Номенклатурные заметки по водорослям, грибам, лишайникам и мохообразным. 9

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 207:13-18 (2000) - doi:10.3354/meps207013 Cyanobacteria blooms in the Gulf of Finland triggered by saltwater inflow into the Baltic Sea M. Kahru1,*, J.-M. Leppänen2, O. Rud3, O. P. Savchuk4 1Scripps Institution of Oceanography, La Jolla, California 92093-0218, USA 2Finnish Institute of Marine Research, PO Box 33, 00931 Helsinki, Finland 3Department of Physical Geography, and 4Department of Systems Ecology, Stockholm University, Stockholm 10691, Sweden *E-mail: mkahru@ucsd.edu ABSTRACT: In the 1980s and 1990s prior to 1995, massive blooms of the diazotrophic cyanobacterium Nodularia spumigena occurred in the Baltic Sea Proper but never extended into the central and eastern Gulf of Finland. The absence of nitrogen-fixing cyanobacteria blooms in parts of the Baltic Sea with a high N:P ratio (e.g. Gulf of Finland) has been explained by their reduced competitive advantage in conditions of P limitation. Starting with the summer of 1995, massive blooms of N. spumigena occurred in the central and eastern Gulf of Finland, as detected by both satellite sensors and in situ monitoring. We propose that the eastward expansion of N. spumigena blooms was triggered by the 1993 saltwater inflow into the Baltic. With the arrival of the saline and oxygen-depleted waters in the Gulf of Finland in 1995, stratification in the bottom layers increased, oxygen concentrations decreased, and increased amounts of phosphate were released from the sediments. The subsequent decrease in the N:P ratio may have caused the reoccurring N. spumigena blooms. KEY WORDS: Cyanobacteria · Nodularia · Nutrients · Gulf of Finland · Baltic Sea Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 207. Online publication date: November 22, 2000 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2000 Inter-Research.

Ferromanganese concretions from the Baltic sea can be divided into three main types based on their abundance, morphology, composition and mode of formation; those from the Gulfs of Bothnia, Finland and Riga, from the Baltic Proper and from the western Belt Sea. Concretions from the Gulf of Bothnia are most abundant in Bothnian Bay where the abundance reaches 15–40 kg m −2 in an area of about 200 km 2 . This is equivalent to about 3 million tonnes of concretions and has led to these deposits being evaluated as an economic resource. These concretions are mainly spheroidal up to 25–30 mm in diameter and are formed in the uppermost water-rich sediment layers at well-oxidized sites. They are most abundant where sedimentation rates are <0.4 mm a −1 . In the Bothnian Sea, flat crusts with low Mn/Fe ratios are widely distributed. Concretions from the Gulf of Finland are abundant in the eastern half of the gulf with a maximum abundance of 18–24 kg m −2 . One area of about 300 km 2 in the Russian sector of the gulf contains about 6 × 10 6 tonnes of spheroidal concretions and is receiving serious attention as an ore resource. These concretions frequently occur in the upper brown oxidized layer of the sediment. Concretions from the Gulf of Riga are most abundant (up to 17 kg m −2 ) around a central depression containing muddy sediments. Spheroidal concretions occur adjacent to the depression and discoidal concretions and crusts further away. Concretions from the Baltic Proper are found mainly around the margins of the deep basins in a depth range 48–103 m. The concretions are mainly discoidal 20–150 mm in diameter and crusts. Their abundance is mainly sporadic and more rarely common to abundant. Locally, abundances of 10–16 kg m −2 are attained. Their formation is the result of the build up of Mn and Fe in the anoxic waters of the deep basins of the Baltic Proper. During major inflows of North Sea water (>100 km 3 ) into the Baltic which occur on average once every 11 years, the anoxic waters are flushed out of the basins. Mn and Fe percipitate out as an unstable gel and are ultimately incorporated into the concretions. The concretions occur mainly on lag deposits in the vicinity of the halocline where strong bottom currents occur. Concretions from Kiel Bay in the western Belt Sea occur in a narrow depth range of 20–28 m at the boundary between sands and mud in zones of active bottom currents. They occur as coatings on molluscs and as spheroidal and discoidal concretions. In Lübeck-Mecklenburg Bay, the concretions are restricted to limited areas where glacial till is exposed through the mud. The formation of the concretions is influenced by the development of summer anoxia which leads to the diagenetic remobilization and lateral transport of Mn. This accounts for the high Mn/Fe ratios of these concretions. Increasing attention is being directed to the use of concretions for the long-term monitoring of heavy-metal pollution in the Baltic. The method shows considerable promise. Zn profiles have already been used to monitor such pollution in concretions from Kiel Bay. However, there remain a number of difficulties such as the lack of knowledge of concretion growth rates, the fragmentary knowledge of the input and fate of heavy metals in the Baltic and the different periods of industrialization in the various pats of the Baltic. Such a monitoring techniques would be of considerable value if the Baltic is going to be cleaned up over the next century. A more detailed evaluation of the mode of formation of the ferromanganese concretions and their uptake of heavy metals would therefore appear to be an important next step in developing a strategy for monitoring pollution in the Baltic Sea.

