Southern Black Sea Region Research Articles

Revisiting the depositional age and provenance characteristics of metasedimentary rocks from the basement units in the Central Pontides (N Turkey): New constraints for tectonic evolution of the southern Black Sea region

The pre-Jurassic tectonic evolution of the Central Pontides in northern Turkey is still poorly understood due to the lack of detailed geochemical and geochronological data from the basement units. Therefore, this study reports for the first time combined whole rock geochemistry, trace element data and U-Pb ages for detrital zircons, and Ar-Ar geochronological data from the metasedimentary rocks of the Devrekani Massif, Geme Complex, and the Serveçay Unit to better understand their provenance, depositional age characteristics, and tectonic evolutions. The detrital zircon U-Pb data of metasedimentary units from the Devrekani Massif, Geme Complex, and the Serveçay Unit yield ca. 191, 185 and 298 Ma maximum depositional ages (youngest age peaks), respectively. The Devrekani Massif is dominated by Permo-Carboniferous-aged detrital zircons (67 %), whereas Neoproterozoic and Devonian-aged detrital zircons are more common in the Geme Complex (47 %) and the Serveçay Unit (53 %). These distinct age distributions clearly indicate that the Devrekani Massif may has been deposited in a dissimilar location compared to the Geme Complex and the Serveçay Unit. Furthermore, in contrast to the Devrekani Massif, the source area of the metasedimentary rocks from the Geme Complex is comparable with that of the Serveçay Unit. Lastly, the obtained detrital zircon U-Pb and mica Ar-Ar ages suggest that the Devrekani Massif and the Geme Complex were deposited and metamorphosed during the Early and Middle Jurassic, respectively. The Serveçay Unit was deposited and metamorphosed in the Permian.

Temporal change of potential toxic element contamination, ecological and toxicological risk in holocene in Southern Black Sea coasts (Türkiye)

This study was carried out to evaluate the temporal variation of the potential toxic element concentration and ecological risk level during the Holocene along the Southern Black Sea coasts. Ecological and ecotoxicological indices such as enrichment factor (EF), modified ecological risk index (mRI), modified potential ecological risk index (mPER) and toxic risk index (TRI) were used in the study. Anthropogenic effects were determined to be more dominant in the western and middle parts of the Southern Black Sea Region. As, Cu, Pb, Zn, Cd, Hg, Ni enrichments were observed in the last 200 – 300 years and the potential risk index values related to them increased. Source of enrichment detected in the cores was found to be related to the volcanic activities that occurred in different geological periods. It was determined that the increases in PTE concentration observed specifically in the middle parts of the cores coincided with the dates of the volcanic activities observed in Anatolia.

Metal concentrations, selenium-mercury balance, and potential health risk assessment for consumer of whiting (Merlangius merlangus euxinus L., 1758) from different regions of the southern Black Sea.

The significant increase in the human population and the associated industrial wastes have a widespread impact on coastal areas. It is important to monitor trace elements that affect food safety and pose a potential consumer health threat. All over the Black Sea coast, people enjoy consuming whiting as both meat and roe. In February 2021, whitings were caught by bottom trawling from four different locations on the coasts of Kastamonu, Sinop (Sarıkum, Adabaşı), and Samsun in the southern Black Sea region. The meat and roe extracts obtained from whiting samples were analyzed through an optical emission spectrophotometer (ICP-MS). Trace element concentrations of whiting meat and roe in this study were Zn > Fe > Sr > As > Al > Se > B > Mn > Cu > Hg > Li > Ni > Ba > Pb > Cr > Cd and Zn > Fe > Al > As > Cu > Sr > Mn > Se > B > Ba > Li > Ni > Hg > Cr > Pb > Cd, respectively. These amounts were lower than the acceptable values accepted by the EU Commission. In case of whiting and roe consumption of a maximum of three portions (860.33g) for Adabaşı, six portions for Kastamonu (1432.37g), three portions for Samsun (828.55g), and five portions (1253.04g) for Sarıkum per month do not pose a health risk.

The Trade Centers Of The Southern Black Sea Region And The International Trade Relations Of Azerbaijan Before The Ottoman Invasion

Till the 1450s, the Ottoman Empire had no serious influence on the Black Sea coast yet. The Republics of Genoa and Venice, special trade colonies of on the shores of the Black Sea, were more active in commercial activities. The main trade Genoaese colony was the city of Kaffa, located in the Crimea. In the middle of the 15th century, European merchants tried to buy raw silk, imported from Azerbaijan, in the main trading centers of Genoa, Constantinople, and the Southern Black Sea region. The raw silk, imported from Gilan, Astrabad, Lahijan and Mazandaran, was bought by European merchants as a high-quality raw material in the listed trading centers. In the second half of the 15th century, the advance of the Ottoman empire to the west and the subsequent conquest of important trade centers in the Black Sea, Mediterranean and Aegean seas, where they traded with European countries, dealt a blow to the silk trade of Azerbaijan.

