Oceanologia No. 59 (1) / 17


Contents


Original research article


Short communications


Original research article



Tracking trends in eutrophication based on pigments in recent coastal sediments
Oceanologia 2017, 59(1), 1-17
http://dx.doi.org/10.1016/j.oceano.2016.08.003

Małgorzata Szymczak-Żyła1, Magdalena Krajewska1, Aleksandra Winogradow1, Agata Zaborska1, Gijs D. Breedveld2, Grażyna Kowalewska1,*
1Institute of Oceanology of the Polish Academy of Sciences, Sopot, Poland;
e-mail: Kowalewska@iopan.gda.pl
*corresponding author
2Norwegian Geotechnical Institute, Oslo, Norway

keywords: Eutrophication; Pigments; Markers; Sediments; Baltic Sea; Norwegian fjords

Received 15 June 2016, Accepted 22 August 2016, Available online 29 September 2016

Abstract

Eutrophication in two different coastal areas – the Gulf of Gdańsk (southern Baltic) and the Oslofjord/Drammensfjord (Norway) – both subject to human pressure and with restricted water exchange with adjacent seas, was investigated and compared. Sediment cores (up to 20 cm long) were collected at 12 stations using a core sampler, 6 in each of the two areas, and divided into sub-samples. The physicochemical parameters characterizing the adjacent water column and near-bottom water, i.e. salinity, oxygen concentration and temperature, were measured during sample collection. Chlorophylls-a, -b and -c, their derivatives and selected carotenoids were determined for all the samples, as were additional parameters characterizing the sediments, i.e. Corg, Ntot, δ13C and δ15N, grain size. 210Pb activity was also determined and on that basis sediment mixing and accumulation rates were estimated. The distribution of pigments in sediments was related to environmental conditions, the sampling site location and sediment characteristics. The results are in agreement with other observations that eutrophication in the Gulf of Gdańsk has increased, especially since the 1970s, whereas in the Oslofjord it decreased during the same period. The pigments are better preserved in inner Oslofjord sediments than in those from the Gulf of Gdańsk. The results demonstrate that the sum of chloropigments-a in sediments calculated per dry weight of sediments is a valuable measure of eutrophication, providing that the monitoring site is selected properly, i.e. sediments are hypoxic/anoxic and non-mixed. Besides, the results confirm previous observations that the percentages of particular chlorophyll-a derivatives in the sum of chloropigments-a are universal markers of environmental conditions in a basin. The ratios of chloropigments-b and chlorophylls-c to the sum of chloropigments-a (ΣChlns-b/ΣChlns-a; Chls-c/ΣChlns-a) may by applied as complementary markers of freshwater and marine organic matter input, respectively.
full, complete article - PDF (2347 K)


Application of Dean's curve to investigation of a long-term evolution of the southern Baltic multi-bar shore profile
Oceanologia 2017, 59(1), 18-27
http://dx.doi.org/10.1016/j.oceano.2016.06.001

Grzegorz R. Cerkowniak*, Rafał Ostrowski, Zbigniew Pruszak
Institute of Hydro-Engineering, Polish Academy of Sciences (IBW PAN), Gdańsk, Poland;
e-mail: g.cerkowniak@ibwpan.gda.pl

keywords: Cross-shore profile; Bars; Shoreline position; Dean's curve; Nearshore sediment resources

Received 29 February 2016, Accepted 10 June 2016, Available online 24 June 2016

Abstract

The paper presents the results of studies on the long-term evolution of the multi-bar cross-shore profiles. The analysis is focused on time-dependent variability of shoreline position, a modified parameter A of the conventional Dean's equation and a parameter F describing the amount of nearshore sediment resources in the multi-bar cross-shore profile. The study also deals with interrelationships between these quantities. The analysis is carried out using field data collected at Lubiatowo, Poland, on the dissipative shore, representative for the south Baltic. The considered coastal segment is found to be stable in the long-term scale. The results of analysis show that the parameter A can either increase or decrease together with the shoreline advance. It is concluded that the shoreline position change is a parameter unsatisfactorily representative for behaviour of the seashore. The use of the Dean's approximation for estimation of the sediment resources F on the multi-bar seashore profiles is found reasonable to eliminate the effects of peculiarities of such shores.
full, complete article - PDF (1196 K)


