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Volume 51 (2022): Edition 2 (June 2022)

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Détails du magazine
Format
Magazine
eISSN
1897-3191
Première publication
23 Feb 2007
Période de publication
4 fois par an
Langues
Anglais

Chercher

Volume 51 (2022): Edition 2 (June 2022)

Détails du magazine
Format
Magazine
eISSN
1897-3191
Première publication
23 Feb 2007
Période de publication
4 fois par an
Langues
Anglais

Chercher

10 Articles
Accès libre

Pre-probiotic effects of different bacterial species in aquaculture: behavioral, hematological and oxidative stress responses

Publié en ligne: 07 Jul 2022
Pages: 133 - 142

Résumé

Abstract

There is very limited aquaculture research on candidate probiotics and their effects on fish physiology. In this study, acute applications of four different molecularly identified bacterial species – Brevibacillus brevis FD-1 (A), Pseudomonas fluorescens FDG-37 (B), Bacillus sphaericus FD-48 (C), and B. amyloliquefaciens TV-17C (D), with potential in aquaculture, were tested in rainbow trout (Oncorhynchus mykiss) under static conditions. Physiological changes in blood tissue [hematological indices: erythrocyte count (RBC), leukocyte count (WBC), hemoglobin (Hb), hematocrit (Hct), platelet count (PLT), mean cell hemoglobin concentration (MCHC), mean cell hemoglobin (MCH), and mean cell volume (MCV)], oxidative stress responses in liver and gill tissues [malondialdehyde (MDA) level, antioxidant enzyme activities: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathione reductase (GR), glutathione-S-transferase (GST), glucose-6-phosphate dehydrogenase (G6PD)] and acetylcholinesterase (AChE) activity in brain tissue (as neurotoxic biomarker) were investigated. Additionally, behavioral differences were recorded by measuring swimming performance to support neurotoxic findings in all treatment groups. The LC5024 value of FDG-37 strain was determined through analysis as 1.0 × 108 CFU ml-1. Inhibition of enzyme activity, increase in the MDA level, as well as significant differences in hematological indices and swimming performance were determined in rainbow trout treated with B compared to control and other bacterial groups in gills. The potential for using group FD-48 and TV-17C bacterial strains as probiotics in aquaculture is more pertinent when considering the research findings and water quality parameters.

Key words

  • fisheries
  • ecosystem management
  • probiotic
  • oxidative stress
  • LC
Accès libre

First record of the common sun star Crossaster papposus (L., 1767) in the Baltic Sea in over 100 years

Publié en ligne: 07 Jul 2022
Pages: 143 - 148

Résumé

Abstract

The rare in the German North and Baltic Sea waters and strictly protected sea star Crossaster papposus was found in 2019 and 2021 during monitoring activities in a marine protected area. This unique observation was achieved by using towed camera platform imagery along a transect in the Fehmarn Belt, which allows monitoring of a much larger area of the seafloor compared to traditional invasive grab and dredge sampling. The last time C. papposus was documented in this area was in 1871, indicating the rarity of this species in the Baltic Sea. Possible explanations for such rare records of the occurrence of this presumably native species in the study region are briefly discussed, including uncommon survival due to salinity conditions caused by prior inflows of saline water from the North Sea.

Key words

  • Fehmarn Belt
  • protected species
  • monitoring data
  • underwater imaging approach
Accès libre

Heavy metal content in coral reef-associated fish collected from the central Red Sea, Saudi Arabia

Publié en ligne: 07 Jul 2022
Pages: 149 - 157

Résumé

Abstract

The concentration of heavy metals in marine fish is important for assessing the health risks associated with fish consumption. In this study, the concentration of metals such as copper, lead and manganese were analyzed in the muscle tissue of five coral reef-associated fish species collected from the central Red Sea, Saudi Arabia. The maximum copper content of 0.183 μg g-1 (ww) was detected in fish samples. Fish samples also showed maximum lead and manganese values of 0.030 and 0.064 μg g-1 (ww), respectively. The metal concentration in fish tissue samples did not vary significantly between the fish species. In conclusion, the results obtained indicate that the content of heavy metals in the coral reef-associated fishes is below the values determined by various agencies for seafood safety.