Dissolved silica budget for the Baltic Sea

The largest massifs of rapakivi granites and related rocks in the western part of the East European Craton are located within the junction area of the Baltic Sea and the Gulfs of Bothnia, Finland and Riga, and along the Gulf of Finland. The rapakivi massifs are of Palaeoproterozoic to Mesoproterozoic (Subjotnian) age, ranging from about 1.67 to 1.5 Ga. In the framework of the Palaeoproterozoic basement tectonics, all major and minor occurrences of rapakivi magmatism are areally limited to within the boundaries of the Svecofennian juvenile crustal domain and its frontiers. The most voluminous of the intrusive bodies are located within the originally thickest (55–65 km) primary part of Svecofennia, where they are coupled with crustal thinning to 40–45 km and mafic underplating anomalies. Only minor rapakivi bodies have intruded the originally thinner (40–45 km) peripheral Palaeoproterozoic crust. The largest igneous subprovinces, namely the Wiborg and Riga-Åland rapakivi massifs, are furthermore connected to specific regional Bouguer gravity anomalies. These anomalies exhibit complex patterns due to the rapakivi-related reworking of the upper mantle and the crust. The bimodal rapakivi and related upper crustal magmatism was systemised in such a way that satellite bodies with minor stock and dike suites became located concentrically around the main igneous bodies. Considering the different ages and locations of the igneous suites, an internal subprovincial distribution occurs in the province. The time of formation for each subprovincial cluster is no longer than 50 m. y. The timing of birth and extinction of the different subprovinces rarely coincide with each other.

<p>Currents in the Baltic Sea are relatively weak and are thus often expected to have a negligible effect on sea surface waves. To evaluate the magnitude of wave–current interactions in the Baltic Sea, we ran the third generation wave model WAM with and without surface currents from the 3D hydrodynamical model Nemo4. The results showed that the currents have a notable effect on wave field only on rare occasions and that the effects are largest in coastal areas of the Baltic Proper, most notably in the western Gotland Basin, and the Gulf of Finland. The simulations showed that the currents in the Baltic Sea can cause differences of significant wave height up to tens of centimeters. More notable effect was the change in the peak of the wave spectrum from swell to wind driven waves and vice versa in some occasions. In our study w<span>e mostly focus on the events of strong wave–current interactions in the northern Baltic Proper and Gulf of Finland as we have measured wave spectra available from these locations. From the comparison with wave buoy measurements we see that implementing surface currents</span> <span>slightly improves the </span><span>m</span><span>odelled peak period in the Gulf of Finland.</span> <span>The Gulf of Finland is of special interest also because a group of ADCP’s were installed close to the wave buoy. The current measurements from these devices can therefore be used to evaluate the accuracy of the currents in the hydrodynamical model. </span></p>

<p>Eutrophication and consequent increase in biomass production and sedimentation of organic material cause oxygen depletion of the deep layers and an increase in hypoxic bottom areas in the Baltic Sea.</p><p>The Baltic Sea – a semi-enclosed brackish sea – has restricted water exchange with the North Sea. High fresh water runoff and sporadic inflows of saline water through the Danish Straits maintain stratification. Seasonal thermocline and quasi-permanent halocline, their vertical location, shape and strength are sensitive to atmospheric forcing and influence the oxygen depletion in the near-bottom layer. Physical processes altering deoxygenation in the three sub-basins of the Baltic Sea (Baltic Proper, Gulf of Finland and Gulf of Riga) are under scope of the present overview. Permanent halocline is present in the deep Baltic Proper, while in the Gulf of Finland, it occasionally vanishes during winter. Complete mixing occurs in each winter in the shallow Gulf of Riga separated from the Baltic Proper by the sill. We show that the bathymetry, combined with physical drivers, causes distinct spatial and temporal patterns of oxygen depletion in the basins. The results presented here are a summary of in-situ measurement campaigns conducted by the research vessel, underwater glider, autonomous vertical profiler and bottom moorings in 2011–2020.</p><p>Large barotropic inflows from the North Sea temporarily ventilate the deep layer of the Central Baltic Proper, but rather intensify hypoxia in the Northern Baltic Proper and the Gulf of Finland. Wind-driven estuarine circulation alterations shape the hypoxic area and volume in the Gulf of Finland considerably. Seaward winds support estuarine circulation and the advection of hypoxic saltier water of the Northern Baltic Proper into the gulf deep layer. The landward wind can reverse estuarine circulation, the collapse of stratification and mixing of the whole water column in winter (when the seasonal thermocline is absent), thus, temporarily improving oxygen conditions in the deep layer of the gulf. Intrusion of cold saltier water of the Baltic Proper over the sill into the Gulf of Riga deep layer strengthens water column stratification and supports hypoxia formation in summer. Such a water exchange regime is related to the northerly wind forced upwelling along the eastern coast of the Baltic Proper. The role of submesoscale processes on vertical mixing and deep layer ventilation is still unclear, and the data of high-resolution in situ measurements in the Baltic Sea is limited yet. Preliminary results from the dedicated underwater glider surveys conducted at the coastal slope of Eastern Baltic Proper in 2019-2020 will be presented.</p>

