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Dissolved organic nitrogen can cause undesirable environmental problems in aquatic environments, such as eutrophication, nitrogenous disinfection by-product formation, and a decrease in the amount of dissolved oxygen. 25–80% of the total dissolved nitrogen (TDN) in the effluent of wastewater treatment plants is dissolved organic nitrogen (DON) form. As a result of these concerns, the biodegradability and management of DON is important issue for domestic/industrial wastewater treatment. Dairy products are widely consumed in Turkey and dairy industry wastewater has a high organic nitrogen content. In this study, the biodegradability of wastewater samples obtained from yoghurt and cheese production industries was investigated. The biodegradability of wastewater samples was determined by using a mixed bacteria culture and identified between 72.2 and 81.7% for yoghurt production wastewater and 19.1–20.1% for cheese production wastewater. BDON/TDN ratio was found as 65.4–71.9% and 16.5–17.5% ranges for yoghurt and cheese production wastewaters, respectively. Although both are released from dairy production, it has been determined that white cheese production wastewater has a very low biodegradability compared to yoghurt production wastewater. It is thought that the results of this study will contribute to the evaluation of the removal efficiency in other industrial facilities and domestic wastewater treatment plants. [ABSTRACT FROM AUTHOR]

The Kırklareli Reservoir, located in the Meriç-Ergene River Basin, is an important drinking/industrial freshwater resource of the Kırklareli Province. In order to ensure the sustainable use of this important reservoir, its current situation should be examined periodically and evaluated by multivariate analyses. For this reason, water samples were taken between the dates April 2018 and February 2019 at monthly intervals from 3 different stations. The data on the environmental and physicochemical variables (water temperature, dissolved oxygen, pH, salinity, conductivity, total dissolved solids, chlorophyll-a, light permeability, fluoride, chloride, NO2-N, NO3-N, PO4, SO4 and essential/potentially toxic elements) were measured and evaluated according to the classes of surface water quality control regulation of Turkey. The parameters exceeding first-class water quality values (chlorophyll-a, pH, NO2-N, chloride, selenium) were mapped in GIS using the spline integration approach. In addition, the sodium absorbtion ratio, Kelly index values and magnesium ratio, were calculated to evaluate the water quality for agricultural irrigation water standards. The water quality of the reservoir was evaluated using multivariance analyses (Bray-Curtis similarity index, correspondence analyses, Pearson correlation index). As a result, it was emphasized that the use of the GIS approach is a potential useful method for monitoring the sustainable water quality of the Kırklareli Reservoir, which was determined to have an oligomesotrophic character. [ABSTRACT FROM AUTHOR]

Copyright of Ege Journal of Fisheries & Aquatic Sciences (EgeJFAS) / Su Ürünleri Dergisi is the property of Ege Journal of Fisheries & Aquatic Sciences (EgeJFAS) / Su Urunleri Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of SDU Journal of Engineering Sciences & Design / Mühendislik Bilimleri ve Tasarım Dergisi is the property of Journal of Engineering Sciences & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Baghdad Science Journal is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Wetland face environmental problems due to some reasons such as drought, rapid population and rapid developments in technology. Karataş Lake is located within the Lakes Region in Türkiye and has also of great economically, ecologically and ornithologically importance. Unfortunately, it completely dried out in 2021 due to sufficient rainfall, groundwater withdrawal and global climate change. In 2022, the lake started to hold water again. This study is important because it is one of the last studies before the lake dries up and first study to evaluate some heavy metals and selenium pollution using some indices. In this study, which was carried out between October 2019–July 2020, some heavy metals and selenium concentrations were determined in water of Karataş Lake seasonally and evaluated pollution degree of lake water using some indices and statistical analysis. Water temperature, pH, electrical conductivity and dissolved oxygen levels were measured in situ using YSI 556 MPS. For heavy metal analysis, water samples were taken, acidified to a pH of <2, stored at 4 °C and analyzed directly using ICP-OES (Agilent 5110). Pb and Se in all seasons were below detection limit. The analyzed metals sorted as; Cd < Mo < Cr < Cu < Mn < Zn < Ni < Fe. Generally, heavy metals were increased in autumn and decreased in spring. According to some water quality standards for drinking water, Fe levels were higher than the permissible levels for drinking water in all seasons (TSE, 2005; EPA, 2018; EU, 2020), Mn in autumn (TSE, 2005; EPA, 2018; EU, 2020), Ni in autumn and summer (TSE, 2005; EU, 2020). Water Quality Index (WQI), Heavy Metal Pollution Index (HPI) and Heavy Metal Evaluation Index (HEI) values were calculated in Karataş Lake to determine pollution degree. Depend on WQI results, lake water was in good category in autumn, winter and spring while poor category in summer. The lake water samples based on HPI and HEI values are in the low contamination category. The lake is still struggling with environmental problems. If necessary precautions are not taken for the future of the lake, the lake may dry out again. The results of this study will help the authorities in terms of preventing re-drying, sustainability of the lake and management of the region. This study will be also a reference for future studies. • Some heavy metals in water in Karataş Lake were investigated. The analyzed metals sorted as; Cd < Mo < Cr < Cu < Mn < Zn < Ni < Fe. • Lake water was in IV. class water quality in summer based on temperature and pH, III. class water quality with dissolved oxygen values and II. class water quality with electrical conductivity in all seasons. • Based on the heavy metals values, generally Karataş Lake water was classified as category I. • Fe levels were higher than the permissible levels for drinking water in all seasons, Mn in autumn, Ni in spring and summer • 1. Depend on WQI, lake water was in poor category in summer and good category in other seasons. All water samples based on HPI and HEI, are in low contamination category. [ABSTRACT FROM AUTHOR]

