https://czasopisma.bg.ug.edu.pl/index.php/oandhs/issue/feedOceanological and Hydrobiological Studies2024-02-21T10:39:14+00:00Anna Dziubińskaohs@ug.edu.plOpen Journal Systems<p style="text-align: justify;">The objective of Oceanological and Hydrobiological Studies, an international journal published by the University of Gdańsk in cooperation with the Academic Publishing Company Walter DeGruyter, is to provide the most comprehensive and reliable source of information on the current knowledge in the fields of science related to both oceanology and hydrobiology. The main emphasis is on publishing high quality articles, easily available to scientists from all over the world. As an editorial team, we are convinced that Oceanological and Hydrobiological Studies will continue to grow as a journal meant for scientists and researchers who wish to keep abreast of the latest developments in these fields of science.</p>https://czasopisma.bg.ug.edu.pl/index.php/oandhs/article/view/10375An ichthyofaunal amendment with the length-weight relations and condition factors of some endemic and invasive freshwater fishes from Western Anatolia2024-02-07T09:13:22+00:00Irmak KurtulCüneyt KayaArda ŞenCeylin ÖzcanDeniz ErcivanKaan DemiralMelike GüngörAli İlhanHasan Musa Sarı<p>In the scope of this study, fish fauna of Küçük Menderes River and its tributaries, updated with the comparison of the recent ichthyofaunal studies, as well as the length-weight relations (LWR) and condition factors (CF) were estimated for 7 freshwater fish species belonging to six families from the river basin: endemic <em>Oxynoemacheilus eliasi</em>, <em>Cobitis fahireae</em>; invasive, <em>Carassius gibelio</em>, <em>Atherina boyeri</em>, transloce <em>Perca fluviatilis</em> and the native <em>Squalius fellowesii</em>, <em>Cyprinus carpio</em>. The fish samples were collected with various fishnets and DC electro-fishing devices from six stations in 2018 and 2019. The LWR of the fishes was studied based on 379 specimens. The estimated values of parameter b ranged from 2.884 (<em>A. boyeri</em>) to 3.176 (<em>C. fahireae</em>). The coefficient of determination (R2) was changed between 0.792 to 0.980 for all sampling localities. In the study, Fulton’s condition factor ranged between 0.391 (<em>S. fellowesii</em>) to 3.080 (<em>S. fellowesii</em>); the relative condition factor ranged between 0.346 (<em>O. eliasi</em>) to 2.746 (<em>S. fellowesii</em>), respectively. This research is anticipated to contribute valuable insights for the conservation of the species, while also furnishing essential data to inform future fisheries management studies in the region.</p>2023-12-31T00:00:00+00:00Copyright (c) 2024 https://czasopisma.bg.ug.edu.pl/index.php/oandhs/article/view/10376Annual, seasonal and spatial differences in the growth rate of Baltic cod larvae and early juveniles in relation to zooplankton biomass fluctuations in 2006-20142024-02-07T11:15:05+00:00Katarzyna SpichDariusz Piotr Fey<p>It is an acknowledged theory that a faster growth rate, determined by various environmental drivers, may boost the survival of larval and juvenile fish. In this study we examined the differences in the growth rate of larval and juvenile cod (age 2 – 136 d; SL: 4.1 – 39.2 mm) between the years 2006 and 2014, sub-areas of the Baltic Sea (Bornholm Basin, BB; Słupsk Furrow, SF; Gdańsk Basin, GB), and seasons (spring and summer). The average growth rate for all specimens was 0.25 mm/d, with significantly lower values between 2012 and 2014 than between 2006 and 2011. A reduction in zooplankton biomass, especially the large zooplankton fraction, was observed after the 2006–2008 period, which was related to the prevailing temperature conditions in the surface layers. The reduction in zooplankton biomass was accompanied by changes in the structure of zooplankton: less <em>T. longicornis, C. hamatus, and Pseudocalanus spp</em>., and more <em>Acartia spp</em>. The results suggest that the inter-annual differences observed in zooplankton biomass and structure are likely responsible for the observed reduction in the growth rate of cod larvae between 2012 and 2014 compared to the years between 2006 and 2011. The growth rate reduction could be one of the reasons for the decline in the recruitment of eastern Baltic cod between the years 2013 and 2015, after the high recruitment years of the period 2011-2012.