in the Bay of Mecklenburg (36 ± 11 day). Variability in bloom timing increased towards the south. Bloom peak chlorophyll a concentrations were highest (and most variable) in the Gulf of Finland (20.2 ± 5.7 mg m-3) and the Bay of Mecklenburg (12.3 ± 5.2 mg m-3).Bloom peak chlorophyll a concentration showed a negative trend of -0.31 ± 0.10 mg m-3 yr-1. Trend-agnostic distribution-based (Weibull-type) bloom metrics showed a positive trend in bloom duration of 1.04 ± 0.20 day yr-1, which was not found with any of the threshold-based metrics. The Weibull bloom metric results were considered representative in the presence of bloom intensity trends.Bloom intensity was mainly determined by winter nutrient concentration, while bloom timing and duration co-varied with meteorological conditions. Longer blooms corresponded to higher water temperature, more intense solar radiation, and lower wind speed. It is concluded that nutrient reduction efforts led to decreasing bloom intensity, while changes in Baltic Sea environmental conditions associated with global change corresponded to a lengthening spring bloom period.

  4. Mercury in precipitation over the coastal zone of the southern Baltic Sea, Poland.

    PubMed

    Siudek, Patrycja; Falkowska, Lucyna; Brodecka, Aleksandra; Kowalski, Artur; Frankowski, Marcin; Siepak, Jerzy

    2015-02-01

    An investigation of atmospheric mercury was conducted in the urban coastal zone of the Gulf of Gdansk (Baltic Sea, Poland) in 2008. Rainwater samples were collected in bulk samplers and Hg concentration was determined using AAS method. Total mercury concentration ranged from 1.9 to 14.8 ng l(-1) (the mean was 8.3 ng l(-1) with standard deviation ±3.7), out of which about 34 % were water-soluble Hg(II) forms. Distribution of Hg species in rainwater was related to both the emission source and the atmospheric processes. During the sampling period, two maxima of Hg concentration in precipitation were observed: the first in the cold season and the second one in the warm season. Elevated concentrations of Hg in wintertime precipitation were generally the result of local urban atmospheric emission connected with the following anthropogenic sources: intensive combustion of fossil fuels in domestic furnaces, individual power/heat generating plants, and motor vehicles. During summertime, Hg° re-emitted from contaminated land and sea surfaces was photochemically oxidized by active atmospheric substances (e.g., hydroxyl radicals, hydrogen peroxide, halogens) and could be an additional source of atmospherically deposited Hg. The results presented in this work indicate that rainwater Hg concentration and deposition values are not much higher in comparison with other urban locations along the Baltic Sea basin and other coastal cities. However, the elevated mercury concentration in rainwater and, consequently, higher deposition ratio could appear occasionally as an effect of intensive anthropogenic emissions (domestic heating) and/or photochemical reactions.

  5. Iron oxide reduction in deep Baltic Sea sediments: the potential role of anaerobic oxidation of methane

    NASA Astrophysics Data System (ADS)

    Egger, Matthias; Slomp, Caroline P.; Dijkstra, Nikki; Sapart, Célia J.; Risgaard-Petersen, Nils; Kasten, Sabine; Riedinger, Natascha; Barker Jørgensen, Bo

    2015-04-01

    Methane is a powerful greenhouse gas and its emission from marine sediments to the atmosphere is largely controlled by anaerobic oxidation of methane (AOM). Traditionally, sulfate is considered to be the most important electron acceptor for AOM in marine sediments. However, recent studies have shown that AOM may also be coupled to the reduction of iron (Fe) oxides (Beal et al., 2009; Riedinger et al., 2014; Egger et al., 2014). In the Baltic Sea, the transition from the Ancylus freshwater phase to the Littorina brackish/marine phase (A/L-transition) ca. 9-7 ka ago (Zillén et al., 2008) resulted in the accumulation of methanogenic brackish/marine sediments overlying Fe-oxide rich lacustrine deposits. The downward diffusion of methane from the brackish/marine sediments into the lake sediments leads to an ideal diagenetic system to study a potential coupling between Fe oxide reduction and methane oxidation. Here, we use porewater and sediment geochemical data obtained at sites M0063 and M0065 during the IODP Baltic Sea Paleoenvironment Expedition 347 in 2013 to identify the potential mechanisms responsible for the apparent Fe oxide reduction in the non-sulfidic limnic sediments below the A/L transition. In this presentation, we will review the various explanations for the elevated ferrous Fe in the porewater in the lake sediments and we will specifically address the potential role of the reaction of methane with Fe-oxides. References: Beal E. J., House C. H. and Orphan V. J. (2009) Manganese- and iron-dependent marine methane oxidation. Science 325, 184-187. Egger M., Rasigraf O., Sapart C. J., Jilbert T., Jetten M. S. M., Röckmann T., van der Veen C., Banda N., Kartal B., Ettwig K. F. and Slomp C. P. (2014) Iron-mediated anaerobic oxidation of methane in brackish coastal sediments. Environ. Sci. Technol. 49, 277-283. Riedinger N., Formolo M. J., Lyons T. W., Henkel S., Beck A. and Kasten S. (2014) An inorganic geochemical argument for coupled anaerobic oxidation of

  6. Microbial decomposition of terrigenic organic matter discharged into the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Manecki, M.; Herlemann, D.; Pollehne, F.; Labrenz, M.; Zimmermann, R.; Dittmar, T.; Schulz-Bull, D.; Jürgens, K.

    2012-04-01

    The permafrost soils in arctic regions contain a large amount of the worldwide organic carbon and global warming is expected to increase drainage of dissolved organic matter (DOM) into the adjacent oceans. It is yet unclear how this terrigenic organic matter will influence the global carbon cycle and the feedback effects to the climate. We used the Baltic Sea as a model system to investigate the role of abiotic factors on the degradation of terrigenic dissolved organic matter (tDOM) upon discharge into a brackish system as well as the response of the microbial community. Water from the Kalix River in Northern Sweden, which drains also permafrost soils, was used as the tDOM source in incubation experiments with Baltic Sea water. Different qualities of tDOM were compared by applying concentration procedures: tDOM was added to fresh Baltic Sea water as untreated Kalix River water or concentrated by commonly use DOC concentration procedures (lyophilization, ultrafiltration, solid phase extraction). We investigated the TDOC degradation by parallel measurements of dissolved organic carbon (DOC) consumption, DOM composition (using a 15 Tesla Fourier Transformation Ion Cyclotron Resonance Mass Spectrometer (FT-ICR-MS)), microbial activities and microbial community structure. FT-ICR-MS measurements showed qualitative differences in the DOM compositions for the different treatments and a drastic change in DOM composition between the third and fourth week of the incubation experiment. Despite the qualitative differences in DOM composition, the results obtained so far revealed that the added tDOC had, independent of the previous enrichment procedure, only little influence on bacterial activities, bacterial community structure and DOC decomposition dynamics. This indicates that the major portion of the added tDOC is of refractory nature. Instead, bacterial predation by heterotrophic protists had a strong impact on both bacterial community structure and DOC decomposition

  7. Immunological responses in the mussel Mytilus trossulus transplanted at the coastline of the northern Baltic Sea.

    PubMed

    Höher, N; Turja, R; Köhler, A; Lehtonen, K K; Broeg, K

    2015-12-01

    The applicability of immune responses in transplanted Baltic blue mussels (Mytilus trossulus) as biomarkers of immunotoxic effects was studied at differently contaminated locations in the Gulf of Bothnia (northern Baltic Sea). Here, we present a detailed report on the immune responses measured as complementary part of transplantation study by Turja et al. (2014).Various immunological endpoints such as total and differential cell count, morphological alterations,phagocytic activity, and caspase 3/7 activity of mussel haemocytes as well as haemolytic activity of the haemolymph were used. Mussels collected at a reference site at a Finnish coastal site (Hanko, H) were transplanted at the Swedish coast near industrial and urban regions of the cities Sundsvall (S1, S2) and Gävle (G1, G2), respectively. Based on the measured immunological responses, multivariate statistical analysis (PCA biplot) showed a clear separation of the most polluted site S1, indicating immunotoxic impacts of the mixture of contaminants present at this location. Based on these observations and results from Turja et al. (2014), we suggest the implementation of immunotoxic biomarkers for the evaluation of ecosystem health. However, these should be accompanied by complementary endpoints of biological effects encompassing i.e., physiological, antioxidant and bioenergetic markers. PMID:26604022

  8. Immunological responses in the mussel Mytilus trossulus transplanted at the coastline of the northern Baltic Sea.

    PubMed

    Höher, N; Turja, R; Köhler, A; Lehtonen, K K; Broeg, K

    2015-12-01

    The applicability of immune responses in transplanted Baltic blue mussels (Mytilus trossulus) as biomarkers of immunotoxic effects was studied at differently contaminated locations in the Gulf of Bothnia (northern Baltic Sea). Here, we present a detailed report on the immune responses measured as complementary part of transplantation study by Turja et al. (2014).Various immunological endpoints such as total and differential cell count, morphological alterations,phagocytic activity, and caspase 3/7 activity of mussel haemocytes as well as haemolytic activity of the haemolymph were used. Mussels collected at a reference site at a Finnish coastal site (Hanko, H) were transplanted at the Swedish coast near industrial and urban regions of the cities Sundsvall (S1, S2) and Gävle (G1, G2), respectively. Based on the measured immunological responses, multivariate statistical analysis (PCA biplot) showed a clear separation of the most polluted site S1, indicating immunotoxic impacts of the mixture of contaminants present at this location. Based on these observations and results from Turja et al. (2014), we suggest the implementation of immunotoxic biomarkers for the evaluation of ecosystem health. However, these should be accompanied by complementary endpoints of biological effects encompassing i.e., physiological, antioxidant and bioenergetic markers.

  9. Scenario analysis on protein consumption and climate change effects on riverine N export to the Baltic Sea.

    PubMed

    Eriksson Hägg, Hanna; Humborg, Christoph; Mörth, Carl-Magnus; Medina, Miguel Rodriguez; Wulff, Fredrik

    2010-04-01

    This paper evaluates possible future nitrogen loadings from 105 catchments surrounding the Baltic Sea. Multiple regressions are used to model total nitrogen (TN) flux as a function of specific runoff (Q), atmospheric nitrogen deposition, and primary emissions (PE) from humans and livestock. On average cattle contributed with 63%, humans with 20%, and pigs with 17% of the total nitrogen PE to land. Compared to the reference period (1992-1996) we then evaluated two types of scenarios for year 2070. i) An increased protein consumption scenario that led to 16% to 39% increased mean TN flux (kg per km(-2)). ii) Four climate scenarios addressing effects of changes in river discharge. These scenarios showed increased mean TN flux from the northern catchments draining into the Gulf of Bothnia (34%) and the Gulfs of Finland and Riga (14%), while the mean TN flux decreased (-27%) for catchments draining to the Baltic Proper. However, the net effect of the scenarios showed a possible increase in TN flux ranging from 3-72%. Overall an increased demand for animal protein will be instrumental for the Baltic Sea ecosystem and may be a major holdback to fulfill the environmental goals of the Baltic Sea Action Plan. PMID:20230019

  10. Sex-specific distribution and diet of Platichthys flesus at the end of spawning in the northern Baltic Sea.

    PubMed

    Borg, J P G; Westerbom, M; Lehtonen, H

    2014-04-01

    This study examined the relationship of seascape structure, prey availability and sex on the post-spawning distribution and diet of European flounder Platichthys flesus in the northern Baltic Sea. The objectives were to determine whether: (1) wave exposure and substratum affect abundance and distribution of P. flesus, (2) diet reflects the benthic prey composition and (3) sex affects the distribution or diet of P. flesus. The results showed that P. flesus was evenly spread in the archipelago with no correlation to wave exposure. The distribution was, however, sex specific; reproductive males dominated the exposed zone and mainly post-reproductive females dominated the intermediate and sheltered zones. Platichthys flesus fed mainly on two bivalve prey species: blue mussels Mytilus edulis and Baltic tellins Macoma balthica. Hard substratum invertebrates dominated the diet in all habitats and apart from some typical soft substratum species, there was no clear link between fish feeding and the dominance structure of benthic prey. Diet was further sex specific, with females showing a broader range of diet than males. Results suggest that P. flesus is a specialist molluscivore found commonly and equally in soft- and hard-substratum habitats throughout the archipelago area. Previous studies on P. flesus in the Baltic Sea have yielded inconsistent results regarding diet and it has commonly been believed that the distribution of Baltic Sea P. flesus is linked to sand and soft substrata. The present findings emphasize the importance of including the entire range of habitats when diet and regional species distributions are assessed.

  11. Groundfish overfishing, diatom decline, and the marine silica cycle: Lessons from Saanich Inlet, Canada, and the Baltic Sea cod crash

    NASA Astrophysics Data System (ADS)

    Katz, Timor; Yahel, Gitai; Yahel, Ruthy; Tunnicliffe, Verena; Herut, Barak; Snelgrove, Paul; Crusius, John; Lazar, Boaz

    2009-12-01

    In this study, we link groundfish activity to the marine silica cycle and suggest that the drastic mid-1980s crash of the Baltic Sea cod (Gadus morhua) population triggered a cascade of events leading to decrease in dissolved silica (DSi) and diatom abundance in the water. We suggest that this seemingly unrelated sequence of events was caused by a marked decline in sediment resuspension associated with reduced groundfish activity resulting from the cod crash. In a study in Saanich Inlet, British Columbia, Canada, we discovered that, by resuspending bottom sediments, groundfish triple DSi fluxes from the sediments and reduce silica accumulation therein. Using these findings and the available oceanographic and environmental data from the Baltic Sea, we estimate that overfishing and recruitment failure of Baltic cod reduced by 20% the DSi supply from bottom sediments to the surface water leading to a decline in the diatom population in the Baltic Sea. The major importance of the marginal ocean in the marine silica cycle and the associated high population density of groundfish suggest that groundfish play a major role in the silica cycle. We postulate that dwindling groundfish populations caused by anthropogenic perturbations, e.g., overfishing and bottom water anoxia, may cause shifts in marine phytoplankton communities.

  12. Dissolved organic phosphorus and its bioavailable fraction in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Nausch, M.; Nausch, G.; Setzkorn, D.; Welz, Ä.

    2009-04-01

    In general, it is accepted that dissolved organic phosphorus (DOP) is besides dissolved inorganic phosphorus (DIP) a source for phosphorus nutrition of phyto- and bacterioplankton. If available, DIP is usually preferred to DOP. DOP becomes the most important source under DIP depleted conditions occurring in the Baltic Sea in summer. However, its contribution to nutrition and consequently its significance is very difficult to appraise because only the bioavailable fraction (BAP = bioavailable phosphorus) can be used by organisms. DOP comprises also inert compounds which persist over longer periods. Therefore, there is an urgent need to quantify the bioavailable DOP. In 2004 and 2005, DOP and BAP concentrations were detected in surface water at three stations in the central Baltic Sea from May until July. In June/July 2008 an intensive measuring campaign was performed throughout the whole Baltic Sea. DOP measurements were done from the entrance to the North Sea in the West until the innermost parts of the Gulf of Bothnia in the North and the Gulf of Finland in the East. BAP was determined at 14 stations in the central and northern parts. DOP was determined using the alkaline potassium peroxidisulphate oxidation method followed by the manual DIP determination. BAP has been detected in time course experiments using 0.8 µm filtered sea water containing free-living heterotrophic bacteria and amended with 7 µM ammonium chloride and 1mg l-1 D-(+) glucosemonohydrate to prevent nitrogen and carbon limitation and increase the phosphorus demand in bacteria. BAP is defined as that proportion of DOP which is used by bacteria and calculated as the difference of DOP concentrations at the beginning and the lowest concentrations during an incubation for 4-6 days. In 2004 and 2005, most DOP concentrations ranged between 0.18 and 0.32 µM, with a declining tendency from spring to summer probably due to elevated uptake compared to its release caused by higher temperatures and DIP

  13. Qualitative and quantitative composition of microplastics particles during the expeditionary measurement program in the South-Eastern Baltic Sea

    NASA Astrophysics Data System (ADS)

    Esiukova, Elena; Bagaeva, Margarita; Chubarenko, Natalia

    2016-04-01

    According to the tasks of the Russian Science Foundation project "Physical and dynamical properties of marine microplastics particles and their transport in a basin with vertical and horizontal salinity gradient on the example of the Baltic Sea" number 15-17-10020, a comprehensive expeditionary program of measurements in the South-Eastern Baltic started. The project is aimed at finding solutions for a number of problems caused by superfluous plastic pollution in the World Ocean and, in particular, in the Baltic Sea. This pollution has been accumulating for years and just recently it has become obvious that only multidisciplinary approach (geographical, biological, chemical, etc.) to the issues related to the processes of transformation of properties and propagation of plastic particles will allow the study of physical aspects of the problem. During the first stage of the study samples should be selected from the water surface, water column at various horizons, bottom sediments in the Baltic Sea, from different areas at the beaches - in order to further examine the qualitative and quantitative composition of microplastic particles in different seasons for different hydrophysical situations. Reconnaissance survey was begun to choose the fields for research close to point and distributed sources of microplastics. Preference is given to those beaches that are exposed to maximum anthropogenic pollution: areas around the town of Baltiysk, the northern part of the Vistula Spit (near the settlement of Kosa), and the Sambia peninsula coast (settlements of Yantarny, Donskoye, Primorye, Kulikovo, towns of Svetlogorsk, Pionersky, Zelenogradsk). Locations for experimental sites were found in order to assess time for formation of microplastics (Vistula Spit, Kosa settlement). In June-November, 2015 there were 5 expeditions in the waters of the South-Eastern Baltic, 7 expeditions along the coast line of the Baltic Sea (in Kaliningrad Oblast), and 5 expeditions to the Vistula

  14. Anisakids of seals found on the southern coast of Baltic Sea.

    PubMed

    Skrzypczak, Michał; Rokicki, Jerzy; Pawliczka, Iwona; Najda, Katarzyna; Dzido, Joanna

    2014-03-01

    In the present study 5 grey seals (Halichoerus grypus), 3 common seals (Phoca vitulina) and 1 ringed seal (Pusa hispida) bycaught or stranded on the Polish Baltic Sea coast in years 2000-2006 were investigated for the infestation of parasitic anisakid nematodes. 749 of anisakids were found. The most common were: Contracaecum osculatum (59.3%) and Pseudoterranova decipiens (31.0%). There were also small numbers of Anisakis simplex (0.8%). After performing RFLP three sibling species were found. C. osculatum was identified as C. osculatum C, P decipiens was identified as P. decipiens sensu stricto and A. simplex - A. simplex sensu stricto. Nematodes found in seals were mostly in L4 and adult life stage - both of them were equal with some minor variations among the specimens. Sex ratio was also equal, but there was slight excess of males in some cases. There was a minority of L3 larvae belonging to A. simplex species (0.8%).

  15. Baltic Sea ecosystem-based management under climate change: Synthesis and future challenges.

    PubMed

    Blenckner, Thorsten; Österblom, Henrik; Larsson, Per; Andersson, Agneta; Elmgren, Ragnar

    2015-06-01

    Ecosystem-based management (EBM) has emerged as the generally agreed strategy for managing ecosystems, with humans as integral parts of the managed system. Human activities have substantial effects on marine ecosystems, through overfishing, eutrophication, toxic pollution, habitat destruction, and climate change. It is important to advance the scientific knowledge of the cumulative, integrative, and interacting effects of these diverse activities, to support effective implementation of EBM. Based on contributions to this special issue of AMBIO, we synthesize the scientific findings into four components: pollution and legal frameworks, ecosystem processes, scale-dependent effects, and innovative tools and methods. We conclude with challenges for the future, and identify the next steps needed for successful implementation of EBM in general and specifically for the Baltic Sea. PMID:26022332

  16. Certified Reference Material IAEA-446 for radionuclides in Baltic Sea seaweed.

    PubMed

    Pham, M K; Benmansour, M; Carvalho, F P; Chamizo, E; Degering, D; Engeler, C; Gascó, C; Gwynn, J P; Harms, A V; Hrnecek, E; Ibanez, F L; Ilchmann, C; Ikaheimonen, T; Kanisch, G; Kloster, M; Llaurado, M; Mauring, A; Møller, B; Morimoto, T; Nielsen, S P; Nies, H; Norrlid, L D R; Pettersson, H B L; Povinec, P P; Rieth, U; Samuelsson, C; Schikowski, J; Silobritiene, B V; Smedley, P A; Suplinska, M; Vartti, V-P; Vasileva, E; Wong, J; Zalewska, T; Zhou, W

    2014-05-01

    A Certified Reference Material (CRM) for radionuclides in seaweed (Fucus vesiculosus) from the Baltic Sea (IAEA-446) is described and the results of the certification process are presented. The (40)K, (137)Cs, (234)U and (239+240)Pu radionuclides were certified for this material, and information values for 12 other radionuclides ((90)Sr, (99)Tc, (210)Pb ((210)Po), (226)Ra, (228)Ra, (228)Th, (230)Th, (232)Th, (235)U, (238)U, (239)Pu and (240)Pu) are presented. The CRM can be used for Quality Assurance/Quality Control of analysis of radionuclides in seaweed and other biota samples, as well as for development and validation of analytical methods, and for training purposes.

