Papers by Neslihan (BALKIS) OZDELICE
Estuarine, Coastal and Shelf Science, 2019
The marine cyanobacterium Synechococcus plays an important role in microbial food webs and is a s... more The marine cyanobacterium Synechococcus plays an important role in microbial food webs and is a significant contributor to primary production in the world's oceans. The abundance distribution of picoplanktonic Synechococcus was investigated in the Gulfs of Bandırma and Erdek (in the Sea of Marmara), in which water samples were taken seasonally between August 2007 and August 2008 during an intense period of mucilage formation. The mucilage phenomenon occurred in the Sea of Marmara between October 2007 and February 2008. In both sites, Synechococcus abundance was highest in November 2007, at 32.68 � 10 4 cells ml 1 in the Gulf of Bandırma and 34.83 � 10 4 cells ml 1 in the Gulf of Erdek, with the high values in November 2007 coinciding with mucilage formation. In contrast, the lowest Synechococcus abundance was 0.85 � 10 4 cells ml 1 in February 2008 in the Gulf of Bandırma and 3.27 � 10 4 cells ml 1 in May 2007 in the Gulf of Erdek. The two-layered structure of the Sea of Marmara affected the vertical distribution of Synechococcus, in which the maximum abundance of Synechococcus occurred in the upper layers and the minimum abundance values at the deeper layers of both gulfs. This layered structure also strongly affected the relationship between Synechococcus and environmental parameters. In this sense, Synechococcus abundance was negatively correlated with salinity and nitrate but was positively correlated with chlorophyll-a in the Gulfs of Bandırma and Erdek but was not correlated with temperature or phosphate in either gulf. Despite the fact that Synechococcus is temperature dependent, the abundance distribution was influenced more by other environmental factors than by temperature.
FIGURE 2–7. Light micrographs of Cymbella balkii sp. nov. Scale bar = 10 µm.
Journal of the Marine Biological Association of the United Kingdom
The aim of this study is to determine the phytoplankton species found on the shores of Burgaz Isl... more The aim of this study is to determine the phytoplankton species found on the shores of Burgaz Island and the basic ecological variables that affect their seasonal distribution between May 2013 and February 2014. Water samples were collected from four stations at six different depths and plankton samples were gathered horizontally and vertically. The analysis of phytoplankton community composition revealed 101 phytoplankton taxa belonging to five classes. As a result of the study, two taxa belonging to the Dinophyceae (Corythodinium frenguellii and Gonyaulax scrippsae) were new records for Turkish coastal waters. Additionally, a taxon belonging to Dinophyceae (Pronoctiluca pelagica) and a taxon belonging to Bacillariophyceae (Nitzschia reversa) were new records for the Sea of Marmara. Prorocentrum micans, was the dominant species throughout all sampling periods. During the study, the highest phytoplankton abundance was observed at 0.5 m depth in May 2013 (138,500 cells l−1) and Febru...
European Journal of Biology, 2021
Objective: In this study carried out in Büyükçekmece Reservoir, the composition, distribution, se... more Objective: In this study carried out in Büyükçekmece Reservoir, the composition, distribution, seasonal changes of epiphytic diatoms that live on the surfaces of plants, and the effects of environmental parameters on these organisms were investigated, and it was aimed to reveal the water quality of the reservoir. Materials and Methods: In order to determine the seasonal changes of epiphytic diatom species in Büyükçekmece Reservoir, water and material samples were collected from five stations in 2019. In the study, water temperature, salinity, conductivity, dissolved oxygen, and pH values, which are among the basic ecological variables, were measured. Epiphytic diatom samples were obtained from Phragmites sp. species. Also, Spearman's rank correlation, Shannon-Weaver diversity index, Cluster (Bray-Curtis and Euclidean Distance), and ordination analysis (DCA and CCA) were applied in the study. Results: 66 epiphytic diatom species were identified in this study, and 36 of these species are new records for the reservoir. Most epiphytic diatom species were obtained in August, and the lowest number was obtained in November. According to the pH values, it was determined that the reservoir is alkaline. In addition, it was determined that the main factors affecting the distribution of epiphytic diatom species in the reservoir are temperature and conductivity, and it was revealed that ecological variables affect species distribution. Conclusion: According to conductivity and DO values, it was determined that the reservoir was of very good and of good quality, and in terms of DO values, the reservoir was mainly oligotrophic. However, station 5 was mesotrophic during the August sampling period, station 4 was mesotrophic, and station 5 was eutrophic in November. Also, Büyükçekmece Reservoir was found in poor and moderate status according to H' classification.
