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Öğe A COMPARISON OF BIOSORPTION CAPACITIES OF Cystoseira barbata AND Caulerpa racemosa USING Cd (II) AND Co (II) IONS(Parlar Scientific Publications (P S P), 2014) Cirik, Yeliz Ozudogru; Buyukates, Yesim; Merdivan, MelekThis study was conducted to compare the biosorption capacities of marine brown algae, Cystoseira barbata, and marine green algae, Caulerpa racemosa. These two algae were chemically modified by crosslinking with glutaraldehyde (GA), H3PO4, and HCl, or only washed with distilled water (DW) for use in equilibrium sorption uptake studies with Cd (II) and Co (II) ions. The pH level of the solution, contact time, initial metal concentration, mixed metal aqueous solution and desorption with different eluents were studied. A Langmuir and Freundlich isotherm analysis of the experimental data showed that the maximum metal uptake for two ions by algae were maintained when crosslinking with GA. The optimum pH value was 6 for C. barbata and 5 for C. racemosa. When the duration of the sorption process was 30 minutes, 0.1 M HCl and 0.1 M HNO3 were the most efficient eluents for these algae. FTIR and SEM analyses were performed as well. Results showed that C. barbata and C. racemosa have great potential for use as an eco-friendly agent in the process of removing Cd (II) and Co (II) ions for characterization of biomass.Öğe Assessment of physical carrying capacity of a mariculture zone designated in the Aegean Sea(Springer, 2024) Yigit, Murat; Ergun, Sebahattin; Buyukates, Yesim; Ates, A. Suat; Ozdilek, H. Goksel; Acar, SecilThe present study was conducted to evaluate the physical carrying capacity in a mariculture zone designated for cage aquaculture in the Aegean Sea (Mersin Bay, Izmir, Turkiye). Rapid assessment of carrying capacity for the approval of new investments or capacity increase requests environment-regulated timely management procedures for the sustainable development of the drastically growing cage aquaculture industry in the Mediterranean. Hence, the mathematical estimations earlier developed for the Mediterranean area have been applied for the carrying capacity assessment using the data gathered from eight fish farms operating in the area. The data collected from the farms comprised the information such as current granted production level, surface area, location depth, current speed, shore distance, and coordinates of the farm sites. The results obtained showed an estimated carrying capacity for the investigated mariculture zone as 252,852 tons which is about 18 times the current production level of 13,500 tons that was granted in total for the sum of eight cage farms in the region with a total of 50.89-ha surface area. It can be concluded that, with the condition of periodic environmental monitoring to keep the marine ecosystem below eutrophication risk, the production capacity of farms in the designated mariculture zone, comprising a surface area of 50.89 ha, could be increased by 18-fold over the present production level, which is far below the risk threshold. The findings of this study provide important support for decision-makers in the management of intensive cage aquaculture operations in the Mediterranean region.Öğe CLADOCERANS OF AN URBANIZED HARBOUR: EFFECTS OF ENVIRONMENTAL PARAMETERS ON VERTICAL DISTRIBUTION, OCCURRENCE, ABUNDANCE, AND SEASONAL VARIATION(Brill, 2009) Buyukates, Yesim; Inanmaz, Oezguer E.The seasonal succession patterns of species of Cladocera with respect to changes in some environmental and biological parameters were examined in a harbour located at Kepez, Dardanelles from 11 April 2006 to 12 April 2007. For this study, environmental parameters and zooplankton data were analysed for one station and sampling trips were conducted every two weeks. Cladoceran abundance varied widely throughout the sampling period, exceeding similar to 87% of total zooplankton, especially during the warmer seasons. The cladoceran community was mainly composed of Penilia avirostris, Pleopsis polyphemoides, and Evadne nordmanni, the first one occurring from late spring through early fall, and the latter two from early spring to early summer. Salinity and temperature seemed to have little or no effect on the distribution, abundance, and variability of the cladocerans in the system, indicating factors other than non-biological environmental parameters, such as competition with other groups of zooplankton, food availability and/or quality, have the greatest effects on cladoceran species composition.