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    A COMPARATIVE ANALYSIS OF WATER QUALITY ASSESSMENT METHODS FOR HEAVY METAL POLLUTION IN KARASU STREAM, TURKEY
    (Parlar Scientific Publications (P S P), 2013) Sonmez, Adem Yavuz; Hisar, Olcay; Yanik, Telat
    Heavy metals are among the most persistent of pollutants in aquatic systems due to their resistance to decomposition in nature. Four assessment methods (two pollution indexes and two fuzzy mathematical models - single-factor deciding and weighted average models) were used to check the level and characteristics of heavy metal pollution in the Karasu stream water. Several heavy metals such as Copper (Cu), Zinc (Zn), Manganese (Mn), Lead (Pb), Nickel (Ni), Cadmium (Cd) and Iron (Fe) were tested with these methods. A data set (12 months, total 180 measurements) was collected from 5 sampling points (A-E) of the River. The used criteria were classes, I-IV represents from clear to polluted one. Water quality was assessed as class IV from all water samples collected from the each station with single-factor index method. It was identified to be class IV from the samples of A, B, C and D stations, and class Ill from the sample of E station with the comprehensive index model. By using the fuzzy mathematical methods, the water quality were determined as classes of IV, IV, IV, II and II from the water samples of A, B, C, D and E stations respectively. Introduction of membership degree and weight of each factor to fuzzy mathematical models made the methods more reasonable in the field of water quality assessment. Therefore, these fuzzy mathematical methods might be quite convenient in evaluation of water pollution and classification considering the results of the present study.
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    An Adaptive Neuro-Fuzzy Inference System (ANFIS) to Predict of Cadmium (Cd) Concentrations in the Filyos River, Turkey
    (Central Fisheries Research Inst, 2018) Sonmez, Adem Yavuz; Kale, Semih; Ozdemir, Rahmi Can; Kadak, Ali Eslem
    Water quality is one of the main characteristics of a river system and prediction of water quality is the key factor in water resource management. Different physical, biological and chemical parameters including heavy metals can be used to assess river water quality. Evaluation of the water quality in the rivers is quite difficult and requires more time and effort because of the fact that many factors affect water quality. Traditional data processing methods are insufficient to solve this problem. Therefore, in this study, an adaptive neuro-fuzzy inference system (ANFIS) model was developed to predict the concentrations of cadmium (Cd) in the Filyos River, Turkey. For this purpose, water samples collected at 7 sampling locations in the river during December 2014-2015 were used to develop ANFIS model. The available data set was apportioned into two separate sections for training and testing the ANFIS model. Developed models aimed to use the least parameters to estimate Cd concentration. As a result, a relatively higher correlation (R-2=0.91) was found between observed and modelled Cd concentrations. The results indicated that the ANFIS model gave reasonable estimates for the concentrations of Cd with a high degree accuracy and robustness. In conclusion, this paper suggests that ANFIS methodology produce very successful findings and has the ability to predict Cd concentration in water resources. The outcomes of this research provide more information, simulation, and prediction about heavy metal concentration in natural aquatic ecosystems. Therefore, ANFIS can be used in further researches on water quality monitoring.
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    An assessment of the effects of climate change on annual streamflow in rivers in Western Turkey
    (Inderscience Enterprises Ltd, 2018) Kale, Semih; Hisar, Olcay; Sonmez, Adem Yavuz; Mutlu, Fatih; Filho, Walter Leal
    Global warming and its impacts are known to cause serious problems in sustainability of natural resources. In this study, change-point analysis and trend analysis were applied to climatic (temperature, precipitation, evaporation) and streamflow data for Tuzla, Gediz and Buyuk Menderes rivers. Box-Jenkins technique and ARIMA model were used for trend analysis. Results showed that there were decreases in streamflow of all rivers. The paper suggests that climate change effects on streamflow could be changeable and that many factors (anthropogenic effects, geographical location, agricultural activities) should be considered. Management strategies specified regionally are required to mitigate the potential climate change effects.