  17. Subdivision of Holocene Baltic sea sediments by their physical properties [Gliederung holozaner ostseesedimente nach physikalischen Eigenschaften

    USGS Publications Warehouse

    Harff, Jan; Bohling, G.C.; Endler, R.; Davis, J.C.; Olea, R.A.

    1999-01-01

    The Holocene sediment sequence of a core taken within the centre of the Eastern Gotland Basin was subdivided into 12 lithostratigraphic units based on MSCL-data (sound velocity, wet bulk density, magnetic susceptibility) using a multivariate classification method. The lower 6 units embrace the sediments until the Litorina transgression, and the upper 6 units subdivide the brackish-marine Litorina- and post-Litorina sediments. The upper lithostratigraphic units reflect a change of anoxic (laminated) and oxic (non-laminated) sediments. By application of a numerical stratigraphic correlation method the zonation was extended laterally onto contiguous sediment cores within the central basin. Consequently the change of anoxic and oxic sediments can be used for a general lithostratigraphic subdivision of sediments of the Gotland Basin. A quantitative criterion based on the sediment-physical lithofacies is added to existing subdivisions of the Holocene in the Baltic Sea.

  18. Certified Reference Material IAEA-446 for radionuclides in Baltic Sea seaweed.

    PubMed

    Pham, M K; Benmansour, M; Carvalho, F P; Chamizo, E; Degering, D; Engeler, C; Gascó, C; Gwynn, J P; Harms, A V; Hrnecek, E; Ibanez, F L; Ilchmann, C; Ikaheimonen, T; Kanisch, G; Kloster, M; Llaurado, M; Mauring, A; Møller, B; Morimoto, T; Nielsen, S P; Nies, H; Norrlid, L D R; Pettersson, H B L; Povinec, P P; Rieth, U; Samuelsson, C; Schikowski, J; Silobritiene, B V; Smedley, P A; Suplinska, M; Vartti, V-P; Vasileva, E; Wong, J; Zalewska, T; Zhou, W

    2014-05-01

    A Certified Reference Material (CRM) for radionuclides in seaweed (Fucus vesiculosus) from the Baltic Sea (IAEA-446) is described and the results of the certification process are presented. The (40)K, (137)Cs, (234)U and (239+240)Pu radionuclides were certified for this material, and information values for 12 other radionuclides ((90)Sr, (99)Tc, (210)Pb ((210)Po), (226)Ra, (228)Ra, (228)Th, (230)Th, (232)Th, (235)U, (238)U, (239)Pu and (240)Pu) are presented. The CRM can be used for Quality Assurance/Quality Control of analysis of radionuclides in seaweed and other biota samples, as well as for development and validation of analytical methods, and for training purposes. PMID:24291528

  19. Condition of South-Eastern Baltic Sea Shores and Methods of Protecting Them

    NASA Astrophysics Data System (ADS)

    Ostrowski, Rafał; Pruszak, Zbigniew; Babakov, Alexander

    2014-06-01

    The paper describes lithodynamic and morphodynamic processes occurring in the main part of the south-eastern Baltic coastal area, namely on the sea shores from the Vistula mouth in the Gulf of Gdansk to the Lithuanian-Latvian border. The study area is subject to intensive natural coastal changes, as well as shore evolution caused by anthropogenic impacts at several locations. Methods of coastal protection against erosion and shore stabilization systems applied in the past and currently are described. The paper deals with the causes of the dynamics of beach/dune shores and cliffs. It presents the authors' field observations of 2010-2013, as well as previously gained knowledge and the results of Polish, Russian and joint Polish-Russian field surveys.

  20. Influence of water salinity on corrosion risk-the case of the southern Baltic Sea coast.

    PubMed

    Zakowski, K; Narozny, M; Szocinski, M; Darowicki, K

    2014-08-01

    Water corrosivity in Gdansk Bay, Poland, the southern part of the Baltic Sea, was investigated. The analysed region is heavily industrialized, and the coastline is very diverse. Twenty-seven test points along the coastline were selected. Water parameters such as salinity, total dissolved solids content, resistivity, conductivity, oxygenation, pH and corrosion rate were determined. The results of the investigation are presented. Water samples were collected, and structural steel specimens were exposed in the water for 2 months. The corrosion rate for each test point was determined and plotted on a map. The spatial distribution of water parameters was calculated using the 'inverse distance to a power' method and presented on the maps. Salinity did not exceed 0.7 %, and average corrosion rate equalled 0.0585 mm/year.

  1. Climate change in the Baltic sea region: a cross-country analysis of institutional stakeholder perceptions.

    PubMed

    Piwowarczyk, Joanna; Hansson, Anders; Hjerpe, Mattias; Chubarenko, Boris; Karmanov, Konstantin

    2012-09-01

    Before climate change is considered in long-term coastal management, it is necessary to investigate how institutional stakeholders in coastal management conceptualize climate change, as their awareness will ultimately affect their actions. Using questionnaires in eight Baltic Sea riparian countries, this study examines environmental managers' awareness of climate change. Our results indicate that problems related to global warming are deemed secondary to short-term social and economic issues. Respondents agree that problems caused by global warming will become increasingly important, but pay little attention to adaptation and mitigation strategies. Current environmental problems are expected to continue to be urgent in the future. We conclude that an apparent gap exists between decision making, public concerns, and scientific consensus, resulting in a situation in which the latest evidence rarely influences commonly held opinions. PMID:22926886

  2. Even low to medium nitrogen deposition impacts vegetation of dry, coastal dunes around the Baltic Sea.

    PubMed

    Remke, Eva; Brouwer, Emiel; Kooijman, Annemieke; Blindow, Irmgard; Esselink, Hans; Roelofs, Jan G M

    2009-03-01

    Coastal dunes around the Baltic Sea have received small amounts of atmospheric nitrogen and are rather pristine ecosystems in this respect. In 19 investigated dune sites the atmospheric wet nitrogen deposition is 3-8kg Nha(-1)yr(-1). The nitrogen content of Cladonia portentosa appeared to be a suitable biomonitor of these low to medium deposition levels. Comparison with EMEP-deposition data showed that Cladonia reflects the deposition history of the last 3-6 years. With increasing nitrogen load, we observed a shift from lichen-rich short grass vegetation towards species-poor vegetation dominated by the tall graminoid Carex arenaria. Plant species richness per field site, however, does not decrease directly with these low to medium N deposition loads, but with change in vegetation composition. Critical loads for acidic, dry coastal dunes might be lower than previously thought, in the range of 4-6kg Nha(-1)yr(-1) wet deposition.

  3. Macroalgal diversity along the Baltic Sea salinity gradient challenges Remane's species-minimum concept.

    PubMed

    Schubert, Hendrik; Feuerpfeil, Peter; Marquardt, Ronny; Telesh, Irena; Skarlato, Sergei

    2011-09-01

    Remane's species-minimum concept, which states that the lowest number of taxa occurs at the horohalinicum (5-8psu), was tested by investigating macroalgal diversity on hard substrates along the natural salinity gradient in the Baltic Sea. Field data on species occurrence and abundance were collected by SCUBA diving along 10 transects of the Finnish, Swedish and German coasts, covering a salinity range from 3.9 to 27psu. Macroalgal species numbers declined steadily with salinity, decreasing until 7.2psu was reached, but in the horohalinicum, a marked reduction of species number and a change in diversity were indicated by the Shannon index and evenness values. The non-linear decrease in macroalgal diversity at 5-8psu and the lack of increase in species numbers at salinities below 5psu imply a restricted applicability of Remane's species-minimum concept to macroalgae.

  4. Legal prerequisites for ecosystem-based management in the Baltic Sea area: The example of eutrophication.

    PubMed

    Nilsson, Annika K; Bohman, Brita

    2015-06-01

    The purpose of this paper is to discuss the role of law in the management of the Baltic Sea, with focus on eutrophication. It aims to identify legal instruments or structures realizing an ecosystem approach. This also includes a discussion of the prerequisites of law as contributor to ecosystem-based management (EBM), as well as evaluation of current legal instruments. While ecosystem approach to environmental management is central to contemporary environmental management policy, it is still unclear what such an approach entails in concrete legal terms. The scope of the analysis stretches from international and EU legal regimes, to implementation and regulation within the national legal systems. A conclusion is that the management structures need further development to properly realize EBM, for example, through concretization of management measures, and clarification of duties and responsibilities for their realization.

  5. Baltic Sea ecosystem-based management under climate change: Synthesis and future challenges.

    PubMed

    Blenckner, Thorsten; Österblom, Henrik; Larsson, Per; Andersson, Agneta; Elmgren, Ragnar

    2015-06-01

    Ecosystem-based management (EBM) has emerged as the generally agreed strategy for managing ecosystems, with humans as integral parts of the managed system. Human activities have substantial effects on marine ecosystems, through overfishing, eutrophication, toxic pollution, habitat destruction, and climate change. It is important to advance the scientific knowledge of the cumulative, integrative, and interacting effects of these diverse activities, to support effective implementation of EBM. Based on contributions to this special issue of AMBIO, we synthesize the scientific findings into four components: pollution and legal frameworks, ecosystem processes, scale-dependent effects, and innovative tools and methods. We conclude with challenges for the future, and identify the next steps needed for successful implementation of EBM in general and specifically for the Baltic Sea.

  6. Nitrification rates in the baltic sea: comparison of three isotope techniques.

    PubMed

    Enoksson, V

    1986-02-01

    Simultaneous measurements of nitrification in the Baltic Sea were made at 10- to 30-m intervals in the months of June and November by three isotope techniques: [N]nitrate dilution, N-serve sensitive [C]bicarbonate incorporation, and [N]ammonium oxidation to nitrite and nitrate. Nitrification rates of 1 to 280 nmol liter day were recorded, and each method showed that the highest rates of nitrification occurred below the halocline. Even in the presence of ammonium, dark incubations of mixed layer (above ca. 50 m) waters never yielded nitrification rates exceeding 45 nmol liter day. The rates measured by the ammonium oxidation method were two- to sevenfold greater than those obtained by C incorporation or N dilution. The merits of each technique are discussed, and it is suggested that the [N]ammonium oxidation method should be used in conjunction with the [C]bicarbonate incorporation method. PMID:16346982

  7. Modeling the Role of pH on Baltic Sea Cyanobacteria

    PubMed Central

    Hinners, Jana; Hofmeister, Richard; Hense, Inga

    2015-01-01

    We simulate pH-dependent growth of cyanobacteria with an ecosystem model for the central Baltic Sea. Four model components—a life cycle model of cyanobacteria, a biogeochemical model, a carbonate chemistry model and a water column model—are coupled via the framework for aquatic biogeochemical models. The coupled model is forced by the output of a regional climate model, based on the A1B emission scenario. With this coupled model, we perform simulations for the period 1968–2098. Our simulation experiments suggest that in the future, cyanobacteria growth is hardly affected by the projected pH decrease. However, in the simulation phase prior to 1980, cyanobacteria growth and N2-fixation are limited by the relatively high pH. The observed absence of cyanobacteria before the 1960s may thus be explained not only by lower eutrophication levels, but also by a higher alkalinity. PMID:25830591

  8. Scenario simulations of future salinity and ecological consequences in the Baltic Sea and adjacent North Sea areas–implications for environmental monitoring

    PubMed Central

    Vuorinen, Ilppo; Hänninen, Jari; Rajasilta, Marjut; Laine, Päivi; Eklund, Jan; Montesino-Pouzols, Federico; Corona, Francesco; Junker, Karin; Meier, H.E.Markus; Dippner, Joachim W.

    2015-01-01

    Substantial ecological changes occurred in the 1970s in the Northern Baltic during a temporary period of low salinity (S). This period was preceded by an episodic increase in the rainfall over the Baltic Sea watershed area. Several climate models, both global and regional, project an increase in the runoff of the Northern latitudes due to proceeding climate change. The aim of this study is to model, firstly, the effects on Baltic Sea salinity of increased runoff due to projected global change and, secondly, the effects of salinity change on the distribution of marine species. The results suggest a critical shift in the S range 5–7, which is a threshold for both freshwater and marine species distributions and diversity. We discuss several topics emphasizing future monitoring, modelling, and fisheries research. Environmental monitoring and modelling are investigated because the developing alternative ecosystems do not necessarily show the same relations to environment quality factors as the retiring ones. An important corollary is that the observed and modelled S changes considered together with species’ ranges indicate what may appear under a future climate. Consequences could include a shift in distribution areas of marine benthic foundation species and some 40–50 other species, affiliated to these. This change would extend over hundreds of kilometres, in the Baltic Sea and the adjacent North Sea areas. Potential cascading effects, in coastal ecology, fish ecology and fisheries would be extensive, and point out the necessity to develop further the “ecosystem approach in the environmental monitoring”. PMID:25737660

  9. A Comparison of Eemian and Holocene Transgressions of the Baltic Sea based on the Sedimentary Record of Lake Ladoga

    NASA Astrophysics Data System (ADS)

    Delusina, I.; Andreev, A.

    2015-12-01

    Two cycles of postglacial transgressions of Baltic Sea could be recognized in the sediments of Lake Ladoga and vicinity: an Eemian (MIS 5e, ca 124-119 kya) and a Holocene with several subsequent stages: Ancylus Lake, Mastogloia Sea and Littorina Sea, starting at ca 9.5 kya BP and existing up to 4 kya BP. New data obtained from deep coring in Lake Ladoga (Andreev et al., 2014) has allowed us to re-visit an old question about the age and nature of sediments at the bottom of Lake Ladoga. The lake is east of the Baltic and provides important information about the marginal stage of Baltic Sea levels, and in particular about differences between the Eemian and Holocene transgressions. Previously Eemian marine sediments have never been found at the bottom of Lake Ladoga although they have been identified along river terraces, in small lakes and as detached lenses. The new coring reached a depth of 22 m, and found marine diatoms that might correspond to the Eemian transgression. As part of the effort to understand these fossils, we have compiled a comprehensive picture of the distribution of Eemian sediments around Lake Ladoga. There is very little published data about these deposits (Miettinen et al., 2014) so we have assembled known, but never published or published only in Russian, data. The number of unpublished marine Eemian sequences exceeds 70. They occur more frequently here than on other Baltic coasts, because of the low position of the eastern Baltic territories above the sea level. This meant that they were not destroyed by isostatic uplift, which resulted in the deposition of thicker layers of sediment than in mountainous Fennoscandia. Typical Eemian sediments comprise a black clay layer with Yoldia arctica, have a monotonous appearance and are easily distinguished from other interglacial sediments. The modern elevation of these sections implies that the elevation of the Eemian Sea could not have exceeded +17 m and probably was very uniform.The Holocene

  10. The Anomalously High Pole Tide in the North and Baltic Seas Estimated by the PSMSL Tide Gauge Data

    NASA Astrophysics Data System (ADS)

    Medvedev, Igor; Rabinovich, Alexander; Kulikov, Evgueni

    2014-05-01

    Pole tide driven by the Chandler wobble, has the period of about 14 months and typical amplitudes in the World Ocean of ~ 0.5 cm. However, in the North and Baltic Seas they are anomalously high. To examine this effect we used long monthly sea level records from 80 stations with the length up to 212 years. High-resolution spectra revealed a cluster of neighboring peaks with periods from 410 to 440 days. The results of spectral analysis were applied to estimate the integral amplitudes of pole tides from all available tide gauges along the coast of seas. The height of the pole tide was found to gradually increase from the entrance of the Baltic Sea (Danish Straits) to the northeast end of the Baltic Sea. The largest amplitudes - up to 4.5-7 cm - were observed in the heads of the Gulf of Finland and the Gulf of Bothnia. Significant temporal fluctuations in amplitudes and periods of the pole tide were observed during XIX and XX centuries.

  11. Linkage between acoustic parameters and seabed sediment properties in the south-western Baltic Sea

    NASA Astrophysics Data System (ADS)

    Endler, Michael; Endler, Rudolf; Bobertz, Bernd; Leipe, Thomas; Arz, Helge W.

    2015-04-01

    Acoustic profiling methods are widely used to provide a rapid view into geological structures. For the interpretation of acoustic profiling results (single- and multi-beam), reliable geo-acoustic models are needed. Suitable geo-acoustic models covering a wide range of sediment types do not exist to date for the Baltic Sea. Based on surface sediment datasets, geo-acoustic models have been set up for the prediction of acoustical parameters derived from sedimentological data for south-western Baltic Sea surface sediments. Empirical relationships were created to predict key in situ parameters (p-wave velocity, wet bulk density) from sedimentological core data, notably grain density and water content. The Gassmann-Hamilton equations were used to set up a more generic physically based model. For the first time semi-empirical equations for the calculation of the elastic frame modulus and the solid sediment particle modulus were established by an iterative Gassmann-Hamilton fitting procedure. The resulting models have a remarkably good performance with, for example, a calculated sound velocity accuracy of about 17-32 m s-1 depending on model input data. The acoustic impedance of seafloor sediments can be estimated from single-beam echosounding if the contribution of seafloor reflectivity is extracted from the total acoustic signal. The data reveal a strong linkage between acoustic impedance and selected sediment properties (e.g. grain size, water content). This underlines the potential for effective mapping of seafloor sediment properties (e.g. habitat mapping). Furthermore, these geo-acoustic models can be used by marine geologists for a precise linkage between sediment facies identified in longer cores and corresponding acoustic facies recorded by high-resolution seismic profiling in future work.

  12. Dimethyl sulfide in the Baltic Sea: Annual variability in relation to biological activity

    SciTech Connect

    Leck, C.; Larsson, U.; Bagander, L.E.; Johansson, S.; Hajdu, S. )

    1990-03-15

    The in situ variation of dimethyl sulfide (CH{sub 3}SCH{sub 3}, DMS) at a fixed station in a coastal area of the Baltic Sea has been studied for a period of time (January 1987 to June 1988) covering the annual biological cycle. DMS in the surface waters of the brackish Baltic Sea showed a clear seasonal variation, ranging from 2 to 200 ng S/l. Lowest concentrations were in winter, peak values followed the spring bloom, and a pronounced maximum was found during the summer. Concentrations above low winter levels occurred only when the trophogenic layer was depleted of inorganic nitrogen. From data it is clear that the seasonal variation in DMS concentration is related to biological activity. However, the authors did not find any correlations between DMS concentration and gross parameters such as chlorophyll a, total phytoplankton biomass, or primary production on an annual basis. Further, they were not able to relate high DMS concentrations to any particular phytoplankton species or species assemblages. It appears that DMS production is primarily associated with phytoplankton growth under nitrogen-limited conditions and not with certain species. The authors found a significant correlation of ambient DMS concentration with copepod and total zooplankton biomass, suggesting zooplankton grazing pressure as the major factor responsible for the liberation of {beta}-dimethylsulfoniopropionate (DMSP) from phytoplankton cells and thus for the DMS production. The turnover time of DMS in the water column was calculated to be of the order of 2 days, and the most effective sink process seems to be microbiological and/or chemical origin.

  13. Cultivation and diversity of fungi buried in the Baltic Sea sediments

    NASA Astrophysics Data System (ADS)

    Xiao, N.

    2015-12-01

    @font-face { "MS 明朝"; }@font-face { "Century"; }@font-face { "Century"; }@font-face { "@MS 明朝"; }p.MsoNormal, li.MsoNormal, div.MsoNormal { margin: 0mm 0mm 0.0001pt; text-align: justify; font-size: 12pt; ; }.MsoChpDefault { ; }div.WordSection1 { page: WordSection1; } Studies on molecular biological and cultivation have been done for the prokaryotic microbial community in the deep biosphere. Compare to the prokaryotic community, few attempts have been done for eukaryotic microbial community. Here we report the study on fungi buried in deep-subsurface sediments by approaches of both cultivation and molecular diversity survey. Cultivation targeting fungi has been done using a sequential sediment samples obtained from the Baltic Sea, Landsort Deep site during the IODP expedition 347. 6 culture media with different nutrition and salt concentration have been tried for the fungi cultivation. 50 isolates of fungi were obtained from the sediment samples. The surface sediments showed richness of fungi strains but not for the deep sediments. Internal Transcribed Spacer (ITS) regions of RNA genes were amplified and for the identification of the isolates. The isolates were classified to 11 different genera. Pseudeurotium bakeri was the dominant strain throughout the glacial and interglacial sediments. We also found different representative fungal strains from glacial and interglacial sediments, suggesting the cultivated strains are buried from different sources. The survey of fungal diversity was done by sequencing the 18S RNA genes in the total DNA extracted from selected sediment samples. Fungi community showed different cluster in the glacial and interglacial sediments.Our results revealed the presence and activity of fungi in the deep biosphere of the Baltic sea and provided evidence of fungal community response to the climate change.