Öğe Co-occurring and opposing freshwater inflow effects on phytoplankton biomass, productivity and community composition of Galveston Bay, USA(Inter-Research, 2013) Roelke, Daniel L.; Li, Hsiu-Ping; Hayden, Natanya J.; Miller, Carrie J.; Davis, Stephen E.; Quigg, Antonietta; Buyukates, YesimFreshwater inflow effects on phytoplankton have long interested aquatic ecologists. More recently, timing and magnitude of inflow events have been a focus as they can be strong drivers of phytoplankton diversity and productivity. In the present research, we empirically and theoretically explored the effects of inflow events on phytoplankton of Galveston Bay, Texas, a bay system whose freshwater inflow arises primarily from 2 rivers, the San Jacinto and Trinity. We found that conditions in the upper regions of Galveston Bay adjacent to these rivers had opposing influences on phytoplankton. In the region near the San Jacinto River, inflows mostly stimulated biomass and productivity, while in the region near the Trinity River, inflows had the opposite effect. This suggested that the phytoplankton reproductive growth rate was at times nutrient limited near the San Jacinto River and that population growth responded rapidly to nutrient loadings. This also suggested that population growth was controlled at times by other processes near the Trinity River, thereby negating the effects of nutrient loadings. Decreased phytoplankton biomass occurred in this region due, in part, to hydraulic displacement. These co-occurring and opposing inflow effects extended into the mid- and lower bay regions, but the extension varied in time and location with no seasonal trend. Such observations underscore the challenges of predicting system responses to altered inflows. Phytoplankton composition was also affected by inflows, and some taxonomic trends were regionally specific. Attributes of phytoplankton relating to use of alternative sources of nutrition, differential growth rates and immigration of euryhaline species from rivers likely influenced the spatiotemporal distribution of taxa.Öğe Daily Variations of Chlorophyll-a, Environmental Parameters And Nutrients: Saricay Creek As An Exemplary (Canakkale, Turkey)(Foundation Environmental Protection & Research-Fepr, 2009) Odabasi, Serpil; Buyukates, YesimIn this study, it was aimed to examine the relationships among chlorophyll-a, environmental parameters such as temperature, salinity, pH and dissolved oxygen (DO) and nutrients Total Nitrogen, Total Phosphorus, Ammonia-nitrogen and Silicate (TN, TP, NH4 and SiO2, respectively) between 8 July and 6 August, 2004 in Sari ay Creek. During sampling periods, temperature values followed the usual seasonal values, while DO and pH changed considerably, and ranged between 1,23-13,1 mg l(-1) and 7,48-9,33, respectively. Chlorophyll-a concentration changed between 0,98-34,45 mu g l(-1), while TP, TN, NH4 and SiO2 ranged between 0,21-0,91 mg l(-1), 4,78-107,24 mg l(-1), 0,04-3,68 mg l(-1), 0,16-22,4 mg l(-1), respectively There was no significant correlation among chlorophyll-a and nutrients. However, there was significant correlation between environmental parameters, such as pH (p=0,23), temperature (p=0,28), DO (p=0,23) and chlorophyll-a (p<0.01). Results of the environmental parameters indicated that the pollution level increased irregularly in a short time and there was on instant reverse relation between inorganic nutrients and chlorophyll-a.Öğe Environmental Characteristics in a Fish Farm with Copper Alloy Cage System in the Dardanelles(Zoological Soc Pakistan, 2020) Uzundumlu, Sinan; Buyukates, Yesim; Yigit, Murat; Bulut, Musa; Gurses, Ridvan Kaan; Celikkol, BarbarosThis study was conducted in a copper alloy cage fish farm to observe the environmental properties of the marine system. Water quality parameters such as temperature, salinity, pH and dissolved oxygen, total suspended solids, chlorophyll-a and inorganic nutrients such as NO2+NO3, NH4, PO4 and SiO2 were observed between May 2014 and September 2014 in the study area. The observed results were compared with acceptable limits pronounced in international organizations such as EPA and FAO, and national organizations such as WPCR and RTMAF as well as the