Zooplankton oxygen consumption and nutrient release in relation to species composition, animals size and enviromental conditions in the Baltic Sea during May and August

[EN] Zooplankton metabolism in terms of oxygen consumption and ñutrient reléase (ammonia, phosphate) were measiu'ed in the Baltic Sea, a températe área with high envirormiental changes both in space and in time. Plankton of the surface layer were analysed with balance measurements in 4 size classes between 50 and 1000 nm during spring in 1988, 1990 and 1991, in summer 19^8 and 1990 as well. The use of electrón transport system (ETS), and the Glutamate Dehydrogenase (GDH) activity as indicators for respiration and ammonia reléase respectively, enlarged the data density and made a three dimensional resolution available (May 1990, 1991). Data are in the range of the latitudinal dependend magnitude. They reflect slight interannual, more seasonal and regional aspects. Animáis size, temperature, food concentration, and species composition influence the specific rates

Archaeological Baltic amber: degradation mechanisms and conservation measures

The aim of this project was to achieve a deep understanding of the mechanisms by which Baltic amber degrades, in order to develop techniques for preventive conservation of archaeological amber objects belonging to the National Museum of Denmark’s collections. To examine deterioration of Baltic amber, a starting point was to identify and monitor surface and bulk properties which are affected during degradation. The way to operate consisted of the use of accelerated ageing to initiate degradation of raw Baltic amber samples in different conditions of relative humidity, oxygen exposure or pH and, successively, of the use of non/micro-destructive techniques to identify and quantify changes in visual, chemical and structural properties. A large piece of raw Baltic amber was used to prepare several test samples for two different kinds of accelerated ageing: thermal-ageing and photo-ageing. During the ageing, amber samples were regularly examined through several analytical techniques related to different information: appearance/colour change by visual examination, photography and colorimetry; chemical change by infrared spectroscopy, Raman spectroscopy and elemental analysis; rate of oxidation by oxygen measurement; qualitative analysis of released volatiles by gas chromatography – mass spectrometry. The obtained results were analysed through both critical evaluation and statistical study. After the interpretation of the achieved data, the main relations between amber and environmental factors during the degradation process became clearer and it was possible to identify the major pathways by which amber degrades, such as hydrolysis of esters into alcohols and carboxylic acids, thermal-oxidation and photo-oxidation of terpenoid components, depolymerisation and decomposition of the chemical structure. At the end it was possible to suggest a preventive conservation strategy based on the control of climatic, atmospheric and lighting parameters in the environment where Baltic amber objects are stored and displayed.

Divergence patterns in Fucus seaweeds (Phaeophyceae) in the northern Baltic Sea and in the Tjongspollen area

To be able to interpret patterns of biodiversity it is important to understand the processes by which new species evolve and how closely related species remain reproductively isolated and ecologically differentiated. Divergence and differentiation can vary during speciation and it can be seen in different stages. Groups of closely related taxa constitute important case studies to understand species and new biodiversity formation. However, it is important to assess the divergence among them at different organismal levels and from an integrative perspective. For this purpose, this study used the brown seaweeds genus Fucus as a model to study speciation, as they constitute a good opportunity to study divergence at different stages. We investigated the divergence patterns in Fucus species from two marginal areas (northern Baltic Sea and the Tjongspollen area), based on phenetic, phylogenetic and biological taxonomical criteria that are respectively characterised by algal morphology, allele frequencies of five microsatellite loci and levels of secondary polyphenolic compounds called phlorotannins. The results from this study showed divergence at morphological and genetic levels to certain extent but complete lack of divergence at biochemical level (i.e. constitutive phlorotannin production) in the Baltic Sea or Norway. Morphological divergence was clearly evident in Tjongspollen (Norway) among putative taxa as they were identified in the field and this divergence corresponds with their neutral genetic divergence. In the Baltic, there are some distinguishable patterns in the morphology of the swedish and finnish individuals according to locality to certain extent but not among putative taxa within localities. Likewise, these morphological patterns have genetic correspondence among localities but not within each locality. At the biochemical level, measured by the phlorotannin contents there were neither evidence of divergence in Norway or the Baltic Sea nor any discernable aggregation pattern among or within localities. Our study have contributed with further understanding of the Baltic Sea Fucus system and its intriguingly rapid and recent divergence as well as of the Tjongspollen area systems where formally undescribed individuals have been observed for the first time; in fact they appear largely differentiated and they may well warrant a new species status. In current times, climate change threatens, peripheral ecosystems, biodiversity, and increased knowledge of processes generating and maintaining biodiversity in those ecosystems seem particularly important and needed.