The features of the interannual dynamics of the surface water temperature in the Central part of the Baltic Sea and in the Gulf of Finland over the past 70 years were analyzed. The total effect of the linear trend and the long-period component on the dispersion of the initial water temperature values in the Central part of the Baltic Sea was 48.4 %, and in the Gulf of Finland was 67.0 %. These two components in 1949–2018 determined the duration of two climatic phases: moderate (1949–1987) with a heat content close to normal and warm (1988–2018). The average rate of temperature increase in the last 31-year period (1988–2018) in the Central part of the Baltic Sea was 0.42 °C per 10 years, while in the Gulf of Finland it was 1.5 times higher. The beginning of the modern period of warming of water masses coincided with the weakening of the meridional type of atmospheric circulation in the North Atlantic and the strengthening of air transport from its water area in the Eastern direction. The increase of water temperature may be one of the reasons for the redistribution of commercial concentrations of herring and sprat in the Baltic Sea, thereby the change in their annual catch in certain ICES sub-divisions of the Central part of the Baltic Sea and the Gulf of Finland was observed.

Stratification-induced hypoxia as a structuring factor of macrozoobenthos in the open Gulf of Finland (Baltic Sea)

The fitness and reproductive output of fishes can be affected by environmental disturbances. In this study, transcriptomics and label-free proteomics were combined to investigate Atlantic salmon (Salmo salar) sampled from three different field locations within the Baltic Sea (Baltic Main Basin (BMB), Gulf of Finland (GoF), and Bothnian Sea (BS)) during marine migration. The expression of several stress related mRNAs and proteins of xenobiotic metabolism, oxidative stress, DNA damage, and cell death were increased in salmon from GoF compared to salmon from BMB or BS. Respiratory electron chain and ATP synthesis related gene ontology-categories were upregulated in GoF salmon, whereas those associated with RNA processing and synthesis, translation, and protein folding decreased. Differences were seen also in metabolism and immune function related gene expression. Comparisons of the transcriptomic and proteomic profiles between salmon from GoF and salmon from BMB or BS suggest environmental stressors, especially exposure to contaminants, as a main explanation for differences. Salmon feeding in GoF are thus “disturbed by hazardous substances”. The results may also be applied in evaluating the conditions of pelagic ecosystems in the different parts of Baltic Sea.

The statistical analysis of the long-term data on the variability of the Baltic Sea level has revealed the complicated character of the wave field structure. The wave field formed by the variable winds and the disturbances of the atmospheric pressure in the Baltic Sea is a superposition of standing oscillations with random phases. The cross spectral analysis of the synchronous observation series of the level in the Gulf of Finland has shown that the nodal lines of the standing dilatational waves are clearly traced with frequencies corresponding to the distance from the nodal line to the top of the gulf (a quarter of the wave length). Several areas of the water basin with clearly expressed resonant properties may be distinguished: the Gulfs of Finland, Riga, and Bothnia, Neva Bay, etc. The estimations of the statistical correlation of the sea level oscillations with the variation of the wind and atmospheric pressure indicate the dominant role of the zonal wind component during the formation of the floods in the Gulf of Finland. The probable reason for the extreme floods in St. Petersburg may be the resonance rocking of the eigenmode oscillations corresponding to the basic fundamental seiche mode of the Gulf of Finland with a period of 27 h when the repeated atmospheric disturbances in the Baltic Sea occur with a period of 1–2 days.