</p>2023-12-31T00:00:00+00:00Copyright (c) 2024 https://czasopisma.bg.ug.edu.pl/index.php/oandhs/article/view/10377Morphological comparison for the dorsal fin of Chrysichthys auratus, Synodontis schall, and Synodontis serratus (Teleosti: Siluriformes) collected from the Lake Nasser and the River Nile, Egypt2024-02-07T11:50:54+00:00Mahmoud M. S. FarragLaith A. JawadJoo M. Park<p>The anatomy, growth, and differentiation of the dorsal fin spines of three catfish species collected from the Nile River and Lake Nasser. Egyptian waters are described, and terminology is suggested for their parts. Features of the dorsal fin spine that change with growth are also described. The results showed that in all species studied, the dorsal spine is an elongate, compressed, tapered, slightly arched, osseous structure, bearing a series of retrorse dentations along the anterior and posterior surfaces and has a sharp sagittate tip. The retrorse, anterior dentations are most pronounced in the upper third of the spine and gradually alter in form until they appear as a series of distinct notches on the basal third of the spine. The anterolateral surfaces of the dorsal spine are marked by numerous short, irregular, shallow, anastomosing, longitudinal furrows. In three species (<em>C. auratus, S. schall, S. serratus</em>), the posterior process is poorly developed and directed laterally in young individuals and well produced and directed posteriorly in older specimens. In <em>S. schall</em> and <em>S. serratus</em>, the posterior blocking process of the large specimens has a wavy edge, while in <em>S. serratus</em>, it is curved in young individuals and straight in larger specimens.</p>2023-12-31T00:00:00+00:00Copyright (c) 2024 https://czasopisma.bg.ug.edu.pl/index.php/oandhs/article/view/10379Differences of water chemistry, bird assemblages and nutrient loads introduced by waterbirds into morphologically similar waterbodies2024-02-09T08:23:55+00:00Robert GwiazdaJoanna Kosiba<p>The number and structure of waterbirds is affected by the size of the waterbody, the presence of islands and macrophytes, but also by their trophy status. The aims of the study were to compare nutrients in water, numbers of waterbird assemblages, and the loading of nitrogen and phosphorus introduced by waterbirds in two similar waterbodies with different rates of water discharge. This study was conducted in two eutrophic shallow waterbodies, P1 and P2 in 2016 and 2017. The median concentrations of NO2 - , NO3 - and NH4 + were 4.0 times, 3.2 times, and 1.7 times greater in the P1 than in the P2 location, respectively. Similar proportions of organic matter in sediments were statistically greater in P1. The number of birds was also significantly greater in P1 than in P2. The waterbirds (<em>Anas platyrhynchos, Aythya fuligula, Fulica atra, Phalacrocorax carbo and Chroicocephalus ridibundus</em>) excreted 5.2 times more total phosphorous and 3.3 times more total nitrogen in P1 than in P2. Significant negative correlations were also found between the concentrations of NO3 - and the number of waterbirds in P1.</p>2023-12-31T00:00:00+00:00Copyright (c) 2024 https://czasopisma.bg.ug.edu.pl/index.php/oandhs/article/view/10380Utilizing fluctuation asymmetry to assess the effects of U-238 radioactivity on the marine ecosystem around the Madras nuclear power plant, India2024-02-09T10:29:32+00:00Sherif A. AL-SharifManjulatha ChaparaAtef El-TaherAhmed Salah-Tantawy<p>The monitoring of marine ecosystems is crucial due to the growing threat posed by nuclear power plants and other nuclear anthropogenic emissions. In our work, we used a straightforward and low-cost biomonitoring technique called fluctuation asymmetry (FA) to examine the variation between the left and right sides (developmental instability) of organisms’ traits that were influenced by genetic and environmental variables in the early stages of ontogenesis. The specimens of fish (<em>Leiognathus sp.</em>) and crabs (<em>Portunus sanguinolentus</em>) were collected seasonally and used as bioindicators to determine the effects of Uranium-238 (U-238) radioactivity around a nuclear power plant. The obtained results revealed that FA values were not considered typical values (FA = 0) in all seasons. Moreover, FA values of <em>Leiognathus sp</em>. exhibited insignificant fluctuation for a particular characteristic through the different seasons, while a significant fluctuation occurred amongst the characteristics themselves throughout the same season. Inversely, FA values of the four characteristics in <em>Portunus sanguinolentus</em> displayed seasonal variation amongst them all. Statistically, there was a strong positive correlation (r = 0.5, p < 0.05) between U-238 radioactivity in the flesh of both organisms and the fluctuation asymmetry of different traits but it is not a sign that any radioactive pollution exists.