Key words

  • seafood
  • marine fish
  • marine pollution
  • bioaccumulation
  • metal pollution index
Accès libre

Effects of diet quantity on growth performance of juvenile sea cucumbers Holothuria scabra

Publié en ligne: 07 Jul 2022
Pages: 158 - 166

Résumé

Abstract

Sea cucumbers are in high demand in the world market due to their nutritional and medicinal values. In this study, the growth performance of juvenile sea cucumbers Holothuria scabra fed with different proportions of two feeds was analyzed. Commercially available sea cucumber feed (feed-A) and formulated feed (feed-B) were used for the experiments. Animals fed with 2% feed-A showed a negative growth rate. Maximum growth was observed in animals fed with 8% feed-A and feed-B. While feed-A treated groups showed significant variation (P < 0.05) in growth performance between different percentages of diets, feed-B treated animals showed no such variation. Feed-B treated animals showed higher growth rates compared to feed-A treated sea cucumbers. Water quality parameters and anoxic conditions of the soil in culture tanks did not change due to the higher percentage of feeds. In conclusion, this study showed that diet percentage is an important factor for the optimum growth of sea cucumbers.

Key words

  • aquaculture
  • invertebrate culture
  • echinoderms
  • feed formulation
  • sandfish
  • Red Sea
Accès libre

Assessment of 8-hydroxy-2-deoxyguanosine activity, apoptosis, acetylcholinesterase and antioxidant enzyme activity in Capoeta umbla brain exposed to chlorpyrifos

Publié en ligne: 07 Jul 2022
Pages: 167 - 177

Résumé

Abstract

In this study, neurotoxic responses to exposure to chlorpyrifos (CPF) at different doses (55 and 110 μg l-1) and at different time intervals (24 and 96 h) were investigated in Siraz fish (Capoeta umbla) using 8-hydroxy 2-deoxyguanosine (8-OHdG) activity, caspase-3, acetylcholinesterase (AChE) and oxidative stress parameters [malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GR)]. In this study, the LC50 value of CPF was determined for the first time for C. umbla and calculated as 440 μg l-1. In this study, 12.5% (55 μg l-1) and 25% (110 μg l-1) of the LC50 value were used. The obtained data indicate a significant increase in the MDA level and inhibition of antioxidant enzymes in the brain (p < 0.05). Considering DNA damage and the apoptotic process, no significant changes were found in 8-OHdG and caspase-3 activity at both doses exposed for 24 h, but a significant increase was detected in both markers at 96 hours compared to the control group (p < 0.05). In the case of AChE activity, which is one of the neurotoxic markers in the brain, while inhibition was determined only at the high concentration (110 μg l-1) at the end of 24 hours, a decrease in enzyme activity was observed at the end of 96 hours in both concentration groups. In the light of all these results, we can say that CPF showed inhibitory effects on enzyme activity and inducing effects on MDA, caspase-3 and 8-OHdG levels. Based on these results, it can be concluded that CPF contributes to oxidative stress in fish and may have neurotoxic effects.

Key words

  • fish
  • brain
  • neurotoxicity
  • pesticides
  • apoptosis
  • toxicity mechanism
Accès libre

Intercellular and extracellular amino acids of different bloom species in the Mediterranean Sea

Publié en ligne: 07 Jul 2022
Pages: 178 - 188

Résumé

Abstract

The presented laboratory experiment was designed to characterize the quantity and compositional variation of algal extracellular amino acids (AAs) that may represent an alternative nutrient source in a natural environment. To resemble algal bloom scenarios, analyses were conducted in mono- and/or co-cultures of the bloom-forming species Skeletonema costatum, Scrippsiella trochoidea, Ulva fasciata, and Corallina officinalis during their active growth phase. The study revealed that S. costatum exhibited higher production of the dominant AAs than S. trochoidea. Alanine, lysine, and threonine acids are the dominant amino acids in S. costatum and S. trochoidea filtrates, which may play a role in mucus formation during mucosal phytoplankton blooms with negative ecological effects. On the other hand, aspartic, glutamine, alanine, and leucine acids are the dominant amino acids in macroalgae. In co-culture experiments, U. fasciata shows strong and rapid allelopathic activity against these two potentially harmful species. The AA production offers an advantage to species with the capacity to absorb them to form blooms. Thus, anthropogenic inorganic nutrient inputs may be less important for the development of algal blooms in coastal waters. A major difference that distinguishes this work from others is the use of specific multi-taxa cultures of phytoplankton and macroalgae. The study represents a new research effort in Alexandria waters.

