Pub Date : 2008-05-27DOI: 10.1109/BALTIC.2008.4625541
C. Brockmann, K. Stelzer, M. Viel, A. Mangin, J.V. Tornfeldt-Sorensen, T. Stipa, A. Neumann, H. Krawczyk, A. Pi Figueroa, G. Campbell, J. Bruniquel
The Baltic Sea is subject to various European environmental regulations which aim at securing its long-term protection. This will be achieved by the accompanying monitoring programmes associated with, for example, the HELCOM convention, the EC water framework directive, the natura 2000 Directives and the upcoming European maritime policy, to name the most important regulatory policies. These monitoring programmes demand large scale, frequent and accurate measurements of physical, biological and chemical parameters. GMES (global monitoring for environment and security) is a major activity of the European Union and Commission which aims at providing operational services by making the best use of spaceborne earth observation data, in-situ observations and models. MarCoast is the GMES service element project addressing the marine environment and is funded by the European space agency. MarCoast is providing marine and coastal services for international, regional and national end users. The project is driven solely by these end users, which include mainly public bodies in charge of the marine environment, such as, for example, the European environmental agency (EEA), the European maritime security agency (EMSA) or the German federal and maritime hydrographic agency (BSH). The MarCoast service portfolio includes oil spill detection and polluter identification as well as water quality products and services. The latter comprises monitoring the water quality with respect to European regulations as above, monitoring and alerting of algal blooms and the monitoring of large scale water quality indicators. The production chain of MarCoast begins with ENVISAT MERIS and Aqua MODIS data for the ocean colour products and AATSR data for sea surface temperature. The satellite data are downloaded from the space agencies and routinely processed to provide basic data sets of key parameters on a common grid. A merged MODIS and MERIS data product is produced at 1km. MERIS Full Resolution data (300m) complement the basic data. The service providers combine the basic data with in-situ data, integrate them into forecasting models or perform data analysis and statistical evaluation. Validation plays a key role for the acceptance of the satellite derived products by the end users. The accuracy of the products and the reliability of the service are regularly evaluated by the Validation Bureau, which is an independent entity within the project.
{"title":"Routine water quality services for the Baltic Sea (GMES MarCoast)","authors":"C. Brockmann, K. Stelzer, M. Viel, A. Mangin, J.V. Tornfeldt-Sorensen, T. Stipa, A. Neumann, H. Krawczyk, A. Pi Figueroa, G. Campbell, J. Bruniquel","doi":"10.1109/BALTIC.2008.4625541","DOIUrl":"https://doi.org/10.1109/BALTIC.2008.4625541","url":null,"abstract":"The Baltic Sea is subject to various European environmental regulations which aim at securing its long-term protection. This will be achieved by the accompanying monitoring programmes associated with, for example, the HELCOM convention, the EC water framework directive, the natura 2000 Directives and the upcoming European maritime policy, to name the most important regulatory policies. These monitoring programmes demand large scale, frequent and accurate measurements of physical, biological and chemical parameters. GMES (global monitoring for environment and security) is a major activity of the European Union and Commission which aims at providing operational services by making the best use of spaceborne earth observation data, in-situ observations and models. MarCoast is the GMES service element project addressing the marine environment and is funded by the European space agency. MarCoast is providing marine and coastal services for international, regional and national end users. The project is driven solely by these end users, which include mainly public bodies in charge of the marine environment, such as, for example, the European environmental agency (EEA), the European maritime security agency (EMSA) or the German federal and maritime hydrographic agency (BSH). The MarCoast service portfolio includes oil spill detection and polluter identification as well as water quality products and services. The latter comprises monitoring the water quality with respect to European regulations as above, monitoring and alerting of algal blooms and the monitoring of large scale water quality indicators. The production chain of MarCoast begins with ENVISAT MERIS and Aqua MODIS data for the ocean colour products and AATSR data for