  14. Unveiling Trophic Functions of Uncultured Protist Taxa by Incubation Experiments in the Brackish Baltic Sea

    PubMed Central

    Weber, Felix; del Campo, Javier; Wylezich, Claudia; Massana, Ramon; Jürgens, Klaus

    2012-01-01

    Abstract Background Our knowledge of the phylogeny and diversity of aquatic protists is rapidly increasing due to molecular surveys and next-generation sequencing approaches. This has led to a considerable discrepancy between the taxa known from cultures and those known from environmental 18S rRNA gene sequences. Hence, it is generally difficult to assign ecological functions to new taxa detected by culture-independent molecular approaches. Methodology/Principal Findings A combination of unamended dark incubations and 18S rRNA sequencing was chosen to link molecular diversity data of uncultured protists with heterotrophic, presumably bacterivorous, growth. The incubations, conducted with Baltic Sea brackish water, resulted in a consistent shift from a protistan community dominated by phototrophs to one in which heterotrophs predominated. This was determined on the basis of cell abundance and 18S rRNA sequences derived from fingerprint analysis and clone libraries. The bulk of enriched phylotypes after incubation were related to hitherto uncultured marine taxa within chrysophytes, ochrophytes, choanoflagellates, cercozoans, and picobiliphytes, mostly represented in recently established or here defined environmental clades. Their growth in the dark, together with coinciding results from studies with a similar objective, provides evidence that these uncultured taxa represent heterotrophic or mixotrophic species. Conclusions/Significance These findings shed some light into the trophic role of diverse uncultured protists especially within functionally heterogeneous groups (e.g., chrysophytes, ochrophytes) and groups that appear to be puzzling with regard to their nutrition (picobiliphytes). Additionally, our results indicate that the heterotrophic flagellate community in the southwestern Baltic Sea is dominated by species of marine origin. The combination of unamended incubations with molecular diversity analysis is thus confirmed as a promising approach to explore the

  15. A multiprocessor coupled ice-ocean model for the Baltic Sea: Application to salt inflow

    NASA Astrophysics Data System (ADS)

    Meier, H. E. Markus; DöScher, Ralf; FaxéN, Torgny

    2003-08-01

    Within the Swedish Regional Climate Modeling Program, SWECLIM, a three-dimensional (3-D) coupled ice-ocean model for the Baltic Sea has been developed to simulate physical processes on timescales of hours to decades. The code has been developed based on the massively parallel version of the Ocean Circulation Climate Advanced Modeling (OCCAM) project of the Bryan-Cox-Semtner model. An elastic-viscous-plastic ice rheology is employed, resulting in a fully explicit numerical scheme that improves computational efficiency. An improved two-equation turbulence model has been embedded to simulate the seasonal cycle of surface mixed layer depths as well as deepwater mixing on decadal timescale. The model has open boundaries in the northern Kattegat and is forced with realistic atmospheric fields and river runoff. Optimized computational performance and advanced algorithms to calculate processor maps make the code fast and suitable for multi-year, high-resolution simulations. As test cases, the major salt water inflow event in January 1993 and the stagnation period 1980-1992, have been selected. The agreement between model results and observations is regarded as good. Especially, the time evolution of the halocline in the Baltic proper is realistically simulated also for the longer period without flux correction, data assimilation, or reinitialization. However, in particular, smaller salt water inflows into the Bornholm Basin are underestimated, independent of the horizontal model resolution used. It is suggested that the mixing parameterization still needs improvements. In addition, a series of process studies of the inflow period 1992/1993 have been performed to show the impact of river runoff, wind speed, and sea level in Kattegat. Natural interannual runoff variations control salt water inflows into the Bornholm Basin effectively. The effect of wind speed variation on the salt water flux from the Arkona Basin to the Bornholm Basin is minor.

  16. On The Heat and Salt Exchange Between The Deep Basins of The Baltic Sea

    NASA Astrophysics Data System (ADS)

    Lehmann, A.; Hinrichsen, H.-H.

    Fluxes of volume, heat and salt have been calculated from numerical model simula- tions for different sections in areas which are important for the deep water exchange in the Baltic Sea. The calculated deep water flow in the Arkona basin is in accordance with independent estimations obtained from profile data. It is found that the strength of the upper layer low saline flow in the Arkona Basin which is on average directed to the west, opposite to the mean wind direction, is compensated by a highly saline flow in deeper layers. Increasing upper layer flow will result in an increased lower layer flow in opposite direction indicating a baroclinic control. The annual mean flow is negatively correlated with the annual mean runoff to the Baltic Sea. In accordance to the mean circulation, the flow through the Bornholm Gat is on average directed to the east, and south of Bornholm the flow is directed to the west indicating an import of heat and salt to the Bornholm Basin through the Bornholm Gat and an export south of Bornholm. Flux characteristics change further downstream in the Stolpe Trench. The volume flow in the upper layer shows a strong seasonal signal. During autumn to spring the flow is mainly directed to the east, in summer the flow direction is reversed. Flow in westerly directions is related to increased lower layer flow in easterly direc- tions. On average the net flow through the Stolpe channel is directed to the east which is in accordance with the mean circulation. The calculated fluxes show high intra- and interannual variability with no obvious trend during the simulation period.

  17. Effects of fluvial discharges on meiobenthic and macrobenthic variability in the Vistula River prodelta (Baltic Sea)

    NASA Astrophysics Data System (ADS)

    Włodarska-Kowalczuk, Maria; Mazurkiewicz, Mikołaj; Jankowska, Emilia; Kotwicki, Lech; Damrat, Mateusz; Zajączkowski, Marek

    2016-05-01

    The role of environmental variability produced by river discharges in shaping the spatial and seasonal patterns of meiobenthic and macrobenthic communities was studied in the Vistula River (Baltic Sea) prodelta. Seven stations located in the delta front, the plume influence area and the distal zone of the prodelta were visited over the four seasons of 2012. Meiofauna, macrofauna, water (temperature, salinity, and suspended matter) and sediments (grain size, POC, TN, δ15N and δ13C and photosynthetic pigments) were analysed. The seasonal variations in the river discharges (with maximum flows in spring) resulted in a strong temporal variability in the studied environmental characteristics. In the benthic biota, the signals of seasonal variability, if present, were much weaker than spatial zonation. The benthic communities inhabiting the delta front where the main bulk of fluvial materials was deposited were taxonomically impoverished. The richest fauna dwelled within the plume influence area where the physical disturbance ceased and primary marine production was enhanced by river transported nutrients. In the distal zone outside the river influence, the fauna was dominated by deeper dwelling species, and the numbers of individuals and taxa decreased. Factors related to the riverine discharges (i.e., salinity, mineral suspension, POC and δ13C in the water and sediments) were identified as having high correlation with variability in the meiofaunal and macrofaunal community descriptors. Evidently, the interplay of food (i.e., the quantity and quality of organic matter) and disturbance (i.e., the deposition of river transported minerals) constraints shaped the patterns of benthic variability in the prodelta of the second largest river entering the Baltic Sea.

  18. The occurrence and depth penetration of macroalgae along environmental gradients in the northern Baltic Sea

    NASA Astrophysics Data System (ADS)

    Rinne, Henna; Salovius-Laurén, Sonja; Mattila, Johanna

    2011-08-01

    Eutrophication is known to affect the community structure of macroalgae by e.g. decreasing the depth penetration of species and by shifting dominance from perennial to annual species. However, there is substantial lack of knowledge in the Baltic Sea regarding the distribution of many of the macroalgal species, how natural environmental factors affect their occurrence and how they respond to eutrophication. As macroalgae are used as indicators of the quality of the sea areas in the EU legislation (Water Framework Directive, Marine Strategy Framework Directive), this kind of knowledge is essential. The aim of this study was to determine which variables were related to variation in species occurrence and their lower limit of occurrence in the Finnish marine area. The study was carried out on data from five study areas along the Finnish coastline and included about 30 taxa. Our results showed that both the macroalgal communities and the occurrence (presence/absence) of most of the species differed between the study areas and that the differences were mainly related to salinity and exposure, although also eutrophication related factors played a role. Of the perennial species, eutrophied conditions seemed to favour only the occurrence of Sphacelaria arctica and Polysiphonia fucoides. Secchi depth was important in determining the lower limit of occurrence of brown and red algal species. However, Secchi depth was rarely the only factor causing variation in the lower limit of occurrence as also exposure, salinity and slope of the shore affected it. We conclude that in the northern Baltic Sea, the taxonomic composition of the macroalgal communities is not a very useful indicator of eutrophication as perennial species seem to tolerate rather eutrophied conditions, when suitable substrate is available. The lower limit of occurrence of many of the brown and red algal species is a good indicator of eutrophication but due to lack of suitable substrate in more eutrophied areas

  19. Validation of multi-mission satellite altimetry for the Baltic Sea region

    NASA Astrophysics Data System (ADS)

    Kudryavtseva, Nadia; Soomere, Tarmo; Giudici, Andrea

    2016-04-01

    Currently, three sources of wave data are available for the research community, namely, buoys, modelling, and satellite altimetry. The buoy measurements provide high-quality time series of wave properties but they are deployed only in a few locations. Wave modelling covers large domains and provides good results for the open sea conditions. However, the limitation of modelling is that the results are dependent on wind quality and assumptions put into the model. Satellite altimetry in many occasions provides homogeneous data over large sea areas with an appreciable spatial and temporal resolution. The use of satellite altimetry is problematic in coastal areas and partially ice-covered water bodies. These limitations can be circumvented by careful analysis of the geometry of the basin, ice conditions and spatial coverage of each altimetry snapshot. In this poster, for the first time, we discuss a validation of 30 years of multi-mission altimetry covering the whole Baltic Sea. We analysed data from RADS database (Scharroo et al. 2013) which span from 1985 to 2015. To assess the limitations of the satellite altimeter data quality, the data were cross-matched with available wave measurements from buoys of the Swedish Meteorological and Hydrological Institute and Finnish Meteorological Institute. The altimeter-measured significant wave heights showed a very good correspondence with the wave buoys. We show that the data with backscatter coefficients more than 13.5 and high errors in significant wave heights and range should be excluded. We also examined the effect of ice cover and distance from the land on satellite altimetry measurements. The analysis of cross-matches between the satellite altimetry data and buoys' measurements shows that the data are only corrupted in the nearshore domain within 0.2 degrees from the coast. The statistical analysis showed a significant decrease in wave heights for sea areas with ice concentration more than 30 percent. We also checked and

  20. Diatom stratigraphy and long-term dissolved silica concentrations in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Olli, Kalle; Clarke, Annemarie; Danielsson, Åsa; Aigars, Juris; Conley, Daniel J.; Tamminen, Timo

    2008-10-01

    In many parts of the world coastal waters with anthropogenic eutrophication have experienced a gradual depletion of dissolved silica (DSi) stocks. This could put pressure on spring bloom diatom populations, e.g. by limiting the intensity of blooms or by causing shifts in species composition. In addition, eutrophication driven enhanced diatom growth is responsible for the redistribution of DSi from the water phase to the sediments, and changes in the growth conditions may be reflected in the sediment diatom stratigraphy. To test for changes in diatom communities we have analyzed four sediment cores from the Baltic Sea covering approximately the last 100 years. The sediment cores originate from the western Gulf of Finland, the Kattegat, the Baltic Proper and the Gulf of Riga. Three out of the four cores reveal only minor changes in composition of diatom assemblages, while the Gulf of Riga core contains major changes, occurring after the second World War. This area is set apart from the other Baltic Sea basins by a high frequency of low after spring bloom DSi concentrations (< 2 µmol L - 1 ) during a relatively well defined time period from 1991-1998. In 1991 to 1993 a rapid decline of DSi spring concentrations and winter stocks (down to 5 µmol L - 1 ) in the Gulf was preceded by exceptionally intense diatom spring blooms dominated by the heavily silicified species Thalassiosira baltica (1991-1992; up to 5.5 mg ww L - 1 ). T. baltica has been the principal spring bloom diatom in the Gulf of Riga since records began in 1975. DSi consumption and biomass yield experiments with cultured T. baltica suggest that intense blooms can potentially exhaust the DSi stock of the water column and exceed the annual Si dissolution in the Gulf of Riga. The phytoplankton time series reveals another exceptional T. baltica bloom period in 1981-1983 (up to 8 mg L - 1 ), which, however, took place before the regular DSi measurements. These periods may be reflected in the conspicuous

  1. Spatial and temporal habitat partitioning by zooplankton in the Bornholm Basin (central Baltic Sea)

    NASA Astrophysics Data System (ADS)

    Schulz, Jan; Peck, Myron A.; Barz, Kristina; Schmidt, Jörn Oliver; Hansen, Frank C.; Peters, Janna; Renz, Jasmin; Dickmann, Miriam; Mohrholz, Volker; Dutz, Jörg; Hirche, Hans-Jürgen

    2012-12-01

    The deep basins in the Baltic Sea such as the Bornholm Basin (BB) are subject to seasonal changes in the strength of physico-chemical stratification. These depth-related changes in key abiotic factors are strong drivers of habitat partitioning by the autochthonous zooplankton community. Species-specific ecophysiological preferences often result in both seasonal and inter-annual changes in vertical abundance that, when combined with depth-specific water currents, also lead to horizontal differences in spatial distribution. The present study documented the seasonal and depth-specific changes in the abundance and species composition of zooplankton in the BB based upon broad-scale survey data: 832 vertically-resolved (10 m) multinet samples collected at nine stations between March 2002 and May 2003. Changes in the zooplankton community were significantly correlated with changes in ambient hydrography. Each of five taxa (Bosmina coregoni maritima, Acartia spp., Pseudocalanus spp., Temora longicornis, Synchaeta spp.) contributed >10% to the zooplankton community composition. The appearance of cladocerans was mainly correlated with the phenology of thermocline development in the spring. The cladoceran B. coregoni maritima was a dominant member of this community during the warmest periods, preferring the surface waters above the thermocline. Copepods exhibited distinct, ontogenetic and seasonal changes in their distribution. The rotifers (Synchaeta sp.) were the most abundant zooplankton in May. Based on a multivariate approach and the evaluation of vertical distribution patterns, five major habitat utilisation modes were identified that were based, to a large extent, on the dynamics of thermal and haline stratification of the Baltic Sea. Our statistical analysis of one of the most thorough datasets collected on Baltic zooplankton in recent decades reveals some of the factors that make this stratified system highly dynamic with respect to the spatial overlap between

  2. (90)Sr in fish from the southern Baltic Sea, coastal lagoons and freshwater lake.

    PubMed

    Zalewska, Tamara; Saniewski, Michał; Suplińska, Maria; Rubel, Barbara

    2016-07-01

    Activity concentrations of radioactive (90)Sr were studied in four fish species: herring, flounder, sprat and cod caught in the southern Baltic Sea in two periods: 2005-2009 and 2013-2014. The study included also perch from the coastal lagoons - Vistula Lagoon and Szczcin Lagoon and a freshwater lake - Żarnowieckie Lake as well as additional lake species: pike and bream. (90)Sr activity concentrations were compared in relation to species and to particular tissue: muscle, whole fish (eviscerated) and bones. In 2014, in the Baltic, the maximal (90)Sr concentrations were found in fishbones: herring - 0.39 Bq kg(-1) w.w., cod - 0.48 Bq kg(-1) w.w., and flounder - 0.54 Bq kg(-1) w.w. In the whole fish the maximal concentrations were found in flounder - 0.16 Bq kg(-1) w.w. and cod - 0.15 Bq kg(-1) w.w., while in herring - 0.022 Bq kg(-1) w.w. and sprat - 0.026 Bq kg(-1) w.w. they stayed at lower level. Relatively high (90)Sr concentrations were detected in whole fish from freshwater Lake Żarnowieckie: perch - 0.054 Bq kg(-1) w.w., pike - 0.062 Bq kg(-1) w.w. and bream - 0.140 Bq kg(-1) w.w. Concentration ratio (CR) determined for particular fish tissues and for whole eviscerated fish in relation to (90)Sr concentrations in seawater and lake water were showing significant variability unlike the corresponding (137)Cs concentration ratios which are stable and specific for fish species. The study corroborates with the conviction of the growing role of (90)Sr in the overall radioactivity in the southern Baltic Sea as compared to (137)Cs. PMID:27061778

  3. (90)Sr in fish from the southern Baltic Sea, coastal lagoons and freshwater lake.

    PubMed

    Zalewska, Tamara; Saniewski, Michał; Suplińska, Maria; Rubel, Barbara

    2016-07-01

    Activity concentrations of radioactive (90)Sr were studied in four fish species: herring, flounder, sprat and cod caught in the southern Baltic Sea in two periods: 2005-2009 and 2013-2014. The study included also perch from the coastal lagoons - Vistula Lagoon and Szczcin Lagoon and a freshwater lake - Żarnowieckie Lake as well as additional lake species: pike and bream. (90)Sr activity concentrations were compared in relation to species and to particular tissue: muscle, whole fish (eviscerated) and bones. In 2014, in the Baltic, the maximal (90)Sr concentrations were found in fishbones: herring - 0.39 Bq kg(-1) w.w., cod - 0.48 Bq kg(-1) w.w., and flounder - 0.54 Bq kg(-1) w.w. In the whole fish the maximal concentrations were found in flounder - 0.16 Bq kg(-1) w.w. and cod - 0.15 Bq kg(-1) w.w., while in herring - 0.022 Bq kg(-1) w.w. and sprat - 0.026 Bq kg(-1) w.w. they stayed at lower level. Relatively high (90)Sr concentrations were detected in whole fish from freshwater Lake Żarnowieckie: perch - 0.054 Bq kg(-1) w.w., pike - 0.062 Bq kg(-1) w.w. and bream - 0.140 Bq kg(-1) w.w. Concentration ratio (CR) determined for particular fish tissues and for whole eviscerated fish in relation to (90)Sr concentrations in seawater and lake water were showing significant variability unlike the corresponding (137)Cs concentration ratios which are stable and specific for fish species. The study corroborates with the conviction of the growing role of (90)Sr in the overall radioactivity in the southern Baltic Sea as compared to (137)Cs.

  4. Bacteriohopanepolyols record stratification, nitrogen fixation and other biogeochemical perturbations in Holocene sediments of the central Baltic Sea

    NASA Astrophysics Data System (ADS)

    Blumenberg, M.; Berndmeyer, C.; Moros, M.; Muschalla, M.; Schmale, O.; Thiel, V.

    2013-04-01

    The Baltic Sea, one of the world's largest brackish-marine basins, established after deglaciation of Scandinavia about 17 000 to 15 000 yr ago. In the changeable history of the Baltic Sea, the initial freshwater system was connected to the North Sea about 8000 yr ago and the modern brackish-marine setting (Littorina Sea) was established. Today, a relatively stable stratification has developed in the water column of the deep basins due to salinity differences. Stratification is only occasionally interrupted by mixing events, and it controls nutrient availability and growth of specifically adapted microorganisms and algae. We studied bacteriohopanepolyols (BHPs), lipids of specific bacterial groups, in a sediment core from the central Baltic Sea (Gotland Deep) and found considerable differences between the distinct stages of the Baltic Sea's history. Some individual BHP structures indicate contributions from as yet unknown redoxcline-specific bacteria (bacteriohopanetetrol isomer), methanotrophic bacteria (35-aminobacteriohopanetetrol), cyanobacteria (bacteriohopanetetrol cyclitol ether isomer) and from soil bacteria (adenosylhopane) through allochthonous input after the Littorina transgression, whereas the origin of other BHPs in the core has still to be identified. Notably high BHP abundances were observed in the deposits of the brackish-marine Littorina phase, particularly in laminated sediment layers. Because these sediments record periods of stable water column stratification, bacteria specifically adapted to these conditions may account for the high portions of BHPs. An additional and/or accompanying source may be nitrogen-fixing (cyano)bacteria, which is indicated by a positive correlation of BHP abundances with Corg and δ15N.

  5. Local level sustainability policies in the Baltic Sea area: Local Agenda 21 within the Union of the Baltic Cities network.

    PubMed

    Joas, M; Grönholm, B

    2001-08-01

    Local Agenda 21 (LA21) processes have 2 central goals. i) On the basis of some of the empirical evidence in this study, the primary goal is to improve democratic (environmental) policy-making processes in such a manner that a larger share of the population will be able to participate in planning and decision making and will also be able to understand the consequences of these decisions. ii) The LA21 processes seek to improve (at least indirectly) the broadly defined environmental situation locally in a manner that takes into account both the local and the global contexts. The first part of this article discusses the concept and methods of LA21 and sheds light on the different action areas that are central to the Baltic LA21 processes. In addition, the study will describe and display the LA21 situation within one network of cities, the Union of the Baltic Cities (UBC). Networking, including transfer of information, models and ideas, has been among the main tools for the diffusion of LA21 ideas especially into newly democratized societies. Finally, the article will conclude with an overall assessment of the LA21 situation on the Baltic rim.

  6. Organohalogen concentrations and feeding status in Atlantic salmon (Salmo salar L.) of the Baltic Sea during the spawning run.