Key words

  • Extracellular amino acids
Accès libre

Effects of anthropogenic activities on nutrient parameters in the North Eastern Mediterranean Sea (Bay of Sığacık/Aegean Sea)

Publié en ligne: 07 Jul 2022
Pages: 189 - 202

Résumé

Abstract

This study aims to examine the physicochemical parameters of seawater (temperature, pH, salinity, dissolved oxygen, suspended particulate matter, ammonium-nitrogen, nitrite-nitrogen, nitrate-nitrogen, and phosphate-phosphorus, burnable organic matter in the sediment), and possible effects of pollution in Sığacık Bay where different anthropogenic activities are carried out. Samples of surface seawater (0 m), bottom seawater (2 m), and sediment were collected monthly from four sampling sites between September 2013 and September 2014. Annual mean nutrient values were determined as 1.6 ± 0.14 μg.at.NH4+-N l-1, 0.1 ± 0.01 μg.at.NO2--N l-1, 0.8 ± 0.08 μg.at.NO3--N l-1, 0.7 ± 0.08 μg.at.PO43--P l-1, SPM 21.4 ± 0.33 mg l-1. The BOM content in the sediment was 5.6 ± 0.39%. As a result of the study, it was determined that Sığacık Bay was polluted by anthropogenic point and non-point source pollution. According to the water quality criteria, the bay was found to be in the group of polluted seawater in terms of phosphate phosphorus.

Key words

  • water quality
  • nitrogen
  • phosphorus
  • sediment
  • PCA
  • Aegean Sea
Accès libre

Skeletal deformities in Barbus xanthos (Teleostei: Cyprinidae) collected from the Dalaman River in southwestern Turkey

Publié en ligne: 07 Jul 2022
Pages: 203 - 211

Résumé

Abstract

In this study, skeletal anomalies such as vertebral centra deformation, lordosis (ventral curvature), and consecutive repetition of lordosis and kyphosis were examined in specimens of Barbus xanthos (Güçlü, Kalaycı, Küçük & Turan, 2020) collected from the Dalaman River, southwestern Turkey. Abnormalities of the vertebral column were observed in both thoracic and caudal vertebrae. Cases of lordosis and consecutive repetition of lordosis and kyphosis showed varying degrees of severity. Specimens with consecutive repetition of lordosis showed the most acute deformities among the cases studied, as they revealed complicated incidences of skeletal anomalies. None of the cases were fatal as they occurred in adult individuals. This study discusses the possible causes of such deformities and the usefulness of this type of study in environmental monitoring.

Key words

  • vertebral deformity
  • lordosis
  • kyphosis
  • pollution
  • environment
Accès libre

Evaluation of ecological risk analysis for benthic macroinvertebrates in paddy fields in the Meriç–Ergene River Basin (Turkish Thrace)

Publié en ligne: 07 Jul 2022
Pages: 212 - 223

Résumé

Abstract

Benthic macroinvertebrates are very important components of aquatic environments, and monitoring their population dynamics helps us understand the effects of environmental factors on ecosystems. This study aimed to determine the dynamics of benthic macroinvertebrate fauna in paddy fields in the Meriç–Ergene River Basin (Turkish Thrace region) by investigating some physicochemical environmental parameters that may affect its distribution. For this purpose, water and sediment samples were collected from paddy fields in the study area during the cultivation season, including spring, summer and autumn of 2016, taking into account the water resources that supply the rice fields (artesian water, the Meriç River, the Ergene River and Meriç–Ergene mixed water). A total of 47 taxa (on average 8953 individuals per m2) were identified at the study sites. Water samples were analyzed to determine water temperature, pH, conductivity, salinity, total dissolved solids, calcium, magnesium, total hardness, nitrite nitrogen, nitrate nitrogen, phosphate, sulfate, dissolved oxygen and pesticides, and sediment samples were analyzed to determine the content of some heavy metals, including Cd, Ni, Cu, and Mn. The biological risk index (mERM-Q) and the potential ecological risk index (RI) were applied to the data and a hypothetical ecological risk analysis was conducted using our data and data available in the literature to assess the ecological risk profile of the ecosystem based on benthic macroinvertebrates. To this end, environmental factors were grouped based on the literature as heavy metals (S1), nutrients (S2), other physicochemical parameters (S3) and pesticides (S4), while organisms were grouped as Oligochaeta, Chironomidae, Insecta and others based on the dynamics of benthic macroinvertebrates to assess pressure factors. As a result, pesticides (S4) were found to exert the strongest ecological pressure on benthic macroinvertebrate fauna in paddy fields in the Meriç–Ergene River Basin.

