Journal of Oceanography and Marine Research最新文献

Feasibility Study on Unmanned Aerial Vehicle-Based Undersea Acoustic Sensing 基于无人机的水下声传感可行性研究

Journal of Oceanography and Marine Research Pub Date : 1900-01-01 DOI: 10.35248/2572-3103.19.7.192

P. Chu, Loney R Cason

引用次数: 0

Environmental Research and Geochemical Evaluation of Recent Bottom Sea Sediments North and North –East of Lesvos Island, Greece 希腊莱斯沃斯岛北部和东北部近期海底沉积物的环境研究与地球化学评价

Journal of Oceanography and Marine Research Pub Date : 1900-01-01 DOI: 10.35248/2572-3103.19.7.188

A. Kelepertsis, Andreas Andrinopoulos

{"title":"Environmental Research and Geochemical Evaluation of Recent Bottom Sea Sediments North and North –East of Lesvos Island, Greece","authors":"A. Kelepertsis, Andreas Andrinopoulos","doi":"10.35248/2572-3103.19.7.188","DOIUrl":"https://doi.org/10.35248/2572-3103.19.7.188","url":null,"abstract":"An environmental and geochemical investigation of 33 surficial sediments of the continental shelf north and north east of Lesvos Island Greece was undertaken to study the mineralogy and geochemistry of the sediments and understand the distribution and sources of various major and trace elements. Texturally all the sediments contain high amounts of mud and clay indicating a uniform facies at depths between 30m - 300m. The sediments are a mixture of terrigenous components (albite, K-feldspar, muscovite, quartz, illite, amphibole and biogenic components (calcite, Mgcalcite, aragonite). Pyrite and glauconite are ascribed to diagenesis. There are four distinctive groups of elements each of which includes related elements, derived from different natural sources on land or in the marine basin. The first group (Ca, Sr) reflects the biogenous carbonate fraction and is negatively correlated against every other element determined. A second (Si, Al, Fe, Na, K, Ti, Ba and Zr) group reflects the aluminosilicate minerals derived from the alteration of volcanic rocks, and a third group (Mg, Ni, Cr, C and Zn) reflects the aluminosilicate minerals derived from the alteration of ultrabasic rocks (peridotites) and the organic carbon. The group of Fe, Mn, Zn and Y is a diagenetic association reflecting the distribution of these elements with pyrite. The association of Cu with Zn reflects a mineralization control in the sediment area. Finally, La and Ce are associated with the K-bearing minerals, while P is related to K and Fe-finegrained minerals. The concentrations of heavy metals in the sediments are normal comparing to the contents of other AEGEAN SEA sediments and are due to natural lithogenic sources.","PeriodicalId":173897,"journal":{"name":"Journal of Oceanography and Marine Research","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123912079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Immortal Science of Dead Water: Effects of Internal Wave Drag on Propagating Submerged Bodies 死水的不朽科学:内波阻力对水下传播体的影响

Journal of Oceanography and Marine Research Pub Date : 1900-01-01 DOI: 10.35248/2572-3103.19.7.191