sea surface temperature. The satellite data are downloaded from the space agencies and routinely processed to provide basic data sets of key parameters on a common grid. A merged MODIS and MERIS data product is produced at 1km. MERIS Full Resolution data (300m) complement the basic data. The service providers combine the basic data with in-situ data, integrate them into forecasting models or perform data analysis and statistical evaluation. Validation plays a key role for the acceptance of the satellite derived products by the end users. The accuracy of the products and the reliability of the service are regularly evaluated by the Validation Bureau, which is an independent entity within the project.","PeriodicalId":6307,"journal":{"name":"2008 IEEE/OES US/EU-Baltic International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74705166","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}
Pub Date : 2008-05-27DOI: 10.1109/BALTIC.2008.4625509
K. Povidisa, M. Holmer
Iron (Fe) plaque formation is a well known phenomenon in wetland, freshwater and salt marsh species; however there are no reports about Fe plaque occurrence in seagrasses. Here we review the main factors regulating Fe deposition on the roots and rhizomes of plants from reduced sediments/soils, and discuss these factors in relation to marine environment. Moreover, we present some early observations and quantification of Fe plaque on the tropical seagrass Cymodocea serrulata. Based on these first results and literature data, we compare the seagrass C. serrulata with the freshwater macrophyte Lobelia dortmanna performance and efficiency with regard to plaque formation. The comparison shows that regardless of the lower oxygen release to the sediment and less favourable sediment conditions with high pH, low organic matter content, high carbonate content and actively ongoing sulphate reduction, the seagrass is able to develop significant Fe plaques on roots and rhizomes. Thus we conclude that seagrasses have the necessary characteristics for plaque formation, and that marine sediments may be a favourable environment for Fe plaque development. Moreover, we suggest the likelihood of finding Fe deposits also on other species than C. serrulata and in other geographical locations.
{"title":"Iron plaque formation on seagrasses: Why not?","authors":"K. Povidisa, M. Holmer","doi":"10.1109/BALTIC.2008.4625509","DOIUrl":"https://doi.org/10.1109/BALTIC.2008.4625509","url":null,"abstract":"Iron (Fe) plaque formation is a well known phenomenon in wetland, freshwater and salt marsh species; however there are no reports about Fe plaque occurrence in seagrasses. Here we review the main factors regulating Fe deposition on the roots and rhizomes of plants from reduced sediments/soils, and discuss these factors in relation to marine environment. Moreover, we present some early observations and quantification of Fe plaque on the tropical seagrass Cymodocea serrulata. Based on these first results and literature data, we compare the seagrass C. serrulata with the freshwater macrophyte Lobelia dortmanna performance and efficiency with regard to plaque formation. The comparison shows that regardless of the lower oxygen release to the sediment and less favourable sediment conditions with high pH, low organic matter content, high carbonate content and actively ongoing sulphate reduction, the seagrass is able to develop significant Fe plaques on roots and rhizomes. Thus we conclude that seagrasses have the necessary characteristics for plaque formation, and that marine sediments may be a favourable environment for Fe plaque development. Moreover, we suggest the likelihood of finding Fe deposits also on other species than C. serrulata and in other geographical locations.","PeriodicalId":6307,"journal":{"name":"2008 IEEE/OES US/EU-Baltic International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85142599","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}
Pub Date : 2008-05-27DOI: 10.1109/BALTIC.2008.4625537
V. Ryabchenko, I. Neelov, R. Vankevich, A. Isaev, O. Savchuk, T. Eremina
Two simulations of the Baltic Sea state under different nutrient land loads estimated within the MARE and the SEGUE projects were performed with the St. Petersburg Baltic Eutrophication Model (SPBEM) for the period 1996-2000. Comparison of results of these two runs of nutrient land loads showed that the differences in concentrations of biogeochemical characteristics by the end of the period considered are significant in the coastal zone, especially in the vicinity of the major river mouths. This implies that a careful reassessment of nutrient land loads is needed before the implementation of scenario simulations of nutrient load reduction measures.