Key words

  • benthic macroinvertebrates
  • ecological risk index
  • hypothetical risk analysis
  • rice fields
Accès libre

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

Publié en ligne: 07 Jul 2022
Pages: 224 - 238

Résumé

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

  • benthic diatoms
  • microhabitat
  • ecology
  • coastal zone
  • Gulf of Gdańsk
  • Baltic Sea
10 Articles
Accès libre

Pre-probiotic effects of different bacterial species in aquaculture: behavioral, hematological and oxidative stress responses

Publié en ligne: 07 Jul 2022
Pages: 133 - 142

Résumé

Abstract

There is very limited aquaculture research on candidate probiotics and their effects on fish physiology. In this study, acute applications of four different molecularly identified bacterial species – Brevibacillus brevis FD-1 (A), Pseudomonas fluorescens FDG-37 (B), Bacillus sphaericus FD-48 (C), and B. amyloliquefaciens TV-17C (D), with potential in aquaculture, were tested in rainbow trout (Oncorhynchus mykiss) under static conditions. Physiological changes in blood tissue [hematological indices: erythrocyte count (RBC), leukocyte count (WBC), hemoglobin (Hb), hematocrit (Hct), platelet count (PLT), mean cell hemoglobin concentration (MCHC), mean cell hemoglobin (MCH), and mean cell volume (MCV)], oxidative stress responses in liver and gill tissues [malondialdehyde (MDA) level, antioxidant enzyme activities: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathione reductase (GR), glutathione-S-transferase (GST), glucose-6-phosphate dehydrogenase (G6PD)] and acetylcholinesterase (AChE) activity in brain tissue (as neurotoxic biomarker) were investigated. Additionally, behavioral differences were recorded by measuring swimming performance to support neurotoxic findings in all treatment groups. The LC5024 value of FDG-37 strain was determined through analysis as 1.0 × 108 CFU ml-1. Inhibition of enzyme activity, increase in the MDA level, as well as significant differences in hematological indices and swimming performance were determined in rainbow trout treated with B compared to control and other bacterial groups in gills. The potential for using group FD-48 and TV-17C bacterial strains as probiotics in aquaculture is more pertinent when considering the research findings and water quality parameters.

Key words

  • fisheries
  • ecosystem management
  • probiotic
  • oxidative stress
  • LC
Accès libre

First record of the common sun star Crossaster papposus (L., 1767) in the Baltic Sea in over 100 years

Publié en ligne: 07 Jul 2022
Pages: 143 - 148

Résumé

Abstract

The rare in the German North and Baltic Sea waters and strictly protected sea star Crossaster papposus was found in 2019 and 2021 during monitoring activities in a marine protected area. This unique observation was achieved by using towed camera platform imagery along a transect in the Fehmarn Belt, which allows monitoring of a much larger area of the seafloor compared to traditional invasive grab and dredge sampling. The last time C. papposus was documented in this area was in 1871, indicating the rarity of this species in the Baltic Sea. Possible explanations for such rare records of the occurrence of this presumably native species in the study region are briefly discussed, including uncommon survival due to salinity conditions caused by prior inflows of saline water from the North Sea.

Key words

  • Fehmarn Belt
  • protected species
  • monitoring data
  • underwater imaging approach
Accès libre

Heavy metal content in coral reef-associated fish collected from the central Red Sea, Saudi Arabia

Publié en ligne: 07 Jul 2022
Pages: 149 - 157

Résumé

Abstract

The concentration of heavy metals in marine fish is important for assessing the health risks associated with fish consumption. In this study, the concentration of metals such as copper, lead and manganese were analyzed in the muscle tissue of five coral reef-associated fish species collected from the central Red Sea, Saudi Arabia. The maximum copper content of 0.183 μg g-1 (ww) was detected in fish samples. Fish samples also showed maximum lead and manganese values of 0.030 and 0.064 μg g-1 (ww), respectively. The metal concentration in fish tissue samples did not vary significantly between the fish species. In conclusion, the results obtained indicate that the content of heavy metals in the coral reef-associated fishes is below the values determined by various agencies for seafood safety.