This study was carried out to investigate the parasite prevalence on rainbow trout (Oncorhynchus mykiss) which were raised in cage in Kemer Dam Lake built on Akçay River and pools located on the river between September, 2013 and August, 2014. The cage and pools are located between 37° 30' northern 28° 35' eastern longitudes, in Bozdoğan/Aydın, in western Turkey. One hundred fifty three (44%) fish were detected as positive various protozoans and metazoans at a total of 348 fishes. The number of cases and their percentages values in parenthesis in case of infection with one species are as follows: 118 (33.9%) T. fultoni, 19 (5.4%) I. multifiliis, 5 (1.4%) Apiosoma sp., 4 (1.1%) Lernaea sp. Seven of the 153 fishes (2%) were infected with mixed infection of T. fultoni + I. multifiliis (1.4%) and T. fultoni + Apiosoma sp. (0.6%). The logistic regression analysis was done in order to determine the effect share of the parameters which were supposed to have a role in the occurrence of the infection. The analyses indicated that the rate of infection in winter was 0.41 times less than it was in summer. An increase of one unite in water temperature result an 1.116 fold increase in infection odd ratio (OR), while 0.842 fold decrease was observed in response to one unite increase in dissolved oxygen amount (O2 mg/L). Likewise, an increase of one unite in fish length (cm), induced 0.88 fold decrease in infection odd ratio (OR), while an increase of one unite in fish weight (g) caused 0.99 fold reduction in infection odd ratio (OR). Consequently, high infection rate was detected as 44% and the dominant species among the parasites was observed as T. fultoni. Especially, when the water temperature increase; high stock density and contamination of water with feed residues/dead fish cause water quality to decrease. It was determined that such stress factors may be effective in increasing the prevalence of parasitic infections. [ABSTRACT FROM AUTHOR]

Artemia population was investigated monthly between November 2013-July 2014 in Tuz Lake and 5 stations were selected; one from the west side, 4 from the east side of the Lake. Some physical and chemical parameters (depth, secchi depth, water temperature, dissolved oxygen, conductivity and pH were measured monthly and ammonium nitrogen, nitrite nitrogen, nitrate nitrogen, orthophospate, alkalinity, total hardness, chlorophyll a, silicate concentrations were measured seasonally) of the Lake water were also determined. Artemia was found only once at the second sampling on March, in the 5th station in metanauplius form about 3,67x10³ individual.m, cycts were not found during the research. At the stations, chlorophyll a concentration (0.18-2.70 μg l-1) and orthophosphate concentration (0-1.07 mg l-1) values were found to be quite low, and ammonium nitrogen concentration values varied between 1.25 mg l-1 and 3.25 mg l-1. It is thought that Uluırmak and Peceneközü Brooks and DSİ Drainage Channel flowing into the basin of Tuz Lake affected the ammonium-nitrogen and orthophosphate concentrations in the Lake. The long-term investigations of the biological, physical and chemical properties of Tuz Lake will contribute to revealing the factors that caused to the present condition of the Lake. [ABSTRACT FROM AUTHOR]

The objective was to evaluate of groundwater quality for agricultural uses in the Lake Seyfe Basin, Turkey. For this, 20 different groundwater points were determined in the lake Seyfe Basin and water samples were taken from these points. The following 18 parameters were taken considered for evaluation: pH, electrical conductivity, temperature, sodium, potassium, calcium, magnesium, chloride, nitrite, nitrate, bicarbonate, ammonia, sulphate, dissolved oxygen, total hardness, total dissolved salts, percent of sodium and sodium adsorption ratio. Discriminant analysis was used to determine how the water quality parameters formed groups differ. As a results of the discriminant analysis were compared with guidelines based on various preceding guidelines developed and used in irrigated agriculture. In the study, the values of EC, Na, HCO3, NO3, NO2, TDS parameters were higher than the range of recommended guidelines for irrigation water quality. Further study of these parameters to examine is recommended. [ABSTRACT FROM AUTHOR]