Molybdenum isotope fractionation in pelagic euxinia: Evidence from the modern Black and Baltic Seas

Here we present stable isotope data for vertical profiles of dissolved molybdenum of the modern euxinic water columns of the Black Sea and two deeps of the Baltic Sea. Dissolved molybdenum in all water samples is depleted in salinity-normalized concentration and enriched in the heavy isotope (δ98Mo values up to + 2.9‰) compared to previously published isotope data of sedimentary molybdenum from the same range of water depths. Furthermore, δ98Mo values of all water samples from the Black Sea and anoxic deeps of the Baltic Sea are heavier than open ocean water. The observed isotope fractionation between sediments and the anoxic water column of the Black Sea are in line with the model of thiomolybdates that scavenge to particles under reducing conditions. An extrapolation to a theoretical pure MoS42− solution indicates a fractionation constant between MoS42− and authigenic solid Mo of 0.5 ± 0.3‰. Measured waters with all thiomolybdates coexisting in various proportions show larger but non-linear fractionation. The best explanation for our field observations is Mo scavenging by the thiomolybdates, dominantly — but not exclusively — present in the form of MoS42−. The Mo isotopic compositions of samples from the sediments and anoxic water column of the Baltic Sea are in overall agreement with those of the Black Sea at intermediate depth and corresponding sulphide concentrations. The more dynamic changes of redox conditions in the Baltic deeps complicate the Black Sea-derived relationship between thiomolybdates and Mo isotopic composition. In particular, the occasional flushing/mixing, of the deep waters, affects the corresponding water column and sedimentary data. δ98Mo values of the upper oxic waters of both basins are higher than predicted by mixing models based on salinity variations. The results can be explained by non-conservative behaviour of Mo under suboxic to anoxic conditions in the shallow bottom parts of the basin, most pronounced on the NW shelf of the Black Sea.

Creation of Computer Simulation Model for Ecological Consequences Prognosis of Toxic Chemicals Discharge from Sunken on Baltic Sea Bottom Weapons"

This study summarises all the accessible data on old German chemical weapons dumped in the Baltic Sea. Mr. Goncharov formulated a concept of ecological impact evaluation of chemical warfare agents (CWA) on the marine environment and structured a simulation model adapted to the specific character of the hydrological condition and hydrobiological subjects of the Bornholm Deep. The mathematical model he has created describes the spreading of contaminants by currents and turbulence in the near bottom boundary layer. Parameters of CWA discharge through corrosion of canisters were given for various kinds of bottom sediments with allowance for current velocity. He created a method for integral estimations and a computer simulation model and completed a forecast for CWA "Mustard", which showed that in normal hydrometeorological conditions there are local toxic plumes drifting along the bottom for a distance of up to several kilometres. With storm winds the toxic plumes from separate canisters interflow and lengthen and can reach fishery areas near Bornholm Island. When salt water from the North Sea flows in, the length of toxic zones can increase up to and over 100 kilometres and toxic water masses can spread into the northern Baltic. On this basis, Mr. Goncharov drew up recommendations to reduce dangers for human ecology and proposed the creation of a special system for the forecasting and remote sensing of the environmental conditions of CWA burial places.

Development of Socio-Economic Behaviour and Attitudes of Baltic Nationalities: Perspectives for Integration with Europe

This project is the third stage of a comparative research project, The New Baltic Barometer, which was carried out simultaneously with the "New Democracies Barometer" of the Paul Lazerfeld Society (Vienna) and The Russian Barometer. It studied the opinion and behaviour of the largest Baltic ethnic groups (Estonians, Latvians, Lithuanians). The main focus was on the attitudes of Baltic residents towards the changes in the economic and political system, attitudes towards political values, political trust, and attitudes to the Baltic countries joining the European Union. An analysis of macroeconomic indicators of the Baltic states made it possible to deduce the link between the country's economic development, and satisfaction with the political regime and attitudes towards democratic values. The study analysed the conditions for the democratisation of society, i.e. the development of culture and public opinion in the Baltic states. Attention was also paid to the development of a social network of individuals, showing the transition from informal networks to impersonal institutions. The group concluded that the participation of residents in formal organisations, NGOs in particular, considerably fosters political trust and also increases political efficacy. Participation in formal organisations also reduces the importance of esteem for an authoritarian leader.

Detection of prion protein gene polymorphisms in Baltic breeds of sheep

A total of 167 sheep belonging to the Estonian whiteheaded mutton, Estonian blackheaded mutton, Lithuanian coarsewool native, Lithuanian blackface and Latvian darkheaded mutton breeds, and a population of sheep kept isolated on the Estonian island of Ruhnu, were sequence-analysed for polymorphisms in the prion protein (PrP) gene, to determine their genotype and the allele frequencies of polymorphisms in PrP known to confer resistance to scrapie. A 939 base pair fragment of exon 3 from the PrP gene was amplified by pcr and analysed by direct sequencing. For animals showing polymorphism at two nucleotide positions, both haplotypes of these double-heterozygous genotypes were further verified by pcr cloning and sequence analysis. Known polymorphisms were observed at codons 136, 154 and 171, and six different haplotypes (arr, ahq, arh, ahr, arq and vrq) were determined. On the basis of these polymorphisms, the six populations of sheep possessed the resistant arr haplotype at different frequencies. The high-risk arq haplotype occurred in high frequencies in all six populations, but vrq, the haplotype carrying the highest risk, occurred at low frequencies and in only three of the populations.

