T. Harada, Yuki Osumi, Takero Sekimoto, Koki Iyota, Takashi Shiraki, S. Takenaka, H. Takeuchi, Mitsuru Nakajo, T. Tamura
The purpose of this study was to clarify the distribution of oceanic Halobates in the area of the Kuroshio flowing near the southern shore in the direction of 100° - 120°, and also to compare the population density of Halobates between the area within or outside the area of the Kuroshio and also among seasons. This study was carried out during 8 cruises by R/V TANSEIMARU. The Kuroshio area south of the southern Japan coast (30°00'N - 35°00'N, 130°25'E - 141°04'E) was dominated by H. sericeus, and the averaged population-density of this species was significantly higher inside the Kuroshio than outside this current. On the Kuroshio, H. sericeus was dominant with the population density of 16,396.4 km-2 ± 66,138.4 [26] (Mean ± SD [n]), whereas the density of H. germanus was 8,581.9 km-2 ± 24,443.2 [26]. The two oceanic sea skaters, H. sericeusand H. germanus showed significant seasonal variation in the population density, with significantly higher density in October than other months, whereas there was no such significant October peak in the cosmopolitan oceanic sea skater, H. micans. The results of this study may suggest that H. sericeus could use the Kuroshio as a transportation tool to distribute a wide latitude area of from 10°N to 40°N in the western tropical, subtropical and temperate area in the Pacific Ocean.
{"title":"The Distribution of the Oceanic Sea Skaters, Halobates inside and outside the Kuroshio","authors":"T. Harada, Yuki Osumi, Takero Sekimoto, Koki Iyota, Takashi Shiraki, S. Takenaka, H. Takeuchi, Mitsuru Nakajo, T. Tamura","doi":"10.4236/OJMS.2017.73030","DOIUrl":"https://doi.org/10.4236/OJMS.2017.73030","url":null,"abstract":"The purpose of this study was to clarify the distribution of oceanic Halobates in the area of the Kuroshio flowing near the southern shore in the direction of 100° - 120°, and also to compare the population density of Halobates between the area within or outside the area of the Kuroshio and also among seasons. This study was carried out during 8 cruises by R/V TANSEIMARU. The Kuroshio area south of the southern Japan coast (30°00'N - 35°00'N, 130°25'E - 141°04'E) was dominated by H. sericeus, and the averaged population-density of this species was significantly higher inside the Kuroshio than outside this current. On the Kuroshio, H. sericeus was dominant with the population density of 16,396.4 km-2 ± 66,138.4 [26] (Mean ± SD [n]), whereas the density of H. germanus was 8,581.9 km-2 ± 24,443.2 [26]. The two oceanic sea skaters, H. sericeusand H. germanus showed significant seasonal variation in the population density, with significantly higher density in October than other months, whereas there was no such significant October peak in the cosmopolitan oceanic sea skater, H. micans. The results of this study may suggest that H. sericeus could use the Kuroshio as a transportation tool to distribute a wide latitude area of from 10°N to 40°N in the western tropical, subtropical and temperate area in the Pacific Ocean.","PeriodicalId":65849,"journal":{"name":"海洋科学期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44036654","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}
A. Hernández-Pérez, J. A. Zamora-Briseño, J. Vega, Richard Juan de Dios Mena-Loria, Daniel Coronado-Molina, J. Hernández‐López, Norma Angelica-López-Téllez, R. Rodríguez-Canul
A survey for Infectious Hypodermal and Haematopoietic Necrosis Virus (IHHNV) and White Spot Syndrome Virus (WSSV) was performed during two catching seasons of native shrimps in the Yucatan Coast in the Gulf of Mexico. The mtDNA COI barcode identified two endemic species; the southern pink shrimp Penaeus notialis (Perez Fantante, 1967) and the northern pink shrimp Penaeus brasiliensis (Latreille, 1987) (previously described as Farfantepenaeus brasiliensis). The prevalence of IHHNV was of 18.18% in 2016, and of 8.57% in 2017. All organisms tested negative for WSSV. This is the first identification of wild shrimps in the state of Yucatan Mexico by mtDNA COI barcode as well as the first identification of IHHNV in such species. The presence of IHHNV in wild shrimps populations has a potential of persisting in the coast of Yucatan with putative detrimental effect on local fisheries because once established in natural waters and hosts; such pathogens are almost impossible to eradicate.