Key words

  • seafood
  • marine fish
  • marine pollution
  • bioaccumulation
  • metal pollution index
Accès libre

Effects of diet quantity on growth performance of juvenile sea cucumbers Holothuria scabra

Publié en ligne: 07 Jul 2022
Pages: 158 - 166

Résumé

Abstract

Sea cucumbers are in high demand in the world market due to their nutritional and medicinal values. In this study, the growth performance of juvenile sea cucumbers Holothuria scabra fed with different proportions of two feeds was analyzed. Commercially available sea cucumber feed (feed-A) and formulated feed (feed-B) were used for the experiments. Animals fed with 2% feed-A showed a negative growth rate. Maximum growth was observed in animals fed with 8% feed-A and feed-B. While feed-A treated groups showed significant variation (P < 0.05) in growth performance between different percentages of diets, feed-B treated animals showed no such variation. Feed-B treated animals showed higher growth rates compared to feed-A treated sea cucumbers. Water quality parameters and anoxic conditions of the soil in culture tanks did not change due to the higher percentage of feeds. In conclusion, this study showed that diet percentage is an important factor for the optimum growth of sea cucumbers.

Key words

  • aquaculture
  • invertebrate culture
  • echinoderms
  • feed formulation
  • sandfish
  • Red Sea
Accès libre

Assessment of 8-hydroxy-2-deoxyguanosine activity, apoptosis, acetylcholinesterase and antioxidant enzyme activity in Capoeta umbla brain exposed to chlorpyrifos

Publié en ligne: 07 Jul 2022
Pages: 167 - 177

Résumé

Abstract

In this study, neurotoxic responses to exposure to chlorpyrifos (CPF) at different doses (55 and 110 μg l-1) and at different time intervals (24 and 96 h) were investigated in Siraz fish (Capoeta umbla) using 8-hydroxy 2-deoxyguanosine (8-OHdG) activity, caspase-3, acetylcholinesterase (AChE) and oxidative stress parameters [malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GR)]. In this study, the LC50 value of CPF was determined for the first time for C. umbla and calculated as 440 μg l-1. In this study, 12.5% (55 μg l-1) and 25% (110 μg l-1) of the LC50 value were used. The obtained data indicate a significant increase in the MDA level and inhibition of antioxidant enzymes in the brain (p < 0.05). Considering DNA damage and the apoptotic process, no significant changes were found in 8-OHdG and caspase-3 activity at both doses exposed for 24 h, but a significant increase was detected in both markers at 96 hours compared to the control group (p < 0.05). In the case of AChE activity, which is one of the neurotoxic markers in the brain, while inhibition was determined only at the high concentration (110 μg l-1) at the end of 24 hours, a decrease in enzyme activity was observed at the end of 96 hours in both concentration groups. In the light of all these results, we can say that CPF showed inhibitory effects on enzyme activity and inducing effects on MDA, caspase-3 and 8-OHdG levels. Based on these results, it can be concluded that CPF contributes to oxidative stress in fish and may have neurotoxic effects.

Key words

  • fish
  • brain
  • neurotoxicity
  • pesticides
  • apoptosis
  • toxicity mechanism
Accès libre

Intercellular and extracellular amino acids of different bloom species in the Mediterranean Sea

Publié en ligne: 07 Jul 2022
Pages: 178 - 188

Résumé

Abstract

The presented laboratory experiment was designed to characterize the quantity and compositional variation of algal extracellular amino acids (AAs) that may represent an alternative nutrient source in a natural environment. To resemble algal bloom scenarios, analyses were conducted in mono- and/or co-cultures of the bloom-forming species Skeletonema costatum, Scrippsiella trochoidea, Ulva fasciata, and Corallina officinalis during their active growth phase. The study revealed that S. costatum exhibited higher production of the dominant AAs than S. trochoidea. Alanine, lysine, and threonine acids are the dominant amino acids in S. costatum and S. trochoidea filtrates, which may play a role in mucus formation during mucosal phytoplankton blooms with negative ecological effects. On the other hand, aspartic, glutamine, alanine, and leucine acids are the dominant amino acids in macroalgae. In co-culture experiments, U. fasciata shows strong and rapid allelopathic activity against these two potentially harmful species. The AA production offers an advantage to species with the capacity to absorb them to form blooms. Thus, anthropogenic inorganic nutrient inputs may be less important for the development of algal blooms in coastal waters. A major difference that distinguishes this work from others is the use of specific multi-taxa cultures of phytoplankton and macroalgae. The study represents a new research effort in Alexandria waters.

