It is known that degassing processes are currently observed in the underwater part of the beach z... more It is known that degassing processes are currently observed in the underwater part of the beach zone of Laspi Bay (the southern coast of Crimea). The site of gas emissions (methane) is confined to the coastal part of the bay and located at a distance of 15.0 – 40.0 m from the coastline. Data on the taxonomic richness and quantitative development of meiobenthos in Laspi Bay (2017) are presented for the first time in this study. The meiobenthic assemblages of the studied area were very diverse including representatives of 24 high taxa from Protozoa and Metazoa (phylum, class, order). The most numerous group at almost all stations was the free-living nematodes. The taxonomic richness by station did not reveal any noticeable variability, including 12 to 18 faunal groups, while an unevenness of spatial distribution in the density of meiobenthic settlements was clearly expressed. Minimum values of 63.2×103–72.9×103 ind./m2 were noted in the seaward zone, and maximum values of 1368×103–205...
Bu çalışma, Türkiye'nin Kuzeydoğu Ege Denizi kıyılarında dağılım gösteren Turridae (gastropod... more Bu çalışma, Türkiye'nin Kuzeydoğu Ege Denizi kıyılarında dağılım gösteren Turridae (gastropoda, mollusca) türlerinin ele almaktadır. Bu amaçla 2000-2002 yılları arsında saros Körfezi ve İzmir Körfezi arasında kıyı şeridinde, derinlikeri 15-105 m arasında değişen 18 istasyonun çeşitli biyotoplarından, drej ve grap kullanılarak, örneklemler yapılmıştır. Materyalin analizi sonucunda, 6 farklı biyotopta dağılım gösteren 9 genus, 20 tür ve bunlara ait toplam 142 birey tespit edilmiştir. Tespit edilen türlerin belirgin kabuk özellikleri kullanılarak tayin anahtarı oluşturulmuşt ve bu türlerin ekolojik ve coğrafik dağılım özellikleri de incelenerek sonuçlar grafiksel olarak ifade edilmiştir. Söz konusu istasyonların değerlendirimesi sonucu, en baskın ve yaygın türlerin Raphitoma linearis (Montagu, 1803), Mangelia costulata (blainville, 1829) ve Bela brachystoma (Philippi, 1844) olduğu saptanmıştır. İstasyon arasında en fazala tür ve birey sayısının 9 tür ve 52 birey ile 9.nolu istasyon...
Environmental Science and Pollution Research, 2021
A microcosm bioassay was designed to assess the efficacy of wastewater treatment methods used in ... more A microcosm bioassay was designed to assess the efficacy of wastewater treatment methods used in sewage plants. The taxonomic and feeding characteristics of a meiobenthic nematode assemblage from Ghar El Melh lagoon (Tunisia) were used to achieve this goal. Nematode assemblages were exposed for 30 days to untreated wastewater (UW) obtained from the sewage treatment plant of Sidi Ahmed (Tunisia) and three mixtures with treated wastewater (TW33 = 33%, TW66 = 66%, and TW100 = 100%). Concerning the nematode abundance, the exposure to either treated wastewater (TW33-100) or untreated wastewater (UW) had no significant effect. In contrast, Shannon-Wiener index and Pielou’s Evenness were clearly reduced by contamination with both types of wastewater, with a more pronounced negative impact prior to treatment in the sewage plant. The multivariate analyzes revealed a change in the taxonomic composition of the nematofauna in response to the contamination by untreated or treated wastewater. The relative abundances of species in wastewater replicates compared to controls reflected this taxonomic restructuring. Finally, Ascolaimus elongatus , Terschellingia communis, and Kraspedonema octogoniata were less represented in all experimentally treated units and could be considered as ‘sensitive taxa to wastewater’. While, Paracomesoma dubium , appears to be a ‘tolerant and/or opportunistic’ species, showing increased relative abundances under all wastewater treatments.
