1. bookVolume 51 (2022): Issue 2 (June 2022)
Journal Details
License
Format
Journal
eISSN
1897-3191
First Published
23 Feb 2007
Publication timeframe
4 times per year
Languages
English
access type Open Access

Biodiversity of the benthic diatom flora in the coastal zone of the Gulf of Gdańsk: a case study of the Gdynia–Sopot transect

Published Online: 07 Jul 2022
Volume & Issue: Volume 51 (2022) - Issue 2 (June 2022)
Page range: 224 - 238
Received: 04 Nov 2021
Accepted: 20 Apr 2022
Journal Details
License
Format
Journal
eISSN
1897-3191
First Published
23 Feb 2007
Publication timeframe
4 times per year
Languages
English
Abstract

The objective of this study is to determine microhabitat preferences of benthic species occurring in epilithic (living on stones), epipsammic (growing on sand), epipelic (growing on mud) and epiphytic (living on seagrass) assemblages of the shallows of the Gulf of Gdańsk (southern Baltic Sea). The study material was collected from 19 sites along the Gdynia–Sopot coastal zone, including the Port of Gdynia. Most of the identified diatom taxa were observed in two or three microhabitats. However, diatom species living in only one type of microhabitat and those occurring in all analyzed microhabitats were also recorded. Autecological preferences of the identified diatoms indicate organic pollution of the coastal zone of Gdynia and Sopot. However, a higher frequency of α-mesosaprobionts and polysaprobionts indicates an increase in organic pollution in the Port of Gdynia and Marina Sopot, which is associated with intense port activity and large tourist traffic.

Key words

1. Introduction

Diatom research has been conducted in the Gulf of Gdańsk for nearly 100 years. The first researcher to document the occurrence of diatoms in the bay area was Schulz (1926). The modern and fossil diatom flora of the Gulf of Gdańsk was described by, among others, Rumek (1948), Pliński (1987, 1988, 1990, 1995), Witkowski (1994), Witkowski & Pempkowiak (1995), Pliński & Kwiatkowski (1996), Stachura & Witkowski (1997), Witak (2000, 2002, 2010, 2013), Bogaczewicz-Adamczak et al. (2001), Witak et al. (2006, 2011), Witak & Dunder (2007), Leśniewska & Witak (2008, 2011), Pliński & Witkowski (2009, 2011, 2013a,b), Witak & Pędziński (2018), Pędziński & Witak (2019). Previous studies usually focused on diatoms preserved in the sediments in different parts of the Gulf of Gdańsk. The diatom research in the coastal zone of the Gulf of Gdańsk was used to determine the degree of water organic pollution (Bogaczewicz-Adamczak et al. 2001; Zgrundo & Bogaczewicz-Adamczak 2004) and to investigate diatom preferences with respect to habitat (Witak et al. 2020). An important aspect of many diatom studies is to determine the degree of anthropogenic eutrophication. A multifaceted discussion on the relationship between diatoms and eutrophication in the Gulf of Gdańsk was included in the works of Witkowski (1994), Stachura & Witkowski (1997), Witak (2010, 2013), Leśniewska & Witak (2011), Witak & Pędziński (2018) and Pędziński & Witak (2019). Consequently, the so-called anthropogenic assemblage dominated by small planktic diatoms tolerating high levels of nitrogen, phosphorous and organic matter was defined, represented by Cyclotella meneghiniana Kützing, C. atomus Hustedt, C. choctawhatcheeana (Prasad in Prasad) Neinow & Livingston and Thalassiosira levanderi Van Goor (Witkowski 1994; Witak 2010, 2013; Witak & Pędziński 2018; Pędziński & Witak 2019). In addition, Catenula adhaerens (Mereschkowsky) Mereschkowsky, Cocconeis neothumensis Krammer, Fragilaria atomus Hustedt, Gedaniella guenter-grasii (Witkowski et Lange-Bertalot) Li, Sato & Witkowski and Pseudostaurosira brevistriata (Grunow) Williams & Round are frequently observed among the benthic species in eutrophic waters (Leśniewska & Witak 2008, 2011; Witak 2010, 2013).

The latest research on species diversity of epilithon, epipsammon and epiphyton was conducted in the inner coastal zone of the Hel Peninsula (Witak et al. 2020). That study has shown that diatom taphocoenoses are represented by species that prefer one type of microhabitat: epilithon is characterized by the presence of Denticula creticola (Østrup) Lange-Bertalot & Krammer and Diatoma tenuis C. Agardh, the epipsammic community contained Catenula adhaerens and Navicula germanopolonica Witkowski & Lange-Bertalot, while epiphyton was represented by Cocconeis pediculus Ehrenberg, Gomphonema olivaceum (Hornemann) Ehrenberg and Mastogloia pumila (Grunow) Cleve. The study has also shown that some species, despite being assigned to a specific microhabitat in the literature, can also be present in large numbers in various types of microhabitats. Such species include, among others, Halamphora coffeaeformis (C. Agardh) Mereschkowsky, Nitzschia frustulum (Kützing) Grunow, Rhoicosphaenia abbreviata (C. Agardh) Lange-Bertalot and Tabularia fasciculata (C. Agardh) Williams & Round. Despite many years of research on diatoms in the coastal zone of the Gulf of Gdańsk, knowledge about the relationship between the species composition of benthic diatoms and microhabitats requires further investigation. It is necessary to obtain microhabitat data for diatom taxa. The current global warming will be the cause of rising water levels in the world ocean. It will also cause sediment facies changes in the coastal zone. The past climatic changes have been recorded in the postglacial sediments of the Gulf of Gdańsk. Holocene climate fluctuations have resulted in the development of subsequent phases of the Baltic Sea evolution, evident also in the Gulf of Gdańsk. Diatoms, being sensitive to numerous environmental factors, are excellent bioindicators of Holocene salinity changes. The early Holocene decrease in salinity during the Ancylus Lake stage has resulted in a higher frequency of freshwater species (Witak et al. 2006; Witak & Jankowska 2014). The middle Holocene marine transgression in the initial phase of the Littorina Sea stage is well documented by the peak occurrence of marine planktic diatoms (Witkowski & Miller 1999; Witak et al. 2006; Leśniewska & Witak 2008; Witak 2010, 2013). The last stage of the Baltic Sea, the so called Post-Littorina Sea, is characterized by a decline in the frequency of euhalobous species (Witkowski 1994; Witak 2013). Diatoms are also great indicators of changes in the content of nutrients in water. Therefore, they testify to changes in trophic and saprobic status resulting from the inflow of river waters (Bogaczewicz-Adamczak et al. 2001; Zgrundo & Bogaczewicz-Adamczak 2004). Against the background of the well-established knowledge of changes in the structure of diatom assemblages in relation to salinity, trophic and saprobic status, information is needed on the benthic flora in relation to microhabitats. The objective of this study is to examine the taxonomic and ecological diversity of benthic diatom communities inhabiting various microhabitats in relation to environmental conditions modified by human influence.

2. Study area

The study area is located in the coastal zone of the south-western part of the Gulf of Gdańsk, the southern Baltic Sea. This region includes shallows with a depth not exceeding 30 cm b.s.l. along the shore between Gdynia and Sopot, as well as an area of deeper water in the Port of Gdynia dredged to ca. 16 m b.s.l (Fig. 1). Three types of coasts occur in the area, i.e. accumulative, cliffs and anthropogenic. The northern section represents the anthropogenic coast and comprises the Port of Gdynia and the Seaside Boulevard with a concrete revetment. The central part of the analyzed fragment of the coastal zone has the form of a cliff. This part of the shore is exposed to the intense erosive action of waves, which results in the presence of the Orłowo Cliff with the most seaward jutting Orłowo Headland, which constitutes a conventional border between Puck Bay and the open part of the Gulf of Gdańsk. To the south, the cliff is cut off by the Kacza River. This part of the shore features anthropogenic elements in the form of hydrotechnical structures, i.e. a pier and spurs. The southern part, located between the mouth of the Kolibianka River and the mouth of the Vistula River outside the city of Gdańsk, has an accumulative character. In the Sopot area there is a wide sand beach. Nevertheless, hydrotechnical structures such as the pier and spurs largely affect the hydrodynamics of this part of the bay (Basiński et al. 1993).

Figure 1

Location of the study area

The hydrological regime of the coastal zone of the Gulf of Gdańsk is determined by shallow water depth, climatic conditions, and the inflow of saline waters from the open sea. In addition, freshwater discharge from the surrounding land is an important factor influencing the hydrology of the study area. The deeper part of the Gulf of Gdańsk is controlled by the strong runoff from the Vistula mouth (Kravtsov et al. 2002). The influence of the Vistula River in the coast between Gdynia and Sopot is strongly limited due to prevailing winds blowing from the W, WNW and WSW directions, which distribute river water in an easterly direction. On the other hand, winds blowing from the E, ENE and ESE directions cause the Vistula runoff to move westward. The impact of the Vistula waters in the study area increases during extreme floods when the flood wave can reach up to 27 km from the mouth of the Vistula (Wielgat-Rychert et al. 2013). Moreover, the waters of the Vistula have the greatest impact on the nutrient load in the Gulf of Gdańsk. They introduce 90% of nitrogen and 81% of phosphorus (Andurlewicz & Witek 2002). However, the content of nutrients in the coastal zone of the Gulf of Gdańsk is significantly affected by industry (0.3% N, 0.9% P) and wastewater treatment plants (3% N, 3% P; Andurlewicz & Witek 2002). The impact of other rivers and streams, including the Kacza, the Chylonka, the Kolibianka, the Swelinia and the Karlikowski Stream is limited to the proximity of their outlets (Majewski 1972). The Baltic Sea monitoring studies conducted in 2010–2020 showed that the concentrations of total phosphorus and total nitrogen were lower in 2020 than in previous years (Drgas 2021).

Rivers provide warm water in summer and cool water in winter. On the other hand, seawater from the Gdańsk Basin have the opposite effect and cause temperature increase in winter and decrease in summer (Nowacki 1993a). Moreover, thermal conditions of the waters in the study area are strictly dependent on changes in air temperature in particular seasons. Long-term studies show the advantage of higher water temperatures compared to air temperature from August to January. The opposite trend is observed from March to June. Moreover, two compensations for temperature differences are noticeable. The first one occurs in February and the second one in July (Kwiecień 1990). The lowest air temperatures in the coastal zone of the south-western Gulf of Gdańsk are recorded in January and range from –1°C to –2°C, while the highest extreme values occur in August (ca. 28°C; Kwiecień 1990). At the same time, the surface water temperature reaches the lowest values in February (ca. 0°C) and the highest values in August (ca. 24°C; Herman 2021). The average water temperature in the coastal zone between Gdynia and Sopot from December to April (cold season) is 2.5–3.0°C. In the warm season, the temperature increases from 15.6–16.0°C in the vicinity of river mouths to 15.1–15.5°C in the area of the Port of Gdynia (Urbański et al. 2007). Seasonal changes in salinity are also observed. The average salinity in the cold season near the port and the Orłowo Headland is 7.59–7.75 PSU. In the coastal zone of Sopot, the salinity increases to 7.76–7.78 PSU. In the warm season, the salinity of 7.38–7.49 PSU is observed in almost all parts of the coastal zone of Gdynia and Sopot. Only in the area of the Orłowo Headland, the salinity drops to the value of 7.18–7.37 PSU due to the inflow of the Kacza River (Urbański et al. 2007).

