Poster Presentation - Oceanography 2018
Jerzy Bolalek
University of Gdansk, Poland
Methane occurrence in sediments of the Gdansk Basin (Southern Baltic Sea)
Jerzy Bolalek(Biography)
Jerzy Bolalek is a Full Professor at the Gdansk University and Head of the Department of Marine Chemistry and Marine Environment Protection at the Faculty of Oceanography and Geography. He specializes in the field of chemical oceanography, hydrochemistry and environmental protection. The most important scientific achievements are: authorship or co-authorship of about 150 works, of which about 60 are original works published in English in international journals. He is also the author and co-author of a number of expert reports on the quality of marine waters as well as two Polish standards. He is a member of the Research Committee of the Polish Academy of Sciences and editorial committees of the Journal of Marine Science and Research since 2016 and Oceanological and Hydrobiological Studies. He also has extensive experience in assessing the quality of education at Polish universities.
Jerzy Bolalek(Abstract)
Introduction: Methane is regarded as an important gas not only from the economic but also environmental point of view. Geochemical results showed that methane in sediments of the Gdansk Basin is predominantly of the microbiological origin and the depth in sediments below which methane production takes place is relatively shallow (in some areas even 10-20 cm bsf). Methodology & Theoretical Orientation: Methane occurrence in marine sediments was determined during five research campaigns in the area of the Gdansk Basin during 2009-2017. Sediment cores were collected at 10 stations using a Rumohr Lot corer and a Niemisto-type corer. At each station, separate cores were taken for: 1) methane analysis 2) water content and loss on ignition 3) pore water extraction for the analyses of SO42-, TDS, NH4+ and DIC (or total alkalinity). Samples were analyzed based on headspace techniques on the gas chromatograph with FID detector. Pore waters were extracted using Rhizon samplers. Findings: It was found that methane is common in shallow sediments of the Gdansk Basin. It is predominantly of the microbiological origin and its production starts already at sediment depths of 10-20 cm bsf. Although methane concentrations in sediments are high, its values in near-bottom waters are relatively low, which point to effective methane oxidation processes that prevent the emission of this gas to surface waters and the atmosphere. Conclusion & Significance: Shallow sediments of coastal sea waters can be considered as methane production hot-spots and should be monitored in terms of methanogenesis zone depth, methane emission from the sea bottom (especially gas ebullition events) and the area of gas abundance in the bottom. Our research indicated the amount of methane in sediments of the Gdansk Basin decreased between 2009 and 2017, the depth of methane production increased, and the constant gas outflow finished.
Mohammad Al Mukaimi
Kuwait University, Kuwait
Assessment of the high-resolution paleoseismicity record from sediment gravity flows in Prince William Sound, Alaska
Mohammad Al Mukaimi(Biography)
Mohammad Al Mukaimi is a Marine Geochemist at the Marine Science Department of Kuwait University. He received his PhD in Oceanography from Texas A&M University 2016. During his PhD he worked on geochemical and sedimentary record of urbanization and industrialization of the Galveston Bay watershed with Dr. Dellapenna. His research focuses on marine sediments geochemistry, seabed dynamics and sedimentary processes and trace metals in aquatic system.
Mohammad Al Mukaimi(Abstract)
Located along the Aleutian Megathrust boundary, South central Alaska is one of the most seismically active areas in the world. Central to this region, Prince William Sound is a glacially carved basin that receives abundant sediment from multiple sources. Primary inputs include the Columbia glacier and the Copper River which have diagnostic signatures of Sr/Pb, Cu/Pb, K/Ca, Rb/Sr and Rb/Ca. As a result of earthquake induced sediment gravity flows originating from different locations and deposit event layers that have distinct provenance signatures. A previous study identified five such event layers preserved in two cores from the southern part of the deep central channel of Prince William Sound that were attributed to large historical earthquakes. To understand better the spatial continuity of these event layers along the entire length of the central channel, seven new gravity cores were collected in a north-south transect. Sedimentation rates were determined by 210Pb, 137Cs and 239,240Pu geochronology and cores were assessed for variations in elemental content, grain size patterns, bulk organic and stable isotopic signatures (C/N, δ13C, δ15N). Based on a spatial analysis of these cores, local earthquakes of Mw<7.0 deposit event layers in the central channel with signatures reflecting the epicenter location and those of Mw>7.0 (including an event layer from the 1964 great Alaskan earthquake) have mixed signatures resulting from the widespread generation of numerous flows throughout Prince William Sound. Complete gravity flow records are captured within deep ponded sediment basins and the area spanning the southern end of the central channel. Considering the thick (>100 m) late Holocene sequence, the approach utilized in this study has the potential to provide a rich record of earthquake recurrence of intervals to 4 ka.
