Common sole in the northern and central Adriatic Sea: Spatial management scenarios to rebuild the stock

Science.gov (United States)

Scarcella, Giuseppe; Grati, Fabio; Raicevich, Saša; Russo, Tommaso; Gramolini, Roberto; Scott, Robert D.; Polidori, Piero; Domenichetti, Filippo; Bolognini, Luca; Giovanardi, Otello; Celić, Igor; Sabatini, Laura; Vrgoč, Nedo; Isajlović, Igor; Marčeta, Bojan; Fabi, Gianna

2014-05-01

The northern and central Adriatic Sea represents an important spawning and aggregation area for common sole (Solea solea) and provides for around 20% of the Mediterranean landings. In this area, this resource is mainly exploited with rapido trawl and set nets. The stock is not yet depleted and faces a situation of growth overfishing. The comparison between the spatial distribution by age of S. solea and the geographic patterns of the rapido trawl fishing effort evidenced an overlapping of this fishing activity with the area where juveniles concentrate (age groups 0-2). The majority of spawners inhabits specific offshore areas, here defined as ‘sole sanctuaries', where high concentrations of debris and benthic communities make difficult trawling with rapido. The aim of this study was to evaluate existing spatial management regimes and potential new spatial and temporal closures in the northern and central Adriatic Sea using a simple modelling tool. Two spatial simulations were carried out in order to verify the effectiveness of complementary methods for the management of fisheries: the ban of rapido trawling from October to December within 6 nautical miles and 9 nautical miles of the Italian coast. The focus of the simulation is that the effort of the rapido trawl is moved far from the coast during key sole recruitment periods, when the juveniles are moving from the inshore nursery area toward the offshore feeding grounds. The management scenarios showed that a change in selectivity would lead to a clear increase in the spawning stock biomass and an increase in landings of S. solea in the medium-term. The rapido trawl activity could be managed by using a different logic, bearing in mind that catches and incomes would increase with small changes in the spatial pattern of the fishing effort. The present study highlights the importance of taking into account spatial dimensions of fishing fleets and the possible interactions that can occur between fleets and target

Elasmobranch bycatch in the Italian Adriatic pelagic trawl fishery

Science.gov (United States)

Fortuna, Caterina Maria; Moro, Fabrizio; Sala, Antonello

2018-01-01

Elasmobranchs are among the most threatened long-lived marine species worldwide, and incidental capture is a major source of mortality. The northern central Adriatic Sea, though one of the most overfished basins of the Mediterranean Sea, supports a very valuable marine biodiversity, including elasmobranchs. This study assesses the impact of the northern central Adriatic pelagic trawl fishery on common smooth-hound (Mustelus mustelus), spiny dogfish (Squalus acanthias), common eagle ray (Myliobatis aquila), and pelagic stingray (Pteroplatytrygon violacea) by examining incidental catches recorded between 2006 and 2015. The distribution of bycatch events was evaluated using geo-referenced data. Generalized Linear Models were computed to standardize the catch of the four species and to predict the relative abundance of bycatch events. Data analysis shows that most bycatch events involving all four species occurred in the northern Adriatic Sea. The models predicted significant, distinct temporal patterns of standardized catches in line with previous investigations. Water depth, season, and fishing region were the best predictors to explain bycatch events. The present data suggest that the northern Adriatic may be an important nursery area for several elasmobranchs. They also highlight the urgent need for a better understanding of the interactions between elasmobranchs and fisheries to develop and apply suitable, ad hoc management measures. PMID:29377920

Elasmobranch bycatch in the Italian Adriatic pelagic trawl fishery.

Directory of Open Access Journals (Sweden)

Sara Bonanomi

Full Text Available Elasmobranchs are among the most threatened long-lived marine species worldwide, and incidental capture is a major source of mortality. The northern central Adriatic Sea, though one of the most overfished basins of the Mediterranean Sea, supports a very valuable marine biodiversity, including elasmobranchs. This study assesses the impact of the northern central Adriatic pelagic trawl fishery on common smooth-hound (Mustelus mustelus, spiny dogfish (Squalus acanthias, common eagle ray (Myliobatis aquila, and pelagic stingray (Pteroplatytrygon violacea by examining incidental catches recorded between 2006 and 2015. The distribution of bycatch events was evaluated using geo-referenced data. Generalized Linear Models were computed to standardize the catch of the four species and to predict the relative abundance of bycatch events. Data analysis shows that most bycatch events involving all four species occurred in the northern Adriatic Sea. The models predicted significant, distinct temporal patterns of standardized catches in line with previous investigations. Water depth, season, and fishing region were the best predictors to explain bycatch events. The present data suggest that the northern Adriatic may be an important nursery area for several elasmobranchs. They also highlight the urgent need for a better understanding of the interactions between elasmobranchs and fisheries to develop and apply suitable, ad hoc management measures.

An algorithm for the detection of the white-tide ('mucilage') phenomenon in the Adriatic Sea using AVHRR data

International Nuclear Information System (INIS)

Tassan, S.

1993-01-01

An algorithm using AVHRR data has been set up for the detection of a white tide consisting of algae secretion ('mucilage'), an event occurring in the Adriatic Sea under particular meteorological conditions. The algorithm, which includes an ad hoc procedure for cloud masking, has been tested with reference to the mucilage map obtained from the analysis of contemporary Thematic Mapper data, as well as by comparing consecutive AVHRR scenes. The main features of the exceptional mucilage phenomenon that took place in the northern basin of the Adriatic Sea in summer 1989 are shown by a time series of maps

Reproductive cycle and sexual maturation of the musky octopus Eledone moschata (Cephalopoda: Octopodidae in the northern and central Adriatic Sea

Directory of Open Access Journals (Sweden)

Svjetlana Krstulović Šifner

2009-09-01

Full Text Available Length-weight relationships, sex ratio, maturity patterns, reproductive outputs, fecundity and spawning period of the musky octopus Eledone moschata (Lamarck, 1798 in the northern and central Adriatic Sea are presented for the first time. Samples were collected on a monthly basis by commercial bottom trawls between October 2001 and June 2003. A total of 1552 specimens were analysed (779 males, 764 females, 9 undetermined. The overall sex ratio was close to 1:1, but during summer males were dominant. Length-weight relationships calculated for each sex and the whole sample showed negative allometric growth (b

Methylmercury in the Gulf of Trieste (Northern Adriatic Sea: From Microbial Sources to Seafood Consumers

Directory of Open Access Journals (Sweden)

Mark E. Hines

2014-01-01

Full Text Available The Gulf of Trieste (northern Adriatic Sea is one of the most mercury-polluted areas in the Mediterranean and in the world due to the past mining activity in the Idrija region (western Slovenia. The link between microbial production of toxic methylmercury (MeHg, and its bioaccumulation and biomagnification in marine food webs of the gulf is at present rather poorly characterized but is critical to understanding the links between sources and higher trophic levels, such as fish, that are ultimately vectors of human and wildlife exposure. This overview explores three major topics: (i the microbial biogeochemical cycling of Hg in the area, (ii the trophic transfer and bioaccumulation of MeHg in pelagic and benthic marine food webs, and (iii human exposure to Hg through marine fish and shellfish consumption. These are important goals since the Gulf of Trieste is an area of great economical importance.

Fish and fishery historical data since the 19th century in the Adriatic Sea, Mediterranean

Science.gov (United States)

Fortibuoni, Tomaso; Libralato, Simone; Arneri, Enrico; Giovanardi, Otello; Solidoro, Cosimo; Raicevich, Saša

2017-09-01

Historic data on biodiversity provide the context for present observations and allow studying long-term changes in marine populations. Here we present multiple datasets on fish and fisheries of the Adriatic Sea covering the last two centuries encompassing from qualitative observations to standardised scientific monitoring. The datasets consist of three groups: (1) early naturalists' descriptions of fish fauna, including information (e.g., presence, perceived abundance, size) on 255 fish species for the period 1818-1936 (2) historical landings from major Northern Adriatic fish markets (Venice, Trieste, Rijeka) for the period 1902-1968, Italian official landings for the Northern and Central Adriatic (1953-2012) and landings from the Lagoon of Venice (1945-2001) (3) trawl-survey data from seven surveys spanning the period 1948-1991 and including Catch per Unit of Effort data (kgh-1 and/or nh-1) for 956 hauls performed at 301 stations. The integration of these datasets has already demonstrated to be useful to analyse historical marine community changes over time, and its availability through open-source data portal will facilitate analyses in the framework of marine historical ecology.

Harmful algae records in Venice lagoon and in Po River Delta (northern Adriatic Sea, Italy).

Science.gov (United States)

Facca, Chiara; Bilaničovà, Dagmar; Pojana, Giulio; Sfriso, Adriano; Marcomini, Antonio

2014-01-01

A detailed review of harmful algal blooms (HAB) in northern Adriatic Sea lagoons (Po River Delta and Venice lagoon) is presented to provide "updated reference conditions" for future research and monitoring activities. In the study areas, the high mollusc production requires the necessity to identify better methods able to prevent risks for human health and socioeconomical interests. So, an integrated approach for the identification and quantification of algal toxins is presented by combining microscopy techniques with Liquid Chromatography coupled with High Resolution Time of Flight Mass Spectrometry (HPLC-HR-TOF-MS). The method efficiency was first tested on some samples from the mentioned coastal areas, where Dinophysis spp. occurred during summer in the sites directly affected by seawaters. Although cell abundance was always <200 cells/L, the presence of Pectenotoxin-2 (PTX2), detected by HPLC-HR-TOF-MS, indicated the potential release of detectable amounts of toxins even at low cell abundance.

Coastal boundary layers in ocean modelling: an application to the Adriatic Sea

International Nuclear Information System (INIS)

Malanotte Rizzoli, P.; Dell'Orto, F.

1981-01-01

Boundary layers play an important role in modelling geophysical fluid-dynamical flows, in as much as they constitute regions of ageostrophic dynamics in which the physical balances characterizing the main interior of the water mass break down. A short synopsis is given of important boundary layers in ocean circulation modelling with specific emphasis drawn upon side wall boundary layers, namely those adjacent to the coastlines of the considered basin. Application of boundary layer analysis is thereafter made for one specific phenomenological situation, namely the Northern Adriatic Sea and the problem posed by its wintertime seasonal circulation. The analysis furnishes a mathematical model fo the coastal strip adjacent to the Italian shoreline, treated as a boundary layer in the density field, starting from general model equations valid throughout the interior of the Northern Adriatic. The boundary layer model is consequently used to modify the side wall boundary condition for the interior density field. Related numerical experiments are shown and compared with previous standard experiments in which the boundary layer contribution to the density field has not been considered. (author)

Dissolved lipid production in the Northern Adriatic (Mediterranean) in response to sea surface warmin

Science.gov (United States)

Gasparovic, Blazenka; Novak, Tihana; Godrijan, Jelena; Mlakar, Marina; MAric, Daniela; Djakovac, Tamara

2017-04-01

Marine dissolved organic matter (OM) represents one of the largest active pools of organic carbon in the global carbon cycle. Oceans and seas are responsible for half of global primary production. Ocean warming caused by climate change is already starting to impact the marine life that necessary will have impact on ocean productivity. The partition of OM production by phytoplankton (major OM producer in seas and ocens) in the conditions of rising temperatures may considerably change. This has implications for the export of organic matter from the photic zone. In this study, we set out to see how annual temperature changes between 10 and 30 C in the Northern Adriatic (Mediterranean) affect production of DOM and particularly dissolved lipids and lipid classes. We have sampled at two stations being oligotrophic and mesotrophic where we expected different system reaction to temperature changes. In addition, we performed microcosm incubations covering temperature range of the NA with nutrient amendments to test whether changes in the available nutrients would reflect those of dissolved OM in the NA. We have selected to work with extracellular OM produced during growth of diatom Chaetoceros curvisetus cultures according to the criteria that genera Chaetoceros are important component of the phytoplankton in the NA and are often among bloom-forming taxa. Details on the dissolved lipid and lipid classes production as plankton responce to rising temperature will be discussed.

Demands for Modern Shipping and SUiveillance of the Adriatic Sea

Directory of Open Access Journals (Sweden)

Martin Lakota

2006-05-01

Full Text Available In this work modem navigation and Adriatic control demandcharacteristics are developed. It correlates the modemnavigation characteristics and the Adriatic sea control. Thepresent operating procedures used for sea control are mentionedas well as the new systems and procedures based on newcomputer and communication technologies (automatic identificationsystems, GPS, computer networks, Internet/Intranetstandards. It discusses unmanned aerial vehicles characteristicsaccording to demands and grading standards for picture/scene interpretation (NIIRS grading scale.

Climate change effects on environment (marine, atmospheric and terrestrial) and human perception in an Italian Region (Marche) and the nearby northern Adriatic Sea.

Science.gov (United States)

Appiotti, F.; Krzelj, M.; Marincioni, F.; Russo, A.

2012-04-01

An integrated analysis of recent climate change, including atmosphere, sea and land, as well as some of the impacts on society, has been conducted on the Marche Region in central Italy and the northern portion of the Adriatic Sea. The Marche Region is one of the 20 administrative divisions of Italy, located at a latitude approximately 43° North, with a total surface area of 9,366 km2 and 1,565,000 residents. The northern Adriatic Sea is the northernmost area of the Mediterranean Sea, and it has peculiar relevance for several aspects (environment, tourism, fisheries, economy). The collected environmental data included meteorological stations (daily maximum and minimum air temperature, daily precipitation), oceanographic stations (sea temperature, salinity, dissolved oxygen, nutrient salts concentration, chlorophyll) and river flows, over the last 50 years. The collected social data include 800 questionnaires and interviews carried out on selected samples of residents, decision-makers and emergency managers. These questionnaires and interviews aimed at highlighting the perception of climate change risks. The trend analysis of air temperature and precipitation data detailed an overall temperature increase in all seasons and rainfall decreases in Winter, Spring and Summer with Autumn increases, influencing river flow changes. Marine data showed a relevant warming of the water column in the period after 1990 in comparison with the previous period, particularly in the cold season. Surface salinity increased in Spring and Summer and strongly decreased in Autumn and Winter (according with the precipitation and river flow changes). These last mentioned changes, combined with anthropogenic effects, also influenced the marine ecosystems, with changes of nutrient salts, chlorophyll and dissolved oxygen. Changes in nutrient discharge from rivers influenced the average marine chlorophyll concentration reduction and the consequent average reduction of warm season hypoxic

Variability of currents in front of the Venice Lagoon, Northern Adriatic Sea

Energy Technology Data Exchange (ETDEWEB)

Cosoli, S.; Gacic, M. [Istituto Nazionale di Oceanografia e di Geofisica Sperimentale - OGS, Sgonico (Trieste) (Italy); Mazzoldi, A. [Consiglio Nazionale delle Ricerche - ISMAR-CNR, Venice (Italy). Ist. di Scienze Marine

2008-07-01

Time scales and modes of variability of the flow in the water column in the Northern Adriatic Sea for late summer 2002 are described based on current record from a single bottom-mounted ADCP in the shallow-water area in front of the Venice Lagoon. The time averaged flow was directed 277 E (CCW), roughly aligned with the coastline, with typical magnitudes in the range 4-6 cm/s and a limited, not significant clockwise veering with depth. Tidal forcing was weak and mainly concentrated in the semidiurnal frequency band, with a barotropic (depth-independent) structure. On a diurnal time scale, tidal signal was biased by the sea-breeze regime and was characterized by a clockwise veering with depth according to the Ekman spiral. A complex EOF analysis on the velocity profile time series extracted two dominant spatial modes of variability, which explained more than 90% of the total variance in the current field. More than 78% of the total variance was accounted for by the first EOF mode, with a barotropic structure that contained the low-frequency components and the barotropic tidal signal at semidiurnal and diurnal frequencies. The second mode had a baroclinic structure with a zero-crossing at mid-depth, which was related with the response of the water column to the high-frequency wind-driven diurnal sea breeze variability. The response of low-passed non-tidal currents to local wind stress was fast and immediate, with negligible temporal lag up to mid-depth. Currents vectors were pointing to the right of wind stress, as expected from the surface Ekman veering, but with angles smaller than the expected ones. A time lag in the range 10 to 11 h was found below 8 m depth, with current vectors pointing to the left of wind stress and a counterclockwise veering towards the bottom. The delay was consistent with the frictional adjustment time scale describing the dynamics of a frictionally dominated flow in shallow water, thus suggesting the importance of bottom friction on the

Verification of an ensemble prediction system for storm surge forecast in the Adriatic Sea

Science.gov (United States)

Mel, Riccardo; Lionello, Piero

2014-12-01

In the Adriatic Sea, storm surges present a significant threat to Venice and to the flat coastal areas of the northern coast of the basin. Sea level forecast is of paramount importance for the management of daily activities and for operating the movable barriers that are presently being built for the protection of the city. In this paper, an EPS (ensemble prediction system) for operational forecasting of storm surge in the northern Adriatic Sea is presented and applied to a 3-month-long period (October-December 2010). The sea level EPS is based on the HYPSE (hydrostatic Padua Sea elevation) model, which is a standard single-layer nonlinear shallow water model, whose forcings (mean sea level pressure and surface wind fields) are provided by the ensemble members of the ECMWF (European Center for Medium-Range Weather Forecasts) EPS. Results are verified against observations at five tide gauges located along the Croatian and Italian coasts of the Adriatic Sea. Forecast uncertainty increases with the predicted value of the storm surge and with the forecast lead time. The EMF (ensemble mean forecast) provided by the EPS has a rms (root mean square) error lower than the DF (deterministic forecast), especially for short (up to 3 days) lead times. Uncertainty for short lead times of the forecast and for small storm surges is mainly caused by uncertainty of the initial condition of the hydrodynamical model. Uncertainty for large lead times and large storm surges is mainly caused by uncertainty in the meteorological forcings. The EPS spread increases with the rms error of the forecast. For large lead times the EPS spread and the forecast error substantially coincide. However, the EPS spread in this study, which does not account for uncertainty in the initial condition, underestimates the error during the early part of the forecast and for small storm surge values. On the contrary, it overestimates the rms error for large surge values. The PF (probability forecast) of the EPS

137Cs in northern Adriatic sediments

International Nuclear Information System (INIS)

Barisic, D.; Lulic, S.; Vdovic, N.; Vertacnik, A.; Juracic, M.

1996-01-01

The activity of 137 Cs in shallow northern Adriatic sediments was obtained on the basis of measurement results from 25 sediment box cores, sampled during the Adriatic Scientific COoperation Program (ASCOP) 16 cruise in the summer 1990. 137 Cs was determined in surface sediments (0-3 cm) and 12-15 cm-deep sediment. It was found that the lowest caesium concentrations correspond to sands, which are spread along the Croatian coast. Parallel to the Italian coast, 137 Cs concentrations in pelites are the highest. It seems that the influence of Po River is significant for 137 Cs activities in recent marine sediments along Italian coast south of Po River delta. Significantly higher 137 Cs activities in 0-3 cm sediment layer can be attributed to the deposition caused by Chernobyl accident. (author)

Coccolithophore diversity and dynamics at a coastal site in the Gulf of Trieste (northern Adriatic Sea)

Science.gov (United States)

Cerino, Federica; Malinverno, Elisa; Fornasaro, Daniela; Kralj, Martina; Cabrini, Marina

2017-09-01

Two years-data (May 2011-February 2013) obtained from a monthly sampling carried out at the coastal long term Ecological Research station C1-LTER in the Gulf of Trieste (northern Adriatic Sea) were analysed to describe the seasonal dynamics and diversity of coccolithophore assemblages and to assess their relationship with environmental forcing. Coccolithophores represented 10.7% of the total Utermöhl phytoplankton that were mainly dominated by small (Emiliania huxleyi, and a secondary peak in May-June (0.7-15.0 · 104 coccospheres L-1), coinciding with the increase of the light intensity and the beginning of the seasonal stratification, dominated by holococcolithophores and small Syracosphaera species. The most abundant taxa were E. huxleyi and holococcolithophores, followed by Acanthoica quattrospina, Syracosphaera species and other minor species. Statistical analyses recognized four distinct groups, corresponding to seasonal variations of environmental conditions. Considering the two years, some species displayed a recurrent seasonal pattern highlighting possible species-specific ecological requirements, while others showed an interannual variability probably due to local factors.

Linear and non-linear sea-level variations in the Adriatic Sea from tide gauge records (1872-2012

Directory of Open Access Journals (Sweden)

Gaia Galassi

2015-03-01

Full Text Available We have analyzed tide gauge data from the Adriatic Sea in order to assess the secular sea-level trend, its acceleration and the existence of possible cyclic variation. Analyzing the sea-level stack of all Adriatic tide gauges, we have obtained a trend of (1.25±0.04 mm yr-1, in agreement with that observed for the last century in the Mediterranean Sea, and an acceleration that is negligibile compared to the average global values. By means of the Ensemble Empirical Mode Decomposition technique, we have evidenced an energetic oscillation with a period of ∼20 years that we relate with the recurrence of opposite phases in the Atlantic Multi–decadal Oscillation and North Atlantic Oscillation indices. We suggest that anomalously high sea-level values observed at all the Adriatic tide gauges during 2010 and 2011 can be explained by the rising phase of this 20 years cycle.

Variability of currents in front of the Venice Lagoon, Northern Adriatic Sea

Directory of Open Access Journals (Sweden)

S. Cosoli

2008-05-01

Full Text Available Time scales and modes of variability of the flow in the water column in the Northern Adriatic Sea for late summer 2002 are described based on current record from a single bottom-mounted ADCP in the shallow-water area in front of the Venice Lagoon.

The time averaged flow was directed 277° E (CCW, roughly aligned with the coastline, with typical magnitudes in the range 4–6 cm/s and a limited, not significant clockwise veering with depth. Tidal forcing was weak and mainly concentrated in the semidiurnal frequency band, with a barotropic (depth-independent structure. On a diurnal time scale, tidal signal was biased by the sea-breeze regime and was characterized by a clockwise veering with depth according to the Ekman spiral.

A complex EOF analysis on the velocity profile time series extracted two dominant spatial modes of variability, which explained more than 90% of the total variance in the current field. More than 78% of the total variance was accounted for by the first EOF mode, with a barotropic structure that contained the low-frequency components and the barotropic tidal signal at semidiurnal and diurnal frequencies. The second mode had a baroclinic structure with a zero-crossing at mid-depth, which was related with the response of the water column to the high-frequency wind-driven diurnal sea breeze variability.

The response of low-passed non-tidal currents to local wind stress was fast and immediate, with negligible temporal lag up to mid-depth. Currents vectors were pointing to the right of wind stress, as expected from the surface Ekman veering, but with angles smaller than the expected ones. A time lag in the range 10 to 11 h was found below 8 m depth, with current vectors pointing to the left of wind stress and a counterclockwise veering towards the bottom. The delay was consistent with the frictional adjustment time scale describing the dynamics of a frictionally dominated flow in shallow water, thus

Variability of currents in front of the Venice Lagoon, Northern Adriatic Sea

Directory of Open Access Journals (Sweden)

S. Cosoli

2008-05-01

Full Text Available Time scales and modes of variability of the flow in the water column in the Northern Adriatic Sea for late summer 2002 are described based on current record from a single bottom-mounted ADCP in the shallow-water area in front of the Venice Lagoon. The time averaged flow was directed 277° E (CCW, roughly aligned with the coastline, with typical magnitudes in the range 4–6 cm/s and a limited, not significant clockwise veering with depth. Tidal forcing was weak and mainly concentrated in the semidiurnal frequency band, with a barotropic (depth-independent structure. On a diurnal time scale, tidal signal was biased by the sea-breeze regime and was characterized by a clockwise veering with depth according to the Ekman spiral. A complex EOF analysis on the velocity profile time series extracted two dominant spatial modes of variability, which explained more than 90% of the total variance in the current field. More than 78% of the total variance was accounted for by the first EOF mode, with a barotropic structure that contained the low-frequency components and the barotropic tidal signal at semidiurnal and diurnal frequencies. The second mode had a baroclinic structure with a zero-crossing at mid-depth, which was related with the response of the water column to the high-frequency wind-driven diurnal sea breeze variability. The response of low-passed non-tidal currents to local wind stress was fast and immediate, with negligible temporal lag up to mid-depth. Currents vectors were pointing to the right of wind stress, as expected from the surface Ekman veering, but with angles smaller than the expected ones. A time lag in the range 10 to 11 h was found below 8 m depth, with current vectors pointing to the left of wind stress and a counterclockwise veering towards the bottom. The delay was consistent with the frictional adjustment time scale describing the dynamics of a frictionally dominated flow in shallow water, thus suggesting the importance of

Sea level variability at Adriatic coast and its relationship to atmospheric forcing

Energy Technology Data Exchange (ETDEWEB)

Bergant, K. [Centre for Atmospheric Research, Nova Gorica Polytechnic, Nova Gorica (Slovenia); Susnik, M.; Strojan, I. [Dept. of Hydrology, Environmental Agency of the Republic of Slovenia, Ljubljana (Slovenia); Shaw, A.G.P. [James Rennel Div., National Oceanography Centre, Empress Dock, Southampton (United Kingdom)

2005-07-01

Sea level (SLH) variability at the Adriatic coast was investigated for the period 1872-2001 using monthly average values of observations at 13 tide gauge stations. Linear trends and seasonal cycles were investigated first and removed afterwards from the data. Empirical orthogonal functions (EOF) analysis was used further on remaining anomalies (SLA) to extract the regional intermonthly variability of SLH. It was found that the leading EOF and its principal component (PC) explain a major part of SLA variability (92%). The correlation between the reconstructed SLA, based on leading EOF and its PC, and overlapping observed SLA values for selected tide gauge stations is between 0.93 and 0.99. Actual SLH values at tide gauge stations can be reconstructed and some gaps in the data can be filled in on the basis of estimated SLA values if reasonable estimates of long-term trends and seasonal cycles are also available. A strong, seasonally dependent relationship between SLA at the Adriatic coast and atmospheric forcing, represented by sea level pressure (SLP) fields, was also found. Comparing the time series of leading PC and gridded SLP data for the period 1948-2001, the highest correlation coefficients (r) of -0.92 in winter, -0.84 in spring, -0.66 in summer, and -0.91 in autumn were estimated for a SLP grid point located in northern Italy. The SLP variability on this grid point contains information about the isostatic response of the sea level at the Adriatic coast, but can also be treated as a sort of teleconnection index representing the large-scale SLP variability across central and southern Europe. To some extent the large-scale SLP variability that affects the SLA at the Adriatic coast can be related to the North Atlantic Oscillation (NAO), because significant correlations were found between the NAO index and the first PC of SLA (r{sub winter}=-0.56, r{sub spring}=-0.45, r{sub summer}=-0.48, and r{sub autumn}=-0.43) for the period 1872-2001. The use of partial least

First records of two planktonic Indo-Pacific diatoms: Chaetoceros bacteriastroides and C. pseudosymmetricus in the Adriatic Sea

Directory of Open Access Journals (Sweden)

Marijeta Čalić

2018-01-01

Full Text Available Unusual occurrence of planktonic diatom species, Chaetoceros bacteriastroides and Chaetoceros pseudosymmetricus, was noticed in three different marine ecosystems of Adriatic Sea: the Krka Estuary and Telaščica Bay in the Central Adriatic, and in southern Adriatic offshore. From 2010 to 2015, these two Chaetoceros species were recorded in heterogeneous environmental conditions and in a very low abundances. Both species are regarded as very rare in world oceans, and consequently knowledge of their distribution and ecology is rather poor. Primarily described from tropical waters and showing Indo-Pacific distribution, C. bacteriastroides and C. pseudosymmetricus findings in Adriatic represent the northernmost records in world's oceans and seas. For C. pseudosymmetricus this is also the first occurrence in European seas. Areal expansion and introduction of new phytoplankton species in the Adriatic Sea might be related to different circulation regimes in the Ionian Sea and the concurrent rise in sea temperature in the Mediterranean in the last decade. Recent investigations have shown that entering currents, of either Atlantic/Western Mediterranean or Eastern Mediterranean origin, modify the composition of the plankton community in the Adriatic by bringing different newcomers.

Operability Guidelines For Product Tanker In Heavy Weather In The Adriatic Sea

Directory of Open Access Journals (Sweden)

Mudronja Luka

2014-06-01

Full Text Available This paper presents operability guidelines for seafarers on a product tanker which navigates in the Adriatic Sea during heavy weather. Tanker route starts from the Otranto strait in the south to the island Krk in the north of Adriatic Sea. Heavy weather is caused by south wind called jugo (blowing from E-SE to SS-E, sirocco family. Operability guidelines are given based on an operability criteria platform for presenting ship seakeeping characteristics. Operability criteria considered in this paper are propeller emergence, deck wetness and bow acceleration of a product tanker. Limiting values of mentioned criteria determine sustainable speed. Heavy weather is described by extreme sea state of 7.5 m wave height. Wave spectrum used in this paper is Tabain spectrum which is developed specifically for Adriatic Sea. Seafarer's approach of decisions making in extreme weather is also shown and servers as a guideline for further research of the authors.

Copper complexing ligands and organic matter characterization in the northern Adriatic Sea

Science.gov (United States)

Plavšić, Marta; Gašparović, Blaženka; Strmečki, Slađana; Vojvodić, Vjeročka; Tepić, Nataša

2009-11-01

The study on dissolved organic ligands capable to complex copper ions (L T), surface-active substances (SAS) and dissolved organic carbon (DOC) in the Northern Adriatic Sea station (ST 101) under the influence of Po River was conducted in period from 2006-2008. The acidity of surface-active organic material (Ac r) was followed as well. The results are compared to temperature and salinity distributions. On that way, the contribution of the different pools of ligands capable to complex Cu ions could be determined as well as the influence of aging and transformation of the organic matter. The L T values in the investigated period were in the range of 40-300 nmol l -1. The range of DOC values for surface and bottom samples were 0.84-1.87 mg l -1 and 0.80-1.30 mg l -1, respectively. Total SAS concentrations in the bottom layer were 0.045-0.098 mg l -1 in equiv. of Triton-X-100 while those in the surface layer were 0.050-0.143 mg l -1 in equiv. of Triton-X-100. The majority of organic ligands responsible for Cu binding in surface water originate from new phytoplankton production promoted by river borne nutrients. Older, transformed organic matter, possessing higher relative acidity, is the main contributor to the pool of organic ligands that bind copper in the bottom samples. It was estimated that ˜9% of DOC in surface samples and ˜12% of DOC in the bottom samples are present as ligands capable to complex copper ions.

Adriatic storm surges and related cross-basin sea-level slope

Science.gov (United States)

Međugorac, Iva; Orlić, Mirko; Janeković, Ivica; Pasarić, Zoran; Pasarić, Miroslava

2018-05-01

Storm surges pose a severe threat to the northernmost cities of the Adriatic coast, with Venice being most prone to flooding. It has been noted that some flooding episodes cause significantly different effects along the eastern and western Adriatic coasts, with indications that the difference is related to cross-basin sea-level slope. The present study aims to determine specific atmospheric conditions under which the slope develops and to explore connection with increased sea level along the two coastlines. The analysis is based on sea-level time series recorded at Venice and Bakar over the 1984-2014 interval, from which 38 most intensive storm-surge episodes were selected, and their meteorological backgrounds (ERA-Interim) were studied. The obtained sea-level extremes were grouped into three categories according to their cross-basin sea-level slope: storm surges that slope strongly westward (W type), those that slope eastward (E type) and ordinary storm surges (O type). Results show that the slope is controlled by wind action only, specifically, by the wind component towards a particular coast and by the cross-basin shear of along-basin wind. Meteorological fields were used to force an oceanographic numerical model in order to confirm the empirically established connection between the atmospheric forcing and the slope. Finally, it has been found that the intensity of storm surges along a particular Adriatic coast is determined by an interplay of sea-level slopes in the along and cross-basin directions.

Trends of anchovy (Engraulis encrasilocus, L. biomass in the northern and central Adriatic Sea

Directory of Open Access Journals (Sweden)

Alberto Santojanni

2003-09-01

Full Text Available Anchovy (Engraulis encrasicolus, L. is one of the most important commercial species of the northern and central Adriatic Sea. The mean annual catch of anchovy estimated by IRPEM for these areas, in the time interval 1975-1996, is equal to 25,000 tonnes. Estimates of anchovy stock biomass at sea in the time interval 1975-1996 were obtained using two population dynamics methods based on different data inputs: Virtual Population Analysis (VPA and the DeLury model with recruitment index. VPA was carried out tuning the estimated fishing mortality rate at age by fitting on corresponding Catch Per Unit of fishing Effort (CPUE. Both VPA and the DeLury model yielded sensible results. The effect on the assessments due to the use of a different birth date and thus of split-year data was investigated. Biomass values as well as patterns over time so estimated were similar on the basis of both assessment methods and calendar year versus split-year data. In particular, the biomass in more recent years (around 100,000 tonnes was lower than in the second half of the 1970s and first half of the 1980s (over 200,000 tonnes. The minimum value (lower than 50,000 tonnes was always estimated in 1987, when a strong drop in the catch and crisis of the anchovy fishery took place. Though high values of both fishing effort and fishing mortality/exploitation rate were obtained for some years before 1987, very low levels of recruitment in 1986 and 1987 seem to be mainly responsible for the collapse of the stock.

Tectonic Interpretation of CHAMP Geopotential Data over the Northern Adriatic Sea.

Science.gov (United States)

Taylor, P. T.; Kim, H. R.; Mayer-Gürr, T.

2006-05-01

Recent aeromagnetic anomaly compilations (Chiappini et al., 2000 and Tontini et al., 2004) show a large positive (>700 nT) northwest-southeast trending magnetic anomaly off the Dalmatian coast. Unfortunately these aeromagnetic data cover only a part of this anomaly. We wanted to investigate if this large magnetic anomaly could be detected at satellite altitude and what is the extent and source of this feature. Therefore, magnetic and gravity anomaly maps were made from the CHAMP geopotential data, measured at the current low altitude of 345-350 km over the northern Adriatic Sea. We made the magnetic anomaly map over this relatively small region using 36 descending and 85 ascending orbits screened to be at the lowest altitude and the most magnetically quietest data. We removed the main field component (i.e., IGRF-10 up to degree and order 13) and then demeaned individual tracks and subtracted a second order polynomial to remove regional and/or un-modeled external field features. The resulting map from these well-correlated anomalies revealed a positive magnetic anomaly (>2 nT). Reduction-to-the pole brought these CHAMP anomaly features into coincidence with the aeromagnetic data. Previously Cantini et al. (1999) compared the surface magnetic data with MAGSAT by continuing upward the former and downwards the latter to 100 km and found a good correlation for wavelengths of 300-500 km. We also investigated the CHAMP gravity data. They were reduced using the kinematic short-arc integration method (Ilk et al., 2005 and Mayer Gürr et al., 2005). However, no corresponding short-wavelength gravity anomaly was observed in our study area. This tectonically complex region is under horizontal stress and the source of the large magnetic anomaly can be modelled by an associated ophiolite melange.