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    Climate change effects on annual streamflow of Filyos River (Turkey)
    (Iwa Publishing, 2020) Sonmez, Adem Yavuz; Kale, Semih
    The main purpose of this study was to estimate possible climate change effects on the annual streamflow of Filyos River (Turkey). Data for annual streamflow and climatic parameters were obtained from streamflow gauging stations on the river and Bartin, Karabuk, Zonguldak meteorological observation stations. Time series analysis was performed on 46 years of annual streamflow data and 57 years of annual mean climatic data from three monitoring stations to understand the trends. Pettitt change-point analysis was applied to determine the change time and trend analysis was performed to forecast trends. To reveal the relationship between climatic parameters and streamflow, correlation tests, namely, Spearman's rho and Kendall's tau were applied. The results of Pettitt change-point analysis pointed to 2000 as the change year for streamflow. Change years for temperature and precipitation were detected as 1997 and 2000, respectively. Trend analysis results indicated decreasing trends in the streamflow and precipitation, and increasing trend in temperature. These changes were found statistically significant for streamflow (p < 0.05) and temperature (p < 0.01). Also, a statistically significant (p < 0.05) correlation was found between streamflow and precipitation. In conclusion, decreasing precipitation and increasing temperature as a result of climate change initiated a decrease in the river streamflow.
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    Effects of Dietary Supplementation of Herbal Oils Containing 1,8-cineole, Carvacrol or Pulegone on Growth Performance, Survival, Fatty Acid Composition, and Liver and Kidney Histology of Rainbow Trout (Oncorhynchus mykiss) Fingerlings
    (Central Fisheries Research Inst, 2015) Sonmez, Adem Yavuz; Bilen, Soner; Albayrak, Mevlut; Yılmaz, Sevdan; Biswas, Gouranga; Hisar, Olcay; Yanik, Talat
    A feeding trial was performed to assess any beneficial effect of three herbal oils; mint, thyme and sage oils containing 74 g kg-1 pulegone, 77 g kg-1 carvacrol and 76 g kg-11,8-cineole, respectively on growth performance, survival, fatty acid composition, and liver and kidney histology of rainbow trout (Oncorhynchus mykiss). Herbal oils were added at 0.5 %, 1.0% and 1.5 % concentrations to a fish meal-based control diet, and each diet was fed to triplicate groups of rainbow trout fingerlings for 60 days with growth parameters recorded weekly. Results showed that FCR was affected negatively in all mint oil diet fed groups where it was higher than that of control and other groups (P<0.05). The lowest FCR values were recorded in the thyme and sage oil containing diets fed groups (P<0.05) with no significant differences between these two groups. SGR was also found lower in mint oil groups than in control. The highest SGR was recorded in thyme and sage oil fed groups (P<0.05). Survival was similar in fish fed with diets containing thyme, sage oil and control diet (P>0.05). However, survival was the lowest in fish fed with mint oil supplemented diets(P<0.05). Whole body fatty acid profiles except total saturated fatty acids are closely influenced by dietary herbal oil administrations. Total polyunsaturated n-6 fatty acid was lowest in 1 % thyme oil and all sage oil diet fed groups (P<0.05). Total polyunsaturated n-3 fatty acid was similar between control and sage oil supplemented groups, but in other groups it was significantly decreased (P<0.05). EPA/DHA ratio was observed significantly low in 1.5 % thyme oil and all groups of sage oil fed fish. There were no histological differences observed in liver or kidney of fish fedwith control and 0.5 % and 1 % thyme and sage oil supplemented diets. The present results showed positive effects of thyme and sage herbal essential oil supplemented diets on growth performance and fatty acid utilization and these oils may be useful feed supplements in production of rainbow trout.