Age, Growth, Reproduction and Fecundity of the Sharpsnout Seabream (Diplodus puntazzo Walbaum, 1792) in the Black Sea Region

In this study, the Sharpsnout Seabream (Diplodus puntazzo) population parameters (age, sex composition, length-weight relationship (LWR), age-length relationship, growth parameters, condition factor, gonadosomatic index, reproductive) of the sharpsnout seabream (Diplodus puntazzo) in the southern Black Sea Region have been investigated. In the study carried out between April 2018 and March 2019, 276 sharpsnout seabream were sampled and the average length and weight were calculated as 30.0 cm and 463.9 g, respectively. Male and female ratio was determined as 1:1.32 (P>0.05). Age of fish varied between 0-9 years. The von Bertalanffy growth parameters were L∞=48.1 cm, k=0.2656 year-1 and t0=-1.6587 year for all individuals. The LWR was found as W=0.0399 L2.7212 for all individuals. Total mortality rate (Z=0.560), natural mortality rate (M=0.501) and fishing mortality rate (F=0.059), growth performance index (φ'=2.73) and condition factor value (K=1.55) were calculated. The maximum GSI value was 6.83 in September. Mean relative fecundity was calculated as 14695.4 eggs / 1g. The mean egg diameter was calculated as 486.83µm. This study is very important in terms of being the first study on this species in the Black Sea and will provide a source for future studies.

Dynamics of the number of grape thrips (Drepanothrips reuteri Uzel.) in grape agrocenoses of the Southern Black Sea region of Ukraine

Goal. To study population dynamics of grape thrips (Drepanothrips reuteri Uzel.) and determine the factors influencing the increase in the number and harmfulness in grape agrocenoses of the southern Black Sea region of Ukraine.
 Methods. Field surveys of vine plantations and counts of the number of pests were carried out according to generally accepted methods during 2017—2020 in conditions of research farms SE «EF Suvorov’s» and SE «EF Tairove» NSC «V.Ye. Tairov Institute of Viticulture and Winemaking».
 Results. It was found that in the conditions of the southern Black Sea zone of Ukraine there is an increase in the species composition and area of sucking phytophages in grape agrocenoses, especially some species of thrips. Among herbivorous thrips, species characteristic of this zone grape (Drepanothrips reuteri Uzel.) and tobacco (Thrips tabaci Lind.), several more harmful species appeared: variegated (Frankliniella intonsa Trybom), yellow (Thrips flavus Schrank), nightshade (Thrips fuscipennis Haliday), pear (Taeniothrips inconsequens Usel) and greenhouse (Heliothrips haemorrhoidalis Bouche). The number of thrips on grape leaves during the growing season is low — 0.3—4.8 motile individuals per 100 cm2 of leaf surface (corresponding to one average leaf), but the difference between susceptible and tolerant varieties can be traced even with a small presence of thrips. The highest degree of infestation and leaf damage was recorded in grape varieties without pubescence or with weakly pubescending leaves.
 Conclusions. Based on the results of the long-term (2017—2020) monitoring of the phytosanitary state of industrial grape plantations in the southern Black Sea region, it has been established that Thrips (Thysanoptera) occupy an important place among pests, the most common are grape thrips (Drepanothrips reuteri Uzel.), The mass development of which occurs every year during the flowering period of grapes. Research has established that the varietal composition of grape plantations and features climatic conditions of the southern Black Sea coast of Ukraine are favorable for overwintering, development, distribution and accumulation of numbers grape thrips and other sucking pests. It makes you spend constant monitoring, determination of biophenology in order to develop effective methods of regulating their quantity and harmfulness.