{sup 137}Cs in northern Adriatic sediments

Energy Technology Data Exchange (ETDEWEB)

Barisic, D; Lulic, S; Vdovic, N; Vertacnik, A [Center for Marine Research - Department Zagreb, ' Ruder Boskovic' Institute, Zagreb (Croatia); Juracic, M [Department of Geology, Faculty of Natural Sciences, University of Zagreb, Zagreb (Croatia)

1996-01-01

The activity of {sup 137}Cs in shallow northern Adriatic sediments was obtained on the basis of measurement results from 25 sediment box cores, sampled during the Adriatic Scientific COoperation Program (ASCOP) 16 cruise in the summer 1990. {sup 137}Cs was determined in surface sediments (0-3 cm) and 12-15 cm-deep sediment. It was found that the lowest caesium concentrations correspond to sands, which are spread along the Croatian coast. Parallel to the Italian coast, {sup 137}Cs concentrations in pelites are the highest. It seems that the influence of Po River is significant for {sup 137}Cs activities in recent marine sediments along Italian coast south of Po River delta. Significantly higher {sup 137}Cs activities in 0-3 cm sediment layer can be attributed to the deposition caused by Chernobyl accident. (author)

On the Isotopic Altitude Effect of Precipitation in the Northern Adriatic (Croatia)

Energy Technology Data Exchange (ETDEWEB)

Roller-Lutz, Z.; Mance, D.; Hunjak, T., E-mail: Roller@medri.hr [Stable Isotope Laboratory, Medical Faculty, University of Rijeka, Rijeka (Croatia); Lutz, H. O. [Stable Isotope Laboratory, Medical Faculty, University of Rijeka, Rijeka (Croatia); Physics Faculty, Bielefeld University, Bielefeld (Germany)

2013-07-15

The upper (northern) Adriatic is very rich in precipitation. This input into the water system and its stable isotope composition is a basic factor, knowledge of which is required for proper use and management of water resources. The geomorphology of the region (e.g., mountains of 1400 m next to the sea) can cause specific local conditions. The isotopic composition of precipitation has been measured in various locations at different altitudes. For {delta}{sup 18}O this 'altitude effect' is found to lie around -0.2 per mille /100 m; its exact value depends on the specific location and the season. The {delta}{sup 2}H values and the d-excess vary correspondingly. (author)

Intense air-sea exchanges and heavy orographic precipitation over Italy: The role of Adriatic sea surface temperature uncertainty

Science.gov (United States)

Stocchi, Paolo; Davolio, Silvio

2017-11-01

Strong and persistent low-level winds blowing over the Adriatic basin are often associated with intense precipitation events over Italy. Typically, in case of moist southeasterly wind (Sirocco), rainfall affects northeastern Italy and the Alpine chain, while with cold northeasterly currents (Bora) precipitations are localized along the eastern slopes of the Apennines and central Italy coastal areas. These events are favoured by intense air-sea interactions and it is reasonable to hypothesize that the Adriatic sea surface temperature (SST) can affect the amount and location of precipitation. High-resolution simulations of different Bora and Sirocco events leading to severe precipitation are performed using a convection-permitting model (MOLOCH). Sensitivity experiments varying the SST initialization field are performed with the aim of evaluating the impact of SST uncertainty on precipitation forecasts, which is a relevant topic for operational weather predictions, especially at local scales. Moreover, diagnostic tools to compute water vapour fluxes across the Italian coast and atmospheric water budget over the Adriatic Sea have been developed and applied in order to characterize the air mass that feeds the precipitating systems. Finally, the investigation of the processes through which the SST influences location and intensity of heavy precipitation allows to gain a better understanding on mechanisms conducive to severe weather in the Mediterranean area and in the Adriatic basin in particular. Results show that the effect of the Adriatic SST (uncertainty) on precipitation is complex and can vary considerably among different events. For both Bora and Sirocco events, SST does not influence markedly the atmospheric water budget or the degree of moistening of air that flows over the Adriatic Sea. SST mainly affects the stability of the atmospheric boundary layer, thus influencing the flow dynamics and the orographic flow regime, and in turn, the precipitation pattern.

Selenium and Mercury Interactions in Apex Predators from the Gulf of Trieste (Northern Adriatic Sea

Directory of Open Access Journals (Sweden)

Jadran Faganeli

2018-02-01

Full Text Available Since the environmental levels of selenium (Se can moderate the bioaccumulation and toxicity of mercury (Hg in marine organisms, their interactions were studied in seawater, sediments, plankton and the benthic (Bull ray Pteromylaeus bovinus, Eagle ray Myliobatis aquila and the pelagic (Pelagic stingray Dasyiatis violacea rays, as apex predators in the Gulf of Trieste (Northern Adriatic Sea. Male and female rays showed no difference in the Se contents in muscle tissue. Pelagic species contained higher Se levels in muscle but slightly lower levels in the livers of both genders. The Hg/Se ratios in seawater dissolved and colloidal fractions, plankton and sediment were <0.5, while those in particulate matter were <1.3. In benthic ray species, a parallel increase in Se and Hg in muscle was observed, so that an increased in Hg (MeHg bioaccumulation results in Se coaccumulation. The Hg/Se ratios (molar in muscle and liver of pelagic and benthic rays were <1.4 and <0.7, respectively. The low levels of Hg in muscle and liver in all the ray species corresponded to low Hg/Se ratios and increases in muscle and liver to 1 at 7 µg/g, dry weight (dw and 5 µg/g dw, respectively, i.e., about 1.6 µg/g wet weight (ww.

The Henetus wave forecast system in the Adriatic Sea

Directory of Open Access Journals (Sweden)

L. Bertotti

2011-11-01

Full Text Available We describe the Henetus wave forecast system in the Adriatic Sea. Operational since 1996, the system is continuously upgraded, especially through the correction of the input ECMWF wind fields. As these fields are of progressively improved quality with the increasing resolution of the meteorological model, the correction needs to be correspondingly updated. This ensures a practically constant quality of the Henetus results in the Adriatic Sea since 1996. After suitable and extended validation of the quality of the results at different forecast ranges, the operational range has been recently extended to five days. The Henetus results are used also to improve the tidal forecast on the Venetian coasts and the Venice lagoon, particularly during the most severe events. Extensive statistics on the model performance are provided, both as analysis and forecast, by comparing the model results versus both satellite and buoy data.

NUTRITIVE VALUE OF TROUT (ONCORHYNCHUS MYKISS FARMED IN ADRIATIC SEA

Directory of Open Access Journals (Sweden)

Tibor Janči

2013-01-01

Full Text Available The aim of this study was to determine the chemical composition of fresh and cold smoked rainbow trout fillets (Oncorhynchus mykiss farmed in the Adriatic sea by measuring water, fat, protein, salt and ash content, fatty acid profile with an emphasis on eicosapentaenoic (EPA and docosahexaenoic (DHA fatty acids. Physical characteristics were determined by pH and color measurements. Analysis was performed on homogenized fish muscles without skin and bones. Determination of moisture, ash, fat and protein was conducted according to AOAC (1995. Determination of fatty acid content of previously prepared methyl esters (HRN EN ISO 5509, 2004 was conducted by gas chromatography according to HRN EN ISO 5508 (1999. Results showed that fresh rainbow trout farmed in the Adriatic sea is an excellent protein source (21.21% but has slightly lower fat (5.21% and omega-3 fatty acid content (12.52 % compared to the results of other studies. Fat and omega-3 fatty acid content was not decreased by the process of cold smoking. Overall, fresh and smoked trout farmed in the Adriatic may be regarded as food high in nutritional value.

Environmental state of the Slovenian part of the Adriatic Sea

Directory of Open Access Journals (Sweden)

Valentina Brečko Grubar

2010-06-01

Full Text Available Slovenian part of the Adriatic Sea is its most northern part which occupies approximately 200 km2 and is a part of the wider Gulf of Trieste. Slovenian coast consists of 47 kilometers of mostly steep, abrasive marl and sandstone coast. Low accumulation coast is located only at the mouths of the watercourses and represents but a smaller portion, whereas the smallest part is occupied by the limestone abrasion coast. Mainland coastal region is mostly hillside and has a very diverse relief, while plains, in smaller numbers, are located only in the lower parts of the river valleys. Slovenian sea indents the mainland by two larger gulfs: the Gulf of Koper and of Piran and is predominately very shallow. The average depth is around 18 m and the largest depth is 38 m at the Madona cape near Piran. Sea bottom is mostly covered by the thick layer of sediments deposited after the abrasion of the steep cliff coast and by the accumulation of the river alluvium. Due to its shallowness the sea is exposed to high temperature fluctuations and due to the fresh water influx also to the changes of its salinity. The circulation of the sea water is mainly induced by the tide and wind activities, mostly the Bora (strong north-easterly wind which significantly influences the vertical circulation of the water. Water current is weak and unstable. There is a large influx of nutrients into the Slovenian sea, resulting from the soil erosion, surface water influx, watercourses and direct emissions of waste waters into the sea. The consequence of the mentioned sea characteristics is a great landscape sensitivity of the coastal sea ecosystem. During summer the sea warms intensely and when accompanied by the weak water circulation, we are often witnessing the lack of oxygen in the deeper layers of the water, intensive algae growth and sea blooming, which points to exceeded self-cleaning (assimilation capacities of the marine ecosystem. The major polluters are the coastal towns

Environmental state of the Slovenian part of the Adriatic Sea

Directory of Open Access Journals (Sweden)

Valentina Brečko Grubar

2010-01-01

Full Text Available Slovenian part of the Adriatic Sea is its most northern part which occupies approximately 200 km2 and is a part of the wider Gulf of Trieste. Slovenian coast consists of 47 kilometers of mostly steep, abrasive marl and sandstone coast. Low accumulation coast is located only at the mouths of the watercourses and represents but a smaller portion, whereas the smallest part is occupied by the limestone abrasion coast. Mainland coastal region is mostly hillside and has a very diverse relief, while plains, in smaller numbers, are located only in the lower parts of the river valleys. Slovenian sea indents the mainland by two larger gulfs: the Gulf of Koper and of Piran and is predominately very shallow. The average depth is around 18 m and the largest depth is 38 m at the Madona cape near Piran. Sea bottom is mostly covered by the thick layer of sediments deposited after the abrasion of the steep cliff coast and by the accumulation of the river alluvium. Due to its shallowness the sea is exposed to high temperature fluctuations and due to the fresh water influx also to the changes of its salinity. The circulation of the sea water is mainly induced by the tide and wind activities, mostly the Bora (strong north-easterly wind which significantly influences the vertical circulation of the water. Water current is weak and unstable. There is a large influx of nutrients into the Slovenian sea, resulting from the soil erosion, surface water influx, watercourses and direct emissions of waste waters into the sea. The consequence of the mentioned sea characteristics is a great landscape sensitivity of the coastal sea ecosystem. During summer the sea warms intensely and when accompanied by the weak water circulation, we are often witnessing the lack of oxygen in the deeper layers of the water, intensive algae growth and sea blooming, which points to exceeded self-cleaning (assimilation capacities of the marine ecosystem. The major polluters are the coastal towns

Numerical modelling of an oil spill in the northern Adriatic

Directory of Open Access Journals (Sweden)

Marin Paladin

2012-04-01

Full Text Available Hypothetical cases of oil spills, caused by ship failure in the northern Adriatic, are analysed with the aim of producing three-dimensional models of sea circulation and oil contaminant transport. Sea surface elevations, sea temperature and salinity fields are applied as a forcing argument on the model's open boundaries.The Aladin-HR model with a spatial resolution of 8 km and a time interval of 3 hours is used for atmospheric forcing. River discharges along the coastline in question are introduced as point source terms and are assumed to have zero salinity at their respective locations. The results of the numerical modelling of physical oceanography parameters are validated by measurements carried out in the ‘Adriatic Sea monitoring programme’ in a series of current meter and CTD stations in the period from 1 January 2008 to 15 November 2008.The oil spill model uses the current field obtained from a circulation model.Besides the convective dispersive transport of oil pollution (Lagrangian model of discrete particles, the model takes into account a number of reactive processes such as emulsification, dissolution, evaporation and heat balance between the oil,sea and atmosphere. An actual event took place on 6 February 2008,when the ship `Und Adriyatik' caught fire in the vicinity of the town of Rovinj (Croatia en route from Istanbul (Turkey to Trieste (Italy. At the time the fire broke out, the ship was carrying around 800 tons of oil. Thanks to the rapid intervention of the firedepartment, the fire was extinguished during the following 12 hours,preventing possible catastrophic environmental consequences. Based on this occurrence, five hypothetical scenarios of ship failure with a consequent spill of 800 tons of oil over 12 hours were analysed. The main distinction between the simulated scenarios is the time of the start of the oil spill, corresponding to the times when stronger winds were blowing (>7 m s-1 with a minimum duration of 24 h

Wastewater Pollution from Cruise Ships in the Adriatic Sea

Directory of Open Access Journals (Sweden)

Tina Perić

2016-08-01

Full Text Available The global growth of cruise tourism has brought increasing concern for the pollution of the marine environment. Marine pollution from sanitary wastewater is a problem especially pronounced on large cruise ships where the number of people on board may exceed 8,000. To evaluate future marine pollution in any selected period of time it is necessary to know the movement of ships in the Adriatic Sea. This paper presents the problem of marine pollution by sanitary wastewater from cruise ships, wastewater treatment technology and a model of cruise ship traffic in the Adriatic Sea considering MARPOL Annex IV areas of limited wastewater discharge. Using the model, it is possible to know in advance the routes of the cruisers and retention time in certain geographic areas. The data obtained by this model can be used as input parameters for evaluation model of wastewater pollution or for evaluation of other types of pollution from cruise ships.

Severe flooding along the eastern Adriatic coast: the case of 1 December 2008

Science.gov (United States)

Međugorac, Iva; Pasarić, Miroslava; Orlić, Mirko

2015-06-01

This paper addresses an extraordinary storm surge in the Northern Adriatic that was more pronounced on the eastern than on the western shore. On 1 December 2008, Adriatic monitoring stations detected exceptionally high sea levels; the oldest Croatian tide gauge station recorded the highest water level in its operating history at the time. Apart from the Northern Adriatic, large portion of the Dalmatian Coast was also exposed to high water levels, while Venice experienced a less-dramatic event. This marine storm was different from the capital storm of 4 November 1966 during which the surge had the highest impact ahead of Venice and along the north-western coastline. The 2008 event is studied here in detail, and the mechanisms that resulted in the different flooding of the two shores are identified. The study is based on hourly sea level, air pressure and wind data measured along both basin sides together with ECMWF reanalysis fields. Four components of sea-level evolution are identified: the storm surge, tide, Adriatic seiche and, low-frequency variability. The 2008 event was the outcome of a fine interplay between the first three components, which were all superimposed on the raised sea level due to low-frequency variability. The marine storm differed from the 1966 storm in the atmospheric forcing and relative timing of all contributing processes. The 2008 flooding of the eastern coast was mainly due to the Sirocco-wind shear, whereas the 1966 flooding of the western coast was due to the combined effect of almost uniform Sirocco and bottom slope.

Modeling the drift of plastics in the Adriatic Basin

Science.gov (United States)

Liubartseva, Svitlana; Coppini, Giovanni; Lecci, Rita; Creti, Sergio

2016-04-01

Recently, plastic pollution at sea has become widely recognized as an acute environmental problem. Distribution of plastics in the marine environment is controlled by (1) locations and time-varying intensity of inputs; (2) the dynamics of the upper mixed layer of the ocean, where the majority of plastics float; and (3) the sinks of plastics. In the present work, we calculate the plastic concentrations at the sea surface and fluxes onto the coastline (2009-2015) that originated from terrestrial and maritime inputs. We construct a Markov chain model based on coupling the MEDSLIK-II model (De Dominicis et al., 2013) with the daily Adriatic Forecasting System (AFS) ocean currents simulations (1/45° horizontal resolution) (Guarneri et al., 2010) and ECMWF surface wind analyses (0.25° horizontal and 6-h temporal resolutions). We assume that the coastline is the main sink of plastics in the Adriatic Sea (Liubartseva et al., 2015). Our calculations have shown that the mean particle half-life in the basin approximately equals 43.7 days, which allows us to define the Adriatic Sea as a highly dissipative system with respect to floating plastics. On long-term time-mean scales, the most polluted sea surface area (more than 10 g/km2 floating plastics) is represented by an elongated band shifted to the Italian coastline and narrowed from northwest to southeast. That corresponds to the spatial distributions of plastic inputs, and indicates a tight connection with patterns of the general Adriatic circulation, including the Western Adriatic Coastal Current and the South Adriatic gyre. On seasonal time-mean scales, we indicate the winter plastics' expansion into the basin's interior, spring trapping in the northern Adriatic, summer cleansing the middle and southern Adriatic and autumn spreading into the southeastern Adriatic. Distinctive coastal "hot spot" is found on the Po Delta coastline that receives a plastic flux of 70 kg/(kmṡday). Complex source-receptor relationships

COMPETITION BETWEEN CONTAINER PORTS IN THE NORTHERN ADRIATIC

OpenAIRE

Elen Twrdy; Milan Batista

2014-01-01

World trade has changed in the last decade such that container traffic flows are oriented towards more parts of the European continent. The European container port system is not a homogeneous set of ports; instead it consists of several big ports (e.g., Rotterdam, Hamburg, Algeciras...) and a large number of medium and small ports. Northern Adriatic (NA) ports, namely Rijeka, Koper, Trieste, Venice and Ravenna, are small ports. Each of these ports have different development plans but in varyi...

Benthic foraminifera from the Adriatic Sea : principles of phenotypic variation

NARCIS (Netherlands)

Jorissen, F.J.

1988-01-01

The distribution and morphology of the benthic foraminifera in the Adriatic Sea appear to be strongly dependent on two primary controlling environmental parameters, oxygen concentration and food availability. These factors are both governed by the runoff from the Po and other Italian rivers, and

Comparison of SeaWiFS and MODIS time series of inherent optical properties for the Adriatic Sea

Directory of Open Access Journals (Sweden)

F. Mélin

2011-05-01

Full Text Available Time series of inherent optical properties (IOPs derived from SeaWiFS and MODIS are compared for the Adriatic Sea. The IOPs are outputs of the Quasi-Analytical Algorithm and include total absorption a, phytoplankton absorption a_ph, absorption associated with colored detrital material (CDM a_cdm, and particle backscattering coefficient b_bp. The average root-mean square difference Δ computed for log-transformed distributions decreases for $a$ from 0.084 at 412 nm to 0.052 at 490 nm, is higher for a_ph(443 (0.149 than for a_cdm(443 (0.071, and is approximately 0.165 for b_bp at various wavelengths. The SeaWiFS a at 443 and 490 nm, a_ph at 443 nm and b_bp are on average higher than the MODIS counterparts. Statistics show significant variations in space and time. There is an overall increasing gradient for Δ associated with the absorption terms from the open southern and central Adriatic to the northwest part of the basin, and a reversed gradient for the particulate backscattering coefficient. For time series analysis, only a(412 and a_cdm(443 currently present an unbiased continuity bridging the SeaWiFS and MODIS periods for the Adriatic Sea.

Distribution of aerobic anoxygenic phototrophs in the Eastern Adriatic Sea

Czech Academy of Sciences Publication Activity Database

Šantić, D.; Šestanović, S.; Vrdoljak, A.; Šolić, M.; Kušpilić, G.; Ninčević Gladan, Ž.; Koblížek, Michal

2017-01-01

Roč. 130, SEP 2017 (2017), s. 134-141 ISSN 0141-1136 R&D Projects: GA MŠk(CZ) LO1416 Institutional support: RVO:61388971 Keywords : Aerobic anoxygenic phototrophs * Adriatic sea * Picoplankton Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 3.101, year: 2016

Comparison of hydrothermal activity between the Adriatic and the Red Sea rift margins

Science.gov (United States)

Ball, Philip; Incerpi, Nicolò; Birkle, Peter; Lacsamana, Elizabeth; Manatschal, Gianreto; Agar, Susan; Zhang, Shuo; Borsato, Ron

2017-04-01

Detailed field studies, and access to high-quality seismic reflection and refraction data have led to an improved understanding of the architecture and evolution of magma poor and magma rich margins. Associated with the spatial-temporal evolution of the rift, it is evident that there are evolving, extensive, fluid-rock interactions due to the infiltration of fluids within the sediment, basement and lithospheric mantle. Key questions therefore arise: What are the different fluid-rock reactions that can be typed to different geodynamic stages of the rift evolution? What are their compositions and how do they interact with their environment (basement, sediments, evaporites, hydrosphere, and magmatism)? What are the implications for the evolution of the margin rheology, thermal structure, depositional environments/organic matter maturity, and reservoir quality? The Adriatic paleo-rifted margin is preserved in both SE Switzerland and northern Italy. The field exposures provide a unique opportunity to study the fluid flow history of a hyperextended magma poor extensional margin. Analysis of breccias, cement veins and replacement minerals reveal that the margin records a complex, long-lasting history of dolomitization, calcification and silicification during the Jurassic rifting. The Red Sea by contrast is a young rifted margin. It differs from the paleo-Adriatic margin by several characteristics: volcanism is more evident, and syn-tectonic sediments, including evaporites (halite and anhydrite) are thicker. Several core and fluid samples are available from both onshore and offshore wells, which reveal rift-related hydrothermal alteration. In addition, we find evidence for the presence of an extreme dynamic hydraulic system with infiltration of surface water into sub-salt units during Late Pleistocene. In this study we present results from petrographic and geochemical analysis of basement and sedimentary rocks from Adriatic field-derived samples and core/subsurface fluid

Spatial and temporal variability of thermohaline properties in the Bay of Koper (northern Adriatic Sea)

Science.gov (United States)

Soczka Mandac, Rok; Žagar, Dušan; Faganeli, Jadran

2013-04-01

In this study influence of fresh water discharge on the spatial and temporal variability of thermohaline (TH) conditions is explored for the Bay of Koper (Bay). The Bay is subject to different driving agents: wind stress (bora, sirocco), tidal and seiches effect, buoyancy fluxes, general circulation of the Adriatic Sea and discharge of the Rizana and Badaševica rivers. These rivers have torrential characteristics that are hard to forecast in relation to meteorological events (precipitation). Therefore, during episodic events the spatial and temporal variability of TH properties in the Bay is difficult to determine [1]. Measurements of temperature, salinity and turbidity were conducted monthly on 35 sampling points in the period: June 2011 - December 2012. The data were processed and spatial interpolated with an objective analysis method. Furthermore, empirical orthogonal function analysis (EOF) [2] was applied to investigate spatial and temporal TH variations. Strong horizontal and vertical stratification was observed in the beginning of June 2011 due to high fresh water discharge of the Rizana (31 m3/s) and Badaševica (2 m3/s) rivers. The horizontal gradient (ΔT = 6°C) was noticed near the mouth of the Rizana river. Similar pattern was identified for salinity field on the boundary of the front where the gradient was ΔS = 20 PSU. Vertical temperature gradient was ΔT = 4°C while salinity gradient was ΔS = 18 PSU in the subsurface layer at depth of 3 m. Spatial analysis of the first principal component (86% of the total variance) shows uniform temperature distribution in the surface layer (1m) during the studied period. Furthermore, temporal variability of temperature shows seasonal variation with a minimum in February and maximum in August. This confirms that episodic events have a negligible effect on spatial and temporal variation of temperature in the subsurface layer. Further analysis will include application of EOF on the salinity, density and total

Measurements of Sediment Transport in the Western Adriatic Sea

Science.gov (United States)

Sherwood, C. R.; Hill, P. S.

2003-12-01

Instrumented bottom tripods were deployed at two depths (10 and 20 m) off the mouth of the Chienti River in the western Adriatic Sea from November 2002 to May 2003 as part of the EuroSTRATAFORM Po and Apennine Sediment Transport and Accumulation (PASTA) Experiment. Waves, currents, and proxies for suspended-sediment concentrations were measured with upward-looking acoustic Doppler current meters, downward looking pulse-coherent acoustic Doppler profilers, single-point acoustic Doppler velocimeters, and acoustic and optical backscatter sensors. Flow was dominated by the western Adriatic coastal current (WACC) during the experiment. Mean southward alongshore velocity 2 m below the surface was 0.10 m/s at the 10-m site and 0.23 m/s at the 20-m site, and flow was modulated by tides, winds, and fluctuating riverflow. The largest waves (3 m significant height) were generated by winds from the southeast during a Sirocco event in late November that generated one of the few episodes of sustained northward flow and sediment transport. Most of the time, however, sediment resuspension and transport was dominated by Bora events, when downwelling-favorable winds from the northeast generated waves that resuspended sediment and simultaneously enhanced southward flow in the WACC. Mean flow near the bottom was slightly offshore at the 20-m site (0.01 m/s at 3 m above the bottom), but there was no significant correlation between downwelling and wave-induced resuspension, and cross-shelf sediment fluxes were small. The combination of persistent southward flow with low rates of cross-shelf leakage makes the WACC an efficient conduit for sediment past the Chienti region. If these observations are representative of typical winter conditions along the entire western Adriatic, they may help explain the enigmatic development of Holocene shelf-edge clinoforms that have formed hundreds of kilometers south of the Po River, which provides most of the sediment to the Adriatic Sea. Future data

Fundamental Adriatic seiche recorded by current meters

Directory of Open Access Journals (Sweden)

N. Leder

2004-04-01

Full Text Available Currents recorded at two stations positioned at the Adriatic shelf break between 17 February and 6 March 1989 were considered. They provided the first evidence of current variability related to the Adriatic-wide seiches. Current spectra were dominated by a peak at 21.1h – a well-known period of the fundamental Adriatic mode. Amplitudes of oscillations were considerable, occasionally greater than 30cm/s. Both along- and cross-basin currents were recorded, thus signalling the importance of rotational effects. Comparison of the current data with the sea-level measurements performed simultaneously along the east Adriatic coast showed that the 21-h currents flowing in the Adriatic preceded sea levels by a quarter of a cycle, as would be expected from a simple model of bay seiches. Sea-level amplitudes reached 40cm in the North Adriatic, thus marking the event as one of the strongest on record. Seiching was triggered by a suddenly changing sirocco wind, as is usually the case in the Adriatic. The most important features of the seiche event were reproduced with a two-dimensional hydrodynamic model of the Adriatic Sea, forced by the sea-level residuals measured at Otranto and the air pressure and wind data recorded at Lastovo. The model showed that the seiche-related currents were relatively strong in the area where the current measurements were performed and further north – between Zadar and Ancona. Key words. Oceanography: general (continental shelf processes – Oceanography: physical (sea-level variations, currents

A multidisciplinary environmental integrated approach to better understand the Tegnue Reefs formation, offshore Chioggia, Northern Adriatic Sea.

Science.gov (United States)

Bergamasco, Andrea; Donnici, Sandra; Tosi, Luigi; Tagliapietra, Davide; Zaggia, Luca; Bonaldo, Davide; Braga, Federica; Da Lio, Cristina; Keppel, Erica; Lorenzetti, Giuliano; Manfè, Giorgia; Franceschini, Gianluca; Giovanardi, Otello; Carol, Eleonora; Fornaro, Elena; Grant, Carley

2014-05-01

, and benthic invertebrates like bryozoans, mollusks, serpulids and corals also contribute to the final building of the status of Tegnue's environment, but we want to demonstrate that the in first stage of consolidation abiotic phenomena could have played a major role. In order to prove our thesis a series of ground water sampling as well as rock sampling and sediment cores were carried out. The poster illustrates the overall ongoing program as well as some work in progress and first results from field cruise. Acknowledgments This work was supported by the Municipality of Chioggia through the Tegnue Project and partially by the Flagship Project RITMARE - The Italian Research for the Sea - coordinated by the Italian National Research Council and funded by the Italian Ministry of Education, University and Research within the National Research Program 2011-2013, and by the Scientific Cooperation Agreement between the CONICET (Argentina) - CNR (Italy), Program 2013-2014, Project 'Fresh-saltwaters in high-value coastlands: from the hydrogeophysical/geochemical characterization of the present interactions to the modeling quantification of the expected effects of climate changes'. References - Bonardi, M., Tosi, L. 2000. Indagini preliminari su alcune formazioni di sabbie cementate nella laguna di Venezia. In: La Ricerca Scientifica Per Venezia. Il Progetto Sistema Lagunare Veneziano, Modellistica del Sistema Lagunare Studio di Impatto Ambientale. Istituto Veneto di Scienze, Lettere ed Arti, Vol. II, Tomo II, p. 967-974, Venezia, ISBN: 88-86166-82-6. - Bonardi, M., Tosi, L., Rizzetto, F., Brancolini, G., Baradello, L. 2006. Effects of climate changes on the late Pleistocene and Holocene sediments of the Venice Lagoon, Italy. Journal of Coastal Research, SI 39, 279-284. - Casellato S., Stefanon A. 2008. Coralligenous habitat in the northern Adriatic Sea: an overview. Marine Ecology, 29: 321-341. - Gabbianelli, G., Colantoni, P., Degetto, S., Dinelli, E., Lucchini, F. 1997

Application of a bioeconomic model for supporting the management process of the small pelagic fishery in the Veneto Region, northern Adriatic Sea, Italy

Directory of Open Access Journals (Sweden)

Silvia Silvestri

2009-09-01

Full Text Available We explore the sustainability of the small pelagics fishery in the northern Adriatic sea, northeastern Italy, by means of a bioeconomic simulation model. This model reproduces the biological and economic conditions in which the fisheries occur. Starting from an initial condition (2004, the simulation model incorporates the biological and economic processes of the resources and the fishing fleet and computes the most probable future trajectory of the system under different management conditions. We analysed the projection of selected indicators (biomass, recruitment, catches, profits under four different management scenarios based on effort control, and we assessed the performance of these management measures against the current situation. The four scenarios were: i increase in fuel price, ii reduction in fuel price, iii limiting the number of days at sea, and iv extending the fishing period. Each management event was introduced in the third year of the simulation. For each scenario a stochastic simulation was carried out. Our results show that the impact of each management measure tested was not homogeneous across the fleet. In particular, comparatively smaller vessels generally display narrower profit margins and tend to be more sensitive to negative shocks, reinforcing the idea that management measures should be calibrated by stratifying the fleet before implementation.

POTENTIAL FOR DEVELOPMENT OF INTEGRATED MULTI-TROPHIC AQUACULTURE (IMTA IN THE ADRIATIC SEA

Directory of Open Access Journals (Sweden)

Danijel Kanski

2012-12-01

Full Text Available Over recent years, scientific interest for investigating ecological, economical and social effects of Integrated Multi-trophic Aquaculture (IMTA has increased worldwide. Its development in the Mediterranean, including the Adriatic Sea, is still in the early stages. The main obstacle preventing IMTA to be commercially adopted is the lack of scientific information on choosing compatible species, knowing the carrying capacity of a production area and interactions between species feeding at different trophic levels, as well as its socio–economic impacts. Current experience in the area is based on smaller experimental studies of local importance but they generally give a good insight into potential of IMTA and its interactions with the environment. The aim of this paper was to overview current literature and experiences worldwide and to review the potential for adopting IMTA principles in the Adriatic Sea.

Review of Development of Adriatic Marine Radioecology

International Nuclear Information System (INIS)

Branica, G.; Franic, Z.; Marovic, G.; Petrinec, B.; Hanzek, B.

2013-01-01

This paper presents a historical overview and some research results of radioactive contamination of the Adriatic Sea and coastal areas caused by natural and anthropogenic radionuclides, with emphasis on the eastern Adriatic coast. The results of the first known survey of radioactivity of the Adriatic Sea have been published in 1909, by Prof. Dr. Peter Salcher from the Imperial and Royal Naval Academy (k.u.k. Marine Akademie) in the city of Rijeka. These were compared with similar studies conducted in the Atlantic Ocean. Systematic radioecological research of the eastern coast of the Adriatic Sea that began in 1961 at three locations (Rovinj, Split and Dubrovnik) have been organized by the Directorate for Civil Protection of the State Secretariat for people's defence, targeting the activity concentrations of fission products 90Sr and 137Cs in seawater. Editing and standardization of data has been coordinated by the engineer Velimir Popovic, an associate of the Institute for Medical Research and Occupational Health.Nowadays, contemporary radieocological monitoring in the Republic of Croatia related to the Adriatic Sea today is conducted by Radiation Protection Unit of the Institute for Medical Research and Occupational Health within the framework of 'Monitoring of environmental radioactivity in the Republic of Croatia' and the scientific project R adioecology of the Adriatic sea and Coastal Areas , project no. 022-0222882-2823 funded by the Ministry of Science, Education and Sports of the Republic of Croatia.(author)

Wintertime dynamics in the coastal northeastern Adriatic Sea: the NAdEx 2015 experiment

Directory of Open Access Journals (Sweden)

I. Vilibić

2018-03-01

Full Text Available The paper investigates the wintertime dynamics of the coastal northeastern Adriatic Sea and is based on numerical modelling and in situ data collected through field campaigns executed during the winter and spring of 2015. The data were collected with a variety of instruments and platforms (acoustic Doppler current profilers, conductivity–temperature–depth probes, glider, profiling float and are accompanied by the atmosphere–ocean ALADIN/ROMS modelling system. The research focused on the dense-water formation (DWF, thermal changes, circulation, and water exchange between the coastal and open Adriatic. According to both observations and modelling results, dense waters are formed in the northeastern coastal Adriatic during cold bora outbreaks. However, the dense water formed in this coastal region has lower densities than the dense water formed in the open Adriatic due to lower salinities. Since the coastal area is deeper than the open Adriatic, the observations indicate (i balanced inward–outward exchange at the deep connecting channels of denser waters coming from the open Adriatic DWF site and less-dense waters coming from the coastal region and (ii outward flow of less-dense waters dominating in the intermediate and surface layers. The latter phenomenon was confirmed by the model, even if it significantly underestimates the currents and transports in the connecting channels. The median residence time of the coastal area is estimated to be approximately 20 days, indicating that the coastal area may be renewed relatively quickly by the open Adriatic waters. The data that were obtained represent a comprehensive marine dataset that can be used to calibrate atmospheric and oceanic numerical models and point to several interesting phenomena to be investigated in the future.

Wintertime dynamics in the coastal northeastern Adriatic Sea: the NAdEx 2015 experiment

Science.gov (United States)

Vilibić, Ivica; Mihanović, Hrvoje; Janeković, Ivica; Denamiel, Cléa; Poulain, Pierre-Marie; Orlić, Mirko; Dunić, Natalija; Dadić, Vlado; Pasarić, Mira; Muslim, Stipe; Gerin, Riccardo; Matić, Frano; Šepić, Jadranka; Mauri, Elena; Kokkini, Zoi; Tudor, Martina; Kovač, Žarko; Džoić, Tomislav

2018-03-01

The paper investigates the wintertime dynamics of the coastal northeastern Adriatic Sea and is based on numerical modelling and in situ data collected through field campaigns executed during the winter and spring of 2015. The data were collected with a variety of instruments and platforms (acoustic Doppler current profilers, conductivity-temperature-depth probes, glider, profiling float) and are accompanied by the atmosphere-ocean ALADIN/ROMS modelling system. The research focused on the dense-water formation (DWF), thermal changes, circulation, and water exchange between the coastal and open Adriatic. According to both observations and modelling results, dense waters are formed in the northeastern coastal Adriatic during cold bora outbreaks. However, the dense water formed in this coastal region has lower densities than the dense water formed in the open Adriatic due to lower salinities. Since the coastal area is deeper than the open Adriatic, the observations indicate (i) balanced inward-outward exchange at the deep connecting channels of denser waters coming from the open Adriatic DWF site and less-dense waters coming from the coastal region and (ii) outward flow of less-dense waters dominating in the intermediate and surface layers. The latter phenomenon was confirmed by the model, even if it significantly underestimates the currents and transports in the connecting channels. The median residence time of the coastal area is estimated to be approximately 20 days, indicating that the coastal area may be renewed relatively quickly by the open Adriatic waters. The data that were obtained represent a comprehensive marine dataset that can be used to calibrate atmospheric and oceanic numerical models and point to several interesting phenomena to be investigated in the future.

