Wyniki wyszukiwania - Biblioteka Nauki

1

The natural and anthropogenic features of the coastal zone of the eastern Gulf of Finland

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Spiridonov M. A. , Zhamoida V. A.

Polish Geological Institute Special Papers

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2004

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tom Vol. 11

71-76

EN

The development of the coastal zone of the eastern Gulf of Finland has a long geological history and depends on the several main factors. The primary configuration of the shoreline is connected with tectonic movements, which even at present are displayed in slow uplifting of the northern coast and slow sinking of the southern one. However, the main features of the recent coastal zone were formed during degradation of the last glacial cover and essentially transformed during post-glacial period of different water bodies’ existence. The processes of the modern morpho- and litho-dynamic are very changeable and expressed in the different accumulative and erosion forms of relief. The anthropogenic activity during last centuries results in local reconstruction of the conditions of existence and development of the coastal zone.

2

Simplified Risk Analysis of Tanker Collisions in the Gulf of Finland

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Goerlandt F. , Hanninen M. , Stahlberg K. , Montewka J. , Kujala P.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2012

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tom Vol. 6, no. 3

381--387

EN

Maritime traffic poses various risks in terms of human casualties, environmental pollution or loss of property. In particular, tankers pose a high environmental risk as they carry very large amounts of oil or more modest amounts of possibly highly toxic chemicals. In this paper, a simplified risk assessment meth-odology for spills from tankers is proposed for the Gulf of Finland, for tankers involved in a ship-ship collision. The method is placed in a wider risk assessment methodology, inspired by the Formal Safety Assess-ment (FSA) and determines the risk as a combination of probability of occurrence and severity of the consequences. The collision probability model is based on a time-domain micro simulation of maritime traf-fic, for which the input is obtained through a detailed analysis of data from the Automatic Identification System (AIS). In addition, an accident causation model, coupled to the output of the traffic simulation model is proposed to evaluate the risk reduction effect of the risk control options. Further development of the model is needed, but the modular nature of the model allows for continuous improvement of the modules and the ex-tension of the model to include more hazards or consequences, such that the effect of risk control options can be studied and recommendations made. This paper shows some preliminary results of some risk analysis blocks for tanker collisions in the Gulf of Finland.

3

A Decision Support Tool for VTS Centers to Detect Grounding Candidates

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Mazaheri A. , Goerlandt F. , Kujala P. , Montewka J.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2012

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tom Vol. 6, no. 3

337--343

EN

AIS (Automatic Identification System) data analysis is used to define ship domain for ground-ing scenarios. The domain has been divided into two areas as inner and outer domains. Inner domain has clear border, which is based on ship dynamic characteristics. Violation of inner domain makes the grounding acci-dent unavoidable. Outer domain area is defined with AIS data analyzing. Outer domain shows the situation of own ship in compare with other similar ships that previously were in the same situation. The domain can be used as a decision support tool in VTS (Vessel Traffic Service) centers to detect grounding candidate vessels. In the case study presented in this paper, one type of ship, which is tanker, in a waterway to Sköldvik in the Gulf of Finland is taken into account.

4

A simple tool for the early prediction of the cyanobacteria Nodularia spumigena bloom biomass in the Gulf of Finland

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Lilover M.-J. , Laanemets J.

Oceanologia

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2006

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tom No. 48 (S)

213-229

EN

A fuzzy logic model for predicting the maximum biomass of the toxic cyanobacteria Nodularia spumigena bloom in the Gulf of Finland is suggested. The model bloom biomass depends on the phosphate conditions up to 15 June, including the excess phosphate left over after the spring bloom and on the phosphate inputs parameterised by wind mixing and upwelling from 1 May to 15 June. The surface layer temperature, set to vary from 14 to 23^(o)C, is regarded as a bloom regulating parameter. The model simulations showed that the predicted N. spumigena biomasses differ markedly from year to year and clearly depend on phosphate conditions up to 15 June.

5

Modelling nitrogen and phosphorus limitation on phytoplankton growth in Narva Bay, south-eastern Gulf of Finland

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Lessin G. , Lips I. , Raudsepp U.