The water circulation in the Gulf of Gdańsk is determined by the shape of the coastal zone and the frequent occurrence of winds from the western sector (Kowalik 1990). The basin is dominated by clockwise currents with an average speed of about 10 cm s-1 (Nowacki 1993b). The westerly winds cause the formation of currents that bring water from the outer side of the Hel Peninsula to the eastern side of the Gulf of Gdańsk. The coastal zone is characterized by the propagation of currents parallel to the shore (Kowalik 1990). There are also bottom currents, the direction of which is opposite to the surface currents and their speed is about 4 cm s-1 (Nowacki 1993b).

The bottom of the shallow-water zone of the Gulf of Gdańsk is mainly composed of sandy sediments (Kramarska 1995). In the Port of Gdynia, there are fine-grained sands and muds. In the marina, on the other hand, there are silty sands (Urbański et al. 2007). The remaining part of the studied coastal zone is covered with very well-sorted fine-grained sand. Less sorted sediments, represented by coarse sand, gravel and stones, occur only in the area of the Orłowo Cliff (Majewski 1990). The content of organic matter in sandy sediments is low and does not exceed 1%. However, in the mouth of the Kacza River, it increases to 5% (Majewski 1990).

The flora near the seabed of the coastal zone of the Gulf of Gdańsk is not rich and usually occurs to a depth of 8 m (Ringer 1990). However, high biodiversity is typical of the shallow-water region along a coastal cliff moraine plateau called Kępa Redłowska, where 17 species of macroalgae were identified (Pliński & Florczyk 1993). Numerous species of red algae – Ceramium diaphanum (Lightfoot) Roth, Furcellaria lumbricalis (Hudson) Lamouroux, green algae – Cladophora sp. Kützing and brown algae – Sphacellaria radicans (Dillwyn) C. Agardh have been observed in this area (Kruk-Dowgiałło et al. 2009). A valuable macroalga occurring along Kępa Redłowska is Zostera marina Linnaeus, which is the only species of seagrass observed in the Baltic Sea. This species is often found in the northern part of Puck Bay along the Hel Peninsula (Kruk-Dowgiałło & Opioła 2001; Witak et al. 2020). Until the late 1950s, Zostera marina was an important component of the underwater meadows. Since the late 1960s, a gradual decline of this species has been observed. However, studies conducted at the turn of the 20th and 21st centuries indicate a gradual recovery of the Zostera marina population in Puck Bay (Jankowska 2017).

3. Materials and methods

The material studied was collected in July 2016 along the coastal zone of the Gulf of Gdańsk from the Port of Gdynia up to the city limits of Sopot. A total of 19 sites were surveyed, including six sites in the Port of Gdynia (sites GaH1–6), eight sites along the coastal zone of Gdynia (sites Ga1–8) and five sites along the coastal zone of Sopot (sites So1–5; Fig. 1). Four samples were collected at site Ga2 (Ga2a,b,c,d), and two samples each were collected at sites Ga3 (Ga3a,b) and So1 (So1a,b; Table 1). At most sites, the diatom flora was analyzed from several microhabitats. At five sites (Ga2–3, Ga6–8), the study material was collected from stones. Sand was collected at five sites in Gdynia (Ga1–2, Ga5, Ga7–8) and four sites in Sopot (So1–2, So4–5). Muddy sediments were collected only in the Port of Gdynia (GaH1–6). Seagrasses were collected at 13 sites (Ga1–8, So1–5). A total of 37 samples were analyzed.

Characteristics of the analyzed samples. Types of microhabitats: st – stone, sa – sand, mu – mud, sg – seagrass. Black dots represent single samples collected

Sites Samples Φ λ Location Depth [m] Types of microhabitats
st sa mu sg
GaH1 GaHl 54°32.523N 18°30.32E GDYNIA PORT port channel 13.6      
GaH2 GaH2 54°32.30N 18°31.20E Dock VII 15.6      
GaH3 GaH3 54°32.10N 18°31.85E port channel 12.3      
GaH4 GaH4 54°31.85N 18°33.27E Dock III 14.4      
GaH5 GaH5 54°31.70N 18°33.62E south channel 8.7      
GaH6 GaH6 54°31.26N 18°33.50E Dock I 9.2      
Ga1 Ga1 54°30.999N 18°33.138E GDYNIA beach 0.25    
Ga2 Ga2a 54°30.774N 18°33.062E 0.25  
Ga2b      
Ga2c      
Ga2d      
Ga3 Ga3a 54°30.573N 18°33.203E Seaside Boulevard 0.3      
Ga3b      
Ga4 Ga4 54°30.499N 18°33.258E 0.3      
Ga5 Ga5 54°30.333N 18°33.412E 0.3    
Ga6 Ga6 54°30.147N 18°33.527E 0.3    
Ga7 Ga7 54°29.101N 18°34.118E beach 0.3  
Ga8 Ga8 54°28.788N 18°33.834E pier 0.2  
So1 So1a 54°27.057N 18°34.062E SOPOT beach 0.3    
So1b      
So2 So2 54°26.811N 18°34.345E pier 0.25    
So3 So3 54°26.447N 18°34.636E beach 0.3      
So4 So4 54°26.115N 18°35.051E 0.24    
So5 So5 54°25.666N 18°35.751E 0.27    

Diatom samples containing live cells were prepared according to the standard procedure of Battarbee (1986). All samples were treated with 30% H2O2 to remove organic matter. However, sediment samples (ca. 0.5–1 g of dry sediment) were previously treated with 10% HCl to remove calcium carbonate. Quantitative diatom analysis was carried out on all samples. Moreover, qualitative analysis was performed on sandy and muddy sediments. The random settling technique was used to estimate the concentration of diatom valves per unit weight of dry sediment (Bodén 1991). Permanent diatom preparations were mounted in Naphrax with a refractive index nD of 1.73. The analysis was performed under a Nikon ECLIPSE E200 light microscope at a magnification of ×100, using oil immersion. Only whole, undamaged diatom valves were considered for counting. The counting method of Schrader and Gersonde (1978) was applied, and ca. 300–500 valves in each sample were counted to estimate relative abundance of each taxon. Row counts were converted into relative abundance of all valves counted. The following identification keys were used to identify diatoms: Hustedt (1927–1966), Krammer & Lange-Bertalot (1986, 1988, 1991a,b), Pankow (1990), Krammer (2000), Lange-Bertalot (2001), Bąk et al. (2012). In addition, the identified diatoms were classified with respect to their autoecological preferences, including microhabitat, salinity, trophic and saprobic status, which was completed based on OMNIDIA 6.08 software. All details of ecological groupings were presented by Witak et al. (2020). In the case of some marine and brackish water species, trophic and saprobic preferences are irrelevant. The percentage content of all ecological groups was estimated in each sample. Only species with frequency exceeding 3% in at least one sample were selected for diatom diagrams prepared using TILIA 2.0.37 (Grimm 2011).

4. Results

A total of 147 species, subspecies, varieties and forms belonging to 56 genera were identified in the material studied (Fig. 2). Epipelic diatoms were the most diverse group, represented by 86 species. Epilithic and epiphytic diatoms were less diverse, with 68 and 71 species identified in these groups, respectively. The lowest diversity, 68 species, was observed in the epipsammic community.

Figure 2

The number of diatom taxa (species, subspecies, varieties, forms) versus ecological preferences: *eh-euhalobous, mh-mesohalobous, oh–oligohalobous halophilous, oi–oligohalobous indifferent; **et–eutraphentic, emt–eumesotraphentic, mt–mesotraphentic, mot-meso-oligotraphentic, ot–oligotraphentic, edt–eurydystrophic, ir-irrelevant; ***ps–polysaprobous, ams–α-mesosaprobous, abms–α-β-mesosaprobous, bms–β-mesosaprobous, os– oligosaprobous, x-xenosaprobous, ir-irrelevant

Diatom taphocoenoses of the shallow coastal zone of the Gulf of Gdańsk are usually dominated by benthic species. Planktic species constituted the allochthonous element of the studied material. The exception is muddy sediments in the Port of Gdynia, where epipelon is mainly represented by planktic species with frequency reaching 80%. This group was predominantly represented by eutraphentic diatoms, including Thalassiosira levanderi, Cyclotella choctawhatcheeana and Stephanodiscus hantzschii Grunow. All these species belong to the so-called anthropogenic assemblage reported by Witkowski (1994), Witak (2010, 2013), Witak & Pędziński (2018), Pędziński & Witak (2019). In the epipsammic community, plankton occurs rarely, with a higher content of Cyclotella atomus and Lindavia radiosa (Grunow) De Toni & Forti at sites Ga5 and Ga7. The lowest frequency of planktic species (up to 1%) was observed in the epilithic and epiphytic community.

4.1. Epilithon

In the Gdynia region, oligohalobous halophilous, eutraphentic and β-mesosaprobic diatoms predominate in the epilithon. Their frequency usually exceeds 80% (Fig. 3). However, at the mouth of the Kacza River (Ga8), the frequency of β-mesosaprobionts drops to ca. 40%. At the same time, the percentage of α-mesosaprobionts increases to ca. 40%. Diatoms growing on stones (Gdynia sites) were usually dominated by the species Diatoma moniliformis (Kützing) Williams, the frequency of which ranged from 19% (Ga2a) to 88% (Ga3b; Fig. 4). The α-mesosaprobic species Rhoicosphaenia abbreviata with a frequency of ca. 19% and the polysaprobiont Navicula perminuta Grunow (≤ 5%) were recorded at almost all Gdynia sites. Only at site Ga2a the frequency of N. perminuta did not exceed 3%. Freshwater diatoms represented by Cocconeis pediculus, Epithemia sorex Kützing, Rhopalodia gibba var. gibba (Ehrenberg) O. Müller and R. gibba var. minuta Krammer occurred sporadically. However, their percentage increases to 3–10% at site Ga2a, and they are accompanied by marine and brackish diatoms, i.e. Bacillaria paxillifera (O. F. Müller) Marsson, Gedaniella mutabilis (Grunow) Li & Witkowski, Grammatophora marina (Lyngbye) Kützing, G. oceanica Ehrenberg, Melosira moniliformis C. Agardh, M. nummuloides C. Agardh, Tabularia fasciculata. Moreover, at site Ga6, Nitzschia frustulum reaches a frequency of ca. 39%.