</p>2023-12-31T00:00:00+00:00Copyright (c) 2024 https://czasopisma.bg.ug.edu.pl/index.php/oandhs/article/view/10437Defense responses of the green microalgae Chlorella vulgaris to the vanadium pentoxide nanoparticles2024-02-20T11:49:13+00:00Hanifeh Akbarian KalehjahiMorteza Kosari-NasabMojtaba AminiAli Movafeghi<p>Although vanadium-based nanomaterials have found extensive use in industry, their influence on ecosystems and living organisms is not yet well investigated. In this study, hydrothermal methods were utilized for the synthesis of vanadium pentoxide nanoparticles (V2 O5 NPs). The gained NPs were characterized using XRD, FT-IR, EDS, DLS, SEM and TEM techniques. Subsequently, the toxic effects of V2 O5 NPs on the model green microalgae <em>Chlorella vulgaris</em> were evaluated. According to the obtained results, V2 O5 NPs caused a significant reduction in cell number and biomass production of algae in a dose and time dependent manner. Moreover, flow cytometric analysis confirmed a reduction in the quantity of living cells. Scanning electron microscopy showed plasmolysis and deformation of the cells after exposure to nanoparticles. The photosynthetic pigments and phenolics content exhibited a decrease in comparison with the control sample. Although, non-enzymatic antioxidant system in C. vulgaris displayed an average action, antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) showed a dose dependent increasing trend. These intercellular reactions designated the activation of the antioxidant defense system in response to the induced oxidative stress by V2 O5 NPs.</p>2023-12-31T00:00:00+00:00Copyright (c) 2024 https://czasopisma.bg.ug.edu.pl/index.php/oandhs/article/view/10438Metal pollution status and health risk assessment of beach sediments along the Mersin coast, Turkey2024-02-21T07:24:50+00:00Özgür Özbayİsmail Akçay<p>In the present study, the ecological risk assessment of metal contamination in beach sediments along the Mersin coast was determined using the metal contents of beach sediments in Mersin, Kızkalesi, Susanoğlu and Taşucu region obtained between 2006 and 2009. Furthermore, the potential health risk assessment for ingestion and dermal contact pathways of adults and children was determined. Ecological risk assessment of heavy metals showed that there is no pollution in the beach sediments for the metals Cu, Pb and Zn for the all studied coasts. However, the high ecological risk indices calculated in this study strongly suggested an apparent Cd, Cr and Ni pollution in the studied beach sediments due to natural and anthropogenic contamination. Study findings indicated the HI values were greater than 1 for the metal Cr. The TCR values were higher than 1.00E-04 for the metals Cr and Ni calculated for adults, and for the metal Cu, Cr and Ni calculated for children, respectively. All these findings showed that there is a high carcinogenic risk for adults and children resident in the Mersin province from carcinogenic Cr and Ni whilst the studied coasts have additional health risks to children from carcinogenic Cu.</p>2023-12-31T00:00:00+00:00Copyright (c) 2024 https://czasopisma.bg.ug.edu.pl/index.php/oandhs/article/view/10439Antioxidant radical scavenging capacity and total carotenoid content of narrow-clawed crayfish (Pontastacus leptodactylus, Eschscholtz, 1823) in Atikhisar Reservoir (Çanakkale, Türkiye)2024-02-21T07:35:53+00:00Sefa AcarlıBayram KızılkayaPervin VuralSelçuk BerberSemih KaleDeniz Acarlı<p>In this study, antioxidant radical scavenging capacity and total carotenoid content in the meat and shells of <em>Pontastacus leptodactylus</em> were investigated. Concerning the antioxidant scavenging effect, the highest IC50 values were found to be 388.77 mg g-1 and 155.53 mg g-1 for females and males in July and March, respectively. The mean IC50 values of the meat were calculated as 239.83 mg g-1 and 105.21 mg g-1 for females and males, respectively. The mean total carotenoid content in the meat was found to be 14.35 and 12.78 µg g-1 for females and males, respectively. The results indicated that crayfish meat had antioxidant radical scavenging capacity and was rich in carotenoid content.