Oceanologia

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2007

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tom No. 49 (2)

259-276

EN

The relative roles of nitrogen and phosphorus in the limitation of phytoplankton growth in Narva Bay, south-eastern Gulf of Finland, were studied by combining the results of numerical modelling and nutrient enrichment experiments. Modelled biomass-based intracellular nutrient concentrations (nutrient functions) were used to estimate the limiting nutrient in Narva Bay. Nutrient functions - NF ? [0; 1] for nitrogen and PF ? [0; 1] for phosphorus - define the dependence of the phytoplankton growth rate on nutrients: NF = PF = 1 corresponds to non-limitation of phytoplankton growth by nutrients, whereas NF = 0 or PF = 0 to zero growth. The biotests indicated the response of phytoplankton growth to an increase in nutrient concentration in the surrounding water. Three locations were selected for detailed analyses of temporal variations in the nutrient functions: the offshore station N12, station N8 at the mouth of the River Narva, and coastal station 38. The biotests were performed at the same stations. NF and PF reached values of 0.9 prior to the spring bloom. With the onset of the spring bloom, NF decreased rapidly and remained below 0.1 in the open part of Narva Bay for the rest of that period. In the coastal zone, NF was in excess of 0.1, with a local maximum in the river mouth area. PF decreased to 0.3-0.4 in the open bay after the spring bloom. In the coastal zone PF remained above 0.4, with a certain increase from the midsummer minimum towards the end of summer. The numerical modelling results clearly show that nitrogen limits phytoplankton growth in Narva Bay. Phosphorus limitation may occur only for a limited period and over a limited area at the Narva River mouth and other coastal locations. In general, the biotests backed up the modelling results, the main exception being in the open bay during summer. The model does not account for nitrogen fixation, however. Since N-fixing cyanobacteria were prevalent in the offshore area, the addition of phosphorus led to enhanced phytoplankton growth at station N12.

6

Water level forecasts for the eastern Gulf of Finland

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Klevanny K. A. , Gubareva V. P. , Mostamandy M. S. W. , Ozerova L. B.

Biuletyn Instytutu Morskiego w Gdańsku

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2001

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tom Vol. 28, No. 2

71--87

EN

The paper presents results of development and verification of the automated water level forecasting system for the eastern part of the Gulf of Finland with advance time 36 hours, which is based on two-dimensional hydrodynamic model of the Baltic Sea BSM3. The model is driven by the regional highresolution atmospheric model HIRLAM. Boundary conditions in the Danish Straits are received from a big scale model of the Baltic and North Seas (OPMODEL). The system works at the North-West Regional Administration of Hydro-Meteorological Service of Russia (NWHMS).

7

Estimating the Number of Tanker Collisions in the Gulf of Finland in 2015

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Hanninen P. , Kujala P. , Ylitalo J. , Kuronen J.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2012

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tom Vol. 6, no. 3

367--373

EN

The paper presents a model for estimating the number of ship-ship collisions for future traffic scenarios. The modeling is based on an approach where the number of collisions in an area is estimated as a product of the number collision candidates, i.e. the number of collisions of two ships, if no evasive maneuvers were made, and a causation probability describing the probability of making no evasive maneuvers. However, the number of collisions is presented as a combination of binomially distributed random variables. The model is applied for the assessment of tanker collision frequency in the Gulf of Finland in 2015. 2015 traffic is modeled as three alternative scenarios each having a certain probability of occurrence. The number of collisions can be presented either for each scenario, or as an estimate including the uncertainty in future marine traffic development by taking into account all scenarios and their occurrence probabilities.

8

Variability of currents over the southern slope of the Gulf of Finland

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Suhhova I. , Pavelson J. , Lagemaa P.