The Bulletin of Legal Medicine, 2020
Amaç: Tetikleyici neden farklı olsa da ölümcül dalış kazalarının büyük bir bölümü boğulma ile son... more Amaç: Tetikleyici neden farklı olsa da ölümcül dalış kazalarının büyük bir bölümü boğulma ile sonuçlanmaktadır. Boğulmanın gerçekleştiği derinliği bilmek, kaza nedenlerinin aydınlatılmasına önemli katkıda bulunabilir. Bu deneysel çalışmada, ölümcül dalış kazalarında, boğulma derinliğinin tespitinde planktonik organizmaların kullanılıp kullanılamayacağı amaçlanmıştır. Gereç ve Yöntem: Bunun için Marmara Denizi’nde yüzeyden ve 30 metre derinlikten alınan su örneklerindeki planktonik organizmalar incelenmiştir. Ayrıca Wistar Albino türü 8 bireyden oluşan iki gruptan ilkinde bulunan sıçanların yüzeyden alınan su örneği içinde ve 1 ATA basınç altında, diğer grupta bulunan sıçanların ise 30 metre derinlikten alınmış su örneği içinde ve bir basınç odası içinde 4 ATA basınç altında boğulmaları sağlanmış ve boğulan sıçanların akciğerlerinde planktonik organizmalar araştırılmıştır. Bulgular: Yapılan incelemelerde, yüzeyden alınan örnekte 22 fitoplanktonik ve 5 zooplanktonik takson, 30 metre d...
Phytotaxa, 2021
The descriptions of the new species Cymbella balkii sp. nov. and C. yerlii sp. nov. were given in... more The descriptions of the new species Cymbella balkii sp. nov. and C. yerlii sp. nov. were given in this study. The species were found in a karstic limnocrene spring which is one of the most important sources of Sakarya River. Cymbella balkii sp. nov. is very similar to C. pervarians, C. simonsenii, C. percymbiformis, C. perparva, C. alpestris and C. vulgata. Among them, C. pervarians is the most similar taxon however, the former has higher stigmata number and larger valve than the latter. Cymbella yerlii sp. nov. is very similar to C. parva, C. perparva and C. parviformis are similar taxa. Among them, C. parva is the most similar taxon in all related ones with similar outline. However, length/width ratio is higher in C. yerlii than the other taxa.
The Southwestern Black Sea region has an intense city life where swimming, fishery and shipping a... more The Southwestern Black Sea region has an intense city life where swimming, fishery and shipping are widespread practices. It is crucial to determine and trace the levels of microbiological contamination of such places in terms of public health. Within the scope of this study, we collected samples from the surface water of the sea in 10 different areas (St1-10) between İğneada-Kilyos seasonally and analyzed them in terms of fecal coliform (FC), total coliform (TC), fecal streptococci (FS), total mesophilic heterotrophic bacteria (TM), Pseudomonas spp. (P) and Aeromonas spp. (A) through bacterial isolation. The antibiotic and heavy metal resistance profiles of the isolated bacteria were also investigated. According to results, the most polluted stations are St5, St7 and St10. When the results were evaluated on a seasonal basis, the highest TC, TM, P and A counts were observed in the summer while the maximum FC and FS counts were observed in the winter and autumn, respectively. When FC/FC ratios were examined, it was detected that the contamination in St1-3 was of only animal origin, but the contamination in the other stations was of both animal and human origin. In this study, we isolated 153 bacteria of 43 different species, notably E. coli (25%), Fecal streptococci (15%), Pseudomonas fluorescens (9%) and Aeromonas hydrophila (8%). When the antibiotic and heavy metal resistance profiles of the isolated bacteria were examined, it was observed that the stations had been exposed to a serious contamination stemming from human activities in relation to fecal and industrial wastes.