{"title":"Presence of Infectious Hypodermal and Haematopoietic Necrosis Virus (IHHNV) in Native Shrimps from Southern Mexico","authors":"A. Hernández-Pérez, J. A. Zamora-Briseño, J. Vega, Richard Juan de Dios Mena-Loria, Daniel Coronado-Molina, J. Hernández‐López, Norma Angelica-López-Téllez, R. Rodríguez-Canul","doi":"10.4236/OJMS.2017.73029","DOIUrl":"https://doi.org/10.4236/OJMS.2017.73029","url":null,"abstract":"A survey for Infectious Hypodermal and Haematopoietic Necrosis Virus (IHHNV) and White Spot Syndrome Virus (WSSV) was performed during two catching seasons of native shrimps in the Yucatan Coast in the Gulf of Mexico. The mtDNA COI barcode identified two endemic species; the southern pink shrimp Penaeus notialis (Perez Fantante, 1967) and the northern pink shrimp Penaeus brasiliensis (Latreille, 1987) (previously described as Farfantepenaeus brasiliensis). The prevalence of IHHNV was of 18.18% in 2016, and of 8.57% in 2017. All organisms tested negative for WSSV. This is the first identification of wild shrimps in the state of Yucatan Mexico by mtDNA COI barcode as well as the first identification of IHHNV in such species. The presence of IHHNV in wild shrimps populations has a potential of persisting in the coast of Yucatan with putative detrimental effect on local fisheries because once established in natural waters and hosts; such pathogens are almost impossible to eradicate.","PeriodicalId":65849,"journal":{"name":"海洋科学期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45459632","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}
Jun Li, Bangqi Hu, Jingtao Zhao, F. Bai, Yanguang Dou, Libo Wang, Liang Zou, Xue Ding
Natural radioactivity is very important for the assessment of the marine sand property and usability. By using gamma spectrometry, the concentration of the natural radionuclides 226Ra, 232Th and 40K have been measured in marine sand deposits from Liaodong Bay (LDB), North Yellow Sea (NYS), Zhoushan area (ZS), Taiwan Shoal (TS) and Pearl River Mouth (PR), offshore China, which are potential marine sand mining areas. The radiation activity equivalent (Raeq), indoor gamma absorbed dose rate (DR), annual effective dose (HR), alpha index (Ia), gamma index (Ig), external radiation hazard index (Hex), internal radiation hazard index (Hin), representative level index (RLI), excess lifetime cancer risk (ELCR) and annual gonadal dose equivalent (AGDE) associated with the natural radionuclides are calculated to assess the radiation hazard of the natural radioactivity in the marine sands offshore China. From the analysis, it is found that these marine sands are safe for the constructions. The Pearson correlation coefficient reveals that the 226Ra distribution in the marine sands offshore China is controlled by the variation of the 40K concentration. Principal component analysis (PCA) yields a two-component representation of the entire data from the marine sands, wherein 98.22% of the total variance is explained. Our results provide good baseline data to expand the database of radioactivity of building materials in China and all over the world.