The late summer mass occurrences of cyanobacteria in the Baltic Sea are among the largest in the world. These blooms are rarely monotypic and are often composed of a diverse assemblage of cyanobacteria. The toxicity of the blooms is attributed to Nodularia spumigena through the production of the hepatotoxic nodularin. However, the microcystin hepatotoxins have also been reported from the Baltic Sea on a number of occasions. Recent evidence links microcystin production in the Gulf of Finland directly to the genus Anabaena. Here we developed a denaturing gradient gel electrophoresis (DGGE) method based on the mcyE microcystin synthetase gene and ndaF nodularin synthetase gene that allows the culture-independent discrimination of microcystin- and nodularin-producing cyanobacteria directly from environmental samples. We PCR-amplified microcystin and nodularin synthetase genes from environmental samples taken from the Gulf of Finland and separated them on a denaturing gradient gel using optimized conditions. Sequence analyses demonstrate that uncultured microcystin-producing Anabaena strains are genetically more diverse than previously demonstrated from cultured strains. Furthermore, our data show that microcystin-producing Anabaena are widespread in the open Gulf of Finland. Non-parametric statistical analysis suggested that salinity plays an important role in defining the distribution of microcystin-producing Anabaena. Our results indicate that microcystin-producing blooms are a persistent phenomenon in the Gulf of Finland.

A linear shallow water model was used to study different harmonic oscillations in the Baltic Sea. The model was initialized using a linear sea surface slope from east to west and was hereafter run without forcing. In our results we could identify three different local oscillatory modes: one in the Gulf of Finland with the two distinct periods 23 and 27 h, one in the Danish Belt Sea with a less distinct period in the range 23–27 h, and one in the Gulf of Riga with the period 17 h. The most pronounced mode is that in the Gulf of Finland. No clear indications of basin‐wide seiches in the Baltic could be found from our simulations. These results were further corroborated by a frequency analysis of sea level observations from the Baltic. This shows an amplification of the K1 and O1 tidal modes in the Gulf of Finland but not of the M2 and S2 modes. No such amplification was seen in the rest of the Baltic Sea. On the basis of our model simulations we propose that the sea level oscillations of the Baltic be regarded as an ensemble of weakly coupled local oscillations. Each oscillator corresponds to a “gulf mode” or “harbor mode” in a particular bay or subbasin. These are not proper eigenmodes since their energy gradually leaks out to the rest of the Baltic Sea, resulting in radiation damping. Nevertheless, their resonance may in fact be sharper than that of the proper basin‐wide eigenmodes.

The Gulf of Finland is an elongated estuary in the north-eastern Baltic Sea. It carries a heavy sea traffic that is a threat to this sensitive sea area. The annual amount of transported oil is presently over 100 Mtons and it is still expected to increase in the future. The Gulf of Finland is relatively small in size while its length is 400 km and the width varies between 48-135 km. In addition to the coastline shared between Finland, Russia and Estonia, the gulf has a large and fragmented archipelago where numerous small islands comprise about 6500 km of shores. Due to complex hydrography it has been seen necessary to apply a high resolution oil spill drift forecast system to the gulf. The OpHespo oil drift forecast system is an internet based tool for oil pollution response authorities around the Gulf of Finland. It is possible to calculate drift forecast up to two days ahead. The drift forecasts are based on four times per day updated wind and current forecasts. The wind forecasts originate from HIRLAM (HIgh Resolution Limited Area Model) run by the Finnish Meteorological Institute. The used HIRLAM model has a horizontal grid resolution of about 9 km that enables it to forecast some of the land-sea interactions having an effect to the wind speed and direction. The current forecasts are computed using a local area hydro-dynamic model. The local model is forced with the HIRLAM wind forecast, and hydro-dynamic boundary conditions at the entrance of the Gulf of Finland are obtained from the Hiromb operational Baltic Sea model. The OpHespo graphical user interface has been developed in close cooperation with the Finnish oil pollution response authorities that ensures a good functionality of the programme related to their tasks. Several workshops and training sessions have been arranged for oil pollution response authorities and meteorologists on duty during 2003-06. The challenge is that the end-users of OpHespo are aware of the added value that the programme gives to oil spill response exercises and planning of response measures. Training in advance contributes also to interpretation the forecast results in a reasonable way and raises up ideas of how to further develop the drift forecast system as specialist of different fields convene.

Polychlorinated diphenyl ethers, dibenzo-p-dioxins, dibenzofurans and biphenyls in seals and sediment from the gulf of finland

The nutrient load on the Gulf of Finland, the Baltic Sea, is estimated taking into account the export of nutrients from Lake Ladoga with Neva runoff, from the Chudsko-Pskovskoe Lake with Narva runoff, from a partial watershed of the Gulf of Finland, and wastewater discharges from St. Petersburg. The data used include the materials of state monitoring of water bodies and state statistical reports on northwestern Russia, materials of GUP Vodokanal Sankt Peterburga, the results of earlier researches of water quality formation in Lake Ladoga, the Gulf of Finland, and on their catchment, and the results of calculation of nutrient load on the gulf with the use of a model developed in the Institute of Limnology, RAS. Currently, the annual nutrient load on the Gulf of Finland is ∼5200 t Ptot and 70800 t Ntot. The phosphorus load exceeds the admissible levels recommended by the Helsinki Commission, thus suggesting the need to search for real ways to reduce the load in the future.