An experimental study was carried out to determine the effects of the enrichment of sediments by ... more An experimental study was carried out to determine the effects of the enrichment of sediments by endocrine perturbators on free-living nematodes from the Ghar El Melh lagoon, Tunisia. For 30 days, four concentrations of Estradiol Benzoate (hereafter EB) (0.43, 4.3, 8.6 and 12.9 ng l-1). The average nematode abundances showed a significant increase after the introduction of EB in their close environment. In contrast, the taxonomic examination has shown a decrease in species diversity of nematodes. The ordination of treatments according to the nMDS showed a clear structural separation of the enriched replicates with EB from controls based on species lists, in particular for concentrations EB3 and EB4. Indeed, under such conditions, the nematofauna exhibited a more remarkable presence of a new record for Science Theristus n. sp. and a decrease in relative abundances of Paracomesoma dubium. On feeding level, a predominance of non-selective deposit-feeders and a decline in proportions of epistrate feeders and carnivorous omnivores was observed with increasing concentrations of EB. Furthermore, in treated replicates with EB, females discernibly showed an increase compared to controls. Overall, EB affect significantly features of meiobenthic nematodes starting from the concentration of 4.3 ng l-1.
Abstract Investigations were conducted at nine stations along the oxic/anoxic interface in the Is... more Abstract Investigations were conducted at nine stations along the oxic/anoxic interface in the Istanbul Strait’s (Bosphorus) outlet area of the Black Sea (ISBS). Present work stands as the first study on the distribution patterns of nematodes along water depths between 75 m and 300 m at the ISBS and gives information on the variability of the trophic relationships of nematodes with oxygen depletion and the presence of toxic hydrogen sulfide in the environment. Nematodes were represented by 137 species from 63 genera and 30 families at the studied depths. 34 species were reported for the first time from Turkey. The presented results showed that most of the nematode species in this region were identified only to the genus and even only to the family or order level. This suggested that the fauna of free-living nematodes of the Black Sea as a whole is much more diverse than is currently known, and requires further taxonomic studies.
Meiobenthic samplings conducted in the framework of a meiobenthos project in the subtidal coastal... more Meiobenthic samplings conducted in the framework of a meiobenthos project in the subtidal coastal waters of Sinop Bay, Southern Black Sea revealed the first report of the kinorhynch Echinoderes dujardinii for the marine fauna of Turkey.
It is known that degassing processes are currently observed in the underwater part of the beach z... more It is known that degassing processes are currently observed in the underwater part of the beach zone of Laspi Bay (the southern coast of Crimea). The site of gas emissions (methane) is confined to the coastal part of the bay and located at a distance of 15.0 – 40.0 m from the coastline. Data on the taxonomic richness and quantitative development of meiobenthos in Laspi Bay (2017) are presented for the first time in this study. The meiobenthic assemblages of the studied area were very diverse including representatives of 24 high taxa from Protozoa and Metazoa (phylum, class, order). The most numerous group at almost all stations was the free-living nematodes. The taxonomic richness by station did not reveal any noticeable variability, including 12 to 18 faunal groups, while an unevenness of spatial distribution in the density of meiobenthic settlements was clearly expressed. Minimum values of 63.2×103–72.9×103 ind./m2 were noted in the seaward zone, and maximum values of 1368×103–205...
Bu çalışma, Türkiye'nin Kuzeydoğu Ege Denizi kıyılarında dağılım gösteren Turridae (gastropod... more Bu çalışma, Türkiye'nin Kuzeydoğu Ege Denizi kıyılarında dağılım gösteren Turridae (gastropoda, mollusca) türlerinin ele almaktadır. Bu amaçla 2000-2002 yılları arsında saros Körfezi ve İzmir Körfezi arasında kıyı şeridinde, derinlikeri 15-105 m arasında değişen 18 istasyonun çeşitli biyotoplarından, drej ve grap kullanılarak, örneklemler yapılmıştır. Materyalin analizi sonucunda, 6 farklı biyotopta dağılım gösteren 9 genus, 20 tür ve bunlara ait toplam 142 birey tespit edilmiştir. Tespit edilen türlerin belirgin kabuk özellikleri kullanılarak tayin anahtarı oluşturulmuşt ve bu türlerin ekolojik ve coğrafik dağılım özellikleri de incelenerek sonuçlar grafiksel olarak ifade edilmiştir. Söz konusu istasyonların değerlendirimesi sonucu, en baskın ve yaygın türlerin Raphitoma linearis (Montagu, 1803), Mangelia costulata (blainville, 1829) ve Bela brachystoma (Philippi, 1844) olduğu saptanmıştır. İstasyon arasında en fazala tür ve birey sayısının 9 tür ve 52 birey ile 9.nolu istasyon...