previous studies conducted in the region. According to the results, a decrease in dissolved oxygen and pH was observed at the farm while increases in inorganic nutrients except for ammonia were recorded. TSS values showed significant positive correlation with TP, indicating that TSS was supported by fecal pellets or unused fish feed in the cage system. MDS analysis results showed that TSS, chlorophyll-a and TP were similar throughout the sampling period. The study showed that copper alloy cage system did not have any negative impact on the marine system, compared with the limits provided by FAO, EPA, WPCR and RTMAF as well as with previously conducted studies in the region.Öğe Health Risks Associated with Trace Metals in Gilthead Seabream (Sparus aurata) from Copper Alloy and Antifouling-Coated Polymer Nets(Springer International Publishing Ag, 2020) Yigit, Murat; Dwyer, Robert; Yilmaz, Sevdan; Bulut, Musa; Ozalp, Baris; Buyukates, Yesim; Ergun, SebahattinThe aim of the present study was to evaluate risk levels of trace elements in gilthead seabream (Sparus aurata) from conventional polymer nets and copper alloy mesh with reference to hazard levels and maximum allowable limits for human consumption. Bioaccumulation of trace metals in muscle tissues of fish from copper-alloy mesh, and antifoulant-coated net presented elevated levels in the order of Fe(5.76) > Zn(5.56) > Cu(0.53) > Mn(0.28), and Zn(5.20) > Fe(3.97) > Cu(0.56) > Mn(0.26), respectively, compared to the untreated polymer net pen as Zn(3.61) > Fe(3.12) > Cu(0.44) > Mn(0.16) mg/kg wet weight. However, metal levels in fish harvested from all experimental cages did not exceed maximum permitted levels for seafood safety. Target hazard quotients and total hazard indexes, calculated for the evaluation of non-carcinogenic health risks via metal intake through the consumption of possibly contaminated fish, were found lower than one (THQ < 1; THI < 1). Maximum allowable consumption levels (kg/day/person) were found in the order of Mn(39.27) > Cu(18.87) > Fe(7.81) > Zn(7.19), Mn(42.31) > Cu(17.86) > Fe(11.34) > Zn(7.69), and Mn(68.75) > Cu(22.73) > Fe(15.96) > Zn(11.08) for fish from copper-alloy mesh, antifoulant-treated net, and untreated polymer net pen, respectively. The results of this study showed that the trace metals in the edible muscle of fish from both copper alloy and antifoulant-coated net pens were below human health risk levels, according to the limits suggested by US Food and Drug Administration and EU Regulations for Seafood Consumption.Öğe Heavy metals uptake from aqueous solutions using marine algae (Colpomenia sinuosa): kinetics and isotherms(Taylor & Francis Ltd, 2012) Cirik, Yeliz; Bekci, Zehra Molu; Buyukates, Yesim; Ak, Ilknur; Merdivan, MelekThe adsorption of copper, zinc, cobalt, lead and cadmium ions onto Colpomenia sinuosa was studied as a function of contact time, initial metal ion concentration and initial pH. In addition, desorption studies were performed. Characterisation of this adsorbent was also confirmed by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) analysis. Batch adsorption experimental data were analysed using Langmuir, Freundlich and Dubinin-Raduschkevich (D-R) adsorption isotherms. The results indicated that the biosorption equilibrium was well described by both the Freudlich and D-R isotherms. Moreover, sorption kinetics was performed and it was observed that equilibrium was reached in <60 min, which could be described by the pseudo-second-order kinetic model for all heavy metals. The sorption of heavy metals onto the biomass was largely dependent on the initial solution pH. The elution efficiency for heavy metal ions desorption from C. sinuosa was determined for 0.1 M HCl, 1.0 M HCl and 1.0 M HNO3. Desorption efficiency and also adsorption capacity were highest for Pb(II). The results indicate that C. sinuosa has great potential for the removal of heavy metals in an ecofriendly process.