    PubMed

    Vuorinen, Pekka J; Kiviranta, Hannu; Koistinen, Jaana; Pöyhönen, Outi; Ikonen, Erkki; Keinänen, Marja

    2014-01-15

    Changes in the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in Baltic salmon muscle were studied during the spawning migration from the southern Baltic Sea to rivers flowing into the northern Gulf of Bothnia and during the spawning period. The aim was to obtain information to facilitate the arrangement of salmon fisheries such that the human dioxin intake is taken into account. The EC maximum allowable total toxic equivalent concentration (WHO-TEQPCDD/F+PCB) was exceeded in the muscle of the majority of the migrating salmon, except in the Baltic Proper. The fresh-weight-based concentrations of all toxicant groups in salmon tended to be the lowest in the Baltic Proper and the Northern Quark, and all toxicant concentrations, except PCDDs and PCDFs, were significantly higher in the spawning salmon than in the salmon caught during the spawning run. The fat content of the salmon muscle decreased by 60% during the spawning run, and the lipid-based total toxicant concentrations were consequently 4.2-6.2 times higher during the spawning period than during the spawning migration. However, the toxicants were concentrated just before spawning, and thus there is no essential difference related to whether the salmon are caught in the sea or the recreational river fishery.

  7. Classification of Baltic Sea ice types by airborne multifrequency microwave radiometer

    SciTech Connect

    Kurvonen, L.; Hallikainen, M.

    1996-11-01

    An airborne multifrequency radiometer (24, 34, 48, and 94 GHz, vertical polarization) was used to investigate the behavior of the brightness temperature of different sea ice types in the Gulf of Bothnia (Baltic Sea). The measurements and the main results of the analysis are presented. The measurements were made in dry and wet conditions (air temperature above and below 0 C). The angle of incidence was 45{degree} in all measurements. The following topics are evaluated: (a) frequency dependency of the brightness temperature of different ice types, (b) the capability of the multifrequency radiometer to classify ice types for winter navigation purposes, and (c) the optimum measurement frequencies for mapping sea ice. The weather conditions had a significant impact on the radiometric signatures of some ice types (snow-covered compact pack ice and frost-covered new ice); the impact was the highest at 94 GHz. In all cases the overall classification accuracy was around 90% (the kappa coefficient was from 0.86 to 0.96) when the optimum channel combination (24/34 GHz and 94 GHz) was used.

  8. Methane in the Baltic and North Seas and a reassessment of the marine emissions of methane

    SciTech Connect

    Bange, H.W.; Bartell, U.H.; Rapsomanikis, S.

    1994-12-01

    During three measurement campaigns on the Baltic and North Seas, atmospheric and dissolved methane was determined with an automated gas chromatographic system. Area-weighted mean saturation values in the sea surface waters were 113{+-}5% and 395{+-}82% and 126{+-}8%. On the bases of our data and a compilation of literature data the global oceanic emissions of methane were reassessed by introducing a concept of regional gas transfer coefficients. Our estimates computed with two different air-sea exchange models lie in the range of 11-18 Tg CH{sub 4} yr{sup -1}. Despite the fact that shelf areas and estuaries only represent a small part of the world`s ocean they contribute about 75% to the global oceanic emissions. We applied a simple, coupled, three-layer model to evaluate the time dependent variation of the oceanic flux to the atmosphere. The model calculations indicate that even with increasing tropospheric methane concentration, the ocean will remain a source of atmospheric methane. 72 refs., 7 figs., 7 tabs.

  9. Phylogeographical structure, distribution and genetic variation of the green algae Ulva intestinalis and U. compressa (Chlorophyta) in the Baltic Sea area.

    PubMed

    Leskinen, E; Alstrom-Rapaport, C; Pamilo, P

    2004-08-01

    The marine algae Ulva intestinalis and U. compressa are morphologically plastic with many overlapping characters and are therefore difficult to distinguish from each other. The present distribution of U. intestinalis and U. compressa is investigated along the salinity gradient in the Baltic Sea area through analyses of internal transcribed spacer (ITS) sequence data. Also, the amount and distribution of intraspecific genetic polymorphism in the ITS region is studied allowing inferences on the phylogeographical pattern and postglacial recolonization of the Baltic Sea area. The data show that of the two species only U. intestinalis occurs in the Baltic Sea. The distribution of U. compressa is more restricted than previously reported, and it was not found in salinities lower than 15 ppt. All of Scandinavia and the Baltic Sea were covered with ice during the last ice age and the organisms in the Baltic Sea must have colonized the area after the ice had started to melt. The genetic diversity of U. intestinalis and U. compressa in the Baltic Sea and the neighbouring area was found to be reduced compared to that in the British Isles. This reduction may be the result of either a historical reduction of diversity or an adaptation of specific clones to the northern environmental conditions. PMID:15245399

  10. Broad-Scale Climate Influences on Spring-Spawning Herring (Clupea harengus, L.) Recruitment in the Western Baltic Sea

    PubMed Central

    Gröger, Joachim P.; Hinrichsen, Hans-Harald; Polte, Patrick

    2014-01-01

    Climate forcing in complex ecosystems can have profound implications for ecosystem sustainability and may thus challenge a precautionary ecosystem management. Climatic influences documented to affect various ecological functions on a global scale, may themselves be observed on quantitative or qualitative scales including regime shifts in complex marine ecosystems. This study investigates the potential climatic impact on the reproduction success of spring-spawning herring (Clupea harengus) in the Western Baltic Sea (WBSS herring). To test for climate effects on reproduction success, the regionally determined and scientifically well-documented spawning grounds of WBSS herring represent an ideal model system. Climate effects on herring reproduction were investigated using two global indices of atmospheric variability and sea surface temperature, represented by the North Atlantic Oscillation (NAO) and the Atlantic Multi-decadal Oscillation (AMO), respectively, and the Baltic Sea Index (BSI) which is a regional-scale atmospheric index for the Baltic Sea. Moreover, we combined a traditional approach with modern time series analysis based on a recruitment model connecting parental population components with reproduction success. Generalized transfer functions (ARIMAX models) allowed evaluating the dynamic nature of exogenous climate processes interacting with the endogenous recruitment process. Using different model selection criteria our results reveal that in contrast to NAO and AMO, the BSI shows a significant positive but delayed signal on the annual dynamics of herring recruitment. The westward influence of the Siberian high is considered strongly suppressing the influence of the NAO in this area leading to a higher explanatory power of the BSI reflecting the atmospheric pressure regime on a North-South transect between Oslo, Norway and Szczecin, Poland. We suggest incorporating climate-induced effects into stock and risk assessments and management strategies as part

  11. Broad-scale climate influences on spring-spawning herring (Clupea harengus, L.) recruitment in the Western Baltic Sea.

    PubMed

    Gröger, Joachim P; Hinrichsen, Hans-Harald; Polte, Patrick

    2014-01-01

    Climate forcing in complex ecosystems can have profound implications for ecosystem sustainability and may thus challenge a precautionary ecosystem management. Climatic influences documented to affect various ecological functions on a global scale, may themselves be observed on quantitative or qualitative scales including regime shifts in complex marine ecosystems. This study investigates the potential climatic impact on the reproduction success of spring-spawning herring (Clupea harengus) in the Western Baltic Sea (WBSS herring). To test for climate effects on reproduction success, the regionally determined and scientifically well-documented spawning grounds of WBSS herring represent an ideal model system. Climate effects on herring reproduction were investigated using two global indices of atmospheric variability and sea surface temperature, represented by the North Atlantic Oscillation (NAO) and the Atlantic Multi-decadal Oscillation (AMO), respectively, and the Baltic Sea Index (BSI) which is a regional-scale atmospheric index for the Baltic Sea. Moreover, we combined a traditional approach with modern time series analysis based on a recruitment model connecting parental population components with reproduction success. Generalized transfer functions (ARIMAX models) allowed evaluating the dynamic nature of exogenous climate processes interacting with the endogenous recruitment process. Using different model selection criteria our results reveal that in contrast to NAO and AMO, the BSI shows a significant positive but delayed signal on the annual dynamics of herring recruitment. The westward influence of the Siberian high is considered strongly suppressing the influence of the NAO in this area leading to a higher explanatory power of the BSI reflecting the atmospheric pressure regime on a North-South transect between Oslo, Norway and Szczecin, Poland. We suggest incorporating climate-induced effects into stock and risk assessments and management strategies as part

  12. Broad-scale climate influences on spring-spawning herring (Clupea harengus, L.) recruitment in the Western Baltic Sea.

    PubMed

    Gröger, Joachim P; Hinrichsen, Hans-Harald; Polte, Patrick

    2014-01-01

    Climate forcing in complex ecosystems can have profound implications for ecosystem sustainability and may thus challenge a precautionary ecosystem management. Climatic influences documented to affect various ecological functions on a global scale, may themselves be observed on quantitative or qualitative scales including regime shifts in complex marine ecosystems. This study investigates the potential climatic impact on the reproduction success of spring-spawning herring (Clupea harengus) in the Western Baltic Sea (WBSS herring). To test for climate effects on reproduction success, the regionally determined and scientifically well-documented spawning grounds of WBSS herring represent an ideal model system. Climate effects on herring reproduction were investigated using two global indices of atmospheric variability and sea surface temperature, represented by the North Atlantic Oscillation (NAO) and the Atlantic Multi-decadal Oscillation (AMO), respectively, and the Baltic Sea Index (BSI) which is a regional-scale atmospheric index for the Baltic Sea. Moreover, we combined a traditional approach with modern time series analysis based on a recruitment model connecting parental population components with reproduction success. Generalized transfer functions (ARIMAX models) allowed evaluating the dynamic nature of exogenous climate processes interacting with the endogenous recruitment process. Using different model selection criteria our results reveal that in contrast to NAO and AMO, the BSI shows a significant positive but delayed signal on the annual dynamics of herring recruitment. The westward influence of the Siberian high is considered strongly suppressing the influence of the NAO in this area leading to a higher explanatory power of the BSI reflecting the atmospheric pressure regime on a North-South transect between Oslo, Norway and Szczecin, Poland. We suggest incorporating climate-induced effects into stock and risk assessments and management strategies as part

  13. Seasonal development of the properties and composition of landfast sea ice in the Gulf of Finland, the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Granskog, Mats A.; LeppäRanta, Matti; Kawamura, Toshiyuki; Ehn, Jens; Shirasawa, Kunio

    2004-02-01

    The seasonal development of the structure, salinity, and stable oxygen isotopic composition (δ18O) of landfast sea ice was studied during the winter seasons 1999-2001 in the Gulf of Finland in the Baltic Sea. The main focuses were on the seasonal and the interannual variability in ice properties and composition and on the contribution of meteoric ice to sea ice mass balance. Results provide a first statistical description of the seasonal evolution of sea ice in mild ice climate conditions. The ice has a characteristic structure with an upper granular ice layer, composed almost exclusively of superimposed ice and snow-ice, averaging at 20-35% of the total ice thickness. The remaining is composed of columnar or intermediate granular columnar ice, depending on growth conditions. While salinity shows a uniform profile through the ice, δ18O shows lower values in the surface because of meteoric ice formation. The thin ice cover is susceptible to changes in atmospheric conditions, and rapid changes in ice salinity are connected to changes in the ice thermal regime and flooding. The contribution of meteoric ice varied from 0 to 35% (by mass), depending on season and year. Superimposed ice formation is a recurring process and significantly contributed to ice growth (up to 20% by mass), especially late in the season during snowmelt-freeze cycles. Liquid precipitation also cause formation of intermittent superimposed ice layers at these latitudes. The contribution of meteoric ice to sea ice mass balance is largely dependent on the amount and timing of snow accumulation and timing of snowmelt-freeze processes, which all showed large year-to-year variation. The conditions presented here may start to occur at higher latitudes if global warming continues.

  14. Organotins in fish muscle and liver from the Polish coast of the Baltic Sea: Is the total ban successful?

    PubMed

    Filipkowska, Anna; Złoch, Ilona; Wawrzyniak-Wydrowska, Brygida; Kowalewska, Grażyna

    2016-10-15

    Muscle and liver tissues of nine fish species were analyzed to assess butyltin and phenyltin contamination. The samples were collected from three basins located in the Southern Baltic Sea coastal zone that each represent different potential for organotin pollution. Maximum total concentrations of butyltin compounds (BTs) in the fish muscles and livers were 715 and 1132ng Sn g(-1) d.w., respectively, whereas triphenyltin (TPhT) was not detected. In the muscle samples, the predominant compound in the sum of butyltins was tributyltin (TBT), while in the liver samples, tributyltin degradation products were found in the majority. The results demonstrate that 6-7years after the implementation of the total ban on harmful organotin use in antifouling paints, butyltins remain present in fishes from the Polish coast of the Baltic Sea. According to the HELCOM recommendation, eight samples exceeded the good environmental status boundary for tributyltin in seafood. PMID:27345706

  15. Isotopic signatures of eelgrass (Zostera marina L.) as bioindicator of anthropogenic nutrient input in the western Baltic Sea.

    PubMed

    Schubert, Philipp R; Karez, Rolf; Reusch, Thorsten B H; Dierking, Jan

    2013-07-15

    Eutrophication is a global environmental problem. Better management of this threat requires more accurate assessments of anthropogenic nitrogen (N) inputs to coastal systems than can be obtained with traditional measures. Recently, primary producer N isotopic signatures have emerged as useful proxy of such inputs. Here, we demonstrated for the first time the applicability of this method using the widespread eelgrass (Zostera marina) in the highly eutrophic Baltic Sea. Spatial availability of sewage N across a bay with one major sewage outflow predicted by eelgrass δ(15)N was high near and downstream of the outflow compared to upstream, but returned to upstream levels within 4 km downstream from the outfall. General conclusions were corroborated by traditional eutrophication measures, but in contrast to these measures were fully quantitative. Eelgrass N isotope ratios therefore show high potential for coastal screens of eutrophication in the Baltic Sea, and in other areas with eelgrass meadows.

  16. Heavy metal concentrations in sediment cores from the northern Baltic Sea: declines over the last two decades.

    PubMed

    Vallius, Henry

    2014-02-15

    The Baltic Sea has received considerable loads of pollutants due to industrialization in Eastern Europe. Concern for the Baltic's ecological health eventually led to legislation and voluntary measures to limit pollution during the last decades of the 20th century. Heavy metal concentrations in open sea surface sediments reflected these steps to limit contaminant loads almost immediately, suggesting the possibility that the trend would continue in the ensuing years. Recent seafloor samples reveal that the declines have persisted over the past two decades. Currently, almost all heavy metal species have declined in surface sediments to levels approaching the safe limits for humans and the environment. Cadmium and mercury however remain at relatively high concentrations in many areas. Arsenic concentrations, which occur at safe levels within the Gulf of Finland persist at unacceptably high levels in surface sediments of the Bothnian Bay, and thus pose a potential threat to marine life in the area.

  17. Interannual variability of phyto-bacterioplankton biomass and production in coastal and offshore waters of the Baltic Sea.

    PubMed

    Legrand, Catherine; Fridolfsson, Emil; Bertos-Fortis, Mireia; Lindehoff, Elin; Larsson, Per; Pinhassi, Jarone; Andersson, Agneta

    2015-06-01

    The microbial part of the pelagic food web is seldom characterized in models despite its major contribution to biogeochemical cycles. In the Baltic Sea, spatial and temporal high frequency sampling over three years revealed changes in heterotrophic bacteria and phytoplankton coupling (biomass and production) related to hydrographic properties of the ecosystem. Phyto- and bacterioplankton were bottom-up driven in both coastal and offshore areas. Cold winter temperature was essential for phytoplankton to conform to the successional sequence in temperate waters. In terms of annual carbon production, the loss of the spring bloom (diatoms and dinoflagellates) after mild winters tended not to be compensated for by other taxa, not even summer cyanobacteria. These results improve our ability to project Baltic Sea ecosystem response to short- and long-term environmental changes.

  18. Ensemble-based evaluation of extreme water levels for the eastern Baltic Sea

    NASA Astrophysics Data System (ADS)

    Eelsalu, Maris; Soomere, Tarmo

    2016-04-01

    The risks and damages associated with coastal flooding that are naturally associated with an increase in the magnitude of extreme storm surges are one of the largest concerns of countries with extensive low-lying nearshore areas. The relevant risks are even more contrast for semi-enclosed water bodies such as the Baltic Sea where subtidal (weekly-scale) variations in the water volume of the sea substantially contribute to the water level and lead to large spreading of projections of future extreme water levels. We explore the options for using large ensembles of projections to more reliably evaluate return periods of extreme water levels. Single projections of the ensemble are constructed by means of fitting several sets of block maxima with various extreme value distributions. The ensemble is based on two simulated data sets produced in the Swedish Meteorological and Hydrological Institute. A hindcast by the Rossby Centre Ocean model is sampled with a resolution of 6 h and a similar hindcast by the circulation model NEMO with a resolution of 1 h. As the annual maxima of water levels in the Baltic Sea are not always uncorrelated, we employ maxima for calendar years and for stormy seasons. As the shape parameter of the Generalised Extreme Value distribution changes its sign and substantially varies in magnitude along the eastern coast of the Baltic Sea, the use of a single distribution for the entire coast is inappropriate. The ensemble involves projections based on the Generalised Extreme Value, Gumbel and Weibull distributions. The parameters of these distributions are evaluated using three different ways: maximum likelihood method and method of moments based on both biased and unbiased estimates. The total number of projections in the ensemble is 40. As some of the resulting estimates contain limited additional information, the members of pairs of projections that are highly correlated are assigned weights 0.6. A comparison of the ensemble-based projection of

  19. Environmental Gradients Explain Species Richness and Community Composition of Coastal Breeding Birds in the Baltic Sea

    PubMed Central

    Nord, Maria; Forslund, Pär

    2015-01-01

    Scientifically-based systematic conservation planning for reserve design requires knowledge of species richness patterns and how these are related to environmental gradients. In this study, we explore a large inventory of coastal breeding birds, in total 48 species, sampled in 4646 1 km2 squares which covered a large archipelago in the Baltic Sea on the east coast of Sweden. We analysed how species richness (α diversity) and community composition (β diversity) of two groups of coastal breeding birds (specialists, i.e. obligate coastal breeders; generalists, i.e. facultative coastal breeders) were affected by distance to open sea, land area, shoreline length and archipelago width. The total number of species per square increased with increasing shoreline length, but increasing land area counteracted this effect in specialists. The number of specialist bird species per square increased with decreasing distance to open sea, while the opposite was true for the generalists. Differences in community composition between squares were associated with differences in land area and distance to open sea, both when considering all species pooled and each group separately. Fourteen species were nationally red-listed, and showed similar relationships to the environmental gradients as did all species, specialists and generalists. We suggest that availability of suitable breeding habitats, and probably also proximity to feeding areas, explain much of the observed spatial distributions of coastal birds in this study. Our findings have important implications for systematic conservation planning of coastal breeding birds. In particular, we provide information on where coastal breeding birds occur and which environments they seem to prefer. Small land areas with long shorelines are highly valuable both in general and for red-listed species. Thus, such areas should be prioritized for protection against human disturbance and used by management in reserve selection. PMID:25714432

  20. Environmental gradients explain species richness and community composition of coastal breeding birds in the Baltic Sea.

    PubMed

    Nord, Maria; Forslund, Pär

    2015-01-01

    Scientifically-based systematic conservation planning for reserve design requires knowledge of species richness patterns and how these are related to environmental gradients. In this study, we explore a large inventory of coastal breeding birds, in total 48 species, sampled in 4646 1 km2 squares which covered a large archipelago in the Baltic Sea on the east coast of Sweden. We analysed how species richness (α diversity) and community composition (β diversity) of two groups of coastal breeding birds (specialists, i.e. obligate coastal breeders; generalists, i.e. facultative coastal breeders) were affected by distance to open sea, land area, shoreline length and archipelago width. The total number of species per square increased with increasing shoreline length, but increasing land area counteracted this effect in specialists. The number of specialist bird species per square increased with decreasing distance to open sea, while the opposite was true for the generalists. Differences in community composition between squares were associated with differences in land area and distance to open sea, both when considering all species pooled and each group separately. Fourteen species were nationally red-listed, and showed similar relationships to the environmental gradients as did all species, specialists and generalists. We suggest that availability of suitable breeding habitats, and probably also proximity to feeding areas, explain much of the observed spatial distributions of coastal birds in this study. Our findings have important implications for systematic conservation planning of coastal breeding birds. In particular, we provide information on where coastal breeding birds occur and which environments they seem to prefer. Small land areas with long shorelines are highly valuable both in general and for red-listed species. Thus, such areas should be prioritized for protection against human disturbance and used by management in reserve selection.