Figure 3

Percentage content of the diatom ecological groups in epilithon (stone), epipsammon (sand) and epipelon (mud)

Figure 4

Frequency of the main diatom taxa in epilithon (stone), epipsammon (sand) and epipelon (mud)

4.2. Epipsammon

The epipsammic assemblage of the Gdynia and Sopot zone is dominated by eutraphentic diatoms with a maximum frequency of 78% at site Ga8 (Fig. 3). They were accompanied by eu-mesotraphentic species (7–35%). The percentage of saline groups indicates a slightly higher frequency of mesohalobous diatoms at the Sopot sites than in Gdynia. The brackish species Planothidium delicatulum (Kützing) Round & Bukhtiyarova (Fig. 4), belonging to eutraphents and β-mesosaprobionts, was frequently recorded. This species was particularly abundant in the marina in Gdynia (Ga1–2a) and in Sopot (So1a–2, So4–5). At these sites, a higher percentage of eu-mesotraphentic species was observed, i.e. Amphora pediculus (Kützing) Grunow, Planothidium lemmermannii (Hustedt) E.Morales and Staurosira venter (Ehrenberg) Cleve & Möller and the meso-oligotraphentic species Navicula paul-schulzii Witkowski & Lange-Bertalot. Among the brackish diatoms, Fallacia clepsidroides Witkowski, Fragilaria cassubica Witkowski & Lange-Bertalot, F. gedanensis Witkowski, Navicula germanopolonica occurred more frequently. A slightly different flora inhabits the sands in the Orłowo Cliff area (Ga7–8). In the epipsammon, oligohalobous halophilous and indifferent species, mainly those preferring waters rich in nutrients and organic matter, were more frequently observed. This group is represented by C. placentula Ehrenberg, Epithemia sorex, E. turgida (Ehrenberg) Kützing, Rhoicosphaenia abbreviata, and Rhopalodia gibba var. gibba. The highest concentration of valves in sandy sediments was recorded in the marina area (48 x 105 valves/g). Between sites Ga5 and Ga8, the concentration decreases (2 x 105 valves/g) and then increases in Sopot (17 x 105 valves/g; Fig. 3).

4.3. Epipelon

The epipelic assemblage found only in the Port of Gdynia (GH1–8) was dominated by eutraphentic (49–82%) and α- and β-mesosaprobic diatoms (10–30% and 10–35%, respectively; Fig. 3). The concentration of diatom valves is clearly higher in the port muds than in the sandy sediments of Gdynia and Sopot and ranges between 25 x 105 valves/g (GaH5) and 75 x 105 valves/g (GaH1). The marine species Nanofrustulum krumbeinii (Witkowski, Witak & Stachura) E. Morales has a higher frequency in the eutraphentic benthos, with a maximum at site GaH3 (34%; Fig. 4). It is accompanied by other marine diatoms, i.e. Bacillaria paxillifera, Catenula adhaerens and many brackish species, i.e. Gedaniella mutabilis, Martyana schulzii C. Brockmann, M. atomus, Planothidium delicatulum, Tabularia fasciculata. In the northern part of the port, a higher frequency of the freshwater species Diatoma tenuis is observed. Whereas in the southern part of the Port of Gdynia, the frequency of the freshwater species Staurosira venter increased.

4.4. Epiphyton

The epiphytic assemblage occurring at all sites in Gdynia and Sopot, except the port, is dominated by diatoms preferring nutrient-rich waters (70–98%) and tolerating large amounts of organic matter, i.e. α- and β-mesosaprobionts (33–91%, 7–62% respectively; Fig. 5). Between sites Ga1 and So1, the epiphytic assemblage is dominated by oligohalobous halophilous species, i.e. Diatoma moniliformis, Epithemia sorex and Rhoicosphaenia abbreviata (Fig. 6). Furthermore, the oligohalobous-indifferent species Cocconeis pediculus is also found there. The eu- and mesohalobous species, i.e. Grammatophora marina, G. oceanica, Melosira moniliformis and M. nummuloides are of lesser importance. At sites So2–5, mesohalobous species play a key role in diatom assemblages. This group is mostly represented by Tabularia fasciculata (35–67%), which is accompanied by Bacillaria paxillifera and Navicula perminuta.

Figure 5

Percentage content of the diatom ecological groups in epiphyton (seagrass)

Figure 6

Frequency of the main diatom taxa in epiphyton (seagrass)

5. Discussion
5.1. Diatoms versus microhabitats

Our results have shown significant differences in species spectra in relation to microhabitats. Changes in saline conditions caused by the inflow of river waters as well as anthropopressure had a significant impact on the species diversity of the diatom flora. The observed differences in individual diatom communities (epilithic, epipsammic, epipelic and epiphytic) allowed us to distinguish four groups: (1) species characteristic of one microhabitat, (2) species living in two types of microhabitats, (3) species observed in three microhabitats, and (4) species occurring in all types of microhabitats.

5.1.1. One microhabitat

Some diatom species were found in only one of the analyzed communities (epipsammon, epipelon, epiphyton). Karayevia clevei (Grunow) Bukhtiyarova and Epithemia turgida occurred only on sandy microhabitats in the study area (sites Ga1, Ga7–Ga8, So1a, So5 and Ga7–Ga8, respectively). The latter species is described as an epiphytic form (e.g. Snoeijs & Potapova 1995). Cocconeis neothumensis recorded in the study material with epipsammon (Snoeijs & Balashova 1998) was frequently observed at site So2. However, it was also observed in sandy muds of the Gulf of Gdańsk by Leśniewska & Witak (2008), Witak (2010) and Witak & Pędziński (2018). Nanofrustulum krumbeinii is a species recorded only in the epipelon of the coastal zone of the Gulf of Gdańsk (sites GaH1– GaH6). This small benthic diatom was also abundant in epilithic and epipsammic communities in the inner coastal zone of the Hel Peninsula between Jurata and Chałupy (Witak et al. 2020), as well as in muddy and sandy sediments of the Gulf of Gdańsk (Witak 2010; Leśniewska & Witak 2011; Pędziński &Witak 2019). Moreover, two species, Ctenophora pulchella (Ralfs ex Kützing) Williams & Round (site So2) and Cocconeis euglypta Ehrenberg (sites Ga2a and So2), were recorded only in the epiphytic community. Both taxa were also abundant in the epiphyton of the coastal zone from the Hel Cape to Chałupy (Witak et al. 2020). Further, C. euglypta was often observed in the epilithic assemblage near Kuźnica.

5.1.2. Two microhabitats

Three groups were distinguished among the diatoms occurring in two microhabitats. The first group represented by Rhopalodia gibba var. minuta, Grammatophora marina and Melosira moniliformis is associated with epilithon and epiphyton. These species were more frequently observed in the epiphytic assemblage than in the epilithic community. This group also included Grammatophora oceanica and Melosira nummuloides, which were reported by Pliński & Witkowski (2011) and Witkowski (1994) in epiphytic assemblages of shallows in the Gulf of Gdańsk. The second group consisted of species connected with epipsammon and epipelon such as Fragilaria cassubica, F. gedanensis Witkowski, Martyana schulzii Brockmann, M. atomus. All mentioned taxa were reported by Snoeijs & Potapova (1995), Witkowski (1994), Witkowski et al. (2000) and Pliński & Witkowski (2011, 2013) in the epipsammic community. Furthermore, Amphora pediculus, Catenula adhaerens, Navicula gregaria Donkin, Navicula paul-schulzii and Navicula germanopolonica, which are commonly observed in muddy and sandy sediments of the Gulf of Gdańsk, were recorded in this group (Witak & Dunder 2007; Witak 2010, 2013; Leśniewska & Witak 2011; Witak & Pędziński 2018; Witak et al. 2020). The presence of Planothidium delicatulum and Staurosira venter is also characteristic for this community. Both species are abundant in sands and muds in different regions of the Gulf of Gdańsk and the Vistula Lagoon (Witak & Dunder 2007; Leśniewska & Witak 2008; Witak 2010; Witak & Pędziński 2018). However, they were also recorded on seagrasses and stones along the inner side of the Hel Peninsula (Witak et al. 2020). The species Fallacia clepsidroides, which was reported by Snoeijs & Potapova (1995) as an epipelic form, was also found in epipsammic and epipelic assemblages. Along the Hel Peninsula it was observed in epilithon and more often in epipsammon (Witak et al. 2020). The last group is related to the species Tabularia tabulata (C. Agardh) Snoeijs occurring in muddy sediments and seagrasses in the study area, which was observed in the largest numbers in the epiphyton (Ga1–Ga2b). This species was reported in the epiphytic community by Snoeijs (1993).

5.1.3. Three microhabitats

The species Diatoma moniliformis was observed in epilithon, epiphyton and epipelon. It reaches the highest frequency in the epilithon along the coastal zone of Gdynia (Ga2–Ga8). The species was most abundant in the epiphyton of the Hel Peninsula (Witak et al. 2020), where it was also observed in epilithon and epipsammon (Witak et al. 2020). Diatoma tenuis, defined by Snoeijs (1993) as an epiphytic species, was recorded in epipsammon, epipelon and epiphyton. The species occurred in the epilithic community in the inner side of the Hel Peninsula (Witak et al. 2020). The third group, represented by Rhopalodia gibba var. gibba, is associated with the epipsammic, epilithic and epiphytic community, but thrives most abundantly on seagrasses. The last group of diatoms, which was associated with epipsammon, epipelon and epilithon was marked by the presence of the species Gedaniella mutabilis, commonly observed in sandy and muddy sediments of Puck Bay and the Vistula Lagoon (Witak 2010, 2013; Witak & Pędziński 2018).

5.1.4. All microhabitats

Diatoms occurring in all types of microhabitats are represented by the species reported by Snoeijs (1993) in the epilithon (Bacillaria paxillifera, Nitzschia frustulum, Navicula perminuta) and epiphyton (Cocconeis pediculus, Epithemia sorex, Tabularia fasciculata). This group also includes Rhoicosphaenia abbreviata and Tabularia fasciculata, which were observed in all types of microhabitats along the Hel Peninsula (Witak et al. 2020). Several species, although occurring in all microhabitats, showed distinct preferences for one of them. Rhoicosphaenia abbreviata and Tabularia fasciculata predominate in the epiphytic community. The epilithic assemblage at site Ga6 shows an increase in the frequency of Nitzschia frustulum. This species is one of the main components of the diatom flora in all microhabitats of the inner Hel Peninsula (Witak et al. 2020). Moreover, epiphytic communities are characterized by a higher frequency of Epithemia sorex. In the epipsammic community, the most noteworthy sites are Ga7–8, where the frequency of Epithemia sorex and Rhoicosphaenia abbreviata increased. These species do not show a high affinity for the muddy microhabitat.