Vertical and horizontal gradient of temperature, salinity, density, chlorophyll-a, dissolved oxygen and pH were monitored seasonally between summer 2008 and spring 2010 in the eastern, central and western basins of Izmit Bay (Marmara Sea). Surface seawater temperature ranged from 7.5 to 26 °C during the study period. Thermal stratification was found to be significant in winter and summer. Surface water salinity ranged from 20.9 to 24.0 × in summer 2008 and 2009 and reached up to 36.1 ? below halocline layer. Permanent pycnocline and a two-layered stratification were observed throughout the study. Sigma-t seasonally varied between 13.5 and 18.4 in the upper layer and increased up to 27.2 by increasing depth below the intermediate layer. Average seasonal Chl-a concentrations ranged from 1.5 in summer 2008 to 9.6 μg L-1 in spring 2010. The highest average Chl-a concentrations was found in the eastern basin during the study, whereas the maximum Chl-a level was measured as 18 μg L-1 in the central basin in spring 2010. Higher DO concentrations were measured in the western basin while the lowest (i.e., 0.2 mg L-1) was measured in the eastern basin located near the densely populated city center of the Kocaeli Province. Hypoxic conditions occurred in the intermediate layer in summer seasons while it was routinely present in the lower layer. Meteorological conditions impact the oceanography of the bay. In summer 2009, warm air temperature, weak wind speed, accordingly weak vertical water mixing accompanied with warm surface water resulted near surface hypoxia (i.e., below 4 m from the surface) in the eastern basin of Izmit Bay. [ABSTRACT FROM AUTHOR]

This paper presents the application of artificial neural networks (ANNs) and regression analysis (RA) for predicting dissolved oxygen concentrations (DO, mg/L) from water quality (WQ) indicators, namely stream water pH and temperature (t, °C). For this purpose, three diverse models are used in our analysis, considering the functional relationship between in situ-measured WQ indicators and DO concentration. The WQ data are semimonthly obtained from nine monitoring sites in the Harsit Stream watershed in the Eastern Black Sea Basin of Turkey, from March 2009 to February 2010. As a result of model prediction, this study proposes a suitable ANN model, including two independent variables to efficiently predict DO concentration from WQ data, with the root mean square error of 0.9442 mg/L and mean absolute error of 0.6965 mg/L. The proposed model predicts the DO concentration better than the RA and the other two ANN models. The results may reduce the time and cost necessary to determine DO concentrations. [ABSTRACT FROM AUTHOR]

A thorough investigation of the impact of rainbow trout ( Oncorhynchus mykiss) cultivation on surface water quality in the area known as Bereket HES IV Dam Lake was conducted. Water samples were collected from October 2009 to June 2010 from four stations in the Dam Lake and analyzed for water temperature, pH, dissolved oxygen, electrical conductivity, nitrite nitrogen, nitrate nitrogen, and orthophosphate. Surface water quality was then evaluated based on the comparison of samples collected from three stations located near fish cages to those collected from a reference station outside the cultivation area as well as by the comparison with standards specified in the Water Pollution Registration Act. According to the Water Pollution Registration Act, the surface water quality of the Dam Lake was class I. Additionally, there were no significant differences in water quality within the Dam Lake among any of the sampling stations, including the reference station. Overall, these findings indicate that cage cultivation of rainbow trout may have a negative impact on the entire Dam Lake. [ABSTRACT FROM AUTHOR]

This paper aims to reveal the reciprocal influence of Kürtün Dam and wastewaters from the settlements on the water quality in the stream Harşit, NE Turkey. Several key water-quality indicators were measured: water temperature ( T), pH, dissolved oxygen (DO), electrical conductivity, water hardness, chemical oxygen demand (COD), ammonium nitrogen (NH-N), nitrite nitrogen (NO-N), nitrate nitrogen (NO-N), total Kjeldahl nitrogen (TKN), total nitrogen (TN), orthophosphate phosphorus (PO-P), and methylene blue active substances (MBAS). The monitoring and sampling studies were conducted every 15 days from March 2009 to February 2010 at two stations selected in the upstream and downstream of the Kürtün Dam. It was concluded that the Kürtün Dam Lake had a high-quality water in terms of T, pH, DO, COD, NH-N, NO-N and NO-N values, but slightly polluted water with respect to TKN, PO-P, and MBAS according to the Turkish Water Pollution Control Regulation. The dam improved the stream water quality by increasing the DO concentration, and decreasing the NO-N and PO-P concentrations thanks to its hydraulic residence time despite the wastewater discharge by the nearby settlements. However, the wastewater discharge deteriorated the stream water quality increasing the COD, NH-N, NO-N, and TN concentrations. [ABSTRACT FROM AUTHOR]

Amik Plain is one of the most important agricultural areas of Turkey. Because the groundwater resources have been used not only for irrigation but also for drinking purpose, groundwater resources play a vital role in this area. However, there exist no or a very limited number of studies on groundwater quality and its physicochemical and heavy metal composition for Amik Plain. This study aimed to assess groundwater of Amik Plain in terms of human health and suitability for irrigation based on physicochemical variables, heavy metals, and their spatial distribution. A total of 92 groundwater samples were collected from wells and were analyzed for temperature (T), salt content (SC), dissolved oxygen (DO), ammonium (NH), nitrate (NO), and phosphorus (P) and such heavy metals as cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn). The temperature, SC, DO, NH, and NO parameters were measured in situ immediately with YSI Professional plus instrument (Pro Plus). Water depth was taken from owner of the wells. Heavy metal analyses were carried out in triplicate using inductively coupled atomic emission spectrometer (ICP-AES). The ICP-AES was calibrated for all the metals by running different concentrations of standard solutions. Descriptive statistical analyses were calculated to characterize distribution of physicochemical properties and heavy metal contents of groundwater. Correlation analysis was used to assess the possible relationships among heavy metals and physicochemical properties of the groundwater. Spatial variability in groundwater parameters were determined by geostatistical methods. Result shows that the highest and lowest coefficient of variation occurred for NO and T, respectively. Mean water table depth was 92.1 m, and only 12 of all the samples exceeded the desirable limit of 50 mg/L for NO content. The metal concentrations showed a dominance in the order of Fe > Mn > Ni > Cr > Cu > Zn > Co > Cd > Pb. All the samples had much higher Cd concentration than the guideline value for drinking water while Cu and Fe concentrations were below the guideline limit recommended by WHO. [ABSTRACT FROM AUTHOR]