{"title":"Evaluation of Natural Radioactivity in Marine Sand Deposits from Offshore China","authors":"Jun Li, Bangqi Hu, Jingtao Zhao, F. Bai, Yanguang Dou, Libo Wang, Liang Zou, Xue Ding","doi":"10.4236/OJMS.2017.73026","DOIUrl":"https://doi.org/10.4236/OJMS.2017.73026","url":null,"abstract":"Natural radioactivity is very important for the assessment of the marine sand property and usability. By using gamma spectrometry, the concentration of the natural radionuclides 226Ra, 232Th and 40K have been measured in marine sand deposits from Liaodong Bay (LDB), North Yellow Sea (NYS), Zhoushan area (ZS), Taiwan Shoal (TS) and Pearl River Mouth (PR), offshore China, which are potential marine sand mining areas. The radiation activity equivalent (Raeq), indoor gamma absorbed dose rate (DR), annual effective dose (HR), alpha index (Ia), gamma index (Ig), external radiation hazard index (Hex), internal radiation hazard index (Hin), representative level index (RLI), excess lifetime cancer risk (ELCR) and annual gonadal dose equivalent (AGDE) associated with the natural radionuclides are calculated to assess the radiation hazard of the natural radioactivity in the marine sands offshore China. From the analysis, it is found that these marine sands are safe for the constructions. The Pearson correlation coefficient reveals that the 226Ra distribution in the marine sands offshore China is controlled by the variation of the 40K concentration. Principal component analysis (PCA) yields a two-component representation of the entire data from the marine sands, wherein 98.22% of the total variance is explained. Our results provide good baseline data to expand the database of radioactivity of building materials in China and all over the world.","PeriodicalId":65849,"journal":{"name":"海洋科学期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46114214","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}
West African Ilisha was the third most abundant species of Clupeidae off Benin coastal waters after Sardinella spp and Ethmalosa frimbriata. The fishing effort of these fisheries increased with a dominance of small-sized specimens in the catches. This paper allowed updating some demographic parameters and the exploitation rate of Ilisha africana collected between July 2013 and June 2014 from the coastal waters of Benin for management and conservation of these fisheries. The growth pattern showed a negative allometric growth with an abundance of small-sized specimens. The von Bertalanffy growth function (VBGF) estimations were: L∞= 21.31 cm standard length; K = 1.20 year-1; and t0 = -0.138 year. The total mortality rate (Z), natural mortality rate (M) and fishing mortality rate (F) were 4.040 year-1, 2.27 year-1 and 1.77 year-1 respectively. The Z/K ratio was 3.667 and the exploitation rate (E = F/Z) was 0.44 showing an under exploitation of this species. The estimated potential longevity (tmax) was 2.5 years. In addition, the fisheries management should be devolved from the state to the local level to compel fishermen to take greater responsibility for the sustainability and conservation of the fisheries such as size-limit regulation by gradually increasing fishing gears mesh size.
{"title":"Growth, Mortality Parameters and Exploitation Rate of West African Ilisha ( Ilisha africana Bloch, 1795, Clupeidae) off Benin Coastal Waters (West Africa): Implications for Management and Conservation","authors":"S. Edmond, Azonningbo S. H. Wilfrid, F. Didier","doi":"10.4236/OJMS.2017.73024","DOIUrl":"https://doi.org/10.4236/OJMS.2017.73024","url":null,"abstract":"West African Ilisha was the third most abundant species of Clupeidae off Benin coastal waters after Sardinella spp and Ethmalosa frimbriata. The fishing effort of these fisheries increased with a dominance of small-sized specimens in the catches. This paper allowed updating some demographic parameters and the exploitation rate of Ilisha africana collected between July 2013 and June 2014 from the coastal waters of Benin for management and conservation of these fisheries. The growth pattern showed a negative allometric growth with an abundance of small-sized specimens. The von Bertalanffy growth function (VBGF) estimations were: L∞= 21.31 cm standard length; K = 1.20 year-1; and t0 = -0.138 year. The total mortality rate (Z), natural mortality rate (M) and fishing mortality rate (F) were 4.040 year-1, 2.27 year-1 and 1.77 year-1 respectively. The Z/K ratio was 3.667 and the exploitation rate (E = F/Z) was 0.44 showing an under exploitation of this species. The estimated potential longevity (tmax) was 2.5 years. In addition, the fisheries management should be devolved from the state to the local level to compel fishermen to take greater responsibility for the sustainability and conservation of the fisheries such as size-limit regulation by gradually increasing fishing gears mesh size.","PeriodicalId":65849,"journal":{"name":"海洋科学期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41923152","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}
Coastal pollution assessment is a pressing matter as the anthropogenic pressure continues to increase worldwide. A leading approach to assess coastal pollution is using bioindicators. However, identifying species is time-consuming and demands profound morphological knowledge. Our goal was to find the meiobenthic composition in each pollution level. By utilizing the meiobenthic assemblage’s ratios, we will be able to indicate the pollution level. We examined the meiobenthos distribution at three sites exposed to a pollution gradient. We quantified the changes in the fauna assemblage in the community phylum level, focusing on nematodes and foraminifera (90% of the total population). Over 400 samples were examined, covering an annual seasonal cycle. Nematodes population dominated in the polluted coast. Nematodes density increased with the pollution level, up to seemingly harmful levels of pollution. In contradiction, the foraminifera flourished in the control site and exhibited an inverse relationship to the nematodes. We witnessed drastic changes in the entire meiobenthic population in the winter, which we speculate that originated from winter turbulences. We suggest that nematodes-foraminifers’ population ratios may be utilized as bioindicators for assessing coast intertidal zone pollution levels.