  1. Evaluation of the operational SAR based Baltic Sea ice concentration products

    NASA Astrophysics Data System (ADS)

    Karvonen, Juha

    2015-07-01

    Sea ice concentration is an important ice parameter both for weather and climate modeling and sea ice navigation. We have developed an fully automated algorithm for sea ice concentration retrieval using dual-polarized ScanSAR wide mode RADARSAT-2 data. RADARSAT-2 is a C-band SAR (Synthetic Aperture Radar) instrument enabling dual-polarized acquisition in ScanSAR mode. The swath width for the RADARSAT-2 ScanSAR mode is about 500 km, making it very suitable for operational sea ice monitoring. The polarization combination used in our concentration estimation is HH/HV. The SAR data is first preprocessed; the preprocessing consists of geo-rectification to Mercator projection, incidence angle correction for both the polarization channels, and SAR mosaicking. After preprocessing a segmentation is performed for the SAR mosaics, and some features are computed for each SAR segment. Finally the SAR concentration is estimated based on these segment-wise features. The algorithm is basically similar as introduced in Karvonen 2014. The ice concentration is computed daily using a daily RADARSAT-2 SAR mosaic as its input, and it thus gives the concentration estimated at each grid cell (pixel) based on the most recent SAR data at the location. The algorithm has been run in an operational test mode since January 2014. We present evaluation of the SAR-based concentration estimates for the Baltic ice season 2014 by comparing the SAR results with gridded Finnish Meteorological Institute (FMI) ice charts and ice concentration estimates from a radiometer algorithm.

  2. Environmental gradients explain species richness and community composition of coastal breeding birds in the Baltic Sea.

    PubMed

    Nord, Maria; Forslund, Pär

    2015-01-01

    Scientifically-based systematic conservation planning for reserve design requires knowledge of species richness patterns and how these are related to environmental gradients. In this study, we explore a large inventory of coastal breeding birds, in total 48 species, sampled in 4646 1 km2 squares which covered a large archipelago in the Baltic Sea on the east coast of Sweden. We analysed how species richness (α diversity) and community composition (β diversity) of two groups of coastal breeding birds (specialists, i.e. obligate coastal breeders; generalists, i.e. facultative coastal breeders) were affected by distance to open sea, land area, shoreline length and archipelago width. The total number of species per square increased with increasing shoreline length, but increasing land area counteracted this effect in specialists. The number of specialist bird species per square increased with decreasing distance to open sea, while the opposite was true for the generalists. Differences in community composition between squares were associated with differences in land area and distance to open sea, both when considering all species pooled and each group separately. Fourteen species were nationally red-listed, and showed similar relationships to the environmental gradients as did all species, specialists and generalists. We suggest that availability of suitable breeding habitats, and probably also proximity to feeding areas, explain much of the observed spatial distributions of coastal birds in this study. Our findings have important implications for systematic conservation planning of coastal breeding birds. In particular, we provide information on where coastal breeding birds occur and which environments they seem to prefer. Small land areas with long shorelines are highly valuable both in general and for red-listed species. Thus, such areas should be prioritized for protection against human disturbance and used by management in reserve selection. PMID:25714432

  3. A statistical approach on upwelling in the Baltic Sea based on the analysis of satellite data for 1990-

    NASA Astrophysics Data System (ADS)

    Myrberg, K.; Lehmann, A.; Höflich, K.

    2012-04-01

    A statistical analysis of Baltic Sea upwelling has been carried out to cover, for the first time, the entire sea area for the period 1990-2009. Weekly composite SST maps based on NOAA/ AVHRR satellite data were used to evaluate the location and frequency of upwelling. The results btained were analyzed and compared with earlier studies, including both measurements and modeling with an excellent agreement. Our study enables to evaluate the most intense upwelling areas in the entire Baltic Sea. According to the analysis of 443 SST maps, among the most common upwelling regions are found at the Swedish south and east coast (frequency 10-25%), the Swedish coast of the Bothnian Bay (16%), the southern tip of Gotland island (up to 15%), and the Finnish coast of the Gulf of Finland (up to 15%). Pronounced upwelling occurs also at the Estonian coast and Baltic east coast (up to 15%), the Polish coast and west coast of Rügen island (10-15%), otherwise upwelling frequency was between 5 to 10 %. Additionally, simulated SST distributions derived from a Baltic Sea numerical model have been analyzed for the same period. Furthermore, at specific positions close to the coastline, surface winds based on the SMHI meteorological data base have been analyzed for the same 20-year period. Wind components parallel to the coast have been discriminated into favorable and unfavorable winds forcing upwelling. The obtained frequencies of upwelling favorable winds fit very well with observed upwelling frequencies derived from satellite SST maps. For the period 1990-2009 a positive trend of upwelling frequencies along the Swedish east coast and the Finnish coast of the Gulf of Finland was calculated.

  4. Evaluation of biogeochemical cycles in an ensemble of three state-of-the-art numerical models of the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Eilola, K.; Gustafsson, B. G.; Kuznetsov, I.; Meier, H. E. M.; Neumann, T.; Savchuk, O. P.

    2011-11-01

    Three state-of-the-art coupled physical-biogeochemical models, the BAltic sea Long-Term large-Scale Eutrophication Model (BALTSEM), the Ecological Regional Ocean Model (ERGOM), and the Swedish Coastal and Ocean Biogeochemical model coupled to the Rossby Centre Ocean circulation model (RCO-SCOBI), are used to calculate changing nutrient and oxygen dynamics in the Baltic Sea. The models are different in that ERGOM and RCO-SCOBI are three-dimensional (3D) circulation models while BALTSEM resolves the Baltic Sea into 13 dynamically interconnected and horizontally integrated sub-basins. The aim is to assess the simulated long-term dynamics and to discuss the response of the coupled physical-biogeochemical models to changing physical conditions and nutrient loadings during the period 1970-2005. We compared the long-term seasonal and annual statistics of inorganic nitrogen, phosphorus, and oxygen from hindcast simulations with those estimated from observations. We also studied the extension of hypoxic bottom areas covered by waters with O 2 < 2 ml O 2 l - 1 and cod reproductive volumes comprising waters with salinity > 11 and O 2 > 2 ml O 2 l - 1 . The models reproduce much of the nutrient biogeochemical cycling in the Baltic proper. However, biases are larger in the Bothnian Sea and Bothnian Bay. No model shows outstanding performance in all aspects but instead the ensemble mean results are better than or as good as the results of any of the individual models. Uncertainties are primarily related to differences in the bioavailable fractions of nutrient loadings from land and parameterizations of key processes like sediment fluxes that are presently not well known. Also the uncertainty related to the initialization of the models in the early 1960s influence the modeled biogeochemical cycles during the investigated period.

  5. The relative importance of selected factors controlling the oxygen dynamics in the water column of the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Miladinova, S.; Stips, A.

    2009-09-01

    A 1-D biogeochemical/physical model of marine systems has been applied to study the oxygen cycle in four stations of the different sub-basins of the Baltic Sea, namely, in Gotland Deep, Bornholm, Arkona and Fladen. The model consists of biogeochemical model of Neumann et al. (2002) coupled with the 1-D General Ocean Turbulence Model (GOTM). The model has been forced with meteorological data from the ECMWF reanalysis project for the period 1998-2003, producing a 6-year hindcast validated with datasets from the Baltic Environmental Database (BED) for the same period. The vertical profiles of temperature and salinity are relaxed towards both profiles provided by 3-D simulations of General Estuarine Turbulent Model (GETM) and observed profiles from BED. Modifications in the parameterisation of the air/sea oxygen fluxes have led to significant improvement of the model results in the surface and intermediate water levels. The largest mismatch with observation is found in simulating the oxygen dynamics in the Baltic Sea bottom waters. The model results demonstrate the good capability of the model to predict the time-evolution of the physical and biogeochemical variables at all different stations. Comparative analysis of the modelled oxygen concentrations with respect to the observation data is performed to distinguish the relative importance of several factors on the seasonal, interannual and long-term variations of oxygen. It is found that the natural physical factors, like the magnitude of the vertical turbulent mixing, wind speed, the variation in temperature and salinity field are the major factors controlling the oxygen dynamics in the Baltic Sea. The influence of limiting nutrients is less pronounced, at least under the nutrient flux parameterisation assumed in the model.

  6. Seasonal contribution of terrestrial organic matter and biological oxygen demand to the Baltic Sea from three contrasting river catchments

    NASA Astrophysics Data System (ADS)

    Reader, H. E.; Stedmon, C. A.; Kritzberg, E. S.

    2014-01-01

    To examine the potential influence of terrestrially derived DOM on the Baltic Sea, a year-long study of dissolved organic matter (DOM) was performed in three river catchments in Sweden. One catchment drains into the Bothnian Sea, while two southern catchments drain into the Baltic Proper. Dissolved organic carbon (DOC) concentrations were positively correlated with discharge from forested catchments over the year and while the overall concentrations of DOC were several times higher in the southern two catchments, annual loading of DOC was on the same order for all three catchments, due to differences in discharge. Biological oxygen demand (BOD) was used as a proxy for the lability of carbon in the system. The range of BOD values was similar for all three catchments, however, the ratio of BOD to DOC (an indication of the labile fraction) in Ume älv was four times higher than in the southern two catchments. Total annual BOD loading to the Baltic Sea was twice as high in the northern catchment. Lower winter temperatures and preservation of organic matter in the northern catchment combined with an intense spring flood help to explain the higher concentrations of labile carbon in the northern catchment. Lower lability of DOM as well as higher colour in the southern catchments suggest that wetlands (i.e. peat bogs) may be the dominant source of DOM in these catchments, particularly in periods of low flow. With climate change expected to increase precipitation events and temperatures across the region, the supply and quality of DOM delivered to the Baltic Sea can also be expected to change. Our results indicate that DOM supply will be more stable throughout the year, and potentially have a lower bioavailability.

  7. Seasonal and diel variability of the underwater noise in the Baltic Sea.

    PubMed

    Klusek, Zygmunt; Lisimenka, Aliaksandr

    2016-04-01

    The results of ambient sea noise measurements performed in strongly stratified shallow basins in the southern Baltic Sea are presented. The experiments were conducted with an autonomous hydroacoustic buoy that was equipped with two omnidirectional hydrophones located inside and outside the seasonal waveguide. Data were collected in two areas with contrastingly diverse sound propagation conditions-at the Bornholm Deep in winter and at the Gdansk Deep in summer. The noise spectrum levels indicate a strong dependence on the sound propagation conditions (season, location) and show significant differences with the observation depth. At frequencies f < 1 kHz, the noise at the same wind speeds is approximately 10-15 dB higher in winter than in summer. The wind-driven component of the noise frequently does not match the patterns of the Knudsen curves. Furthermore, the noise demonstrates the diel variability. The relative differences of the noise spectrum levels inside and outside of the subsurface winter waveguide reveal regular changes by as much as 15 dB, and are the most visible in the frequency range of 1-2 kHz after sunset. The changes are synchronized with the vertical migration of marine organisms and correspond to the resonant frequencies of the fishes' swim bladders. PMID:27106302

  8. Brackish-water submergence of the common periwinkle, Littorina littorea, and its digenean parasites in the Baltic Sea and in the Kattegat

    NASA Astrophysics Data System (ADS)

    Lauckner, G.

    1984-03-01

    North Sea and Baltic Sea populations of Littorina littorea differ with respect to their vertical distribution. In the North Sea L. littorea is strictly intertidal while in the Baltic Sea maximum population densities occur in the sublittoral. Levels of infestation with larval digenetic trematodes diminish qualitatively (number of species recorded) and quantitatively (number of hosts infested) with decreasing salinity. Both the host and two parasite species — Cryptocotyle lingua and Microphallus pygmaeus — display ‘brackish-water submergence’ under conditions of reduced surface salinity.

  9. Distribution of /sup 137/Cs in samples of ocean bottom sediments of the baltic sea in 1982-1983

    SciTech Connect

    Gedenov, L.I.; Flegontov, V.M.; Ivanova, L.M.; Kostandov, K.A.

    1986-03-01

    The concentration of Cs-137 in samples of ocean bottom sediments picked up in 1979 in the Gulf of Finland with a geological nozzle pipe varied within a wide interval of values. The results could indicate nonuniformity of the Cs-137 distribution in ocean bottom sediments as well as the penetration of significant amounts of Cs-137 to large depths. The main error resulted from the sampling technique employed because the upper part of the sediment could be lost. In 1982, a special ground-sampling device, with which the upper layer of sediments in the water layer close to the ocean bottom could be sampled, was tested in the Gulf of Finland and the Northeastern part of the Baltic Sea. The results of a layerwise determination of the Cs-137 concentration in samples of ocean bottom sediments of the Gulf of Finland and of the Baltic Sea are listed. The new soil-sampling device for picking samples of ocean sediments of undisturbed stratification will allow a correct determination of the radionuclide accumulation in the upper layers of ocean bottom sediments in the Baltic Sea.

  10. Hierarchy of factors exerting an impact on nutrient load of the Baltic Sea and sustainable management of its drainage basin.

    PubMed

    Kiedrzyńska, Edyta; Jóźwik, Adam; Kiedrzyński, Marcin; Zalewski, Maciej

    2014-11-15

    The aim of the paper was to evaluate 23 catchment factors that determine total phosphorus and total nitrogen load to the Baltic Sea. Standard correlation analysis and clustering were used. Both phosphorus and nitrogen loads were found to be positively related to the number of pigs and the human population associated with wastewater treatment plants (WWTPs) per km(2), while the number of cattle and agricultural area were found to influence nitrogen rather than phosphorus load, and the area of forests is negatively related to loads of both nutrients. Clustering indicates an overall north-south pattern in the spatial co-occurrence of socio-ecological factors, with some exceptions discussed in the paper. Positive steps in the Baltic Sea region have already been taken, but much remains to be done. The development of coherent response policies to reduce eutrophication in the Baltic Sea should be based on a comprehensive knowledge base, an appropriate information strategy and learning alliance platform in each drainage river catchments.

  11. Methodological Challenges in Assessing the Environmental Status of a Marine Ecosystem: Case Study of the Baltic Sea

    PubMed Central

    2011-01-01

    Assessments of the environmental status of marine ecosystems are increasingly needed to inform management decisions and regulate human pressures to meet the objectives of environmental policies. This paper addresses some generic methodological challenges and related uncertainties involved in marine ecosystem assessment, using the central Baltic Sea as a case study. The objectives of good environmental status of the Baltic Sea are largely focusing on biodiversity, eutrophication and hazardous substances. In this paper, we conduct comparative evaluations of the status of these three segments, by applying different methodological approaches. Our analyses indicate that the assessment results are sensitive to a selection of indicators for ecological quality objectives that are affected by a broad spectrum of human activities and natural processes (biodiversity), less so for objectives that are influenced by a relatively narrow array of drivers (eutrophications, hazardous substances). The choice of indicator aggregation rule appeared to be of essential importance for assessment results for all three segments, whereas the hierarchical structure of indicators had only a minor influence. Trend-based assessment was shown to be a useful supplement to reference-based evaluation, being independent of the problems related to defining reference values and indicator aggregation methodologies. Results of this study will help in setting priorities for future efforts to improve environmental assessments in the Baltic Sea and elsewhere, and to ensure the transparency of the assessment procedure. PMID:21559423

  12. Effects of climate change and agricultural adaptation on nutrient loading from Finnish catchments to the Baltic Sea.

    PubMed

    Huttunen, Inese; Lehtonen, Heikki; Huttunen, Markus; Piirainen, Vanamo; Korppoo, Marie; Veijalainen, Noora; Viitasalo, Markku; Vehviläinen, Bertel

    2015-10-01

    Climate change is expected to increase annual and especially winter runoff, shorten the snow cover period and therefore increase both nutrient leaching from agricultural areas and natural background leaching in the Baltic Sea catchment. We estimated the effects of climate change and possible future scenarios of agricultural changes on the phosphorus and nitrogen loading to the Baltic Sea from Finnish catchments. In the agricultural scenarios we assumed that the prices of agricultural products are among the primary drivers in the adaptation to climate change, as they affect the level of fertilization and the production intensity and volume and, hence, the modeled changes in gross nutrient loading from agricultural land. Optimal adaptation may increase production while supporting appropriate use of fertilization, resulting in low nutrient balance in the fields. However, a less optimal adaptation may result in higher nutrient balance and increased leaching. The changes in nutrient loading to the Baltic Sea were predicted by taking into account the agricultural scenarios in a nutrient loading model for Finnish catchments (VEMALA), which simulates runoff, nutrient processes, leaching and transport on land, in rivers and in lakes. We thus integrated the effects of climate change in the agricultural sector, nutrient loading in fields, natural background loading, hydrology and nutrient transport and retention processes.

  13. Transport of (137)Cs, (241)Am and Pu isotopes in the Curonian Lagoon and the Baltic Sea.

    PubMed

    Lujanienė, G; Remeikaitė-Nikienė, N; Garnaga, G; Jokšas, K; Šilobritienė, B; Stankevičius, A; Šemčuk, S; Kulakauskaitė, I

    2014-01-01

    Activities of (137)Cs, (241)Am and (239,240)Pu were analyzed with special emphasis on better understanding of radionuclide transport from land via the Neman River estuaries to the Baltic Sea and behavior in the marine environment. Although activity concentrations of (137)Cs in water samples collected the Baltic Sea were almost 100 times higher as compared to the Curonian Lagoon, its activities in the bottom sediments were found to be comparable. Activity (238)Pu/(239,240)Pu and atom (240)Pu/(239)Pu ratios indicated a different contribution of the Chernobyl-originated Pu to the suspended particulate matter (SPM) and bottom sediments. The largest amount of the Chernobyl-derived Pu was found in the smallest suspended matter particles of 0.2-1 μm in size collected in the Klaipeda Strait in 2011-2012. The decrease of characteristic activity (238)Pu/(239,240)Pu and atom (240)Pu/(239)Pu ratios towards the global fallout ones in surface soil and the corresponding increase of plutonium (Pu) ratios in the suspended particulate matter and bottom sediments have indicated that the Chernobyl-derived Pu, primarily deposited on the soil surface, was washed out and transported to the Baltic Sea. Behavior of (241)Am was found to be similar to that of Pu isotopes.

  14. Integrated modelling and management of nutrients and eutrophication in river basin - coast - sea systems: A southern Baltic Sea perspective

    NASA Astrophysics Data System (ADS)

    Schernewski, Gerald

    2014-05-01

    The Odra river basin (area: 120,000 km2, average discharge: 550 m³/s, annual N-load 60,000 t) and the Oder (Szczecin) Lagoon (687 km²) are the eutrophication hot-spot in the south-western Baltic region. To be able to carry out large scale, spatially integrative analyses, we linked the river basin nutrient flux model MONERIS to the coastal 3D-hydrodynamic and ecosystem model ERGOM. Objectives were a) to analyse the eutrophication history in the river basin and the resulting functional changes in the coastal waters between early 1960's and today and b) to analyse the effects of nitrogen and phosphorus management scenarios in the Oder/Odra river basin on coastal and Baltic Sea water quality. The models show that an optimal river basin management with reduced nutrient loads (e.g. N-load reduction of 35%) would have positive effects on lagoon water quality and algae biomass. The availability of nutrients, N/P ratios and processes like denitrification and nitrogen-fixation would show spatial and temporal changes. It would have positive consequences for ecosystems functions, like the nutrient retention capacity, as well. However, this optimal scenario is by far not sufficient to ensure a good coastal water quality according to the European Water Framework Directive. A "good" water quality in the river will not be sufficient to ensure a "good" water quality in the coastal waters. Further, nitrogen load reductions bear the risk of increased potentially toxic, blue-green algae blooms. The presentation will a) summarize recent results (Schernewski et al. 2009, Schernewski et al. 2011, 2012), b) give an overview how the models were used to provide a comprehensive and consistent set of water quality thresholds and maximum allowable riverine loads for the Water Framework Directive and c) will show the implications for an optimised river basin - lagoon quality management.

  15. Comparison of Chlorophyll-A Algorithms for the Transition Zone Between the North Sea and Baltic Sea

    NASA Astrophysics Data System (ADS)

    Huber, Silvia; Hansen, Lars B.; Rasmussen, Mads O.; Kaas, Hanne

    2015-12-01

    Monitoring water quality of the transition zone between the North Sea and Baltic Sea from space is still a challenge because of the optically complex waters. The presence of suspended sediments and dissolved substances often interfere with the phytoplankton signal and thus confound conventional case-1 algorithms developed for the open ocean. Specific calibration to case-2 waters may compensate for this. In this study we compared chlorophyll-a (chl-a) concentrations derived with three different case-2 algorithms: C2R, FUB/WeW and CoastColour using MERIS data as basis. Default C2R and FUB clearly underestimate higher chl-a concentrations. However, with local tuning we could significantly improve the fit with in-situ data. For instance, the root mean square error is reduced by roughly 50% from 3.06 to 1.6 μ g/L for the calibrated C2R processor as compared to the default C2R. This study is part of the FP7 project AQUA-USERS which has the overall goal to provide the aquaculture industry with timely information based on satellite data and optical in-situ measurements. One of the products is chlorophyll-a concentration.