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    Fuzzy Logic Evaluation of Water Quality Classification for Heavy Metal Pollution in Karasu Stream, Turkey
    (Foundation Environmental Protection & Research-Fepr, 2013) Sonmez, Adem Yavuz; Hasiloglu, Samet; Hisar, Olcay; Aras Mehan, Hatice Nur; Kaya, Hasan
    Traditional water quality evaluation methods use discrete form that involve upper and lower limits, and the concentrations values are equally important when the values are near to or far away from the limits. Moreover, each quality parameter might belong to one of the four classes; therefore differences of the classes of the parameters may be vagueness. In this study, an index model is purposed for quality evaluation of water quality classification using fuzzy logic. For that purpose, a data set (12 months, total 180 measurements) about several heavy metals such as Copper (Cu), Zinc (Zn), Manganese (Mn), Lead (Pb), Nickel (Ni), Cadmium (Cd) and Iron (Fe) was collected from 5 monitoring stations in Karasu River. After that, fuzzy logic assessment method was used to quality evaluation for heavy metal pollution in Karasu stream. In conclusion, it was supposed that fuzzy logic evaluation method may also be used as an alternative tool for decision-making in environmental management.
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    Growth performance and antioxidant enzyme activities in rainbow trout (Oncorhynchus mykiss) juveniles fed diets supplemented with sage, mint and thyme oils
    (Springer, 2015) Sonmez, Adem Yavuz; Bilen, Soner; Alak, Gonca; Hisar, Olcay; Yanik, Talat; Biswas, Gouranga
    This study evaluated effects of dietary supplementation of sage (Salvia officinalis), mint (Mentha spicata) and thyme (Thymus vulgaris) oils on growth performance, lipid peroxidation level (melondialdehyde, MDA) and liver antioxidant enzyme activities (superoxide dismutase, SOD; catalase, CAT; glucose-6-phosphate dehydrogenase, G6PD; glutathione reductase, GR; glutathione-S-transferase, GST and glutathione peroxidase, GPx) in rainbow trout (Oncorhynchus mykiss) juveniles. For this purpose, triplicate groups of rainbow trout were fed daily ad libitum with diets containing sage, mint and thyme oils at 500, 1,000 and 1,500 mg kg(-1) for 60 days. While weight gain percentage of fish fed the diets containing sage and thyme oils was significantly higher than the control group, that of fish fed mint oil was the lowest. Similarly, specific growth rate was found to be the highest in all groups of the sage and thyme oil feeding and the lowest in the mint groups. Moreover, feed conversion ratio was significantly higher in the mint oil administered groups. Survival rate was also significantly reduced in the fish fed the diet containing mint oil. It was observed that SOD, G6PD and GPx activities were significantly increased in liver tissues of all the treated fish groups compared to that of control diet-fed group. However, CAT, GST and GR activities were significantly decreased in experimental diet-fed fish groups at the end of the experiment. On the other hand, a significant reduction was found in MDA levels in the fish fed the diets with sage and thyme oils compared to control and mint diets on the 30th and 60th days of experiment. Overall, dietary inclusion of sage and thyme oils is effective in enhancing rainbow trout growth, reduction in MDA and least changing antioxidant enzyme activities at a low level of 500 mg kg(-1) diet, and they can be used as important feed supplements for rainbow trout production.
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    Melatonin Implantation in Preovulatory Rainbow Trout (Oncorhynchus mykiss) under Short Photoperiod Regime Reduces Egg Quality
    (Central Fisheries Research Inst, 2014) Sonmez, Adem Yavuz; Aydin, Ilhan; Hisar, Olcay; Kaya, Hasan; Hisar, Sukriye Aras
    As in other vertebrates, the pineal organ in salmonids receives photic information directly through specialized photoreceptor cells to synchronize both daily and seasonal behavioral and physiological events, including the reproductive. In this study, the effect of a melatonin implantation before the preovulatory period on egg quality was investigated in rainbow trout (Oncorhynchus mykiss) adults. Fish were exposed to two different lighting regimes [(constant short photoperiod (SP) of 6h light/18h dark) or natural photoperiod (NP) of 9h light/15h dark) with sub groups receiving a slow-release melatonin implant ((containing 9 mg melatonin hormone (MLT)) or sham implant. Melatonin implanted fish showed supraphysiological plasma MLT concentration during the 45 days after implantation. The spawning period started at the same time in all groups after implantation, although eggs were obtained from females exposed to SP lighting regimes only or SP lighting regimes plus implanted MLT exhibited significantly lower quality characterized by lower hatching rate and survival to first feeding than that of females expose to NP. In conclusion, it was determined that implantation of MLT in preovulatory rainbow trout females causes a decrease in egg quality. However, future investigations should be conducted to ascertain the MLT dose required for and time of implantation in rainbow trout.