Acta Aquatica Turcica, 2019
Bu calisma, Erdek ve Bandirma Korfezi’nde siliyat turlerini ve bu turlerin dagilimini etkileyen c... more Bu calisma, Erdek ve Bandirma Korfezi’nde siliyat turlerini ve bu turlerin dagilimini etkileyen cevresel degiskenleri belirlemek amaciyla, 2006 ve 2008 yillari arasinda her iki korfezde ucer istasyonda mevsimsel olarak gerceklestirilmistir. Calisma sonucunda ucu cins duzeyinde toplam 14 siliyat taxasi belirlenmistir. Bulunan turlerden Epiplocyloides sp., Proplectella ovata , Laboea strobila ve Tiarina fusus Marmara Denizi icin yeni kayit turlerdir. En fazla tur sayisi 11 tur ile Choreotrichida ordosuna aittir. Choreotrichida ordosunun yaz mevsiminde en fazla cesitliligi sahip oldugu belirlenmistir. Bu calismada kullanilan ekolojik veriler, ayni bolgede es zamanli yapilmis onceki calismadan alinmistir. Spearman’in sira korelasyonuna gore ekolojik degiskenlerden tuzluluk, DO, Chl-a ve NO 3 + NO 2 -N’in ciliatlarin dagilimini etkiledigi, derinlik artisina bagli olarak tuzlulugun arttigi ve tur bollugunun azaldigi belirlenmistir. Istasyonlar arasinda en yuksek benzerlik, Bandirma Korfez...
International Journal of Environment and Geoinformatics, 2021
In the intense mucilage formation observed in the Sea of Marmara in 2021, Phaeocystis pouchetii (... more In the intense mucilage formation observed in the Sea of Marmara in 2021, Phaeocystis pouchetii (Prymnesiophyceae) together with Skeletonema costatum, Cylindrotheca closterium, Thalassiosira rotula (Bacillariophyceae), and Gonyaulax fragilis (Dinophyceae) were detected in the foamy mucilage in the surface layer, and Chrysoreinhardia giraudii and Nematochrysopsis marina (Chrysophyceae), which are known to produce filamentous mucilage in benthic habitat. In addition, with the contribution of these groups, a higher cell abundance (2.1×10 7 cells/L) and chlorophyll-a value (15.9 µg/L) was reached than the mucilage event experienced in previous years. In the microscopic observations, typical dominant genera of the Sea of Marmara such as Protoperidinium and Tripos were observed very little in terms of species composition, and the fact that three previously unobserved species became dominant and the Cyanophyceae group was represented by different species indicated that phytoplankton composition changed in the mucilage formation in this period. The changing species composition with these three species that are known to make mucilage and which are new records for the Sea of Marmara point to the transportation by ship ballast waters or the inflow of brackish water with heavy rains. It is recommended to take the necessary measures to control domestic and industrial wastes and terrestrial inputs, which cause these species to reach numerical abundance and form mucilage, to carry out fisheries in a controlled manner, and to prevent the discharge of ship ballast waters and bilge waters.
Acta Aquatica Turcica, 2019
This study was carried out seasonally in order to determine the environmental variables affecting... more This study was carried out seasonally in order to determine the environmental variables affecting the ciliate species and their distribution in Gulfs of Erdek and Bandırma by using three stations in each gulf between 2006 and 2008. A total of 14 ciliates taxa were identified, three of them were the genus level. Epiplocyloides sp., Proplectella ovata, Laboea strobila and Tiarina fusus species identified are the new records for the Sea of Marmara. The maximum number of species belonged to the Choreotrichida ordo with 11 taxa. The Choreotrichida ordo showed the highest diversity in summer season. The ecological data used in this study were obtained from the previous study concurrently conducted in the same region. According to the Spearman's rank-correlation, it was determined that the salinity, dissolved oxygen (DO), chlorophyll-a (Chl-a) and NO3+NO2-N levels affected the distribution of the ciliates and the salinity was increased and species abundance was decreased based on the rise in depth. The highest similarity between the stations was observed in stations 2 and 3 in the Gulf of Bandırma at a depth of 0.5 m (96.5%) and all the depths of the stations were found to be 23.6% similar.