Öğe Human exposure to trace elements via farmed and cage aggregated wild Axillary seabream (Pagellus acarne) in a copper alloy cage site in the Northern Aegean Sea(Elsevier Gmbh, 2018) Yigit, Murat; Dwyer, Robert; Celikkol, Barbaros; Yilmaz, Sevdan; Bulut, Musa; Buyukates, Yesim; Kesbic, Osman S.Axillary seabream (Pagellus acarne) farmed in a copper alloy mesh pen and wild individuals of P. acarne aggregated near the copper-alloy cages presented higher concentrations of trace metals in the liver, skin and gills than in fish muscle tissues in two batches of small and large fish sizes. Elevated mean levels of metals (mg kg(-1)) in muscle tissues in both small and large fish size groups were observed in the rank order of Zn(3.43) > Fe (3.01) > Cu(0.59) > Mn(0.13) and Fe(3.82) > Zn(3.32) > Cu(0.62) > Mn(0.17) for copper cage-farmed fish, relative to ranked mean levels for Zn(2.64) > Fe(1.95) > Cu(0.25) > Mn(0.09) and Fe(5.79) > Zn(3.58) > Cu (0.58) > Mn(0.28) for the copper cage-aggregated wild fish. Nevertheless, trace metal concentrations in fish harvested from the copper cage or those of the cage-aggregated wild individuals in both size groups were far below maximum levels of seafood safety recommended by USEPA and FAO/WHO. Target hazard quotients, calculated to estimate the non-carcinogenic health risks of metals by consuming these fish, were below 1 (THQ < 1), indicating that there were no potential health risks for humans when consuming copper-caged fish or wild-caught individuals aggregated around the copper mesh pen, with respect to the limits suggested by US Food and Drug Administration and EU Regulations for Seafood Consumption.Öğe Potential Impacts of a Waste Reception Facility on Stable Isotope Composition of Zooplankton and Particulate Organic Matter in the Dardanelles(Hard, 2020) Uzundumlu, Sinan; Buyukates, Yesim; Ates, A. SuatIn this study, seasonal stable isotope compositions of zooplankton and particulate organic matter were analyzed from the coastal zone in Kepez Harbor, the discharge point of a waste treatment plant. The results were compared with the results of a control station located 10 km away from the harbor. Zooplankton samples were collected horizontally with a 200 mu m mesh plankton net from the surface waters. POM samples were collected with a 5L Nansen bottle and filtered through precombusted GF/F filters. Variables such as temperature, salinity, chlorophyll-a as well as oil-grease and chemical oxygen demand were also determined in the study sites. The salinity values in the control station were significantly higher than the harbor station through the whole year. The delta C-13 values of POM in the control station were significantly higher than the values observed in the harbor station. The delta N-15 values of zooplankton in the harbor were higher than the values obtained in the control station; however, the differences were not significant. The values of oil-grease obtained in two stations were lower than the values pronounced in EPA, EU, and Turkish Regulations. The study showed that the stable isotope compositions were affected by terrestrial inputs and high currents rather than the facilities comprised in the harbor.Öğe Stable isotope compositions of dominant zooplankton species in relation to environmental factors in the Dardanelles(Inst Bioloska Istrazivanja Sinisa Stankovic, 2019) Uzundumlu, Sinan; Buyukates, YesimSamples were collected seasonally from three stations in the Dardanelles between April 2016 and October 2017 to determine the effects of biological and physicochemical properties of the coastal system on the isotopic compositions of the most abundant copepod species, Acartia clausi and Calanus helgolandicus, and a cladoceran, Penilia avirostris. Plankton samples were collected horizontally with a 200-mu m-mesh plankton net and isotopic analyses were performed by mass spectrometry after identification to species level. Total zooplankton abundance reached its maximum in spring and summer. The delta C-13 values of copepods showed statistically significant differences both between stations and seasons. As a selective feeder, C. helgolandicus had the highest values in both delta C-13 and delta N-15. Being a filter feeder, P. avirostris distinctly differed from C. helgolandicus and A. clausi. Enrichment was observed in delta N-15 values of copepods in winter, when the highest values of total suspended solids and chlorophyll-a were determined. The results showed that delta C-13 values of the copepods were under the influence of environmental and biological factors. Additionally, dietary differences between herbivorous groups and other groups were clearly demonstrated, as well as differences in the diets of filter-feeding and selectively-feeding zooplanktonic species.