{"title":"Meiobenthos Assemblages as Bioindicators for Coastal Pollution Assessment","authors":"Tzachy Y. Morad, Z. Dubinsky, D. Iluz","doi":"10.4236/OJMS.2017.73028","DOIUrl":"https://doi.org/10.4236/OJMS.2017.73028","url":null,"abstract":"Coastal pollution assessment is a pressing matter as the anthropogenic pressure continues to increase worldwide. A leading approach to assess coastal pollution is using bioindicators. However, identifying species is time-consuming and demands profound morphological knowledge. Our goal was to find the meiobenthic composition in each pollution level. By utilizing the meiobenthic assemblage’s ratios, we will be able to indicate the pollution level. We examined the meiobenthos distribution at three sites exposed to a pollution gradient. We quantified the changes in the fauna assemblage in the community phylum level, focusing on nematodes and foraminifera (90% of the total population). Over 400 samples were examined, covering an annual seasonal cycle. Nematodes population dominated in the polluted coast. Nematodes density increased with the pollution level, up to seemingly harmful levels of pollution. In contradiction, the foraminifera flourished in the control site and exhibited an inverse relationship to the nematodes. We witnessed drastic changes in the entire meiobenthic population in the winter, which we speculate that originated from winter turbulences. We suggest that nematodes-foraminifers’ population ratios may be utilized as bioindicators for assessing coast intertidal zone pollution levels.","PeriodicalId":65849,"journal":{"name":"海洋科学期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44788971","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}
Given the socio-economic consequences associated with declaring areas of ocean protected in order to achieve conservation objectives, this paper contributes to the growing global need to assess Marine Protected Areas (MPAs) as an effective management tool. It adds to the current body of knowledge on MPA effectiveness by conducting an evaluation of the Tobago Cays Marine Park (TCMP), located in St. Vincent and the Grenadines (SVG) in the eastern Caribbean, using a modified MPA effectiveness framework. Due to the limited information existing about the current performance of this MPA, this assessment also provides needed insight on the effect that the TCMP is having on the marine ecosystem, as well as its overall management performance. By comparing the performance of the MPA over a 10-year span (2007 and 2016), the results indicate that overall, the TCMP could be described as having limited success when key management categories of context, planning, input, process, output and outcomes are evaluated. In particular, efforts dedicated to planning, process and outcomes are assessed as deficient. Furthermore, the analysis revealed that efforts to realize the stated goals relating to conservation, public awareness and public education were being neglected. However, considerable effort was being expended by TCMP staff on achieving the remaining goal focusing on deriving economic benefits from touristic activities in the Park. Preliminary field research examining the effects of the TCMP on the abundance and density of an economically important species, Lobatus gigas, (commonly referred to as the queen conch) showed the TCMP as having no effect towards conch protection. The results and recommendations of this study, combined with continued monitoring of a recommended targeted suite of indicators, could contribute to better-informed adaptive MPA management, leading to progress towards the achievement of the stated goals for the TCMP.