Adriatic Sea surface temperature and ocean colour variability during the MFSPP

Directory of Open Access Journals (Sweden)

E. Böhm

2003-01-01

Full Text Available Two years and six months of night-time Advanced Very High Resolution Radiometer (AVHRR sea surface temperature (SST and daytime Sea viewing Wide Field of view Sensor (SeaWiFS data collected during the MFSPP have been used to examine spatial and temporal variability of SST and chlorophyll (Chl in the Adriatic Sea. Flows along the Albanian and the Italian coasts can be distinguished year-round in the monthly averaged Chl but only in the colder months in the monthly averaged SST’s. The Chl monthly-averaged fields supply less information on circulation features away from coastal boundaries and where conditions are generally oligotrophic, except for the early spring bloom in the Southern Adriatic Gyre. To better characterise the year-to-year and seasonal variability, exploratory data analysis techniques, particularly the plotting of multiple Chl-SST histograms, are employed to make joint quantitative use of monthly-averaged fields. Modal water mass (MW, corresponding to the Chl-SST pairs in the neighbourhood of the maximum of each monthly histogram, are chosen to represent the temporal and spatial evolution of the prevalent processes and their variability in the Adriatic Sea. Over an annual cycle, the MW followed a triangular path with the most pronounced seasonal and interannual variations in both Chl-SST properties and spatial distributions of the MW in the colder part of the year. The winter of 1999 is the colder (by at least 0.5°C and most eutrophic (by 0.2 mg/m 3. The fall of the year 2000 is characterised by the lack of cooling in the month of November that was observed in the previous year. In addition to characterising the MW, the two-dimensional histogram technique allows a distinction to be made between different months in terms of the spread of SST values at a given Chl concentration. During spring and summer, the spread is minimal indicating surface homothermal conditions. In fall and winter, on the other hand, a spread of points

3D Architecture and evolution of the Po Plain-Northern Adriatic Foreland basin during Plio-Pleistocene time

Science.gov (United States)

Amadori, Chiara; Toscani, Giovanni; Ghielmi, Manlio; Maesano, Francesco Emanuele; D'Ambrogi, Chiara; Lombardi, Stefano; Milanesi, Riccardo; Panara, Yuri; Di Giulio, Andrea

2017-04-01

The Pliocene-Pleistocene tectonic and sedimentary evolution of the eastern Po Plain and northern Adriatic Foreland Basin (PPAF) (extended ca. 35,000 km2) was the consequence of severe Northern Apennine compressional activity and climate-driven eustatic changes. According with the 2D seismic interpretation, facies analysis and sequence stratigraphy approach by Ghielmi et al. (2013 and references therein), these tectono-eustatic phases generated six basin-scale unconformities referred as Base Pliocene (PL1), Intra-Zanclean (PL2), Intra-Piacenzian (PL3), Gelasian (PL4), Base Calabrian (PS1) and Late Calabrian (PS2). We present a basin-wide detailed 3D model of the PPAF region, derived from the interpretation of these unconformities in a dense network of seismic lines (ca. 6,000 km) correlated with more than 200 well stratigraphies (courtesy of ENI E&P). The initial 3D time-model has been time-to-depth converted using the 3D velocity model created with Vel-IO 3D, a tool for 3D depth conversions and then validated and integrated with depth domain dataset from bibliography and well log. Resultant isobath and isopach maps are produced to inspect step-by-step the basin paleogeographic evolution; it occurred through alternating stages of simple and fragmented foredeeps. Changes in the basin geometry through time, from the inner sector located in the Emilia-Romagna Apennines to the outermost region (Veneto and northern Adriatic Sea), were marked by repeated phases of outward migration of two large deep depocenters located in front of Emilia arcs on the west, and in front of Ferrara-Romagna thrusts on the east. During late Pliocene-early Pleistocene, the inner side of the Emilia-Romagna arcs evolved into an elongated deep thrust-top basin due to a strong foredeep fragmentation then, an overall tectono-stratigraphic analysis shows also a decreasing trend of tectonic intensity of the Northern Apennine since Pleistocene until present.

Paleohydrology reconstruction and Holocene climate variability in the South Adriatic Sea

Directory of Open Access Journals (Sweden)

G. Siani

2013-02-01

Full Text Available Holocene paleohydrology reconstruction is derived combining planktonic and benthic stable oxygen and carbon isotopes, sea surface temperatures (SSTs and oxygen isotope composition of seawater (δ18Ow from a high sedimentation core collected in the South Adriatic Sea (SAS. Core chronology is based on 10 AMS 14C measures on planktonic foraminifera and tephra layers. Results reveal two contrasted paleohydrological periods that reflect (i a marked lowering of δ18Ow/salinity during the early to mid-Holocene (11.5 ka to 6.3 ka, including the two-step sapropel S1 deposition, followed during the mid- to upper Holocene by (ii a prevailing period of increased salinity and enhanced arid conditions in the South Adriatic Basin. Superimposed on these trends, short-term centennial-scale hydrological events punctuated the Holocene period in the SAS. During the early to mid-Holocene, two main SST coolings together with prominent δ18Ow/salinity lowering delineate the sapropel S1 interruption and the post-sapropel phase between 7.3 to 6.3 ka. After 6 ka, centennial-scale δ18Ow and G. bulloides δ13C lowering, mostly centered between 3 to 0.6 ka, reflect short-term hydrological changes related to more intensive runoff of the Po and/or Apennine rivers. These short-term events, even of lesser amplitude compared to the early to mid-Holocene period, may have induced a lowering of sea surface density and consequently reduced and/or inhibited the formation of deep bottom waters in the SAS. Comparison of the emerging centennial- to millennial-scale hydrological record with previous climatic records from the central Mediterranean area and north of the Alps reveal possible synchronicities (within the radiocarbon-dating uncertainty between phases of lower salinity in the SAS and periods of wetter climatic conditions around the north-central Adriatic Sea. Finally, wavelet analyses provide new clues about the potential origin of climate variability in the SAS, confirming

Macro- and megafauna recorded in the submarine Bari Canyon (southern Adriatic, Mediterranean Sea using different tools

Directory of Open Access Journals (Sweden)

G. D'ONGHIA

2015-01-01

Full Text Available Macro- and megafauna were recorded in the submarine Bari Canyon (southern Adriatic Sea, Mediterranean Sea during an oceanographic cruise carried out in May-June 2012 and an experimental fishing survey conducted in November 2013. During the former, a total of 20 benthic samples were taken using a Van Veen grab at depths between 268 and 770 m and 4 deployments of a baited lander, for about 43 hours of video records, were carried out at depths between 443 and 788 m. During the latter, 8 longline fishing operations were conducted from 338 down to 612 m. Eighty-five living benthic and benthopelagic species were recorded: 29 Porifera, 1 Cnidaria, 2 Mollusca, 11 Annelida, 1 Arthropoda, 19 Bryozoa, 3 Echinodermata and 19 Chordata. A total of 51 species are new records for the Bari Canyon, 29 new records for the Adriatic Sea. Among the Porifera Cerbaris curvispiculifer is a new addition for the Italian Sponge Fauna. The first certain record of living specimens for the bryozoan Crisia tenella longinodata is reported. A total of 6 Mediterranean endemic species have been identified: 4 Porifera and 2 Annelida. The bathymetric range of some species has been extended. New information acquired for deep sea species confirms their importance in the structure of cold-water coral communities. This study has updated the knowledge on the biodiversity of the Adriatic Sea, as well as of the Bari Canyon in particular, one of the sites designated as “jewels of the Mediterranean” for which urgent conservation measures are needed.

On the record of Red seabream Pagrus major (Temminck and Schlegel,1843 (Osteichthyes: Sparidae in the Adriatic Sea

Directory of Open Access Journals (Sweden)

Jakov Dulcic

2007-03-01

Full Text Available One specimen of red seabream Pagrus major, 44.9 cm total length, was caught in the eastern middle Adriatic (Island Molat, Cape Bonaster by long-line hook at a depth of about 20 m on a hard rocky bottom on 25 September 2004. It is the first record of this species in the Adriatic Sea and Mediterranean area.

An observatory system for physical and biogeochemical parameters in the northern Adriatic Sea: the "Acqua Alta" oceanographic platform

Science.gov (United States)

Benetazzo, Alvise; Barbariol, Francesco; Bastianini, Mauro; Bergamasco, Andrea; Bergamasco, Filippo; Bernardi Aubry, Fabrizio; Bertotti, Luciana; Bonaldo, Davide; Cavaleri, Luigi; Carniel, Sandro; Falcieri, Francesco M.; Finotto, Stefania; Lester, Graham; Licer, Matjaz; Malacic, Vlado; Minuzzo, Tiziano; Sclavo, Mauro

2015-04-01

The history of the "Acqua Alta" oceanographic platform (http://www.ismar.cnr.it/infrastructures/piattaforma-acqua-alta) started more than forty years ago, shortly after the dramatic surge that affected the city of Venice in late 1966. Since then, benefiting also from recent funding acquired within the National Flagship Project RITMARE, great efforts have been devoted to monitor the oceanographic and atmospheric conditions in the Northern Adriatic Sea (NA), in the proximity of the Venice lagoon. Nowadays the "Acqua Alta", located on a 16 m depth area, represents a success story of the Institute of Marine Sciences (ISMAR) of the Italian National Research Council (CNR), that manages the structure and used collected data to improve the knowledge of the fragile sea environment that surrounds the Venetian littoral. The directional wave observations started in 1979, representing one of the world longest continuous series. On the sea surface, waves are now routinely observed by means of a submerged acoustic-Doppler system that provides burst of directional wave data, including significant wave height, mean wave period and direction of propagation. Currently these wave parameters are integrated with the data collected by a stereo-video system (namely Wave Acquisition Stereo System, WASS) that provides the 3-D profile of the wavy sea surface. WASS data are unleashing a "new view" for ocean waves providing the complete space-time dynamics of wave groups. Moreover, a series of multiparameters probes permits to measure the vertical distribution of sea temperature (at nine depths from the surface to the bottom), salinity (three positions), dissolved oxygen (two positions), and turbidity close to the sea bottom. The collected data are continuously used to track the water masses that enter, leave, and are produced within the NA. A striking example is provided by the temperature and salinity data used to follow the exceptional dense water formation that occurred in this basin

Boosting Blue Growth in a Mild Sea: Analysis of the Synergies Produced by a Multi-Purpose Offshore Installation in the Northern Adriatic, Italy

Directory of Open Access Journals (Sweden)

Barbara Zanuttigh

2015-05-01

Full Text Available In the near future, the oceans will be subjected to a massive development of marine infrastructures, including offshore wind, tidal and wave energy farms and constructions for marine aquaculture. The development of these facilities will unavoidably exert environmental pressures on marine ecosystems. It is therefore crucial that the economic costs, the use of marine space and the environmental impacts of these activities remain within acceptable limits. Moreover, the installation of arrays of wave energy devices is still far from being economically feasible due to many combined aspects, such as immature technologies for energy conversion, local energy storage and moorings. Therefore, multi-purpose solutions combining renewable energy from the sea (wind, wave, tide, aquaculture and transportation facilities can be considered as a challenging, yet advantageous, way to boost blue growth. This would be due to the sharing of the costs of installation and using the produced energy locally to feed the different functionalities and optimizing marine spatial planning. This paper focuses on the synergies that may be produced by a multi-purpose offshore installation in a relatively calm sea, i.e., the Northern Adriatic Sea, Italy, and specifically offshore Venice. It analyzes the combination of aquaculture, energy production from wind and waves, and energy storage or transfer. Alternative solutions are evaluated based on specific criteria, including the maturity of the technology, the environmental impact, the induced risks and the costs. Based on expert judgment, the alternatives are ranked and a preliminary layout of the selected multi-purpose installation for the case study is proposed, to further allow the exploitation of the synergies among different functionalities.

Fluxes and burial of particulate organic carbon along the Adriatic mud-wedge (Mediterranean Sea)

Science.gov (United States)

Tesi, T.; Langone, L.; Giani, M.; Ravaioli, M.; Miserocchi, S.

2012-04-01

Clinoform-shaped deposits are ubiquitous sedimentological bodies of modern continental margins, including both carbonate and silicoclastic platforms. They formed after the attainment of the modern sea level high-stand (mid-late Holocene) when river outlets and shoreline migrated landward. As clinoform-shape deposits are essential building blocks of the infill of sedimentary basins, they are sites of intense organic carbon (OC) deposition and account for a significant fraction of OC burial in the ocean during interglacial periods. In this study, we focused on sigmoid clinoforms that are generally associated with low-energy environments. In particular, we characterized the modern accumulation and burial of OC along the late-Holocene sigmoid in the Western Adriatic Sea (Mediterranean Sea). This sedimentary body consists of a mud wedge recognizable on seismic profiles as a progradational unit lying on top the maximum flooding surface that marks the time of maximum landward shift of the shoreline attained around 5.5 kyr cal BP. In the last two decades, several projects have investigated sediment dynamics and organic geochemistry along the Adriatic mud wedge (e.g., PRISMA, EURODELTA, EuroSTRATAFORM, PASTA, CIPE, VECTOR). All these studies increased our understanding of strata formation and organic matter cycling in this epicontinental margin. The overarching goal of this study was to combine the results gained during these projects with newly acquired data to assess fluxes to seabed and burial efficiency of organic carbon along the uppermost strata of the Adriatic mud-wedge. Our study benefited of an extensive number of radionuclide-based (Pb-210, and Cs-137) sediment accumulation rates and numerous biogeochemical data of surface sediments and sediment cores (organic carbon, total nitrogen, radiocarbon measurements, carbon stable isotopes, and biomarkers). In addition, because the accumulation of river-borne sediment may or may not be linked to a specific source, another

The role of local and external factors in determining the interannual sea level variability of the Adriatic and Black Seas during the 20th century.

Science.gov (United States)

Scarascia, Luca; Lionello, Piero

2016-04-01

The Adriatic Sea and the Black Sea are two semienclosed basins connected to the Mediterranean Sea by the Otranto and the Bosporus straits, respectively. This work aims to reconstruction the sea level for both basins in the 20th century and to investigate main sources of interannual variability. Using 7 tide gauge timeseries located along the Adriatic coast and 5 along the Black Sea coast, provided by the PSMSL (Permanent service of mean sea level), a seamless sea level timeseries (1900-2009) has been obtained for each basin on the basis of statistical procedure involving PCA and Least Square Method. The comparison with satellite data in the period 1993 - 2009 confirms that these are reliable representations of the observed sea level for the whole basin, showing a great agreement with a correlation value of 0.87 and 0.72 for Adriatic and Black Sea respectively. The sea level has been decomposed in various contributions in order to analyze the role of the factors responsible for its interannual variability. The annual cycles of the local effect of pressure (inverse barometer effect IB), of the steric effect due to temperature and salinity variation and of the wind effect have been computed. The largest contribute for the Adriatic Sea is due to the wind, whilst inverse barometer effect plays a minor role and the steric effect seems to be almost negligible. For the Black Sea, on the contrary, wind effect is negligible, and the largest source of variability is due to the Danube river, which is estimated from the available discharge data of Sulina (one of the exits of the Danube delta. Steric and IB effects play both a minor role in this basin. A linear regression model, built considering as predictor the SLP gradient identified at large scale after having carried out the correlation analysis, is capable to explain a further percentage of variability (about 20-25%) of the sea level after subtracting all the factors considered above. Finally, residual sea levels show a

Aliphatic and polycyclic aromatic hydrocarbons in Gulf of Trieste sediments (northern Adriatic): potential impacts of maritime traffic.

Science.gov (United States)

Bajt, Oliver

2014-09-01

The Gulf of Trieste (northern Adriatic) is one of the most urbanized and industrialized areas in the northern Adriatic, with intense maritime traffic experienced at multiple ports. The impact of maritime traffic on contamination by hydrocarbons in this area was assessed. Concentrations of hydrocarbons were higher near the expected contamination sources and still elevated in the adjacent offshore areas. Aliphatic hydrocarbons were mainly of petrogenic origin, with some contribution of biogenic origin. A continuous contamination by aliphatic hydrocarbons and degradation processes were hypothesized. Concentrations of total polycyclic aromatic hydrocarbons (PAH) were generally greater near the contamination sources. Compared to the prevailing pyrolytic origin, the petrogenic PAH origin seemed to be less important, but not negligible. Results revealed that intensive maritime traffic is a probable source of contamination by hydrocarbons in the investigated area, which is largely limited to areas near the contamination sources.

First record of small tropical calanoid copepod Parvocalanus crassirostris (Copepoda, Calanoida, Paracalanidae in the Adriatic Sea

Directory of Open Access Journals (Sweden)

O. VIDJAK

2016-09-01

Full Text Available In December 2014 the adult females and copepodites of alien paracalanid copepod Parvocalanus crassirostris were identified in the Central Adriatic port of Šibenik. The most probable transmission vector for this small copepod were ballast waters from the cargo ships that are regularly discharged at these locations. This paper is focused on P. crassirostris morphology and the state of population in the port of Šibenik. The possible path of introduction of Parvocalanus crassirostris into the Adriatic Sea is also discussed.

Interactive effects of vegetation and sediment properties on erosion of salt marshes in the Northern Adriatic Sea.

Science.gov (United States)

Lo, V B; Bouma, T J; van Belzen, J; Van Colen, C; Airoldi, L

2017-10-01

We investigated how lateral erosion control, measured by novel photogrammetry techniques, is modified by the presence of Spartina spp. vegetation, sediment grain size, and the nutrient status of salt marshes across 230 km of the Italian Northern Adriatic coastline. Spartina spp. vegetation reduced erosion across our study sites. The effect was more pronounced in sandy soils, where erosion was reduced by 80% compared to 17% in silty soils. Erosion resistance was also enhanced by Spartina spp. root biomass. In the absence of vegetation, erosion resistance was enhanced by silt content, with mean erosion 72% lower in silty vs. sandy soils. We found no relevant relationships with nutrient status, likely due to overall high nutrient concentrations and low C:N ratios across all sites. Our results contribute to quantifying coastal protection ecosystem services provided by salt marshes in both sandy and silty sediments. Copyright © 2017 Elsevier Ltd. All rights reserved.

Biodiversity of culturable heterotrophic bacteria in the Southern Adriatic Sea Italian coastal waters

Directory of Open Access Journals (Sweden)

Loredana Stabili

2004-04-01

Full Text Available The qualitative and quantitative composition of culturable heterotrophic bacteria in water samples from the Southern Adriatic Sea of Italy was examined. Water samples were collected monthly, for a year, at 16 stations along the coast line between Brindisi and Santa Maria di Leuca. The results obtained described the heterotrophic bacterial community over an annual cycle. Mean values of bacterial densities were 5.3 x 104 CFUml-1 in Brindisi, 5.8 x 104 CFUml-1 in S. Cataldo, 4.3 x 104 CFUml-1 in Otranto and 6.7 x 104 CFUml-1 in S. M. di Leuca. The differences in bacterial densities between the sites considered were estimated. The hydrodynamic circulation, the trophism and the geographical position of the examined sites contribute to justify the different bacterial density trends. The bacterial community consisted mainly of the genera Aeromonas, Pseudomonas, Photobacterium and Flavobacterium. The Enterobacteriaceae represented a considerable fraction of the bacterial community in the Southern Adriatic Sea. Bacilli were predominant among the Gram positive bacteria. The enzymatic versatility of the observed genera suggest their importance in organic matter turnover of this oligotrophic ecosystem.

Holocene vegetation and climate changes in the central Mediterranean inferred from a high-resolution marine pollen record (Adriatic Sea

Directory of Open Access Journals (Sweden)

N. Combourieu-Nebout

2013-09-01

Full Text Available The high-resolution multiproxy study of the Adriatic marine core MD 90-917 provides new insights to reconstruct vegetation and regional climate changes over the southcentral Mediterranean during the Younger Dryas (YD and Holocene. Pollen records show the rapid forest colonization of the Italian and Balkan borderlands and the gradual installation of the Mediterranean association during the Holocene. Quantitative estimates based on pollen data provide Holocene precipitations and temperatures in the Adriatic Sea using a multi-method approach. Clay mineral ratios from the same core reflect the relative contributions of riverine (illite and smectite and eolian (kaolinite contributions to the site, and thus act as an additional proxy with which to evaluate precipitation changes in the Holocene. Vegetation climate reconstructions show the response to the Preboreal oscillation (PBO, most likely driven by changes in temperature and seasonal precipitation, which is linked to increasing river inputs from Adriatic rivers recorded by increase in clay mineral contribution to marine sediments. Pollen-inferred temperature declines during the early–mid Holocene, then increases during the mid–late Holocene, similar to southwestern Mediterranean climatic patterns during the Holocene. Several short vegetation and climatic events appear in the record, indicating the sensitivity of vegetation in the region to millennial-scale variability. Reconstructed summer precipitation shows a regional maximum (170–200 mm between 8000 and 7000 similar to the general pattern across southern Europe. Two important shifts in vegetation occur at 7700 cal yr BP (calendar years before present and between 7500 and 7000 cal yr BP and are correlated with increased river inputs around the Adriatic Basin respectively from the northern (7700 event and from the central Adriatic borderlands (7500–7000 event. During the mid-Holocene, the wet summers lead to permanent moisture all year

Spatio-temporal reproducibility of the microbial food web structure associated with the change in temperature: Long-term observations in the Adriatic Sea

Science.gov (United States)

Šolić, Mladen; Grbec, Branka; Matić, Frano; Šantić, Danijela; Šestanović, Stefanija; Ninčević Gladan, Živana; Bojanić, Natalia; Ordulj, Marin; Jozić, Slaven; Vrdoljak, Ana

2018-02-01

Global and atmospheric climate change is altering the thermal conditions in the Adriatic Sea and, consequently, the marine ecosystem. Along the eastern Adriatic coast sea surface temperature (SST) increased by an average of 1.03 °C during the period from 1979 to 2015, while in the recent period, starting from 2008, a strong upward almost linear trend of 0.013 °C/month was noted. Being mainly oligotrophic, the middle Adriatic Sea is characterized by the important role played by the microbial food web in the production and transfer of biomass and energy towards higher trophic levels. It is very important to understand the effect of warming on microbial communities, since small temperature increases in surface seawater can greatly modify the microbial role in the global carbon cycle. In this study, the Self-Organizing Map (SOM) procedure was used to analyse the time series of a number of microbial parameters at two stations with different trophic status in the central Adriatic Sea. The results show that responses of the microbial food web (MFW) structure to temperature changes are reproducible in time. Furthermore, qualitatively similar changes in the structure of the MFW occurred regardless of the trophic status. The rise in temperature was associated with: (1) the increasing importance of microbial heterotrophic activities (increase bacterial growth and bacterial predator abundance, particularly heterotrophic nanoflagellates) and (2) the increasing importance of autotrophic picoplankton (APP) in the MFW.

Benthic fluxes of mercury during redox changes in pristine coastal marine sediments from the Gulf of Trieste (northern Adriatic Sea)

Energy Technology Data Exchange (ETDEWEB)

Koron, Neza [National Institute of Biology, Piran (Slovenia). Marine Biological Section; Faganeli, Jadran [National Institute of Biology, Piran (Slovenia). Marine Biological Section; Jozef Stefan Institute, Ljubljana (Slovenia). Dept. of Environmental Sciences

2012-12-15

Purpose: The Gulf of Trieste (northern Adriatic Sea) is an example of a coastal environment contaminated with mercury (Hg). Contamination is a consequence of nearly 500 years of activity at the Idrija Mine (western Slovenia), which is the second largest Hg mine in the world. Oxygen depletion can be common in the Gulf of Trieste due to late summer stratification of the water column and accumulation of labile organic matter. Since changing redox conditions can have an impact on Hg transformations, we studied the effect of oxygen depletion, in parallel with sulphide, iron (Fe), manganese (Mn), fluorescent dissolved organic matter (FDOM) and nitrogen (N) and phosphorus (P) availability, on total Hg and methylmercury (MeHg) fluxes from sediments. Materials and methods: Pore water concentrations and benthic fluxes of total dissolved Hg and MeHg were studied in situ and in microcosm laboratory experiments using flux chambers encompassing three different stages: oxic, anoxic and reoxidation. Results and discussion: Our experiments showed that in the oxic stage there were small effluxes of MeHg to the water column, which increased in the anoxic stage and dropped rapidly in a subsequent reoxic stage, showing influx. Our results support the hypothesis that MeHg desorption from reduced metal hydroxides under anoxic conditions, and co-precipitation with Fe-oxides and MeHg demethylation in the reoxidation stage, may play a major role in determining MeHg benthic fluxes. For Hg and MeHg, it appears that there is little relationship between their pore water distribution and flux and that of FDOM, i.e. humics. Conclusions: The results indicate that there was no significant difference in Hg and MeHg pore water levels and their benthic fluxes between the contaminated northern and central parts of the Gulf of Trieste and the pristine southern part. This suggests that shallow and stratified coastal marine environments, in general, represent areas with a risk of high benthic release of

Histological and Morphological Aspects of Reproduction in Male Blackspotted Smooth-Hound Mustelus punctulatus in the Adriatic Sea (Eastern Mediterranean Sea

Directory of Open Access Journals (Sweden)

Romana Gračan

2016-01-01

Full Text Available We present first data on reproductive biology of male blackspotted smooth-hound Mustelus punctulatus in the Adriatic Sea and first histological examination of gonads at different maturation stages and seasonal cycles for this species. We collected samples from 117 male specimens of M. punctulatus ranging in length from 44.6 to 126.5 cm, caught by commercial bottom trawls in the North-Central Adriatic Sea. Microscopic observation revealed a diametric development of testes, in which round-shaped spermatocysts have zonal arrangement, showing seven different stages of development. Males began to mature when they were between 61 and 88 cm body length, which was indicated by the presence of functional claspers or appearance of the spermatogenic cysts. While the smallest mature shark was only 80 cm long, all animals longer than 89 cm were sexually mature. The seasonal analysis of the testes indicated that mature spermatozoa dominated in testes during the first half of the year with a peak in May and June, after which followed less active period during July and August.

Downwelling dynamics of the western Adriatic Coastal Current

Science.gov (United States)

Geyer, W. R.; Mullenbach, B. L.; Kineke, G. C.; Sherwood, C. R.; Signell, R. P.; Ogston, A. S.; Puig, P.; Traykovski, P.

2004-12-01

The western Adriatic coastal current (WACC) flows for hundreds of kilometers along the east coast of Italy at speeds of 20 to 100 cm/s. It is fed by the buoyancy input from the Po River and other rivers of the northern Adriatic Sea, with typical freshwater discharge rates of 2000 m**3/s. The Bora winds provide the dominant forcing agent of the WACC during the winter months, resulting in peak southeastward flows reaching 100 cm/s. The energy input of the Bora is principally in the northern Adriatic, and the coastal current response is due mainly to the set up of the pressure field, although there is sometimes an accompanying local component of down-coast winds that further augments the coastal current. Downwelling conditions occur during Bora, with or without local wind-forcing, because the bottom Ekman transport occurs in either case. Downwelling results in destratification of the coastal current, due to both vertical mixing and straining of the cross-shore density gradient. The relative contributions of mixing and straining depends on the value of the Kelvin number K=Lf/(g_Oh)**1/2, where L is the width of the coastal current, f is the Coriolis parameter, g_O is reduced gravity, and h is the plume thickness. For a narrow coastal current (KWACC during Bora events, with strain-induced destratification occurring in less than 24 hours. The straining process limits vertical mixing of the coastal current with the ambient Adriatic water, because once the isopycnals become vertical, no more mixing can occur. This limitation of mixing may explain the persistence of the density anomaly of the coastal current in the presence of high stresses. The straining process also has important implications for sediment transport: destratification allows sediment to be distributed throughout the water column during Bora events, resulting in enhanced down-coast fluxes. The influence of the downwelling dynamics on cross-shore sediment transport is still under examination.

Mass Mortality Events in the NW Adriatic Sea: Phase Shift from Slow- to Fast-Growing Organisms.

Directory of Open Access Journals (Sweden)

Cristina Gioia Di Camillo

Full Text Available Massive outbreaks are increasing all over the world, which are likely related to climate change. The North Adriatic Sea, a sub-basin of the Mediterranean Sea, is a shallow semi-closed sea receiving high nutrients inputs from important rivers. These inputs sustain the highest productive basin of the Mediterranean Sea. Moreover, this area shows a high number of endemisms probably due to the high diversity of environmental conditions and the conspicuous food availability. Here, we documented two massive mortalities (2009 and 2011 and the pattern of recovery of the affected biocoenoses in the next two years. Results show an impressive and fast shift of the benthic assemblage from a biocoenosis mainly composed of slow-growing and long-lived species to a biocoenosis dominated by fast-growing and short-lived species. The sponge Chondrosia reniformis, one of the key species of this assemblage, which had never been involved in previous massive mortality events in the Mediterranean Sea, reduced its coverage by 70%, and only few small specimens survived. All the damaged sponges, together with many associated organisms, were detached by rough-sea conditions, leaving large bare areas on the rocky wall. Almost three years after the disease, the survived specimens of C. reniformis did not increase significantly in size, while the bare areas were colonized by fast-growing species such as stoloniferans, hydrozoans, mussels, algae, serpulids and bryozoans. Cnidarians were more resilient than massive sponges since they quickly recovered in less than one month. In the study area, the last two outbreaks caused a reduction in the filtration efficiency of the local benthic assemblage by over 60%. The analysis of the times series of wave heights and temperature revealed that the conditions in summer 2011 were not so extreme as to justify severe mass mortality, suggesting the occurrence of other factors which triggered the disease. The long-term observations of a

Bora-induced currents corresponding to different synoptic conditions above the Adriatic

Directory of Open Access Journals (Sweden)

G. Beg Paklar

2005-06-01

Full Text Available The Bora wind field is characterised by strong vorticity and divergence. Several numerical experiments, in which an oceanographic model was forced with northeasterly winds having climatological alongshore variability, were performed in order to study the influence of spatial variability in the bora wind field on the surface currents in the northern Adriatic. Numerical model results showed that during bora episodes with lower speeds and fast offshore decay surface currents along transect Rovinj - Po River are predominantly in the downwind direction. On the other hand, during bora episodes with strong intensity and slow offshore decay, a cyclonic gyre due to the pronounced bora alongshore variability is formed in the northernmost part of the Adriatic Sea and the studied transect is influenced by the counter currents. Moreover, bora having a high speed and a short offshore range produces the same effect in the eastern part of the Rovinj - Po River transect as low-speed bora characterised by slow offshore decay. Eulerian current measurements performed in the northern Adriatic during bora episodes characterised by different synoptic conditions supported the numerical model findings. Surface currents during the bora episode of 8-11 February 1984 were directed downwind, whereas during the episode of 12-19 February 1984 they were directed upwind. The first episode was characterised by a deep bora layer with cyclonic activity over the western Mediterranean and Genoa Bay, whereas the second one was accompanied by temperature inversion and a southwesterly tropospheric wind above a shallow bora layer. According to the hydraulic theory developed by Smith (1985, an observed descent of isentropes during the second bora episode led to the stronger acceleration in the bora layer and its larger offshore extent. Different offshore bora decays during studied events were confirmed by a comparison of the wind data originating from the meteorological stations

Variability of PAHs and trace metals in the sediments in relation to environmental characteristics of the bottom layer in the middle Adriatic Sea

Science.gov (United States)

Grilli, Federica; Frapiccini, Emanuela; Campanelli, Alessandra; Guicciardi, Stefano; Marini, Mauro; Marasovic, Ivona; Grbec, Branka; Skejić, Sanda; Ujević, Ivana; Lušić, Jelena

2015-04-01

In the framework of the project PERSEUS (Policy-oriented marine Environmental Research in the Southern EUropean Seas), two interdisciplinary surveys were carried out in April 2013 and April 2014 in the middle Adriatic Sea along the Pescara-Sibenik transect (Jabuka Pits area) and Vieste-Split transect (Palagruza Sill area) with Croatian research vessel "Bios II" and the Italian research vessel "G. Dallaporta", respectively. The main objective of these research cruises was the implementation of the Marine Strategy Framework Directive (MSFD) in the Adriatic region for collecting physical, chemical and biological data in order to get a better understanding of whole Adriatic ecosystem. The two transects are already recognised as a key areas for the interception and the study of dense water modification (Zore-Armanda, 1963; Marini et al., 2006; Grilli et al., 2013). Due to seasonal circulation patterns, they are characterized by high temporal variability of the thermohaline structure (Grbec and Morović, 1997; Vilibić, et al., 2004) and other oceanographic parameters. Long term oceanographic records from the Middle Adriatic enable better understanding of the ecosystem response to changes of atmospheric and sea conditions through physical, chemical and biological processes (Marasović et al., 1995). Several oceanographic parameters relevant and useful for the ecosystem assessment of the two areas (temperature, salinity, density, fluorescence, oxygen, nutrients, chlorophyll, phyto- and zoo-plankton as well as selected pollutants , trace metals and Polycyclic Aromatic Hydrocarbons-PAHs in sediments) were collected. In the present work, the variations of PAHs and trace metals concentration in the marine sediments are presented in relation to the physical and chemical characteristics of the bottom layer. A constant influx of metal induces more intense accumulation of anthropogenic metals, especially Cd, in sediment from Jabuka Pit, and the metal content slightly increases

Long-Term Trends, Variability and Extremes of In Situ Sea Surface Temperature Measured Along the Eastern Adriatic Coast and its Relationship to Hemispheric Processes

Science.gov (United States)

Grbec, Branka; Matić, Frano; Beg Paklar, Gordana; Morović, Mira; Popović, Ružica; Vilibić, Ivica

2018-02-01

This paper examines long-term series of in situ sea surface temperature (SST) data measured at nine coastal and one open sea stations along the eastern Adriatic Sea for the period 1959-2015. Monthly and yearly averages were used to document SST trends and variability, while clustering and connections to hemispheric indices were achieved by applying the Principal Component Analysis (PCA) and Self-Organizing Maps (SOM) method. Both PCA and SOM revealed the dominance of temporal changes with respect to the effects of spatial differences in SST anomalies, indicating the prevalence of hemispheric processes over local dynamics, such as bora wind spatial inhomogeneity. SST extremes were connected with blocking atmospheric patterns. A substantial warming between 1979 and 2015, in total exceeding 1 °C, was preceded by a period with a negative SST trend, implying strong multidecadal variability in the Adriatic. The strongest connection was found between yearly SST and the East Atlantic (EA) pattern, while North Atlantic Oscillation (NAO) and East Atlantic/West Russia (EAWR) patterns were found to also affect February SST values. Quantification of the Adriatic SST and their connection to hemispheric indices allow for more precise projections of future SST, considered to be rather important for Adriatic thermohaline circulation, biogeochemistry and fisheries, and sensitive to ongoing climate change.

Coding early naturalists' accounts into long-term fish community changes in the Adriatic Sea (1800-2000.

Directory of Open Access Journals (Sweden)

Tomaso Fortibuoni

Full Text Available The understanding of fish communities' changes over the past centuries has important implications for conservation policy and marine resource management. However, reconstructing these changes is difficult because information on marine communities before the second half of the 20(th century is, in most cases, anecdotal and merely qualitative. Therefore, historical qualitative records and modern quantitative data are not directly comparable, and their integration for long-term analyses is not straightforward. We developed a methodology that allows the coding of qualitative information provided by early naturalists into semi-quantitative information through an intercalibration with landing proportions. This approach allowed us to reconstruct and quantitatively analyze a 200-year-long time series of fish community structure indicators in the Northern Adriatic Sea (Mediterranean Sea. Our analysis provides evidence of long-term changes in fish community structure, including the decline of Chondrichthyes, large-sized and late-maturing species. This work highlights the importance of broadening the time-frame through which we look at marine ecosystem changes and provides a methodology to exploit, in a quantitative framework, historical qualitative sources. To the purpose, naturalists' eyewitness accounts proved to be useful for extending the analysis on fish community back in the past, well before the onset of field-based monitoring programs.

Record of an established population of Palaemon macrodactylus Rathbun, 1902 (Decapoda, Palaemonidae in the Mediterranean Sea: confirming a prediction

Directory of Open Access Journals (Sweden)

J. A. CUESTA

2014-09-01

Full Text Available The capture of larvae of Palaemon macrodactylus off Mallorca (Balearic Islands has been recently reported as evidence of a potential presence of a population of this species in the Mediterranean Sea. Photos of this species, taken during dives in the Sacca di Goro (northern Adriatic were published in the same year, but no specimen could be collected at that time. Herein we report the capture in 2013 of numerous individuals of the oriental shrimp, including ovigerous females, both in the Sacca di Goro and in the Lagoon of Marano and Grado (northern Adriatic Sea, Italy, confirming the existence of a well-established population of this species in the Mediterranean Sea.

Searching for a stock structure in Sardina pilchardus from the Adriatic and Ionian seas using a microsatellite DNA-based approach

Directory of Open Access Journals (Sweden)

Paolo Ruggeri

2013-10-01

Full Text Available In the present study the genetic variability of European sardine from Adriatic and Ionian seas was investigated in order to detect the occurrence of genetic structure within and between these basins. In several samples the analysis of genetic variability at eight microsatellite loci showed a number of homozygote individuals higher than expected at Hardy-Weinberg equilibrium. The inter-population differentiation level estimated by AMOVA, qST and rRST and Bayesian descriptors detected no signs of population differentiation between the samples analysed. These results are consistent with previous studies based on allozymes and several mitochondrial DNA markers and add further evidence contradicting the early identification, based on morphological and reproductive data, of two sub-populations in the Adriatic Sea.