Oceanologia

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2015

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tom No. 57 (2)

132--143

EN

In our intraseasonal variability studies of currents in the coastal sea of the Gulf of Finland northeast of Pakri Peninsula, we compared the observation data from a bottom-mounted ADCP (March–June of 2009, 50 m depth) with the simulation data from High Resolution Operational Model of the Baltic (HIROMB). The structure of the current pattern appeared strongly dependent on the stratification conditions. The flow was quasi-barotropic during the periods of weak inverse thermal stratification at the end of winter season and at transition from the inverse thermal stratification to summer type stratification when the sea was thermally unstratified, but mostly two-layered (baroclinic) when the summer type thermal stratification had developed. The alternation of strong westward (eastward) currents (up to 30 cm s-1) in the upper layer is explained in terms of coastal upwelling (downwelling) due to favourable background winds. The measured and the modelled upper layers along isobath currents showed a noticeable correlation with the correlation coefficient of 0.52 and 0.82 during the periods of winter type and summer type stratifications, respectively, and the absence of a significant correlation during the transition period. The eastward (upwind) current episodes with speeds reaching 18 cm s-1 below the seasonal thermocline are likely to reflect the specific circulation response in the elongated basin caused by the easterly wind. The long-term mean (over 3.5 months) current vector (−2.0 cm s-1, −2.9 cm s-1) was westward in the upper sea and eastward, nearly along isobaths (1.1 cm s-1, −0.3 cm s-1) in the deeper layers.

9

Model estimates of microplastic potential contamination pattern of the eastern Gulf of Finland in 2018

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Martyanov S. D. , Isaev A. , Ryabchenko V. A.

Oceanologia

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2023

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tom Vol. 65 (1)

86--99

EN

The work is focused on the assessment of microplastics transport and distribution in the eastern part of the Gulf of Finland by means of numerical modeling. In the present study only the riverine sources of microplastics are taken into account. The presented model also accounts for possible sink of suspended microplastic particles into sediments due to simple parameterization of biogeochemical processes such as biofouling and ingestion by zooplankton. Two basic scenarios with different initial fall velocities of suspended microplastic particles, 0.2 m/day and 1.2 m/day, are discussed. The distribution of microplastics coming with the riverine waters of the Neva, Luga, and Narva rivers has been investigated, based on a numerical hydrodynamical hindcast of the year 2018. Model simulations show that the transport of suspended microplastics occurs along the northern coast of the considered area more intensively compared to the southern coast, especially in the easternmost shallow part of the gulf. The results are in a good agreement with other studies focused on the microplastic pollution of the Neva Bay, and with available observational data. The presented results and developed model can be useful tools aimed to assess the intensity and mechanisms of microplastic pollution of the eastern Gulf of Finland. The results can be used in the selection of areas for future environmental monitoring of microplastics pollution of the eastern part of the Gulf of Finland.

10

Impact of ship-borne nitrogen deposition on the Gulf of Finland ecosystem : an evaluation

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Raudsepp U. , Laanemets J. , Maljutenko I. , Hongisto M. , Jalkanen J. P.

Oceanologia

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2013

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tom No. 55 (4)

837--857

EN

The degree of inter-annual variability in spring and summer phytoplankton blooms and nitrogen fixation in response to the deposition of oxidized nitrogen originating from ship emissions (hereafter nitrogen deposition) was evaluated in the Gulf of Finland (Baltic Sea) based on 10-year (1997-2006) simulation results using a coupled hydrodynamic (GETM) and ecological (ERGOM) model. Ship emissions were generated for 2008 using the Ship Traffic Emission Assessment Model, and ship nitrogen deposition was calculated using the Hilatar chemistry-transport model over the Baltic Sea. The annual ship nitrogen deposition in the Gulf of Finland was 1.6 kt N, about 12% of the annual atmospheric deposition, and increased in summer, up to 30% compared to the monthly atmospheric deposition. Ship nitrogen deposition caused an increase in spring and post-bloom primary production in two functional groups (diatoms and flagellates), at the same time reducing phosphate resources in the upper layer. Nitrogen fixation due to ship nitrogen deposition decreased by 1-1.6 kt N year-1 (2-6%). The effect of ship nitrogen deposition on nitrogen fixation was greater in the western and central Gulf of Finland. The additional ship nitrogen deposition to the Gulf was practically compensated for by a decrease in nitrogen fixation.