5.2. Diatoms versus location
5.2.1. Gdynia Port

The port of Gdynia is impacted by seawater of the Gulf of Gdańsk, which is well documented by the dominance of marine and brackish diatoms in the muddy sediments. Due to ship traffic and intensive port activity, the water column and bottom sediments contain a large number of organic pollutants. Diatom taphocoenoses in its north-western part (GaH1–2) are rich in polysaprobionts (≤ 44%) and β-mesosaprobionts (≤ 37%). Moreover, a higher frequency of the α-mesosaprobiont Diatoma tenuis, accompanied by Tabularia fasciculata and T. tabulata, is observed. The high level of organic matter in this area is related to the presence of a shipyard and the Baltic Container Terminal. The southern part of the Port of Gdynia (GaH4–6) is less contaminated with nutrients, which is indicated by the dominance of α- and β-mesosaprobionts, including frequently recorded Nanofrustulum krumbeinii. This species was commonly observed in the Gulf of Gdańsk (Leśniewska & Witak 2011; Pędziński & Witak 2019; Witak et al. 2020). The higher frequency of this benthic diatom is accompanied by an increase in the relative abundance of β-mesosaprobionts such as Gedaniella mutabilis and Staurosira venter. High organic pollution accumulated in the sediments of the Port of Gdynia is related to the composition of the sediment (Radke et al. 2013). The presence of a breakwater also has an unfavorable impact on the water state in the port. Despite its protective function, it has a negative impact on the environmental conditions due to the limitation of water exchange, which in turn does not allow the area to be cleaned of organic pollution with excessive amounts of nutrients. The relatively large depth of the Port of Gdynia contributes to the dominance of planktic anthropogenic species (Cyclotella choctawhatcheeana, Thalassiosira levanderi, Stephanodiscus hantzschii), which prefer high trophic requirements (Witak 2000, 2010; Leśniewska & Witak 2008, 2011; Witak & Pędziński 2018; Pędziński & Witak 2019).

5.2.2. Gdynia coastal zone

The inflow of water from the Kacza River has a significant impact on the salinity conditions in the this part of the coastal zone. The Kacza River is the second largest river flowing through the Tri-City (Augustowska et al. 1994). Between the marina (Ga1) and the Orłowo Headland (Ga8), brackish diatoms (Fallacia clepsidroides, Planothidium delicatulum) are gradually replaced by oligohalobous halophilous diatoms in epiphyton, epilithon and epipsammon, i.e. Diatoma moniliformis, Epithemia sorex, Rhoicosphaenia abbreviata. All the above-mentioned taxa were observed in different regions of the Gulf of Gdańsk (Witak 2010; Witak et al. 2020). As in the Port of Gdynia, the dominance of species with high trophic requirements is observed, including Diatoma moniliformis, Epithemia sorex, Planothidium delicatulum, Rhoicosphaenia abbreviata. Eutraphentic species constitute ≤ 98% in the epilithic and epiphytic community, while in the epipsammon they account for ≤ 76%. The high content of biogenic substances in this part of the coastal zone is related to urbanization. The higher frequency of polysaprobionts in the epipsammon (≤ 34%) in the northern part of the zone indicates a high content of organic matter in the vicinity of the marina (Ga1, Ga2a) and Seaside Boulevard (Ga5). Toward the south, the level of saprobity is lower, which is well documented by an increase in the frequency of α- and β-mesosaprobionts in the epilithic (≤ 47%, ≤ 95%), epiphytic (≤ 75%, ≤ 62%) and epipsammic community (≤ 25%, ≤ 38%).

5.2.3. Sopot coastal zone

The hydrological regime of the coastal zone in Sopot is influenced by saline waters of the Gulf of Gdańsk. This is evidenced by the dominance of eutraphentic mesohalobous, represented mostly by Bacillaria paxillifera, Planothidium delicatulum and Tabularia fasciculata. Their particularly high frequency is observed in epipsammon (≤ 62%) and epiphyton (≤ 77%). Other brackish diatoms, i.e. Fallacia clepsidroides, Fragilaria cassubica, F. gedanensis, Navicula paul-schulzii and N. germanopolonica were rarely observed. Abundance of oligohalobous halophilous taxa (Diatoma moniliformis, Planothidium lemmermannii, Rhoicosphaenia abbreviata) was recorded at sites So1 and So3–4, which is related to the influence of the Swelinia and Karlikowski streams. Moreover, representatives of oligohalobous indifferent diatoms (Amphora pediculus, Diatoma moniliformis and Nitzschia frustulum) were observed in taphocoenoses. These diatoms were also recorded at the mouth of nearby streams by Bogaczewicz-Adamczak et al. (2001) and Zgrundo & Bogaczewicz-Adamczak (2004). The presence of polysaprobionts and the abundance of α-mesosaprobionts, particularly in epiphytic assemblages, indicate a higher content of organic matter in the Sopot coastal zone, which is associated with high tourist traffic and close proximity to the urbanized zone.

6. Conclusions

The results of the diatom study in the coastal zone of the Gulf of Gdańsk, between Gdynia and Sopot, indicate the presence of a diverse flora belonging to epilithic, epipsammic, epipelic and epiphytic assemblages. Most of the identified benthic species occurred in two or three microhabitats:

Epilithon and epiphyton were represented by Rhopalodia gibba var. minuta, Grammatophora marina and Melosira moniliformis. Amphora pediculus, Catenula adhaerens, Fallacia clepsidroides, Fragilaria cassubica, F. gedanensis, F. schulzii, Martyana atomus, Navicula gregaria, N. paul-schulzii, N. germanopolonica, Planothidium delicatulum and Staurosira venter were observed in the material collected from sandy and muddy sediments. Tabularia tabulata was observed in epipelon and epiphyton.

The species Diatoma moniliformis was observed in epilithon, epiphyton and epipelon, while D. tenuis was associated with epipsammon, epipelon and epiphyton. The species Rhopalodia gibba var. gibba was associated with epipsammon, epilithon and epiphyton. Furthermore, epipsammon, epipelon and epilithon were represented by Gedaniella mutabilis.

However, considering the diatom–microhabitat relationships, two specific groups were distinguished:

Epipsammon, epipelon and epiphyton were characterized by the presence of at least one species that was not observed in other communities. The species Cocconeis neothumensis, Epithemia turgida and Karayevia clevei are typical of epipsammon, while Nanofrustulum krumbeinii was observed only in epipelon. Furthermore, two species, Ctenophora pulchella and Cocconeis euglypta, are characteristic of the epiphyton.

Some diatom species, i.e. Bacillaria paxillifera, Cocconeis pediculus, Epithemia sorex, Navicula perminuta, Nitzschia frustulum, Rhoicosphaenia abbreviata and Tabularia fasciculata were observed in all analyzed microhabitats, which means they do not have any preferences with respect to the type of substrate.

Based on the ecological preferences of the identified diatom flora, certain differences in the quality of water were observed in the Port of Gdynia and in the coastal zone of Gdynia and Sopot:

The high frequency of α-mesosaprobionts dominated by Bacillaria paxillifera, Rhoicosphaenia abbreviata and Tabularia fasciculata may indicate the high level of organic matter in the study area. The highest frequency of these species was mostly observed in epiphyton and epilithon. The increased organic pollution in the waters of the Port of Gdynia and the marina is evidenced by the abundance of polysaprobiont taxa such as benthic Navicula perminuta present in the epipsammon, epilithon and epiphyton. A higher frequency of polysaprobionts was observed in the coastal zone of Sopot, due to the high tourist traffic and urbanization of the coastal zone.

The high degree of eutrophication of the waters of the study area was evidenced by the abundance of species with high trophic requirements, represented by Bacillaria paxillifera, Diatoma moniliformis, Epithemia sorex, Nanofrustulum krumbeinii, Nitzschia frustulum, Planothidium delicatulum, Rhoicosphaenia abbreviata and Tabularia fasciculata.

The change in salinity in the study area is related to the distance from the mouths of nearby rivers and streams. Due to the limited water dynamics associated with the breakwater, the area of the Port of Gdynia is dominated by marine species, of which Nanofrustulum krumbeinii predominates. The frequency of brackish species (Navicula perminuta, Tabularia fasciculata, T. tabulata, Planothidium delicatulum) increases in the vicinity of the marina in Gdynia and in the coastal zone of Sopot. Moreover, a higher frequency of freshwater species (Amphora pediculus, Diatoma moniliformis, Epithemia sorex, Nitzschia frustulum, Rhoicosphaenia abbreviata) is observed near the mouths of the Kacza River, and the Swelinia and Karlikowski streams.

Figure 1

Location of the study area
Location of the study area

Figure 2

The number of diatom taxa (species, subspecies, varieties, forms) versus ecological preferences: *eh-euhalobous, mh-mesohalobous, oh–oligohalobous halophilous, oi–oligohalobous indifferent; **et–eutraphentic, emt–eumesotraphentic, mt–mesotraphentic, mot-meso-oligotraphentic, ot–oligotraphentic, edt–eurydystrophic, ir-irrelevant; ***ps–polysaprobous, ams–α-mesosaprobous, abms–α-β-mesosaprobous, bms–β-mesosaprobous, os– oligosaprobous, x-xenosaprobous, ir-irrelevant
The number of diatom taxa (species, subspecies, varieties, forms) versus ecological preferences: *eh-euhalobous, mh-mesohalobous, oh–oligohalobous halophilous, oi–oligohalobous indifferent; **et–eutraphentic, emt–eumesotraphentic, mt–mesotraphentic, mot-meso-oligotraphentic, ot–oligotraphentic, edt–eurydystrophic, ir-irrelevant; ***ps–polysaprobous, ams–α-mesosaprobous, abms–α-β-mesosaprobous, bms–β-mesosaprobous, os– oligosaprobous, x-xenosaprobous, ir-irrelevant

Figure 3

Percentage content of the diatom ecological groups in epilithon (stone), epipsammon (sand) and epipelon (mud)
Percentage content of the diatom ecological groups in epilithon (stone), epipsammon (sand) and epipelon (mud)

Figure 4

Frequency of the main diatom taxa in epilithon (stone), epipsammon (sand) and epipelon (mud)
Frequency of the main diatom taxa in epilithon (stone), epipsammon (sand) and epipelon (mud)

Figure 5

Percentage content of the diatom ecological groups in epiphyton (seagrass)
Percentage content of the diatom ecological groups in epiphyton (seagrass)

Figure 6

Frequency of the main diatom taxa in epiphyton (seagrass)
Frequency of the main diatom taxa in epiphyton (seagrass)

Characteristics of the analyzed samples. Types of microhabitats: st – stone, sa – sand, mu – mud, sg – seagrass. Black dots represent single samples collected