</p>2023-12-31T00:00:00+00:00Copyright (c) 2024 https://czasopisma.bg.ug.edu.pl/index.php/oandhs/article/view/10440A biomonitoring study of Diadema setosum: metal bioaccumulation and current status in Iskenderun Bay, eastern Mediterranean2024-02-21T08:19:11+00:00Erkan Uğurlu<p>Concentrations of aluminum, chromium, cobalt, nickel, cadmium, lead, manganese, iron and zinc were determined in sea urchin species, <em>Diadema setosum</em> from Iskenderun Bay in December 2022. The level of metals was determined by Inductively Coupled Plasma-Mass Spectrometer (ICP-MS). Concentrations of the heavy metals in the examined sea urchins ranged as follows: Al 0.07-7.17 µg g-1; Cr 0.07–0.8 µg g-1; Co 0.01–0.2 µg g-1; Ni 0.2–2.9 µg g-1; Cd 0.0–0.02 µg g-1; Pb 0.4-3.5 µg g-1; Mn 0.03–0.4 µg g-1; Fe 1.2-57.2 µg g-1; Zn 0.28–2.7 µg g-1, respectively. The highest accumulation of Fe and Pb metals was determined in the tissues of the sea urchin. The present study suggests that <em>D. setosum</em> could be a potential biological indicator of metal pollution in the İskenderun Bay. Furthermore, soft tissues generally had lower levels overall. For this reason, the data show that <em>D. setosum</em> is a very good heavy metal collector and therefore may be used successfully to monitor heavy metal levels in Iskenderun Bay.</p>2023-12-31T00:00:00+00:00Copyright (c) 2024 https://czasopisma.bg.ug.edu.pl/index.php/oandhs/article/view/10441Species diversity, abundance, and distribution of freshwater prawns along a selected perennial stream in Ngangla Gewog, Zhemgang, Southern Bhutan2024-02-21T09:06:21+00:00Thinley WangdaSabreen BashirBhagat SuberiAgrataben VadhelTabarak MalikAnand Mohan<p>The study and diversity of freshwater prawns are of great importance due to growing interest in biodiversity and its relative abundance. The present study was carried out for a selected stream divided into three different habitat types: namely, pond, run, and riffle. The study was focused on the diversity and abundance of prawns. To make it more systematic, a transect was laid upon the stream and it was divided into 30 plots with 100 m intervals. <em>Metapenaeus rosenbergii</em>, <em>Penaeus japonicas</em>, and <em>Metapenaeus insolitus</em> were species recorded in the pond habitat type only. The Penaeus genus was the most prominent in the study area while the genus <em>Metapenaues</em> was the least abundant. The diversity of freshwater prawns was found to be highest in the pond rather than the run and riffle. Documented information for prawn populations in Bhutan is sparse. Therefore, there is a wide research gap regarding prawn diversity in Bhutan. This study will help to establish a baseline data for the prawn distribution in the proposed study area. The present study will serve as a reference guide for future researchers.</p>2023-12-31T00:00:00+00:00Copyright (c) 2024 https://czasopisma.bg.ug.edu.pl/index.php/oandhs/article/view/10442Estimation of zooplankton density with artificial neural networks (a new statistical approach) method, Elazığ-Türkiye2024-02-21T10:39:14+00:00Hilal Bulut<p>This study was carried out to predict the zooplankton density in the Cip reservoir (Elazığ) with an artificial neural network, using some water quality parameters. The plankton samples were collected monthly from Cip Reservoir in 2021- 2022, using a standard plankton net from three stations. Water temperature, dissolved oxygen, pH, electrical conductivity, secchi disk, alkalinity, total nitrogen and total phosphorus were measured. The actual values of zooplankton density and results obtained from the artificial neural networks were compared. Mean absolute percent error (MAPE) values were calculated with actual values and ANNs values. ANNs values were determined to be close to the real data. MAPE percentage value at the first station was determined as 1.143 for Rotifer, 0.118 for Cladocera, and 0.141 for Copepoda. The MAPE percentage value at the second station was determined as 0.941 for Rotifer, 0.377 for Cladocera, and 0.185 for Copepoda. The MAPE percentage value at the third station was determined as 0.342 for Rotifer, 0.557 for Cladocera, and 0.301 for Copepoda. In the present study, it has been seen that artificial neural networks with a learning feature are successful in predicting zooplankton densities in an aquatic environment. It can be concluded from the study that ANNs are a powerful tool for understanding their relationships with the environment.</p>2023-12-31T00:00:00+00:00Copyright (c) 2024