11

Influence of landfast ice on the hydrography and circulation of the Baltic Sea coastal zone

100%

Merkouriadi I. , Leppäranta M.

Oceanologia

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2013

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tom No. 55 (1)

147-166

EN

The influence of landfast ice on hydrography and circulation is examined in Santala Bay, adjacent to the Hanko Peninsula, Gulf of Finland. Three-dimensional electromagnetic current meters and conductivity-temperature-depth (CTD) sensors were deployed in winters 1999-2000 and 2000-2001 during the Finnish-Japanese "Hanko 9012" experiment. In each winter, data collection started one month before the initial ice formation and lasted until one month after the ice had melted completely. Temperature and salinity are compared with long-term data from the Tvärminne Zoological Station, also located on the Hanko Peninsula. The water temperature was 2°C less than the long-term average. Ice formation and melting show up in the salinity evolution of the water body, which makes salinity a good indicator of ice formation and breakup in Santala Bay. The circulation under the ice became weaker by almost 1 cm s-1.

12

The Effects of Causation Probability on the Ship Collision Statistics in the Gulf of Finland

88%

Hanninen M. , Kujala P.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2010

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tom Vol. 4, no. 1

79--84

EN

In this study the marine traffic safety in the Gulf of Finland is studied by examining the collision probability estimates in a heavily used crossing area. In a commonly applied approach for estimating the probability of collision accidents, so-called number of collision candidates is multiplied with a so-called cau-sation probability. In this study a Bayesian network model for the causation probability estimation is applied with different parameter values in order to examine the effects of weather and human factors on collision probability in the crossing of Helsinki-Tallinn traffic and vessels navigating east- or westbound. The results show that the probability of collisions is very sensitive to the causation probability value and it should be modelled with great care to obtain reliable results.

13

Functional response of midsummer planktonic and benthic communities in the Neva Estuary (eastern Gulf of Finland) to anthropogenic stress

88%

Golubkov S. M. , Alimov A. F. , Telesh I. V. , Anokhina L. E. , Maximov A. A. , Nikulina V. N. , Pavel'eva E. B. , Panov V. E.

Oceanologia

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2003

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tom No. 45 (1)

53-66

EN

Long-term hydrobiological research has shown that the functioning of the ecosystem of the Neva Estuary, one of the largest Baltic estuaries, has changed greatly since the beginning of the 20th century. Ineffective local water management in St. Petersburg during the last twenty years has stimulated the development of a natural "biological plug" in the salt barrier zone in the inner part of the estuary and has altered the ecosystem's functioning. These changes include an increase in primary production, in the primary production:organic matter decomposition ratio, and in pelagic-benthic coupling. It has also given rise to filamentous algae blooms and intensive secondary pollution in the coastal zone of the Neva Estuary. The primary production of phytoplankton in the inner part of the estuary has reached 2.3 gC m-2, that of the filamentous algae Cladophora glomerata 5.5 gC m-2 these figures are much higher than in other regions of the Gulf of Finland.

14

Effects of environmental variables on midsummer dinoflagellate community in the Neva Estuary (Baltic Sea)

88%

Golubkov M. , Nikulina V. , Golubkov S.

Oceanologia

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2019

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tom No. 61 (2)

197--207

EN

Dinoflagellates account for most of the harmful phytoplankton species but relatively little is known about the specific responses of different species to environmental variables. 21 dino-flagellate species were recorded in the plankton of the Neva Estuary since the mid-19th century. 14- year long data of midsummer dinoflagellate biomass was statistically analyzed in the Neva Estuary to show the changes in dinoflagellate species in relation to environmental factors. Biomasses of Dinophysis norvegica (Clapared & Lachmann 1859), Prorocentrum lima ((Ehrenberg) F.Stein 1878) and Peridinium aciculiferum (Lemmermann 1900) had very similar positive relationships with salinity, temperature, phosphorus and suspended particulate organic matter concentrations while the biomass of the other common species Peridinium cinctum ((Müller) Ehrenberg 1832) and Peridinium sp. mostly showed quite opposite trends. Climate fluctuations leading to changes in the environmental variables could significantly affect the composition and productivity of the dinoflagellate community. Biomass of Glenodinium sp. and Peridinium sp. positively correlated with primary production and biomass and chlorophyll a concentration, but did not show a positive relationship with phosphorus. This may be due to the fact that these species in the conditions of the Neva Estuary, apparently, are more consumers than producers of organic matter, feeding on algae and cyanobacteria of phytoplankton. Therefore, to interpret the relationships between the dinoflagellate biomass and environmental variables one should take into account that the species of this group is characterized by mixotrophy and, consequently, their biomass may depend not only on the conditions of autotrophic, but also heterotrophic nutrition.