  16. PBB levels in fish from the Baltic and North seas and in selected food products from Poland.

    PubMed

    Gieroń, Joanna; Grochowalski, Adam; Chrzaszcz, Ryszard

    2010-03-01

    Recently, a significant amount of attention has been devoted to the determination of polybrominated biphenyls in food and the environment. In this study, PBB contamination of fish from the North and Baltic Seas, with a special focus on samples from Poland and France, was investigated. North Sea fish like salmon, herring, scarp, gilthead seabream and grey gurnard were collected from a French fish market. Baltic Sea fish like salmon, tunny, trout, herring, and freshwater fish such as carp were purchased from a Polish fish market. Cod livers in oil were also analyzed in this study. As additional food samples, butter, pork fat and beef fat were tested. Concentrations of PBBs in North Sea fish (except herring) were higher than in fish from the Baltic Sea. The highest total PBB concentration was measured in scarp muscle tissue (635+/-107 pg g(-1) wet weight), and the lowest was in carp samples (0.567+/-0.245 pg g(-1) wet weight). The PBB content in tunny oil samples was below the detection limits (0.45-1.05 pg g(-1)fat). Our study also demonstrated that PBBs may bioaccumulate in the liver, where PBB concentrations were 2116+/-351 pg g(-1) wet weight and 841+/-147 pg g(-1) wet weight. In fish species from Poland, the most dominant congeners were tetrabromobiphenyls, followed by pentabromobiphenyls and hexabromobiphenyls. In some species of fish from the North Sea, the most dominant groups were hexabromobiphenyls and tetrabromobiphenyls. Although the relative abundances of structurally known and unknown isomers varied from species to species, all fish (except tunny) were contaminated with PBBs. PMID:20060998

  17. Ecologically relevant choanoflagellates collected from hypoxic water masses of the Baltic Sea have untypical mitochondrial cristae

    PubMed Central

    2012-01-01

    Background Protist communities inhabiting oxygen depleted waters have so far been characterized through both microscopical observations and sequence based techniques. However, the lack of cultures for abundant taxa severely hampers our knowledge on the morphology, ecology and energy metabolism of hypoxic protists. Cultivation of such protists has been unsuccessful in most cases, and has never yet succeeded for choanoflagellates, even though these small bacterivorous flagellates are known to be ecologically relevant components of aquatic protist communities. Results Quantitative data for choanoflagellates and the vertical distribution of Codosiga spp. at Gotland and Landsort Deep (Baltic Sea) indicate its preference for oxygen-depleted zones. Strains isolated and cultivated from these habitats revealed ultrastructural peculiarities such as mitochondria showing tubular cristae never seen before for choanoflagellates, and the first observation of intracellular prokaryotes in choanoflagellates. Analysis of their partial 28S rRNA gene sequence complements the description of two new species, Codosiga minima n. sp. and C. balthica n. sp. These are closely related with but well separated from C. gracilis (C. balthica and C. minima p-distance to C. gracilis 4.8% and 11.6%, respectively). In phylogenetic analyses the 18S rRNA gene sequences branch off together with environmental sequences from hypoxic habitats resulting in a wide cluster of hypoxic Codosiga relatives so far only known from environmental sequencing approaches. Conclusions Here, we establish the morphological and ultrastructural identity of an environmental choanoflagellate lineage. Data from microscopical observations, supplemented by findings from previous culture-independent methods, indicate that C. balthica is likely an ecologically relevant player of Baltic Sea hypoxic waters. The possession of derived mitochondria could be an adaptation to life in hypoxic environments periodically influenced by small

  18. Molecular identification key based on PCR/RFLP for three polychaete sibling species of the genus Marenzelleria, and the species' current distribution in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Blank, M.; Laine, A. O.; Jürss, K.; Bastrop, R.

    2008-06-01

    Studies of Marenzelleria species were often hampered by identification uncertainties when using morphological characters only. A newly developed PCR/RFLP protocol allows a more efficient discrimination of the three species Marenzelleria viridis, Marenzelleria neglecta and Marenzelleria arctia currently known for the Baltic Sea. The protocol is based on PCR amplification of two mitochondrial DNA gene segments (16S, COI) followed by digestion with restriction enzymes. As it is faster and cheaper than PCR/sequencing protocols used so far, the protocol is recommended for large-scale analyses. The markers allow an undoubted determination of species irrespective of life stage or condition of the worms in the samples. The protocol was validated on about 950 specimens sampled at more than 30 sites of the Baltic and the North Sea, and on specimens from populations of the North American east coast. Besides this test we used mitochondrial DNA sequences (16S, COI, Cytb) and starch gel electrophoresis to further investigate the distribution of the three Marenzelleria species in the Baltic Sea. The results show that M. viridis (formerly genetic type I or M. cf. wireni) occurred in the Öresund area, in the south western as well as in the eastern Baltic Sea, where it is found sympatric with M. neglecta. Allozyme electrophoresis indicated an introduction by range expansion from the North Sea. The second species, M. arctia, was only found in the northern Baltic Sea, where it sometimes occurred sympatric with M. neglecta or M. viridis. For Baltic M. arctia, the most probable way of introduction is by ship ballast water from the European Arctic. There is an urgent need for a new genetic analysis of all Marenzelleria populations of the Baltic Sea to unravel the current distribution of the three species.

  19. Emergence of the Zoonotic Biliary Trematode Pseudamphistomum truncatum in Grey Seals (Halichoerus grypus) in the Baltic Sea

    PubMed Central

    Bergman, Anders; Bignert, Anders; Höglund, Johan; Lundström, Karl; Strömberg, Annika; Bäcklin, Britt-Marie

    2016-01-01

    The biliary trematode Pseudamphistomum truncatum parasitizes a wide range of fish-eating mammals, including humans. Here we report the emergence of this parasite in grey seals (Halichoerus grypus) in the Baltic Sea. One hundred eighty-three of 1 554 grey seals (11.9%) examined from 2002–2013 had detectable hepatobiliary trematode infection. Parasite identification was confirmed as P. truncatum by sequencing the ITS2 region of a pool of five to 10 trematodes from each of ten seals collected off the coast of seven different Swedish counties. The proportion of seals parasitized by P. truncatum increased significantly over time and with increasing age of seals. Males were 3.1 times more likely to be parasitized than females and animals killed in fishery interactions were less likely to be parasitized than animals found dead or hunted. There was no significant difference in parasitism of seals examined from the Gulf of Bothnia versus those examined from the Baltic Proper. Although the majority of infections were mild, P. truncatum can cause severe hepatobiliary disease and resulted in liver failure in at least one seal. Because cyprinid fish are the second intermediate host for opisthorchiid trematodes, diets of grey seals from the Baltic Sea were analysed regarding presence of cyprinids. The proportion of gastrointestinal tracts containing cyprinid remains was ten times higher in seals examined from 2008 to 2013 (12.2%) than those examined from 2002 to 2007 (1.2%) and coincided with a general increase of trematode parasitism in the host population. The emergence and relatively common occurrence of P. truncatum in grey seals signals the presence of this parasite in the Baltic Sea ecosystem and demonstrates how aquatic mammals can serve as excellent sentinels of marine ecosystem change. Investigation of drivers behind P. truncatum emergence and infection risk for other mammals, including humans, is highly warranted. PMID:27755567

  20. Artificial radionuclides ⁹⁰Sr and ²⁴¹Am in the sediments of the Baltic Sea: total and spatial inventories and some temporal trends.

    PubMed

    Hutri, Kaisa-Leena; Mattila, Jukka; Ikäheimonen, Tarja Tuulikki; Vartti, Vesa-Pekka

    2013-05-15

    The Baltic Sea was contaminated by radioactivity following global nuclear fallout and later by the Chernobyl accident. Despite the decrease of radioactivity caused by radioactive decay, radionuclides have a prolonged residence time in the water of the Baltic Sea due to slow water exchange and relatively rapid sedimentation. Very little is known about the amounts or spatial differences of ⁹⁰Sr and ²⁴¹Am in the Baltic Sea sediments. In this study, 20 sediment cores taken around the Baltic Sea were investigated to estimate inventories of these radionuclides. The rough results show that the Chernobyl fallout added the amount of ⁹⁰Sr in the same areas where the increase of ¹³⁷Cs can be detected, whereas this is not the case for ²⁴¹Am which is more evenly distributed in the sea bottom. In addition, local differences occur in the concentrations. These results are an important amendment to the radioactivity baseline of the Baltic Sea.

  1. CLIMLINK: Climate forcing factors for marine environmental change during the mid- and late Holocene - a link between the NE Atlantic and the Baltic Sea.

    NASA Astrophysics Data System (ADS)

    Polovodova Asteman, Irina; Risebrobakken, Bjørg; Bąk, Małgorzata; Binczewska, Anna; Borówka, Ryszard; Dobosz, Sławomir; Jansen, Eystein; Kaniak, Aleksandra; Moros, Matthias; Perner, Kerstin; Sławinska, Joanna

    2015-04-01

    Climate change has a strong amplifying effect on the environment of marginal seas such as the Baltic Sea. Owing to the connection of the Baltic Sea with the Atlantic (and the resultant pathway of water exchange via the narrow Danish Straits), changes in the Baltic region are suggested to be driven by external oceanic and atmospheric forcing originating in the Atlantic, particularly in the eastern Nordic seas, the Skagerrak, and the Kattegat. CLIMLINK aims to reconstruct mid- to late Holocene ecosystem changes in these regions and identify linkages, common forcing factors and effects for the Baltic Sea on a millennial to decadal time scale. High-resolution sediment records from selected key sites in the Norwegian Trench, and central Baltic Sea are studied by using a multi-proxy approach. Micropalaeontological studies of diatoms and foraminifera are combined with geochemical proxies, such as stable isotopes, Mg/Ca, TOC, TIC, C/N, XRF and magnetic susceptibility in order to achieve a more comprehensive view on environmental changes during the last 6000 to 8000 years. The chronology of the sediment cores is secured by using multiple dating tools: Hg-pollution records, 137Cs, 210Pb, 14C and tephra layers. Herein we present the initial results of the project.

  2. Evidence of latitudinal fractionation of polychlorinated biphenyl congeners along the Baltic Sea region

    SciTech Connect

    Agrell, C.; Okla, L.; Larsson, P.; Backe, C.; Wania, F.

    1999-04-15

    Annual cycles of the atmospheric concentrations of PCBs were determined at 16 (mostly rural) stations around the Baltic Sea between 1990 and 1993. The concentration levels of individual congeners were found to be influenced by their physical-chemical properties, ambient temperature, and geographical location. Median levels of PCBs were similar at all stations except at one urban site near Riga. A latitudinal gradient with higher levels in the south was found for the sum of PCB as well as for individual congeners, and the gradient was more pronounced for the low volatility congeners. As a result, the high volatility congeners increased in relative importance with latitude. Generally, PCB concentrations increased with temperature, but slopes of the partial pressure in air versus reciprocal temperature were different between congeners and between stations. In general, the low volatility congeners were more temperature dependent than the high volatility PCB congeners. Steep slopes at a sampling location indicate that the concentration in air is largely determined by diffusive exchange with soils. Lack of a temperature dependence may be due to the influence of long-range transported air masses at remote sites and due to the episodic or random nature of PCB sources at urban sites.

  3. Nitrification rates in the Baltic Sea: comparison of three isotope techniques

    SciTech Connect

    Enoksson, V.

    1986-02-01

    Simultaneous measurements of nitrification in the Baltic Sea were made at 10- to 30-m intervals in the months of June and November by three isotope techniques: (/sup 15/N)nitrate dilution, N-serve sensitive (/sup 14/C)bicarbonate incorporation, and (/sup 15/N)ammonium oxidation to nitrite and nitrate. Nitrification rates of 1 to 280 nmol liter/sup -1/ day/sup -1/ were recorded, and each method showed that the highest rates of nitrification occurred below the halocline. Even in the presence of ammonium, dark incubations of mixed layer (above ca. 50 m) waters never yielded nitrification rates exceeding 45 nmol liter/sup -1/ day/sup -1/. The rates measured by the ammonium oxidation method were two- to sevenfold greater than those obtained by /sup 14/C incorporation or /sup 15/N dilution. The merits of each technique are discussed, and it is suggested that the (/sup 15/N)ammonium oxidation method should be used in conjunction with the (/sup 14/C)bicarbonate incorporation method.

  4. Airborne mapping of shallow water bathymetry in the optically complex waters of the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Vahtmäe, Ele; Kutser, Tiit

    2016-04-01

    Accurate determination of the water depth is important for marine spatial planning, producing maritime charts for navigation, seabed morphology studies, and carrying out different activities in the coastal waters. Bathymetric data are lacking foremost in the shallow water regions as those areas are often inaccessible to the hydrographic ships carrying out echo sounding measurements. Remote sensing technology can be used as an alternative for shallow water bathymetry mapping. Varieties of empirical methods have been proposed for bathymetry retrieval, where the relationship between remotely sensed radiance of the water body and the water depth at sampled locations was established empirically. Two most widely used depth derivation methods, the linear band model proposed by Lyzenga (1978, 1985, 2006), and the log-transformed band ratio model proposed by Stumpf et al. (2003), were applied to the different preprocessing level airborne Hyspex hyperspectral images from the optically complex Baltic Sea area and evaluated for accuracy. Results showed that the Lyzenga linear band model outperformed the Stumpf log-transformed band ratio model. The best results were achieved with the atmospherically corrected images. The application of glint correction did not improve, but even reduced the accuracy of bathymetric maps.

  5. Evaluation of a chemical munition dumpsite in the Baltic Sea based on geophysical and chemical investigations.

    PubMed

    Missiaen, Tine; Söderström, Martin; Popescu, Irina; Vanninen, Paula

    2010-08-01

    This paper discusses the results of geophysical and chemical investigations carried out in a chemical munition dumpsite in the southern Baltic Sea, east of the island of Bornholm. After WW2 over 32,000 tons of chemical war material was dumped here including shells and bombs as well as small drums and containers. The geophysical investigations combined very-high-resolution seismics and gradiometric measurements. The results indicate the presence of a large number of objects buried just below the seafloor. The size of the objects and their distribution, with a marked increase in density towards the center of the dumpsite, suggests that we are dealing with dumped war material. Sediment and near-bottom water samples, taken within the dumpsite and in the surrounding area, were analysed for the presence of various chemical warfare agents (CWA) including Adamsite, Clark, sulphur mustard, tabun, chlorobenzene and arsine oil. The results indicate a widespread contamination that reaches far beyond the dumpsite boundary. CWA degradation products were found in most of the sediment samples. The contamination was mostly related to arsenic containing compounds; only one sample indicated the presence of sulfur mustard. Although the correlation between detected objects and CWA concentrations is not always straightforward, the overall results suggest that a lot of the dumped war material is leaking and that over the years the contamination has reached the seafloor sediments. PMID:20593551

  6. Seagrass vegetation and meiofauna enhance the bacterial abundance in the Baltic Sea sediments (Puck Bay).

    PubMed

    Jankowska, Emilia; Jankowska, Katarzyna; Włodarska-Kowalczuk, Maria

    2015-09-01

    This study presents the first report on bacterial communities in the sediments of eelgrass (Zostera marina) meadows in the shallow southern Baltic Sea (Puck Bay). Total bacterial cell numbers (TBNs) and bacteria biomass (BBM) assessed with the use of epifluorescence microscope and Norland's formula were compared between bare and vegetated sediments at two localities and in two sampling summer months. Significantly higher TBNs and BBM (PERMANOVA tests, P < 0.05) were recorded at bottom covered by the seagrass meadows in both localities and in both sampling months. The relationships between bacteria characteristics and environmental factors (grain size, organic matter, photopigments in sediments), meiofauna and macrofauna densities, as well as macrophyte vegetation characteristics (shoot density, phytobenthos biomass) were tested using PERMANOVA distance-based linear model (DISTLM) procedures and showed that the main factors explaining bacteria characteristics are bottom type (vegetated vs. unvegetated) and meiofauna density. These two factors explained together 48.3% of variability in TBN and 40.5% in BBM, and their impacts did not overlap (as indicated by DISTLM sequential tests) demonstrating the different natures of these relationships. The effects of seagrass were most probably related to the increase of organic matter and providing habitat while higher numbers of meiofauna organisms may have stimulated the bacterial growth by increased grazing. PMID:26178839

  7. Airborne mapping of shallow water bathymetry in the optically complex waters of the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Vahtmäe, Ele; Kutser, Tiit

    2016-04-01

    Accurate determination of the water depth is important for marine spatial planning, producing maritime charts for navigation, seabed morphology studies, and carrying out different activities in the coastal waters. Bathymetric data are lacking foremost in the shallow water regions as those areas are often inaccessible to the hydrographic ships carrying out echo sounding measurements. Remote sensing technology can be used as an alternative for shallow water bathymetry mapping. Varieties of empirical methods have been proposed for bathymetry retrieval, where the relationship between remotely sensed radiance of the water body and the water depth at sampled locations was established empirically. Two most widely used depth derivation methods, the linear band model proposed by Lyzenga (1978, 1985, 2006), and the log-transformed band ratio model proposed by Stumpf et al. (2003), were applied to the different preprocessing level airborne Hyspex hyperspectral images from the optically complex Baltic Sea area and evaluated for accuracy. Results showed that the Lyzenga linear band model outperformed the Stumpf log-transformed band ratio model. The best results were achieved with the atmospherically corrected images. The application of glint correction did not improve, but even reduced the accuracy of bathymetric maps.

  8. The occurrence of endocrine disrupting compounds in off-shore sediments from the southern Baltic Sea.

    PubMed

    Ruczyńska, Wiesława; Szlinder-Richert, Joanna; Drgas, Aleksander

    2016-09-14

    This paper presents the study on the occurrence and spatial distribution of polybrominated diphenyl ethers (PBDEs), butyltin compounds (BTCs), bisphenol A (BPA), and alkylphenols (APs) in sediments. The study focused mainly on off-shore surface sediments collected from the southern Baltic Sea. The pollutant concentrations were as follows:

  9. Use of biliary PAH metabolites as a biomarker of pollution in fish from the Baltic Sea.

    PubMed

    Vuorinen, Pekka J; Keinänen, Marja; Vuontisjärvi, Heta; Barsiene, Janina; Broeg, Katja; Förlin, Lars; Gercken, Jens; Kopecka, Justyna; Köhler, Angela; Parkkonen, Jari; Pempkowiak, Janusz; Schiedek, Doris

    2006-01-01

    During field campaigns of the BEEP project (Biological Effects of Environmental Pollution in Marine Coastal Ecosystems) in 2001-2002, metabolites of polycyclic aromatic hydrocarbons (PAHs) were determined in bile samples from three fish species, flounder (Platichthys flesus), perch (Perca fluviatilis) and eelpout (Zoarces viviparus), from four separate areas in the Baltic Sea. Two determination methods were applied: fixed wavelength fluorescence (FF) for pyrene-type metabolites and high-performance liquid chromatography with fluorescence detection (HPLC). There was a good correlation between the FF method and 1-OH pyrene determined by HPLC. Normalisation of the FF data for absorbance at 380 nm or bile protein concentrations greatly increased variance in one third and decreased it in two thirds of the cases and resulted in a loss of significant differences (protein normalisation) between the sampling stations, but normalisation of the HPLC data had little effect on the results. The biliary PAH metabolite content was usually higher in males than in females. In perch and eelpout the biliary PAH contents were at similar levels, whereas in flounder the levels were lower. The sampling areas arranged in decreasing order of biliary PAH contents were: Wismar Bay > Gulf of Gdansk > Lithuanian coast > Kvadofjärden (reference area). It is concluded that FF with un-normalised data is a reliable and simple method for monitoring purposes and only one sex of a selected species should be used.

  10. Analysis of radium isotopes and radon in a groundwater affected coastal area of the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Purkl, S.; Eisenhauer, A.

    2003-04-01

    All four naturally occurring radium isotopes (223Ra, 224Ra, 226Ra, 228Ra) and 222Rn in the groundwater affected Eckernförder Bay (EB) of the Baltic Sea (Germany) were measured using alpha-spectrometry and liquid scintillation (LS) counting. The applied analytical methods are optimally adapted for extensive field surveillance of short lived radiotracers. Dispersive physical mixing acting over time scales in the order of days is responsible for the distribution of 223Ra, 224Ra and 222Rn in EB. The distribution of these natural tracers is controlled by the strength of the sedimentary source, the influence of direct groundwater input, the dispersive mixing coefficient in the water column and their own radioactive decay. From the inventory of 222Rn in the EB the obtained groundwater discharge rate can be estimated. In order to balance the inventory of 223Ra and 224Ra a source other than groundwater seepage has to responsible for almost all of the 224Ra and 223Ra inventory of the EB. Diffusion from sediments seems to be the major source for short-lived Ra isotopes in the lower water column of EB.