The aim of the current study is to investigate the relationships between physico-chemical parameters, seasons, and fish size to determine levels of some heavy metals in water, sediment, and gills of Sander lucioperca in Karataş Lake, Turkey. Temperature, pH, dissolved oxygen, and EC (electrical conductivity) were measured. DORM 3 and DOLT 4 reference material showed good accuracy. In the water, Fe had the highest level, while Cd had the lowest. Generally, heavy metal levels increased in spring. Both positive and negative correlations were detected between their content in water and physico-chemical parameters. Results of the heavy metal levels were compared with national and international water quality guidelines. In sediment, Fe was the highest too. In fish, high levels of heavy metals were found in liver of pikeperch while low levels in muscle and gill samples depended on metal properties. In season, the metal levels were highest in autumn in muscle, in summer in liver, and in winter in gill. Positive and negative relationships were found between metal levels and fish size. Metal concentrations in the muscle of examined fish were compared with Turkish Food Codex and EC standarts. [ABSTRACT FROM AUTHOR]

Copyright of Adiyaman University Journal of Science & Technology / Adıyaman Üniversitesi Fen Bilimleri Dergisi is the property of Adiyaman University, Institute of Science / Adiyaman Universitesi Fen Bilimleri Enstitusu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Turkey is home to a large number of lakes, dam lakes and small lakes which have a great potential for growing fishery products. Growing trout in net frame systems manufactured in dam lakes is very common and economically very promising application. For growing trout, certain conditions such as certain water temperature range and minimum dissolved oxygen (DO) level must be satisfied. The water temperature required should be at 17-20 ºC to grow trout. Also, the amount of dissolved oxygen (DO) should never fall below 6-7 mg/L. As the temperature rises during the months of June-September, water temperature rises above the acceptable limits to grow trout. Producers usually use different types of internal combustion engine-pump (ICE-P) systems to provide the circulation of the colder water in the deeper parts of the lake to lake surface to grow trout in these months. But, this method is not economically feasible. In this study, as an alternative to ICE-P system, an axial flow deep well pump has been proposed for energy saving purposes. To validate the feasibility of the system, total of 40 net frame systems each has dimensions of 5x5x8 meters have been installed to grow trout in net frames in Lake Karacaören 2 in Burdur, Turkey. To grow trout in the hot seasons, it is necessary to circulate the colder water in the deeper parts of the lake to lake surface economically. For this aim, total of 10 an axial flow deep well pumps (AFDWPs) having a capacity of 300 m³/h, head of 4 m and running at 2850 rpm which is driven by 5.5 kW deep well motor (DWM) have been specially designed and manufactured. To compare the classical water circulation method with ICE-P and newly proposed AFDWP, after every two pumps (ICE/AFDWP) are installed, mean water temperatures were measured along the water column in net frame with the depth of 8 meters and also energy consumptions have been compared during the months of June to September. AFDWP and ICE-P were used only in these months where the water has to be circulated. According to the results energy consumption by using AFDWP was about 90 MWh/year, on the other hand, energy consumed by ICE-P was about 1949 MWh/year during the months of June-September. As a result, significant energy saving of 95.3 % (1906.8 MWh/year) can be obtained by using proposed AFDWP instead of the classical ICE-P during these months for total of 40 net frames. [ABSTRACT FROM AUTHOR]

Total of 40 ostracod taxa obtained from 141 different sampling locations in Bolu were examined to determine relationships between habitat preferences of species and their ecological characteristics from June to August 2006. According to the first axis of Canonical Correspondence Analysis (CCA), 52% of the relationships between species and five most influential environmental variables with 36.2% of variances were explained. Although the first four variables, air temperature, water temperature, pH, and electrical conductivity had significant influence ( P < 0.05) on species composition, the effect of dissolved oxygen ( P = 0.47) was relatively low. Spearman correlation analyses indicated that some species had weak to strong positive correlation with electrical conductivity, whereas some others had a significant negative correlation with pH and redox potential. Only two species ( Herpetocypris chevreuxi and Ilyocypris inermis) had strong correlation to the habitat type ( P < 0.05). Unweighted Pair-Group Method using Arithmetic averages (UPGMA) clustered species into four groups based on their occurrences. Species with cosmopolitan characteristics displayed higher tolerances to environmental variables than noncosmopolitans or rare species. Indeed, four cosmopolitan species ( Heterocypris incongruens, I. bradyi, Candona neglecta, and C. candida) had high Environmental Tolerance Index (ETI) values for at least six different environmental variables. Thus, cosmopolitans are highly adaptable within a wide range of environmental conditions and geographical distribution. [ABSTRACT FROM AUTHOR]