15

Large halocline variations in the Northern Baltic Proper and associated meso- and basin-scale processes

88%

Elken J. , Mälkki P. , Alenius P. , Stipa T.

Oceanologia

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2006

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tom No. 48 (S)

91-117

EN

The Northern Baltic Proper is a splitting area of the Baltic Sea saline water route towards the two terminal basins - the Gulf of Finland and the Western Gotland Basin. Large halocline variations (vertical isopycnal displacements of more than 20 m, intra-halocline current speeds above 20 cm s-1 appear during and following SW wind events, which rapidly increase the water storage in the Gulf of Finland and reverse the standard estuarine transport, causing an outflow in the lower layers. In the channel of variable topography, basin-scale barotropic flow pulses are converted into baroclinic mesoscale motions such as jet currents, sub-surface eddies and low-frequency waves. The associated dynamics is analysed by the results from a special mesoscale experiment, routine observations and numerical modelling.

16

Attributing mean circulation patterns to physical phenomena in the Gulf of Finland

88%

Westerlund A. , Tuomi L. , Alenius P. , Miettunen E. , Vankevich R. E.

Oceanologia

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2018

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tom No. 60 (1)

16--31

EN

We studied circulation patterns in the Gulf of Finland, an estuary-like sub-basin of the Baltic Sea. According to previous observations and model results, the long-term mean circulation in the gulf is cyclonic and mainly density driven, whereas short-term circulation patterns are wind driven. We used the high-resolution 3D hydrodynamic model NEMO to simulate the years 2012-2014. Our aim was to investigate the role of some key features, like river runoff and occasional events, in the formation of the circulation patterns. Our results show that many of the differences visible in the annual mean circulation patterns from one year to another are caused by a relatively small number of high current speed events. These events seem to be upwelling-related coastal jets. Although the Gulf of Finland receives large amounts of fresh water in river runoffs, the inter-annual variations in runoff did not explain the variations in the mean circulation patterns.

17

Regional algorithms for the estimation of chlorophyll and suspended matter concentration in the Gulf of Finland from MODIS-Aqua satellite data

88%

Vazyulya S. , Khrapko A. , Kopelevich O. , Burenkov V. , Eremina T. , Isaev A.

Oceanologia

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2014

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tom No. 56 (4)

737--756

EN

Validation of algorithms for the retrieval of concentrations of chlorophyll (Chl) and total suspended matter (TSM) in the Gulf of Finland from satellite ocean colour data was carried out using field measurement data from summer 2012 and 2013. These data included spectral values of the remote sensing reflectance Rrs(λ), Chl and TSM concentrations. Testing of the existing algorithms (OC4v4, OC3M, and the Baltic regional algorithms developed by Polish specialists) showed that all of them overestimated Chl several times. The new regional algorithms were developed on the basis of measured values of Rrs(λ), Chl and TSM (40 stations in total). Direct comparison of Chl and TSM values, obtained from MODIS-Aqua data with the algorithms developed here, with their in situ values showed reasonable agreement. The spatial distributions of Chl and TSM concentrations were constructed from MODIS-Aqua data. Errors of the atmospheric correction were analysed.

18

Case-Study Modelling Analysis of Hydrodynamics in the Nearshore of the Baltic Sea Forced by Extreme Along-shore Wind in the Case of a Cross-shore Obstacle

75%

Sokolov A. , Chubarenko B.