{"title":"3D modeling the Baltic Sea ecosystem under different land loads","authors":"V. Ryabchenko, I. Neelov, R. Vankevich, A. Isaev, O. Savchuk, T. Eremina","doi":"10.1109/BALTIC.2008.4625537","DOIUrl":"https://doi.org/10.1109/BALTIC.2008.4625537","url":null,"abstract":"Two simulations of the Baltic Sea state under different nutrient land loads estimated within the MARE and the SEGUE projects were performed with the St. Petersburg Baltic Eutrophication Model (SPBEM) for the period 1996-2000. Comparison of results of these two runs of nutrient land loads showed that the differences in concentrations of biogeochemical characteristics by the end of the period considered are significant in the coastal zone, especially in the vicinity of the major river mouths. This implies that a careful reassessment of nutrient land loads is needed before the implementation of scenario simulations of nutrient load reduction measures.","PeriodicalId":6307,"journal":{"name":"2008 IEEE/OES US/EU-Baltic International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77235359","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}
Pub Date : 2008-05-27DOI: 10.1109/BALTIC.2008.4625526
R. Uiboupin, U. Raudsepp, L. Sipelgas
SAR images from the Estonian coastal area were analyzed to identify oil spills. Slicks were detected on five images in February and March 2008. The analysis showed that the slicks occurred on the ship track. Seatrack Web model (SMHI) that includes ship automatic identification (AIS) data provides a possibility to identify the polluters. In two cases the hindcast model together with AIS information system enabled to detect the possible polluters.
{"title":"Detection of oil spills on SAR images, identification of polluters and forecast of the slicks trajectory","authors":"R. Uiboupin, U. Raudsepp, L. Sipelgas","doi":"10.1109/BALTIC.2008.4625526","DOIUrl":"https://doi.org/10.1109/BALTIC.2008.4625526","url":null,"abstract":"SAR images from the Estonian coastal area were analyzed to identify oil spills. Slicks were detected on five images in February and March 2008. The analysis showed that the slicks occurred on the ship track. Seatrack Web model (SMHI) that includes ship automatic identification (AIS) data provides a possibility to identify the polluters. In two cases the hindcast model together with AIS information system enabled to detect the possible polluters.","PeriodicalId":6307,"journal":{"name":"2008 IEEE/OES US/EU-Baltic International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76956296","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}
Pub Date : 2008-05-27DOI: 10.1109/BALTIC.2008.4625497
Anders Jönsson, C. Mörth
The concentration of organic carbon in coastal sediments depends on several inter-related variables in a complex way. However, within a relatively small coastal area, several of these factors vary only little. Under these circumstances one variable, which to the largest extent determines the concentration of organic carbon is the mechanical energy of the bottom sediments. In this study we have collected sediment cores from two types of bottoms, transport (discontinuous deposition of fine particles and lower water content of sediments) and accumulation bottoms (continuous deposition of fine particles and higher water content of sediments), in a small area of the Stockholm Archipelago, in the Baltic Sea. The two bottom types are defined according to the water content of the sediment samples at the surface and distribution with depth. A statistical analysis of the organic concentration data by the means of an Analysis of variance (ANOVA) test with a 2-way layout, showed that the bottom type and not the sediment depth determines the concentration of organic carbon in these sediments. This result is believed to be universal under certain premises, and hence provides a rationale for surveying (with e g acoustic methods) the bottom dynamics whenever an estimate of the organic carbon concentration in the sediments of a given coastal area is desired. If the mean organic carbon concentration is estimated by considering these two sub-populations instead of a simple estimate, a smaller error will be obtained.
{"title":"Regional spatial distributions of organic carbon in coastal surface sediments of the Baltic Sea - A statistical approach and a rationale for geophysical surveying","authors":"Anders Jönsson, C. Mörth","doi":"10.1109/BALTIC.2008.4625497","DOIUrl":"https://doi.org/10.1109/BALTIC.2008.4625497","url":null,"abstract":"The concentration of organic carbon in coastal sediments depends on several inter-related variables in a complex way. However, within a relatively small coastal area, several of these factors vary only little. Under these circumstances one variable, which to the largest extent determines the concentration of organic carbon is the mechanical energy of the bottom sediments. In this study we have collected sediment cores from two types of bottoms, transport (discontinuous deposition of fine particles and lower water content of sediments) and accumulation bottoms (continuous deposition of fine particles and higher