The impact of tides and waves on near-surface suspended sediment concentrations in the English Channel
Oceanologia 2017, 59(1), 28-36
http://dx.doi.org/10.1016/j.oceano.2016.06.002

Nicolas Guillou1,*, Aurélie Rivier1,2, Georges Chapalain1, Francis Gohin2
1Laboratoire de Génie Côtier et Environnement (LGCE), Cerema/DTecEMF/DS, Plouzané, France;
e-mail: nicolas.guillou@cerema.fr
2ODE-DYNECO-PELAGOS, Ifremer, Centre de Bretagne, Technople Brest-Iroise, Plouzané, France
*corresponding author

keywords: Sediment transport; Numerical modeling; Satellite; ROMS; MERIS; MODIS

Received 5 April 2016, Accepted 23 June 2016, Available online 9 July 2016

Abstract

Numerous ecological problems of continental shelf ecosystems require a refined knowledge of the evolution of suspended sediment concentrations (SSC). The present investigation focuses on the spatial and temporal variabilities of near-surface SSC in coastal waters of the English Channel (western Europe) by exploiting numerical predictions from the Regional Ocean Modeling System ROMS. Extending previous investigations of ROMS performances in the Channel, this analysis refines, with increased spatial and temporal resolutions, the characterization of near-surface SSC patterns revealing areas where concentrations are highly correlated with evolutions of tides and waves. Significant tidal modulations of near-surface concentrations are thus found in the eastern English Channel and the French Dover Strait while a pronounced influence of waves is exhibited in the Channel Islands Gulf. Coastal waters present furthermore strong SSC temporal variations, particularly noticeable during storm events of autumn and winter, with maximum near-surface concentrations exceeding 40 mg l−1 and increase by a factor from 10 to 18 in comparison with time-averaged concentrations. This temporal variability strongly depends on the granulometric distribution of suspended sediments characterized by local bi-modal contributions of silts and sands off coastal irregularities of the Isle of Wight, the Cotentin Peninsula and the southern Dover Strait.
full, complete article - PDF (9124 K)


Characteristics and inter-annual changes in temperature, salinity and density distribution in the Gulf of Riga
Oceanologia 2017, 59(1),37-48
http://dx.doi.org/10.1016/j.oceano.2016.07.001

Maris Skudra1,2,*, Urmas Lips1
1Marine Systems Institute, Tallinn University of Technology, Tallinn, Estonia;
*corresponding author
e-mail: maris.skudra@msi.ttu.ee
2Latvian Institute of Aquatic Ecology, Riga, Latvia

keywords: Gulf of Riga; Temperature; Salinity; Vertical stratification; Internal Rossby radius

Received 12 January 2016, Accepted 4 July 2016, Available online 16 July 2016

Abstract

Available CTD profiles from the Gulf of Riga (May–August, 1993–2012) were analyzed to study inter-annual and long-term changes in temperature, salinity and density in relation to river runoff and atmospheric forcing (e.g. Baltic Sea Index). To describe temporal changes in vertical stratification, the upper mixed layer (UML) and deep layer (DL) parameters were estimated. On average the UML depth increases from 8.7 m in May to 9.0, 11.5 and 13.7 m in June, July and August, respectively, and the UML temperature increases from 8.0°C to 12.5, 18.7 and 18.6°C (May, June, July and August) while the UML salinity increases from 4.90 g kg−1 to 5.14, 5.28 and 5.38 g kg−1, respectively. High correlation (r = −0.82) was found between the inter-annual changes in river runoff (spring) and mean salinity in the UML in August as well as between DL mean salinity (r = 0.88) and density (r = 0.84) in the Irbe Strait and DL mean salinity and density in the Gulf of Riga. Inter-annual changes in the UML depth as well as in DL salinity and density had a significant correlation with the changes in Baltic Sea Index. The strongest stratification (August) can be observed in the years with the highest UML temperature and the highest river run-off in spring. We suggest that the predicted increase in water temperature and changes in river run-off due to the climate change would result in faster development of the seasonal thermocline in spring and stronger vertical stratification in summer.
full, complete article - PDF (2271 K)


