scholarly journals Natural and human control of the coastal development. Baltic sea, Lithuania

Author(s):  
Darius Jarmalavičius ◽  
Gintautas Žilinskas ◽  
Donatas Pupienis ◽  
Viktoras Karaliūnas ◽  
Rasa Janušaitė

Sea coast - a geomorphic system that maintains its stability through the exchange of sand between its individual elements. As environmental conditions change, the shore system changes by adapting to maintain its stability. Natural processes such as sea level fluctuation and extreme storms cause continuous shoreline change. Feedback effects create natural elements inhibiting external factors altering shore stability. There is a relative equilibrium between natural factors and the shore and in the absence of sudden changes the shore system retains its quasi-stability over a long period of time. This is reflected in the development of the Baltic Sea coast at Lithuania in the 20th century. During this period, of naturally developing coastline did not experience drastic changes. Both the position of the shoreline and the change in the volume of sand on shore did not undergo catastrophic changes. Everything changes radically when a human intervenes in natural processes by starting to develop economic activities on the shore. Especially significant changes occur during the construction or reconstruction of hydro-technical structures. In the case of Lithuania, the hydro-technical structures that caused the biggest changes were the jetties of Klaipeda and Šventoji ports and the pier of Palanga. Since the shore sand transfer resultant at the Lithuanian nearshore is directed from south to north, the resulting barrier cats this drift, disrupting the free circulation of sand along the shore and forcing sand to accumulate on the southern side of the jetty. Meanwhile, on the north side of the jetty, when the sand supply is lost, the coast begins to retreat. These changes are exacerbated by the deepening of the Klaipeda port cana

2003 ◽  
pp. 136-146
Author(s):  
K. Liuhto

Statistical data on reserves, production and exports of Russian oil are provided in the article. The author pays special attention to the expansion of opportunities of sea oil transportation by construction of new oil terminals in the North-West of the country and first of all the largest terminal in Murmansk. In his opinion, one of the main problems in this sphere is prevention of ecological accidents in the process of oil transportation through the Baltic sea ports.


Author(s):  
Angelina E. Shatalova ◽  
Uriy A. Kublitsky ◽  
Dmitry A. Subetto ◽  
Anna V. Ludikova ◽  
Alar Rosentau ◽  
...  

The study of paleogeography of lakes is an actual and important direction in modern science. As part of the study of lakes in the North-West of the Karelian Isthmus, this analysis will establish the dynamics of salinity of objects, which will allow to reconstruct changes in the level of the Baltic Sea in the Holocene.


2021 ◽  
Vol 8 ◽  
Author(s):  
Vilnis Frishfelds ◽  
Juris Sennikovs ◽  
Uldis Bethers ◽  
Jens Murawski ◽  
Andrejs Timuhins

This study investigates a water transport features by extending Copernicus Marine Environment Service (CMEMS) to the Liepaja coast-port-channel-lake system with a two-way nested model. The Liepaja lake and Liepaja port are connected by Trade channel. The Liepaja port has three gates—the openings in wave breakers connecting the port aquatory with the Baltic sea. Each of gates has a corresponding dredged channel for securing the navigation. A hydrodynamic model is set up to study the flow and water level in this system. The area of the port gates, port and Trade channel are resolved by 33 m grid. The model results are verified against currents and sea level observations inside/outside port, Trade channel and Liepaja lake. Results and observations show that strong currents occur in the Trade channel in case of rapid sea level change in Baltic sea despite the Trade channel is rather shallow at the connection with Liepaja lake. The northern part of the Liepaja lake gets filled with brackish water during storm surge events. The channel has notable alternating current also during a relatively calm weather due to the port seiches. Long and narrow shape of the channel implies the Helmholtz type oscillations between the lake and the port with a period in approximately semidiurnal range. Hydrodynamic simulations describe well these oscillations but the phase of hourly scale oscillations in the port may differ in case of weak external forcing. Water exchange is significantly increased by the transit (gate to gate) sea currents. This transit flow usually occurs between South or Central gate and the North gate carrying sea water into the port. Northward flow of the surface layer is more characteristic in the port aquatory due the prevailing south-western winds. There are intense morphological processes at the coastline and underwater slope near the Liepaja port due to a sandy western coastline of Latvia, long fetch of the waves and strong currents at the port gates. Liepaja port is one of the Latvian ports in HywasPort operational service of hydrodynamics, waves and siltation.


2013 ◽  
Vol 10 (4) ◽  
pp. 2725-2735 ◽  
Author(s):  
M. Blumenberg ◽  
C. Berndmeyer ◽  
M. Moros ◽  
M. Muschalla ◽  
O. Schmale ◽  
...  

Abstract. 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.


2011 ◽  
Vol 8 (11) ◽  
pp. 3219-3230 ◽  
Author(s):  
K. Kuliński ◽  
J. Pempkowiak

Abstract. This paper presents the results of a comprehensive study of the Baltic Sea carbon budget. The Baltic Sea is very much influenced by terrestrial carbon input. Rivers are the largest carbon source, and their input amounts to 10.90 Tg C yr−1 (Tg = 1012 g) with a 37.5% contribution of organic carbon. On the other hand, carbon is effectively exported from the Baltic to the North Sea (7.67 Tg C yr−1) and is also buried in bottom sediments (2.73 Tg C yr−1). The other sources and sinks of carbon are of minor importance. The net CO2 emission (1.05 Tg C yr−1) from the Baltic to the atmosphere was calculated as the closing term of the carbon budget presented here. There is a net loss of organic carbon, which indicates that the Baltic Sea is heterotrophic.