water content of sediments), in a small area of the Stockholm Archipelago, in the Baltic Sea. The two bottom types are defined according to the water content of the sediment samples at the surface and distribution with depth. A statistical analysis of the organic concentration data by the means of an Analysis of variance (ANOVA) test with a 2-way layout, showed that the bottom type and not the sediment depth determines the concentration of organic carbon in these sediments. This result is believed to be universal under certain premises, and hence provides a rationale for surveying (with e g acoustic methods) the bottom dynamics whenever an estimate of the organic carbon concentration in the sediments of a given coastal area is desired. If the mean organic carbon concentration is estimated by considering these two sub-populations instead of a simple estimate, a smaller error will be obtained.","PeriodicalId":6307,"journal":{"name":"2008 IEEE/OES US/EU-Baltic International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80584268","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}
Pub Date : 2008-05-27DOI: 10.1109/BALTIC.2008.4625486
O. Schofield, J. Kohut, H. Roarty, S. Glenn, C. Jones, D. Webb
Buoyancy driven Slocum Gliders were a vision of Douglas Webb, which Henry Stommel championed in a futuristic vision published in 1989. Slocum Gliders have transitioned from a concept to a technology serving basic research and environmental stewardship. The long duration and low operating costs of Gliders allow them to anchor spatial time series. Large distances, over 600 kilometers, can be covered using a single set of alkaline batteries. Since the initial tests, a wide range of physical and optical sensors have been integrated into the Glider allowing measurements of temperature, salinity, depth averaged currents, surface currents, fluorescence, apparent and inherent optical properties. The ability to operate Gliders for extended periods of time are making them the central in situ technology for the evolving ocean observatories. Off shore New Jersey Gliders have occupied a cross shelf transect and have documented the annual variability in shelf wide stratification on the Mid-Atlantic Bight and the role of storms in sediment resuspension. The sustained data permit scientists to gather regional data critical to addressing if, and how, the oceans are changing. One of next major regions we will use this technology is to study the climate induced impacts on the food webs along the West Antarctic Peninsula.
{"title":"Enabling discovery based science with Webb Gliders","authors":"O. Schofield, J. Kohut, H. Roarty, S. Glenn, C. Jones, D. Webb","doi":"10.1109/BALTIC.2008.4625486","DOIUrl":"https://doi.org/10.1109/BALTIC.2008.4625486","url":null,"abstract":"Buoyancy driven Slocum Gliders were a vision of Douglas Webb, which Henry Stommel championed in a futuristic vision published in 1989. Slocum Gliders have transitioned from a concept to a technology serving basic research and environmental stewardship. The long duration and low operating costs of Gliders allow them to anchor spatial time series. Large distances, over 600 kilometers, can be covered using a single set of alkaline batteries. Since the initial tests, a wide range of physical and optical sensors have been integrated into the Glider allowing measurements of temperature, salinity, depth averaged currents, surface currents, fluorescence, apparent and inherent optical properties. The ability to operate Gliders for extended periods of time are making them the central in situ technology for the evolving ocean observatories. Off shore New Jersey Gliders have occupied a cross shelf transect and have documented the annual variability in shelf wide stratification on the Mid-Atlantic Bight and the role of storms in sediment resuspension. The sustained data permit scientists to gather regional data critical to addressing if, and how, the oceans are changing. One of next major regions we will use this technology is to study the climate induced impacts on the food webs along the West Antarctic Peninsula.","PeriodicalId":6307,"journal":{"name":"2008 IEEE/OES US/EU-Baltic International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88514512","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}
Pub Date : 2008-05-27DOI: 10.1109/BALTIC.2008.4625498
A. Clark
The development and implementation of ocean observatories has primarily been driven by the research community and academic institutions. National governments have begun to take an increasingly more active role both in terms of fostering the development of individual observatories (the National Science Foundationpsilas Ocean Observatory Initiative) as well as the consideration of linking these individual observatories together into a national network (the Ocean.US Integrated Ocean Observing System). The role to be played by the private sector, both large and small companies, is also beginning to emerge. This paper explores some of the activities already undertaken by industry in ocean observing initiatives in the U.S. and other international initiatives.