Marine radioecology and waste management in the Adriatic.

Science.gov (United States)

Franić, Zdenko; Petrinec, Branko

2006-09-01

This paper gives a review of marine radioecology research in the Adriatic area carried out by the Radiation Protection Unit of the Institute for Medical Research and Occupational Health. Measurements of radioactivity in the Adriatic started in 1963 as a part of an extended monitoring programme of radioactivity in Croatian environment. The main sources of radioactive contamination of the Adriatic Sea are the fallout from past nuclear weapon testing conducted in the atmosphere and the Chernobyl accident. In 2005, the activity concentrations of fission radionuclides were detectable at very low levels in all environmental samples collected on the Adriatic. The 90Sr data obtained from long-term monitoring were used to estimate the upper limit of the Adriatic seawater turnover time, which turned out to be (3.4 +/- 0.4) years. Detailed knowledge about seawater circulation, including the turnover time is essential for planning an overall communal and other wastewater management on the Adriatic coast. The paper concludes with the prospects for future marine radioecological investigations.

Upper Cenomanian-lower Turonian sea-level rise and its consequences on the Adriatic-Dinaric carbonate platform

Science.gov (United States)

Gušić, I.; Jelaska, V.

1993-12-01

The Adriatic carbonate platform existed throughout most of the Mesozoic as an isolated (‘intraoceanic’) carbonate platform. It is characterized by what has been traditionally labelled a ‘continuous’ shallow marine carbonate sedimentation, without terrigenous influences. However, global sea-level changes left unequivocal imprints in the ‘continuous’ carbonate record, thus proving that the carbonate platform sensitively responded to sea-level fluctuations. This paper focuses on the relatively short Cenomanian — Turonian drowning event, which temporarily submerged the platform below the euphotic zone, and which is related here to the well known global Cenomanian — Turonian sea-level highstand. This drowning episode is characterized by the abrupt disappearance of numerous shallow water benthic invertebrate taxa and by an abundant occurrence of planktonic organisms, including calcispheres and ‘primitive’ planktonic foraminifera. Near the middle of the Turonian, the platform regime was re-established, correlating with the global fall in sea level. The situation is different only at the south-west margin of the platform, where pelagic sedimentation, initiated near the end of the Cenomanian, continues into the Santonian and probably marks the Adriatic trough. The drowning began earlier (in the Middle Cenomanian) in those areas nearer to the north-east margin of the platform (the area of what is today central Croatia) and then progressed gradually towards the more interior areas of the platform (the middle Dalmatian islands), which were drowned near the end of the Cenomanian.

Spatial and seasonal variability of fractionated phytoplankton biomass and primary production in the frontal region of the Northern Adriatic Sea

Directory of Open Access Journals (Sweden)

M.R. VADRUCCI

2005-06-01

Full Text Available Spatial and seasonal patterns of variation of fractionated phytoplankton biomass and primary production and their relationships with nutrient concentrations were analyzed along an inshore - offshore gradient and in relation to the presence of a frontal system in the Northern Adriatic Sea. Sampling was carried out in winter and summer during four oceanographic cruises (June 1996 and 1997, February 1997 and 1998 as part of the PRISMA II project. Water samples for determining nutrient concentrations, phytoplankton biomass (as Chla and primary production (as 14 C assimilation were collected at five optical depths. Sampling stations were located along 2 or 4 parallel transects arranged perpendicularly to the shoreline and the frontal system. The transects were located at such a distance from the coast that the frontal system crossed them at their halfway point. Total dissolved nitrogen (TDN and total dissolved phosphorus concentrations (TDP were 12.41 ± 3 .95 mM and 0.146 ± 0 .070 mM, respectively. The values in the two seasonal periods were similar, decreasing along the inshore-offshore gradient. Values for phytoplankton biomass and primary productionwere higher in the winter than the summer cruises, and decreased, in both seasonal periods, along the inshore / offshore gradient. Moreover, in both seasonal periods, picophytoplankton dominated both biomass and productivity, (56% and 44%, respectively at stations beyond the frontal system, while microphytoplankton was more important at stations inside it (44% and 44%, respectively. Total phytoplankton biomass and primary production were directly related to nutrient concentrations. Regarding size classes, significant patterns of variation with nutrients were observed particularly for biomass. The results indicate that the size structure and function of phytoplankton guilds seem to be mediated by nutrient inflow, as well as by competitive interaction among size fractions.

Levels of total mercury in marine organisms from Adriatic Sea, Italy.

Science.gov (United States)

Perugini, Monia; Visciano, Pierina; Manera, Maurizio; Zaccaroni, Annalisa; Olivieri, Vincenzo; Amorena, Michele

2009-08-01

The presence of total mercury in fish, crustacean and cephalopod from Adriatic Sea, was investigated. The highest concentrations were observed in decreasing order in: Norway lobster (0.97 +/- 0.24 mg/kg; mean +/- SE), European hake (0.59 +/- 0.14 mg/kg), red mullet (0.48 +/- 0.09 mg/kg), blue whiting (0.38 +/- 0.09 mg/kg), Atlantic mackerel (0.36 +/- 0.08 mg/kg) and European flying squid (0.25 +/- 0.03 mg/kg). A significant difference (p fish and fishery products can exceed the maximum levels and stress the need of more information for consumers in particular for people that eat large amount of fish.

Mercury in the sediments of the Marano and Grado Lagoon (northern Adriatic Sea): Sources, distribution and speciation

Science.gov (United States)

Acquavita, Alessandro; Covelli, Stefano; Emili, Andrea; Berto, Daniela; Faganeli, Jadran; Giani, Michele; Horvat, Milena; Koron, Neža; Rampazzo, Federico

2012-11-01

The existence of mining tailings in Idrija (Slovenia) and their subsequent transportation via the Isonzo River has been the primary source of mercury (Hg) in the northern Adriatic Sea for almost 500 years, making the Gulf of Trieste and the adjacent Marano and Grado Lagoon two of the most contaminated marine areas in the world. A further, more recent, contribution of Hg has been added by the operation of a chlor-alkali plant (CAP) located in the drainage basin flowing into the Lagoon. On the basis of previous research, as well as new data obtained from the "MIRACLE" project (Mercury Interdisciplinary Research for Appropriate Clam farming in a Lagoon Environment), the spatial distribution of Hg and its relationships with methylmercury (MeHg), organic matter and several geochemical parameters in surface sediments were investigated. The predominant and long-term impacts of the cinnabar-rich Isonzo River particulate matter in the Lagoon surface sediments are evident and confirmed by a decreasing concentration gradient from east (>11 μg g-1) to west (0.7 μg g-1). Hg originated from the CAP is only significant in the central sector of the Lagoon. Hg is primarily associated with fine-grained sediments (constitutes, on average, 0.08% of total Hg and percentages are comparable to those obtained in similar lagoon environments. Higher MeHg concentrations in low to intermediate Hg-contaminated sediments indicate that the metal availability is not a limiting factor for MeHg occurrence, thus suggesting a major role played by environmental conditions and/or speciation. The reasonably good correlation between MeHg normalized to humic acid (HA) content and humic δ13C indicates that MeHg is preferentially associated with autochthonous δ13C-enriched HAs in lagoon surface sediments, suggesting that the structure of "marine" HAs, less refractory and less aromatic, could favor MeHg binding and/or production. In the context of the potential hazard of Hg and MeHg accumulation in

On the fecundity of the Black Sea bream, Spondyliosoma cantharus (L. , from the Adriatic Sea (Croatian coast

Directory of Open Access Journals (Sweden)

Jakov Dulcic

1998-09-01

Full Text Available The fecundity of the Black Sea bream from the eastern middle Adriatic (Croatian coast was assessed by the volumetric method using 59 ovaries in pre-spawning stage from fish between 18.5 and 33.5 cm total length. Estimates of total potential annual fecundity varied between 31,670 and 554,070 eggs per female. Relationships between total potential fecundity and total length (TL, total weight (TW and age (A were established using the multiplicative regression model. Relative fecundity is constant, reaching a maximum of 850 eggs per g in the 30.5 cm to 31.0 cm length class.

An Empirical Ocean Colour Algorithm for Estimating the Contribution of Coloured Dissolved Organic Matter in North-Central Western Adriatic Sea

Directory of Open Access Journals (Sweden)

Alessandra Campanelli

2017-02-01

Full Text Available The performance of empirical band ratio models were evaluated for the estimation of Coloured Dissolved Organic Matter (CDOM using MODIS ocean colour sensor images and data collected on the North-Central Western Adriatic Sea (Mediterranean Sea. Relationships between in situ measurements (2013–2016 of CDOM absorption coefficients at 355 nm (aCDOM355 with several MODIS satellite band ratios were evaluated on a test data set. The prediction capability of the different linear models was assessed on a validation data set. Based on some statistical diagnostic parameters (R2, APD and RMSE, the best MODIS band ratio performance in retrieving CDOM was obtained by a simple linear model of the transformed dependent variable using the remote sensing reflectance band ratio Rrs(667/Rrs(488 as the only independent variable. The best-retrieved CDOM algorithm provides very good results for the complex coastal area along the North-Central Western Adriatic Sea where the Po River outflow is the main driving force in CDOM and nutrient circulation, which in winter mostly remains confined to a coastal boundary layer, whereas in summer it spreads to the open sea as well.

Plastic debris in the Mediterranean Sea: Types, occurrence and distribution along Adriatic shorelines.

Science.gov (United States)

Munari, Cristina; Scoponi, Marco; Mistri, Michele

2017-09-01

Small plastic debris in sediments from five beaches were investigated to evaluate their occurrence and abundance in the Northern Adriatic coast for the first time. Plastic debris extracted from sediments were counted, weighted and identified by Fourier-transform infrared spectroscopy (FT-IR). A total of 1345 items of debris (13.491g) were recorded, with a mean density of 12.1 items kg -1 d.w. and 0.12gkg -1 d.w. Fragments were the most frequent type of small plastics debris detected. In terms of abundance, microplastics (emergent and priority contaminant. Copyright © 2017 Elsevier Ltd. All rights reserved.

Spatial distribution of microphytobenthos, meiofauna and macrofauna in the north-western Adriatic Sea: a synoptic study

Directory of Open Access Journals (Sweden)

Annalisa Franzo

2015-12-01

Full Text Available In view of the general paucity of integrated information on offshore benthic communities in the Adriatic Sea and given the vulnerability of this particular coastal system, microphytobenthos, meiofauna and macrofauna were synoptically investigated in front of the Emilia-Romagna coast (northern Adriatic Sea in September 2010 and March 2011. As required by the Marine Strategy Framework Directive, which extends its action beyond the territorial waters (within 12 nmi of the Member States, our findings could help to fill the gap of knowledge on the environmental status in offshore areas since the study was carried out also at >12 nmi from the coastline. In fact, sediment samples for the analysis of the benthic communities were collected from a 10-point-station grid that covered an area of about 400 km2 with water depths ranging from 13 to 50 m. The variability of the sediment grain size and other chemical variables in the sediment suggests the presence of two distinct environmental contexts that enhance the proliferation of different benthic communities. At the inshore stations (depth <20 m the higher sand percentages and the maxima of dissolved inorganic nitrogen concentrations indicate the presence of hydrodynamic perturbations and the influence of nutrient loads of terrestrial origin. Inshore, both meio- and macrofaunal communities were poorly structured and dominated by relatively more opportunistic taxa, such as nematodes and the bivalve Corbula gibba. Offshore stations (depth >20 m had muddier sediments, which likely exerted a greater retention of sediment-bound organic matter. These conditions seemed to favour benthic deposit feeders like meio- and macrofaunal annelids. Surprisingly, a conspicuous microphytobenthic community, mainly represented by the diatom Paralia sulcata, has been observed even at remarkable depths (~50 m opening new questions regarding the role of these organisms in dim-light conditions. Although the investigated benthic

Effect of salinity on metal mobility in Sečovlje salina sediment (northern Adriatic, Slovenia)

Science.gov (United States)

Kovač, N.; Ramšak, T.; Glavaš, N.; Dolenec, M.; Rogan Šmuc, N.

2016-12-01

Saline sediment (saline healing mud or "fango") from the Sečovlje Salina (northern Adriatic, Slovenia) is traditionally used in the coastal health resorts as a virgin material for medical treatment, wellness and relax purposes. Therapeutic qualities of the healing mud depend on its mineralogical composition and physical, mineralogical, geochemical and biological properties. Their microbial and potentially toxic elements contamination are the most important features affecting user safety. However, the degree of metal toxicity (and its regulation) for natural healing mud is still under discussion. Therefore, the influence of the overlying water salinity on the mobility of heavy metals (and some other geochemical characteristic) was studied for saline sediments of the Sečovlje Salina. Experiments takes place in tanks under defined conditions i.e. at day (21 °C): night (16 °C) cycle for three months. Sediment was covered with water of different salinities (36, 155, 323 g NaCl L-1 and distillate water) and mixed/stirred every week during the experimental period. At the same time, the evaporated water was replaced with distilled water. The mud samples were analyzed, at the beginning and at the end of experiment, for mineral (XRD), elemental composition (ICP-MS) and organic content (% TOC, % TN). Geochemical analysis of the aqueous phase (content of cations and anions) have also been carried out in an accredited Canadian laboratory Actlabs (Activation Laboratories, Canada). Salinity and maturation of sediment does not significantly affect its mineral composition. The samples taken at the end of the experiment have higher percent of water but lower organic carbon concentration. Concentrations of investigated elements are comparable to that in surface sediments from Central Adriatic Sea. In the water phase, concentrations of most elements (As, Ba, Cu, Mo, Mn, Ni, Sr, Sb) rise from the beginning to the end of the experiment, whereas the metal (potentially toxic elements

Sources of CO{sub 2} in the Gulf of Trieste (N. Adriatic). Stable Carbon Isotope Evidence

Energy Technology Data Exchange (ETDEWEB)

Ogrinc, N.; Zavadlav, S. [Department of Environmental Sciences, Jozef Stefan Institute, Ljubljana (Slovenia); Turk, D. [Department of Oceanography, Dalhousie University, Halifax, Nova Scotia (Canada); Lamont-Doherty Earth Observatory, Earth Institute at Columbia University, Palisades, NY (United States); Faganeli, J. [Marine Biological Station National Institute of Biology, Piran (Slovenia)

2013-07-15

In the present study the influence of freshwater intrusions on the net carbon dynamics in the Gulf of Trieste (northern Adriatic Sea) were investigated. Carbonate mineral weathering dominates the inorganic carbon geochemical flux of the N Adriatic rivers and thus the origin of dissolved inorganic carbon (DIC) in the gulf seawater. Based on {delta}{sup 13}C{sub DIC} values and isotopic mass balance it was estimated that rivers represents about 20% of DIC in spring, while the riverine contribution in autumn is less pronounced probably due to intensive water mixing. The results, therefore, suggest that river inputs play a significant role in the carbon cycling in the Gulf of Trieste due to mixing of higher DIC riverine water with lower seawater DIC. The observed higher summer {delta}{sup 13}C{sub DIC} values were due to more pronounced photosynthetic carbon fractionation. (author)

Investigation on tsunami effects in the central Adriatic Sea during the last century – a contribution

Directory of Open Access Journals (Sweden)

A. Maramai

2007-01-01

Full Text Available In this work we present the result of a study aimed at examining the Italian earthquake sequences that occurred in the area of the central Adriatic sea with the purpose of understanding whether some of them were accompanied by tsunami effects. The motivation for this research was the update and enrichment of the Italian Tsunami Catalogue. The result was that evidence was found for two new cases of earthquake-induced tsunamis: these are the August 1916 Rimini and the October 1930 Ancona events. The bulk of the present research consisted in collecting all the available data on the earthquakes that affected the selected area in the past century and in identifying those potentially capable of generating tsunamis. During the study all the available material was gathered, which includes specific monographs and scientific papers, articles available in contemporary chronicles and in local and national newspapers. The final result of this research will improve our knowledge of the tsunamigenic activity of the central Adriatic sea and contribute to the assessment of the tsunami hazard and risk along these coasts, that especially in the peak season form one of the most densely populated areas of the Italian peninsula with flat and large beaches and water front resorts crowded of tourists.

PH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using Alkalinity titrator, CTD and other instruments from PROFESSOR SIEDLECKI in the Adriatic Sea, Aegean Sea and others from 1988-11-17 to 1988-11-26 (NCEI Accession 0144306)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144306 includes discrete sample and profile data collected from PROFESSOR SIEDLECKI in the Adriatic Sea, Aegean Sea, Mediterranean Sea, Mediterranean...

Hg, Pb and Cd in zooplankton from an area of the Adriatic opposite the Romagna coast line

Energy Technology Data Exchange (ETDEWEB)

Crisetig, G; Cattani, O; Massa, D; Poletti, R

1982-09-15

The concentrations of heavy metals Hg, Pb and Cd found in zooplankton samples collected in two stations off Cesenatico (Northern Adriatic Sea) from March 1978 to January 1979, have been reported. The Hg, Pb and Cd concentrations showed large variations which did not seem to be correlated with taxonomic composition. The detected levels of metals were higher at the offshore than the nearshore station, accordingly with the sediment pattern. The high concentration of Hg were apparently associated with sources of local industrial pollution.

Picoplankton distribution influenced by thermohaline circulation in the southern Adriatic

Science.gov (United States)

Šilović, Tina; Mihanović, Hrvoje; Batistić, Mirna; Radić, Iris Dupčić; Hrustić, Enis; Najdek, Mirjana

2018-03-01

In this study, we focus on the interactive dynamics between physico-chemical processes and picoplankton distribution in order to advance our current understanding of the roles of various parameters in regulating picoplankton community structure in highly dynamic marine system such as the South Adriatic Sea. The research was carried out between October 2011 and September 2012 along the transect in the northern part of the South Adriatic Pit. The deep water convection occurred in the southern Adriatic during February 2012, with vertical mixing reaching the depth of 500 m. The picoplankton community was highly affected by this mixing event, whilst its compartments each responded differently. During deep water convection low nucleic acid heterotrophic bacteria (LNA HB) and Synechococcus had their lowest abundances (4 × 105 cell ml-1 and 8 × 102 cell ml-1, respectively), picoeucaryotes had their highest abundances (104 cell ml-1), while Prochlorococcus was absent from the area, most likely due to intense cooling and vertical mixing. In March 2012 Eastern Adriatic Current (EAC) brought warm and saline water with more nutrients, which resulted in the proliferation of high nucleic acid heterotrophic bacteria (HNA HB), having maximal abundance (4 × 105 cell ml-1). The re-establishment of Levantine Intermediate Water (LIW) intrusion after the deep water convection resulted in the re-appearance of Prochlorococcus and maximal abundances of Synechococcus (4 × 104 cell ml-1) in May 2012. The distribution of picoheterotrophs was mainly explained by the season, while the distribution of picophytoplankton was explained by the depth. Aside from nutrients, salinity was an important parameter, affecting particularly Prochlorococcus. The re-appearance of Prochlorococcus in the southern Adriatic during the period of LIW intrusion, together with their correlation with salinity, indicates their potential association with LIW. The relationship between Prochloroccocus distribution and

Regional approach to modeling the transport of floating plastic debris in the Adriatic Sea.

Science.gov (United States)

Liubartseva, S; Coppini, G; Lecci, R; Creti, S

2016-02-15

Sea surface concentrations of plastics and their fluxes onto coastlines are simulated over 2009-2015. Calculations incorporate combinations of terrestrial and maritime litter inputs, the Lagrangian model MEDSLIK-II forced by AFS ocean current simulations, and ECMWF wind analyses. With a relatively short particle half-life of 43.7 days, the Adriatic Sea is defined as a highly dissipative basin where the shoreline is, by construction, the main sink of floating debris. Our model results show that the coastline of the Po Delta receives a plastic flux of approximately 70 kg(km day)(-1). The most polluted sea surface area (>10 g km(-2) floating debris) is represented by an elongated band shifted to the Italian coastline and narrowed from northwest to southeast. Evident seasonality is found in the calculated plastic concentration fields and the coastline fluxes. Complex source-receptor relationships among the basin's subregions are quantified in impact matrices. Copyright © 2015 Elsevier Ltd. All rights reserved.

Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using Alkalinity titrator, CTD and other instruments from METEOR in the Adriatic Sea, Aegean Sea and others from 2011-04-05 to 2011-04-28 (NODC Accession 0108079)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0108079 includes discrete sample and profile data collected from METEOR in the Adriatic Sea, Aegean Sea, Alboran Sea, Ionian Sea, Mediterranean Sea,...

An Empirical Ocean Colour Algorithm for Estimating the Contribution of Coloured Dissolved Organic Matter in North-Central Western Adriatic Sea

OpenAIRE

Alessandra Campanelli; Simone Pascucci; Mattia Betti; Federica Grilli; Mauro Marini; Stefano Pignatti; Stefano Guicciardi

2017-01-01

The performance of empirical band ratio models were evaluated for the estimation of Coloured Dissolved Organic Matter (CDOM) using MODIS ocean colour sensor images and data collected on the North-Central Western Adriatic Sea (Mediterranean Sea). Relationships between in situ measurements (2013–2016) of CDOM absorption coefficients at 355 nm (aCDOM355) with several MODIS satellite band ratios were evaluated on a test data set. The prediction capability of the different linear models was assess...

137Cs and 40K activity in individuals of the mullet (Mugilidae) species Liza aurata from the South Adriatic sea

International Nuclear Information System (INIS)

Antovic, I.; Antovic, N. M.

2009-01-01

The results of the 137 Cs i 40 K activity measurements in whole individuals and some organs of the mullet species Liza aurata from the South Adriatic Sea, are presented. The measurements were performed in the non-coincidence mode of counting of the multidetector spectrometer PRIPYAT-2M. (author) [sr

Internal Tidal Hydrodynamics and Ambient Characteristics of the Adriatic (ITHACA)

Science.gov (United States)

2006-12-31

document atmospheric conditions along the line extending from the coast to the open sea. 2.1. Measuring sites Position of meteorological measuring sites...idealized case, they are perpendicular to the straight shoreline. However, along the eastern Adriatic irregularly shaped coast there is a number of...Cvitan, 2003; Belusic et al., 2004; Belusic and Klaic, 2004, 2006), southwestward, downslope windstorm , which frequently blows over the Adriatic

Delta-associated molluscan life and death assemblages in the northern Adriatic Sea: Implications for paleoecology, regional diversity and conservation.

Science.gov (United States)

Weber, Kristina; Zuschin, Martin

2013-01-15

Life-death (LD) studies of shelly macrofauna are important to evaluate how well a fossil assemblage can reflect the original living community, but can also serve as a proxy for recent ecological shifts in marine habitats and in practice this has to be distinguished using taphonomic preservation pattern and estimates of time-averaging. It remains to be rigorously evaluated, however, how to distinguish between sources of LD disagreement. In addition, death assemblages (DAs) also preserve important information on regional diversity which is not available from single censuses of the life assemblages (LAs). The northern Adriatic Sea is an ecosystem under anthropogenic pressure, and we studied the distribution and abundance of living and dead bivalve and gastropod species in the physically stressful environments (tidal flat and shallow sublittoral soft bottoms) associated with the delta of the Isonzo River (Gulf of Trieste). Specifically we evaluated the fidelity of richness, evenness, abundance, habitat discrimination and beta diversity. A total of 10,740 molluscs from fifteen tidal flat and fourteen sublittoral sites were analyzed for species composition and distribution of living and dead molluscs. Of 78 recorded species, only eleven were numerically abundant. There were many more dead than living individuals and rarefied species richness in the DA was higher at all spatial scales, but the differences are lower in habitats and in the region than at individual stations. Evenness was always higher in death assemblages, and probably due to temporally more variable LAs the differences are stronger in the sublittoral habitats. Distinct assemblages characterized intertidal and sublittoral habitats, and the distribution and abundance of empty shells generally corresponded to that of the living species. Death assemblages have lower beta diversity than life assemblages, but empty shells capture compositional differences between habitats to a higher degree than living shells

Imposex levels and butyltin compounds (BTs) in Hexaplex trunculus (Linnaeus, 1758) from the northern Adriatic Sea (Italy): Ecological risk assessment before and after the ban.

Science.gov (United States)

Cacciatore, Federica; Boscolo Brusà, Rossella; Noventa, Seta; Antonini, Camilla; Moschino, Vanessa; Formalewicz, Malgorzata; Gion, Claudia; Berto, Daniela; Gabellini, Massimo; Marin, Maria Gabriella

2018-01-01

The aim of this study was to compare imposex and butyltin compounds (BTs) data, collected before and after the organotin ban in 2008, in order to assess temporal and spatial variation of the phenomenon, the decline of BT contamination, and the effects on Hexaplex trunculus population in the coastal area of the northern Adriatic Sea, close to the Venice Lagoon. Both in marine and in lagoon sites, the results obtained in 2013-2015 showed a significant decline in the incidence of imposex in respect to those from the 2002 survey. In 2002, lagoon samples exhibited Relative Penis Size Index (RPSI) higher than marine samples, whereas no differences were detected in the recent survey, when all RPSI values were below 0.6%. Vas Deference Sequence Index (VDSI) mean values were over 4 before the ban introduction and below this value after that, indicating more critical conditions for gastropod population in 2002 rather than in 2013-15. Percentage of sterile females was up to 69% in 2002, whilst in the more recent survey no sterile female was found. Range of BT concentrations in gastropods decreased from 252 to 579 to 16-31ng∑BT/g d.w. BT body burdens varied according to a gender dependant pattern, with higher concentrations observed in females than in males. A first attempt to propose a classification based on BT impact on H. trunculus, according to the Water Framework Directive, revealed that most sites were in Bad ecological status before the ban and attained a Poor/Moderate status after that. Copyright © 2017 Elsevier Inc. All rights reserved.

Studies on phycobiliproteins in Algae. VI. Light-harvesting phycobiliprotein pigments in some Rhodophyta from the Adriatic Sea

Directory of Open Access Journals (Sweden)

Bazyli Czeczuga

2014-01-01

Full Text Available The phycobiliprotein content in 5 species of red algae from the coast of the Adriatic Sea' was studied by chromatography on Sephadex G-100. The phycobiliproteins, R-phycoerythrin, C-phycocyanin and allophycocyanin were identified. The total content of phycobiliproteins ranged from 0.152 (Phyllophora nervosa to 1.874 mg•g-1 dry wt. (Plocamium cartilagineum. The dominant phycobiliproteins were found to belong to the phycocyanin group, this resulting from complementary chromatic adaptation.

Turbidity, SOLAR RADIATION - ATMOSPHERIC and other data from UNKNOWN in the Adriatic Sea from 1948-03-19 to 1991-11-16 (NODC Accession 9800082)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Temperature, salinity, nutrients, and other data were collected from CTD and bottle casts in the Adriatic Sea from 19 March 1948 to 16 November 1991. Data include...

Changes in the Adriatic oceanographic properties induced by the Eastern Mediterranean Transient

Directory of Open Access Journals (Sweden)

I. Vilibić

2012-06-01

Full Text Available Long-term time series of physical and chemical parameters collected between 1960 and 2010 along the Palagruža Sill transect, Middle Adriatic Sea, have been investigated in terms of average water properties and their variability. Nutrients, especially orthophosphates, reached rather high levels of concentration below the euphotic zone between 1991 and 1998, the highest levels in the investigated period. Simultaneously, the N:P ratio, which is normally higher than 25:1, decreased to values less than 16:1 in the euphotic zone, indicating a switch from typical phosphorus to nitrogen- limited preconditioning for the primary production. Higher-than-usual nutrient levels peaking in the mid-1990s, coupled with lower-than-usual temperature, salinity, dissolved oxygen and pH values, are presumably related to the flow of the nutrient richer Western Mediterranean waters to the Adriatic below the euphotic layer. These waters, which keep their footprint in the N:P ratio, enter the Adriatic during the anticyclonic phase of the Bimodal Adriatic-Ionian Oscillation (BiOS, which has been uniquely strengthened by the Eastern Mediterranean Transient occurring in the early 1990s. This hypothesis should be confirmed through targeted research and modelling exercises, as it is highly relevant for the biogeochemistry of the Adriatic Sea.

Partial pressure (or fugacity) of carbon dioxide and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer and other instruments from POLARSTERN in the Adriatic Sea, Aegean Sea and others from 2014-03-09 to 2015-01-31 (NCEI Accession 0160489)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0160489 includes Surface underway, chemical and meteorological data collected from POLARSTERN in the Adriatic Sea, Aegean Sea, Alboran Sea, Arabian...

New data on Eimeria dicentrarchi (Apicomplexa: Eimeriidae), a common parasite of farmed European sea bass (Dicentrarchus labrax) from the mid-eastern Adriatic

Science.gov (United States)

This study extends the original description of Eimeria dicentrarchi Daoudi and Marquès, 1987, a common coccidian parasite of European sea bass from the mid-eastern Adriatic, by providing insights into the parasite’s site of infection, development and pathogenicity. E. dicentrarchi was found in vario...

Dissolved inorganic carbon, alkalinity, temperature, salinity and OXYGEN - APPARENT UTILIZATION (AOU) collected from discrete sample and profile observations using CTD, bottle and other instruments from UNKNOWN PLATFORMS in the Adriatic Sea, Aegean Sea and others from 1874-10-11 to 2000-04-26 (NODC Accession 0117350)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0117350 includes chemical, discrete sample, physical and profile data collected from UNKNOWN PLATFORMS in the Adriatic Sea, Aegean Sea, Alboran Sea,...

Distribution and morphological abnormalities of recent foraminifera in the Marano and Grado Lagoon (North Adriatic Sea, Italy

Directory of Open Access Journals (Sweden)

R. MELIS

2013-10-01

Full Text Available The Marano and Grado Lagoon, is a northern Adriatic wetland system of relevant naturalistic and economic value, that is constantly under quality control in accordance with the current environmental directives. Benthic foraminifers community with its morphological abnormalities were investigated in the recent sediments (about 10 years old of 21 stations collected in the framework of the “MIRACLE” Project which aimed at testing the coexistence of clam farming with high Hg contamination. Euryhaline foraminifers, well known in Mediterranean brackish-waters, mainly characterizes the total assemblage. A. tepida dominates in areas characterized by low salinity, high clay and Corg content, but also to anthropogenic pressure. E. gunteri and H. germanica are recorded in the western sector of the lagoon, which is more affected by salinity variations and agricultural activities. Slightly higher values of assemblage diversity appear in less restricted areas of the lagoon or, at least, where physical parameters such as temperature and salinity are less variable. The test abnormalities, carried out on total assemblage, shows that the FAI (Foraminiferal Abnormality Index values always exceed 1% of the total assemblage, with clear decreasing gradients from inland to the sea (from N to S and from W to E in the studied area.

Characteristic carotenoids in some phytobenthos species in the coastal area of the Adriatic Sea

Directory of Open Access Journals (Sweden)

Bazyli Czeczuga

2014-01-01

Full Text Available The author investigated the presence of various carotcnoids in some phytobenthos species (20 species representative of Chlorophytn, Phaeophyta and Rhodophyta from the coast of the Adriatic Sea. The presence of following carotenoids has been determined 1 in Chlorophyta lycopene, α-, β-, γ- , ε-carotene, β-cryptoxanthin, lutein, lutein epoxide, zeaxanthin, antheraxanthin, neoxanthin, violaxanthin, siphonein and astaxanthin esier; 2 in Phorophyta: α-, β-, γ- , ε- carotene, zeaxanthin, antheraxanthin, diataxanthin, fucoxanthin, fucoxanthol, neoxanthin, violaxanthin and rhodoxanthin-like: 3 in Rhodophyta α-, β-, γ-carotene,α-, β-,cryptoxanthin, lutein lutein epoxide, zeaxanthin, anthcraxanthin, mutatoxanthin, fucoxanthin neoxanthin and violaxanthin The total carotenoid content ranged from 1.197 ( Cystoseira corniculata to 16 748 mg g-1 dry weight (Chaetomorpha aerea.

PHYTOPLANKTON COMPOSITION IN FISH FARMS ALONG THE EASTERN ADRIATIC COAST

Directory of Open Access Journals (Sweden)

Marija Tomec

2006-10-01

Full Text Available Investigations of net phytoplankton composition were performed at three fish farms situated at the northern, middle and southern part of the eastern Adriatic Sea coast, respectively. In the northern part investigations were conducted in the Limski kanal, in the middle part at the Ugljan island and in the southern part in the place Drače on the Pelješac peninsula (Figure 1. At all three localities fish culture included mostly two species: gilthead sea bream (Sparus aurata and sea bass (Dicentrarchus labrax. Beside some physico–chemical parameters (sea water temperature, salinity special attention was placed on the examination of qualitative net phytoplankton composition, which was conducted in the period of May and November 2004 and May and October 2005. Samples were collected at the depths of 0. 5 and 4 meters. According to the physico–chemical parameters, sea water temperature was influenced by the temperature of the environment. Qualitative net phytoplankton composition consisted of 153 microphytic species belonging to the systematic compartments of Cyanobacteria, Chrysophyta and Dinophyta (Table 1. The most numerous algal group were diatoms or Bacillarophyceae (84 species or 55% with relative frequencies of species from 1 to 7. Taxonomic composition of diatoms showed the community Chaetoceros–Rhizosolenia (Proboscia as the dominant one. The second numerically most dominant compartment were Dinophyta (62 species or 401% with dominant the species of the genera Ceratium and Protoperidinium. Relative frequencies of species was ranging from 1 to 7 (mass presence of specimens in the water column. From Cyanobacteria (4 species or 3%, only filamentous algae were determined, with individual presence in net phytoplankton composition. Qualitative net phytoplankton composition suggests the similarity of species composition in the water column at all investigated fish farms. From the obtained characteristics of net phytoplankton composition

Comparison of growth rates estimated by otolith reading of Scorpaena porcus and Scorpaena notata caught on artificial and natural reefs of the northern Adriatic sea

Directory of Open Access Journals (Sweden)

Giuseppe Scarcella

2011-01-01

Full Text Available Despite the high number of studies on fish assemblages associated with artificial reefs and offshore platforms, little information exists on the growth rates of fish living on artificial and natural substrates. Age and growth was determined throughout otolith reading on two commercial scorpionfishes (Scorpaena porcus and Scorpaena notata caught in the surroundings of artificial structures (artificial reefs and gas platforms and natural habitats. Von Bertalanffy growth parameters were calculated for each species separately for each site. Age of S. porcus and S. notata ranged from 0 to 8 years and from 0 to 16 years, respectively. Kimura test applied to Von Bertalanffy growth curves indicated that the individuals of both species inhabiting the artificial structures had higher growth parameters than those caught in the natural habitat. The presence of artificial habitats in the northern Adriatic Sea positively affects growth rates and growth performance of both species, likely for the greater prey availability in respect to the natural open sea.Apesar do elevado número de estudos sobre as assembléias de peixes associadas a recifes artificiais e plataformas offshore, existe pouca informação sobre as taxas de crescimento dos peixes que vivem em substratos artificiais e naturais. A idade e crescimento foram determinados pela leitura de otólitos em dois peixes escorpião comerciais (Scorpaena porcus e Scorpaena notata capturados nas imediações de estruturas artificiais (recifes artificiais e plataformas de gás e habitats naturais. Parâmetros de crescimento de von Bertalanffy foram calculadoss separadamente para cada espécie e cada local. A idade de Scorpaena porcus e Scorpaena notata variou entre 0 e 8 anos e 0 e 16 anos, respectivamente. O teste Kimura aplicado às curvas de crescimento de Bertalanffy indicaram que os indivíduos das duas espécies que habitam as estruturas artificiais tinham parâmetros de crescimento mais elevados do que

Sources, Fate and Distribution of Organic Matter on the Western Adriatic Continental Shelf, Italy

International Nuclear Information System (INIS)

Tesi, Tommaso; Miserocchi, Stefano; Langone, Leonardo; Boni, Laurita; Guerrini, Franca

2006-01-01

In the framework of the EUROSTRATAFORM projects, a multidisciplinary research was focused on processes that involve transport and deposition of riverine material in the Adriatic Sea. The aim of our contribution was to increase a more complete understanding of organic matter deposition on the Adriatic shelf, also taking into account the role of Apennine rivers beyond the Po influence. In order to characterize origin, fate and variability of sedimentary organic carbon we utilized elemental and stable carbon isotope data in surficial sediments along shallow cross-shelf transects on the western Adriatic shelf

Messinian post-evaporitic paleogeography of the Po Plain-Adriatic region by 3D numerical modeling: implications for the Central Mediterranean desiccation during the MSC

Science.gov (United States)

Amadori, Chiara; Garcia-Castellanos, Daniel; Di Giulio, Andrea; Fantoni, Roberto; Ghielmi, Manlio; Sternai, Pietro; Toscani, Giovanni

2017-04-01

In the last decades the Messinian Salinity Crisis (MSC) has been the topic of a number of studies, in particular in onshore areas, as they offer a unique opportunity to analyze the controlling factors and the geological consequences of the estimated 1.5 km sea-level drop. During the MSC, the geometry of western and eastern sides of the Mediterranean basin was similar to the present day basin while, important changes took place in the central portion as a consequence of the (still ongoing) tectonic activity of the Apennine domain. Recent high-resolution 2D seismo-stratigraphic and 1D backstripping analysis by Eni E&P group described a step-wise sea-level lowering during evaporitic and post-evaporitic MSC phases in the Po Plain-Northern Adriatic foreland (PPAF), with a sea-level drop not exceeding 900 m. Thanks to a dense grid of 2D seismic profiles, integrated with ca. 200 well logs (confidential data, courtesy of ENI E&P), a 3D reconstruction of the entire northern PPAF basin geometry and the facies distribution during the Latest Messinian time has been carried out. In this study, we performed a 3D backstripping and lithospheric scale uplift calculations of the northern PPAF basin testing the 800-900m of sea-level draw down. The resulted restored Latest Messinian paleotopography (corresponding to the bottom Pliocene in the most of the study area) and related shoreline position, strongly fit with the recentmost continental/marine facies distribution maps. The latest Messinian morphology shows deep marine basins persisting during the entire MSC period, filled by clastic turbiditic sediments and a wide emerged area along the Southern Alps margin and Friulian-Venetian basin. A 3D reconstruction of the Latest Messinian surface shows peculiar river incisions along the Southern Alps margin; these V-shape canyons perfectly fit with the present day fluvial network, dating back the drainage origin at least at the Messinian acme. Moreover, if in a well-constrained marginal

Partial pressure (or fugacity) of carbon dioxide, temperature, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer and other instruments from unknown platforms in the Adriatic Sea, Aegean Sea and others from 2012-01-01 to 2012-12-31 (NODC Accession 0059946)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0059946 includes Surface underway, chemical, meteorological and physical data collected from unknown platforms in the Adriatic Sea, Aegean Sea,...

Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer and other instruments from Celebrity Equinox in the Adriatic Sea, Aegean Sea and others from 2016-01-02 to 2017-01-02 (NCEI Accession 0157264)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0157264 includes Surface underway, chemical, meteorological and physical data collected from Celebrity Equinox in the Adriatic Sea, Aegean Sea,...

Mortality of red mullet (Mullus barbatus Linnaeus, 1758 on the Montenegrin shelf (South Adriatic

Directory of Open Access Journals (Sweden)

Joksimović A.

2009-01-01

Full Text Available Red mullet, Mullus barbatus Linnaeus, 1758, is an economically very important species in trawl fisheries in the Adriatic Sea. Material for analysis was collected from October 2002 until May 2004 with a bottom trawl net from commercial trawlers on the Montenegrin shelf. Mortality of this species was analyzed for the first time in this area, sepa­rately for males and females and for both sexes together. Until now, only the spatial distribution and catch per unit of effort (CPUE of Mullus barbatus have been studied in Montenegrin waters. Estimated total mortality rates were Zmales = 0.653 and Zfemales = 0.712. The average mortality rate for both sexes was Z m+f = 0.749, while the natural mortality rate was Mm+f = 0.342. Values of Z in the Montenegrin shelf area are considerably lower than Z values for the Croatian and Italian parts of the Adriatic Sea, indicating that on the Montenegrin shelf fishing of this species is significantly less intensive than in other trawl-fishing areas of the Adriatic Sea.

Environmental control of asexual reproduction and somatic growth of Aurelia spp. (Cnidaria, Scyphozoa) polyps from the Adriatic Sea

OpenAIRE

Hubot, Nathan; Lucas, Cathy H.; Piraino, Stefano

2017-01-01

Polyps of two moon jellyfish species, Aurelia coerulea and A.relicta, from two Adriatic Sea coastal habitats were incubated under multiple combinations of temperature (14, 21 °C), salinity (24, 37 ppt) and food regime (9.3, 18.6, 27.9 μg C ind‾¹ week‾¹) to comparatively assess how these factors may influence major asexual reproduction processes in the two species. Both species exhibited a shared pattern of budding mode (Directly Budded Polyps: DBP; Stolonal Budded Polyps: SBP), with DBP favo...

Population dynamics of toxic phytoplankton and bacterial flora in the waters of the low Adriatic sea; Dinamica di popolazione di fitoplancton tossico e flora batterica nel basso Adriatico

Energy Technology Data Exchange (ETDEWEB)

Caroppo, C.; Stabili, L.; Cavallo, R.A.; Pastore, M. [CNR, Ist. Sperimentale Talassografico Attlio Cerruti, Taranto (Italy); Marchiori, E. [Rome Univ., Rome (Italy). Dipt. di Chimica Organica; Bruno, M. [Istituto Superiore di Sanita' , Laboratorio di Igiene Ambientale, Rome (Italy)

2000-07-01

The coastal areas of the Southern Adriatic Sea, in particular the Apulian ones, may be considered an example of intact ecosystem and represent an ideal term of comparison to other marine ecosystems having higher levels of pollution (Northern Adriatic Sea). In order to evaluate the sanitary levels of this environment, four transect were investigated during two years monitoring (April 1995-March 1997) along the Otranto Channel coasts, by joint research groups of the Environmental Hygiene Laboratory of the Istituto Superiore di Sanita' and the Istituto Sperimentale Talassografico A. Cerruti of CNR in Taranto. The study underlines the phytoplanktic and bacterial population dynamics, and the detection of the microbiological water quality along the coast tract Brindisi-Lecce-Otranto-S. Maria di Leuca. The results acquired pointed out population dynamics of some potantially toxic species of Dinophysis genus and Pseudo-nitzschia delicatissima. These depended on the winter nutrient loads due to the ASW (Adriatic Superficial Waters) and to the LIW (Levantine Intermediate Waters). The bacterial community was mainly constituted by genera Aeromonas, Photobacterium, Cytophaga and Pseudomonas. Also the presence of Enterobacteriaceae family was relevant. Among the pathogenic vibrios the most frequently isolated species were Vibrio alginolyticus and Vibrio vulnificus. [Italian] Considerando che le zone del basso Adriatico, in particolare quelle pugliesi, costituiscono un biotopo ancora relativamente inalterato, esse sono state oggetto di un'indagine sperimentale condotta in 24 mesi di attivita' (aprile 1995-marzo 1997) lungo le coste del Canale di Otranto, ad opera di un gruppo congiunto del Laboratorio di Igiene Ambientale dell'Istituto Superiore di Sanita' e dei laboratori dell'Istituto Sperimentale Talassografico A. Cerruti del CNR di Taranto, ai fini di valutare lo stato di salute di questo ambiente, che fornisce, con buona probabilita', un

Tectonics vs. Climate efficiency in triggering detrital input in sedimentary basins: the Po Plain-Venetian-Adriatic Foreland Basin (Northern Italy)

Science.gov (United States)

Amadori, Chiara; Di Giulio, Andrea; Toscani, Giovanni; Lombardi, Stefano; Milanesi, Riccardo; Panara, Yuri; Fantoni, Roberto

2017-04-01

The relative efficiency of tectonics respect to climate in triggering erosion of mountain belts is a classical but still open debate in geosciences. The fact that data both from tectonically active and inactive mountain regions in different latitudes, record a worldwide increase of sediment input to sedimentary basins during the last million years concomitantly with the cooling of global climate and its evolution toward the modern high amplitude oscillating conditions pushed some authors to conclude that Pliocene-Pleistocene climate has been more efficient than tectonics in triggering mountain erosion. Po Plain-Venetian-Adriatic Foreland System, made by the relatively independent Po Plain-Northern Adriatic Basin and Venetian-Friulian Basin, provides an ideal case of study to test this hypothesis and possibly quantify the difference between the efficiency of the two. In fact it is a relatively closed basin (i.e. without significant sediment escape) with a fairly continuous sedimentation (i.e. with a quite continuous sedimentary record) completely surrounded by collisional belts (Alps, Northern Apennines and Dinarides) that experienced only very weak tectonic activity since Calabrian time, i.e. when climate cooling and cyclicity increased the most. We present a quantitative reconstruction of the sediment flow delivered from the surrounding mountain belts to the different part of the basin during Pliocene-Pleistocene time. This flow was obtained through the 3D reconstruction of the Venetian-Friulian and Po Plain Northern Adriatic Basins architecture, performed by means of the seismic-based interpretation and time-to-depth conversion of six chronologically constrained surfaces (seismic and well log data from courtesy of ENI); moreover, a 3D decompaction of the sediment volume bounded by each couple of surfaces has been included in the workflow, in order to avoid compaction-related bias. The obtained results show in both Basins a rapid four-folds increase of the

Comparative Morphometric Analysis of the Smallscaled Scorpionfish, Scorpaena Porcus (Scorpaenidae, Scorpaeniformes, from the Southern Coast of the Crimea and Eastern Part of the Adriatic Sea

Directory of Open Access Journals (Sweden)

Manilo L. G.

2016-12-01

Full Text Available Comparative analysis of morphometric characters of small-scaled scorpionfish from the Black Sea (near the southern coast of the Crimea and from the eastern part of the Adriatic Sea showed significant differences in males and females on thirteen plastic and three meristic characters. These differences may be due to unequal abiotic and biotic habitat conditions, and refer about the geographical variability of the species, indicating the presence of two different populations in the study area.

Sharing skills and needs between providers and users of climate information to create climate services: lessons from the Northern Adriatic case study

Directory of Open Access Journals (Sweden)

Valentina Giannini

2016-03-01

Full Text Available Abstract The need to cope with the expected impacts of climate change on socio-ecological systems calls for a closer dialogue between climate scientists and the community of climate information users. We describe an interactive process designed to bridge this gap by establishing a two-way communication, based on mutual learning. We analyse the need of climate information for the integrated assessment of climate change impacts on the coastal zone of the Northern Adriatic Sea, which is considered to be particularly vulnerable to several climate-related phenomena, e.g. heavy rainfall events, pluvial flood, and sea level rise, causing potentially high damage to coastal ecosystems and urban areas (e.g. acqua alta in the Venice Lagoon. A participatory process was designed engaging representatives from both the scientific and local stakeholders communities, and facilitated by a boundary organization, embodied by the Euro-Mediterranean Center on Climate Change. End-users of climate information (e.g. decision makers belonging to public institutions were selected among representatives of those public institutions having a specific mandate for Integrated Coastal Zone Management, and engaged to identify their needs. During the early stages of the interaction process, several priorities were identified, including: (1 data to support land-use planning, (2 data with greater resolution and longer time series, (3 data on climate impacts and risks, (4 precipitation patterns to improve irrigation, (5 sea level rise and tides, (6 climate variations and extreme events, (7 seasonal trend for tidal waves, and (8 hydraulic risk. Three climate products were developed to address these needs: (1 short-term projections of sea level rise; (2 seasonal predictions of extreme rainfall events; (3 long-term regional projections of climate extremes (including heat waves, dry spells and heavy rainfall events. Additionally, two risk products were developed: 4 sea level rise

Isotopic characteristics of shells Mytilus galloprovincialis from eastern coastal area of Adriatic Sea

Directory of Open Access Journals (Sweden)

Tjaša Kanduč

2006-06-01

Full Text Available Samples of Mytilus galloprovincialis were collected from entire Eastern Adriatic coast to determine δ18O and δ13C performed on calcite and aragonite shell layers. The aim of this work was to check whether shells of M. galloprovincialis are good environmental indicators (water temperature, salinity. Based on measured isotopic composition of oxygen in shell layers and assumed isotopic composition in water temperatures of calcite and aragonite of shell layers were calculated. The calculated temperatures for M. galloprovincialis shell growth of calcite and aragonite shell layer are in good agreement with measured temperatures of sea water. According to our results of δ18O and δ13C in shell layers we canseparate the locations of the investigated area into three groups: those with more influence of fresh water, those with less influence of fresh water and those of marine environments.

Decapod crustaceans associated with an artificial reef (Adriatic Sea

Directory of Open Access Journals (Sweden)

A. SANTELLI

2013-10-01

Full Text Available The aim of this study is to increase the knowledge on the distribution of decapod crustaceans associated with an artificial reef positioned on sandy-mud bottoms in the central Adriatic Sea. The reef is constituted of concrete modules assembled in pyramids and concrete poles. Hard and soft bottom samples were collected from 2001, just after reef construction, to 2005 (4 surveys per year. Regarding the soft seabed, three sites close to a pyramid, three inside the reef area at a distance of 10-15 m from the structures, and three 200 m outside the reef (control sites were randomly sampled during each survey. At the same time, three pyramids (vertical and horizontal walls and three poles were also investigated. After taxonomical analysis, decapod crustaceans were analysed using abundance and species richness. Sites and years were compared using a balanced, fixed effect, 2-way ANOVA and PERMANOVA. In addition, SIMPER analysis was performed to identify those species typifying each community inhabiting both the soft bottom and the artificial substrates. The results showed that the artificial reef induced an increase in both abundance and diversity of the decapods of the natural habitat. In fact, man-made substrates may offer new available space for biological colonization and allow the settlement of new species usually living on hard bottoms, thus increasing the complexity of the original benthic communities.

Early Spring Dust over the Mediterranean Sea

Science.gov (United States)

2002-01-01

The Sea-viewing Wide Field-of-view Sensor (SeaWiFS) observed this large cloud of dust (brownish pixels) blowing from northern Africa across the Mediterranean Sea on March 4, 2002. The dust can be seen clearly blowing across Southern Italy, Albania, Greece, and Turkey-all along the Mediterranean's northeastern shoreline. Notice that there also appears to be human-made aerosol pollution (greyish pixels) pooling in the air just south of the Italian Alps and blowing southeastward over the Adriatic Sea. The Alps can be easily identified as the crescent-shaped, snow-capped mountain range in the top center of this true-color scene. There also appears to be a similar haze over Austria, Hungary, and Yugoslavia to the north and east of Italy. Image courtesy the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

Population genomics meet Lagrangian simulations: Oceanographic patterns and long larval duration ensure connectivity among Paracentrotus lividus populations in the Adriatic and Ionian seas.

Science.gov (United States)

Paterno, Marta; Schiavina, Marcello; Aglieri, Giorgio; Ben Souissi, Jamila; Boscari, Elisa; Casagrandi, Renato; Chassanite, Aurore; Chiantore, Mariachiara; Congiu, Leonardo; Guarnieri, Giuseppe; Kruschel, Claudia; Macic, Vesna; Marino, Ilaria A M; Papetti, Chiara; Patarnello, Tomaso; Zane, Lorenzo; Melià, Paco

2017-04-01

Connectivity between populations influences both their dynamics and the genetic structuring of species. In this study, we explored connectivity patterns of a marine species with long-distance dispersal, the edible common sea urchin Paracentrotus lividus , focusing mainly on the Adriatic-Ionian basins (Central Mediterranean). We applied a multidisciplinary approach integrating population genomics, based on 1,122 single nucleotide polymorphisms (SNPs) obtained from 2b-RAD in 275 samples, with Lagrangian simulations performed with a biophysical model of larval dispersal. We detected genetic homogeneity among eight population samples collected in the focal Adriatic-Ionian area, whereas weak but significant differentiation was found with respect to two samples from the Western Mediterranean (France and Tunisia). This result was not affected by the few putative outlier loci identified in our dataset. Lagrangian simulations found a significant potential for larval exchange among the eight Adriatic-Ionian locations, supporting the hypothesis of connectivity of P. lividus populations in this area. A peculiar pattern emerged from the comparison of our results with those obtained from published P. lividus cytochrome b (cytb) sequences, the latter revealing genetic differentiation in the same geographic area despite a smaller sample size and a lower power to detect differences. The comparison with studies conducted using nuclear markers on other species with similar pelagic larval durations in the same Adriatic-Ionian locations indicates species-specific differences in genetic connectivity patterns and warns against generalizing single-species results to the entire community of rocky shore habitats.

Quantification of Dissolved and Particulate Polyunsaturated Aldehydes in the Adriatic Sea

Directory of Open Access Journals (Sweden)

Raffaella Casotti

2011-03-01

Full Text Available Polyunsaturated aldehydes (PUA are supposed to play critical roles in chemically-mediated plankton interactions. Laboratory studies suggest that they act as mediators of chemical defense and chemical communication. PUA are oxylipins containing an α,β,γ,δ-unsaturated aldehyde structure element and are mainly found in diatoms. We present here a detailed surface mapping of PUA during a spring bloom of the diatom Skeletonema marinoi in the Adriatic Sea. We monitored dissolved PUA, as well as particulate PUA, which are produced by phytoplankton after cell disintegration. Our survey revealed a patchy distribution of PUA and shows that at most stations S. marinoi is the major contributor to the overall PUA. Our data also suggest that lysis of a diatom bloom can contribute significantly to the dissolved PUA concentrations and that other producers, which are smaller in cell size compared to diatoms, have to be taken into account as well if the total PUA content of marine samples is considered. The analyses of samples collected in deeper water suggests that diatom contribution to PUA decreases with depth, while smaller-sized unidentified organisms take place as dominant contributors to the PUA concentrations.

226Ra activity in the mullet species Liza aurata and South Adriatic sea marine environment of Montenegro

International Nuclear Information System (INIS)

Antovic, N. M.; Antovic, I.; Svrkota, N.

2010-01-01

226 Ra activity in the South Adriatic Sea-water, surface sediment, mud with detritus, sea-grass (Posidonia oceanica) samples and the mullet (Mugilidae) species Liza aurata, as well as soil and sand from the Montenegrin Coast-was measured using the six-crystal gamma-coincidence spectrometer PRIPYAT-2M. The results are used for calculation of the absorbed (and annual effective) dose rates in air due to the 226 Ra gamma radiation. The absorbed dose rates ranged from 5.94 to 97.16 nGy h -1 (soil) and from 0.65 to 7.65 nGy h -1 (sand). In seawater 226 Ra activity is found to be from 0.08 to 0.15 Bq l -1 , while in whole L. aurata individuals from 0.58 to 1.97 Bq kg -1 . Annual intake of 226 Ra by human consumers of this fish species has been estimated to provide an effective dose of 0.006 mSv y -1 . (authors)

Temporal variability in SeaWiFS derived apparent optical properties in European seas

Science.gov (United States)

Vantrepotte, V.; Mélin, F.

2010-02-01

The 10-year record of ocean color data provided by the SeaWiFS mission is an important asset for monitoring and research activities conducted on the optically complex European seas. This study makes use of the SeaWiFS data set of normalized water leaving radiances LWN to study the major characteristics of temporal variability associated with optical properties across the entire European domain. Specifically, the time series of LWN and associated band ratios are decomposed into terms representing a fixed seasonal cycle, irregular variations and trends, and the contribution of these components to the total variance is described for the various basins. The diversity of the European waters is fully reflected by the range of results varying with regions and wavelengths. Generally, the Mediterranean and Baltic seas appear as two end-members with, respectively, high and low contributions of the seasonal component to the total variance. The existence of linear trends affecting the satellite products is also explored for each basin. By focusing the analysis on LWN and band ratios, the validity of the results is not limited by the varying levels of uncertainty that characterize derived products such as the concentration of chlorophyll a in optically complex waters. Statistically significant, and in some cases large, trends are detected in the Atlantic Ocean west of the European western shelf, the central North Sea, the English Channel, the Black Sea, the northern Adriatic, and various regions of the Mediterranean Sea and the northern Baltic Sea, revealing changes in the concentrations of optically significant constituents in these regions.

An Amphibious Seismic Study of the Crustal Structure of the Adriatic Microplate

Science.gov (United States)

Dannowski, A.; Kopp, H.; Schurr, B.; Improta, L.; Papenberg, C. A.; Krabbenhoeft, A.; Argnani, A.; Ustaszewski, K. M.; Handy, M.; Glavatovic, B.

2016-12-01

The present-day structure of the southern Adriatic area is controlled by two oppositely-vergent fold-and-thrust belt systems (Apennines and Dinarides). The Adriatic continental domain is one of the most enigmatic segments of the Alpine-Mediterranean collision zone. It separated from the African plate during the Mesozoic extensional phase that led to the opening of the Ionian Sea. Basin widening and deepening peaked during Late Triassic-Liassic extension, resulting in the formation of the southern Adriatic basin, bounded on either side by the Dinaric and Apulian shallow water carbonate platforms. Because of its present foreland position with respect to the Dinaric part of orogenic belt, the southern Adriatic basin represents the only remnant of the Neotethyan margin and offers the unique opportunity to image a segment of Mesozoic passive margin in the Mediterranean. To study the deep crustal structure, the upper mantle and the shape of the plate margin, the German research vessel Meteor acquired 2D seismic refraction and wide-angle reflection data during an onshore-offshore experiment (cruise M86-3). We present two profiles: Profile P03 crossed Adria from the Gargano Promontory into Albania. A second profile (P01) was shot parallel to the coastlines, extending from the southern Adriatic basin to a possible mid-Adriatic strike-slip fault that purportedly segments the Adriatic microplate. Two different approaches of travel time tomography are applied to the data set: A non-linear approach is used for the shorter profile P01. A linear approach is applied to profile P03 (360 km length) and allows for the integration of the 36 ocean bottom stations and 19 land stations. First results show a good resolution of the sedimentary part of the Adriatic region. The depth of the basement as well as the depth of the Moho discontinuity vary laterally and deepen towards the North-East, consistent with the notion of flexural loading of the externally propagating orogenic wedge of the

Southern Adriatic sea as a potential area for CO2 geological storage

International Nuclear Information System (INIS)

Volpi, V.; Forlin, F.; Donda, F.; Civile, D.; Facchin, L.; Sauli, L.; Merson, B.; Sinza-Mendieta, K.; Shams, A.

2015-01-01

The Southern Adriatic Sea is one of the five prospective areas for CO 2 storage being evaluated under the three year (FP7) European SiteChar project dedicated to the characterization of European CO 2 storage sites. The potential reservoir for CO 2 storage is represented by a carbonate formation, the wackstones and packstones of the Scaglia Formation (Upper Cretaceous-Paleogene). In this paper, we present the geological characterization and the 3D modeling that led to the identification of three sites, named Grazia, Rovesti and Grifone, where the Scaglia Formation, with an average thickness of 50 m, reveals good petrophysical characteristics and is overlain by an up to 1 200 thick cap-rock. The vicinity of the selected sites to the Enel - Federico II power plant (one of the major Italian CO 2 emitter) where a pilot plant for CO 2 capture has been already started in April 2010, represents a good opportunity to launch the first Carbon Capture and Storage (CCS) pilot project in Italy and to apply this technology at industrial level, strongly contributing at the same time at reducing the national CO 2 emissions. (authors)

Winter cooling in the northern Arabian Sea

Digital Repository Service at National Institute of Oceanography (India)

PrasannaKumar, S.; Prasad, T.G.

forcing that leads to the observed high productivity during winter in the northern Arabian Sea. The weak northerly winds and increased solar insolation during the inter-monsoon period, led to the development of a highly stratified upper layer with warm sea...

A P-Vector Approach to Absolute Geostrophic Currents in the Adriatic Sea

National Research Council Canada - National Science Library

Pinto, Renato

1998-01-01

.... As part of this project, the OGEX1 cruise was conducted between 19 and 24 May 1995 with focus in the Otranto Strait, through which the Adriatic is connected to the rest of the Mediterranean basin...

Plastic litter in sediments from the Croatian marine protected area of the natural park of Telaščica bay (Adriatic Sea).

Science.gov (United States)

Blašković, Andrea; Fastelli, Paolo; Čižmek, Hrvoje; Guerranti, Cristiana; Renzi, Monia

2017-01-15

This paper reports baseline levels of litter (macro, meso and microplastics) in sediments collected from different areas of the Croatian MPA of the Natural Park of Telaščica bay (Adriatic Sea, GSA n. 17). The distribution of total abundance according to size, for all analysed locations evidences that microplastics are the dominant fraction concerning item's numbers. In all analysed samples no macroplastics were found, while microplastics are 88.71% and mesoplastics are 11.29% of the total. Copyright © 2016 Elsevier Ltd. All rights reserved.

Dispersal of Sediment in the Western Adriatic during Energetic Wintertime Forcing

Science.gov (United States)

Harris, C. K.; Sherwood, C. R.; Mullenbach, B. L.; Pullen, J. D.

2003-12-01

EuroSTRATAFORM aims to relate sediment delivery and reworking to seabed morphology and stratigraphy through observations and modeling of water column transport. The Po River dominates buoyancy and sediment input into the Adriatic Sea, but small Apeninne rivers (the Chienti, Pescara, etc.) may produce locally important signals. Sedimentation is influenced by fluvial supply, resuspension by waves and currents, and transport by oceanographic currents forced by winds and buoyancy. Transport is likely highest during times of energetic forcing; including Bora events with northeasterly winds and Sirocco events with southeasterly winds. It is difficult, from field measurements alone, to characterize dispersal and convergence patterns over the relevant spatial scales. We applied a three-dimensional hydrodynamic model that includes fluvial delivery, transport, resuspension, and deposition of sediment to quantify sediment dispersal with a 2-km resolution over the entire Adriatic. Circulation calculations were driven by spatially- and temporally-varying wind fields for the Fall / Winter of 2002 / 2003 and realistic Po and Apennine river discharges. Waves were hindcast with the SWAN model. Dispersion of both resuspended and river-derived sediment was estimated for periods that contained intense Bora and Sirocco winds. Predicted sediment dispersal rates and patterns are sensitive to forcing winds, buoyancy flux, and wave patterns. Higher sediment flux was predicted during Bora conditions than during Sirocco conditions. Sirocco winds weaken the Western Adriatic Coastal Current (WACC), and because they tend to concentrate over the Eastern Adriatic, they often fail to create especially energetic waves in the Western Adriatic. Bora wind conditions, on the other hand, intensify the WACC and can build high wave energies over the northwestern Adriatic. Most of the sediment transport occurs during Bora, with a net southward flux. These predictions will be compared to field observations

RIGED-RA project - Restoration and management of Coastal Dunes in the Northern Adriatic Coast, Ravenna Area - Italy

Science.gov (United States)

Giambastiani, Beatrice M. S.; Greggio, Nicolas; Sistilli, Flavia; Fabbri, Stefano; Scarelli, Frederico; Candiago, Sebastian; Anfossi, Giulia; Lipparini, Carlo A.; Cantelli, Luigi; Antonellini, Marco; Gabbianelli, Giovanni

2016-10-01

Coastal dunes play an important role in protecting the coastline. Unfortunately, in the last decades dunes have been removed or damaged by human activities. In the Emilia- Romagna region significant residual dune systems are found only along Ravenna and Ferrara coasts. In this context, the RIGED-RA project “Restoration and management of coastal dunes along the Ravenna coast” (2013-2016) has been launched with the aims to identify dynamics, erosion and vulnerability of Northern Adriatic coast and associated residual dunes, and to define intervention strategies for dune protection and restoration. The methodology is based on a multidisciplinary approach that integrates the expertise of several researchers and investigates all aspects (biotic and abiotic), which drive the dune-beach system. All datasets were integrated to identify test sites for applying dune restoration. The intervention finished in April 2016; evolution and restoration efficiency will be assessed.

Multisensor Analyzed Sea Ice Extent - Northern Hemisphere (MASIE-NH)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The Multisensor Analyzed Sea Ice Extent Northern Hemisphere (MASIE-NH) products provide measurements of daily sea ice extent and sea ice edge boundary for the...

Nitrite maxima in the Northern Arabian Sea

Digital Repository Service at National Institute of Oceanography (India)

Sankaranarayanan, V.N.; DeSousa, S.N.; Fondekar, S.P.

There are 2 nitrite maxima in the Northern Arabian Sea, one at the thermocline depth and the other at depths between 300 and 500 m. The 2nd maximum is more prominent in the northeastern part of the Arabian Sea. The 1st maximum is associated...

Border Reconstruction of Bosnia and Herzegovina's Access to the Adriatic Sea at Sutorina by Consulting Old Maps

Directory of Open Access Journals (Sweden)

Nedim Tuno

2011-12-01

Full Text Available The paper presents the results of scientific research into the former southernmost Bosnian border by analyzing historical maps. In cartographic representations of the area (created between the mid-17th and mid-20th centuries, state and administrative boundary lines are clearly demarcated. They provide indisputable proof that the Sutorina area belonged to Bosnia and Herzegovina through many centuries, providing access to the Adriatic Sea. The maps presented follow the course of the historical changes in the area which shaped its borders. The extent of the narrow Sutorina corridor was observed by combining data on boundary lines taken from historical maps with the current situation in the area. The technique of georeferencing old maps based on a genetic algorithm was developed for this purpose. 

Thermal refugia against coral bleaching throughout the northern Red Sea

KAUST Repository

Osman, Eslam O.; Smith, David J.; Ziegler, Maren; Kü rten, Benjamin; Conrad, Constanze; El-Haddad, Khaled M.; Voolstra, Christian R.; Suggett, David J.

2017-01-01

Tropical reefs have been impacted by thermal anomalies caused by global warming that induced coral bleaching and mortality events globally. However, there have only been very few recordings of bleaching within the Red Sea despite covering a latitudinal range of 15° and consequently it has been considered a region that is less sensitive to thermal anomalies. We therefore examined historical patterns of sea surface temperature (SST) and associated anomalies (1982–2012) and compared warming trends with a unique compilation of corresponding coral bleaching records from throughout the region. These data indicated that the northern Red Sea has not experienced mass bleaching despite intensive Degree Heating Weeks (DHW) of >15°C-weeks. Severe bleaching was restricted to the central and southern Red Sea where DHWs have been more frequent, but far less intense (DHWs <4°C-weeks). A similar pattern was observed during the 2015–2016 El Niño event during which time corals in the northern Red Sea did not bleach despite high thermal stress (i.e. DHWs >8°C-weeks), and bleaching was restricted to the central and southern Red Sea despite the lower thermal stress (DHWs < 8°C-weeks). Heat stress assays carried out in the northern (Hurghada) and central (Thuwal) Red Sea on four key reef-building species confirmed different regional thermal susceptibility, and that central Red Sea corals are more sensitive to thermal anomalies as compared to those from the north. Together, our data demonstrate that corals in the northern Red Sea have a much higher heat tolerance than their prevailing temperature regime would suggest. In contrast, corals from the central Red Sea are close to their thermal limits, which closely match the maximum annual water temperatures. The northern Red Sea harbours reef-building corals that live well below their bleaching thresholds and thus we propose that the region represents a thermal refuge of global importance.

Thermal refugia against coral bleaching throughout the northern Red Sea

KAUST Repository

Osman, Eslam O.

2017-10-17

Tropical reefs have been impacted by thermal anomalies caused by global warming that induced coral bleaching and mortality events globally. However, there have only been very few recordings of bleaching within the Red Sea despite covering a latitudinal range of 15° and consequently it has been considered a region that is less sensitive to thermal anomalies. We therefore examined historical patterns of sea surface temperature (SST) and associated anomalies (1982–2012) and compared warming trends with a unique compilation of corresponding coral bleaching records from throughout the region. These data indicated that the northern Red Sea has not experienced mass bleaching despite intensive Degree Heating Weeks (DHW) of >15°C-weeks. Severe bleaching was restricted to the central and southern Red Sea where DHWs have been more frequent, but far less intense (DHWs <4°C-weeks). A similar pattern was observed during the 2015–2016 El Niño event during which time corals in the northern Red Sea did not bleach despite high thermal stress (i.e. DHWs >8°C-weeks), and bleaching was restricted to the central and southern Red Sea despite the lower thermal stress (DHWs < 8°C-weeks). Heat stress assays carried out in the northern (Hurghada) and central (Thuwal) Red Sea on four key reef-building species confirmed different regional thermal susceptibility, and that central Red Sea corals are more sensitive to thermal anomalies as compared to those from the north. Together, our data demonstrate that corals in the northern Red Sea have a much higher heat tolerance than their prevailing temperature regime would suggest. In contrast, corals from the central Red Sea are close to their thermal limits, which closely match the maximum annual water temperatures. The northern Red Sea harbours reef-building corals that live well below their bleaching thresholds and thus we propose that the region represents a thermal refuge of global importance.

The Coastal Observing System for Northern and Arctic Seas (COSYNA)

OpenAIRE

Baschek, Burkard; Schroeder, Friedhelm; Brix, Holger; Riethmüller, Rolf; Badewien, Thomas H.; Breitbach, Gisbert; Brügge, Bernd; Colijn, Franciscus; Doerffer, Roland; Eschenbach, Christiane; Friedrich, Jana; Fischer, Philipp; Garthe, Stefan; Horstmann, Jochen; Krasemann, Hajo

2017-01-01

The Coastal Observing System for Northern and Arctic Seas (COSYNA) was established in order to better understand the complex interdisciplinary processes of northern seas and the Arctic coasts in a changing environment. Particular focus is given to the German Bight in the North Sea as a prime example of a heavily used coastal area, and Svalbard as an example of an Arctic coast that is under strong pressure due to global change. The COSYNA automated observing and modelling system is designed...

Atmospheric Forcing of the Winter Air–Sea Heat Fluxes over the Northern Red Sea

KAUST Repository

Papadopoulos, Vassilis P.; Abualnaja, Yasser; Josey, Simon A.; Bower, Amy; Raitsos, Dionysios E.; Kontoyiannis, Harilaos; Hoteit, Ibrahim

2013-01-01

The influence of the atmospheric circulation on the winter air–sea heat fluxes over the northern Red Sea is investigated during the period 1985–2011. The analysis based on daily heat flux values reveals that most of the net surface heat exchange variability depends on the behavior of the turbulent components of the surface flux (the sum of the latent and sensible heat). The large-scale composite sea level pressure (SLP) maps corresponding to turbulent flux minima and maxima show distinct atmospheric circulation patterns associated with each case. In general, extreme heat loss (with turbulent flux lower than −400 W m−2) over the northern Red Sea is observed when anticyclonic conditions prevail over an area extending from the Mediterranean Sea to eastern Asia along with a recession of the equatorial African lows system. Subcenters of high pressure associated with this pattern generate the required steep SLP gradient that enhances the wind magnitude and transfers cold and dry air masses from higher latitudes. Conversely, turbulent flux maxima (heat loss minimization with values from −100 to −50 W m−2) are associated with prevailing low pressures over the eastern Mediterranean and an extended equatorial African low that reaches the southern part of the Red Sea. In this case, a smooth SLP field over the northern Red Sea results in weak winds over the area that in turn reduce the surface heat loss. At the same time, southerlies blowing along the main axis of the Red Sea transfer warm and humid air northward, favoring heat flux maxima.

Atmospheric Forcing of the Winter Air–Sea Heat Fluxes over the Northern Red Sea

KAUST Repository

Papadopoulos, Vassilis P.