Diel dissolved oxygen (DO) measurements can be used to estimate water metabolism of aquatic systems, in particular, lakes, lagoons and streams in terms of gross primary production (GPP), ecosystem respiration (Reco) and net ecosystem production (NEP). One of the main assumptions in the calculation of lake metabolism is that Reco is the same for daytime (Rdaytime) and nighttime (Rdarkhr). This study aimed at testing the equal Rdaytime and Rdarkhr assumption to estimate GPP, Reco and NEP in a littoral zone of a temperate shallow lake (Lake Yeniçağa) in northwestern Turkey with and without the assumption. Based on the equal Rdarkhr and Rdaytime assumption, values calculated for GPP and Rdaytime were different than those based on the different Rdarkhr and Rdaytime assumption (P<0.001). GPP was lower by 7.5% in July, 49.6% in September and 14.9% in October, while Reco was lower by 5.9% in July and 55.8% in September. GPP was higher by 8.9% in August and 55% in November, while Reco was higher by 7.8% in August and 23.9% in November. [ABSTRACT FROM PUBLISHER]

Abstract: In this study, trends in selected water quality parameters in Eymir Lake over a period of 10years are analyzed using the Mann–Kendall test. Analyzed water quality parameters are dissolved oxygen (DO), total phosphorus (TP), total suspended solids (TSS), and secchi depth (SD). In addition, trends in the yearly averages of precipitation, lake volume, and ambient temperature are examined. According to Mann–Kendall test results, precipitation, volume and ambient temperature values exhibit decreasing trends in 1998–2008. DO and TSS exhibit increasing trends while TP and SD have decreasing trends in Eymir Lake. The change in the volume of the lake has a significant impact on the trends of DO, TSS, and SD. These results indicate that, besides eutrophic conditions, water balance and drought conditions significantly impact the water quality of Eymir Lake. [Copyright &y& Elsevier]

The Permian-Triassic Boundary sequence at Çürük Dag, near Antalya, Turkey, begins with a major erosion surface interpreted as being the Late Permian lowstand, on which lies ca 0·4 m of grainstone/packstone composed of ooids, peloids and bioclasts. Most ooids are superficial coats on fragments of calcite crystals presumed to be eroded from crystal fans which are no longer present. The erosion surface is smooth and shows no evidence of dissolution; the grainstone/packstone contains intraclasts of the underlying wackestone, proving erosion. Next are 15 m of microbialite comprised of interbedded stromatolites, thrombolites, plus beds of planar limestones with small-scale erosion. The latter comprise a complex interlayering of stromatolitic, thrombolitic and peloidal fabrics and precipitated crystal fans, which form a hybrid of microbialite and inorganic carbonate, together with bioclastic debris and micrite. The Çürük Dag microbialite sequence is repetitious; the lower part is more complex, with abundant stromatolites and hybrid microbialites. Some of the stromatolites are themselves hybrids composed of peloids and crystal fans. In the upper part of the sequence stromatolites are missing and the rock is composed mostly of recrystallized thrombolites that develop upwards from tabular to domal form. The domes form directly below small breaks in microbialite growth where very thin shelly micrites and grainstones/packstones are deposited. Repetition of facies may be controlled by sea-level change; a deepening-up model is consistent with the evidence. Stromatolites (with abundant crystal fans) dominate in shallower water, deepening through hybrid microbialite and interlayered sediments to thrombolite, probably no more than a few tens of metres deep, followed by breaks and renewal of microbialite growth. An interpretation of open marine fully oxygenated waters for microbialite growth is consistent with ongoing parallel work that has identified Bairdioid ostracods in the microbialite, a group known to be open marine. However, other researchers have proposed low oxygen conditions for Permian-Triassic boundary facies globally, so work continues to confirm whether the Çürük Dag microbialite grew in dysoxic or normally oxygenated conditions. The principal stimulus for post-extinction microbialites is likely to be carbonate supersaturation of the oceans. The microbialite sequence is overlain by a further 25 m of grainstone/packstone (without microbialite), followed by Early Triassic shales. Overall, microbialites form a thin aggradational sequence during an overall relative sea-level rise, consistent with global eustatic rise following the Late Permian lowstand. [ABSTRACT FROM AUTHOR]

Copyright of Journal of the Institute of Science & Technology of Dumlupinar University / Dumlupinar Üniversitesi Fen Bilimleri Enstitüsü Dergisi is the property of Dumlupinar University, Institute of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Data-driven models are commonly used in a wide range of disciplines, including environmental engineering. To analyze Omerli Lake’s historic water pollution status, this study monitors data for dissolved oxygen, 5-day biochemical oxygen demand, ammonium nitrogen, nitrite nitrogen, nitrate nitrogen, and ortho phosphate. The quality of the lake water is assessed based on measurements of dissolved oxygen. The collected data are analyzed using regression analysis and artificial neural network models. The main goal of this paper is to reveal the best applicable data-driven model in order to gain forward-looking information regarding the dissolved oxygen level of the lake using other pollution parameters. In order to ascertain eutrophic status, total phosphorus loads for each year are represented on a Vollenweider diagram. Results designate an increasing risk of eutrophication for Omerli Lake in recent years. Results of the data-driven models show that the artificial neural networks model constitutes the best relationship between the dissolved oxygen and other parameters. [ABSTRACT FROM AUTHOR]