Sites Samples Φ λ Location Depth [m] Types of microhabitats
st sa mu sg
GaH1 GaHl 54°32.523N 18°30.32E GDYNIA PORT port channel 13.6      
GaH2 GaH2 54°32.30N 18°31.20E Dock VII 15.6      
GaH3 GaH3 54°32.10N 18°31.85E port channel 12.3      
GaH4 GaH4 54°31.85N 18°33.27E Dock III 14.4      
GaH5 GaH5 54°31.70N 18°33.62E south channel 8.7      
GaH6 GaH6 54°31.26N 18°33.50E Dock I 9.2      
Ga1 Ga1 54°30.999N 18°33.138E GDYNIA beach 0.25    
Ga2 Ga2a 54°30.774N 18°33.062E 0.25  
Ga2b      
Ga2c      
Ga2d      
Ga3 Ga3a 54°30.573N 18°33.203E Seaside Boulevard 0.3      
Ga3b      
Ga4 Ga4 54°30.499N 18°33.258E 0.3      
Ga5 Ga5 54°30.333N 18°33.412E 0.3    
Ga6 Ga6 54°30.147N 18°33.527E 0.3    
Ga7 Ga7 54°29.101N 18°34.118E beach 0.3  
Ga8 Ga8 54°28.788N 18°33.834E pier 0.2  
So1 So1a 54°27.057N 18°34.062E SOPOT beach 0.3    
So1b      
So2 So2 54°26.811N 18°34.345E pier 0.25    
So3 So3 54°26.447N 18°34.636E beach 0.3      
So4 So4 54°26.115N 18°35.051E 0.24    
So5 So5 54°25.666N 18°35.751E 0.27    

Andrulewicz, E., & Witek, Z. (2002). Anthropogenic pressure and environmental effects on the Gulf of Gdan’sk: recent management efforts. In G. Schernewski & U. Schiewer (Eds.), Baltic Coastal Ecosystems, Structure, Function and Coastal Zone Management (pp. 119–139). Springer. https://doi.org/10.1007/978-3-662-04769-9_9 Andrulewicz, E. , & Witek, Z. ( 2002 ). Anthropogenic pressure and environmental effects on the Gulf of Gdan’sk: recent management efforts . In G. Schernewski & U. Schiewer (Eds.), Baltic Coastal Ecosystems, Structure, Function and Coastal Zone Management (pp. 119 139 ). Springer . https://doi.org/10.1007/978-3-662-04769-9_9 10.1007/978-3-662-04769-9_9 Search in Google Scholar

Augustowska, M., Piliczewski, B. & Witoński, M. (1994). Rzeki Przymorza, Bałtycki Fund. Edukacji Ekologicznej: Morski Inst. Rybacki: Uniwersytet Gdański. (In Polish). Augustowska, M. Piliczewski, B. & Witoński, M. ( 1994 ). Rzeki Przymorza, Bałtycki Fund . Edukacji Ekologicznej : Morski Inst . Rybacki : Uniwersytet Gdański . (In Polish). Search in Google Scholar

Basiński, T., Pruszak, Z., Tarnowska, M., & Zeidler, R. (1993). Ochrona brzegów morskich. Instystut Budowsnictwa Wodnego PAN. (In Polish) Basiński, T. Pruszak, Z. Tarnowska, M. , & Zeidler, R. ( 1993 ). Ochrona brzegów morskich . Instystut Budowsnictwa Wodnego PAN . (In Polish) Search in Google Scholar

Battarbee, R. W. (1986). Diatom analysis. In B. E. Berglund (Ed.), Handbook of Holocene Palaeoecology and Palaeohydrology (pp. 527–570). John Wiley and sons. Ltd. Battarbee, R. W. ( 1986 ). Diatom analysis . In B. E. Berglund (Ed.), Handbook of Holocene Palaeoecology and Palaeohydrology (pp. 527 570 ). John Wiley and sons. Ltd. Search in Google Scholar

Bąk, M., Witkowski, A., Żelazna-Wieczorek, J., Wojtal, A. Z., Szczepocka, E., Szulc, K. & Szulc, B. (2012). Klucz do oznaczania okrzemek w fitobentosie na potrzeby oceny stanu ekologicznego wód powierzchniowych w Polsce. Warszawa –Główny inspektorat ochrony środowiska: 20-25. (In Polish). Bąk, M. Witkowski, A. Żelazna-Wieczorek, J. Wojtal, A. Z. Szczepocka, E. Szulc, K. & Szulc, B. ( 2012 ). Klucz do oznaczania okrzemek w fitobentosie na potrzeby oceny stanu ekologicznego wód powierzchniowych w Polsce . Warszawa –Główny inspektorat ochrony środowiska : 20 - 25 . (In Polish). Search in Google Scholar

Bodén, P. (1991). Reproducibility in the Random Settling Method for Quantitative Diatom Analysis. Micropaleontology, 37(3), 313–319. https://doi.org/10.2307/1485893 Bodén, P. ( 1991 ). Reproducibility in the Random Settling Method for Quantitative Diatom Analysis . Micropaleontology , 37 ( 3 ), 313 319 . https://doi.org/10.2307/1485893 10.2307/1485893 Search in Google Scholar

Bogaczewicz-Adamczak, B., Kłosińska, D., & Zgrundo, A. (2001). Diatoms as indicator of water pollution in the coastal zone of the Gulf of Gdańsk (Southern Baltic Sea). Oceanological Studies., 30(3), 59–75 Bogaczewicz-Adamczak, B. Kłosińska, D. , & Zgrundo, A. ( 2001 ). Diatoms as indicator of water pollution in the coastal zone of the Gulf of Gdańsk (Southern Baltic Sea) . Oceanological Studies. , 30 ( 3 ), 59 75 Search in Google Scholar

Cyberska, B. (1990). Temperatura wody, [w:] A. Majewski (red.), Zatoka Gdańska. Warszawa: IMGW, Wyd. Geologiczne: 187-204. (In Polish). Cyberska, B. ( 1990 ). Temperatura wody, [w:] A. Majewski (red.), Zatoka Gdańska . Warszawa : IMGW, Wyd. Geologiczne : 187 - 204 . (In Polish). Search in Google Scholar

Drgas, N. (2021). Ocena stanu środowiska Polskich obszarów morskich Bałtyku na podstawie danych monitoringowych z roku 2020 na tle dziesięciolecia 2010-2019. T. Zalewska, W. Kraśniewski (red). Główny Inspektorat Ochrony Środowiska. (In Polish) Drgas, N. ( 2021 ). Ocena stanu środowiska Polskich obszarów morskich Bałtyku na podstawie danych monitoringowych z roku 2020 na tle dziesięciolecia 2010-2019. T. Zalewska, W. Kraśniewski (red) . Główny Inspektorat Ochrony Środowiska . (In Polish) Search in Google Scholar

Grimm, E. C. (2011). Tilia Version 2.0.37 (software). Illinois State Museum. Grimm, E. C. ( 2011 ). Tilia Version 2.0.37 (software) . Illinois State Museum . Search in Google Scholar

Herman, A. (2021). Zlodzenie Zatoki Puckiej, Zatoka Pucka Tom I Aspekty geologiczne i fizyczne. J. Bolałek, D. Burska (red). Wyd. Uniwersytetu Gdańskiego. (In Polish) Herman, A. ( 2021 ). Zlodzenie Zatoki Puckiej, Zatoka Pucka Tom I Aspekty geologiczne i fizyczne. J. Bolałek, D. Burska (red) . Wyd. Uniwersytetu Gdańskiego . (In Polish) Search in Google Scholar

Hetko, D., Pędziński, J. & Witak, M. (2019). Response of the Diatom Flora of the Hel Peninsula Vicinity, Puck Bay, Baltic Sea, to Anthropopressure, IOP Conf. Ser.: Earth and Environmental Science 362 012050 (online). https://doi.org/10.1088/1755-1315/362/1/012050. Hetko, D. Pędziński, J. & Witak, M. ( 2019 ). Response of the Diatom Flora of the Hel Peninsula Vicinity, Puck Bay, Baltic Sea, to Anthropopressure , IOP Conf. Ser.: Earth and Environmental Science 362 012050 (online) . https://doi.org/10.1088/1755-1315/362/1/012050. 10.1088/1755-1315/362/1/012050 Search in Google Scholar

Hustedt, F. (1927–1966). Die Kieselalgen Deutschlands, Österreichs und der Schweiz 1-3. In Dr. L. Rabenhorsts (Ed.), Kryptogamen ora von Deutschland, Österreich und der Schweiz 7. Leipzig: Akademische Verlerlagsbuchhandlung. Hustedt, F. ( 1927–1966 ). Die Kieselalgen Deutschlands, Österreichs und der Schweiz 1-3 . In Dr. L. Rabenhorsts (Ed.), Kryptogamen ora von Deutschland, Österreich und der Schweiz 7 . Leipzig : Akademische Verlerlagsbuchhandlung . Search in Google Scholar

Jankowska, E. (2017). Structure and functioning of the benthic communities associated with macrophytes meadows in the Gulf of Gdańsk. Institute of Oceanology of Polish Academy of Sciences, Sopot (PhD thesis) Jankowska, E. ( 2017 ). Structure and functioning of the benthic communities associated with macrophytes meadows in the Gulf of Gdańsk . Institute of Oceanology of Polish Academy of Sciences, Sopot (PhD thesis) Search in Google Scholar

Kowalczuk, N. (1996). Distribution and species composition of benthic macroalgae community in the littoral zone at the Orłovo Cliff (the Gulf of Gdańsk, Baltic Sea), red. Styczyńska-Jurewicz E., Estuarine ecosystems and species, Proceedings of the 2-nd International Estuary Symposium held in Gdańsk, October 18-22, 1993, pp 143-149. Kowalczuk, N. ( 1996 ). Distribution and species composition of benthic macroalgae community in the littoral zone at the Orłovo Cliff (the Gulf of Gdańsk, Baltic Sea), red. Styczyńska-Jurewicz E., Estuarine ecosystems and species , Proceedings of the 2-nd International Estuary Symposium held in Gdańsk, October 18-22, 1993 , pp 143 - 149 . Search in Google Scholar

Kowalik, Z. (1990). Prądy (Currents). In A. Majewski (Ed.), Zatoka Gdańska (Gulf of Gdańsk). Warszawa: IMGW, Wyd. Geologiczne: 140 – 153. (In Polish) Kowalik, Z. ( 1990 ). Prądy (Currents) . In A. Majewski (Ed.), Zatoka Gdańska (Gulf of Gdańsk) . Warszawa : IMGW, Wyd. Geologiczne : 140 153 . (In Polish) Search in Google Scholar