Marine Pollution Bulletin, 2017
Phytoplankton assemblages related to environmental factors and ecological status of the Gemlik Gu... more Phytoplankton assemblages related to environmental factors and ecological status of the Gemlik Gulf were investigated between June 2010 and May 2011. A total 155 phytoplankton species were detected and 6 taxa (Amphisolenia laticincta, Archaeperidinium minutum, Cochlodinium sp., Gynogonadinium aequatoriale, Heterocapsa rotundata and Metaphalacroma sp.) were new records for the Turkish Seas. The lowest and highest total phytoplankton abundance among the sampling units (depths) was recorded in April 2011 (7.4 × 10 3 cells L −1) and July 2010 (251.8 × 10 3 cells L −1). Local small patches of visible red tide events were detected especially in the gulf, although a phytoplankton bloom was not observed. The water column was well stratified in the early autumn and well mixed in the early spring according to stratification index values. Surface nutrient concentrations increased especially at stations located inside of the gulf. The limiting effect of silicate was observed in early, midsummer and early winter periods while the nitrogen was the limiting nutrient in the gulf during the whole sampling period. In the Gulf, low water quality-high mesotrophic and bad water quality-eutrophic status, high quality and low trophic level were generally detected according to Chl a, dissolved oxygen and trophic index. However, indices developed to determine the trophic level and water quality of the Mediterranean Sea can give unexpected results about the current environmental quality status when it is applied to the Marmara Sea which has limited photic zone by the halocline-pycnocline and thermocline.
Phycologia, 2016
Abstract: Thirty-four dinoflagellate cyst taxa were found in surface sediment (0–2 cm) at five st... more Abstract: Thirty-four dinoflagellate cyst taxa were found in surface sediment (0–2 cm) at five stations (60–100-m water depth) in the Gulf of Gemlik, Marmara Sea, during four seasons from August 2011 to May 2012. Lingulodinium machaerophorum, Operculodinium centrocarpum and Selenopemphix quanta dominated cyst assemblages in the polluted gulf, where nutrient-rich surface water was stratified during most seasons and bottom water was hypoxic. Twelve cyst taxa were incubated and produced motile cells that reproduced and survived 14–15 days. Highest cyst species number (33) occurred in summer; maximum number of cysts (living and empty) per cm3 wet sediment was in spring, with the annual range from 1520 (fall) to 108,000 (spring). Nine taxa (Brigantedinium simplex, L. machaerophorum, O. centrocarpum, S. quanta, Spiniferites mirabilis, Spiniferites ramosus, cysts of Alexandrium sp., Scrippsiella trifida and S. trochoidea) were found in all seasons at all stations. The harmful dinoflagellates L. machaerophorum and cysts of S. trochoidea and Alexandrium sp. were the most abundant species. The cyst of the toxic species, Cochlodinium sp., is reported for the first time from Turkey. Other HAB species included A. tamarense, Protoceratium reticulatum, Heterocapsa triquetra and Gymnodinium catenatum/nolleri. Relative abundance of potentially toxic dinoflagellates (74%–92% of total cysts cm−3) was always higher than nontoxic species, and percentage abundance of cysts cm−3 produced by autotrophs (19/34 total species) almost always exceeded those of heterotrophs. Although distributions of the resting cyst taxa were significantly influenced by surface temperature, dissolved oxygen and total water depth, surface salinity was the strongest predictor for cyst occurrences.
Abstract This study was carried out in order to determine hydroid polyp species present in the Bo... more Abstract This study was carried out in order to determine hydroid polyp species present in the Bosphorus and some ecological properties of. these species. Samples were collected at 19 stations from depths ranging 0.5- 60 m by using spatula, beam-trawl and dredge. As a result of this study, 14 species belonging to 10 genera and 6 families were determined and 4 species among them (Tubularia cf. indivisa Linnaeus, 1758, Halecium beanii (Johnston, 1838), Halecium labrosum Alder, 1859, Laomedea exigua M. Sars, 1857) were seen to be new records for the fauna of the Bosphorus, according to present literature.