Palaeohydrology, fires and vegetation succession in the southern Baltic during the last 7500 years reconstructed from a raised bog based on multi-proxy data

We present the first 7500 yr long multi-proxy record from a raised bog located at the southern Baltic coast, Poland. Testate amoebae, plant macrofossils, pollen and microscopic charcoal were used to reconstruct environmental changes in Pomerania (northern Poland, Kaszuby Lakeland) from a 7-m thick peat archive of Stążki bog dated 5500 BC–AD 1250. We obtained a record of proxies representing different spatial scales: regional vegetation changed simultaneously with local vegetation, and testate amoebae showed a pattern of change similar to that of pollen and plant macrofossils. On the basis of the combined proxies, we distinguished three hydroclimatic stages: moist conditions 5500–3450 BC, drier conditions with regionally increased fires up to 600 BC, and again moist conditions from 600 BC onward. During the drier interval, a first climatic shift to wetter conditions at 1700 BC is indicated by regional pollen as the replacement of Corylus by Carpinus, and locally by, e.g., the increase of Hyalosphenia elegans and mire plants such as Sphagnum sec. Cuspidata. Furthermore, we observed a correlation since 600 BC among the re-expansion of Carpinus (after a sudden decline ca. 950 BC), increased peat accumulation, increase of Hyalosphenia species, and fewer fires, suggesting lower evapotranspiration and a stable high water table in the bog. Fagus started to expand after AD 810 gradually replacing Carpinus, which was possibly due to a gradually more oceanic climate, though we cannot exclude human impact on the forests. Peat accumulation, determined by radiocarbon dating, varied with bog surface wetness. The hydroclimatic phases found in Stążki peatland are similar to moisture changes recorded in other sites from Poland and Europe. This is the first detailed record of hydroclimatic change during the Holocene in the southern Baltic region, so it forms a reference site for further studies on other southern Baltic bogs that are in progress.

The 1872 Baltic Sea storm surge

On 13 November 1872, the Baltic Sea coast from Denmark to Pomerania was devastated by an extreme storm surge caused by high winds. This is still the strongest surge on record, and understanding its development can contribute to improved risk assessment and protection. In this paper we trace this event in sea-level pressure and wind data from the “Twentieth Century Reanalysis” (20CR) and compare the results with other observation-based data sources. The analysis shows that, in the ensemble mean of 20CR, the general development is qualitatively well depicted, but with much reduced strength compared to other data sets. The same is true when selecting the ensemble member with maximum wind speeds.

Annotated record and chemical composition of iron-manganese nodules from the Baltic Sea

Iron-manganese concretions, closely related to lacustrine ores and deep sea manganese nodules, are presently forming in different parts of Gulfs of Bothnia and Finland. They can be divided according to physical form into three distinct groups: (1) round pea-shaped concretions, (2) ring-shaped concrections, and (3) flat sheets and crusts of concretionary material. A definite correlation was found to exist between the form i.e. type of concretions and their chemical composition (Mn/Fe ratio). Trace element concentrations were generally rather high, although not as high as in deep sea manganese nodules. X-ray and DTA was used to study the mineralogy and crystal structure of the concretions. Surface concentrations and geographical distribution of the concretions were estimated on the basis of samples, diving observations and echo-grams.

Clay mineral assemblages in the western Baltic Sea

Surface samples and nine cores from the western Baltic Sea and marginal water bodies were investigated for clay mineral composition. The clay mineral assemblages of recent sediments are rather homogeneous. Variations result mainly from the erosion of different glacial source deposits. High percentages of illite and low kaolinite/chlorite and quartz/feldspar ratios are characteristic for this glacial source. Advection of kaolinite-rich suspensions from the North Sea is believed to account for higher kaolinite/chlorite ratios in the Mecklenburg Bight. A contribution of the rivers Trave and Oder to the western Baltic Sea is indicated by increased smectite values in marginal water bodies. They correspond to increased kaolinite/chlorite and quartz/feldspar ratios. In the main basins the river signal is diluted beyond recognition. Cores from the Arkona, Bornholm and Gotland Basins penetrate through post-Littorina muds and sediments of the Ancylus Lake/Yoldia Sea into Late Glacial sediments of the Baltic Ice Lake. Clay mineral assemblages are characterized by an increase in kaolinite/chlorite ratios from Late Glacial to Holocene sediments, with a distinct shift at each facies change. This allows the distinction and core to core correlation of main lithological units with kaolinite/chlorite ratios. Kaolinite enrichment of Holocene muds corresponds to a brackish-marine facies and may reflect influx of kaolinite-rich suspensions from the North Sea. Cores from the lagoon of the Oderhaff show fluctuations in the contributions of the two main sediment sources: river suspension and glacial deposits during the Late Glacial and Postglacial sequence. Lacustrine sediments, which were deposited prior to 5500 years B.P. are characterized by smectite, kaolinite and quartz from the drainage area of the Oder river. Erosion of coastal and offshore glacial boulder clays with the Littorina transgression supplied a marine component rich in illite, chlorite and feldspars to the brackish muds of the Oderhaff.