Kramarska, R. (1995). Superficial bottom sediments. Pl. XXIV. In R. Dadlez, J.E. Mojski, B. Słowańska, S. Uścinowicz & J. Zachowicz (Eds), Geological atlas of the Southern Baltic, 1:500 000. Sopot – Warszawa: Państwowy Instytut Geologiczny Kramarska, R. ( 1995 ). Superficial bottom sediments. Pl. XXIV . In R. Dadlez J.E. Mojski B. Słowańska S. Uścinowicz & J. Zachowicz (Eds), Geological atlas of the Southern Baltic, 1:500 000 . Sopot – Warszawa : Państwowy Instytut Geologiczny Search in Google Scholar

Krammer, K. (2000) Diatoms of Europe. Vol. 1: The Genus Pinnularia. A.R.G. Gantner Verlag. Kommanditgesellschaft, Königstein, 1-703. http://dx.doi. org/10.1023/A:1008914531485 Krammer, K. ( 2000 ) Diatoms of Europe. Vol. 1: The Genus Pinnularia . A.R.G. Gantner Verlag. Kommanditgesellschaft, Königstein , 1 - 703 . http://dx.doi.org/10.1023/A:1008914531485 Search in Google Scholar

Krammer, K., & Lange-Bertalot, H. (1986). Bacillariophyceae. 1. Teil: Naviculaceae. In H. Ettl, J. Gerloff, H. Heynig, & D. Mollenhauer (Eds.), Süßwasserflora von Mitteleuropa 2/1 (p. 876). G. Fischer. Krammer, K. , & Lange-Bertalot, H. ( 1986 ). Bacillariophyceae. 1. Teil: Naviculaceae . In H. Ettl J. Gerloff H. Heynig , & D. Mollenhauer (Eds.), Süßwasserflora von Mitteleuropa 2/1 (p. 876 ). G. Fischer . Search in Google Scholar

Krammer, K., & Lange-Bertalot, H. (1988). Bacillariophyceae. 2. Teil: Bacillariaceae, Epithemiaceae, Surirellaceae. In H. Ettl, J. Gerloff, H. Heynig, & D. Mollenhauer (Eds.), Süßwasserflora von Mitteleuropa 2/2 (p. 596). G. Fischer. Krammer, K. , & Lange-Bertalot, H. ( 1988 ). Bacillariophyceae. 2. Teil: Bacillariaceae, Epithemiaceae, Surirellaceae . In H. Ettl J. Gerloff H. Heynig , & D. Mollenhauer (Eds.), Süßwasserflora von Mitteleuropa 2/2 (p. 596 ). G. Fischer . Search in Google Scholar

Krammer, K., & Lange-Bertalot, H. (1991a). Bacillariophyceae. 3. Teil: Centrales, Fragilariaceae, Eunotiaceae. In H. Ettl, J. Gerloff, H. Heynig, & D. Mollenhauer (Eds.), Süßwasserflora von Mitteleuropa 2/3 (p. 576). G. Fischer. Krammer, K. , & Lange-Bertalot, H. ( 1991a ). Bacillariophyceae. 3. Teil: Centrales, Fragilariaceae, Eunotiaceae . In H. Ettl J. Gerloff H. Heynig , & D. Mollenhauer (Eds.), Süßwasserflora von Mitteleuropa 2/3 (p. 576 ). G. Fischer . Search in Google Scholar

Krammer, K., & Lange-Bertalot, H. (1991b). Bacillariophyceae. 4. Teil: Achnanthaceae. Kritische Ergänzungen zu Navicula (Lineolatae) und Gomphonema. Gesamtliteraturverzeichnis. Teil 1-4. In H. Ettl, G. Gärtner, J. Gerloff, H. Heynig, & D. Mollenhauer (Eds.), Süßwasserflora von Mitteleuropa 2/4 (p. 437). Fischer. Krammer, K. , & Lange-Bertalot, H. ( 1991b ). Bacillariophyceae. 4. Teil: Achnanthaceae. Kritische Ergänzungen zu Navicula (Lineolatae) und Gomphonema. Gesamtliteraturverzeichnis. Teil 1-4 . In H. Ettl G. Gärtner J. Gerloff H. Heynig , & D. Mollenhauer (Eds.), Süßwasserflora von Mitteleuropa 2/4 (p. 437 ). Fischer . Search in Google Scholar

Kravtsov, V. A., Kravchina, M. D., Pankratova, N. A., & Kuleshov, A. F. (2002). The recent sedimentation processes in the Curonian and Vistula Lagoons. In E. M. Emelyanov (Ed.), Geology of the Gdańsk Basin, Baltic Sea (pp. 352–367). Yantarny Skaz. Kravtsov, V. A. Kravchina, M. D. Pankratova, N. A. , & Kuleshov, A. F. ( 2002 ). The recent sedimentation processes in the Curonian and Vistula Lagoons . In E. M. Emelyanov (Ed.), Geology of the Gdańsk Basin, Baltic Sea (pp. 352 367 ). Yantarny Skaz . Search in Google Scholar

Kruk-Dowgiałło L., Brzeska P., Błeńska M., Opioła R., Kuliński M. & Osowiecki A. 2009. Czy ochrona brzegów niszczy siedliska denne ? Studium przypadku-progi podwodne w Gdyni Orłowie. W: Polska Inżynieria Środowiska pięć lat po wstąpieniu do Unii Europejskiej. Monografie PAN. Lublin: 60 (3): 125–136. (In Polish). Kruk-Dowgiałło L. Brzeska P. Błeńska M. Opioła R. Kuliński M. & Osowiecki A. 2009 . Czy ochrona brzegów niszczy siedliska denne ? Studium przypadku-progi podwodne w Gdyni Orłowie. W: Polska Inżynieria Środowiska pięć lat po wstąpieniu do Unii Europejskiej . Monografie PAN. Lublin: 60 ( 3 ): 125 136 . (In Polish). Search in Google Scholar

Kruk-Dowgiałło, L., & Opioła, R. (2001). Makrofitobentos, Charakterystyka biologiczna. (w:) Warunki środowiskowe polskiej strefy południowego Bałtyku w 2000 roku. IMGW, Materiały Oddziału Morskiego. (In Polish) Kruk-Dowgiałło, L. , & Opioła, R. ( 2001 ). Makrofitobentos, Charakterystyka biologiczna. (w:) Warunki środowiskowe polskiej strefy południowego Bałtyku w 2000 roku . IMGW, Materiały Oddziału Morskiego . (In Polish) Search in Google Scholar

Kwiecień, K. (1990). Elementy klimatu (elements of the climate) In A. Majewski (Ed.), Zatoka Gdańska (Gulf of Gdańsk). Warszawa: IMGW, Wydawnictwo Geologiczne: 69-114. (In Polish). Kwiecień, K. ( 1990 ). Elementy klimatu (elements of the climate) In A. Majewski (Ed.), Zatoka Gdańska (Gulf of Gdańsk) . Warszawa : IMGW, Wydawnictwo Geologiczne : 69 - 114 . (In Polish). Search in Google Scholar

Lange-Bertalot, H. (2001). Navicula sensu stricto. 10 Genera Separated from Navicula sensu lato, Frustulia. In H. Lange-Bertalot (Ed.), Diatoms of Europe 2 (p. 526). A.R.G. Gantner Verlag K.G., Ruggell. Lange-Bertalot, H. ( 2001 ). Navicula sensu stricto. 10 Genera Separated from Navicula sensu lato, Frustulia . In H. Lange-Bertalot (Ed.), Diatoms of Europe 2 (p. 526 ). A.R.G. Gantner Verlag K.G., Ruggell . Search in Google Scholar

Leśniewska, M., & Witak, M. (2008). Holocene diatom biostratigraphy of the SW Gulf of Gdańsk, Southern Baltic Sea (part III). Oceanological and Hydrobiological Studies, 37(4), 35–52. https://doi.org/10.2478/v10009-008-0017-x Leśniewska, M. , & Witak, M. ( 2008 ). Holocene diatom biostratigraphy of the SW Gulf of Gdańsk, Southern Baltic Sea (part III) . Oceanological and Hydrobiological Studies , 37 ( 4 ), 35 52 . https://doi.org/10.2478/v10009-008-0017-x 10.2478/v10009-008-0017-x Search in Google Scholar

Leśniewska, M., & Witak, M. (2011). Diatoms as indicators of eutrophication in the western part of the Gulf of Gdańsk, Baltic Sea. Oceanological and Hydrobiological Studies, 40(1), 68–81. https://doi.org/10.2478/s13545-011-0008-5 Leśniewska, M. , & Witak, M. ( 2011 ). Diatoms as indicators of eutrophication in the western part of the Gulf of Gdańsk, Baltic Sea . Oceanological and Hydrobiological Studies , 40 ( 1 ), 68 81 . https://doi.org/10.2478/s13545-011-0008-5 10.2478/s13545-011-0008-5 Search in Google Scholar

Majewski, A. (1972). Charakterystyka hydrologiczna estuariowych wód u polskiego wybrzeża. Prace PIHM., 105, 3–40. Majewski, A. ( 1972 ). Charakterystyka hydrologiczna estuariowych wód u polskiego wybrzeża . Prace PIHM. , 105 , 3 40 . Search in Google Scholar

Majewski, A. (1990). Ogólna charakterystyka morfometryczna Zatoki Gdańskiej (General morphometric characteristics of the Gulf of Gdansk) In A. Majewski (Ed.), Zatoka Gdańska (Gulf of Gdańsk). (pp. 10 – 15). Warszawa: IMGW, Wyd. Geologiczne, (In Polish). Majewski, A. ( 1990 ). Ogólna charakterystyka morfometryczna Zatoki Gdańskiej (General morphometric characteristics of the Gulf of Gdansk) In A. Majewski (Ed.), Zatoka Gdańska (Gulf of Gdańsk) . (pp. 10 15 ). Warszawa : IMGW, Wyd. Geologiczne , (In Polish). Search in Google Scholar

Nowacki, J. (1993a). Termika, zasolenie i gestość wody (Thermal state, salinity and water density). In K. Korzeniewski (Ed.), Zatoka Pucka (The Puck Bay). (pp. 79–112). Fundacja Rozwoju Uniwersytetu Gdanskiego. (In Polish). Nowacki, J. ( 1993a ). Termika, zasolenie i gestość wody (Thermal state, salinity and water density) . In K. Korzeniewski (Ed.), Zatoka Pucka (The Puck Bay) . (pp. 79 112 ). Fundacja Rozwoju Uniwersytetu Gdanskiego . (In Polish). Search in Google Scholar

Nowacki, J. (1993b). Cyrkulacja i wymiana wód (Water circulation and exchange) In K. Korzeniewski (Ed.), Zatoka Pucka (The Puck Bay). (pp. 181–205). Fundacja Rozwoju Uniwersytetu Gdanskiego. (In Polish). Nowacki, J. ( 1993b ). Cyrkulacja i wymiana wód (Water circulation and exchange) In K. Korzeniewski (Ed.), Zatoka Pucka (The Puck Bay) . (pp. 181 205 ). Fundacja Rozwoju Uniwersytetu Gdanskiego . (In Polish). Search in Google Scholar