Effect of physicochemical parameters on zooplankton in the brackish, coastal Vistula Lagoon
Oceanologia 2017, 59(1), 49-56
http://dx.doi.org/10.1016/j.oceano.2016.08.001

Ewa Paturej, Agnieszka Gutkowska, Jacek Koszałka*, Magdalena Bowszys
Department of Tourism, Recreation and Ecology, University of Warmia and Mazury, Olsztyn, Poland;
e-mail: jacko@uwm.edu.pl
*corresponding author

keywords: Physicochemical properties; Zooplankton; Brackish waters; Coastal lagoon

Received 11 August 2015, Accepted 8 August 2016, Available online 21 August 2016

Abstract

This paper analyzes whether physicochemical properties significantly influence the occurrence of zooplankton in a brackish reservoir. The studies were carried out on the Vistula Lagoon in August and September from 2006 to 2009 at 32 research sites. The environmental conditions in the Vistula Lagoon varied widely. At the time of the investigation, 17 species of rotifers, six species of Cladocera, and ten species of Copepoda were noted, and the total density of plankton fauna ranged from 145 to 765 ind. dm−3. Statistical analysis demonstrated a significant correlation between the occurrence of some zooplankton species and certain environmental parameters, whereas the sampling sites were grouped according to study years. The zooplankton systems recorded at the research sites in 2006 constitute the most disparate group. Thus, it can be concluded that physicochemical properties might significantly impact both individual species (depending on their environmental demands) and entire zooplankton clusters.
full, complete article - PDF (823 K)


Testing the performance of empirical remote sensing algorithms in the Baltic Sea waters with modelled and in situ reflectance data
Oceanologia 2017, 59(1), 57-68
http://dx.doi.org/10.1016/j.oceano.2016.08.002

Martin Ligi1,*, Tiit Kutser2,*, Kari Kallio3,*, Jenni Attila3, Sampsa Koponen3, Birgot Paavel2, Tuuli Soomets2, Anu Reinart1,*
1Tartu Observatory, Nõo Parish, Tartu County, Estonia;
e-mail: ligi@to.ee, tiit.kutser@sea.ee, kari.y.kallio@ymparisto.fi, Anu.Reinart@to.ee
*corresponding author
2Estonian Marine Institute, University of Tartu, Tallinn, Estonia
3Finnish Environment Institute, Helsinki, Finland

keywords: Band-ratio algorithm; Marine optics; Baltic Sea

Received 4 April 2016, Accepted 8 August 2016, Available online 24 August 2016

Abstract

Remote sensing studies published up to now show that the performance of empirical (band-ratio type) algorithms in different parts of the Baltic Sea is highly variable. Best performing algorithms are different in the different regions of the Baltic Sea. Moreover, there is indication that the algorithms have to be seasonal as the optical properties of phytoplankton assemblages dominating in spring and summer are different. We modelled 15,600 reflectance spectra using HydroLight radiative transfer model to test 58 previously published empirical algorithms. 7200 of the spectra were modelled using specific inherent optical properties (SIOPs) of the open parts of the Baltic Sea in summer and 8400 with SIOPs of spring season. Concentration range of chlorophyll-a, coloured dissolved organic matter (CDOM) and suspended matter used in the model simulations were based on the actually measured values available in literature. For each optically active constituent we added one concentration below actually measured minimum and one concentration above the actually measured maximum value in order to test the performance of the algorithms in wider range. 77 in situ reflectance spectra from rocky (Sweden) and sandy (Estonia, Latvia) coastal areas were used to evaluate the performance of the algorithms also in coastal waters. Seasonal differences in the algorithm performance were confirmed but we found also algorithms that can be used in both spring and summer conditions. The algorithms that use bands available on OLCI, launched in February 2016, are highlighted as this sensor will be available for Baltic Sea monitoring for coming decades.
full, complete article - PDF (2023 K)


Processes and factors influencing the through-flow of new deepwater in the Bornholm Basin
Oceanologia 2017, 59(1), 69-80
http://dx.doi.org/10.1016/j.oceano.2016.09.001