Key words

  • Extracellular amino acids
Accès libre

Effects of anthropogenic activities on nutrient parameters in the North Eastern Mediterranean Sea (Bay of Sığacık/Aegean Sea)

Publié en ligne: 07 Jul 2022
Pages: 189 - 202

Résumé

Abstract

This study aims to examine the physicochemical parameters of seawater (temperature, pH, salinity, dissolved oxygen, suspended particulate matter, ammonium-nitrogen, nitrite-nitrogen, nitrate-nitrogen, and phosphate-phosphorus, burnable organic matter in the sediment), and possible effects of pollution in Sığacık Bay where different anthropogenic activities are carried out. Samples of surface seawater (0 m), bottom seawater (2 m), and sediment were collected monthly from four sampling sites between September 2013 and September 2014. Annual mean nutrient values were determined as 1.6 ± 0.14 μg.at.NH4+-N l-1, 0.1 ± 0.01 μg.at.NO2--N l-1, 0.8 ± 0.08 μg.at.NO3--N l-1, 0.7 ± 0.08 μg.at.PO43--P l-1, SPM 21.4 ± 0.33 mg l-1. The BOM content in the sediment was 5.6 ± 0.39%. As a result of the study, it was determined that Sığacık Bay was polluted by anthropogenic point and non-point source pollution. According to the water quality criteria, the bay was found to be in the group of polluted seawater in terms of phosphate phosphorus.

Key words

  • water quality
  • nitrogen
  • phosphorus
  • sediment
  • PCA
  • Aegean Sea
Accès libre

Skeletal deformities in Barbus xanthos (Teleostei: Cyprinidae) collected from the Dalaman River in southwestern Turkey

Publié en ligne: 07 Jul 2022
Pages: 203 - 211

Résumé

Abstract

In this study, skeletal anomalies such as vertebral centra deformation, lordosis (ventral curvature), and consecutive repetition of lordosis and kyphosis were examined in specimens of Barbus xanthos (Güçlü, Kalaycı, Küçük & Turan, 2020) collected from the Dalaman River, southwestern Turkey. Abnormalities of the vertebral column were observed in both thoracic and caudal vertebrae. Cases of lordosis and consecutive repetition of lordosis and kyphosis showed varying degrees of severity. Specimens with consecutive repetition of lordosis showed the most acute deformities among the cases studied, as they revealed complicated incidences of skeletal anomalies. None of the cases were fatal as they occurred in adult individuals. This study discusses the possible causes of such deformities and the usefulness of this type of study in environmental monitoring.

Key words

  • vertebral deformity
  • lordosis
  • kyphosis
  • pollution
  • environment
Accès libre

Evaluation of ecological risk analysis for benthic macroinvertebrates in paddy fields in the Meriç–Ergene River Basin (Turkish Thrace)

Publié en ligne: 07 Jul 2022
Pages: 212 - 223

Résumé

Abstract

Benthic macroinvertebrates are very important components of aquatic environments, and monitoring their population dynamics helps us understand the effects of environmental factors on ecosystems. This study aimed to determine the dynamics of benthic macroinvertebrate fauna in paddy fields in the Meriç–Ergene River Basin (Turkish Thrace region) by investigating some physicochemical environmental parameters that may affect its distribution. For this purpose, water and sediment samples were collected from paddy fields in the study area during the cultivation season, including spring, summer and autumn of 2016, taking into account the water resources that supply the rice fields (artesian water, the Meriç River, the Ergene River and Meriç–Ergene mixed water). A total of 47 taxa (on average 8953 individuals per m2) were identified at the study sites. Water samples were analyzed to determine water temperature, pH, conductivity, salinity, total dissolved solids, calcium, magnesium, total hardness, nitrite nitrogen, nitrate nitrogen, phosphate, sulfate, dissolved oxygen and pesticides, and sediment samples were analyzed to determine the content of some heavy metals, including Cd, Ni, Cu, and Mn. The biological risk index (mERM-Q) and the potential ecological risk index (RI) were applied to the data and a hypothetical ecological risk analysis was conducted using our data and data available in the literature to assess the ecological risk profile of the ecosystem based on benthic macroinvertebrates. To this end, environmental factors were grouped based on the literature as heavy metals (S1), nutrients (S2), other physicochemical parameters (S3) and pesticides (S4), while organisms were grouped as Oligochaeta, Chironomidae, Insecta and others based on the dynamics of benthic macroinvertebrates to assess pressure factors. As a result, pesticides (S4) were found to exert the strongest ecological pressure on benthic macroinvertebrate fauna in paddy fields in the Meriç–Ergene River Basin.

Key words

  • benthic macroinvertebrates
  • ecological risk index
  • hypothetical risk analysis
  • rice fields
Accès libre

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

Publié en ligne: 07 Jul 2022
Pages: 224 - 238

Résumé

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

  • benthic diatoms
  • microhabitat
  • ecology
  • coastal zone
  • Gulf of Gdańsk
  • Baltic Sea

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