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    Comprehensive risk assessment of metals in surface sediments of the Southern Black Sea coastal and transition waters
    (Elsevier, 2024) Bat, Levent; Sahin, Fatih; Oztekin, Aysah; Ozsandikci, Ugur; Ozkan, Ebru Yesim
    This study was carried out to determine metal levels accumulated in the sediments collected from the transitional and coastal waters of the southern Black Sea. Samples were taken from 32 stations in May and September 2018. The concentrations of elements were measured by an Inductively Coupled Plasma Mass Spectrophotometer (ICPMS). Enrichment Factor (EF), Geo -accumulation Index (Igeo), Pollution Load Index (PLI), Contamination Factor (C f ), and Modified Degree of Contamination (mC d ) were applied to the data for assessing the sediment quality. Associations between the variables were also revealed by factor analysis. Igeo of metals are obtained in coastal sediments only when Hg in May and Cr in September are classified as moderately polluted. PLIs exceeded one at stations in the industrial zone, indicating getting worse. It is necessary to prevent pollution from industrial, domestic, and agricultural sources and to control agricultural lands.
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    Öğe
    Effects of biogeochemical processes on spatial distribution of iron, manganese, reactive phosphates and nitrates in the Black Sea
    (Natl Inst Science Communication-Niscair, 2019) Ozkan, Ebru Yesim; Buyukisik, Baha; Bat, Levent
    The aim of this study was to identify differences in the distribution of Mn (Manganese), Fe (Iron), NO3- (Nitrates) and reactive phosphates (RP) in the water columns of the eastern and western basin of the Black Sea region. Accordingly, the selected sampling area covered offshore waters from west to east including Istanbul (station KD01), Eregli (KD2A, 2B, and 2C), Inebolu (KD03), Sinop (KD04), Ordu (KD5A, 5B, 5C) and Trabzon (KD06). The B and C codes for stations 2 and 5 indicate that the stations are towards the basin centers of the Black Sea. At all the stations of the study area, the Mn values were below the limit of detection (5 mu g/L) up to 100 m depth. The Mn concentration reached maximum at 200 m depth of stations KD2B, KD5B, KD5C and KD06. This situation could be due to mobilization of Mn from the continental slope sediments (Mn pump). Also, it was observed that relatively high values of nitrates were associated with low RP concentration in the deep waters of the eastern basin. If nitrate is present in the suboxic zone, bacteria prefers nitrate and reduce it as N-2 (g). Then, the FeOOH=RP (ferric oxyhydroxides equivalent to reactive phosphate) particulates sink into deeper layers without reduction by bacteria and cause the upper layers to become poor in phosphates. In case of low values of nitrate in suboxic zone, FeOOH equivalent to RP particulates are reduced to dissolved Fe+2 by the bacteria. Significantly higher levels of nitrate concentrations were observed at station KD06. In conclusion, the eastern basin center is characterized by relatively higher nitrate concentrations in water columns compared to those in the western basin center. Therefore, the eastern basin contains lower RP concentrations and this limits the phytoplankton growth. It is concluded that where nitrate concentrations are higher than 2 mu M, the bacteria preferred to reduce the nitrates. On the other hand, particulate Fe can be reduced chemically with H2S in the deeper layers, where there is lower nitrate concentration.
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    Öğe
    Heavy Metal Levels in Sediment of the Turkish Black Sea Coast
    (Igi Global, 2019) Bat, Levent; Ozkan, Ebru Yesim
    Sediments are an important repository for various pollutants such as pesticides and heavy metals and also play a significant role as sensitive indicators for monitoring contaminants in aquatic systems. Heavy metals which are regarded as serious pollutants of aquatic ecosystems are a major environmental problem in the Black Sea. Contamination by heavy metals has not been extensively studied in the Black Sea coast of Turkey, even though these are subjected to intense discharges of pollutants. It is important, therefore, that sediment by heavy metals be assessed in order to facilitate better management and protection of these valuable coastal ecosystems. This is especially the case, since Turkish Black Sea coast represents a prominent area for fishing, industrial development and urban extension and tourism activities. In view of the economic importance of the Black Sea coastal region of Turkey, this review aims to analyses the distribution and concentrations of heavy metals in bottom sediment in the coastal sediment along the Black Sea.
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    Öğe
    Spatial geochemical structure of soft sediment on shallow littoral of the Gulf of Antalya, the eastern Mediterranean Sea
    (Pergamon-Elsevier Science Ltd, 2023) Yalcin, Mustafa Gurhan; Mutlu, Erhan; Olguner, Cansu; Atakoglu, Ozge Ozer; Bat, Levent; Ozkan, Ebru Yesim
    The concentrations of heavy metals in soft sediments of the Manavgat and Lara regions in Antalya, Turkiye were investigated to assess contamination levels and their potential sources, followed by multivariate statistical analysis and generation of spatial distribution maps. Results showed low contamination levels for As, Zn, and Cu, moderate contamination for Pb, Ni, and Mn, and very high accumulation for Co and Cr. Geoaccumulation index (Igeo) and contamination factor (CF) analyses revealed moderate enrichment for Mn and low enrichment for As, indicating no human-induced contamination in Cu, Pb, Zn, Mn, and As, while Ni, Co, and Cr originated mainly from agriculture. The maximum modified degree of contamination (mCd) value was at an extreme high level, with an average mCd of 4.12 indicating high contamination. Maximum pollution load index (PLI) value was 3.13, indicating high-grade pollution and an average value of 1.7 indicating moderate pollution.