Sanja Puljas
University of Split, Croatia
Infection status of Mytilus galloprovincialis (Bivalvia, Mytilidae) with trematode Parvatrema sp., (Digenea, Gymnophallidae) in Kastela Bay, Adriatic Sea
Sanja Puljas (Biography)
Species Mytilus galloprovincialis Lamarck, 1819 is a dominant mussel on the rocky intertidal of the Adriatic Sea, Croatia. The beds of M. galloprovincialis were in regression during 2014, but the population recovered. In 2018, a new population decline was recorded. Due to those fluctuations, trematode infection was noticed. Based on morphology and observation of the sporocysts, cercariae and metacercariae in mussel's mantle and gonads, the trematode species is identified as Parvatrema sp., and a total of 40 individuals were collected during February and March 2014 and 2018 from the rocks at Kastel Stari. In the laboratory, the mantle and gonads of each measured mussel were macroscopically and microscopically examined and photographed with Axio Camera MRc5. Trematode morphology was observed and measured using the axio vision release 482SP3 program (08-2013). Mussel tissues with different developmental stages of trematode have been fixed in 4% formaldehyde and following routine histological procedures, sections have been stained in Ehrlich's haematoxylin and eosin. Based on histology, an infection prevalence (number of infected mussels/total number of mussels) and weighted infestation (infection intensity/ total number of mussels) were calculated according to year of sampling, sex and length of mussels. Results showed that the prevalence of infection for 2014 was 100% while in 2018 it was 65%. During both years, neither there was significant difference in the prevalence of infection among males and females nor between different shell lengths, presuming high infectious potential. Weighted infestation was not much lower in 2018, indicating that the number of individuals in this population could be reduced again due to new infection. Since the definitive host of gymnophallids are known to be marine and coastal birds and assuming that in Croatia the relationship between birds and trematode infection has not been reported previously and more attention should be paid to this subject.
Sanja Puljas (Abstract)
Sanja Puljas is an Assistant Professor at the University of Split, Croatia, Faculty of Science. Her research is related to bivalve ecology with special attention to reproduction, growth dynamics, sclerochronology and population dynamics of bivalves. She obtained her Master’s degree in Biology from University of Zagreb, Croatia, Faculty of Science and PhD in Applied Marine Sciences from University of Split, Croatia. Her Doctoral research was focused on the ecology of the troglodytic living fossil Congeria kusceri (Bivalvia: Dreissenidae) from the subterranean Dinaric Alpine karst. She has extensive experience in field work of the underground habitat and Adriatic Sea. Her research activities cover the skills of histology and preparation of shell acetate peel replicas including the interpretation of bivalve growth data and anatomy.
Md Rajib Sharker
Chonnam National University, Republic of Korea
Molecular architecture and characterization of an actin gene from the pacific abalone, Haliotis discus hannai
Md Rajib Sharker(Biography)
Md Rajib Sharker has completed his graduation in the Fisheries Biology and Genetics. During his graduation program he has published research article regarding biology of fishes in peer reviewed journal. Now, he is conducting PhD program in the Molecular Physiology lab under the division of fisheries science, Chonnam National University. Currently, he is working on molecular cloning and isolation of growth and reproduction related gene from the pacific abalone, Haliotis discus hannai. He also gained insight of knowledge concerning larval and embryonic development of abalone species which will be assisted on rearing and culture technology of abalone.
Md Rajib Sharker(Abstract)
Statement of the Problem: Actins are highly conserved proteins of ATPase super family that involved in the ATP binding domain of the Hsp70 related proteins, sugar kinases, actin-related proteins and prokaryotic actin homologue. In this study, a 976 bp sequence was cloned from the neural ganglion of pacific abalone, Haliotis discus hannai. The coding sequence of 270 bp translated into a protein of 89 amino acid residue. A BLAST search indicated that this protein represents 68% and 56% identity with rainbow abalone and pacific oyster respectively. Moreover, alignment of two or more sequences revealed that the amino acid sequence of Haliotis has 42-56% similarity with mammalian and other abalone actin sequences. Phylogenetic analysis demonstrates that our predicted clone formed cluster with rainbow abalone due to intense similarity of amino acid signature. Semi quantitative reverse transcription (RT)-PCR, quantitative PCR (q-PCR) confirmed that actin gene is highly expressed in Cerebral Ganglion (CG) which indicates CG might be correlated with abalone cell motility, structure, integrity and intercellular signalings