Geochemical characteristics of the adakite-like Dodurga Pluton (Central Pontides, N Turkey): implications for Middle Triassic continental arc magmatism in southern Black Sea region

The tracing of Triassic arc magmatism is much-debated for a long time along the Sakarya Composite Terrane in Turkey and the southern Black Sea region. The Dodurga Pluton is located in the Central Pontides (N Turkey), one of the most complicated regions around the Black Sea region, and represents the first documented middle Triassic continental arc in the region. This pluton comprises of dacite porphyry and granodiorite, and displays calc-alkaline signatures, which is in agreement with arc-related and I-type magmas. The PM-normalized multi element and CN-normalized REE patterns are akin to volcanic arc granites, and characterized by LILEs and LREEs enrichments relative to HFSEs and HREEs coupled with negative Nb anomalies, which confirm derivation in a subduction-related tectonic setting. Moreover, the major and trace element systematics of the samples including higher Sr/Y ratios (22.93–101.36) and lower Yb contents (0.31–1.30 ppm) are consistent with those from adakitic melts compared to classical arc magmas. Therefore, this pluton also represents the first middle Triassic adakite-like magmatic occurrence in Turkey. Overall petrographic and geochemical signatures reported here indicate that the Dodurga Pluton might have been derived from a heterogeneous source, mixed by melts from subducted oceanic slab and lower continental crust in an active continental margin. Based on the Tethyan evolution in the Anatolian realm, three geodynamic scenarios are possible for its formation, and it could have been formed as a result of northward or southward-subduction of the Paleotethys Ocean or northward-subduction of the northern branch of Neotethys Ocean during the middle Triassic.

Город Птерия у Геродота и некоторые аспекты истории греческих полисов южного Причерноморья

Город Птерия у Геродота и некоторые аспекты истории греческих полисов южного Причерноморья

Vegetation and environmental dynamics in the southern Black Sea region since 18 kyr BP derived from the marine core 22-GC3

Sediments from the Black Sea, a region historically dominated by forests and steppe landscapes, are a valuable source of detailed information on the changes in regional terrestrial and aquatic environments at decadal to millennial scales. Here we present multi-proxy environmental records (pollen, dinoflagellate cysts, Ca, Ti and oxygen isotope data) from the uppermost 305cm of the core 22-GC3 (42°13.53′N, 36°29.55′E) collected from a water depth of 838m in the southern part of the Black Sea in 2007. The records span the last ~18kyr (all ages are given in cal kyr BP). The pollen data reveal the dominance of the Artemisia-steppe in the region, suggesting rather dry/cold environments ~18–14.5kyr BP. Warming/humidity increase during melt-water pulses (~16.1–14.5kyr BP), indicated by δ18O records from the 22-GC3 core sediment and from the Sofular Cave stalagmite, is expressed in more negative δ13C values from the Sofular Cave, usually interpreted as the spreading of C3 plants. The records representing the interstadial complex (~14.5–12.9kyr BP) show an increase in temperature and moisture, indicated by forest development, increased primary productivity and reduced surface run-off, whereas the switch from primary terrigenous to primary authigenic Ca origin occurs ~500yr later. The Younger Dryas cooling is clearly demonstrated by more negative δ13C values from the Sofular Cave and a reduction of pines. The early Holocene (11.7–8.5kyr BP) interval reveals relatively dry conditions compared to the mostly moist and warm middle Holocene (8.5–5kyr BP), which is characterized by the establishment of the species-rich warm mixed and temperate deciduous forests in the low elevation belt, temperate deciduous beech-hornbeam forests in the middle and cool conifer forest in upper mountain belt. The border between the early and middle Holocene in the vegetation records coincides with the opening of the Mediterranean corridor at ~8.3kyr BP, as indicated by a marked change in the dinocyst assemblages and in the sediment lithology. Changes in the pollen assemblages indicate a reduction in forest cover after ~5kyr BP, which was likely caused by increased anthropogenic pressure on the regional vegetation.

The Unaz Formation: A Key Unit in the Western Black Sea Region, N Turkey

The Pontide magmatic belt in the Western Pontides, which developed in response to the northward subduction of the northern branches of the Tethys Ocean, consists of two different volcanic successions separated by an Upper Santonian pelagic limestone unit, the Unaz Formation. The first period of volcanism and associated sedimentation started during the Middle Turonian and lasted until the Early Santonian under the control of an extensional tectonic regime, which created horst-graben topography along the southern Black Sea region. The lower volcanic succession, the Dereköy Formation, was deposited mainly within these grabens. This extensional period probably represents the rifting of magmatic arc, giving rise to the opening of the Western Black Sea back-intra-arc basin. The Unaz Formation commonly covers horsts and grabens developed before its deposition. This formation implies sudden subsidence of the region and termination of the volcanism during the Late Santonian. This period was interpreted as the time of the beginning of the oceanic spreading in the Western Black Sea Basin. The second period of magmatism developed on the Unaz Formation was more voluminous and was active during the Campanian. Stratigraphy, contact relationships and regional correlations indicate that the deposition of the Unaz Formation and similar deep marine red pelagic sediments in the Black Sea and Eastern Mediterranean region were probably controlled by local and regional tectonic events and sea level and/or climate changes.