{"title":"Ocean observing technology and public-private partnerships","authors":"A. Clark","doi":"10.1109/BALTIC.2008.4625498","DOIUrl":"https://doi.org/10.1109/BALTIC.2008.4625498","url":null,"abstract":"The development and implementation of ocean observatories has primarily been driven by the research community and academic institutions. National governments have begun to take an increasingly more active role both in terms of fostering the development of individual observatories (the National Science Foundationpsilas Ocean Observatory Initiative) as well as the consideration of linking these individual observatories together into a national network (the Ocean.US Integrated Ocean Observing System). The role to be played by the private sector, both large and small companies, is also beginning to emerge. This paper explores some of the activities already undertaken by industry in ocean observing initiatives in the U.S. and other international initiatives.","PeriodicalId":6307,"journal":{"name":"2008 IEEE/OES US/EU-Baltic International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88699251","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}
Pub Date : 2008-05-27DOI: 10.1109/BALTIC.2008.4625508
T. McGee, J. Woolsey, L. Macelloni, B. Battista, S. Caruso, L. Lapham, V. Goebel, J. Carrol
The Gulf of Mexico hydrates research consortium has been designing a sea-floor observatory to monitor natural gas hydrates in the gulf of Mexico for almost ten years. The observatory will consist of seismo-acoustic receiving arrays, geochemical arrays in the lower water column and upper sediments as well as systems for observing microbial activity. Mississippi Canyon Lease Block 118 (MC118) in the northern part of the Gulf has been selected as the site of the observatory. A carbonate/hydrate mound approximately one kilometer in diameter occurs in the south-central portion of MC118 at a water depth of about 900 m. The surface morphology of the mound has been imaged by multi-beam bathymetric sonar from an autonomous underwater vehicle (AUV) operating 40 m above the sea floor, by video cameras deployed on and a few meters above the sea floor from surface vessels and by visual observations from manned submarines. Gravity and box cores have been collected for lithologic and bio-geochemical studies of the near-surface sediments on the mound. Microbial sulfate reduction, anaerobic methane oxidation, and methanogenesis are all important processes in the upper four meters of sediment. These microbial processes seem to control the diffusive flux of methane from the sediments into the overlying water column. The activity of microbes is also focused within patches or dasiahot spotspsila at the main, active mounds. This activity is primarily dependent upon an active fluid flux of hydrocarbon-rich fluids. The geochemical evidence suggests that the fluid flux waxes and wanes over time and that the microbial activity is sensitive to such change. The subsurface structure of the mound has been investigated by chirp-sonar profiles acquired by the AUV simultaneously with acquisition of the swath bathymetry data and by a psuedo-3D grid of high-resolution seismic profiles obtained using the surface-source/deep-receiver technique. Also, deep seismic 3D volumes obtained by the petroleum industry have been viewed. The surface of the mound is pocked by craters apparently formed during episodic fluid expulsion events. Gases venting from the mound, as well as those contained in outcropping hydrates, have been analyzed and found to be thermogenic, perhaps having migrated up faults from a deep, as yet undiscovered, petroleum reservoir. The deep seismic data show that the faults emanate from a salt diapir located some hundreds of meters below the mound. It was observed during a cruise in November, 2007, that craters and outcrops had changed significantly during the 14-month period since the previous cruise in September, 2006. The mound therefore has been shown to be sufficiently dynamic to warrant continuous monitoring over the five-to-ten years that the observatory is expected to be operational.