M. Danieletto, Justin M. Brown, T. Radko

{"title":"The Immortal Science of Dead Water: Effects of Internal Wave Drag on Propagating Submerged Bodies","authors":"M. Danieletto, Justin M. Brown, T. Radko","doi":"10.35248/2572-3103.19.7.191","DOIUrl":"https://doi.org/10.35248/2572-3103.19.7.191","url":null,"abstract":"Background: Drag evaluation and prediction are integral to maximizing the efficiency of nautical vehicles. Yet, the total force exerted by a fluid on a body is difficult to predict. One source of drag that remains poorly understood with significant effects for vessels traversing stratified waters is the dead-water phenomenon. It represents the dramatic increase in drag associated with internal waves created by the body itself. This phenomenon has been studied in the literature for surface and submerged vessels separately, but little attention has been given to directly comparing the two. \u0000 \u0000Methods: Our research investigates the dead-water effects by comparing laboratory outcomes for both submerged and surface body experiments in stratified and unstratified fluids. To do this, we tow a cylindrical body with a constant force through a tank of water until the velocity of the towed object becomes uniform, when the drag force balances the towing force. For each scenario, we used four different towing forces. \u0000 \u0000Results: By comparing the drag coefficient measured in each case, we find that the stratified contribution to the drag coefficient is comparable for surface and submerged bodies. The change in the drag coefficient caused by stratification is always positive in these experiments but is much larger for speeds lower than the maximum phase speed of the system. \u0000 \u0000Conclusions: This implies that the dead water modification to the drag coefficient does not depend on the location of the body, which is an important consideration in determining the depth of maximum efficiency for vessel transport.","PeriodicalId":173897,"journal":{"name":"Journal of Oceanography and Marine Research","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132513224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Ecology of the Epiphytic Potentially Harmful Dinoflagellate Ostreopsis cf. ovata (Fukuyo) from Coastal Waters off Alexandria Egypt 埃及亚历山德里亚近海附生潜在有害鞭毛藻Ostreopsis cf. ovata (Fukuyo)的生态学

Journal of Oceanography and Marine Research Pub Date : 1900-01-01 DOI: 10.35248/2572-3103.19.7.189

Shimaa Hosny, W. Labib

引用次数: 5

Photochemical Efficiencies in Reef-Dwelling Anthozoans: Insights from “Survivor” Species 礁栖珊瑚虫的光化学效率:来自“幸存者”物种的见解

Journal of Oceanography and Marine Research Pub Date : 1900-01-01 DOI: 10.35248/2572-3103.19.7.193

Natasha Méndez-Ferrer, P. Hallock

{"title":"Photochemical Efficiencies in Reef-Dwelling Anthozoans: Insights from “Survivor” Species","authors":"Natasha Méndez-Ferrer, P. Hallock","doi":"10.35248/2572-3103.19.7.193","DOIUrl":"https://doi.org/10.35248/2572-3103.19.7.193","url":null,"abstract":"In recent decades, populations of many coral species have declined dramatically on reefs worldwide. A major factor in coral mortality has been photo-oxidative stress associated with both solar irradiance and elevated temperatures. While many studies have focused on species that have declined, fewer efforts have focused on the “survivor” species, those that have maintained relatively stable populations or even increased in abundance. The objective of this study was to assess temporal variability in photochemical efficiencies (Fv/Fm) as an indicator of potential photo-oxidative stress in the dinoflagellate symbionts in three species, the scleractinians Siderastrea siderea and Montastraea cavernosa, and the zoanthid Palythoa caribaeorum, whose populations have remained relatively stable along the Florida reef tract. \u0000 \u0000Coral colonies with no visual indication of disease or bleaching were assessed quarterly in 2012 and 2013, at sites at 6 or 18 m depths. Colonies were dark-acclimated prior to measurements using pulse-amplitude modulated fluorometry. The mean Fv/Fm values for P. caribaeorum colonies assessed at 6 m depth were consistently the lowest (0.59, 0.02 SE). Siderastrea siderea assessed at both 6 and 18 m revealed significantly lower Fv/Fm values (p=0.0006) for those living at 6 m (0.64, 0.02 SE) than for those living at 18 m (0.68, 0.01 SE) depths. The Fv/Fm values for colonies of M. cavernosa assessed at 18 m also averaged 0.68 (0.01 SE). Thus, photochemical efficiencies were lower in colonies living at 6 m than in colonies living at 18 m, while no significant seasonal differences were found in the mean Fv/Fm values in the examined species. This study provides the first known report of photochemical efficiency in P. caribaeorum.","PeriodicalId":173897,"journal":{"name":"Journal of Oceanography and Marine Research","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134577722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Role for Vanadium in Ascidians and in Marine Algae 钒在海鞘和海藻中的作用

Journal of Oceanography and Marine Research Pub Date : 1900-01-01 DOI: 10.35248/2572-3103.19.7.190

D. Rehder

引用次数: 1