476 Vegetation response to abrupt climate changes in the southern Black Sea region during MIS3, glacial Terminations 1 and 2

476 Vegetation response to abrupt climate changes in the southern Black Sea region during MIS3, glacial Terminations 1 and 2

Phylogeography of the Middle Eastern tree frogs ( Hyla, Hylidae, Amphibia) as inferred from nuclear and mitochondrial DNA variation, with a description of a new species

Evolutionary relationships of the tree frogs from the Middle East and the demographic histories of their populations were studied using a combination of mitochondrial and nuclear genes. Hyla savignyi and neighboring populations of H. orientalis (former eastern populations of H. arborea) were the main focus taxa. Within H. savignyi, a deep phylogenetic divergence dated about 8.4 Ma was discovered. Southern populations from Yemen, Jordan, southern Syria and extreme north-eastern Israel are hereby described as a new species, H. felixarabica sp. nov. Our study points to a biogeographic connection of the south-western Arabian Peninsula and southern Levant and to the importance of the Dead Sea Rift as a historical barrier geographically separating the new species from H. savignyi. Major genetic breaks revealed within species ( H. felixarabica: Yemen vs. Jordan–Syria; H. savignyi sensu stricto: Levant vs. Turkey–Iran) are probably connected to climate changes during the Plio–Pleistocene boundary, while the finer phylogeographic structuring probably resulted from the Quaternary climate oscillations. The Cypriote population of H. savignyi originated from southern Anatolia relatively recently. Hyla orientalis from the southern Black Sea region seems to be genetically quite uniform, although two phylogeographic units with western Turkish and Caucasus–Caspian affinities might be detected. Hyla savignyi and H. orientalis carry signals of population expansions dated to the middle to late Pleistocene, while populations of H. felixarabica seem to have rather been constant in size, which might indicate more stable climatic conditions in the southern regions during the Quaternary.

Marine litter transportation and composition in the coastal southern Black Sea region.

Marine litter problem has gained great attetion in regional seas and lead to degredation and threaten aquatic life in marine environment. Coastal marine litter in the Black Sea is mainly caused by transportation and deposition of antropogenic waste resulting from river outflows. Measures and regulations remain inadequate to protect the coastal regions against pollution in the region. Geomorphology of the region creates many watersheds supplied by extensive stream networks. To estimate litter load on the Black Sea coastal areas 15 streams were surveyed. Study area is densely populated coastal region with scattered settlemets toward steep higher areas. Dry solid waste load is triggered by settlement plan and leads to accumulation of marine litter in coastal areas. Regional precipitation characteristic of the region determines flood timing and frequency with very high rainfall records. Composition and distrubution of sampled marine litter is carried out by identifying litter type propotionality to total load. Plastic has the highest ratio of 56% among all litter type. Yearly total litter load for Degirmendere stream is estimated 102.25 m3/year for 100 ha. Multispectral satellite images are used to asses transportation of floating or drifting litter from coastal areas to inner basin. Man made alterations of coastal areas are also evaluated in terms of aquatic living resources and pollution. Main problems are stressed and possible solutions and implications are given to reduce pollution problem in coastal areas. Key words: Marine litter, Black Sea, satellite remote sensing.

Bacteria in Rainbow Trout (Oncorhynchus mykiss) in the Southern Black Sea Region of Turkey - A Survey

Thirty-two freshwater rainbow trout (Oncorhynchus mykiss) farms, two rain- bow trout marine cages, and one research station in the Black Sea region of Turkey were surveyed for bacterial pathogens and diseases in 2006- 2008. Forty bacterial isolates were phenotypically identified in 558 fish. Yersiniosis, furunculosis, vibriosis, motile Aeromonas septicemia, bacterial cold water disease, and Pseudomonas infection were recorded. Infections caused by Yersinia ruckeri, A. hydrophila, and A. salmonicida occurred most frequently, but one or two outbreaks of P. putida, Flavobacterium psy- chrophilum, and P. luteola infection were also recorded. Most of the bacte- ria were isolated in spring and summer rather than fall and winter. Susceptibility to antibiotics was fairly consistent regardless of geographic area or year of isolation. Fifty percent or more of the bacteria were resistant to ampicillin, cephalothin, erythromycin, neomycin, sulfamethoxazole, tetra- cycline, and O/129. The most effective antibiotics were oxolinic acid and flo- refenicol.

The grain trade in the Southern black Sea region: The thirteenth to the fifteenth century

(1993). The grain trade in the Southern black Sea region: The thirteenth to the fifteenth century. Mediterranean Historical Review: Vol. 8, No. 1, pp. 55-73.