{"title":"Assessing Marine Protected Areas Effectiveness: A Case Study with the Tobago Cays Marine Park","authors":"A. G. Rodríguez, Lucia Fanning","doi":"10.4236/OJMS.2017.73027","DOIUrl":"https://doi.org/10.4236/OJMS.2017.73027","url":null,"abstract":"Given the socio-economic consequences associated with declaring areas of ocean protected in order to achieve conservation objectives, this paper contributes to the growing global need to assess Marine Protected Areas (MPAs) as an effective management tool. It adds to the current body of knowledge on MPA effectiveness by conducting an evaluation of the Tobago Cays Marine Park (TCMP), located in St. Vincent and the Grenadines (SVG) in the eastern Caribbean, using a modified MPA effectiveness framework. Due to the limited information existing about the current performance of this MPA, this assessment also provides needed insight on the effect that the TCMP is having on the marine ecosystem, as well as its overall management performance. By comparing the performance of the MPA over a 10-year span (2007 and 2016), the results indicate that overall, the TCMP could be described as having limited success when key management categories of context, planning, input, process, output and outcomes are evaluated. In particular, efforts dedicated to planning, process and outcomes are assessed as deficient. Furthermore, the analysis revealed that efforts to realize the stated goals relating to conservation, public awareness and public education were being neglected. However, considerable effort was being expended by TCMP staff on achieving the remaining goal focusing on deriving economic benefits from touristic activities in the Park. Preliminary field research examining the effects of the TCMP on the abundance and density of an economically important species, Lobatus gigas, (commonly referred to as the queen conch) showed the TCMP as having no effect towards conch protection. The results and recommendations of this study, combined with continued monitoring of a recommended targeted suite of indicators, could contribute to better-informed adaptive MPA management, leading to progress towards the achievement of the stated goals for the TCMP.","PeriodicalId":65849,"journal":{"name":"海洋科学期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48709357","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}
Esmaeil Hamedi Eynoddin, A. Solgi, M. Pourkermani, A. Matkan, M. Arian
Geomorphic indices are useful tools for studying relative active tectonics of a specific area. In this study, the relative active tectonics of Bozgoush region (NW of Iran) has been investigated based on Geomorphic indices. The studied indexes include: the stream length-gradient (SL), hypsometric integral (Hi), the ratio of valley floor width to valley height (Vf), the shape of the drainage basin (Bs), the sinuosity of mountain front (Smf), asymmetric factor of drainage basin (Af) and transverse topographic symmetry factor (T). In the present study, gathered data from various morphometric indexes of six basins are aggregated, and their obtained result is provided as relative active tectonics of the region or Iat index that shows a proper illustration of the relative active tectonics of the mentioned region. In order to develop a correct analysis of the mentioned area, the AHP (analytic hierarchy process) model with a studied weight, the final overlapped layer of relative tectonics is prepared with applying coefficients. With the comprehensive field studies, evidences like deep valleys, river bed immigration, landslides, sudden change in river cycles and surfaces of faults were found that are in good consistence with obtained data of relative active tectonics of the region. After measuring these indexes, it was found that Aydoghmush and OujanChay basins have a high relative active tectonics. With regard to the obtained results of present study, it seems that Tabriz fault has the most seismic and motional potential in northern basins of the region. In addition, in Aydoghmush basin, in southern part of the region, Qeynarjehchartagh fault has a high active tectonics that according to the estimated values has been identified as an active young structure in the region.