The study comprised modification of the Canadian Council of Ministers of the Environment (CCME) Water Quality Index (CCMEWQI) to obtain a tool in classification of surface waters according to quality defined by the European Legislation—75/440/EEC. Three categories were proposed, and the category ranges of CCMEWQI have been modified depending on the objective chosen. The application of the CCMEWQI with modified categorization scheme was demonstrated to assess overall water quality by integrating observed water quality determinants in the Kucuk Menderes Basin, Turkey. In this scope, the samples analyzed for pH, total dissolved solids (TDS), chlorides (Cl), nitrate–nitrogen (NO3–N), dissolved oxygen (DO), biochemical oxygen demand (BOD5), sulfate (SO4), and boron (B), variables taken monthly over 2 years from the five monitoring sites, were processed. Results revealed that the overall surface water mainly fell within the A2 water class. The CCMEWQI with modified categorization scheme is believed to assist water managers to integrate and interpret the picture of overall water quality based on the European legislation concerning the quality required of surface water intended for the abstraction of drinking water in the Member States (75/440/EEC). [ABSTRACT FROM AUTHOR]

In this study, surface water quality of the Ceyhan River basin were assessed and examined with 13 physico-chemical parameters in 31 stations in 3 months during the period of 2005. Multivariate statistical techniques were applied to identify characteristics of the water quality in the studied stations. Nutrients, Cl − and Na + affected mostly to the stations of Erkenez 2, Sır 2, and Sır 3 in the ordination diagram of correspondence analysis. Three factors were extracted by principal component analysis, which explains 79.14% of the total variation. The first factor (PC1) captures variables of EC, DO, NO $_{2}^{\; -}$, PO $_{4}^{\; \equiv }$, Cl − , SO $_{4}^{\; =}$, Na + , and Ca + + . The second factor (PC2) is significantly related to pH, NH $_{3}^{\; -}$, and Mg + + , while water temperature ( T) and NO $_{3}^{\; -}$ accounted for the greatest loading for factor 3 (PC3). The stations were divided into three groups for PC1, two groups for PC2, and three groups for PC3 by hierarchical cluster analysis. The stations in the vicinity of cities presented low dissolved oxygen and high concentration of physico-chemical parameter levels. The stations of Erkenez 2, Sır 2, Sır 3, and Aksu 4 located near the city of Kahramanmaraş were characterized by an extremely high pollution due to discharge of wastewater from industry and domestic. Pınarbaşı and Elbistan stations were also influenced by household wastewater of the city of Elbistan. According to criteria of Turkish Water Pollution Control Regulation, Erkenez 2, Sır 2, and Sır 3 stations have high polluted water. This study suggests that it is urgent to control point pollutions, and all wastewater should be purified before discharge to the Ceyhan River basin. [ABSTRACT FROM AUTHOR]

Copyright of Review of Hydrobiology is the property of NK Yayincilik Egitim Hizmetleri and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Review of Hydrobiology is the property of NK Yayincilik Egitim Hizmetleri and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Review of Hydrobiology is the property of NK Yayincilik Egitim Hizmetleri and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Review of Hydrobiology is the property of NK Yayincilik Egitim Hizmetleri and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Omerli reservoir is located on the northeastern side of the Istanbul City. It is one of the most important sources of drinking water with a surface area of 23.1 km2 and a volume of 220 × 106 m3 in the Marmara Region. Water quality characteristics of the lake investigated from May 2002 to April 2003 enabled us to identify the effect of waste loads on water quality of Omerli Lake. The following parameters were measured in the lake water: temperature (16.1°C), conductivity (250 μS/cm), secchi disk depth (1.9 m), dissolved oxygen (DO) (9.36 mg/L), nutrients [ortho-phosphate (78.9 μg/L), nitrate + nitrite (707.5 μg/L) and ammonia-nitrogen (264 μg/L)], chlorophyll a (9.43 μg/L), total organic carbon (3.33 mg/L), total suspended solids (4.54 mg/L), total poly aromatic hydrocarbon (t-PAH) (0.69 μg/L) and copper (24.5 μg/L). T-PAH (16.5 mg/g-dry-w), Cu (96.5 μg/g-dry-w), organic carbon (org-C) (2.0%) and N (0.44%) were determined in the surface sediment. The values of chlorophyll a and DO in the upper layer were relatively high and low secchi disk depths indicates eutrophic state. There are five channels discharging water, including waste water, into the lake. All channels were sampled during six occasions in order to cover variations between seasons. The following parameters were measured: total organic carbon, total phosphorus, total kjeldahl nitrogen, ammonia and total suspended solids with the flow rates. The Göçbeyli stream has the highest flow into the lake (1.5 × 108 m3/year) but most of the nutrients were discharged from the Paşaköy channel. It is accounting for 81% of ammonia and 80% of total phosphorus into the lake. Three scenarios were run using AQUATOX model: (1) all existing inflows are discharging into the lake (present situation); (2) none is discharging; (3) all are discharging except the Paşaköy channel. The first scenario produced concentrations consistent with measurements in the lake. In all stations, a phytoplankton peak value was predicted during November and December 2002, and January 2003. In the second scenario, as expected, a significant decrease in the concentrations was predicted. In the third scenario, a small improvement in the water quality was obtained. To significantly improve the state of the lake, instead of entering Paşaköy channel, wastewater should bypass the lake. [ABSTRACT FROM AUTHOR]