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    Metals in Two Species of Fish in Karasu River
    (Springer, 2012) Sonmez, Adem Yavuz; Yaganoglu, A. Mutlu; Arslan, Gokhan; Hisar, Olcay
    In this study, cadmium (Cd), copper (Cu), iron (Fe), nickel (Ni), lead (Pb) and zinc (Zn) levels were determined in the tissues (muscle, liver and gills) of two fish species, Capoeta capoeta umbla and Chalcalburnus mosullensis, collected from three stations of the Karasu River. The lowest metal accumulation was detected in the muscle tissues. Moreover there was some variability in the metal concentrations measured in the same tissues from samples obtained from the three different stations. A positive correlation was observed for the concentration of metal pairs Fe-Cu, Fe-Zn, Ni-Pb, Pb-Zn. These findings were also compared with national and international food standards, and Pb and Cd concentrations were determined to be above the level set by the standards. In conclusion, it was supposed that excessive consumption of these two fish species, which already occurs in this region, might pose a public health risk.
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    The sexually dimorphic adipose fin is an androgen target tissue in the brown trout (Salmo trutta fario)
    (Springer, 2013) Hisar, Olcay; Sonmez, Adem Yavuz; Hisar, Sukriye Aras; Budak, Harun; Gultepe, Nejdet
    An investigation has been described on the relationship of body length, age and sex with adipose fin length and the number of androgen receptor (AR)-containing cells in the adipose fin as a secondary sexual characteristic for brown trout (Salmo trutta fario). Firstly, body and adipose fin lengths of 2- to 5-year-old brown trout were measured. Thereafter, these fish were killed by decapitation, then their sexes were determined, and adipose fins were excised. The cellular bases of AR binding activities in the adipose fins were analyzed with an antibody against human/rat AR peptide. Immunocytochemistry and western blotting techniques were performed with this antibody. Analysis of morphological measurements indicated that body length and age had a linear relationship with adipose fin length. The coefficients of determination for the body length and age were 0.92 and 0.85 in the male fish and 0.76 and 0.73 in the female fish against the adipose fin length, respectively. At 2 years of age, cells in the adipose fin did not exhibit AR immunoreactivity. However, AR-immunopositive cells were abundant in the adipose fin of 3- to 5-year-old fish. Moreover, the number of AR-immunopositive cells was significantly (P < 0.05) high in males and increased with age. These observations indicate that the adipose fin in the brown trout is a probable target for androgen action and that tissue function or development may to some extent be androgen dependent. In addition, it is likely that such an effect will be mediated by specific androgen receptors.
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    Trend analysis and forecasting of the Gokirmak River streamflow (Turkey)
    (Walter De Gruyter Gmbh, 2020) Arslan, Gokhan; Kale, Semih; Sonmez, Adem Yavuz
    The objective of this paper is to determine the trend and to estimate the streamflow of the Gokirmak River. The possible trend of the streamflow was forecasted using an autoregressive integrated moving average (ARIMA) model. Time series and trend analyses were performed using monthly streamflow data for the period between 1999 and 2014. Pettitt's change point analysis was employed to detect the time of change for historical streamflow time series. Kendall's tau and Spearman's rho tests were also conducted. The results of the change point analysis determined the change point as 2008. The time series analysis showed that the streamflow of the river had a decreasing trend from the past to the present. Results of the trend analysis forecasted a decreasing trend for the streamflow in the future. The decreasing trend in the streamflow may be related to climate change. This paper provides preliminary knowledge of the streamflow trend for the Gokirmak River.