Pankow, H. (1990). Ostsee – Algenflora. Fischer. Pankow, H. ( 1990 ). Ostsee – Algenflora . Fischer . Search in Google Scholar

Pędziński, J., & Witak, M. (2019). Evidence of cultural eutrophication of the Gulf of Gdańsk based on diatom analysis. Oceanological and Hydrobiological Studies, 48(3), 247–261. https://doi.org/10.2478/ohs-2019-0022 Pędziński, J. , & Witak, M. ( 2019 ). Evidence of cultural eutrophication of the Gulf of Gdańsk based on diatom analysis . Oceanological and Hydrobiological Studies , 48 ( 3 ), 247 261 . https://doi.org/10.2478/ohs-2019-0022 10.2478/ohs-2019-0022 Search in Google Scholar

Pliński, M. (1987). Roślinność (Flora). In B. Augustowski (Ed.), Bałtyk Południowy (Southern Baltic) (pp. 321–346). Wydawnictwo PAN Wrocław. (In Polish) Pliński, M. ( 1987 ). Roślinność (Flora) . In B. Augustowski (Ed.), Bałtyk Południowy (Southern Baltic) (pp. 321 346 ). Wydawnictwo PAN Wrocław . (In Polish) Search in Google Scholar

Pliński, M. (1988). Glony Zatoki Gdańskiej. Część IV. Okrzemki, Gdańsk: Wydawnictwo UG.101 (In Polish). Pliński, M. ( 1988 ). Glony Zatoki Gdańskiej . Część IV . Okrzemki, Gdańsk : Wydawnictwo UG.101 (In Polish). Search in Google Scholar

Pliński, M. (1990). Important ecological features of the Polish coastal zone of the Baltic Sea. Limnologica, 20, 39–45. Pliński, M. ( 1990 ). Important ecological features of the Polish coastal zone of the Baltic Sea . Limnologica , 20 , 39 45 . Search in Google Scholar

Pliński, M. (1995). Phytoplankton of the Gulf of Gdańsk in 1992 and 1993. Oceanologia, 37, 123–135. Pliński, M. ( 1995 ). Phytoplankton of the Gulf of Gdańsk in 1992 and 1993 . Oceanologia , 37 , 123 135 . Search in Google Scholar

Pliński, M. & Florczyk, I. (1993). Makrofitobentos (Macrophytobenthos) In Korzeniewski K. (Ed.), Zatoka Pucka (Puck Bay) (pp. 416-421) Fundacja Rozwoju UG, Gdańsk (In Polish) Pliński, M. & Florczyk, I. ( 1993 ). Makrofitobentos (Macrophytobenthos) In Korzeniewski K. (Ed.), Zatoka Pucka (Puck Bay) (pp. 416 - 421 ) Fundacja Rozwoju UG, Gdańsk (In Polish) Search in Google Scholar

Pliński, M., & Kwiatkowski, J. (1996). Microphytobenthos of the shallow littoral of the southern Baltic. Oceanological Studies, 4, 65–77. Pliński, M. , & Kwiatkowski, J. ( 1996 ). Microphytobenthos of the shallow littoral of the southern Baltic . Oceanological Studies , 4 , 65 77 . Search in Google Scholar

Pliński, M., & Witkowski, A. (2009). Okrzemki – Bacillariophyta (Diatoms). In: Flora Zatoki Gdańskiej i wód przyległych (Bałtyk Południowy) Ed. M. Pliński. (223 pp.) Wyd. Naukowe Uniwersytetu Gdańskiego (In Polish) Pliński, M. , & Witkowski, A. ( 2009 ). Okrzemki – Bacillariophyta (Diatoms) . In: Flora Zatoki Gdańskiej i wód przyległych (Bałtyk Południowy) Ed. M. Pliński . ( 223 pp.) Wyd. Naukowe Uniwersytetu Gdańskiego (In Polish) Search in Google Scholar

Pliński, M., & Witkowski, A. (2011). Część druga: Okrzemki – Bacillariophyta (Diatoms). In: Flora Zatoki Gdańskiej i wód przyległych (Bałtyk Południowy) Ed. M. Pliński. (167 pp.) Wyd. Naukowe Uniwersytetu Gdańskiego (In Polish) Pliński, M. , & Witkowski, A. ( 2011 ). Część druga: Okrzemki – Bacillariophyta (Diatoms) . In: Flora Zatoki Gdańskiej i wód przyległych (Bałtyk Południowy) Ed. M. Pliński . ( 167 pp.) Wyd. Naukowe Uniwersytetu Gdańskiego (In Polish) Search in Google Scholar

Pliński, M., & Witkowski, A. (2013a). Część trzecia: Okrzemki – Bacillariophyta (Diatoms). In: Flora Zatoki Gdańskiej i wód przyległych (Bałtyk Południowy) Ed. M. Pliński. (250 pp.) Wyd. Naukowe Uniwersytetu Gdańskiego (In Polish). Pliński, M. , & Witkowski, A. ( 2013a ). Część trzecia: Okrzemki – Bacillariophyta (Diatoms) . In: Flora Zatoki Gdańskiej i wód przyległych (Bałtyk Południowy) Ed. M. Pliński . ( 250 pp.) Wyd. Naukowe Uniwersytetu Gdańskiego (In Polish). Search in Google Scholar

Pliński, M., & Witkowski, A. (2013b). Okrzemki – Bacillariophyta (Diatoms). Część czwarta: Okrzemki pierzaste (Thalassiophysales, Rhopalodiales, Bacillariales, Surirellales). In: Flora Zatoki Gdańskiej i wód przyległych (Bałtyk Południowy) Ed. M. Pliński. (153 pp.) Wyd. Naukowe Uniwersytetu Gdańskiego (In Polish) Pliński, M. , & Witkowski, A. ( 2013b ). Okrzemki – Bacillariophyta (Diatoms). Część czwarta: Okrzemki pierzaste (Thalassiophysales, Rhopalodiales, Bacillariales, Surirellales) . In: Flora Zatoki Gdańskiej i wód przyległych (Bałtyk Południowy) Ed. M. Pliński . ( 153 pp.) Wyd. Naukowe Uniwersytetu Gdańskiego (In Polish) Search in Google Scholar

Radke, B., Piketh, S., Wasik, A., Namieśnik, J., Dembska, G. & Bolałek, J. (2013). Aspects of pollution in Gdansk and gdynia Harbours at the coastal zone of the South Baltic Sea. TransNav - The International Journal on Marine Navigation and Safety of Sea Transportation 7(1): 11-17. https://doi.org/10.12716/1001.07.01.01. Radke, B. Piketh, S. Wasik, A. Namieśnik, J. Dembska, G. & Bolałek, J. ( 2013 ). Aspects of pollution in Gdansk and gdynia Harbours at the coastal zone of the South Baltic Sea . TransNav - The International Journal on Marine Navigation and Safety of Sea Transportation 7 ( 1 ): 11 - 17 . https://doi.org/10.12716/1001.07.01.01. 10.12716/1001.07.01.01 Search in Google Scholar

Ringer, Z. (1990). Roślinność. In A. Majewski (Ed.), Zatoka Gdańska (pp. 361–373). Wydawnictwa Geologiczne. (in Polish) Ringer, Z. ( 1990 ). Roślinność . In A. Majewski (Ed.), Zatoka Gdańska (pp. 361 373 ). Wydawnictwa Geologiczne . (in Polish) Search in Google Scholar

Rumek, A. (1948). Lista gatunków fitoplanktonu powierzchniowego Zatoki Gdańskiej. [In Polish]. Biuletyn Morskiego Laboratorium Rybackiego, 4, 139–141. Rumek, A. ( 1948 ). Lista gatunków fitoplanktonu powierzchniowego Zatoki Gdańskiej. [In Polish] . Biuletyn Morskiego Laboratorium Rybackiego , 4 , 139 141 . Search in Google Scholar

Schrader, H. & Gersonde, R. (1978). Diatoms and silico agellates in the eight meters sections of the lower Pleistocene at Capo Rossello. Utrecht Micropaleontological Bullietin 17: 129–176. Schrader, H. & Gersonde, R. ( 1978 ). Diatoms and silico agellates in the eight meters sections of the lower Pleistocene at Capo Rossello . Utrecht Micropaleontological Bullietin 17 : 129 176 . Search in Google Scholar

Schulz, P. (1926). Die Kieselalgen der Danziger Bucht mit Einschluss derjenigen aus glazialen und postglazialen Sedimenten. Botanisches Archiv. 13: 149–327. Schulz, P. ( 1926 ). Die Kieselalgen der Danziger Bucht mit Einschluss derjenigen aus glazialen und postglazialen Sedimenten . Botanisches Archiv . 13 : 149 327 . Search in Google Scholar

Snoeijs, P. (1993). Intercalibration and distribution of diatom species in the Baltic Sea. The Baltic Marine Biologist Publication, I. 16a. Opulus Press. Snoeijs, P. ( 1993 ). Intercalibration and distribution of diatom species in the Baltic Sea . The Baltic Marine Biologist Publication, I. 16a . Opulus Press . Search in Google Scholar

Snoeijs, P., & Balashova, N. (1998). Intercalibration and distribution of diatom species in the Baltic Sea. The Baltic Marine Biologist Publication, I. 16e. Opulus Press. Snoeijs, P. , & Balashova, N. ( 1998 ). Intercalibration and distribution of diatom species in the Baltic Sea . The Baltic Marine Biologist Publication, I. 16e . Opulus Press . Search in Google Scholar

Snoeijs, P., & Potapova, M. (1995). Intercalibration and distribution of diatom species in the Baltic Sea. The Baltic Marine Biologist Publication, I. 16c. Opulus Press. Snoeijs, P. , & Potapova, M. ( 1995 ). Intercalibration and distribution of diatom species in the Baltic Sea . The Baltic Marine Biologist Publication, I. 16c . Opulus Press . Search in Google Scholar

Stachura, K., & Witkowski, A. (1997). Response of the Gulf of Gdańsk diatom flora to the sewage run-off from the Vistula river. Fragmenta Floristica et Geobotanica, 42, 517–545. Stachura, K. , & Witkowski, A. ( 1997 ). Response of the Gulf of Gdańsk diatom flora to the sewage run-off from the Vistula river . Fragmenta Floristica et Geobotanica , 42 , 517 545 . Search in Google Scholar

Urbański, J. Grusza, G. & Chlebus, N. (2007). Fizyczna typologia dna Zatoki Gdańskiej, Atlas Cyfrowy, Sprawozdanie merytoryczne z realizacji projektu badawczego nr 2 PO4E00629 (In Polish). Urbański, J. Grusza, G. & Chlebus, N. ( 2007 ). Fizyczna typologia dna Zatoki Gdańskiej, Atlas Cyfrowy, Sprawozdanie merytoryczne z realizacji projektu badawczego nr 2 PO4E00629 (In Polish). Search in Google Scholar