2013-03-01

The influence of the atmospheric circulation on the winter air–sea heat fluxes over the northern Red Sea is investigated during the period 1985–2011. The analysis based on daily heat flux values reveals that most of the net surface heat exchange variability depends on the behavior of the turbulent components of the surface flux (the sum of the latent and sensible heat). The large-scale composite sea level pressure (SLP) maps corresponding to turbulent flux minima and maxima show distinct atmospheric circulation patterns associated with each case. In general, extreme heat loss (with turbulent flux lower than −400 W m−2) over the northern Red Sea is observed when anticyclonic conditions prevail over an area extending from the Mediterranean Sea to eastern Asia along with a recession of the equatorial African lows system. Subcenters of high pressure associated with this pattern generate the required steep SLP gradient that enhances the wind magnitude and transfers cold and dry air masses from higher latitudes. Conversely, turbulent flux maxima (heat loss minimization with values from −100 to −50 W m−2) are associated with prevailing low pressures over the eastern Mediterranean and an extended equatorial African low that reaches the southern part of the Red Sea. In this case, a smooth SLP field over the northern Red Sea results in weak winds over the area that in turn reduce the surface heat loss. At the same time, southerlies blowing along the main axis of the Red Sea transfer warm and humid air northward, favoring heat flux maxima.

The Adriatic response to the bora forcing. A numerical study

International Nuclear Information System (INIS)

Rachev, N.

2001-01-01

This paper deals with the bora wind effect on the Adriatic Sea circulation as simulated by a 3-D numerical code (the DieCAST model). The main result of this forcing is the formation of intense upwelling along the eastern coast in agreement with previous theoretical studies and observations. Different numerical experiments are discussed for various boundary and initial conditions to evaluate their influence on both circulation and upwelling patterns

Active stress from earthquake focal mechanisms along the Padan-Adriatic side of the Northern Apennines (Italy), with considerations on stress magnitudes and pore-fluid pressures

Science.gov (United States)

Boncio, Paolo; Bracone, Vito

2009-10-01

The active tectonic regime along the outer Northern Apennines (Padan-Adriatic area) is a matter of debate. We analyse the active tectonic regime by systematically inverting earthquake focal mechanisms in terms of their driving stress field, comparing two different stress inversion methods. Earthquakes within the area often deviate from Andersonian conditions, being characterized by reverse or transpressional slip on high-angle faults even if the regime is almost purely thrust faulting (e.g. Reggio Emilia 1996 and Faenza 2000 earthquakes). We analyse the stress conditions at faulting for the Reggio Emilia and Faenza earthquakes in order to infer the stress magnitudes and the possible role of fluid pressures. The stress analysis defines a consistent pattern of sub-horizontal active deviatoric compression arranged nearly perpendicular to the eastern front of the Padan-Adriatic fold-and-thrust system, independent of the stress inversion method used. The results are consistent with active compression operating within the Padan-Adriatic belt. The stress field is thrust faulting (sub-vertical σ3), except for the Cesena-Forlì and Ancona areas, where a strike-slip regime (sub-vertical or steeply-plunging σ2) operates. The strike-slip regimes are interpreted as being caused by the superposition of local tensional stresses due to oroclinal bending (i.e. rotations of the belt about vertical axes) on the regional compressional stress field. Kinematic complexities characterize the 1996 Reggio Emilia seismic sequence. The distribution of these complexities is not random, suggesting that they are due to local variations of the regional stress field within the unfaulted rocks surrounding the coseismic rupture. The stress conditions at faulting for the Reggio Emilia 1996 and Faenza 2000 earthquakes, coupled with the observation that seismicity in the Padan-Adriatic area often occurs in swarms, suggest that high pore-fluid pressures (Pf ≥ 70% of the lithostatic load) operate

Calibration and Validation of A One-dimensional Complex Marine Biogeochemicalfluxes Model In Different Areas of The Northern Adriatic Shelf.

Science.gov (United States)

Vichi, M.; Oddo, P.; Zavatarelli, M.; Coluccelli, A.; Coppini, G.; Celio, M.; Fonda Umani, S.; Pinardi, N.

In this contribution we show results from numerical simulations carried out with a complex biogeochemical fluxes model coupled with a one-dimensional high-resol ution hydrodynamical model and implemented at three different locations of the north- ern Adriatic shelf . One location is directly affected by Po river influence, one has more open-sea characteristics and one is located in the Gulf of Trieste with an in- termediate behavior; emphasis is put on the comparison with observations and on the functioning of the northern Adriatic ecosystem in the three areas. The work has been performed in a climatological context and has to be considered as preliminary to the development of three-dimensional numerical simulations. Biogeochemical model parameterizations have been ameliorated with a detailed description of bacterial sub- strate utilization associated to the quality of the dissolved organic matter (DOM) in order to improve model skill in capturing the observed DOM dynamics in the basin. The coupled model has been calibrated and validated at the three locations by means of climatological datasets. Results show satisfactory model behavior in simulating local seasonal dynamics in the limit of the available boundary conditions and the one-dimensional implementation. Comparisons with available in situ measurements of primary and bacterial production and bacterial abundances have been performed in all locations. Model simulated rates and bacterial dynamics are in the same order of magnitude of observations and show a qualitatively correct time evolution. The importance of temperature as a factor controlling bacteria efficiency is investigated with sensitivity experiments on the model parameterizations. The different model be- havior and pelagic ecosystem structure developed by the model at the three location can be attributed to the local hydrodynamical features and interactions with external inputs of nutrients. The onset of the winter/spring bloom in the climatological

Combined effects of the herbicide terbuthylazine and temperature on different flagellates from the Northern Adriatic Sea.

Science.gov (United States)

Fiori, Emanuela; Mazzotti, Matilde; Guerrini, Franca; Pistocchi, Rossella

2013-03-15

The triazinic herbicide terbuthylazine (TBA) is becoming an emergent contaminant in Italian rivers and in coastal and groundwater. A preliminary analysis of the sensitivity of marine flagellates to TBA was performed by monitoring the photosynthetic efficiency of nine species (belonging to the Dinophyceae or Raphidophyceae class) isolated from the Adriatic Sea. Different sensitivity levels for each flagellate were observed and the most sensitive microalgae, based on PSII inhibition, were: Gonyaulax spinifera>Fibrocapsa japonica>Lingulodinium polyedrum while the most resistant were two species belonging to the Prorocentrum genus. Then the response of two microalgae to drivers, such as temperature and terbuthylazine, applied in combination was also investigated. Two potentially toxic flagellates, Prorocentrum minimum and G. spinifera, were exposed, under different temperature conditions (15, 20 and 25°C), to TBA concentrations that did not completely affect PSII. For both flagellates, effects of TBA on algal growth, measured through cell density and carbon analysis, as well as on the photosynthetic activity are reported. All parameters analyzed showed a negative effect of TBA from the exponential phase. TBA effect on algal growth was significantly enhanced at the optimal temperature conditions (20 and 25°C), while no difference between control and herbicide treatments were detected for G. spinifera grown at 15°C, which represented a stress condition for this species. The maximum inhibition of photosynthetic efficiency was found at 20°C for both organisms. Both flagellates increased cell carbon and nitrogen content in herbicide treatments compared to the control, except G. spinifera grown at 15°C. Chlorophyll-a production was increased only in G. spinifera exposed to 5 μg L(-1) of TBA and the effect was enhanced with the increase of temperature. Herbicide-induced variations in cellular components determined changes in cellular carbon:nitrogen (C:N) and

Comparison of benthic indices for the evaluation of ecological status of three Slovenian transitional water bodies (northern Adriatic).

Science.gov (United States)

Pitacco, Valentina; Lipej, Lovrenc; Mavrič, Borut; Mistri, Michele; Munari, Cristina

2018-04-01

Benthic indicators are important tools for the classification of coastal and transitional water bodies. The aim of the work was to assess for the first time the Environmental Status (ES) of Slovenian transitional waters, comparing the following biotic indices: richness, Shannon-Weaver diversity, AMBI, M-AMBI, BENTIX and BITS indices. A total of 13 stations were sampled with a Van Veen grab, in three ecosystems in the northern Adriatic. Samples were sieved and sorted, invertebrates identified and counted. The anthropogenic impact was estimated with professional judgement. Richness and diversity showed a good response to anthropogenic pressure. Conversely, indices based on sensitivity/tolerance groups did not showed a clear distinction between more and less impacted ecosystems. In particular BENTIX underestimated the ES, while with BITS there was a overestimation. The best evaluation was obtained with M-AMBI, because even if based on a sensitivity/tolerance approach, it considered also the structural aspect of the community. Copyright © 2017 Elsevier Ltd. All rights reserved.

Late Cretaceous intra-oceanic magmatism in the internal Dinarides (northern Bosnia and Herzegovina): Implications for the collision of the Adriatic and European plates

Science.gov (United States)

Ustaszewski, Kamil; Schmid, Stefan M.; Lugović, Boško; Schuster, Ralf; Schaltegger, Urs; Bernoulli, Daniel; Hottinger, Lukas; Kounov, Alexandre; Fügenschuh, Bernhard; Schefer, Senecio

2009-03-01

The Kozara Mountains of northern Bosnia and Hercegovina form part of the internal Dinarides and host two tectonically juxtaposed ophiolitic successions of different age. The southern part of the Kozara Mountains exposes the Western Vardar Ophiolitic Unit, which was obducted onto the Adriatic margin in the Late Jurassic. The northern part exposes a bimodal igneous succession that was thrust onto the Western Vardar Ophiolitic Unit during the latest Cretaceous to Early Paleogene. This bimodal igneous succession comprises isotropic gabbros, doleritic dikes, basaltic pillow lavas and rhyolites. Pelagic limestones, intercalated with pillow lavas, yielded a Campanian globotruncanid association, consistent with concordant U-Pb ages on zircons from dolerites and rhyolites of 81.39 ± 0.11 and 81.6 ± 0.12 Ma, respectively. Chondrite-normalised rare earth element patterns of the bimodal igneous rocks show enrichment of LREE over HREE. Primitive mantle-normalised multi-element diagrams do not reveal significant depletion of HFSE. The ɛNd(T) and initial 87Sr/ 86Sr isotopic values range from + 4.4 to + 6.3 and from 0.70346 to 0.70507 respectively, suggesting an intraoceanic origin. The bimodal igneous succession is unconformably overlain by Maastrichtian to Paleocene siliciclastics that contain abundant ophiolitic detritus, suggesting reworking of the Campanian magmatics. An Eocene turbiditic sandstone succession unconformably covers both the Western Vardar Ophiolitic Unit and the Late Cretaceous bimodal igneous successions. These observations suggest that the Adriatic Plate and the Europe-derived Tisza and Dacia Mega-Units were still separated by a deep basin floored by oceanic lithosphere until the Campanian and that its closure did not occur before the Maastrichtian to earliest Paleogene. This Late Cretaceous oceanic domain probably represented a remnant of the Vardar Ocean, or alternatively, the Alpine Tethys; possibly the traces of both oceanic domains were connected in

Global change and relative sea level rise at Venice: what impact in term of flooding

Energy Technology Data Exchange (ETDEWEB)

Carbognin, Laura; Tosi, Luigi [Institute of Marine Sciences, National Research Council, Venice (Italy); Teatini, Pietro [Institute of Marine Sciences, National Research Council, Venice (Italy); University of Padova, Department of Mathematical Methods and Models for Scientific Applications, Padua (Italy); Tomasin, Alberto [Institute of Marine Sciences, National Research Council, Venice (Italy); University Ca' Foscari in Venice, Venice (Italy)

2010-11-15

Relative sea level rise (RSLR) due to climate change and geodynamics represents the main threat for the survival of Venice, emerging today only 90 cm above the Northern Adriatic mean sea level (msl). The 25 cm RSLR occurred over the 20th century, consisting of about 12 cm of land subsidence and 13 cm of sea level rise, has increased the flood frequency by more than seven times with severe damages to the urban heritage. Reasonable forecasts of the RSLR expected to the century end must be investigated to assess the suitability of the Mo.S.E. project planned for the city safeguarding, i.e., the closure of the lagoon inlets by mobile barriers. Here we consider three RSLR scenarios as resulting from the past sea level rise recorded in the Northern Adriatic Sea, the IPCC mid-range A1B scenario, and the expected land subsidence. Available sea level measurements show that more than 5 decades are required to compute a meaningful eustatic trend, due to pseudo-cyclic 7-8 year long fluctuations. The period from 1890 to 2007 is characterized by an average rate of 0.12 {+-} 0.01 cm/year. We demonstrate that linear regression is the most suitable model to represent the eustatic process over these 117 year. Concerning subsidence, at present Venice is sinking due to natural causes at 0.05 cm/year. The RSLR is expected to range between 17 and 53 cm by 2100, and its repercussions in terms of flooding frequency are associated here to each scenario. In particular, the frequency of tides higher than 110 cm, i.e., the value above which the gates would close the lagoon to the sea, will increase from the nowadays 4 times per year to a range between 20 and 250. These projections provide a large spread of possible conditions concerning the survival of Venice, from a moderate nuisance to an intolerable aggression. Hence, complementary solutions to Mo.S.E. may well be investigated. (orig.)

First report of the planktonic copepod Oithona davisae in the northern Wadden Sea (North Sea): Evidence for recent invasion?

Science.gov (United States)

Cornils, Astrid; Wend-Heckmann, Britta

2015-06-01

In October 2010, specimens of Oithona were taken from the List Tidal Basin in the northern Wadden Sea (North Sea) for a biogeographic study on Oithona similis. These specimens could not be assigned to O. similis or any of the other Oithona species known from the North Sea genetically. These specimens were identified as Oithona davisae Ferrari and Orsi 1984, a Northwest Pacific species, known as an invasive species from the Black Sea and the northwestern Mediterranean Sea. Recent sampling provided evidence that O. davisae is still present in the northern Wadden Sea and may thus now be a permanent plankton species.

On the impact of the Bimodal Oscillating System (BiOS on the biogeochemistry and biology of the Adriatic and Ionian Seas (Eastern Mediterranean

Directory of Open Access Journals (Sweden)

G. Civitarese

2010-12-01

Full Text Available Analysis of 20-year time-series of the vertically averaged salinity and nutrient data in the Southern Adriatic shows that the two parameters are subject to strong decadal variability. In addition, it is documented that nutrient and salinity variations are out of phase. Nutrients in the Ionian and in the Adriatic vary in parallel except that generally the nutrient content in the Adriatic is lower than in the Ionian, a fact that has been attributed to primary producer consumption following the winter convective mixing. As shown earlier, North Ionian Gyre (NIG changes its circulation sense on a decadal scale due to the Bimodal Oscillating System, i.e. the feedback mechanism between the Adriatic and Ionian. Cyclonic circulation causes a downwelling of the nitracline along the borders of the NIG and a decrease in the nutrient content of the water flowing into the Adriatic across the Otranto Strait, and vice versa. In addition, the highly oligotrophic central area of the Ionian shows annual blooms only during cyclonic NIG circulation. Inversion of the sense of the NIG results in the advection of Modified Atlantic Water or of the Levantine/Eastern Mediterranean waters in the Adriatic. Here, we show that the presence of allochtonous organisms from Atlantic/Western Mediterranean and Eastern Mediterranean/temperate zone in the Adriatic are concurrent with the anticyclonic and cyclonic circulations of the NIG, respectively. On the basis of the results presented, a revision of the theory of Adriatic ingressions formulated in the early 1950s is proposed.

On the dense water cascading in the Southern Adriatic Sea during 2012: Setup of a Rapid Environmental Assessment

Science.gov (United States)

Langone, Leonardo

2013-04-01

In the North Adriatic, Dense Shelf Water (DSW) forms during cold and dry winters by cooling and evaporation. DSW spreads southward along the western shelf reaching the southern Adriatic basin (1200 m deep) after 1-2 months, where sinks through cascading events. In February 2012, a large Siberian High caused blocking of the Atlantic flow and a westward flow of dry and cold air masses from eastern Russia toward Europe. The North Adriatic experienced a cold spell with large decrease of surface temperature (3° -6° C) associated to severe cold and dry Bora wind. The result was the formation of extremely dense shelf water, further made possible by the very limited discharge of the Po river in the preceding autumn. As contribution to the Italian research programme RITMARE (Italian Research for the Sea), CNR-ISMAR set up a Rapid Environmental Assessment (REA) experiment to study the occurrence, amount, timing and properties of the newly formed DSW. Setting up REA strategies is crucial for several scientific and practical reasons: (i) capturing extreme events to improve our understanding of natural systems in a global-change scenario; (ii) to evaluate their impact on marine systems and the biota; (iii) to address issues related to fluctuating fish stocks as well as (iv) C export and sequestration in the deep sea. The experiment was designed with an integrated approach, including modeling simulations, mooring deployments and quick-response oceanographic cruises. Based on numerical model ensemble, the arrival time of the DSW at the Gargano Cape was forecasted likely starting after March 15, 2012, thus moorings were deployed few days before. Five moorings were deployed in sites selected on the basis of modelling predictions and geology-driven inferences defining areas where the passage of dense shelf water is most likely to occur. Moorings were equipped with down-looking ADCPs, automatic sediment traps, temperature loggers, recorders of temperature, conductivity and

Some trace elements in the waters, marine organisms and sediments of the Adriatic by neutron activation analysis

International Nuclear Information System (INIS)

Kosta, L.; Ravnik, V.; Byrne, A.R.; Dermelj, M.; Stirn, J.

1978-01-01

A number of investigations of trace elements in the waters, organisms and sediments of the Adriatic, using neutron activation analysis with radiochemical separations are reported. These include studies of Hg in mussels from the Northern Adriatic, of Hg and Se in edible animals from the Rijeka region, and of seven elements (As, Cd, Cu, Hg, Mn, Se and Zn) in marine invertebrates from the Slovene coast. Additionally, plankton, sediment cores and water samples were taken from a grid of stations covering the whole Adriatic and analyzed for 6 to 11 of the trace elements As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Sb and Zn (Hg only in water). Generally, levels found were not indicative of pollution as compared with oceanic samples, but some evidence of locally increased levels was found, especially for Hg. The levels of eleven trace elements in three marine Intercomparison samples prepared by the IAEA Monaco Laboratory are also presented. (T.G.)

Water-gas dynamics and coastal land subsidence over Chioggia Mare field, northern Adriatic Sea

Science.gov (United States)

Teatini, Pietro; Baú, Domenico; Gambolati, Giuseppe

2000-09-01

A major development programme comprising 15 gas fields of the northern Adriatic Sea has recently been submitted to the Ministry of the Environment, VIA Committee for the assessment of the environmental impact, by ENI-Agip, the Italian national oil company. One of the largest reservoirs is Chioggia Mare, located about 10 km offshore of the Venetian littoral, with a burial depth of 1000-1400 m. The planned gas production from this field is expected to impact the shoreline stability with a potential threat to the city of Venice, 25 km northwest of the center of Chioggia Mare. To evaluate the risk of anthropogenic land subsidence due to gas withdrawal, a numerical model was developed that predicts the compaction of both the gas-bearing formations and the lateral/bottom aquifer (water drive) during a 13-year producing and a 12-year post-production period, and the transference of the deep compaction to the ground surface. To address the uncertainty of a few important hydromechanical parameters, several scenarios are simulated and the most pessimistic predictions obtained. The modeling results show that at most 1 cm of land subsidence over 25 years may be expected at the city of Chioggia, whereas Venice is not subject to settlement. If aquifer drawdown is mediated by water injection, land subsidence is arrested 5 km offshore, with the Chioggia littoral zone experiencing a rebound of 0.6-0.7 cm. Résumé. Un important programme de développement portant sur 15 gisements de gaz du nord de l'Adriatique a été récemment soumis au Comité VIA pour l'évaluation de l'impact sur l'environnement du Ministère de l'Environnement, par la société ENI-Agip, la compagnie nationale pétrolière italienne. L'un des plus importants réservoirs est celui de Chioggia Mare, situé à environ 10 km au large du littoral vénitien, à une profondeur de 1000 à 1400 m. La production de gaz prévue pour ce gisement laisse envisager un impact sur la stabilité du trait de côte, avec une

Limited impact of beach nourishment on macrofaunal recruitment/settlement in a site of community interest in coastal area of the Adriatic Sea (Mediterranean Sea).

Science.gov (United States)

Danovaro, Roberto; Nepote, Ettore; Martire, Marco Lo; Ciotti, Claudia; De Grandis, Gianluca; Corinaldesi, Cinzia; Carugati, Laura; Cerrano, Carlo; Pica, Daniela; Di Camillo, Cristina Gioia; Dell'Anno, Antonio

2018-03-01

Beach nourishment is a widely utilized solution to counteract the erosion of shorelines, and there is an active discussion on its possible consequences on coastal marine assemblages. We investigated the impact caused by a small-scale beach nourishment carried out in the Western Adriatic Sea on macrofaunal recruitment and post-settlement events. Artificial substrates were deployed in proximity of nourished and non-manipulated beaches and turbidity and sedimentation rates were measured. Our results indicate that sedimentation rates in the impacted site showed a different temporal change compared to the control sites, suggesting potential modifications due to the beach nourishment. The impact site was characterized by subtle changes in terms of polychaete abundance and community structure when compared to controls, possibly due to beach nourishment, although the role of other factors cannot be ruled out. We conclude that small-scale beach nourishments appear to be an eco-sustainable approach to contrast coastal erosion. Copyright © 2018. Published by Elsevier Ltd.

Radioactivity of fission products in cistern waters along the Croatian coast of the Adriatic Sea

International Nuclear Information System (INIS)

Franic, Z.; Marovic, G.

1997-01-01

Measurements of radioactive contamination of water samples from cisterns collecting rainwater from roofs etc. with fission products have been carried out along the Croatian coast of the Adriatic Sea since 1968. An exponential decline of radioactivity followed the nuclear moratorium.After the nuclear accident at Chernobyl, higher levels of 137 Cs and 90 Sr were detected again, cistern waters being the only environmental samples in Croatia in which elevated 90 Sr activities persisted for several years. For the pre-Chernobyl period, the mean residence time of 90 Sr in cistern waters being order of magnitude several years was similar to that calculated for fallout.Contrary, for the post-Chernobyl time, S r mean residence time was calculated to be considerably shorter, reflecting the tropospheric mean residence time.Therefore, the pre-Chernobyl) and the post-Chernobyl mean residence times of 90 Sr in cistern waters reflect the mechanism by which strontium was released to the atmosphere. The annual dose for the critical adult population received from 90 Sr, 137 Cs and 90 Cs by drinking cistern water was estimated to be a few per cent of the dose from natural background radiation. (authors)

The modest seismicity of the northern Red Sea rift

Science.gov (United States)

Mitchell, Neil C.; Stewart, Ian C. F.

2018-05-01

Inferring tectonic movements from earthquakes (`seismotectonics') relies on earthquakes faithfully recording tectonic motions. In the northern half of the Red Sea, however, events of magnitude 5.0 and above are almost entirely absent from global catalogues, even though GPS and other plate motion data suggest that the basin is actively rifting at ˜10 mm yr-1. Seismic moments computed here from event magnitudes contributed to the International Seismology Centre (ISC) suggest that the moment release rate is more than an order of magnitude smaller than for the southern Red Sea and for the Southwest Indian Ridge (SWIR), which is spreading at a comparable rate to the central Red Sea and is more remote from recording stations. A smaller moment release rate in the northern Red Sea might be anticipated from its smaller spreading rate, but seismic coupling coefficients, which account for spreading rate variations, are also one order of magnitude smaller than for the other two areas. We explore potential explanations for this apparently reduced seismicity. The northern Red Sea is almost continuously covered with thick evaporites and overlying Plio-Pleistocene sediments. These deposits may have reduced the thickness of the seismogenic layer, for example, by elevating lithosphere temperatures by a thermal blanketing effect or by leading to excess pore fluid pressures that reduce effective stress. The presence of subdued seismicity here implies that tectonic movements can in places be poorly recorded by earthquake data and requires that alternative data be sought when investigating the active tectonics of sedimented rifts in particular.

Detecting human presence at the border of the Northeastern Italian Pre-Alps. 14C dating at Rio Secco cave as expression of the first Gravettian and the late mousterian in the Northern Adriatic Region.

Science.gov (United States)

Talamo, Sahra; Peresani, Marco; Romandini, Matteo; Duches, Rossella; Jéquier, Camille; Nannini, Nicola; Pastoors, Andreas; Picin, Andrea; Vaquero, Manuel; Weniger, Gerd-Christian; Hublin, Jean-Jacques

2014-01-01

In the northern Adriatic regions, which include the Venetian region and the Dalmatian coast, late Neanderthal settlements are recorded in few sites and even more ephemeral are remains of the Mid-Upper Palaeolithic occupations. A contribution to reconstruct the human presence during this time range has been produced from a recently investigated cave, Rio Secco, located in the northern Adriatic region at the foot of the Carnic Pre-Alps. Chronometric data make Rio Secco a key site in the context of recording occupation by late Neanderthals and regarding the diffusion of the Mid-Upper Palaeolithic culture in a particular district at the border of the alpine region. As for the Gravettian, its diffusion in Italy is a subject of on-going research and the aim of this paper is to provide new information on the timing of this process in Italy. In the southern end of the Peninsula the first occupation dates to around 28,000 14C BP, whereas our results on Gravettian layer range from 29,390 to 28,995 14C years BP. At the present state of knowledge, the emergence of the Gravettian in eastern Italy is contemporaneous with several sites in Central Europe and the chronological dates support the hypothesis that the Swabian Gravettian probably dispersed from eastern Austria.

Sediment Resuspension and Transport During Bora in the Western Adriatic Coastal Current

Science.gov (United States)

Mullenbach, B. L.; Geyer, W. R.; Sherwood, C. R.

2004-12-01

The Western Adriatic Coastal Current (WACC) is an important agent for along-shelf transport of sediment and fresh water in the western Adriatic Sea. The WACC is driven by a combination of buoyancy forcing from the Po River (northern Adriatic) and wind forcing from northeasterly Bora winds. The large seasonal pulse of freshwater (during the winter) from the Po River influences WACC strength; however, preliminary results from current measurements and model runs indicate that the WACC responds quickly and strongly to Bora wind events, with a strengthening of the current moving southward. Along-margin sediment transport to the south is significantly increased as a result of Bora wind events, presumably because of enhanced wave resuspension and WACC velocity. Elevated sediment fluxes have been observed in both the upper water column (i.e., core of the WACC) and bottom boundary layer (BBL) during these events, which suggests that wind-driven currents may be coupled with the near-bottom transport. This study addresses the interaction of the WACC with the BBL and the impact of this interaction on sediment transport in the western Adriatic. Two benthic tripods were deployed from November 2002 to June 2003 on an across-shelf transect near the Chienti River (at 10 and 20-m water depth), in the region where WACC begins to intensify (200 km south of Po River). Continuous measurements of suspended sediment concentration and current velocity were recorded in the upper-water column and BBL to document sediment transport events. A time series of sediment fluxes and shear velocities (from currents only, u*c; from waves and currents, u*wc) were calculated from these data. Results show that suspended sediment concentrations near the seabed (few cmab) during Bora wind events are strongly correlated with u*wc, which supports a previous hypothesis that wave resuspension (rather than direct fluvial input) is responsible for much of the suspended sediment available for transport southward

Northern and Southern European Traffic Flow Land Segment Analysis as Part of the Redirection Justification

Directory of Open Access Journals (Sweden)

SiniŁa Vilke

2017-12-01

Full Text Available Natural geotraffic flows act as one of the most important factors directly affecting redirections of the world transportation routes. In terms of door-to-door multimodal transport chain, several routes from Far East toward European destinations exist, with Northern European route acting as prevailing one. The proposed paper elaborates possibilities of redirection of the traffic flow by directing cargoes to an alternative route through the Adriatic Sea. The aim is to justify realisation of mentioned possibility in terms of land transportation segment analysis, i.e. by analysing cargo transportation from ports to final destinations in Central Europe, placed in natural gravitational hinterland of ports of Northern Adriatic Port Association (NAPA. Geo-traffic and logistics’ analyses of NAPA ports are presented in the paper. Container traffic and its trend as compared with Northern European ports are analysed. The development plans of inland connections are presented in function of justification of the traffic flow redirection. A model for the selection and evaluation of the optimal container transport route by using the multiple criteria analysis (MCA has been introduced and developed. The model was applied for the selection of the representative service connecting Far East (origin and the central Europe (destination by detailed analysis of the land transportation segment. The PROMETHEE method was used for the model testing and evaluation. Summarised results are presented and discussed tending to confirmation of the traffic flow redirection justification.

New constraints on the crustal structure beneath northern Tyrrhenian Sea

Science.gov (United States)

Levin, V. L.; Park, J. J.

2009-12-01

We present new seismological data on the seismic structure beneath the Tyrrhenian Sea between Corsica and the coast of Italy. Teleseismic receiver functions from two Tyrrhenian islands (Elba and Gorgona) identify clear P-to-S mode-converted waves from two distinct interfaces, at ~20 and ~45 km depth. Both interfaces are characterized by an increase of seismic wavespeed with depth. Using a summation of direct and multiply-reflected body waves within the P wave coda we estimate the mean ratio of compressional and shear wave speeds above the 45 km interface to be 1.75-1.80. Using reflectivity computations in 1D layered models we develop a model of seismic wavespeed distribution that yields synthetic seismograms very similar to those observed. We apply a Ps-multiple summation procedure to the synthetic waveforms to further verify the match between observed and predicted wavefields. The lower layer of our model, between 20 and 45 km, has Vp ~ 7.5 km/sec, a value that can be ascribed to either very fast crustal rocks or very slow upper mantle rocks. The Vp/Vs ratio is ~1.8 in this intermediate layer. On the basis of a well-constrained downward increase in seismic wave speed beneath this second layer, we interpret it as the magmatically reworked lower crust, a lithology that has been proposed to explain high-Vp layers in the crustal roots of island-arc terranes and volcanically altered continental margins, as well as lower-crustal high-Vp features sometimes seen beneath continental rifts. The presence of a thick layer of high-Vp, but crustal, lithology beneath the Tyrrhenian Sea differs considerably from previous estimates that interpreted the interface at ~20 km as the Moho. Our new interpretation obviates a need for a crustal thickness change of over 20 km at the crest of the Apennines orogen. We propose an alteration in the properties of the lower crust instead. We argue that ongoing convergent subduction of the Adriatic lithospehre is not required beneath northern

Differences and similarities of the Eocene to recent Sphaerogypsina tests collected from the Pannonian basin to the Adriatic Sea

Science.gov (United States)

Drobne, Katica; Ćosović, Vlasta; Čretnik, Janko; Turk, Janez; Briguglio, Antonino; Rögl, Fred; Praprotnik, Anton

2017-04-01

With a new series of shots in the X-ray tomographic techniques (CT), the study of fossil (Eocene and Miocene) and recent tests of Sphaerogypsina globulus (Reuss, 1848) sensu lato, sampled in the Adriatic Sea and adjacent coastal areas, have continued. The Eocene, Lutetian samples collected at the NW margin of the Central Neotethys (Benkovac) contain tests up to 2 mm in diameters, while specimens found in Priabonian deposits from the southern outskirts of the Eastern Alps (Šuštarica, Ravna Gora) and in the central Pannonian basin (Eger) are smaller, with diameters of 1.2 mm. In the Oligocene, Rupelian, sediments, deposited in the Slovenian corridor, area south of the E. Alps, known as representing transition between recessing Neotethys and emerging Pannonian Sea, (Gornji grad, Nova Štifta), foraminiferal tests are of 1.1 mm in diameter. Globular tests of Miocene, Badenian, specimens (Nussdorf, north of the E. Alps), originally described as bryozoan Ceriopora globulus by Reuss 1848, attained 1.2 mm in diameter. Comparison of tests diameters shows that Middle Eocene sphaerogypsinids had the largest tests among fossil taxa, implying that warm temperatures suited them a lot. The Oligocene tests, were smaller and the trend of decreasing in size persisted in the Miocene. Recent tests, although collected over decades from different places in the Adriatic Sea, just recently have been systematically sampled at Pakleni Is. (Hvar), Kornati archipelago and Mali Čutin Is., and studied.The tests, with diameters ranging from 0.3 to 1.0 mm (an average of 0.6 to 0.8 mm), are very small in comparison with fossil forms. The life habitats, as type of substrate, light (sunny vs. shadowed areas) have been investigated, revealing that sphaerogypsinids prefer to live at water depth up to 50 - 60 m. Special attention is payed to find live specimens, which would provide the basis for DNA analysis. The application of micro- tomography contributed significantly in studying test internal

Fluviokarst and classical karst: Examples from the Dinarics (Krk Island, Northern Adriatic, Croatia)

Science.gov (United States)

Benac, Čedomir; Juračić, Mladen; Matičec, Dubravko; Ružić, Igor; Pikelj, Kristina

2013-02-01

In order to contribute to the debate on the role of fluvial erosion in the shaping of karst, two nearby areas with different karstic landscapes were compared. Areas A and B are located relatively close to each other on the southern side of the Krk Island (Adriatic Sea, Croatia). Both areas are composed of similar limestone with a very high CaCO3 content. Area A is a typical doline or polygonal type ("classical") of karst with numerous dolines (up to 57/km2) covered with terra rossa (red soil) and Mediterranean maquis shrubland. Dolines are located in zones which correspond to the strike of the main geological structures. Dry karstic valleys are visible only on gently inclined coastal slopes bordering the karstic plateau. In contrast, area B is typical of a bare karst landscape with a strong (palaeo)fluvial imprint. The dolines are absent, and the bedrock is only sporadically covered with terra rossa. Palaeogene marls have been observed in a few elongated depressions and in the coastal zone of area B. Along steep coastal slopes, valleys (up to 460 m/km2) are cut into the carbonates. The traces of episodic surface flows are visible in some of these valleys, in contrast to the valleys in area A. Remnants of a disrupted ancient fluvial network are clearly visible on the elevated karstic plateau in area B. Differences in the recent morphology are attributed mainly to varying thicknesses of the Palaeogene impermeable marly cover, and the intensity of tectonics in the two areas.

Studies in living and fossil foraminifers from seasonally productive regions

NARCIS (Netherlands)

Barmawidjaja, D.M.

1991-01-01

Paleoecological and paleoenvironmental analysis of benthic and planktonic foraminiferal associations from sediments from the northern Adriatic Sea, the Kau Basin (Halmahera) and the Molucca Sea shed new light on the way in which various environmental factors influence foraminiferal distribution

Uncinariasis in northern fur seal and California sea lion pups from California.

Science.gov (United States)

Lyons, E T; DeLong, R L; Melin, S R; Tolliver, S C

1997-10-01

Northern fur seal (Callorhinus ursinus) (n = 25) and California sea lion (Zalophus californianus) (n = 53) pups, found dead on rookeries on San Miguel Island (California, USA), were examined for adult Uncinaria spp. Prevalence of these nematodes was 96% in fur seal pups and 100% in sea lion pups. Mean intensity of Uncinaria spp. per infected pup was 643 in fur seals and 1,284 in sea lions. Eggs of Uncinaria spp. from dead sea lion pups underwent embryonation in an incubator; development to the free-living third stage larva occurred within the egg. This study provided some specific information on hookworm infections in northern fur seal and California sea lion pups on San Miguel Island. High prevalence rate of Uncinaria spp. in both species of pinnipeds was documented and much higher numbers (2X) of hookworms were present in sea lion than fur seal pups.

Age and growth of Crystallogobius linearis (von Düben, 1845 (Teleostei: Gobiidae from the Adriatic Sea

Directory of Open Access Journals (Sweden)

M. La Mesa

2001-12-01

Full Text Available Age and growth of the crystal goby Crystallogobius linearis (von Düben, 1845 were investigated by means of daily growth increment counts on the sagittal otoliths. Samples of C. linearis, obtained as by-catch of the Aphia minuta fishery, were collected in a coastal area of the central Adriatic Sea between March and September 1996. Otolith age-readings were carried out on 167 specimens, ranged from 14 to 41 mm of total length, and indicated that the population was composed of individuals from two to seven months old. Growth of both males and females appeared practically linear over the whole size range studied, although in females a slight decrease in growth rate of older specimens was observed. Furthermore, the hatch date distribution of C. linearis, obtained by the backcalculation of the ageing data, indicated a long breeding season of at least eight months. The results of this study indicated that, as reported from literature for most nektonic gobies, the crystal goby is also characterised by a short life span, during which a high reproductive effort is displayed throughout a long breeding season.