The QUAL2E model was applied to the Büyüksu Stream, Bolu, Turkey, to predict the effect of conventional and industrial pollutant sources on stream quality. The model parameters were conditioned using data from eight sampling stations on a 24-km stretch of the stream during a steady-state period between May 2003 and June 2004. The higher biochemical oxygen demand (>50 mg/L) and lower dissolved oxygen concentrations measured (<4.0 mg/L), with their expected values, indicated that the water quality of the Buyuksu Stream was threatened by industrial and domestic pollution. The oxygen-sag curves obtained by the model calculations proved that discharges of the Bolu City wastewater and wood- processing plant effluent were the two primary pollutant sources affecting the stream. Results suggested that the conditioned model can be used as a tool to show the effects of pollutant sources on the Büyüksu Stream and to assess improvements expected by reducing the contribution of pollutant sources. Water Environ. Res., 81, 325 (2009). [ABSTRACT FROM AUTHOR]

Different sources of pollution in Karasu Creek were investigated to obtain the water quality and ratio of contamination in this region. To achieve the main objectives of the present study, water samples were collected from Karasu Creek, starting from flow pattern at the upstream site of Akkaya Dam to the end of the dam, crossing the place where the Creek drains into. Dissolved oxygen, electrical conductivity, temperature and maximum/minimum pH were measured systematically for 12 months in the stations, where the water samples were collected. Chemical analyses of the water samples were carried out by using Cadas 50 S brand UV spectrometer to find out the Pb, Fe, Cu, Zn, Ni, Cr, Cd, S, F and Cn concentrations. These concentration were determined in μg/lt as 80–850; 180–4,920; 10–6,100; 440–25,530; 130–2,400; 120–280; 20–150; 214,250–1,113,580; 1,560–4,270 and 40–690, respectively. To determine metal levels of the water samples, multivariate analyses (element coefficient correlation, coefficient correlation dendrogram, hierarchical cluster analysis dendrogram, model summary and ANOVA) were used. The analyses yielded highly accurate results. There were positive correlations between some elements and their possible sources were the same. The stations which resembled each other along the creek were divided into three groups. The water quality of the creek was low and had toxic qualities. Eutrophication developed in Akkaya Dam along the creek. The source of pollution was thought to be industrial and residential wastes. Absolute (0–100 m), short distance (100–500 m) and medium distance (500–2,000 m) conservation areas should be determined in pollution areas along Karasu Creek and they should be improved. [ABSTRACT FROM AUTHOR]

Clathrocorys teuscheri is one of the Polycystine radiolarins. It is reported for the first time in the north-eastern Aegean Sea by this study. As this species was previously reported from the sapropel as microfossils in the eastern Mediterranean, it is also first record for Mediterranean recent plankton. The specimen was collected in November 2000 from subsurface (0.5 m) coastal waters with a depth of 30 m, near Bozcaada Island in the Aegean Sea. Primary hydrographic conditions such as salinity (36.0 psu), temperature (16.7 °C) and dissolved oxygen (9.49 mg l-1) were recorded at the sampling station. [ABSTRACT FROM AUTHOR]

The Izmit Bay is an elongated semi-enclosed bay in the Marmara Sea. It is being increasingly polluted by both domestic and industrial waste discharge since 1970’s. A monitoring program was conducted between 1999-2000 to document the state of pollution in the bay. This includes the effect of Marmara (Izmit) earthquake (magnitude 7.4) that occurred in August 1999. A stable two-layer ecosystem exists in the bay throughout the year due to continuous inflows of the saltier Mediterranean and brackish Black Sea waters to the Marmara basin. Therefore, the principal biochemical characteristics of the bay are governed by the two-layer flow system over the basin. Dissolved oxygen (DO) is generally at a saturated levels in the surface layer which is 10 to 15 m thick, but it is depleted to 60–70 µM in the lower layer, exhibiting a steep gradient in the sharp halocline. When the earthquake occurred, great loads of industrial wastes were released into the bay surface waters, which enhanced primary production in the upper layer and thus large export of particulate organic matter to lower layer and eventually to the bottom. Accordingly, DO was consumed and anoxic condition was established even in the upper layer/halocline interface, the halocline and bottom waters of the eastern and central bay. In this period, concurrent increases were observed in phosphate and ammonia contents at the halocline and in deep waters whilst the nitrate was almost consumed via denitrification processes in the anoxic water. Recently, the industrial C, N and P loads increased by as much as 8 fold within five years (1995–2000) whilst domestic inputs increased by 50%. Total organic matter discharged to the bay increased more than double within the last 15 years. Besides, most factories in the region release toxic wastes into the bay after only partial treatment. [ABSTRACT FROM AUTHOR]