Anders Stigebrandt
Department of Marine Sciences, University of Gothenburg, Gothenburg, Sweden;
e-mail: anders.stigebrandt@marine.gu.se


keywords: Vertical mixing; Inflow of new deepwater; Salinity; Currents; Baltic Sea

Received 3 June 2016, Accepted 11 September 2016, Available online 23 September 2016

Abstract

This paper is based on the idea that the hydrographical conditions in the Bornholm Basin, and any other basin, can be understood from knowledge of general hydromechanical principles and basin-specific factors. Published results on the variability of the vertical stratification are shown and discussed. Such analyses demonstrate the residence time of water at different depth levels. Different modes of currents forced by winds and by stratification gradients at open vertical boundaries are presented. Vertical mixing is discussed and published results for the Bornholm Basin are shown. An experiment demonstrates that the diffusive properties of the enclosed basin, i.e. below the sill depth of the Słupsk Furrow, can be computed quite well from the horizontal mean vertical diffusivity obtained from historical hydrographical observations. A published two decades long simulation of the vertical stratification shows that the through flow and modification of new deepwater in the Bornholm Basin can be well described based on existing knowledge regarding crucial hydromechanical processes. It also suggests, indirectly, that there should be a weak anticyclonic circulation above the sill depth, which is supported by current measurements.
full, complete article - PDF (3231 K)

Short communications



New data on benthic Naididae (Annelida, Clitellata) in Polish brackish waters
Oceanologia 2017, 59(1), 81-84
http://dx.doi.org/10.1016/j.oceano.2016.06.003

Lena Marszewska1,*, Elżbieta Dumnicka2, , Monika Normant-Saremba1
1Institute of Oceanography, University of Gdańsk, Gdynia, Poland;
e-mail: lena.marszewska@ug.edu.pl
*corresponding author
2Institute of Nature Conservation, Polish Academy of Sciences, Kraków, Poland

keywords: Oligochaeta; Tubificidae; Soft bottom infauna; Port of Gdynia; Gulf of Gdańsk; Baltic Sea

Received 26 February 2016, Accepted 23 June 2016, Available online 22 July 2016

Abstract

This paper presents new findings on oligochaete species inhabiting Polish brackish waters. Identification of 455 specimens collected in September 2013 and July 2014 during the macrozoobenthos survey in the Port of Gdynia (the Gulf of Gdańsk, the southern Baltic Sea, Poland) showed the presence of six species belonging to two subfamilies Naidinae and Tubificinae.
full, complete article - PDF (466 K)


The killer shrimp Dikerogammarus villosus (Crustacea, Amphipoda) invades Lithuanian waters, South-Eastern Baltic Sea
Oceanologia 2017, 59(1), 85-91
http://dx.doi.org/10.1016/j.oceano.2016.08.004

Eglė Šidagytė1,*, Sabina Solovjova2,*, Viktė Šniaukštaitė1,*, Andrius Šiaulys2,*, Sergej Olenin2,*, Kęstutis Arbačiauskas1,*
1Nature Research Centre, Vilnius, Lithuania;
e-mail: e.sidagyte@gmail.com, sabina.lt@gmail.com, vikte.sn@gmail.com, andrius.siaulys@jmtc.ku.lt, sergej.olenin@jmtc.ku.lt, arbas@ekoi.lt
*corresponding author
2Marine Science and Technology Centre, Klaipėda, Lithuania

keywords: Alien species; Ponto-Caspian invaders; First records; Invasive crustaceans in Lithuania

Received 5 August 2016, Accepted 29 August 2016, Available online 9 September 2016

Abstract

The killer shrimp Dikerogammarus villosus was recorded for the first time in Lithuanian waters in 2015. The species was detected in three sites in the Curonian Lagoon (on two buoys in the lagoon strait and the harbour, and one littoral sampling site) and in the mouth of the Šventoji River. The species presence in the buoy fouling suggests the involvement of shipping in species introduction. Most likely D. villosus has arrived to the Curonian Lagoon with commercial ships, while the invasion into the mouth of the Šventoji River may be associated with leisure shipping as the port situated therein is not currently functioning. Further northward expansion of the killer shrimp in the Baltic Sea basin seems very probable. As the species is highly aggressive, alterations of local macroinvertebrate assemblages can also be predicted.
full, complete article - PDF (1542 K)