Archives of Hydro-Engineering and Environmental Mechanics

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2018

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tom Vol. 65, nr 3

163--176

EN

In the current study we use a three-dimensional model with hydrodynamic and spectral wave modules operating in a coupled mode to simulate the response of currents and wind wave fields to winds of 20–25 m/sec offshore of the protective structure of the Saint Petersburg Flood Prevention Facility Complex. The model was calibrated against field data, which allowed us to obtain a tool describing storm situations in the eastern part of the Gulf of Finland with a satisfactory accuracy. The numerical modeling showed that the protective dam did not have a noticeable effect on the levels of stormsurge, significantwave height, or current speed in areas seaward of the dam. The increase in erosion processes on the southern shore of the easternmost part of the Gulf of Finland in recent past has most probably been related to other factors. We found that if a west or south-west wind of at least 25 m/s blows over the Baltic Sea for at least 16 hours, the level of storm surges seaward of the dam may reach 3 or more meters. An artificial strengthening of the coastline and the creation of shore protection structures are recommended.

19

Life in sympatry : coexistence of native Eurytemora affinis and invasive Eurytemora carolleeae in the Gulf of Finland (Baltic Sea)

75%

Sukhikh N. , Souissi A. , Souissi S. , Holl A.-C. , Schizas N. V. , Alekseev V.

Oceanologia

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2019

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tom No. 61 (2)

227--238

EN

The invasion of exotic species into native ecosystems is becoming a crucial issue in global biology. Over the last ten years, at least 45 invasions of aquatic species have been reported in the eastern part of the Gulf of Finland; the majority of them were introduced through ballast water. Recently, invasion of the estuarine calanoid copepod Eurytemora carolleeae (Temoridae), originating from North America, has been reported in several European estuaries and particularly in the Gulf of Finland. This species is morphologically very similar to the native Eurytemora affinis, but it is easily discriminated by molecular markers. In this study, we monitored the distribution area of the invasive copepod species in European waters, as well as the population structure of (native) E. affinis and (invasive) E. carolleeae, from 2006 to 2018 in the Gulf of Finland. The population density of E. affinis was significantly higher, compared to E. carolleeae, during most of the study period. The only exception was Neva Bay in 2010, wherein the invasive species dominated possibly due to high temperatures and differences in the levels of fish predation. The reproductive performance of E. carolleeae was also higher than that of E. affinis. These results show different population dynamics between the two species. It was revealed that invasive E. carolleeae develops in some of the very same habitats as native E. affinis, thereby potentially becoming a significant component of the zooplankton in the studied area. Moreover, invader has the potential to displace native E. affinis.

20

Integrated Assessment of Groundwater Pollution from the Landfill of Sewage Sludge

75%

Dregulo A. M. , Bobylev N. G.

Journal of Ecological Engineering

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2021

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tom Vol. 22, nr 1

68--75

EN

The purpose of this study was to assess the groundwater contamination from a sewage sludge landfill. The analysis was carried out in 2017 in accordance with the requirements of the national legislation for monitoring landfills and priority pollutants. The samples of groundwater from the landfill were taken from 25 observation wells, from depths of 45–60 m. The status and dynamics of changes in the landfill groundwater quality were estimated according to the data from the groundwater observation wells of the city observation network with regard to the chemical composition of groundwater and national standards of groundwater quality. The forecast estimates of a low level of pollutants entering groundwater through the soils characterized by low filtration properties were not justified. The concentration of heavy metals in groundwater was within the following range: Fe > Mn > Zn > Al > Cu > Ni > Pb > Cd > Hg. The excess concentration of the nitrogen-containing pollutants was observed within the range from 1.5 to 76 (on average 10 times) above the background value. The organic contamination of landfill groundwater (COD) is 2–9 times and BOD5 – 1.5–3 times higher than the average background value of groundwater observation wells in the city network. The probable cause for the pollutants entry into groundwater is associated with lithogenous and exogenous fracturing of the rocks and insufficient efficiency of the existing anti-filtration system of the landfill.