Environmental Science and Pollution Research, 2021
A microcosm bioassay was designed to assess the efficacy of wastewater treatment methods used in ... more A microcosm bioassay was designed to assess the efficacy of wastewater treatment methods used in sewage plants. The taxonomic and feeding characteristics of a meiobenthic nematode assemblage from Ghar El Melh lagoon (Tunisia) were used to achieve this goal. Nematode assemblages were exposed for 30 days to untreated wastewater (UW) obtained from the sewage treatment plant of Sidi Ahmed (Tunisia) and three mixtures with treated wastewater (TW33 = 33%, TW66 = 66%, and TW100 = 100%). Concerning the nematode abundance, the exposure to either treated wastewater (TW33-100) or untreated wastewater (UW) had no significant effect. In contrast, Shannon-Wiener index and Pielou’s Evenness were clearly reduced by contamination with both types of wastewater, with a more pronounced negative impact prior to treatment in the sewage plant. The multivariate analyzes revealed a change in the taxonomic composition of the nematofauna in response to the contamination by untreated or treated wastewater. The relative abundances of species in wastewater replicates compared to controls reflected this taxonomic restructuring. Finally, Ascolaimus elongatus , Terschellingia communis, and Kraspedonema octogoniata were less represented in all experimentally treated units and could be considered as ‘sensitive taxa to wastewater’. While, Paracomesoma dubium , appears to be a ‘tolerant and/or opportunistic’ species, showing increased relative abundances under all wastewater treatments.
An experimental study was carried out to determine the effects of the enrichment of sediments by ... more An experimental study was carried out to determine the effects of the enrichment of sediments by endocrine perturbators on free-living nematodes from the Ghar El Melh lagoon, Tunisia. For 30 days, four concentrations of Estradiol Benzoate (hereafter EB) (0.43, 4.3, 8.6 and 12.9 ng l-1). The average nematode abundances showed a significant increase after the introduction of EB in their close environment. In contrast, the taxonomic examination has shown a decrease in species diversity of nematodes. The ordination of treatments according to the nMDS showed a clear structural separation of the enriched replicates with EB from controls based on species lists, in particular for concentrations EB3 and EB4. Indeed, under such conditions, the nematofauna exhibited a more remarkable presence of a new record for Science Theristus n. sp. and a decrease in relative abundances of Paracomesoma dubium. On feeding level, a predominance of non-selective deposit-feeders and a decline in proportions of epistrate feeders and carnivorous omnivores was observed with increasing concentrations of EB. Furthermore, in treated replicates with EB, females discernibly showed an increase compared to controls. Overall, EB affect significantly features of meiobenthic nematodes starting from the concentration of 4.3 ng l-1.
Abstract Investigations were conducted at nine stations along the oxic/anoxic interface in the Is... more Abstract Investigations were conducted at nine stations along the oxic/anoxic interface in the Istanbul Strait’s (Bosphorus) outlet area of the Black Sea (ISBS). Present work stands as the first study on the distribution patterns of nematodes along water depths between 75 m and 300 m at the ISBS and gives information on the variability of the trophic relationships of nematodes with oxygen depletion and the presence of toxic hydrogen sulfide in the environment. Nematodes were represented by 137 species from 63 genera and 30 families at the studied depths. 34 species were reported for the first time from Turkey. The presented results showed that most of the nematode species in this region were identified only to the genus and even only to the family or order level. This suggested that the fauna of free-living nematodes of the Black Sea as a whole is much more diverse than is currently known, and requires further taxonomic studies.
Meiobenthic samplings conducted in the framework of a meiobenthos project in the subtidal coastal... more Meiobenthic samplings conducted in the framework of a meiobenthos project in the subtidal coastal waters of Sinop Bay, Southern Black Sea revealed the first report of the kinorhynch Echinoderes dujardinii for the marine fauna of Turkey.
Deep-water meiobenthos of Turkish shelf has been evaluated at the Black Sea exit of İstanbul Stra... more Deep-water meiobenthos of Turkish shelf has been evaluated at the Black Sea exit of İstanbul Strait (Bosphorus) and off Sinop peninsula as a result of three scientific cruises. Taxonomic diversity of meiobenthos communities was studied at the Black Sea exit of Bosphorus on a transect with a depth range of 75-300 m. The bottom sediments were collected at the area during two cruises, on board RV "Arar'' (of Turkey) and ''Maria S. Merian" (of Germany) in November 2009 and April 2010, respectively. Data on meiobenthos inhabiting both normoxic and extreme conditions was collected in the studied area and meiobenthos composition included 26 high level taxa. In addition, 2-3 morphotypes of benthic fauna were recorded as incertae sedis, which require further study. The number of higher taxa decreased from 22 to 14-8 when switching from oxygenic conditions (50-125 m) to the anoxic hydrogen sulphide environment (226-300 m). The constant components of meiobenthos inclu...