{"title":"Assessment of Relative Active Tectonics in the Bozgoush Basin (SW of Caspian Sea)","authors":"Esmaeil Hamedi Eynoddin, A. Solgi, M. Pourkermani, A. Matkan, M. Arian","doi":"10.4236/OJMS.2017.72016","DOIUrl":"https://doi.org/10.4236/OJMS.2017.72016","url":null,"abstract":"Geomorphic indices are useful tools for studying relative active tectonics of a specific area. In this study, the relative active tectonics of Bozgoush region (NW of Iran) has been investigated based on Geomorphic indices. The studied indexes include: the stream length-gradient (SL), hypsometric integral (Hi), the ratio of valley floor width to valley height (Vf), the shape of the drainage basin (Bs), the sinuosity of mountain front (Smf), asymmetric factor of drainage basin (Af) and transverse topographic symmetry factor (T). In the present study, gathered data from various morphometric indexes of six basins are aggregated, and their obtained result is provided as relative active tectonics of the region or Iat index that shows a proper illustration of the relative active tectonics of the mentioned region. In order to develop a correct analysis of the mentioned area, the AHP (analytic hierarchy process) model with a studied weight, the final overlapped layer of relative tectonics is prepared with applying coefficients. With the comprehensive field studies, evidences like deep valleys, river bed immigration, landslides, sudden change in river cycles and surfaces of faults were found that are in good consistence with obtained data of relative active tectonics of the region. After measuring these indexes, it was found that Aydoghmush and OujanChay basins have a high relative active tectonics. With regard to the obtained results of present study, it seems that Tabriz fault has the most seismic and motional potential in northern basins of the region. In addition, in Aydoghmush basin, in southern part of the region, Qeynarjehchartagh fault has a high active tectonics that according to the estimated values has been identified as an active young structure in the region.","PeriodicalId":65849,"journal":{"name":"海洋科学期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47236360","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}
Active tectonics is an indicator of recent movement of mountains and landscapes evolution for regions affected by current tectonic activity. The Saymareh-Karkheh river basin is located on the Zagros Mountain in the west Iran. The Zagros Mountain is an orogenic belt that is formed by the collision between the Eurasian and Arabian plates during Cenozoic. Active tectonics has analyzed by measurement of six geomorphic indices (hypsometric integral, basin asymmetry factor, basin shape, the stream length-gradient, mountain-front sinuosity and valley floor width-height ratio) which they combined to index of active tectonics (Iat). Based on values of this index, the Saymareh-Karkheh river basin was divided into high (Class 2, 18.8%), moderate (Class 3, 70.3%), and low (Class 4, 10.9%) relative tectonic activity parts. The above results confirm the usefulness of geomorphic analyses for regional assessment of active tectonics they are compatible with differential tectonic activity in the High Zagros and Zagros fold and thrust belt. Also, it was revealed that geomorphic indices and using of GIS technics are very useful to investigation of active tectonics in the mountain areas.
{"title":"Active Tectonics of the Saymareh-Karkheh River Basin (Northwest of Persian Gulf, Iran)","authors":"N. Rahimi, M. Arian, M. Ghorashi","doi":"10.4236/OJMS.2017.72017","DOIUrl":"https://doi.org/10.4236/OJMS.2017.72017","url":null,"abstract":"Active tectonics is an indicator of recent movement of mountains and landscapes evolution for regions affected by current tectonic activity. The Saymareh-Karkheh river basin is located on the Zagros Mountain in the west Iran. The Zagros Mountain is an orogenic belt that is formed by the collision between the Eurasian and Arabian plates during Cenozoic. Active tectonics has analyzed by measurement of six geomorphic indices (hypsometric integral, basin asymmetry factor, basin shape, the stream length-gradient, mountain-front sinuosity and valley floor width-height ratio) which they combined to index of active tectonics (Iat). Based on values of this index, the Saymareh-Karkheh river basin was divided into high (Class 2, 18.8%), moderate (Class 3, 70.3%), and low (Class 4, 10.9%) relative tectonic activity parts. The above results confirm the usefulness of geomorphic analyses for regional assessment of active tectonics they are compatible with differential tectonic activity in the High Zagros and Zagros fold and thrust belt. Also, it was revealed that geomorphic indices and using of GIS technics are very useful to investigation of active tectonics in the mountain areas.","PeriodicalId":65849,"journal":{"name":"海洋科学期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41611137","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}
This paper is built upon the previous developments on lateral earth pressure by providing a series of analytical expressions that may be used to evaluate vertical profiles of the effective stress and the corresponding suction stress under steady-state flow conditions. Suction stress profile is modeled for one layer sand near the ground above the water level under hydrostatic conditions. By definition, the absolute magnitude of suction stress depends on both the magnitude of the effective stress parameter and matric suction itself. Thus, by developing the Rankine’s relations in seismic state, the composing method of active and passive surfaces in sides of unbraced sheet pile is examinated and the effects of soil parameter on those surfaces are evaluated by a similar process. The relations described the quantitative evaluation of lateral earth pressure on sheet pile and the effects of unsaturated layer on bending moment and embedded depth of sheet pile in soil.