{"title":"Progress toward a sea-floor observatory at a carbonate/hydrate mound in the northern Gulf of Mexico","authors":"T. McGee, J. Woolsey, L. Macelloni, B. Battista, S. Caruso, L. Lapham, V. Goebel, J. Carrol","doi":"10.1109/BALTIC.2008.4625508","DOIUrl":"https://doi.org/10.1109/BALTIC.2008.4625508","url":null,"abstract":"The Gulf of Mexico hydrates research consortium has been designing a sea-floor observatory to monitor natural gas hydrates in the gulf of Mexico for almost ten years. The observatory will consist of seismo-acoustic receiving arrays, geochemical arrays in the lower water column and upper sediments as well as systems for observing microbial activity. Mississippi Canyon Lease Block 118 (MC118) in the northern part of the Gulf has been selected as the site of the observatory. A carbonate/hydrate mound approximately one kilometer in diameter occurs in the south-central portion of MC118 at a water depth of about 900 m. The surface morphology of the mound has been imaged by multi-beam bathymetric sonar from an autonomous underwater vehicle (AUV) operating 40 m above the sea floor, by video cameras deployed on and a few meters above the sea floor from surface vessels and by visual observations from manned submarines. Gravity and box cores have been collected for lithologic and bio-geochemical studies of the near-surface sediments on the mound. Microbial sulfate reduction, anaerobic methane oxidation, and methanogenesis are all important processes in the upper four meters of sediment. These microbial processes seem to control the diffusive flux of methane from the sediments into the overlying water column. The activity of microbes is also focused within patches or dasiahot spotspsila at the main, active mounds. This activity is primarily dependent upon an active fluid flux of hydrocarbon-rich fluids. The geochemical evidence suggests that the fluid flux waxes and wanes over time and that the microbial activity is sensitive to such change. The subsurface structure of the mound has been investigated by chirp-sonar profiles acquired by the AUV simultaneously with acquisition of the swath bathymetry data and by a psuedo-3D grid of high-resolution seismic profiles obtained using the surface-source/deep-receiver technique. Also, deep seismic 3D volumes obtained by the petroleum industry have been viewed. The surface of the mound is pocked by craters apparently formed during episodic fluid expulsion events. Gases venting from the mound, as well as those contained in outcropping hydrates, have been analyzed and found to be thermogenic, perhaps having migrated up faults from a deep, as yet undiscovered, petroleum reservoir. The deep seismic data show that the faults emanate from a salt diapir located some hundreds of meters below the mound. It was observed during a cruise in November, 2007, that craters and outcrops had changed significantly during the 14-month period since the previous cruise in September, 2006. The mound therefore has been shown to be sufficiently dynamic to warrant continuous monitoring over the five-to-ten years that the observatory is expected to be operational.","PeriodicalId":6307,"journal":{"name":"2008 IEEE/OES US/EU-Baltic International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89310802","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}
Pub Date : 2008-05-27DOI: 10.1109/BALTIC.2008.4625566
S. Golubkov
Long-term fluctuations in composition, biomass and functional patterns of benthic animal communities in Neva Bay, which became freshwater artificial lagoon in the middle 1980s due to construction of flood protection barrier (Dam), are depended on both natural and anthropogenic factors. The influence of natural climatic induced factors is evinced by periodic high increase in zoobenthic biomass with a dominance of small mollusks, Pisidiidae, in the eastern part of the bay near the delta of Neva River (the area with highest sedimentation rate of particulate organic matter) for the years of high run-of of Neva River. It is periodically succeeded by dominance of large mollusks, Unionidae, in the other parts of Neva Bay in the years of low run-of of Neva River. Progressive decrease in abundance of glacial relicts, Pallasea quadrispinosa, and increase of Oligochaeta worms was observed since the beginning of 20th Century probably due to an increase of eutrophication and organic pollution in the bay. Functional role of zoobenthic communities in decomposition of organic matter and regeneration of phosphorus in the bay was very high at the beginning of 1980psilas in the period of high river run-of. In that time their food consumption was much higher than primary production in Neva Bay and they decomposed the main portion of the particulate organic matter brought by the Neva River waters. The role of zoobenthos in decomposition of organic matter has decreased during the last two decades in a period of low run-of due to the shift of the dominance of small Pisidiidae to large Unionidae and increase of plankton primary production in the bay. Large scale digging and dumping of bottom sediments dealing with constructions of new lands and ports in the eastern part of Neva Bay, which began in 2006 and resulted in distribution of great amount of suspended particulate matters over the whole bay, negatively affects bottom animal communities decreasing their role in ldquomarginal filterrdquo of the Neva Estuary.