Specimens of the gastrotrich genus Musellifer are recorded for the first time from the Black Sea.... more Specimens of the gastrotrich genus Musellifer are recorded for the first time from the Black Sea. These specimens, identified as M. profundus Vivier, 1974, were found in sediment samples collected at various depths (22−135 m) and from waters characterized by low salinity (17.3−18.62‰) and varying levels of oxygen (2.43−299.59 μM). Three specimens were found from the Istanbul Strait (Bosphorus) outlet area of the Black Sea (Turkey) and 2 were found along the southern and southeastern shelf of the Crimean Peninsula (Russia), from the Yalta Gulf and the Feodosiya Gulf.
ABSTRACT In this paper, Megastygarctides sezginii sp. nov., a new marine species from the Black S... more ABSTRACT In this paper, Megastygarctides sezginii sp. nov., a new marine species from the Black Sea (Turkey), is described. Morphological and morphometric studies have revealed that M. sezginii sp. nov. is most similar to M. setoloso Morgan & O’Reilly, 1988, but differs from it through the presence of two types of fibrils, a lack of cuticle granulation, the presence of three lateral projections with fibrils, leg fibrils arranged in transverse stripes and the presence of clumps of fibrils near the clavae. In the studied environment, the new species is frequently found in summer and almost absent in winter. Additionally, a taxonomic key for all Megastygarctides species is presented. http://zoobank.org/urn:lsid:zoobank.org:pub:53AA1D57-8700-4A18-9099-1CDDBAEB4D3A
Biodiversity in coastal ecosystems of the Mediterranean Sea have a long history of intense studie... more Biodiversity in coastal ecosystems of the Mediterranean Sea have a long history of intense studies but investigations in deep-sea habitats are scarce. In collaboration with the (E/V) Nautilus, we examined the Anaximander Seamounts, located in the south of Turkey, at the junction of the Hellenic and Cyprus arcs. Five mud volcanoes (Amsterdam, Kula, Thessaloniki, Kazan, Athina; depths 1250−2300 m) and a non-seep site (Anaximenes Ridge, 818-m depth) were sampled in July/August 2012 and quantitative, soft-sediment cores (6-cm diameter, 10-cm deep) were collected for community analyses and DNA barcoding of organisms. Actively seeping fluid (14°C) containing methane was present at several volcanoes. The seabed was heterogeneous, consisting of soft-sediments interspersed with carbonate crusts harboring mussels and tubeworms. Varying colors of patchy, superficial microbial mats were the most common methane seep habitat. We characterized the distribution and community structure of macro- and...
Deep-water meiobenthos of Turkish shelf has been studied at the Black Sea exit of Bosphorus and o... more Deep-water meiobenthos of Turkish shelf has been studied at the Black Sea exit of Bosphorus and off Sinop peninsula as a result of three scientific cruises.
Free-living marine nematodes were investigated for the first time in the scope of a meiobenthos p... more Free-living marine nematodes were investigated for the first time in the scope of a meiobenthos project. This study is part of a comprehensive research on meiobenthos ecology of Sinop Bay (Southern Black Sea, Turkey) reporting new nematode taxa for the marine fauna of Turkey. With the present study, three chromadorids are reported for the first time from Turkey: Hypodontolaimus sp., Prochromadorella sp. and Spilophorella campbelli Allgén, 1928. The first two genera are also first records for the Turkish nematode fauna. The taxonomical and ecological features of the three species are investigated. DIC (Differential interference contrast) photographs and morphometric measurements are provided and the spatio-temporal distributions of the species are presented.
This study reveals the dynamics and morphological characteristics of the genus Neochromadora Mico... more This study reveals the dynamics and morphological characteristics of the genus Neochromadora Micoletzky, 1924 recorded at Sinop coasts. Two species of the genus, Neochromadora poecilosomoides (Filipjev, 1918) and N. sabulicola (Filipjev, 1918) were registered in the study area throughout the year.
A new record of water bears from Turkey, Megastygarctides setoloso Morgan & O’Reilly, 1988 (Tardi... more A new record of water bears from Turkey, Megastygarctides setoloso Morgan & O’Reilly, 1988 (Tardigrada: Arthrotardigrada)
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