Öğe Temporal variations in hematological, immunological and serum biochemical parameters of rainbow trout (Oncorhynchus mykiss) acclimated to high-saline water in the Northern Aegean Sea(Walter De Gruyter Gmbh, 2023) Buyukates, Yesim; Kesbic, Osman; Yigit, Murat; Yilmaz, Sevdan; Ergun, Sebahattin; Bulut, Musa; Ozalp, BansThe present study evaluated the health status of rainbow trout (30.24 +/- 5.34 g) acclimated to high-saline water (28 parts per thousand). Among adaptation procedures, gradually-acclimated (for 48 h) fish showed best performance, which were then introduced to the offshore cage-farm for further monitoring of fish health in marine environment over a long-term period of 100 days, until harvest weight of 319.9 +/- 48.51 g. Fish health and welfare was evaluated by means of biochemical parameters (viscerasomatic index, hepatosomatic index, mesenteric fat index, and spleen somatic index), hematological parameters (serum glucose, triglyceride, cholesterol, total protein, albumin, globulin), and immune parameters (lysozyme, myeloperoxidase, respiratory burst and potential killing values). Gradual acclimation to high-saline water did not show any adverse effects on health parameters. No significant differences were found in biometric measures (P>0.05). However, a time-dependent increase was recorded in hematology markers (P<0.05) after seawater transfer, and the health status improved over long-term from March 7 to June 14, 2018. All serum biochemical markers, except the total protein showed significant alterations (P<0.05) in long-term but without detrimental influence by day-100. Therefore, it seems possible to expand trout farms from brackish water sites to higher saline environments up to 28 parts per thousand salinity, with no detrimental impacts on fish health, that in turns may significantly contribute to the extension of potential aquaculture sites to wider areas.Öğe Temporal variations in vertical distribution and occurrence of marine cladocerans in an urbanized harbour, Dardanelles, Turkey(Brill, 2007) Buyukates, Yesim; Inanmaz, Oezguer E.Cladoceran species abundance, occurrence, and distribution with respect to temperature, salinity, and chlorophyll-a concentration were investigated in an urbanized harbour located at Kepez, Dardanelles from April 2005 to April 2006. Field samplings were performed weekly and environmental parameters were measured in situ. The most common species of the five cladocerans recorded at the study site were Penilia avirostris with 49%, followed by Pleopsis polyphemoides, Pseudevadne tergestina, Evadne nordmanni, and E. spinifera, with 43%, 26%, 14%, and 2%, respectively. Although the cladocerans found at the study site are characteristics species of the Black Sea, the Sea of Marmara, and the northern Aegean Sea, their abundance, timing of occurrence, and maximum densities appear to have changed considerably in comparison with previous reports in the literature.Öğe The Annual Mesozooplankton Dynamics and Influence of Environmental Parameters in an Urbanized Harbor (Kepez Harbor-Dardanelles Strait, Turkey)(Foundation Environmental Protection & Research-Fepr, 2010) Buyukates, Yesim; Inanmaz, Ozgur EmekWeekly field samplings were performed at the Kepez Harbor located at the Dardanelles Strait for temperature, salinity, Secchi disk, dissolved oxygen, chlorophyll-a and nutrient concentrations, zooplankton abundance, and community structure from 26 April 2005 to 25 April 2006. Zooplankton samples were collected Using a plankton net with a mesh size of 1,80 mu m for the mesozooplankton and vertical tows were conducted between 0-5 m 10-15 m, and 15-20 m. Whole water samples were also collected for microzooplankton. All mesozooplankton groups increased in number starting at the end of May through June. Copepoda dominated the surface and mixed layer during the early spring and Acartia clausi was the most Abundant species when compared to the others. Cladocera showed a clear seasonal succession pattern in the study site and were mainly composed of Penilia avirostris, Pleopsis polyphemoides, and Evadne nordmanni. Oikopleura dioica, the only representative of the appendicularians, reached its maximum abundance during mid summer. The zooplankton species composition in the sampling site was diverse and a unique two layer flow regime of the system allowed us to observe both the Mediterranean and the Black Sea influence on the organisms.