  11. Selective inhibition of cancer cells' proliferation by compounds included in extracts from Baltic Sea cyanobacteria.

    PubMed

    Felczykowska, Agnieszka; Pawlik, Anna; Mazur-Marzec, Hanna; Toruńska-Sitarz, Anna; Narajczyk, Magdalena; Richert, Malwina; Węgrzyn, Grzegorz; Herman-Antosiewicz, Anna

    2015-12-15

    Cyanobacteria are a rich source of biologically active compounds used in pharmacology and biotechnology. Due to their high capacity of adaptation, which is reflected in the production of diverse metabolites, including toxins, these microorganisms are able to inhabit very different environments. In this work, water and ethanol extracts from 11 cyanobacterial strains derived from the Baltic Sea (Microcystis, Synechocystis, Leptolyngbya, Pseudanabaena, Lyngbya, Phormidium, Nodularia and Anabaena genera) were screened for anticancer activity. MCF-7 human breast cancer and HeLa cervical cancer cell lines, as well as HDFa normal human fibroblasts, were used. Three extracts derived from Pseudanabaena sp., Pseudanabaena cf. galeata and Microcystis aeruginosa revealed potent and selective antiproliferative activities against cancer cells. The mechanism of the anticancer activity was explored in MCF-7 cells, and was found to rely on the inhibition of the pro-survival Akt kinase and induction of cell death. The peptide profiles of selected cyanobacterial extracts were determined using LC-MS/MS, and classes of bioactive compounds that might be potentially responsible for the observed anticancer activities are presented.

  12. [Sulfate-Reducing Bacterial Communities in the Water Column of the Gdansk Deep (Baltic Sea)].

    PubMed

    Korneeva, V A; Pimenov, N V; Krek, A V; Tourova, T P; Bryukhanov, A L

    2015-01-01

    Biodiversity of sulfate-reducing bacterial communities in the water column of the Gdansk Deep, Baltic Sea, where H2S had been detected in near-bottom layers, was analyzed by PCR with primers for the 16S rRNA genes of six major phylogenetic subgroups of sulfate-reducing bacteria (SRB). Using denaturing gradient gel electrophoresis followed by sequencing, the nucleotide sequences of reamplified dsrB gene fragments from investigated water samples were determined. For the first time the presence of nucleotide sequences of the dsrB gene was detected by PCR in the water samples from all hydrochemical layers, including subsurface oxic waters. The presence of the 16S rRNA genes of representatives of Desulfotomaculum, Desulfococcus-Desulfonema-Desulfosarcina, and Desulfovibrio-Desulfomicrobium SRB subgroups was also revealed throughout the water column of the Gdansk Deep. Analysis of translated amino acid sequences encoded by the dsrB gene demonstrated the highest homology with the relevant sequences of uncultured SRB from various marine habitats.

  13. Chemical and Biological Composition of Suspended Particles and Aggregates in the Baltic Sea in Summer (1999)

    NASA Astrophysics Data System (ADS)

    Engel, A.; Meyerhöfer, M.; von Bröckel, K.

    2002-11-01

    Suspended particles and particle aggregates, which formed from concentrated field samples on the roller table, were characterized biologically and chemically along a transect through the Baltic Sea in summer 1999. Phytoplankton composition in field samples was dominated by cyanobacteria, including the filamentous diazotrophic cyanobacteria Aphanizomenon ' baltica', Nodularia spumigena and Anabaena spp. These species formed aggregates together with diatoms, mainly Skeletonema costatum and Chaetoceros spp. and with dinoflagellates, mainly withDinophysis norvegica . Compared to the Redfield ratio, concentration ratios of particulate organic carbon, nitrogen and phosphorus, [POC]:[PON]:[POP], indicated an enrichment of carbon, especially in aggregates. However, regression analysis indicated a higher production rate of PON relative to POP and POC and significant background concentrations of POC. In field samples the concentration of transparent exopolymer particles (TEP) varied around 200 μg Xanthan Equiv. l-1 and comprised a volume fraction of 2-7 ppm and an abundance of about 105 TEP ml-1. TEP were enriched in aggregates as inferred from volume ratios of TEP to conventional particles. It is suggested, that TEP contribute substantially to the background concentration of POC, while the high production rate of PON is attributed to nitrogen fixation of diazotrophic cyanobacteria.

  14. Prehistoric versus modern Baltic Sea cod fisheries: selectivity across the millennia.

    PubMed

    Limburg, Karin E; Walther, Yvonne; Hong, Bongghi; Olson, Carina; Storå, Jan

    2008-12-01

    Combining Stone Age and modern data provides unique insights for management, extending beyond contemporary problems and shifting baselines. Using fish chronometric parts, we compared demographic characteristics of exploited cod populations from the Neolithic Period (4500 BP) to the modern highly exploited fishery in the central Baltic Sea. We found that Neolithic cod were larger (mean 56.4 cm, 95% confidence interval (CI)+/-0.9) than modern fish (weighted mean length in catch =49.5+/-0.2 cm in 1995, 48.2+/-0.2 cm in 2003), and older (mean ages=4.7+/-0.11, 3.1+/-0.02 and 3.6+/-0.02 years for Neolithic, 1995, and 2003 fisheries, respectively). Fishery-independent surveys in 1995 and 2003 show that mean sizes in the stock are 16-17 cm smaller than reflected in the fishery, and mean ages approximately 1-1.5 years younger. Modelled von Bertalanffy growth and back-calculated lengths indicated that Neolithic cod grew to smaller asymptotic lengths, but were larger at younger ages, implying rapid early growth. Very small Neolithic cod were absent and large individuals were rare as in modern times. This could be owing to selective harvests, the absence of small and large fish in the area or a combination. Comparing modern and prehistoric times, fishery selection is evident, but apparently not as great as in the North Atlantic proper.

  15. Long term changes in the status of coastal fish in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Bergström, L.; Heikinheimo, O.; Svirgsden, R.; Kruze, E.; Ložys, L.; Lappalainen, A.; Saks, L.; Minde, A.; Dainys, J.; Jakubavičiūtė, E.; Ådjers, K.; Olsson, J.

    2016-02-01

    Management for sustainable coastal ecosystems is benefited by coherent large scale status assessments to support the identification of measures, but these efforts may be challenged by both data availability and natural biogeographical variation. Coastal fish are a resource for commercial and recreational fisheries as well as significant contributors to coastal ecosystem functioning, by linking lower and higher levels of the food web. This study addresses long term changes in coastal fish communities at Baltic Sea regional scale, in order to identify overall trends and support the operationalization of large scale status assessments of marine biota. The study was focused on two indicators representing the functional groups of Piscivores, which are attributed to changes in food web processes including predation/fisheries, and Cyprinids, which are associated with eutrophication. The indicators were assessed for trends within ten-year intervals, using data combined from national monitoring programs during 1991-2013. The results showed predominantly declining trends in Piscivores and of increases in Cyprinids during the studied three decades, both indicative of a deteriorating status. The pattern was however reversed in the most recent years. Similar results among adjacent areas were identified in some cases, but overall differences at local scale were high, indicating strong influence of local processes. The results suggest that coordinated local measures in order to abate cumulative effects are a preferred way of improving the overall status of coastal fish. The latest studied time intervals were the overall most stable and could be considered as potential baseline years for upcoming regional assessments.

  16. The occurrence of endocrine disrupting compounds in off-shore sediments from the southern Baltic Sea.

    PubMed

    Ruczyńska, Wiesława; Szlinder-Richert, Joanna; Drgas, Aleksander

    2016-09-14

    This paper presents the study on the occurrence and spatial distribution of polybrominated diphenyl ethers (PBDEs), butyltin compounds (BTCs), bisphenol A (BPA), and alkylphenols (APs) in sediments. The study focused mainly on off-shore surface sediments collected from the southern Baltic Sea. The pollutant concentrations were as follows:

  17. Comparison of three airborne laser bathymetry data sets for monitoring the German Baltic Sea Coast

    NASA Astrophysics Data System (ADS)

    Song, Yujin; Niemeyer, Joachim; Ellmer, Wilfried; Soergel, Uwe; Heipke, Christian

    2015-10-01

    Airborne laser bathymetry (ALB) can be used for hydrographic surveying with relative high resolution in shallow water. In this paper, we examine the applicability of this technique based on three flight campaigns. These were conducted between 2012 and 2014 close to the island of Poel in the German Baltic Sea. The first data set was acquired by a Riegl VQ-820-G sensor in November 2012. The second and third data sets were acquired by a Chiroptera sensor of Airborne Hydrography AB in September 2013 and May 2014, respectively. We examine the 3D points classified as seabed under different conditions during data acquisition, e.g. the turbidity level of the water and the flight altitude. The analysis comprises the point distribution, point density, and the area coverage in several depth levels. In addition, we determine the vertical accuracy of the 3D seabed points by computing differences to echo sounding data. Finally, the results of the three flight campaigns are compared to each other and analyzed with respect to the different conditions during data acquisition. For each campaign only small differences in elevation between the laser and the echo sounding data set are observed. The ALB results satisfy the requirements of IHO Standards for Hydrographic Surveys (S-44) Order 1b for several depth intervals.

  18. Spatial distribution of carbonaceous aerosol in the southeastern Baltic Sea region (event of grass fires)

    NASA Astrophysics Data System (ADS)

    Dudoitis, Vadimas; Byčenkienė, Steigvilė; Plauškaitė, Kristina; Bozzetti, Carlo; Fröhlich, Roman; Mordas, Genrik; Ulevičius, Vidmantas

    2016-05-01

    The aerosol chemical composition in air masses affected by large vegetation fires transported from the Kaliningrad region (Russia) and southeast regions (Belarus and Ukraine) during early spring (March 2014) was characterized at the remote background site of Preila, Lithuania. In this study, the chemical composition of the particulate matter was studied by high temporal resolution instruments, including an Aerosol Chemical Speciation Monitor (ACSM) and a seven-wavelength aethalometer. Air masses were transported from twenty to several hundred kilometres, arriving at the measurement station after approximately half a day of transport. The concentration-weighted trajectory analysis suggests that organic aerosol particles are mainly transported over the Baltic Sea and the continent (southeast of Belarus). Results show that a significant fraction of the vegetation burning organic aerosol is transformed into oxidised forms in less than a half-day. Biomass burning aerosol (BBOA) was quantified from the ACSM data using a positive matrix factorization (PMF) analysis, while its spatial distribution was evaluated using air mass clustering approach.

  19. Internal wave mixing in the Baltic Sea: Near-inertial waves in the absence of tides

    NASA Astrophysics Data System (ADS)

    van der Lee, E. M.; Umlauf, L.

    2011-10-01

    The dynamics of near-inertial motions, and their relation to mixing, is investigated here with an extensive data set, including turbulence and high-resolution velocity observations from two cruises conducted in 2008 (summer) and 2010 (winter) in the Bornholm Basin of the Baltic Sea. In the absence of tides, it is found that the basin-scale energetics are governed by inertial oscillations and low-mode near-inertial wave motions that are generated near the lateral slopes of the basin. These motions are shown to be associated with persistent narrow shear-bands, strongly correlated with bands of enhanced dissipation rates that are the major source of mixing inside the permanent halocline of the basin. In spite of different stratification, near-inertial wave structure, and atmospheric forcing during summer and winter conditions, respectively, the observed dissipation rates were found to scale with local shear and stratification in a nearly identical way. This scaling was different from the Gregg-Henyey-type models used for the open ocean, but largely consistent with the MacKinnon-Gregg scaling developed for the continental shelf.

  20. Benthic re-colonization in post-dredging pits in the Puck Bay (Southern Baltic Sea)

    NASA Astrophysics Data System (ADS)

    Szymelfenig, Maria; Kotwicki, Lech; Graca, Bożena

    2006-07-01

    The stage of benthic re-colonization at a site formed by sand extraction was investigated some 10 years after the cessation of dredging. The examined post-dredging pit is one of five deep (up to 14 m) pits created with a static suction hopper on the sandy, flat and shallow (1-2 m) part of the inner Puck Bay (the southern Baltic Sea). The topography of the dredged area makes a specific trap for different kinds of organic matter. It is created by the small areas of post-dredging pits as compared to their depths. As a result, organic matter accumulation leads to anaerobic conditions and hydrogen sulfide formation. Macrofauna was not found to occur permanently in the deepest part (11 m) of the cup-shaped depression, which was characterized by its small area (0.2 km 2) and steep walls. However, permanent occurrence of meiofauna (max. 180 ind. 10 cm -2, mainly Nematoda) was noted. Undoubtedly, re-colonization of benthic fauna assemblages, typical of shallow and sandy seabed of the Puck Bay, will not follow in a natural way in the area of post-dredging pits. Also, it could not be expected that the re-colonization sequence would result in the formation of a structure similar to that of the natural depression (the Kuźnica Hollow).

  1. Parasite transfer from crustacean to fish hosts in the Lübeck Bight, SW Baltic Sea

    NASA Astrophysics Data System (ADS)

    Zander, C. D.; Groenewold, S.; Strohbach, U.

    1994-03-01

    Four helminth parasites out of 19 species found in the Lübeck Bight, Baltic Sea, were chosen for investigations on the transfer from invertebrate to small-sized fish hosts: larvae of the tapeworms Schistocephalus sp. and Bothriocephalus sp. (Cestoda) living in planktonic copepods as primary hosts; Podocotyle atomon (Digenea) and Hysterothylacium sp. (Nematoda) were found in benthic crustaceans, especially Gammarus spp. These hosts were the prey of 3 gobiid fishes, Gobiusculus flavescens (feeding mainly on plankton), Pomatoschistus minutus (preferring benthos), and P. pictus (feeding more on plankton than benthos). Because the fishes selected smaller sizes of crustaceans, they ingested all stages of the copepods but only the smaller-sized groups of gammarids which were often less infested by parasites. In order to evaluate the probability for a fish to be parasitized by a helminth, an infestation potential index (IP) was calculated. Podocotyle atomon and Hysterothylacium sp. revealed an IP which was far lower in gobies than expected when the prevalences of the previous hosts were taken into consideration. The IP of tapeworm larvae was mainly influenced by the feeding pressure of the gobiid predators, which might change with developmental stage and season. It is concluded that parasite transfer to the next host decreases when sizes of prey and predator differ only moderately. This mechanism can reduce the numbers of parasites transferred to less suitable or wrong hosts.

  2. Seagrass vegetation and meiofauna enhance the bacterial abundance in the Baltic Sea sediments (Puck Bay).

    PubMed

    Jankowska, Emilia; Jankowska, Katarzyna; Włodarska-Kowalczuk, Maria

    2015-09-01

    This study presents the first report on bacterial communities in the sediments of eelgrass (Zostera marina) meadows in the shallow southern Baltic Sea (Puck Bay). Total bacterial cell numbers (TBNs) and bacteria biomass (BBM) assessed with the use of epifluorescence microscope and Norland's formula were compared between bare and vegetated sediments at two localities and in two sampling summer months. Significantly higher TBNs and BBM (PERMANOVA tests, P < 0.05) were recorded at bottom covered by the seagrass meadows in both localities and in both sampling months. The relationships between bacteria characteristics and environmental factors (grain size, organic matter, photopigments in sediments), meiofauna and macrofauna densities, as well as macrophyte vegetation characteristics (shoot density, phytobenthos biomass) were tested using PERMANOVA distance-based linear model (DISTLM) procedures and showed that the main factors explaining bacteria characteristics are bottom type (vegetated vs. unvegetated) and meiofauna density. These two factors explained together 48.3% of variability in TBN and 40.5% in BBM, and their impacts did not overlap (as indicated by DISTLM sequential tests) demonstrating the different natures of these relationships. The effects of seagrass were most probably related to the increase of organic matter and providing habitat while higher numbers of meiofauna organisms may have stimulated the bacterial growth by increased grazing.

  3. Responses of Phyto- and Zooplankton Communities to Prymnesium polylepis (Prymnesiales) Bloom in the Baltic Sea

    PubMed Central

    Gorokhova, Elena; Hajdu, Susanna; Larsson, Ulf

    2014-01-01

    A large bloom of Prymnesium polylepis occurred in the Baltic Sea during the winter 2007 – spring 2008. Based on numerous reports of strong allelopathic effects on phytoplankton exerted by P. polylepis and its toxicity to grazers, we hypothesized that during this period negative correlations will be observed between P. polylepis and (1) main phytoplankton groups contributing to the spring bloom (i.e., diatoms and dinoflagellates), and (2) zooplankton growth and abundance. To test these hypotheses, we analyzed inter-annual variability in phytoplankton and zooplankton dynamics as well as growth indices (RNA∶DNA ratio) in dominant zooplankton in relation to the Prymnesium abundance and biomass. Contrary to the hypothesized relationships, no measurable negative responses to P. polylepis were observed for either the total phytoplankton stocks or the zooplankton community. The only negative response, possibly associated with P. polylepis occurrence, was significantly lower abundance of dinoflagellates both during and after the bloom in 2008. Moreover, contrary to the expected negative effects, there were significantly higher total phytoplankton abundance as well as significantly higher winter abundance and winter-spring RNA∶DNA ratio in dominant zooplankton species in 2008, indicating that P. polylepis bloom coincided with favourable feeding conditions for zooplankton. Thus, primary consumers, and consequently also zooplanktivores (e.g., larval fish and mysids), may benefit from haptophyte blooms, particularly in winter, when phytoplankton is scarce. PMID:25393031

  4. Particle-Associated Differ from Free-Living Bacteria in Surface Waters of the Baltic Sea.

    PubMed

    Rieck, Angelika; Herlemann, Daniel P R; Jürgens, Klaus; Grossart, Hans-Peter

    2015-01-01

    Many studies on bacterial community composition (BCC) do not distinguish between particle-associated (PA) and free-living (FL) bacteria or neglect the PA fraction by pre-filtration removing most particles. Although temporal and spatial gradients in environmental variables are known to shape BCC, it remains unclear how and to what extent PA and FL bacterial diversity responds to such environmental changes. To elucidate the BCC of both bacterial fractions related to different environmental settings, we studied surface samples of three Baltic Sea stations (marine, mesohaline, and oligohaline) in two different seasons (summer and fall/winter). Amplicon sequencing of the 16 S rRNA gene revealed significant differences in BCC of both bacterial fractions among stations and seasons, with a particularly high number of PA operational taxonomic units (OTUs at genus-level) at the marine station in both seasons. "Shannon and Simpson indices" showed a higher diversity of PA than FL bacteria at the marine station in both seasons and at the oligohaline station in fall/winter. In general, a high fraction of bacterial OTUs was found exclusively in the PA fraction (52% of total OTUs). These findings indicate that PA bacteria significantly contribute to overall bacterial richness and that they differ from FL bacteria. Therefore, to gain a deeper understanding on diversity and dynamics of aquatic bacteria, PA and FL bacteria should be generally studied independently. PMID:26648911

  5. Chemical Munitions Search & Assessment-An evaluation of the dumped munitions problem in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Bełdowski, Jacek; Klusek, Zygmunt; Szubska, Marta; Turja, Raisa; Bulczak, Anna I.; Rak, Daniel; Brenner, Matthias; Lang, Thomas; Kotwicki, Lech; Grzelak, Katarzyna; Jakacki, Jaromir; Fricke, Nicolai; Östin, Anders; Olsson, Ulf; Fabisiak, Jacek; Garnaga, Galina; Nyholm, Jenny Rattfelt; Majewski, Piotr; Broeg, Katja; Söderström, Martin; Vanninen, Paula; Popiel, Stanisław; Nawała, Jakub; Lehtonen, Kari; Berglind, Rune; Schmidt, Beata

    2016-06-01

    Chemical Munitions Search & Assessment (CHEMSEA) project has performed studies on chemical weapon (CW) detection, sediment pollution and spreading as well as biological effects of chemical warfare agents (CWAs) dumped in the Baltic Sea. Results suggest that munitions containing CWAs are more scattered on the seafloor than suspected, and previously undocumented dumpsite was discovered in Gdansk Deep. Pollution of sediments with CWA degradation products was local and close to the detected objects; however the pollution range was larger than predicted with theoretical models. Bottom currents observed in the dumpsites were strong enough for sediment re-suspension, and contributed to the transport of polluted sediments. Diversity and density of the faunal communities were poor at the dumping sites in comparison to the reference area, although the direct effects of CWA on benthos organisms were difficult to determine due to hypoxic or even anoxic conditions near the bottom. Equally, the low oxygen might have affected the biological effects assessed in cod and caged blue mussels. Nonetheless, both species showed significantly elevated molecular and cellular level responses at contaminated sites compared to reference sites.

  6. Enhanced accumulation of PCB congeners by Baltic Sea blue mussels, Mytilus edulis, with increased algae enrichment

    SciTech Connect

    Gilek, M.; Bjoerk, M.; Broman, D.; Kautsky, N.; Naef, C.