Abstract This study was carried out to present the species list of the Crustacea fauna of the Bos... more Abstract This study was carried out to present the species list of the Crustacea fauna of the Bosphorus in the light of the previously conducted research. It was seen that totally 94 crustacean species had been recorded from this region and Amphipoda was the first and Decapoda was the second in respect to the species number, with 37 and 36 species, respectively.
This first comprehensive study was carried out on current ecological quality status of the Kapida... more This first comprehensive study was carried out on current ecological quality status of the Kapidag Peninsula between the years of 2011 and 2012. The samples were collected seasonally from 5 different depths (0.5-30 m) at 3 stations determined from shore to offshore. During the study, temperature, salinity and dissolved oxygen levels of the seawater ranged between 7.5-26.0 °C, 18.06-35.06 ppt and 2.77-10.33 mg L -1 , respectively. Nitrate+nitrite-N (0.01-5.39 μg-at N L -1), ammonium-N (0.01-0.79 μg-at N L -1), phosphate-P (0.01-1.48 μg-at P L -1) and silicate-Si (0.52-21.18 μg-at L -1) concentrations were measured, and also chlorophyll-a (chl-a) values ranged between 0.02-4.21 μg L -1 . The chl-a concentration is an important bioge-ochemical quantity monitored a present pigment in all phytoplankton species and, for this purpose commonly used as an index of biomass. In addition, the spatial and tem-poral patterns of chl-a concentration seawater temperature and nutrients are important ...
Mediterranean Marine Science, 2010
In this paper, we describe the pelagic and benthic ecosystem of the Golden Horn estuary opening ... more In this paper, we describe the pelagic and benthic ecosystem of the Golden Horn estuary opening into the Marmara Sea. To improve the water quality of the estuary, which had long been subject to severe anthropogenic pollution (industrial, chemical, shipping), industrial facilities were moved from the estuary in the 1980s, followed by a rehabilitation plan in the 1990s. Our results, based on chemical parameters and phytoplankton showed some signs of improvement of water conditions in the upper layer. However, macrozoobenthic findings of this study did not reflect such a recovery in bottom life.An approach to the Ecological Quality Status (EQS) assessment was performed by applying the biotic indices BENTIX, AMBI, BOPA, BO2A. Our final assessment was based on 'expert-judgements' and revealed a very disturbed overall ecosystem with 'bad' EQS for the station at the head of the estuary, 'poor' in the rest of the estuary and 'moderate' EQS only in the midd...
Journal of the Marine Biological Association of the United Kingdom, 2010
This study was implemented to determine the environmental factors and causative organisms of the ... more This study was implemented to determine the environmental factors and causative organisms of the recent mucilage formation in the Marmara Sea. Samples were taken during the study from 7 different depths (0.5–30 m) of one sampling point of the Büyükada Island shore between January and June 2008. As a result, 62 phytoplankton species belonging to 5 different groups were identified. Dinoflagellates were dominant in terms of species number, and diatoms in terms of cell number. In January and February, mucilage formation was very dense, where 5 phytoplankton species (Clindrotheca closterium, Pseudo-nitzschiasp.,Skeletonema costatum, Thalassiosira rotula(Bacillariophyceae) andGonyaulax fragilis(Dinophyceae)) were reported as dominant organisms. Among them,Gonyaulax fragilishas never been reported in the Marmara Sea previously, thus that organism appeared firstly with the formation of dense mucilage and then when the mucilage decayed in May and June 2008,G. fragilisdisappeared. Autofluores...
… OF SELECTED PAPERS, 2004
... UYSAL, A., A. YÜKSEK & E. OKUŞ. ... Received: 8 January 2002 Accepted: 9 December 200... more ... UYSAL, A., A. YÜKSEK & E. OKUŞ. ... Received: 8 January 2002 Accepted: 9 December 2003 Fauna koljkaa (mekuaca) Mramornog mora Serhat ALBAYRAK, Hüsamettin BALKIS i Neslihan BALKIS Sveučilite u Istanbulu, Fakultet Znanosti, Odsjek Biologije, 34118 Vezneciler ...
Uploads
Papers by Neslihan (BALKIS) OZDELICE