Slow Warming of the Northern South China Sea during the Last Deglaciation

Directory of Open Access Journals (Sweden)

Tomoya Shintani

2008-01-01

Full Text Available We have generated a record of alkenone sea surface temperatures (SSTs during the last 28000 years from Core MD97-2146 for the northern South China Sea (SCS. The SST record showed a typical pattern for change in the northern SCS SST. The SST during the LGM was ~25 C, this decreased to ~24 C to 17 ka, increased to ~25.5 C to 14.5 ka, decreased again to ~24.5 C to 11.8 ka, increased gradually to ~27 C to 6 ka, and then increased more gradually to reach ~27.5 C at present. The SST difference ( SSTNSCS = SSTMD97-2146 - SSTMD97-2141 between Cores MD97-2146 (the northern SCS; this study and MD97-2141 (the Sulu Sea; Rosenthal et al. 2003 was used to characterize the SST changes in the northern SCS relative to changes in the adjacent WTPregion. The SSTNSCS decreased from 21 to 11.8 ka and increased after 11.8 ka, indicating slower warming of the northern SCS during the last deglaciation than that of the adjacent western tropical Pacific region.We infer that the slow warming of the northern SCS was principally a result of stronger winter monsoon during the last deglaciation and early Holocene. In addition, the cool water inflow through the Taiwan Strait after 13 ka and the warm water inflow through the Sunda Shelf after 11 ka could influence the SST in the northern SCS.

Detecting human presence at the border of the Northeastern Italian Pre-Alps. 14C dating at Rio Secco cave as expression of the first Gravettian and the late mousterian in the Northern Adriatic Region.

Directory of Open Access Journals (Sweden)

Sahra Talamo

Full Text Available In the northern Adriatic regions, which include the Venetian region and the Dalmatian coast, late Neanderthal settlements are recorded in few sites and even more ephemeral are remains of the Mid-Upper Palaeolithic occupations. A contribution to reconstruct the human presence during this time range has been produced from a recently investigated cave, Rio Secco, located in the northern Adriatic region at the foot of the Carnic Pre-Alps. Chronometric data make Rio Secco a key site in the context of recording occupation by late Neanderthals and regarding the diffusion of the Mid-Upper Palaeolithic culture in a particular district at the border of the alpine region. As for the Gravettian, its diffusion in Italy is a subject of on-going research and the aim of this paper is to provide new information on the timing of this process in Italy. In the southern end of the Peninsula the first occupation dates to around 28,000 14C BP, whereas our results on Gravettian layer range from 29,390 to 28,995 14C years BP. At the present state of knowledge, the emergence of the Gravettian in eastern Italy is contemporaneous with several sites in Central Europe and the chronological dates support the hypothesis that the Swabian Gravettian probably dispersed from eastern Austria.

Towards the Adriatic meteotsunami early warning system: modelling strategy and validation

Science.gov (United States)

Denamiel, Clea; Šepić, Jadranka; Vilibić, Ivica

2017-04-01

Destructive meteotsunamis are known to occur along the eastern Adriatic coastal areas and islands (Vilibić and Šepić, 2009). The temporal lag between the offshore generation of meteotsunamis due to specific atmospheric conditions and the arrival of a dangerous nearshore propagating wave at known locations is of the order of tens of minutes to a couple of hours. In order to reduce the coastal risk for the coastal communities, an early warning system must rely on the ability to detect these extreme storms offshore with in-situ measurements and to predict the hydrodynamic response nearshore via numerical models within this short time lag. However, the numerical modelling of meteotsunamis requires both temporal and spatial high-resolution atmospheric and ocean models which are highly demanding concerning time and computer resources. Furthermore, both a multi-model approach and an ensemble modelling strategy should be used to better forecast the distribution of the nearshore impact of meteotsunamis. The modelling strategy used in this study thus rely on the development of an operational atmosphere-ocean model of the Adriatic Sea at 1km spatial resolution based on the state-of-the-art fully coupled COAWST model (Warner et al., 2010). The model allows for generation of meteotsunamis offshore, while various high-resolution (up to 5m) nearshore hydrodynamic models (such as ADCIRC - Luettich and Westerink, 1991; SELFE - Zhang et al., 2008 and GeoClaw - LeVeque, 2012) are setup to properly reproduce meteotsunami dynamics of the entire Croatian coastal areas, which are characterized by a great number of islands, channels and bays. The implementation and validation of each component of this modelling system is first undertaken for the well documented meteotsunami event (Šepić et al., 2016), which was recorded along the Croatian Adriatic coast on the 25th and the 26th of June 2014. The validation of the modelling strategy as well as the model results is presented and

Water resources vulnerability assessment in the Adriatic Sea region: the case of Corfu Island.

Science.gov (United States)

Kanakoudis, Vasilis; Tsitsifli, Stavroula; Papadopoulou, Anastasia; Cencur Curk, Barbara; Karleusa, Barbara

2017-09-01

Cross-border water resources management and protection is a complicated task to achieve, lacking a common methodological framework. Especially in the Adriatic region, water used for drinking water supply purposes pass from many different countries, turning its management into a hard task to achieve. During the DRINKADRIA project, a common methodological framework has been developed, for efficient and effective cross-border water supply and resources management, taking into consideration different resources types (surface and groundwater) emphasizing in drinking water supply intake. The common methodology for water resources management is based on four pillars: climate characteristics and climate change, water resources availability, quality, and security. The present paper assesses both present and future vulnerability of water resources in the Adriatic region, with special focus on Corfu Island, Greece. The results showed that climate change is expected to impact negatively on water resources availability while at the same time, water demand is expected to increase. Water quality problems will be intensified especially due to land use changes and salt water intrusion. The analysis identified areas where water resources are more vulnerable, allowing decision makers develop management strategies.

Economic vulnerability to sea-level rise along the northern U.S. Gulf Coast

Science.gov (United States)

Thatcher, Cindy A.; Brock, John C.; Pendleton, Elizabeth A.

2013-01-01

The northern Gulf of Mexico coast of the United States has been identified as highly vulnerable to sea-level rise, based on a combination of physical and societal factors. Vulnerability of human populations and infrastructure to projected increases in sea level is a critical area of uncertainty for communities in the extremely low-lying and flat northern gulf coastal zone. A rapidly growing population along some parts of the northern Gulf of Mexico coastline is further increasing the potential societal and economic impacts of projected sea-level rise in the region, where observed relative rise rates range from 0.75 to 9.95 mm per year on the Gulf coasts of Texas, Louisiana, Mississippi, Alabama, and Florida. A 1-m elevation threshold was chosen as an inclusive designation of the coastal zone vulnerable to relative sea-level rise, because of uncertainty associated with sea-level rise projections. This study applies a Coastal Economic Vulnerability Index (CEVI) to the northern Gulf of Mexico region, which includes both physical and economic factors that contribute to societal risk of impacts from rising sea level. The economic variables incorporated in the CEVI include human population, urban land cover, economic value of key types of infrastructure, and residential and commercial building values. The variables are standardized and combined to produce a quantitative index value for each 1-km coastal segment, highlighting areas where human populations and the built environment are most at risk. This information can be used by coastal managers as they allocate limited resources for ecosystem restoration, beach nourishment, and coastal-protection infrastructure. The study indicates a large amount of variability in index values along the northern Gulf of Mexico coastline, and highlights areas where long-term planning to enhance resiliency is particularly needed.

Status of breeding seabirds on the Northern Islands of the Red Sea, Saudi Arabia.

Science.gov (United States)

Shobrak, Mohammed Y; Aloufi, Abdulhadi A

2014-07-01

We undertook breeding surveys between 2010 and 2011 to assess the status of breeding birds on 16 islands in the northern Saudi Arabia. Sixteen bird species were found breeding at three different seasons; i.e. winter (Osprey), spring (Caspian and Saunder's Terns), and summer (Lesser Crested, White-cheeked, Bridled Terns). It is postulated that food availability is an important factor influencing the breeding of seabirds in the northern Saudi Arabian Red Sea. Several species laid eggs earlier in northern parts of the Red Sea than in southern parts. The predicted increases in temperatures (Ta ) could have a negative effect on species survival in the future, especially on those whose nests that are in the open. Finally, disturbance, predation and egg collection were probably the main immediate threats affecting the breeding seabird species in the northern Red Sea.

"Pittura Romeica" in Italy: Artistic transfers across the Adriatic sea (18th - 19th centuries

Directory of Open Access Journals (Sweden)

Eugenia Drakopoulou

2017-02-01

Full Text Available The complex historical reality of the Adriatic region, an area located even today on the borderline between East and West, is reflected in the works of religious painting and in the painters’ geographical movements. The art of Orthodox regions was mainly influenced by Venice, but also by the rest of Italy, and, as a result, a unique art emerged in the Ionian Islands, which remained under Venetian control until the end of the eighteenth century. In the course of the eighteenth century, political and economic conditions contributed to the growth of the Orthodox communities in Italy. Their members were interested in the art of the country where they lived and prospered, but they simultaneously wished to preserve the “pittura romeica” in the decorations of churches and in the icons used for their personal worship. From Naples to the cosmopolitan Trieste, Orthodox painters, coming mainly from the Ionian Islands, produced artworks which were adapted to the new surroundings, thereby making the Adriatic region once again a privileged area for cultural exchanges.

Near-surface wind pattern in regional climate projections over the broader Adriatic region

Science.gov (United States)

Belušić, Andreina; Telišman Prtenjak, Maja; Güttler, Ivan; Ban, Nikolina; Leutwyler, David; Schär, Christoph

2017-04-01

The Adriatic region is characterized by the complex coastline, strong topographic gradients and specific wind regimes. This represents excellent test area for the latest generation of the regional climate models (RCMs) applied over the European domain. The most famous wind along the Adriatic coast is bora, which due to its strength, has a strong impact on all types of human activities in the Adriatic region. The typical bora wind is a severe gusty downslope flow perpendicular to the mountains. Besides bora, in the Adriatic region, typical winds are sirocco (mostly during the wintertime) and sea/land breezes (dominantly in the warm part of the year) as a part of the regional Mediterranean wind system. Thus, it is substantial to determine future changes in the wind filed characteristics (e.g., changes in strength and frequencies). The first step was the evaluation of a suite of ten EURO- and MED-CORDEX models (at 50 km and 12.5 km resolution), and two additional high resolution models from the Swiss Federal Institute of Technology in Zürich (ETHZ, at 12.5 km and 2.2. km resolution) in the present climate. These results provided a basis for the next step where wind field features, in an ensemble of RCMs forced by global climate models (GCMs) in historical and future runs are examined. Our aim is to determine the influence of the particular combination of RCMs and GCMs, horizontal resolution and emission scenario on the future changes in the near-surface wind field. The analysis reveals strong sensitivity of the simulated wind flow and its statistics to both season and location analyzed, to the horizontal resolution of the RCM and on the choice of the particular GCM that provides boundary conditions.

Diversity of rare and abundant bacteria in surface waters of the Southern Adriatic Sea.

Science.gov (United States)

Quero, Grazia Marina; Luna, Gian Marco

2014-10-01

Bacteria are fundamental players in the functioning of the ocean, yet relatively little is known about the diversity of bacterioplankton assemblages and the factors shaping their spatial distribution. We investigated the diversity and community composition of bacterioplankton in surface waters of the Southern Adriatic sub-basin (SAd) in the Mediterranean Sea, across an environmental gradient from coastal to offshore stations. Bacterioplankton diversity was investigated using a whole-assemblage genetic fingerprinting technique (Automated Ribosomal Intergenic Spacer Analysis, ARISA) coupled with 16S rDNA amplicon pyrosequencing. The main physico-chemical variables showed clear differences between coastal and offshore stations, with the latter displaying generally higher temperature, salinity and oxygen content. Bacterioplankton richness was higher in coastal than offshore waters. Bacterial community composition (BCC) differed significantly between coastal and offshore waters, and appeared to be influenced by temperature (explaining up to 30% of variance) and by the trophic state. Pyrosequencing evidenced dominance of Alphaproteobacteria (SAR11 cluster), uncultured Gammaproteobacteria (Rhodobacteraceae) and Cyanobacteria (Synechococcus). Members of the Bacteroidetes phylum were also abundant, and accounted for 25% in the station characterized by the higher organic carbon availability. Bacterioplankton assemblages included a few dominant taxa and a very large proportion (85%) of rare (diversity, particularly evident at the level of the rare taxa, suggests to direct future investigations toward larger spatial or temporal scales, to better understand the role of bacterioplankton in the ecosystem functioning and the biogeochemistry of the basin. Copyright © 2014 Elsevier B.V. All rights reserved.

SURVEY ON V. CHOLERAE, V. VULNIFICUS AND V. PARAHAEMOLYTICUS IN BIVALVE MOLLUSCS OF THE ADRIATIC SEA AND PROPOSAL OF AN ANALYTICAL PROTOCOL

Directory of Open Access Journals (Sweden)

M.L. Valeri

2009-06-01

Full Text Available Bivalve molluscs from Adriatic sea were analyzed for V. parahaemolyticus, V. cholerae e V. vulnificus presence. The isolates on TCBS Agar and m-CPC Agar were selected on the basis of a new biochemical screening, that showed a good performance, because among 2344 strains from primary culture only 237 (10% were presumptively assigned to the species of interest. The PCR analyses was performed for the target genes toxR hlyA, ctxA, tcpI (V. cholerae, toxR, tl, tdh, trh (V. parahaemolyticus, vvhA and viuB (V. vulnificus. Among the 9 strains confirmed to belong to V. parahaemolyticus specie, 6 were sucrose positive. On 215 samples of molluscs only 5 resulted positive for V. parahaemolyticus being toxR+, tl+, although non pathogenic (tdh-, trh-, and none for V. cholerae e V. vulnificus.

The addition of hydrodynamic variables to predictive cold water coral habitat modeling: The Bari Canyon case-study, southwestern Adriatic Sea

Science.gov (United States)

Foglini, Federica; Bargain, Annaëlle; Angeletti, Lorenzo; Bonaldo, Davide; Carniel, Sandro; Taviani, Marco

2017-04-01

Predictive habitat modeling is gaining momentum because of its usefulness to recognize potential distributional patterns of ecosystems thus facilitating their proper governance when required, as it is for instance the case of the Marine Strategy Framework Directive (MSFD). This holds particularly true for the deep-sea in front of its overwhelming areal extent on a global scale and intrinsic technological difficulties (with related costs) for its direct exploration. Cold Water Corals (CWC) is one emblematic, virtually cosmopolitan, ecosystem in the deep, that is under international attention because of its multifaceted ecological importance. CWC is currently represented in the Mediterranean basin by habitats engineered by the arborescent scleractinians Madrepora oculata and Lophelia pertusa associated with a number of other benthic invertebrates. One major CWC hotspot located on the southwestern Adriatic margin, the Bari Canyon cold water coral province, has been targeted for producing habitat suitability maps. Initially the evaluation of the theoretical distribution of CWC in this area has been based upon visual observations, mainly extracted from geo-referenced underwater ROV imagery, coupled with the eco-geographic information derived from bathymetry. This approach relies upon the compilation and comparison of presence-only models (MaxEnt and ENFA), but also presence-absence model (GLMs). However, the pivotal role played by oceanographic factors has been soon added in order to achieve more robust predictive models. In fact, the Bari Canyon CWC province is situated on the main path of the North Adriatic Dense Water cascading, and hypothesized to be sensitive to hydrological factors. Accordingly, the statistical models to assess potential habitat extent have been implemented using hydrodynamic fields provided by ROMS for ocean currents, coupled with SWAN within the COAWST modelling system to account for wave-current interactions. The integration of results is

Spatially explicit risk approach for multi-hazard assessment and management in marine environment: The case study of the Adriatic Sea.

Science.gov (United States)

Furlan, Elisa; Torresan, Silvia; Critto, Andrea; Marcomini, Antonio

2018-03-15

In the last few decades the health of marine ecosystems has been progressively endangered by the anthropogenic presence. Natural and human-made pressures, as well as climate change effects, are posing increasing threats on marine areas, triggering alteration of biological, chemical and physical processes. Planning of marine areas has become a challenge for decision makers involved in the design of sustainable management options. In order to address threats posed by climate drivers in combination with local to regional anthropogenic pressures affecting marine ecosystems and activities, a multi-hazard assessment methodology was developed and applied to the Adriatic Sea for the reference scenario 2000-2015. Through a four-stages process based on the consecutive analysis of hazard, exposure, vulnerability and risk the methodology allows a semi-quantitative evaluation of the relative risk from anthropogenic and natural sources to multiple endpoints, thus supporting the identification and ranking of areas and targets more likely to be at risk. Resulting output showed that the higher relative hazard scores are linked to exogenic pressures (e.g. sea surface temperature variation) while the lower ones resulted from endogenic and more localized stressors (e.g. abrasion, nutrient input). Relatively very high scores were observed for vulnerability over the whole case study for almost all the considered pressures, showing seagrasses meadows, maërl and coral beds as the most susceptible targets. The approach outlined in this study provides planners and decision makers a quick-screening tool to evaluate progress towards attaining a good environmental status and to identify marine areas where management actions and adaptation strategies would be best targeted. Moreover, by focusing on risks induced by land-based drivers, resulting output can support the design of infrastructures for reducing pressures on the sea, contributing to improve the land-sea interface management

Synecology of Cutandia maritima (L. Barbey, a rare psammophytic species along the Montenegrin Coast (East Adriatic Coast

Directory of Open Access Journals (Sweden)

Stešević Danijela

2017-12-01

Full Text Available Cutandia maritima is a circum-Mediterranean species that inhabits sandy dunes along the coast line. It is fairly frequent on the western Adriatic coast but fairly rare and possibly even non-native in the east. In Croatia, it was discovered in 1990 in Crnika Bay on the island of Rab, which was considered until 2005 to be the only site on the eastern Adriatic coast from the Gulf of Trieste in the north to Corfu in the south. In 2009, the species was briefly reported for Velika plaža (Long Beach in Ulcinj (Montenegro but without details about the habitat type and synecology. The aim of this paper is thus to provide a deeper insight into the ecology and synecology of C. maritima in the eastern Adriatic part of the distribution area. On Velika plaža in Ulcinj, the species was found along the whole sea-inland gradient of sand dunes, in various types of vegetation: [1210] - annual vegetation of drift lines, [2110] - embryonic shifting dunes, [2120] - shifting dunes with Ammophila arenaria (white dunes, [2220] - dunes with Euphorbia terracina, [2130*] - fixed coastal dunes with herbaceous vegetation (grey dunes, and also [2190] - humid dune slacks.

Sources of the deep water masses in the northern Red Sea

OpenAIRE

Said, M.A.

1998-01-01

The hydrographic structure of the northern Red Sea indicated that, the surface waters of temperature around 22°C, salinity of 40.1OO%o and dt = 28.1 might sink to depths between 400-500 m by convective overturn, contributing to the formation of the mid-deep Red Sea waters. Below the 500 db depth down to the bottom the water column is stable. The geostrophic circulation clearly indicated an inflow of water from the Red Sea towards NNW, along the main axis of the sea. Arriving at the nort...

Seismic investigation of an ocean-continent transition zone in the northern South China Sea

Science.gov (United States)

Zhu, J.; Qiu, X.; Xu, H.; Zhan, W.; Sun, Z.

2011-12-01

Rifted continental margins and basins are mainly formed by the lithospheric extension. Thined lithosphere of passive continental margins results in decompression melt of magma and created oceanic crust and thined ocean-continent transition (OCT) zone. Two refraction profiles used ocean bottom seismometers deployed in the broad continental shelf and three multi-channel seismic reflection lines in the northern South China Sea, acquired by the ship "Shiyan 2" of the South China Sea Institute of Oceanology, Chinese Academy of Sciences in 2010, are processed and interpreted in this study. Seismic reflection lines cut through the Dongsha rise, Zhu-1 and Zhu-2 depression within a Tertiary basin, Pear River Mouth basin (called as Zhujiangkou basin). These tectonic features are clear imaged in the seismic reflection records. Numerous normal faults, cutted through the basement and related to the stretch of the northern South China Sea margin, are imaged and interpreted. Reflection characteristics of the ocean-continent transition (OCT) zone are summaried and outlined. The COT zone is mainly divided into the northern syn-rift subsidence zone, central volcano or buried volcano uplift zone and tilt faulted block near the South Chia Sea basin. Compared to the previous seismic reflection data and refraction velocity models, the segmentation range of the OCT zone is outlined, from width of about 225 km in the northeastern South China Sea , of 160 km in the central to of 110 km in the north-central South China Sea. Based on the epicenter distribution of sporadic and large than 6 magnitude earthquakes, it suggests the OCT zone in the northern South China Sea at present is still an active seismic zone.

BACTERIOLOGICAL PROPERTIES OF MARINE WATER IN ADRIATIC FISH FARMS: ENUMERATION OF HETEROTROPHIC BACTERIA

Directory of Open Access Journals (Sweden)

Emin Teskeredžić

2012-12-01

Full Text Available Aquaculture is currently one of the fastest growing food production sectors in the world. Increase in nutrients and organic wastes lead to general deterioration of water quality. The problem of water quality is associated with both physical and chemical factors, as well as microbiological water quality. Heterotrophic bacteria play an important role in the process of decomposition of organic matter in water environment and indicate eutrophication process. Here we present our experience and knowledge on bacterial properties of marine water in the Adriatic fish farms with European sea bass (Dicentrarchus labrax L., 1758, with an emphasis on enumeration of heterotrophic bacteria in marine water. We applied two temperatures of incubation, as well as two methods for enumeration of heterotrophic bacteria: substrate SimPlate® test and spread plate method on conventional artificial media (Marine agar and Tryptic Soy agar with added NaCl. The results of analysis of bacteriological properties of marine water in the Adriatic fish farms showed that enumeration of heterotrophic bacteria in marine water depends on the applied incubation temperature and media for enumeration. At the same time, the incubation temperature of 22C favours more intense growth of marine heterotrophic bacteria, whereas a SimPlate test gives higher values of heterotrophic bacteria. Volatile values of heterotrophic bacteria during this research indicate a possible deterioration of microbiological water quality in the Adriatic fish farms and a need for regular monitoring of marine water quality.

Microfaunal analysis of late Quaternary deposits of the northern Bering Sea.

Science.gov (United States)

McDougall, K.

1982-01-01

Holocene microfaunal associations and distribution patterns define three inner-shelf (1-20m) biofacies in Norton Sound, northern Bering Sea. The Holocene facies relations are the basis for interpreting early Holocene and late Pleistocene environmental conditions in the NE Bering Sea area. Norton Sound cores provide evidence of two marine transgressions and a varying river input.-from Author

Estimation of potential distribution of gas hydrate in the northern South China Sea

Science.gov (United States)

Wang, Chunjuan; Du, Dewen; Zhu, Zhiwei; Liu, Yonggang; Yan, Shijuan; Yang, Gang

2010-05-01

Gas hydrate research has significant importance for securing world energy resources, and has the potential to produce considerable economic benefits. Previous studies have shown that the South China Sea is an area that harbors gas hydrates. However, there is a lack of systematic investigations and understanding on the distribution of gas hydrate throughout the region. In this paper, we applied mineral resource quantitative assessment techniques to forecast and estimate the potential distribution of gas hydrate resources in the northern South China Sea. However, current hydrate samples from the South China Sea are too few to produce models of occurrences. Thus, according to similarity and contrast principles of mineral outputs, we can use a similar hydrate-mining environment with sufficient gas hydrate data as a testing ground for modeling northern South China Sea gas hydrate conditions. We selected the Gulf of Mexico, which has extensively studied gas hydrates, to develop predictive models of gas hydrate distributions, and to test errors in the model. Then, we compared the existing northern South China Sea hydrate-mining data with the Gulf of Mexico characteristics, and collated the relevant data into the model. Subsequently, we applied the model to the northern South China Sea to obtain the potential gas hydrate distribution of the area, and to identify significant exploration targets. Finally, we evaluated the reliability of the predicted results. The south seabed area of Taiwan Bank is recommended as a priority exploration target. The Zhujiang Mouth, Southeast Hainan, and Southwest Taiwan Basins, including the South Bijia Basin, also are recommended as exploration target areas. In addition, the method in this paper can provide a useful predictive approach for gas hydrate resource assessment, which gives a scientific basis for construction and implementation of long-term planning for gas hydrate exploration and general exploitation of the seabed of China.

SWASV speciation of Cd, Pb and Cu for the determination of seawater contamination in the area of the Nicole shipwreck (Ancona coast, Central Adriatic Sea).

Science.gov (United States)

Annibaldi, Anna; Illuminati, Silvia; Truzzi, Cristina; Scarponi, Giuseppe

2011-12-01

The study reports for the first time on the heavy metal contamination of the waters surrounding a shipwreck lying on the sea floor. Square wave anodic stripping voltammetry has been used for a survey of the total and dissolved Cd, Pb and Cu contents of the seawater at the site of the sinking of the Nicole M/V (Coastal Adriatic Sea, Italy). Results show that the hulk has a considerable impact as regards all three metals in the bottom water, especially for the particulate fraction concentrations, which increased by factors of ≈ 9 (Cd), ≈ 3 (Pb) and ≈ 5 (Cu). The contaminated plume extended downstream for about 2 miles. Much lower contamination was observed for dissolved bottom concentrations; nevertheless Pb (0.56 ± 0.03 nmol/L) is higher than the Italian legal limits established for 2015 and Cd (0.23 ± 0.03 nmol/L) is very close the limit of Cd will be exceeded if the hulk is not removed. Copyright © 2011. Published by Elsevier Ltd.

Setting realistic recovery targets for two interacting endangered species, sea otter and northern abalone.

Science.gov (United States)

Chadès, Iadine; Curtis, Janelle M R; Martin, Tara G

2012-12-01

Failure to account for interactions between endangered species may lead to unexpected population dynamics, inefficient management strategies, waste of scarce resources, and, at worst, increased extinction risk. The importance of species interactions is undisputed, yet recovery targets generally do not account for such interactions. This shortcoming is a consequence of species-centered legislation, but also of uncertainty surrounding the dynamics of species interactions and the complexity of modeling such interactions. The northern sea otter (Enhydra lutris kenyoni) and one of its preferred prey, northern abalone (Haliotis kamtschatkana), are endangered species for which recovery strategies have been developed without consideration of their strong predator-prey interactions. Using simulation-based optimization procedures from artificial intelligence, namely reinforcement learning and stochastic dynamic programming, we combined sea otter and northern abalone population models with functional-response models and examined how different management actions affect population dynamics and the likelihood of achieving recovery targets for each species through time. Recovery targets for these interacting species were difficult to achieve simultaneously in the absence of management. Although sea otters were predicted to recover, achieving abalone recovery targets failed even when threats to abalone such as predation and poaching were reduced. A management strategy entailing a 50% reduction in the poaching of northern abalone was a minimum requirement to reach short-term recovery goals for northern abalone when sea otters were present. Removing sea otters had a marginally positive effect on the abalone population but only when we assumed a functional response with strong predation pressure. Our optimization method could be applied more generally to any interacting threatened or invasive species for which there are multiple conservation objectives. © 2012 Society for

Improved Chlorophyll-a Algorithm for the Satellite Ocean Color Data in the Northern Bering Sea and Southern Chukchi Sea

Science.gov (United States)

Lee, Sang Heon; Ryu, Jongseong; Park, Jung-woo; Lee, Dabin; Kwon, Jae-Il; Zhao, Jingping; Son, SeungHyun

2018-03-01

The Bering and Chukchi seas are an important conduit to the Arctic Ocean and are reported to be one of the most productive regions in the world's oceans in terms of high primary productivity that sustains large numbers of fishes, marine mammals, and sea birds as well as benthic animals. Climate-induced changes in primary production and production at higher trophic levels also have been observed in the northern Bering and Chukchi seas. Satellite ocean color observations could enable the monitoring of relatively long term patterns in chlorophyll-a (Chl-a) concentrations that would serve as an indicator of phytoplankton biomass. The performance of existing global and regional Chl-a algorithms for satellite ocean color data was investigated in the northeastern Bering Sea and southern Chukchi Sea using in situ optical measurements from the Healy 2007 cruise. The model-derived Chl-a data using the previous Chl-a algorithms present striking uncertainties regarding Chl-a concentrations-for example, overestimation in lower Chl-a concentrations or systematic overestimation in the northeastern Bering Sea and southern Chukchi Sea. Accordingly, a simple two band ratio (R rs(443)/R rs(555)) algorithm of Chl-a for the satellite ocean color data was devised for the northeastern Bering Sea and southern Chukchi Sea. The MODIS-derived Chl-a data from July 2002 to December 2014 were produced using the new Chl-a algorithm to investigate the seasonal and interannual variations of Chl-a in the northern Bering Sea and the southern Chukchi Sea. The seasonal distribution of Chl-a shows that the highest (spring bloom) Chl-a concentrations are in May and the lowest are in July in the overall area. Chl-a concentrations relatively decreased in June, particularly in the open ocean waters of the Bering Sea. The Chl-a concentrations start to increase again in August and become quite high in September. In October, Chl-a concentrations decreased in the western area of the Study area and the Alaskan

Radioactivity in the northern seas of europe

International Nuclear Information System (INIS)

Carvalho, Fernando P.; Madruga, Maria Jose; Oliveira, Joao M.; Gouveia, Jorge M.; Silva, Lidia

2004-01-01

The recent accidents with nuclear powered Russian submarines, such as the Kursk and the K-159, that took place in the Arctic Seas, give rise to high concerns of the public and the media about the radioactive contamination of marine ecosystems and radiological safety of the European population. Those accidents were preceded by decades of discharges of radioactive liquid effluents into coastal seas of Europe and the dumping of packed radioactive waste into the North Atlantic. Being Portugal one country with high consumption rate of seafood caught in its own coastal waters as well as in far seas including the Ar tic seas, the investigation of the radioactive contamination of fish was investigated. Analysis of fish from the Sea of Labrador, Sea of Iceland and Barents Sea, has shown that gamma-emitting radionuclides of artificial origin are in general not detected. The only gamma emitting radionuclide present is Cs-137, in concentrations not higher than 0.3 Bq/kg. This radionuclide originates in the deposition of radioactive fallout following nuclear weapon tests performed in the fifties and sixties. Radionuclides in fish from northern regions and in fish from the Portuguese coast generally are present in concentrations lower than those currently reported for fish from the Irish Sea and the Baltic Sea, impacted with the discharges of radioactive waste from Sellafield and the deposition of fallout from Chernobyl, respectively. Nevertheless, the potential for future accidents and the radioactive waste dumped into the North Atlantic may in the future modify this scenario and potentially increase the currently very low radionuclide concentration in fish included in the Portuguese diet. Therefore, the research and radiological surveillance must be maintained in order to monitor the radiological risk and to ensure the quality of food available to consumers. (author)

A geographical information system for the management of the aquaculture data in the Adriatic Sea – the Strengthening of Centres for Aquaculture Production and Safety surveillance in the Adriatic countries experience: Present capabilities, tools and functions

Directory of Open Access Journals (Sweden)

Susanna Tora

2017-11-01

Full Text Available The European Commission (EC regulation no. 854/2004 requires a systematic monitoring of chemical and microbiological contaminants in live bivalve molluscs, live echinoderms, live tunicates and live marine gastropods for human consumption through surveillance plans to be implemented in all European Union (EU countries.A consortium of five Adriatic countries was set up in the framework of the Instrument of Pre-accession Assistance Adriatic Cross-border Cooperation Programme (IPA Adriatic CBC 2007- 2013 with the aim of collecting data and distribute information on harvesting and production in mollusc areas. A web-based geographical information system (GIS application was developed to support the partners to manage data and to make these data available to final users, policy makers and to risk assessors. The GIS for the Strengthening of Centres for Aquaculture Production and Safety surveillance in the Adriatic countries (CAPS2 is divided into two levels, the national and the supranational one, and it distributes spatial and epidemiological information coming from various data acquisition and management sites. The great innovation is the possibility for each country to use online drawing, modifying and change of the geographic areas according to national surveillance needs. Currently it hosts data coming from about 230 production and relay areas with more than 29,478 laboratory tests performed on collected samples since August 2014. Data collected are used by each national competent authority to classify production or relay areas according to the EC regulation mentioned and to conduct risk assessment studies to evaluate the level of consumers’ exposure to contaminants in the consumption of bivalve mollusc products.

Simulated wind-generated inertial oscillations compared to current measurements in the northern North Sea

Science.gov (United States)

Bruserud, Kjersti; Haver, Sverre; Myrhaug, Dag

2018-04-01

Measured current speed data show that episodes of wind-generated inertial oscillations dominate the current conditions in parts of the northern North Sea. In order to acquire current data of sufficient duration for robust estimation of joint metocean design conditions, such as wind, waves, and currents, a simple model for episodes of wind-generated inertial oscillations is adapted for the northern North Sea. The model is validated with and compared against measured current data at one location in the northern North Sea and found to reproduce the measured maximum current speed in each episode with considerable accuracy. The comparison is further improved when a small general background current is added to the simulated maximum current speeds. Extreme values of measured and simulated current speed are estimated and found to compare well. To assess the robustness of the model and the sensitivity of current conditions from location to location, the validated model is applied at three other locations in the northern North Sea. In general, the simulated maximum current speeds are smaller than the measured, suggesting that wind-generated inertial oscillations are not as prominent at these locations and that other current conditions may be governing. Further analysis of the simulated current speed and joint distribution of wind, waves, and currents for design of offshore structures will be presented in a separate paper.

Surface drift prediction in the Adriatic Sea using hyper-ensemble statistics on atmospheric, ocean and wave models: Uncertainties and probability distribution areas

Science.gov (United States)

Rixen, M.; Ferreira-Coelho, E.; Signell, R.

2008-01-01

Despite numerous and regular improvements in underlying models, surface drift prediction in the ocean remains a challenging task because of our yet limited understanding of all processes involved. Hence, deterministic approaches to the problem are often limited by empirical assumptions on underlying physics. Multi-model hyper-ensemble forecasts, which exploit the power of an optimal local combination of available information including ocean, atmospheric and wave models, may show superior forecasting skills when compared to individual models because they allow for local correction and/or bias removal. In this work, we explore in greater detail the potential and limitations of the hyper-ensemble method in the Adriatic Sea, using a comprehensive surface drifter database. The performance of the hyper-ensembles and the individual models are discussed by analyzing associated uncertainties and probability distribution maps. Results suggest that the stochastic method may reduce position errors significantly for 12 to 72??h forecasts and hence compete with pure deterministic approaches. ?? 2007 NATO Undersea Research Centre (NURC).

Genetic population structure of European sprat (Sprattus sprattus L.): differentiation across a steep environmental gradient in a small pelagic fish

DEFF Research Database (Denmark)

Limborg, Morten; Pedersen, Jes S.; Hansen, Jakob Hemmer

2009-01-01

locations in and around the North- and Baltic Sea area and from a geographically distant population from the Adriatic Sea. Analyses of nine microsatellite loci revealed a sharp genetic division separating samples from the Northeastern Atlantic and the Baltic Sea (pairwise θ = 0.019–0.035), concurring...... with a steep salinity gradient. We found, at most, weak structure among samples within the Northeastern Atlantic region and within the Baltic Sea (pairwise θ = 0.001–0.009). The Adriatic Sea population was highly differentiated from all northern samples (pairwise θ = 0.071–0.092). Overall, the observed...... population structure resembles that of most other marine fishes studied in the North/Baltic Sea areas. Nevertheless, spatially explicit differences are observed among species, likely reflecting specific life-histories. Such fine-scale population structure should be taken into account, e.g. in ecosystem...

Regulatory Framework on Exploration and Exploitation of Croatian Part of Adriatic

International Nuclear Information System (INIS)

Mudric, M.