    1996-09-01

    The objective of this study was to examine if natural variations in the quantity of phytoplankton-derived particulate and dissolved organic carbon influences the accumulation of polychlorinated biphenyls (PCBs) in the tissues of Baltic Sea blue mussels (Mytilus edulis L.). In a laboratory flow-through experiment the authors exposed M. edulis to the technical PCB mixture Aroclor{reg_sign} 1248 for 21 d at three different enrichments of the unicellular green algae Chlamydomonas sp., 0.10, 0.16, and 0.32 mg particulate organic carbon (POC)/L. Tissue and water concentrations were determined for seven PCB congeners and 21-d bioaccumulation factors were calculated against total water concentrations. Contrary to what would be expected, an increase in algae enrichment from 0.10 to 0.32 mg POC/L resulted in an enhanced PCB accumulation by a factor of approx. 2. This increase in PCB accumulation was more pronounced for PCB congeners with lower hydrophobicity. These observations have implications for the design of laboratory accumulation studies and potentially for PCB accumulation and cycling in field populations of suspension-feeding mussels in response to changes in eutrophication status.

  7. Predicting oxygen in small estuaries of the Baltic Sea: a comparative approach

    NASA Astrophysics Data System (ADS)

    Kauppila, Pirkko; Meeuwig, Jessica J.; Pitkänen, Heikki

    2003-08-01

    Coastal eutrophication, manifested as hypoxia and anoxia, is a global problem. Only a few empirical models, however, exist to predict bottom oxygen concentration and percentage saturation from nutrient load or morphometry in coastal waters, which are successfully used to predict phytoplankton biomass both in lakes and in estuaries. Furthermore, hardly any empirical models exist to predict bottom oxygen from land-use. A data set was compiled for 19 estuaries in the northern Baltic Sea, which included oxygen concentration and percentage saturation, water chemistry, estuary morphometry, and land-use characteristics. In regression analyses, bottom oxygen was predicted both as a function of the percentage of watershed under agriculture and of mean depth. These models accounted for ca. 55% of the variation in oxygen. Additionally, oxygen was linked to fetch (diameter of the area in the direction of the prevailing wind), which accounted for 30% of the variation in oxygen. This suggests that shallow Finnish estuaries are wind-sensitive. In 'pits' (sub-thermocline waters of deep basins), near-bottom total nitrogen strongly correlated with oxygen percentage saturation ( R2=0.81). Neither chlorophyll a, total phosphorus nor nutrient loading explained oxygen variation in entire estuaries or in 'pits', probably mainly due to annual sedimentation/sediment-water flux dynamics. On the basis of the results of cross-validation, the models have general applicability among Finnish estuaries.

  8. Turbidity characterizes the reproduction areas of pikeperch ( Sander lucioperca (L.)) in the northern Baltic Sea

    NASA Astrophysics Data System (ADS)

    Veneranta, L.; Urho, L.; Lappalainen, A.; Kallasvuo, M.

    2011-11-01

    The pikeperch ( Sander lucioperca (L.)) is an economically important fish species occurring in the fresh and brackish waters of Europe. To evaluate the distribution and extent of the reproduction areas in the northern Baltic Sea, a field survey was carried out in two separate coastal areas. Presence/absence data were used to develop a geographic information system (GIS)-based predictive spatial distribution model, where high resolution raster maps of the focal environmental variables and a logistic regression equation were used to predict the probability of larval occurrence. The results indicated that the pikeperch reproduction areas are located in the innermost archipelago zone where high water turbidity best explained their presence. Turbidity was related to several other variables such as fetch and depth. Contrary to our preliminary hypothesis, surface water temperatures measured during the survey had no significant effect in the model due to the low spatial variation in the measured values. Since turbidity is possible to determine by remote sensing methods, the probability maps can be cost-effectively extended to more extensive coastal areas with proper validation.

  9. Particle-Associated Differ from Free-Living Bacteria in Surface Waters of the Baltic Sea

    PubMed Central

    Rieck, Angelika; Herlemann, Daniel P. R.; Jürgens, Klaus; Grossart, Hans-Peter

    2015-01-01

    Many studies on bacterial community composition (BCC) do not distinguish between particle-associated (PA) and free-living (FL) bacteria or neglect the PA fraction by pre-filtration removing most particles. Although temporal and spatial gradients in environmental variables are known to shape BCC, it remains unclear how and to what extent PA and FL bacterial diversity responds to such environmental changes. To elucidate the BCC of both bacterial fractions related to different environmental settings, we studied surface samples of three Baltic Sea stations (marine, mesohaline, and oligohaline) in two different seasons (summer and fall/winter). Amplicon sequencing of the 16 S rRNA gene revealed significant differences in BCC of both bacterial fractions among stations and seasons, with a particularly high number of PA operational taxonomic units (OTUs at genus-level) at the marine station in both seasons. “Shannon and Simpson indices” showed a higher diversity of PA than FL bacteria at the marine station in both seasons and at the oligohaline station in fall/winter. In general, a high fraction of bacterial OTUs was found exclusively in the PA fraction (52% of total OTUs). These findings indicate that PA bacteria significantly contribute to overall bacterial richness and that they differ from FL bacteria. Therefore, to gain a deeper understanding on diversity and dynamics of aquatic bacteria, PA and FL bacteria should be generally studied independently. PMID:26648911

  10. The mussel caging approach in assessing biological effects of wastewater treatment plant discharges in the Gulf of Finland (Baltic Sea).

    PubMed

    Turja, Raisa; Lehtonen, Kari K; Meierjohann, Axel; Brozinski, Jenny-Maria; Vahtera, Emil; Soirinsuo, Anna; Sokolov, Alexander; Snoeijs, Pauline; Budzinski, Hélène; Devier, Marie-Hélène; Peluhet, Laurent; Pääkkönen, Jari-Pekka; Viitasalo, Markku; Kronberg, Leif

    2015-08-15

    Biological effects of wastewater treatment plant (WWTP) effluents were investigated in Baltic mussels (Mytilus trossulus) caged for one month 800m and 1100m from the WWTP discharge site and at a reference site 4km away. Significant antioxidant, genotoxic and lysosomal responses were observed close to the point of the WWTP discharge. Passive samplers (POCIS) attached to the cages indicated markedly higher water concentrations of various pharmaceuticals at the two most impacted sites. Modeling the dispersal of a hypothetical passive tracer compound from the WWTP discharge site revealed differing frequencies and timing of the exposure periods at different caging sites. The study demonstrated for the first time the effectiveness of the mussel caging approach in combination with passive samplers and the application of passive tracer modeling to examine the true exposure patterns at point source sites such as WWTP pipe discharges in the Baltic Sea.

  11. Freak waves of different types in the coastal zone of the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Didenkulova, I.; Anderson, C.

    2010-09-01

    We present a statistical analysis of freak waves1 measured during the 203 h of observation on sea surface elevation at a location in the coastal zone of the Baltic Sea (2.7 m depth) during June-July 2008. The dataset contains 97 freak waves occurring in both calm and stormy weather conditions. All of the freak waves are solitary waves, 63% of them having positive shape, 17.5% negative shape and 19.5% sign-variable shape. It is suggested that the freak waves can be divided into two groups. Those of the first group, which includes 92% of the freak waves, have an amplification factor (ratio of freak wave height to significant wave height) which does not vary from significant wave height and has values largely within the range of 2.0 to 2.4; while for the second group, which contain the most extreme freak waves, amplification factors depend strongly on significant wave height and can reach 3.1. Analysis based on the Generalised Pareto distribution is used to describe the waves of the first group and lends weight to the identification of the two groups. It is suggested that the probable mechanism of the generation of freak waves in the second group is dispersive focussing. The time-frequency spectra of the freak waves are studied and dispersive tracks, which can be interpreted as dispersive focussing, are demonstrated. 1 taken to be waves whose height is 2 or more times greater than the significant wave height

  12. Bacterioneuston Community Structure in the Southern Baltic Sea and Its Dependence on Meteorological Conditions▿†

    PubMed Central

    Stolle, Christian; Labrenz, Matthias; Meeske, Christian; Jürgens, Klaus

    2011-01-01

    The bacterial community in the sea surface microlayer (SML) (bacterioneuston) is exposed to unique physicochemical properties and stronger meteorological influences than the bacterial community in the underlying water (ULW) (bacterioplankton). Despite extensive research, however, the structuring factors of the bacterioneuston remain enigmatic. The aim of this study was to examine the effect of meteorological conditions on bacterioneuston and bacterioplankton community structures and to identify distinct, abundant, active bacterioneuston members. Nineteen bacterial assemblages from the SML and ULW of the southern Baltic Sea, sampled from 2006 to 2008, were compared. Single-strand conformation polymorphism (SSCP) fingerprints were analyzed to distinguish total (based on the 16S rRNA gene) and active (based on 16S rRNA) as well as nonattached and particle-attached bacterial assemblages. The nonattached communities of the SML and ULW were very similar overall (similarity: 47 to 99%; mean: 88%). As an exception, during low wind speeds and high radiation levels, the active bacterioneuston community increasingly differed from the active bacterioplankton community. In contrast, the particle-attached assemblages in the two compartments were generally less similar (similarity: 8 to 98%; mean: 62%), with a strong variability in the active communities that was solely related to wind speed. Both nonattached and particle-attached active members of the bacterioneuston, which were found exclusively in the SML, were related to environmental clones belonging to the Cyanobacteria, Bacteroidetes, and Alpha-, Beta-, and Gammaproteobacteria originally found in diverse habitats, but especially in water columns. These results suggest that bacterioneuston communities are strongly influenced by the ULW but that specific meteorological conditions favor the development of distinctive populations in the air-water interface. PMID:21478321

  13. Application of a three-dimensional hydrodynamic model to the Himmerfjärden, Baltic Sea

    NASA Astrophysics Data System (ADS)

    Sokolov, Alexander

    2014-05-01

    Himmerfjärden is a coastal fjord-like bay situated in the north-western part of the Baltic Sea. The fjord has a mean depth of 17 m and a maximum depth of 52 m. The water is brackish (6 psu) with small salinity fluctuation (±2 psu). A sewage treatment plant, which serves about 300 000 people, discharges into the inner part of Himmerfjärden. This area is the subject of a long-term monitoring program. We are planning to develop a publicly available modelling system for this area, which will perform short-term forecast predictions of pertinent parameters (e.g., water-levels, currents, salinity, temperature) and disseminate them to users. A key component of the system is a three-dimensional hydrodynamic model. The open source Delft3D Flow system (http://www.deltaressystems.com/hydro) has been applied to model the Himmerfjärden area. Two different curvilinear grids were used to approximate the modelling domain (25 km × 50 km × 60 m). One grid has low horizontal resolution (cell size varies from 250 to 450 m) to perform long-term numerical experiments (modelling period of several months), while another grid has higher resolution (cell size varies from 120 to 250 m) to model short-term situations. In vertical direction both z-level (50 layers) and sigma coordinate (20 layers) were used. Modelling results obtained with different horizontal resolution and vertical discretisation will be presented. This model will be a part of the operational system which provides automated integration of data streams from several information sources: meteorological forecast based on the HIRLAM model from the Finnish Meteorological Institute (https://en.ilmatieteenlaitos.fi/open-data), oceanographic forecast based on the HIROMB-BOOS Model developed within the Baltic community and provided by the MyOcean Project (http://www.myocean.eu), riverine discharge from the HYPE model provided by the Swedish Meteorological Hydrological Institute (http://vattenwebb.smhi.se/modelarea/).

  14. Spatiotemporal Variations of the 90Sr in the Southern Part of the Baltic Sea over the Period of 2005–2010

    PubMed Central

    Saniewski, Michał

    2013-01-01

    The Baltic Sea is one of the most contaminated seas by the radioactive isotope of strontium in the world; therefore the activity of 90Sr is regularly controlled. Due to that fact, seawater samples for 90Sr determination were collected at 16 stations located in the southern Baltic Sea between 2005 and 2010. In this period average activity of 90Sr was 7.8 Bq m−3 and varied within the range from 3.0 Bq m−3 to 11.9 Bq m−3. Because the higher activity of 90Sr was measured in the Baltic Sea than in the North Sea and rivers, inflows from the North Sea and the riverine runoff decreased 90Sr activity in the Baltic Sea. The average 90Sr activity in the bottom water along the offshore profile was 18% lower than that in the surface water and it was caused by an inflow of salt water from the North Sea. In the Vistula River mouth the average activity of 90Sr in the surface water was about 15% lower than the average activity in the bottom waters. Coastal areas, relatively shallow with good mixing condition in the water column, were characterized by low variability in 90Sr activity. PMID:24324370

  15. Influence of freshwater inflow on the inorganic nutrient and dissolved organic matter within coastal sea ice and underlying waters in the Gulf of Finland (Baltic Sea)

    NASA Astrophysics Data System (ADS)

    Granskog, Mats A.; Kaartokallio, Hermanni; Thomas, David N.; Kuosa, Harri

    2005-10-01

    A study was conducted to measure the biogeochemical characteristics of freshwater plumes underlying Baltic Sea land-fast ice, and the overlying sea ice. A 40-km long transect was conducted in the northern Baltic Sea in March 2003, following a freshwater plume from its source into the fully mixed open-sea area. The spreading of river outflow below the ice resulted in a well-stratified low-salinity surface layer further out than normally occurs in the open-water period. The freshwaters were high in dissolved organic matter (DOC, DON and CDOM), and inorganic nutrients (ammonium, nitrate and silicate), although the levels of phosphate were low. In general these parameters changed concurrently with salinity in such a way that mixing was conservative. The characteristics of the ice varied from the freshwater source to the open water, with increasing salinity and brine volumes (porosity) occurring in the more open-sea stations. Coinciding with the changes in ice properties there was an increase in sea-ice algal growth in the more marine stations along the transect. Biological activity in the ice was largely confined to bottom ice assemblages. In contrast to the conditions in the underlying water, no relationship between salinity, inorganic nutrients and organic matter was observed in the ice. In particular ammonium, phosphate, DOC and DON were present in excess of those levels predicted from the dilution curves, indicating the presence of considerable DOM production by ice assemblages, inorganic nutrient uptake and remineralization within the ice.

  16. Modelling of river plume dynamics in Öre estuary (Baltic Sea) with Telemac-3D hydrodynamic model

    NASA Astrophysics Data System (ADS)

    Sokolov, Alexander

    2016-04-01

    The main property of river plumes is their buoyancy, fresh water discharged by rivers is less dense than the receiving, saline waters. To study the processes of plume formation in case of river discharge into a brackish estuary where salinity is low (3.5 - 5 psu) a three dimensional hydrodynamic model was applied to the Öre estuary in the Baltic Sea. This estuary is a small fjord-like bay in the north part of the Baltic Sea. Size of the bay is about 8 by 8 km with maximum depth of 35 metres. River Öre has a small average freshwater discharge of 35 m3/s. But in spring during snowmelt the discharge can be many times higher. For example, in April 2015 the discharge increased from 8 m3/s to 160 m3/s in 18 days. To study river plume dynamics a finite element based three dimensional baroclinic model TELEMAC - 3D is used. The TELEMAC modelling suite is developed by the National Laboratory of Hydraulics and Environment (LNHE) of Electricité de France (EDF). Modelling domain was approximated by an unstructured mesh with element size varies from 50 to 500 m. In vertical direction a sigma-coordinate with 20 layers was used. Open sea boundary conditions were obtained from the Baltic Sea model HIROMB-BOOS using COPERNICUS marine environment monitoring service. Comparison of modelling results with observations obtained by BONUS COCOA project's field campaign in Öre estuary in 2015 shows that the model plausible simulate river plume dynamics. Modelling of age of freshwater is also discussed. This work resulted from the BONUS COCOA project was supported by BONUS (Art 185), funded jointly by the EU and the Swedish Research Council Formas.

  17. Modelling the 13C and 12C isotopes of inorganic and organic carbon in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Gustafsson, Erik; Mörth, Carl-Magnus; Humborg, Christoph; Gustafsson, Bo G.

    2015-08-01

    In this study, 12C and 13C contents of all carbon containing state variables (dissolved inorganic and organic carbon, detrital carbon, and the carbon content of autotrophs and heterotrophs) have for the first time been explicitly included in a coupled physical-biogeochemical Baltic Sea model. Different processes in the carbon cycling have distinct fractionation values, resulting in specific isotopic fingerprints. Thus, in addition to simulating concentrations of different tracers, our new model formulation improves the possibility to constrain the rates of processes such as CO2 assimilation, mineralization, and air-sea exchange. We demonstrate that phytoplankton production and respiration, and the related air-sea CO2 fluxes, are to a large degree controlling the isotopic composition of organic and inorganic carbon in the system. The isotopic composition is further, but to a lesser extent, influenced by river loads and deep water inflows as well as transformation of terrestrial organic carbon within the system. Changes in the isotopic composition over the 20th century have been dominated by two processes - the preferential release of 12C to the atmosphere in association with fossil fuel burning, and the eutrophication of the Baltic Sea related to increased nutrient loads under the second half of the century.

  18. Utö Atmospheric and Marine Research Station - a new Baltic Sea ICOS-site for sea-atmosphere research

    NASA Astrophysics Data System (ADS)

    Laakso, Lauri; Laurila, Tuomas; Mäkelä, Timo; Hatakka, Juha; Purokoski, Tero; Hietala, Riikka; Roine, Tuomo; Jämsen, Pertti; Kielosto, Sami; Asmi, Eija; Lonka, Harry; Alenius, Pekka; Drebs, Achim; Seppälä, Jukka; Ylöstalo, Pasi; Tamminen, Timo

    2015-04-01

    Atmospheric research has developed a concept of focused, multidisciplinary, automated observation platforms with continuous high time resolution observations. This approach containing state-of-the-art equipment has enabled research on physical, chemical and biological processes and seasonal variability and showed up new, previously unknown phenomena. New technical and engineering solutions allowing, such approach is also state-of-the-art in marine research through projects like US Ocean Observatories Initiative (OOI), European Multidisciplinary Seafloor Observatory (EMSO), JERICO-NEXT and Japanese DONET. At the Baltic Sea, on Island of Utö (59° 46'50N, 21° 22'23E), Finnish Meteorological Institute has observed meteorology since 1881, marine parameters since 1900 and a diversity of atmospheric chemical and physical variables since 1980. Recent years the stations has also been upgraded with aerosol observations, and together with Finnish Environment Institute, on marine observations. The current and observations under construction at Utö Atmospheric and Marine Research Station (en.ilmatieteenlaitos.fi/uto. Marine observations: surface waves, ice-cover radar, temperature and salinity and oxygen at different depths, chlorophyll, cyanobacteria, underwater flows, turbidity, pCO2 and nutrients. Atmospheric observations: T, WS, WD, visibility, cloud height, boundary layer wind profiles and turbulence, weather and underwater camera, aerosol particle size distributions, aerosol light scattering and absorption, SO2, NOx, CO, O3, CO2, CH4, sea-atmosphere CO2- and heat fluxes. In our presentation, we present for the first time some 100 years of climate relevant atmospheric and marine observations from Utö.

  19. Validation of ERA-Interim precipitation estimates over the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Bumke, Karl

    2015-04-01

    The closing of the energy and water budgets of the Baltic Sea is only possible, when beside an accurate knowledge of the in- and outflows through the Danish Sounds, evaporation and precipitation are exactly known. Due to a lack of in-situ observations of precipitation over sea it is common to use data from numerical models or remote sensing, although e.g. Andersson et al. (2011) pointed out that even state-of-the-art satellite retrievals and reanalysis data sets still disagree with respect to amounts or variability compared to observations. In our study we validate ERA-Interim reanalysis data of total precipitation against ten years (1995-2004) of in-situ precipitation measurements onboard of ships. ERA-Interim data consist of three hourly surface forecast fields on a regular grid with a 0.75° x 0.75° resolution, which are initiated twice a day. Observations within the forecast period were collocated to the surrounding grid points of the reanalysis data. Since ship rain gauges are only suitable to measure rain, only measurements at air temperatures above 4°C were taken into account. The number of collocated data exceeds 200000. Comparing all data gives a good agreement of mean rain rates of measurements and reanalysis data. But a closer look reveals an underestimation of ERA-Interim precipitation in spring and an overestimation in autumn, related to atmospheric stability. The atmospheric stability is linked to turbulent heat fluxes and indeed it is found that ERA-Interim underestimates rain rates by up to 40 percent under situations with low latent heat fluxes and overestimates rain rates strongly up to about 150 percent under conditions with high latent heat fluxes. To ensure that this is not an artefact due to uncertainties in ERA-Interim fields of evaporation, meteorological data of ships have been extracted from the marine meteorological data archive of the Seewetteramt Hamburg, and were also collocated to the reanalysis data. These data were used to derive

  20. Seasonal Groundwater Flowdynamic within the Freshwater Lense in Coastal Dune on Hiddensee Island/Baltic Sea

    NASA Astrophysics Data System (ADS)

    Dötschel, Christian; Meyer, Tammo; Schafmeister, Maria-Theresia; Weise, Stephan M.

    2014-05-01

    Freshwater bodies on islands serve as precious drinking water supply. The delicate equilibrium between ocean and groundwater with respect to salinity in the coastal dune zone of Hiddensee Island preserves a unique plant diversity in the dune valley heath. Scope of the investigation is to understand the seasonal dynamic of groundwater flow in the freshwater lense by means of geochemical and isotopic analyses. The Island Hiddensee is situated off the western coast of Germany's biggest island Rügen in the Baltic