Wielgat-Rychert, M., Ameryk, A., Jarosiewicz, A., Kownacka, J., Rychert, K., Szymanek, L., Zalewski, M., Agatova, A., Lapina, N., & Torgunova, N. (2013). Impact of the inflow of Vistula river waters on the pelagic zone in the Gulf of Gdańsk**The study was supported by the Polish Ministry of Science and Higher Education as statutory activities of the Department of Fisheries Oceanography and Marine Ecology of the National Marine Fisheries Research Institute (project O-147) and statutory activities of the Department of Ecology of the Pomeranian University in Slupsk (project 11.6.13). This study was also supported by the Polish Ministry of Science and Higher Education project N N304 025334. Oceanologia, 55(4), 859–886. Wielgat-Rychert, M. Ameryk, A. Jarosiewicz, A. Kownacka, J. Rychert, K. Szymanek, L. Zalewski, M. Agatova, A. Lapina, N. , & Torgunova, N. ( 2013 ). Impact of the inflow of Vistula river waters on the pelagic zone in the Gulf of Gdańsk**The study was supported by the Polish Ministry of Science and Higher Education as statutory activities of the Department of Fisheries Oceanography and Marine Ecology of the National Marine Fisheries Research Institute (project O-147) and statutory activities of the Department of Ecology of the Pomeranian University in Slupsk (project 11.6.13). This study was also supported by the Polish Ministry of Science and Higher Education project N N304 025334 . Oceanologia , 55 ( 4 ), 859 886 . 10.5697/oc.55-4.859 Search in Google Scholar

Witak, M. (2000). A diatom record of Late Holocene environmental changes in the Gulf of Gdańsk. Oceanological Studies, 19(2), 57–74. Witak, M. ( 2000 ). A diatom record of Late Holocene environmental changes in the Gulf of Gdańsk . Oceanological Studies , 19 ( 2 ), 57 74 . Search in Google Scholar

Witak, M. (2002). Postglacial history of the development of the Puck Lagoon (The Gulf of Gdańsk, Baltic Sea) based on the diatom ora. In A. Witkowski (Ed.), Diatom Monographs 2 (pp. 173). Ruggell: A.R.G. Gantner Verlag K.G. Witak, M. ( 2002 ). Postglacial history of the development of the Puck Lagoon (The Gulf of Gdańsk, Baltic Sea) based on the diatom ora . In A. Witkowski (Ed.), Diatom Monographs 2 (pp. 173 ). Ruggell : A.R.G. Gantner Verlag K.G. Search in Google Scholar

Witak, M. (2010). Application of diatom biofacies in reconstructing the evolution of sedimentary basins. Records from the southern Baltic Sea differentiated by the extent of the Holocene marine transgressions and human impact. In A. Witkowski (Ed.), Diatom Monographs 12 (p. 295). A.R.G. Gantner Verlag K.G. Witak, M. ( 2010 ). Application of diatom biofacies in reconstructing the evolution of sedimentary basins. Records from the southern Baltic Sea differentiated by the extent of the Holocene marine transgressions and human impact . In A. Witkowski (Ed.), Diatom Monographs 12 (p. 295 ). A.R.G. Gantner Verlag K.G. Search in Google Scholar

Witak, M. (2013). A review of the diatom research of the Gulf of Gdańsk and Vistula Lagoon (southern Baltic Sea). Oceanological and Hydrobiological Studies, 42(3), 336–346. https://doi.org/10.2478/s13545-013-0091-x Witak, M. ( 2013 ). A review of the diatom research of the Gulf of Gdańsk and Vistula Lagoon (southern Baltic Sea) . Oceanological and Hydrobiological Studies , 42 ( 3 ), 336 346 . https://doi.org/10.2478/s13545-013-0091-x 10.2478/s13545-013-0091-x Search in Google Scholar

Witak, M., & Dunder, J. (2007). Holocene diatom biostratigraphy of the SW Gulf of Gdańsk, Southern Baltic Sea (part II). Oceanological and Hydrobiological Studies, 36(3), 3–20. https://doi.org/10.2478/v10009-007-0021-6 Witak, M. , & Dunder, J. ( 2007 ). Holocene diatom biostratigraphy of the SW Gulf of Gdańsk, Southern Baltic Sea (part II) . Oceanological and Hydrobiological Studies , 36 ( 3 ), 3 20 . https://doi.org/10.2478/v10009-007-0021-6 10.2478/v10009-007-0021-6 Search in Google Scholar

Witak, M., Dunder, J., & Leśniewska, M. (2011). Chaetoceros resting spores as indicators of Holocene paleoenvironmental changes of the Gulf of Gdańsk, southern Baltic Sea. Oceanological and Hydrobiological Studies, 40(4), 21–29. https://doi.org/10.2478/s13545-011-0037-0 Witak, M. Dunder, J. , & Leśniewska, M. ( 2011 ). Chaetoceros resting spores as indicators of Holocene paleoenvironmental changes of the Gulf of Gdańsk, southern Baltic Sea . Oceanological and Hydrobiological Studies , 40 ( 4 ), 21 29 . https://doi.org/10.2478/s13545-011-0037-0 10.2478/s13545-011-0037-0 Search in Google Scholar

Witak, M., & Jankowska, D. (2014). Ancylus Lake stage in the Gulf of Gdańsk (southern Baltic Sea) based on diatom taphocoenoses. Nova Hedwigia, 143, 449–467. Witak, M. , & Jankowska, D. ( 2014 ). Ancylus Lake stage in the Gulf of Gdańsk (southern Baltic Sea) based on diatom taphocoenoses . Nova Hedwigia , 143 , 449 467 . Search in Google Scholar

Witak, M., Jankowska, D., & Piekarek-Jankowska, H. (2006). Holocene diatom biostratigraphy of the SW Gulf of Gdańsk, Southern Baltic Sea (part I). Oceanological and Hydrobiological Studies, 35(4), 307–329. Witak, M. Jankowska, D. , & Piekarek-Jankowska, H. ( 2006 ). Holocene diatom biostratigraphy of the SW Gulf of Gdańsk, Southern Baltic Sea (part I) . Oceanological and Hydrobiological Studies , 35 ( 4 ), 307 329 . Search in Google Scholar

Witak, M., & Pędziński, J. (2018). The diatom record of progressive anthropopressure in the Gulf of Gdańsk and the Vistula Lagoon. Oceanological and Hydrobiological Studies, 47(2), 167–180. https://doi.org/10.1515/ohs-2018-0016 Witak, M. , & Pędziński, J. ( 2018 ). The diatom record of progressive anthropopressure in the Gulf of Gdańsk and the Vistula Lagoon . Oceanological and Hydrobiological Studies , 47 ( 2 ), 167 180 . https://doi.org/10.1515/ohs-2018-0016 10.1515/ohs-2018-0016 Search in Google Scholar

Witak, M., Pędziński, J., Oliwa, S., & Hetko, D. (2020). Biodiversity of benthic diatom flora in the coastal zone of the Puck Bay (southern Baltic Sea): A case study of Hel Peninsula. Oceanological and Hydrobiological Studies, 49(3), 304–318. https://doi.org/10.1515/ohs-2020-0027 Witak, M. Pędziński, J. Oliwa, S. , & Hetko, D. ( 2020 ). Biodiversity of benthic diatom flora in the coastal zone of the Puck Bay (southern Baltic Sea): A case study of Hel Peninsula . Oceanological and Hydrobiological Studies , 49 ( 3 ), 304 318 . https://doi.org/10.1515/ohs-2020-0027 10.1515/ohs-2020-0027 Search in Google Scholar

Witkowski, A. (1994). Species composition and ecology of the Puck Bay (southern Baltic Sea) coastal shallow microbial mat. Zeszyty Naukowe UG Oceanografia, 13, 85–99. Witkowski, A. ( 1994 ). Species composition and ecology of the Puck Bay (southern Baltic Sea) coastal shallow microbial mat . Zeszyty Naukowe UG Oceanografia , 13 , 85 99 . Search in Google Scholar

Witkowski, A., Lange-Bertalot, H. & Metzeltin, D. (2000). Diatom ora of marine costs I. Iconographica Diatomologica 7 (pp. 925). ARG Gantver Verlag KG Witkowski, A. Lange-Bertalot, H. & Metzeltin, D. ( 2000 ). Diatom ora of marine costs I . Iconographica Diatomologica 7 (pp. 925 ). ARG Gantver Verlag KG Search in Google Scholar

Witkowski, A., & Miller, U. (1999). Diatom flora of the Mastogloia Sea – a key to present and future environmental changes in the Baltic Sea. Quaternaria, 7, 87–100. Witkowski, A. , & Miller, U. ( 1999 ). Diatom flora of the Mastogloia Sea – a key to present and future environmental changes in the Baltic Sea . Quaternaria , 7 , 87 100 . Search in Google Scholar

Witkowski, A., & Pempkowiak, J. (1995). Reconstructing the development of human impact from diatoms and Pb210 sediment dating (the Gulf of Gdansk – southern Baltic Sea). Geographia Polonica, 65, 63–77. Witkowski, A. , & Pempkowiak, J. ( 1995 ). Reconstructing the development of human impact from diatoms and Pb210 sediment dating (the Gulf of Gdansk – southern Baltic Sea) . Geographia Polonica , 65 , 63 77 . Search in Google Scholar

You, Q., Liu, Y., Wang, Y., & Wang, Q. (2009). Taxonomy and distribution of diatoms in the genera Epithemia and Rhopalodia from the Xinjiang Uygur Autonomous Region, China. -. Nova Hedwigia, 89, 397–430. https://doi.org/10.1127/0029-5035/2009/0089-0397 You, Q. Liu, Y. Wang, Y. , & Wang, Q. ( 2009 ). Taxonomy and distribution of diatoms in the genera Epithemia and Rhopalodia from the Xinjiang Uygur Autonomous Region, China. - . Nova Hedwigia , 89 , 397 430 . https://doi.org/10.1127/0029-5035/2009/0089-0397 10.1127/0029-5035/2009/0089-0397 Search in Google Scholar

Zgrundo, A., & Bogaczewicz-Adamczak, B. (2004). Applicability of diatom indices for monitoring water quality in coastal streams in the Gulf of Gdansk Region, northern Poland. Oceanological and Hydrobiological Studies, 33(3), 31–46. Zgrundo, A. , & Bogaczewicz-Adamczak, B. ( 2004 ). Applicability of diatom indices for monitoring water quality in coastal streams in the Gulf of Gdansk Region, northern Poland . Oceanological and Hydrobiological Studies , 33 ( 3 ), 31 46 . Search in Google Scholar

Recommended articles from Trend MD

Plan your remote conference with Sciendo