{"title":"Evaluation of Unsaturated Layer Effect on Seismic Analysis of Unbraced Sheet Pile Wall","authors":"M. Jahangir, Hadis Soleymani, S. Sadeghi","doi":"10.4236/OJMS.2017.72022","DOIUrl":"https://doi.org/10.4236/OJMS.2017.72022","url":null,"abstract":"This paper is built upon the previous developments on lateral earth pressure by providing a series of analytical expressions that may be used to evaluate vertical profiles of the effective stress and the corresponding suction stress under steady-state flow conditions. Suction stress profile is modeled for one layer sand near the ground above the water level under hydrostatic conditions. By definition, the absolute magnitude of suction stress depends on both the magnitude of the effective stress parameter and matric suction itself. Thus, by developing the Rankine’s relations in seismic state, the composing method of active and passive surfaces in sides of unbraced sheet pile is examinated and the effects of soil parameter on those surfaces are evaluated by a similar process. The relations described the quantitative evaluation of lateral earth pressure on sheet pile and the effects of unsaturated layer on bending moment and embedded depth of sheet pile in soil.","PeriodicalId":65849,"journal":{"name":"海洋科学期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41765261","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}
T. O. Said, M. Mansour, F. El-Sharkawi, Manal A. Mohamed, M. Shreadah
The residual concentrations of HCHs, TC, DDTs, THCs and PCBs were measured in Sparus auratus collected from the eastern and western sectors of the Egyptian Mediterranean Sea, as the most common fish species in the area. Gas chromatograph equipped with 63Ni-electron capture detector and 35% phenyl polysilphenylenesiloxane capillary column was used for the analysis and quantification after well-established extraction techniques. The concentrations (wet weight) of PCBs, DDTs, TCs, HCHs were: (1.87 - 616.66 ng·g-1), (0.42 - 98.28 ng·g-1), (0.06 - 2.94 ng·g-1), (0.35 - 11.77 ng·g-1), respectively in Sparus auratus collected from the eastern sector. However, these concentrations as wet weight in Sparus auratus from the western sector were: (5.75 - 605.53 ng·g-1), (1.53 - 226.47 ng·g-1), (0.09 - 8.12 ng·g-1), (0.26 - 5.80 ng·g-1), respectively. In general, concentrations of pesticides and PCBs in Sparus auratus either from the western or eastern Egyptian Mediterranean coast were far below the international permissible levels.
{"title":"POPs in Sparus auratus Species from the Eastern and Western Egyptian Mediterranean Coast: A Health Hazard Study","authors":"T. O. Said, M. Mansour, F. El-Sharkawi, Manal A. Mohamed, M. Shreadah","doi":"10.4236/OJMS.2017.72023","DOIUrl":"https://doi.org/10.4236/OJMS.2017.72023","url":null,"abstract":"The residual concentrations of HCHs, TC, DDTs, THCs and PCBs were measured in Sparus auratus collected from the eastern and western sectors of the Egyptian Mediterranean Sea, as the most common fish species in the area. Gas chromatograph equipped with 63Ni-electron capture detector and 35% phenyl polysilphenylenesiloxane capillary column was used for the analysis and quantification after well-established extraction techniques. The concentrations (wet weight) of PCBs, DDTs, TCs, HCHs were: (1.87 - 616.66 ng·g-1), (0.42 - 98.28 ng·g-1), (0.06 - 2.94 ng·g-1), (0.35 - 11.77 ng·g-1), respectively in Sparus auratus collected from the eastern sector. However, these concentrations as wet weight in Sparus auratus from the western sector were: (5.75 - 605.53 ng·g-1), (1.53 - 226.47 ng·g-1), (0.09 - 8.12 ng·g-1), (0.26 - 5.80 ng·g-1), respectively. In general, concentrations of pesticides and PCBs in Sparus auratus either from the western or eastern Egyptian Mediterranean coast were far below the international permissible levels.","PeriodicalId":65849,"journal":{"name":"海洋科学期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46480079","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}
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