{"title":"Factors affecting the role of macrobenthos in pelagic-benthic coupling in the Neva Bay (eastern Gulf of Finland)","authors":"S. Golubkov","doi":"10.1109/BALTIC.2008.4625566","DOIUrl":"https://doi.org/10.1109/BALTIC.2008.4625566","url":null,"abstract":"Long-term fluctuations in composition, biomass and functional patterns of benthic animal communities in Neva Bay, which became freshwater artificial lagoon in the middle 1980s due to construction of flood protection barrier (Dam), are depended on both natural and anthropogenic factors. The influence of natural climatic induced factors is evinced by periodic high increase in zoobenthic biomass with a dominance of small mollusks, Pisidiidae, in the eastern part of the bay near the delta of Neva River (the area with highest sedimentation rate of particulate organic matter) for the years of high run-of of Neva River. It is periodically succeeded by dominance of large mollusks, Unionidae, in the other parts of Neva Bay in the years of low run-of of Neva River. Progressive decrease in abundance of glacial relicts, Pallasea quadrispinosa, and increase of Oligochaeta worms was observed since the beginning of 20th Century probably due to an increase of eutrophication and organic pollution in the bay. Functional role of zoobenthic communities in decomposition of organic matter and regeneration of phosphorus in the bay was very high at the beginning of 1980psilas in the period of high river run-of. In that time their food consumption was much higher than primary production in Neva Bay and they decomposed the main portion of the particulate organic matter brought by the Neva River waters. The role of zoobenthos in decomposition of organic matter has decreased during the last two decades in a period of low run-of due to the shift of the dominance of small Pisidiidae to large Unionidae and increase of plankton primary production in the bay. Large scale digging and dumping of bottom sediments dealing with constructions of new lands and ports in the eastern part of Neva Bay, which began in 2006 and resulted in distribution of great amount of suspended particulate matters over the whole bay, negatively affects bottom animal communities decreasing their role in ldquomarginal filterrdquo of the Neva Estuary.","PeriodicalId":6307,"journal":{"name":"2008 IEEE/OES US/EU-Baltic International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90513846","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}
Pub Date : 2008-05-27DOI: 10.1109/BALTIC.2008.4625510
T. Missiaen, P. Feller
Very high resolution seismic and magnetic investigations were carried out over a chemical munition dumpsite in the Bornholm Basin, south-western Baltic. The main goal of the investigations was to image the internal structure of the dumpsite and to map the lateral and vertical distribution of the dumped weapons. The shallow geology was imaged in great detail on the seismic data. Seven seismic-stratigraphic units were identified, related to different stages in the Holocene and late-glacial history. A large number of diapir-like features were observed that most likely represent fluid expulsion phenomena. Four shipwrecks were identified in the dumpsite area. The wrecks have partly sunk into the soft upper sediments, their height above the sea floor reaching no more than 2 m. Seismic and magnetic data indicate the presence of a large number of buried objects. In most cases there is a good correlation between the two data sets. The objects are generally buried no deeper than 1 to 2 m. Their size varies between 1.5 and 5 m, occasionally up to 10 m. Shallow pits in the sea bed are likely due to the impact of dumping. The data confirm the wide variety of dumped war material ranging from bombs and shells to encasements and containers. The distribution of the buried objects seems rather heterogeneous, with locally high object concentrations surrounded by areas of lower object density. The results of this case study demonstrate the benefit of complementary, concurrent geophysical investigations for munition dumpsite research. Finally this will yield a better assessment of the current status of the dumpsite and the possible ecological risks related to the dumped war material.
{"title":"Geophysical investigations of a chemical munition dumpsite in the Baltic Sea","authors":"T. Missiaen, P. Feller","doi":"10.1109/BALTIC.2008.4625510","DOIUrl":"https://doi.org/10.1109/BALTIC.2008.4625510","url":null,"abstract":"Very high resolution seismic and magnetic investigations were carried out over a chemical munition dumpsite in the Bornholm Basin, south-western Baltic. The main goal of the investigations was to image the internal structure of the dumpsite and to map the lateral and vertical distribution of the dumped weapons. The shallow geology was imaged in great detail on the seismic data. Seven seismic-stratigraphic units were identified, related to different stages in the Holocene and late-glacial history. A large number of diapir-like features were observed that most likely represent fluid expulsion phenomena. Four shipwrecks were identified in the dumpsite area. The wrecks have partly sunk into the soft upper sediments, their height above the sea floor reaching no more than 2 m. Seismic and magnetic data indicate the presence of a large number of buried objects. In most cases there is a good correlation between the two data sets. The objects are generally buried no deeper than 1 to 2 m. Their size varies between 1.5 and 5 m, occasionally up to 10 m. Shallow pits in the sea bed are likely due to the impact of dumping. The data confirm the wide variety of dumped war material ranging from bombs and shells to encasements and containers. The distribution of the buried objects seems rather heterogeneous, with locally high object concentrations surrounded by areas of lower object density. The results of this case study demonstrate the benefit of complementary, concurrent geophysical investigations for munition dumpsite research. Finally this will yield a better assessment of the current status of the dumpsite and the possible ecological risks related to the dumped war material.","PeriodicalId":6307,"journal":{"name":"2008 IEEE/OES US/EU-Baltic International Symposium","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73886225","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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