2014 ◽  
Vol 14 (15) ◽  
pp. 21943-21974 ◽  
Author(s):  
J. E. Jonson ◽  
J. P. Jalkanen ◽  
L. Johansson ◽  
M. Gauss ◽  
H. A. C. Denier van der Gon

Abstract. Land-based emissions of air pollutants in Europe have steadily decreased over the past two decades, and this decrease is expected to continue. Within the same time span emissions from shipping have increased, although recently sulphur emissions, and subsequently particle emissions, have decreased in EU ports and in the Baltic Sea and the North Sea, defined as SECAs (Sulphur Emission Control Areas). The maximum allowed sulphur content in marine fuels in EU ports is now 0.1%, as required by the European Union sulphur directive. In the SECAs the maximum fuel content of sulphur is currently 1% (the global average is about 2.4%). This will be reduced to 0.1% from 2015, following the new IMO rules (International Maritime Organisation). In order to assess the effects of ship emissions in and around the Baltic Sea and the North Sea, regional model calculations with the EMEP air pollution model have been made on a 1/4° longitude × 1/8° latitude resolution, using ship emissions in the Baltic Sea and the North Sea that are based on accurate ship positioning data. The effects on depositions and air pollution and the resulting number of years of life lost (YOLL) have been calculated by comparing model calculations with and without ship emissions in the two sea areas. The calculations have been made with emissions representative of 2009 and 2011, i.e. before and after the implementation of stricter controls on sulphur emissions from mid 2010. The calculations with present emissions show that per person, an additional 0.1–0.2 years of life lost is estimated in areas close to the major ship tracks with present emission levels. Comparisons of model calculations with emissions before and after the implementation of stricter emission control on sulphur show a general decrease in calculated particle concentration. At the same time, however, an increase in ship activity has resulted in higher emissions and subsequently air concentrations, in particular of NOx, especially in and around several major ports. Additional model calculations have been made with land based and ship emissions representative of year 2030. Following a decrease in emissions, air quality is expected to improve, and depositions to be reduced. Particles from shipping are expected to decrease as a result of emission controls in the SECAs. Further controls of NOx emissions from shipping are not decided, and calculations are presented with and without such controls.


2013 ◽  
Vol 58 (1) ◽  
pp. 26-36
Author(s):  
Mait Lang ◽  
Agris Traškovs ◽  
Linda Gulbe

Abstract The space-borne Moderate Resolution Imaging Spectroradiometer (MODIS) data based net primary production (NPP) product from Numerical Terradynamic Simulation Group (NTSG) was tested in the Kurzeme region, Latvia using a stand-wise forest inventory database. The NPP product has been validated globally and found to have no overall bias. In this study the NPP product was compared with stem biomass increment and soil fertility in respect to distance from the Baltic Sea coast. For each MODIS NPP product pixel we calculated forest cover, share of coniferous trees, average stem biomass increment and average site fertility (growth potential estimate). Then, 2432 pixels with a forest cover over 75% were selected for analysis. The results indicated that MODIS NPP decreased with distance from Baltic Sea coast but stem biomass increment and site fertility indicated a trend of increase. There was no functional relationship between MODIS NPP and stem biomass increment. Analysis of the landcover map used by NTSG for MODIS NPP product showed that the classes “Evergreen needleleaf” and “Mixed forests” differentiated only 10% by mode value of coniferous proportions in species composition. A non-natural jump was detected in the MODIS NPP values at a longitude of 22.5 degrees east corresponding to the border of the coarse scale meteorological dataset (NCEP Reanalysis (R2)) data representation unit. According to the results the MODIS NPP product is not applicable for regional level planning but can probably provide only rough average estimates of NPP for the Baltic region


Author(s):  
Jan Harff ◽  
Wolfram Lemke ◽  
Reinhard Lampe ◽  
Friedrich Lüth ◽  
Harald Lübke ◽  
...  

Phytotaxa ◽  
2021 ◽  
Vol 484 (1) ◽  
pp. 121-128
Author(s):  
ADIL Y. AL-HANDAL ◽  
ANGELA WULFF ◽  
CHIARA PENNESI

Described is here Mastogloia jahniae sp. nov. a species new to science from Skatan on the Baltic Sea, east coast of Sweden. Description of this new species is based on light and scanning electron microscopy. The new species is classified in the Mastogloia section Ellipticae and is characterized by having radiating short and long striae around the central area, sinuous raphe branches and partecta displaced toward the middle of the valve by a siliceous flange. M. jahniae sp. nov. in terms of size is rather small whereas in terms of ecology appears an epipelic brackish water species. The new species was rather rare in all samples collected from Skatan and has not been found in the other adjacent regions sampled. A comparison with similar established Mastogloia species is provided.


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