The effects of marine aquaculture on the environment were evaluated by studying the water quality of Güllük Bay (Turkey). Marine aquaculture, both extensive and intensive, is one of the most important activities carried out in this area. The intensive culture of fish (Dicentrarchus labrax) is the most important polluting element in Güllük Bay. Records of long term (seasonally) monitoring of the ambient water dissolved oxygen concentration, the inorganic nutrients (ammonia, nitrate, nitrite, and phosphate) and chlorophyll a concentrations were generated to assess sea water quality of Güllük Bay. Surface water (0.5 m) samples were collected from seven fish farm areas in the cage of Güllük Bay (here after reported as the cage stations). Reference surface water was also concurrently sampled at three stations. Modifications in the cage stations water quality were assessed as the difference between the magnitude of a specific parameter recorded at cage station and the concurrently recorded value of the parameter at the reference station, relative to the mean value at the reference station. In this study, results in the specific modifications are discussed at the study period. An aquaculture area had consistently positive modifications in phosphate concentration, but not in nitrogen or chlorophyll a concentrations. Chlorophyll a concentrations showed non positive modifications only in June. In addition to these site specific modifications nitrogen concentrations were positively modified in August and October. [ABSTRACT FROM AUTHOR]

• Water Quality Index (WQI) was used to determine the water quality of the stream. • Hazard quotient (HQ) and hazard index (HI) was used for the evaluation of trace elements in terms of public health risk. • Turnasuyu Stream has a very good water quality characteristic. • The trace elements identified were not in dangerous limits for public health. • Turnasuyu Stream has an oligotrophic structure with low chlorophyll a levels. The effect of agricultural activities and domestic pollution on water quality in the Turnasuyu Basin was evaluated. Sampling was performed during the period of a hydrological year (February 2017–January 2018) in the surface water on the selected three sampling points to represent the upstream, midstream and downstream basin of the Turnasuyu Stream. General conditions of water quality parameters (temperature, pH, conductivity, total dissolved solids, suspended solids, turbidity, salinity, oxidation reduction potential, alkalinity, total hardness), oxygenation parameters (dissolved oxygen, oxygen saturation, biological oxygen demand), nutrient parameters (ammonium-N, nitrite-N, nitrate-N, total phosphate, total phosphorus), trace elements, inorganic pollution parameters and suspended chlorophyll a content from biological parameters were examined. Analyzes were performed using standard methods. Multiple statistical methods such as principal component analysis (PCA), Pearson correlation index (PCI) and clustering analysis (CA) were applied to the results. Water Quality Index (WQI) was used to determine the water quality of the stream and hazard quotient (HQ) and hazard index (HI) was used for the evaluation of trace elements in terms of public health risk. The results showed that the Turnasuyu Stream has a very good water quality characteristic, and that the trace elements identified were not in dangerous limits for public health. Turnasuyu Stream has an oligotrophic structure with low Chlorophyll a levels. [ABSTRACT FROM AUTHOR]

The hydrogeochemistry of geothermal waters from 31 geothermal fields in eastern Turkey is investigated with regard to major ion compositions, stable (δ18O-δ2H-δ34S) and tritium (3H) isotope systematics. Discharge temperature of studied waters varies from 24 to 65 °C. Four different geochemical processes were found to control the major ion concentrations of waters which include dissolution of carbonates, fluid-mineral interaction, oxidation of sulfur-bearing minerals, and chloride enrichment. The northern, central and southern provinces are represented by different local meteoric water lines (LMWL) with deuterium excess of 15.0, 13.9 and 16.5‰ V-SMOW, respectively. The stable isotope values of the thermal waters are close to LMWLs and indicate a meteoric origin. The enrichment in oxygen isotope composition (0.6 to 7.7‰ V-SMOW) in some thermal waters resulted from water–rock interaction process and 18O-exchange process between CO 2 and H 2 O. The δ34S and δ18O contents in dissolved sulfate cover a wide range from 6.2 to 32‰ V-CDT and from −2.5 to 14.8‰ V-SMOW, respectively, indicating that the sulfate isotope systematics of the majority of waters is governed by dissolution of terrestrial sulfate and marine evaporites. The reservoir temperatures estimated by chemical and isotopic geothermometers of K Mg (27–127 °C), silica (29–179 °C) and 18O SO4-H2O (51–196 °C), and by the silica-enthalpy mixing model (130 to 235 °C) yielded inconsistent results. The geological factors (e.g., relatively thick crust, low surface heat flux, absence of ideal cover units) in eastern Turkey have resulted in the development of low- or moderate-temperature geothermal systems. • Eastern Turkey hosts low- or moderate-temperature geothermal systems. • Carbonate dissolution and fluid-mineral reactions control the water chemistry. • High crustal thickness and low surface heat flux control temperature of waters. [ABSTRACT FROM AUTHOR]