2015-01-01

As the prelude to the regulation of marine exploration and exploitation activities in the Croatian Adriatic waters, the new Mining Act and Act on exploration and exploitation of hydrocarbons have provided a general legal framework for the natural resources exploration and exploitation. The latter Act also appropriated the establishment of the independent regulatory body, the Hydrocarbon Agency. It is important to mention the Decree on Fees for exploration and production of hydrocarbons, and the Decree on main technical requirements on safety and security of offshore exploration and production of hydrocarbons in the Republic of Croatia, that are of special relevance for the current activities with regard the proposed project of exploration and exploitation of the Croatian waters in search for gas and oil sea-bed deposits. The Hydrocarbon Agency has published the Strategic Study of the Likely Significant Environmental Impact of the Framework Plan and Program of Exploration and Production of Hydrocarbons in the Adriatic, a document receiving a lot of criticism from the legal experts and general public. At the same time, the experts tend to support the general idea of sea-bed exploration and exploitation, with the major antagonism still being present in the general public, with several initiatives introducing the possibility of a public referenda to oppose the sea-bed exploration and exploitation. The Government is currently preparing the Act on the Safety of Offshore Hydrocarbon Exploration and Production Operations, based on the Directive 94/22/EC of the European Parliament and of the Council of 30 May 1994 on the conditions for granting and using authorizations for the prospection, exploration and production of hydrocarbons, the Commission Implementing Regulation (EU) No 1112/2014 of 13 October 2014 determining a common format for sharing of information on major hazard indicators by the operators and owners of offshore oil and gas installations and a common format

Horsemanship of ancient armies of Northern Black Sea region

Directory of Open Access Journals (Sweden)

K. M. Kolesnykov

2015-06-01

Full Text Available This article deal with the description, analysis and generalization of features of organization and tactics of cavalry of the army ancient states of the Northern Black Sea region: Olbia, Chersonese, Bosporus. Author sure that the foundation of the armed forces of these states was a civil militia – free, economically independent landowners, endowed with the broadest volume of political and social rights men – full citizens. Bosporus kings have attracted a significant number of hired troops that held by the royal treasury income and special direct tax. The cavalry is interacted with heavily armed infantry contingents – hoplites or swordsman­ thyureoforoi. The contingents of lightweight (arrow­toxots and heavy (akontists and spearmen cavalry were presented as part of ancient armies of the Northern Black Sea Region in Classical and Hellenistic periods. In the Roman period on the Bosporus fixed formation units of cathafractarian cavalry. The weapons and tactics of the Sarmatian nomadic nobility (Aspurhianian, Sirak, Aorsy and more were served as a model for Bosporus cataphractarian horsemen.

Levels of 232Th activity in the South Adriatic Sea marine environment of Montenegro

International Nuclear Information System (INIS)

Antovic, N.M.

2010-01-01

232 Th activities in the South Adriatic Sea-water, surface sediment, mud with detritus, seagrass (Posidonia oceanica) samples, and the mullet (Mugilidae) species Mugil cephalus, as well as soil and sand from the Montenegrin Coast, were measured using the six-crystal spectrometer PRIPYAT-2M, which has relatively high detection efficiency and a good sensitivity, and allows a short acquisition time, and measuring samples of any shape, without preliminary preparation and calibration measurements for different sample geometries. An average 232 Th activity concentration in surface soil layer is found to be 40.33 Bq kg -1 , while in sand-4.7 Bq kg -1 . The absorbed dose rate in air due to 232 Th gamma radiation from surface soil layer ranged from 11.76 to 63.39 nGy h -1 , with a mean of 24.06 nGy h -1 . Corresponding average annual effective dose rate has been found to be 0.03 mSv y -1 . The absorbed dose rates due to the thorium gamma radiation in air at 1 m above sand surface on the Montenegrin beaches have been found to be from 0.41 to 9.08 nGy h -1 , while annual effective dose rates ranged from 0.0005 to 0.011 mSv y -1 . 232 Th activity concentration in seawater ranged from 0.06 to 0.22 Bq L -1 , as in the mullet (Mugil cephalus) whole individuals from 0.63 to 1.67 Bq kg -1 . Annual intake of 232 Th by human consumers of this fish species has been estimated to provide an effective dose of about 0.003 mSv y -1 . (author)

Survey of total mercury and methylmercury levels in edible fish from the Adriatic Sea.

Science.gov (United States)

Storelli, M M; Giacominelli-Stuffler, R; Storelli, A; D'Addabbo, R; Palermo, C; Marcotrigiano, G O

2003-12-01

Total mercury and methylmercury concentrations were measured in the muscle tissue of different fish species from the Adriatic Sea to ascertain whether the concentrations exceeded the maximum level fixed by the European Commission. Large species-dependent variability was observed. The highest total mercury mean concentrations were in benthic (0.20-0.76 microg g(-1) wet wt) and demersal fish (0.22-0.73 microg g(-1) wet wt), while pelagic species showed the lowest levels (0.09-0.23 microg g(-1) wet wt). In 15% of frost fish, in 42% of skate and in 30% of angler fish samples total mercury concentrations exceeded the maximum level fixed by the European Commission (Hg = 1 microg g(-1) wet wt); for the species for which the maximum level was set to 0.5 microg g(-1) wet wt, concentrations exceeding the prescribed legal limit were observed in 6.4% of bokkem, in 6.6% of pandora, in 20% of megrin, in 12.5% of four-spotted megrim, in 16% of striped mullet, in 5.0% of forkbeard and in 5.3% of picarel samples. In all the different species, mercury was present almost completely in the methylated form, with mean percentages between 70 and 100%. Weekly intake was estimated and compared with the provisional tolerable weekly intake recommended by the FAO/WHO Expert Committee on Food Additives. A high exposure was associated with the consumption of only skates, frost fish and angler fish, thought the consumption of the other species, such as, megrim, four spotted megrim, red fish striped mullet and forkbeard, resulted in a weekly intake slightly below the established provisional tolerable weekly intake.

Cadmium, lead and organic matter distribution in coastal sediment from the Adriatic Sea

International Nuclear Information System (INIS)

Ujevic, I.; Bogner, D.; Baric, A.

1999-01-01

The spatial distribution of Cd, and Pb has been studied in surface sediments of the eastern Adriatic coastal region. In addition, Pb concentration has been determined in long sediment cores dating back to pre-industrial time. The results indicate that trace metal concentrations in surface sediment layer depend both on pollution sources, and on local characteristics of the marine and terrestrial environment. Generally, most of the concentrations are not high revealing that the coastal area is not heavily polluted. Granulometric and geochemical data indicate the existence of some differences between sediments formed in the vicinity of fresh water input and sediments from areas without fresh water input. (author)

Pacific walrus (Odobenus rosmarus divergens resource selection in the Northern Bering Sea.

Directory of Open Access Journals (Sweden)

Chadwick V Jay

Full Text Available The Pacific walrus is a large benthivore with an annual range extending across the continental shelves of the Bering and Chukchi Seas. We used a discrete choice model to estimate site selection by adult radio-tagged walruses relative to the availability of the caloric biomass of benthic infauna and sea ice concentration in a prominent walrus wintering area in the northern Bering Sea (St. Lawrence Island polynya in 2006, 2008, and 2009. At least 60% of the total caloric biomass of dominant macroinfauna in the study area was composed of members of the bivalve families Nuculidae, Tellinidae, and Nuculanidae. Model estimates indicated walrus site selection was related most strongly to tellinid bivalve caloric biomass distribution and that walruses selected lower ice concentrations from the mostly high ice concentrations that were available to them (quartiles: 76%, 93%, and 99%. Areas with high average predicted walrus site selection generally coincided with areas of high organic carbon input identified in other studies. Projected decreases in sea ice in the St. Lawrence Island polynya and the potential for a concomitant decline of bivalves in the region could result in a northward shift in the wintering grounds of walruses in the northern Bering Sea.

Chemistry of the sea-surface microlayer. 3. Studies on the nutrient chemistry of the northern Arabian Sea

Digital Repository Service at National Institute of Oceanography (India)

Singbal, S.Y.S.; Narvekar, P.V.; Nagarajan, R.

Nutrients showed enrichment in the surface microlayer compared to those in sub-surface water and there was a decreasing trend in the enrichment factor from nearshore to offshore in Northern Arabian Sea. The nutrient concentrations were correlated...

Stability of submarine slopes in the northern South China Sea: a numerical approach

Science.gov (United States)

Zhang, Liang; Luan, Xiwu

2013-01-01

Submarine landslides occur frequently on most continental margins. They are effective mechanisms of sediment transfer but also a geological hazard to seafloor installations. In this paper, submarine slope stability is evaluated using a 2D limit equilibrium method. Considerations of slope, sediment, and triggering force on the factor of safety (FOS) were calculated in drained and undrained ( Φ=0) cases. Results show that submarine slopes are stable when the slope is 13° with earthquake peak ground acceleration (PGA) of 0.5 g; whereas with a weak layer, a PGA of 0.2 g could trigger instability at slopes >10°, and >3° for PGA of 0.5 g. The northern slope of the South China Sea is geomorphologically stable under static conditions. However, because of the possibility of high PGA at the eastern margin of the South China Sea, submarine slides are likely on the Taiwan Bank slope and eastern part of the Dongsha slope. Therefore, submarine slides recognized in seismic profiles on the Taiwan Bank slope would be triggered by an earthquake, the most important factor for triggering submarine slides on the northern slope of the South China Sea. Considering the distribution of PGA, we consider the northern slope of the South China Sea to be stable, excluding the Taiwan Bank slope, which is tectonically active.

Source apportionment of particulate pollutants in the atmosphere over the Northern Yellow Sea

Science.gov (United States)

Wang, L.; Qi, J. H.; Shi, J. H.; Chen, X. J.; Gao, H. W.

2013-05-01

Atmospheric aerosol samples were collected over the Northern Yellow Sea of China during the years of 2006 and 2007, in which the Total Carbon (TC), Cu, Pb, Cd, V, Zn, Fe, Al, Na+, Ca2+, Mg2+, NH4+, NO3-, SO42-, Cl-, and K+ were measured. The principle components analysis (PCA) and positive matrix factorization (PMF) receptor models were used to identify the sources of particulate matter. The results indicated that seven factors contributed to the atmospheric particles over the Northern Yellow Sea, i.e., two secondary aerosols (sulfate and nitrate), soil dust, biomass burning, oil combustion, sea salt, and metal smelting. When the whole database was considered, secondary aerosol formation contributed the most to the atmospheric particle content, followed by soil dust. Secondary aerosols and soil dust consisted of 65.65% of the total mass of particulate matter. The results also suggested that the aerosols over the North Yellow Sea were heavily influenced by ship emission over the local sea area and by continental agricultural activities in the northern China, indicating by high loading of V in oil combustion and high loading of K+ in biomass burning. However, the contribution of each factor varied greatly over the different seasons. In spring and autumn, soil dust and biomass burning were the dominant factors. In summer, heavy oil combustion contributed the most among these factors. In winter, secondary aerosols were major sources. Backward trajectories analysis indicated the 66% of air mass in summer was from the ocean, while the air mass is mainly from the continent in other seasons.

Linking sardine recruitment in coastal areas to ocean currents using surface drifters and HF radar. A case study in the Gulf of Manfredonia, Adriatic Sea

DEFF Research Database (Denmark)

Sciascia, Roberta; Berta, Maristella; Carlson, Daniel Frazier

2017-01-01

Understanding the role of ocean currents in the recruitment of commercially and ecologically important fish is an important step towards developing sustainable resource management guidelines. To this end, we attempt to elucidate the role of surface ocean transport in supplying recruits of sardine...... (Sardinus pilchardus) to the Gulf of Manfredonia, a known recruitment area in the Adriatic Sea. Sardine early life history stages (ELHS) were collected during two cruises to provide observational estimates of age-size relationship and of their passive pelagic larval duration (PPLD). We combine these PPLDs...... in the Gulf is characterized by repeated pulses from remote SAs. This is the first attempt to describe the processes related to Lagrangian connection to, and retention in, the Gulf of Manfredonia that will be complemented in the future using validated numerical ocean models and biophysical models....

Plasma levels of pollutants are much higher in loggerhead turtle populations from the Adriatic Sea than in those from open waters (Eastern Atlantic Ocean).

Science.gov (United States)

Bucchia, Matteo; Camacho, María; Santos, Marcelo R D; Boada, Luis D; Roncada, Paola; Mateo, Rafael; Ortiz-Santaliestra, Manuel E; Rodríguez-Estival, Jaime; Zumbado, Manuel; Orós, Jorge; Henríquez-Hernández, Luis A; García-Álvarez, Natalia; Luzardo, Octavio P

2015-08-01

In this paper we determined the levels of 63 environmental contaminants, including organic (PCBs, organochlorine pesticides, and PAHs) and inorganic (As, Cd, Cu, Pb, Hg and Zn) compounds in the blood of loggerhead turtles (Caretta caretta) from two comparable populations that inhabit distinct geographic areas: the Adriatic Sea (Mediterranean basin) and the Canary Islands (Eastern Atlantic Ocean). All animals were sampled at the end of a period of rehabilitation in centers of wildlife recovery, before being released back into the wild, so they can be considered to be in good health condition. The dual purpose of this paper is to provide reliable data on the current levels of contamination of this species in these geographic areas, and secondly to compare the results of both populations, as it has been reported that marine biota inhabiting the Mediterranean basin is exposed to much higher pollution levels than that which inhabit in other areas of the planet. According to our results it is found that current levels of contamination by organic compounds are considerably higher in Adriatic turtles than in the Atlantic ones (∑PCBs, 28.45 vs. 1.12ng/ml; ∑OCPs, 1.63 vs. 0.19ng/ml; ∑PAHs, 13.39 vs. 4.91ng/ml; pmercury (5.74 vs. 7.59μg/ml, p<0.01). The results of this study confirm that the concentrations are larger in turtles from the Mediterranean, probably related to the high degree of anthropogenic pressure in this basin, and thus they are more likely to suffer adverse effects related to contaminants. Copyright © 2015 Elsevier B.V. All rights reserved.

Description and classification of dictyoceratid sponges from the Northern Red Sea

NARCIS (Netherlands)

Helmy, Tamer; Serehy, el Hamed; Mohamed, Saad Zakaria; Soest, van Rob W.M.

2004-01-01

Seven dictyoceratid sponge species were collected from the Gulf of Aqaba, Northern Red Sea. Two new species were recognized: Scalarispongia aqabaensis n. sp. and Spongia lesleighae n. sp. Five others belong to the known species, Fascaplysinopsis reticulata (Hentschel, 1912), Phyllospongia papyracea

Climatic anomalies in Northern South China Sea during 1986-1987 El Nino

Energy Technology Data Exchange (ETDEWEB)

Chen Tegu (Academia Sinica, Beijing (China)); Zhou Qiang

1990-05-01

In this paper, the climatic anomalies in Northern South China Sea (NSCS) during 1986-1987 El Nino were analyzed according to meteorological and hydrographic observation data. The results showed that the most apparent anomalies were: (1) continuously weaker monsoon strength, (2) continuously much higher South China Sea High Pressure strength; (3) in 1987 only six typhoons occurred in NSCS (four less than normal), with the first typhoon occurring on 25 June, (about one month later than usual); (4) positive air temperature anomaly, negative annual precipitation and evaporation anomaly; (5) sea surface temperature and surface salinity anomaly was positive; (6) monthly mean sea level was 1 to 10cm lower than normal.

Molecular Typing of Vibrio parahaemolyticus Strains Isolated from Mollusks in the North Adriatic Sea.

Science.gov (United States)

Rahman, Mohammad Shamsur; Carraro, Roberta; Cardazzo, Barbara; Carraro, Lisa; Meneguolo, Davide Boscolo; Martino, Maria Elena; Andreani, Nadia Andrea; Bordin, Paola; Mioni, Renzo; Barco, Lisa; Novelli, Enrico; Balzan, Stefania; Fasolato, Luca

2017-08-01

Vibrio parahaemolyticus is an emerging foodborne pathogen in the Mediterranean, usually associated with shellfish consumption. The increase in the number of outbreaks in Europe is primarily associated with the global warming of the ocean that has a great impact on the spread and genetic selection of waterborne pathogens. The primary role of Italy in Europe's mollusk production, together with the fact that cases of infections with V. parahaemolyticus are not always notified to the European community, highlighted the necessity of acquiring new information about the epidemiological involvement of shellfish products. The aim of the study was to provide useful insights into the first steps of the Risk Assessment associated with V. parahaemolyticus through the molecular characterization of isolates from commercialized mollusks. A total of 102 strains identified as V. parahaemolyticus were investigated as part of a larger sampling (1-year survey) from several shellfish species collected from the Venice lagoon and the North Adriatic sea. All strains were characterized by multilocus sequence typing and tested for the presence of virulence genes (trh and tdh). The study of sampling/environmental factors and epidemiological analyses was performed to describe the behaviors of the different genetic populations. The population structure analysis highlighted three genetic clusters that could be subject to temperature selection during cold (≤15°C) and warm (>16°C) seasons. Moreover, other factors, such as molluscan species (clams/mussels), probably played a role in the distribution of genetic clusters. Although few strains carried the virulence factors (n = 6 trh + ), epidemiological links with clinical isolates and a local dissemination of some sequence types were underlined. This work provides a useful background on the genotype spread as a first step in the Hazard Identification in light of future climate changes.

Age, growth and utility of otolith morphometrics as a predictor of age in the wrasse Coris julis (Labridae from the eastern Adriatic Sea

Directory of Open Access Journals (Sweden)

Frane Škeljo

2012-09-01

Full Text Available Age and growth of Coris julis were determined by examining sagittal otoliths belonging to fish sampled between November 2008 and October 2009 in the eastern Adriatic Sea (north-central Mediterranean Sea. A total of 1102 specimens (528 males, 487 females and 87 individuals of indeterminate sex, ranging from 48 to 222 mm total length were analysed. Ninety-two per cent of the otoliths were readable and 68% of the specimens had two readings in agreement. Counting of daily rings revealed that the second opaque ring represents the first annulus (315.1±27.8 daily rings. The maximum observed age was 7 years for males and 5 years for females, with males dominating in higher age classes ( > 3 years and females in age classes 1+ and 2+. Growth was described by the von Bertalanffy growth curves and significant differences were found between males (L∞=29.10 cm, k=0.12 and t0=–1.48 and females (L∞=21.27 cm, k=0.21 and t0=–1.08. Otolith mass, length, width and thickness were determined for the otoliths belonging to 465 fish and the utility of these morphometrics as a predictor of age was evaluated. The most precise age estimations were obtained from the otolith length data, followed by the otolith mass.

Data from investigation on seismic Sea waves events in the Eastern Mediterranean from 1000 to 1500 A.D.

Directory of Open Access Journals (Sweden)

J. ANTONOPOULOS

1980-06-01

Full Text Available Tsunamis from 1000 to 1500 A.D. in the Eastern Mediterranean
Sea between 31-44 N and 18-36 E excluding the Black Sea
and the Italian coasts of the Adriatic Sea is the object of the
present paper.

Data from investigation on seismic Sea waves events in the Eastern Mediterranean from 1900 to 1980 A.D.

Directory of Open Access Journals (Sweden)

J. ANTONOPOULOS

1980-06-01

Full Text Available Tsunamis from 1900 to 1980 A.D. in the Eastern Mediterranean
Sea between 31-44 N and 18-36 E excluding the Black Sea
and the Italian coasts of the Adriatic Sea is the object of the
present paper.

Regional Risk Assessment for the analysis of the risks related to storm surge extreme events in the coastal area of the North Adriatic Sea.

Science.gov (United States)

Rizzi, Jonathan; Torresan, Silvia; Gallina, Valentina; Critto, Andrea; Marcomini, Antonio

2013-04-01

Europe's coast faces a variety of climate change threats from extreme high tides, storm surges and rising sea levels. In particular, it is very likely that mean sea level rise will contribute to upward trends in extreme coastal high water levels, thus posing higher risks to coastal locations currently experiencing coastal erosion and inundation processes. In 2007 the European Commission approved the Flood Directive (2007/60/EC), which has the main purpose to establish a framework for the assessment and management of flood risks for inland and coastal areas, thus reducing the adverse consequences for human health, the environment, cultural heritage and economic activities. Improvements in scientific understanding are thus needed to inform decision-making about the best strategies for mitigating and managing storm surge risks in coastal areas. The CLIMDAT project is aimed at improving the understanding of the risks related to extreme storm surge events in the coastal area of the North Adriatic Sea (Italy), considering potential climate change scenarios. The project implements a Regional Risk Assessment (RRA) methodology developed in the FP7 KULTURisk project for the assessment of physical/environmental impacts posed by flood hazards and employs the DEcision support SYstem for Coastal climate change impact assessment (DESYCO) for the application of the methodology to the case study area. The proposed RRA methodology is aimed at the identification and prioritization of targets and areas at risk from water-related natural hazards in the considered region at the meso-scale. To this aim, it integrates information about extreme storm surges with bio-geophysical and socio-economic information (e.g. vegetation cover, slope, soil type, population density) of the analyzed receptors (i.e. people, economic activities, cultural heritages, natural and semi-natural systems). Extreme storm surge hazard scenarios are defined using tide gauge time series coming from 28 tide gauge

Study of hydrocarbons in bottom sediments of the northern Dvina River-White Sea geochemical barrier during spring flood. Volume 2

International Nuclear Information System (INIS)

Nemirovskaya, I.; Shevchenko, V.

2007-01-01

The Northern Dvina in Northern Russia is the main river of the White Sea reservoir. The water discharge is 108 km 3 per year. With active shipping and several large pulp and paper mills that operate in the region, the river is a supplier of polluting substances. Weathered oil and pyrogenic compounds dominate the composition of hydrocarbons. During flooding, the Northern Dvina - Dvina Bay geochemical barrier becomes a filter, which prevents pollutants from penetrating to the White Sea. This paper summarized data on the concentration and composition of hydrocarbons, aliphatic hydrocarbons (AHC) and polycyclic aromatic hydrocarbons (PAH) in the marine water and bottom sediments at the mouth of the Northern Dvina/White Sea. Nearly similar concentrations of organic compounds were found in the Northern Dvina River water and in the near-mouth White Sea water area. However, their distribution conforms to the marginal filter rules. Natural terrigenous hydrocarbon compounds were found to dominate in all forms. Biogenic autochthonous hydrocarbons were detected in the near-shore areas and in the outer zone of the marginal filter of the Northern Dvina River, where PAH are formed together with AHC. 20 refs., 2 tabs., 4 figs

Post-rift magmatism in the Pearl River Mouth Basin, northern South China Sea

Science.gov (United States)

Xu, H.; Zhao, F.; Xia, S.; Sun, J.; Fan, C.

2017-12-01

Multi-beam, 2D seismic reflection and borehole data reveal that post-rift magmatism are widespread in the northern margin of South China Sea. A large-scale volcanic complex was identified at water depths of 500 to 3000 m, covering an area of ca. 8000 km2. This volcanic complex includes seamounts, igneous sills, dykes and intruded volcanic bodies. Combining data from exploration wells BY7-1 and BY2 with published seismic stratigraphic data, we can highlight multiple extrusive events from the Early Oligocene to Early Miocene, reflecting progressive continental breakup in the South China Sea. Most intruded magma through the continental crust also uplifted sediments up to the T6 unconformity. Given the evidence in this work that Early Miocene magmatic bodies were developed above or along faults, we suggest that post-rift magmatism in the northern margin of the South China Sea was largely controlled by the faults. Reactivation events in the faults are suggested to have generated preferential vertical pathways for the ascent of magma within a context of progressive continental breakup and thinned continental crust, as the South China Sea was being formed.

The major tectonic boundaries of the Northern Red Sea rift, Egypt derived from geophysical data analysis

Science.gov (United States)

Saleh, Salah; Pamukçu, Oya; Brimich, Ladislav

2017-09-01

In the present study, we have attempted to map the plate boundary between Arabia and Africa at the Northern Red Sea rift region including the Suez rift, Gulf of Aqaba-Dead Sea transform and southeastern Mediterranean region by using gravity data analysis. In the boundary analysis method which was used; low-pass filtered gravity anomalies of the Northern Red Sea rift region were computed. Different crustal types and thicknesses, sediment thicknesses and different heat flow anomalies were evaluated. According to the results, there are six subzones (crustal blocks) separated from each other by tectonic plate boundaries and/or lineaments. It seems that these tectonic boundaries reveal complex structural lineaments, which are mostly influenced by a predominant set of NNW-SSE to NW-SE trending lineaments bordering the Red Sea and Suez rift regions. On the other side, the E-W and N-S to NNE-SSW trended lineaments bordering the South-eastern Mediterranean, Northern Sinai and Aqaba-Dead Sea transform regions, respectively. The analysis of the low pass filtered Bouguer anomaly maps reveals that the positive regional anomaly over both the Red Sea rift and South-eastern Mediterranean basin subzones are considered to be caused by the high density of the oceanic crust and/or the anomalous upper mantle structures beneath these regions whereas, the broad medium anomalies along the western half of Central Sinai with the Suez rift and the Eastern Desert subzones are attributed to low-density sediments of the Suez rift and/or the thick upper continental crustal thickness below these zones. There are observable negative anomalies over the Northern Arabia subzone, particularly in the areas covered by Cenozoic volcanics. These negative anomalies may be attributed to both the low densities of the surface volcanics and/or to a very thick upper continental crust. On the contrary, the negative anomaly which belongs to the Gulf of Aqaba-Dead Sea transform zone is due to crustal thickening

Radiocaesium in the seas of northern Europe: 1980-84

International Nuclear Information System (INIS)

Camplin, W.C.; Steele, A.K.

1991-01-01

A computer data base of measurements of caesium-134 and caesium-137 in sea water has been compiled. The measurements were carried out by the UK Ministry of Agriculture, Fisheries and Food and include data for the Irish Sea, Bristol Channel, English Channel, North Sea, Scottish waters and other parts of the marine environment of northern Europe. This report covers the sampling period 1980-84 and further information will be published as the data base is expanded. It is hoped that the information will be useful to scientists modelling radionuclide dispersion in the area. In order to assist in the development of new models, diskettes of the data in ASCII files are available, on request, from the first author. The data include the locations of sample collection, collection date, depth salinity, concentration of activity and counting errors. Plots of the geographical scope of the data are also provided to assist the user. (author)

Structural and functional responses of harpacticoid copepods to anoxia in the Northern Adriatic: an experimental approach

Directory of Open Access Journals (Sweden)

M. De Troch

2013-06-01

Full Text Available Combined in situ and laboratory studies were conducted to document the effects of anoxia on the structure and functioning of meiobenthic communities, with special focus on harpacticoid copepods. In a first step, anoxia was created artificially by means of an underwater chamber at 24 m depth in the Northern Adriatic, Gulf of Trieste (Mediterranean. Nematodes were found as the most abundant taxon, followed by harpacticoid copepods. While nematode densities were not affected by treatment (anoxia/normoxia or sediment depth, these factors had a significant impact on copepod abundances. Harpacticoid copepod family diversity, in contrast, was not affected by anoxic conditions, only by depth. Ectinosomatidae and Cletodidae were most abundant in both normoxic and anoxic samples. The functional response of harpacticoid copepods to anoxia was studied in a laboratory tracer experiment by adding 13C pre-labelled diatoms to sediment cores in order to test (1 if there is a difference in food uptake by copepods under normoxic and anoxic conditions and (2 whether initial (normoxia feeding of harpacticoid copepods on diatoms results in a better survival of copepods in subsequent anoxic conditions. Independent of the addition of diatoms, there was a higher survival rate in normoxia than anoxia. The supply of additional food did not result in a higher survival rate of copepods in anoxia, which might be explained by the presence of a nutritionally better food source and/or a lack of starvation before adding the diatoms. However, there was a reduced grazing pressure by copepods on diatoms in anoxic conditions. This resulted in a modified fatty acid composition of the sediment. We concluded that anoxia not only impacts the survival of consumers (direct effect but also of primary producers (indirect effect, with important implications for the recovery phase.

Front affecting the distribution of seabirds in the northern Bering Sea

OpenAIRE

Harrison, Nancy M.; L Hunt Jr., George; Cooney, Robert T.

1990-01-01

We observed seabirds aggregated at a front marking the boundary between two water masses in the Bering Sea. Least Auklets (Aethia pusilla) were most abundant at the front; surface-feeding species including Northern Fulmars (Fulmarus glacialis), Black-legged Kittiwakes (Rissa tridactyla) and Red Phalaropes (Phalaropusfuscus) were also present.

THE NORTHERN SEA ROUTE: PRESENT CONDITION AND DEVELIPMENT PROSPECTS

Directory of Open Access Journals (Sweden)

R. A. Bryzgalov

2011-01-01

Full Text Available The Northern Sea Route (NSR represents a serious alternative to traditional so-called «southern» sea transportation routes passing through the Suez Canal. Data on the present and on most optimistic prospective scopes of transportation over NSR for different types of goods are presented in the article. Among main factors working for the optimistic perspective with respect of NSR there are measurements stipulated in several Russian governmental decrees, global rise in temperature and feasibility to develop natural resources abundantly available in the arctic areas of Russia. Still, there are negative factors such as the need of massive investment to transportation means and to local infrastructure, risks associated with the probability of particularly severe arctic natural phenomena and provision for safety in many aspects.

Late Holocene hydrographic settings of the northern Red Sea

Directory of Open Access Journals (Sweden)

Amani Badawi

2016-03-01

Full Text Available Temporal variability of the paleo-oceanographic setting of the northern Red Sea during the last 6 Ky was deduced from high-resolution faunal results and stable isotope records of planktonic foraminifera in three short cores sediment obtained by the German R/V Meteor vessel. In general, the investigated time interval is fundamentally comparable to the present day composition and distribution of planktonic foraminifera. However, interrupted short enhanced arid phase spanning the last 4–2 Ky appears to have existed in the northern Red Sea, and resulted in elevation of salinity and somehow productivity, as hypersaline, dense surface water favored vertical mixing of the water column resulting in an increase in productivity. This paleoclimatic reconstruction is revealed from the distinct gradient in the composition and distribution of planktonic foraminifera, as well as the significant distribution trend of Globigerinoides ruber versus Globigerinoides sacculifer correlated with the stable isotope records. Starting from the last 2 Ky to the present time, less strength arid conditions relative to the previous period prevailed, reflected from a gradual decrease in surface water salinity and productivity assuming that the present water conditions and consequently current climatic conditions began to develop from that time with minor fluctuations reaching the recent conditions.

Modeling the biogeochemical impact of atmospheric phosphate deposition from desert dust and combustion sources to the Mediterranean Sea

Science.gov (United States)

Richon, Camille; Dutay, Jean-Claude; Dulac, François; Wang, Rong; Balkanski, Yves

2018-04-01

Daily modeled fields of phosphate deposition to the Mediterranean from natural dust, anthropogenic combustion and wildfires were used to assess the effect of this external nutrient on marine biogeochemistry. The ocean model used is a high-resolution (1/12°) regional coupled dynamical-biogeochemical model of the Mediterranean Sea (NEMO-MED12/PISCES). The input fields of phosphorus are for 2005, which are the only available daily resolved deposition fields from the global atmospheric chemical transport model LMDz-INCA. Traditionally, dust has been suggested to be the main atmospheric source of phosphorus, but the LMDz-INCA model suggests that combustion is dominant over natural dust as an atmospheric source of phosphate (PO4, the bioavailable form of phosphorus in seawater) for the Mediterranean Sea. According to the atmospheric transport model, phosphate deposition from combustion (Pcomb) brings on average 40.5×10-6 mol PO4 m-2 yr-1 over the entire Mediterranean Sea for the year 2005 and is the primary source over the northern part (e.g., 101×10-6 mol PO4 m-2 yr-1 from combustion deposited in 2005 over the north Adriatic against 12.4×10-6 from dust). Lithogenic dust brings 17.2×10-6 mol PO4 m-2 yr-1 on average over the Mediterranean Sea in 2005 and is the primary source of atmospheric phosphate to the southern Mediterranean Basin in our simulations (e.g., 31.8×10-6 mol PO4 m-2 yr-1 from dust deposited in 2005 on average over the south Ionian basin against 12.4×10-6 from combustion). The evaluation of monthly averaged deposition flux variability of Pdust and Pcomb for the 1997-2012 period indicates that these conclusions may hold true for different years. We examine separately the two atmospheric phosphate sources and their respective flux variability and evaluate their impacts on marine surface biogeochemistry (phosphate concentration, chlorophyll a, primary production). The impacts of the different phosphate deposition sources on the biogeochemistry of the

The lithosphere-asthenosphere system in the Calabrian Arc and surrounding seas

Energy Technology Data Exchange (ETDEWEB)

Panza, G F [Department of Earth Sciences, University of Trieste, Trieste (Italy); [Abdus Salam International Centre for Theoretical Physics, SAND Group, Trieste (Italy)]. E-mail: panza@dst.univ.trieste.it; Pontevivo, A [Department of Earth Sciences, University of Trieste, Trieste (Italy)

2002-10-01

Through the non-linear inversion of Surface-Wave Tomography data, using as a priori constraints seismic data from literature, it has been possible to define a fairly detailed structural model of the lithosphere-asthenosphere system (thickness, S-wave and P-wave velocities of the crust and of the upper mantle layers) in the Calabrian Arc region (Southern Tyrrhenian Sea, Calabria and the Northern-Western part of the Ionian Sea). The main features identified by our study are: (1) a very shallow (less then 10 km deep) crust-mantle transition in the Southern Tyrrhenian Sea and very low S-wave velocities just below a very thin lid in correspondence of the submarine volcanic bodies in the study area; (2) a shallow and very low S-wave velocity layer in the mantle in the areas of Aeolian islands, of Vesuvius, Ischia and Phlegraean Fields, representing their shallow-mantle magma source; (3) a thickened continental crust and lithospheric doubling in Calabria; (4) a crust about 25 km thick and a mantle velocity profile versus depth consistent with the presence of a continental rifled, now thermally relaxed, lithosphere in the investigated part of the Ionian Sea; (5) the subduction of the Ionian lithosphere towards NW below the Tyrrhenian Basin; (6) the subduction of the Adriatic lithosphere underneath the Vesuvius and Phlegraean Fields. (author)

Sea otters in the northern Pacific Ocean

Science.gov (United States)

Bodkin, James L.; Jameson, Ronald J.; Estes, James A.; LaRoe, Edward T.; Farris, Gaye S.; Puckett, Catherine E.; Doran, Peter D.; Mac, Michael J.

1995-01-01

About 250 years ago sea otters (Enhydra lutris) were distributed continuously from central Baja California, north and west along the Pacific Rim to Machatka Peninsula in Russia, and south along the Kuril Island to northern Japan (Kenyon 1969; Fig. 1a). Several hundred thousand sea otters may have occurred in the north Pacific region when commercial hunting began in the 18th century (Riedman and Estes 1990).At least two attributes of the sea otter have influenced humans, likely for as long as they have resided together along the coast of the north Pacific Ocean. First, sea otters rely on a dense fur, among the finest in the world, for insulation in the cold waters of the Pacific Ocean. The demand for sea otter fur led to their near extinction in the 19th century. The fur harvest, begun about 1740 and halted by international treaty in 1911, left surviving colonies, each likely numbering less than a few hundred animals, in California, south-central Alaska, and the Aleutian, Medney, and Kuril Islands (Fig. 1a). These individuals provided the nucleus for the recovery of the species. Today more than 100,000 sea otters occur throughout about 75% of their original range (fig. 1b). Immigration has resulted in near-complete occupation of the Aleutian and Kuril archipelagos and the Alaska peninsula. Successful translocations have resulted in viable populations in southeast Alaska, Washington, and British Columbia. Large amounts of unoccupied habitat remain along the coasts of Russia, Canada, the United States, and Mexico.The second potential source of conflict between sea otters and humans is that sea otters prey on and often limit some benthic invertebrate populations. Because some of these invertebrates are aso used by humans (Estes and VanBlaricom 1985), human perceptions about the effects of sea otter foraging on invertebrates sometimes differ. By limiting populations of herbivorous invertebrates (e.g., sea urchins [Echinoidea]) otters help maintain the integrity of kelp

Mitochondrial DNA reveals genetic structuring of Pinna nobilis across the Mediterranean Sea.

Directory of Open Access Journals (Sweden)

Daria Sanna

Full Text Available Pinna nobilis is the largest endemic Mediterranean marine bivalve. During past centuries, various human activities have promoted the regression of its populations. As a consequence of stringent standards of protection, demographic expansions are currently reported in many sites. The aim of this study was to provide the first large broad-scale insight into the genetic variability of P. nobilis in the area that encompasses the western Mediterranean, Ionian Sea, and Adriatic Sea marine ecoregions. To accomplish this objective twenty-five populations from this area were surveyed using two mitochondrial DNA markers (COI and 16S. Our dataset was then merged with those obtained in other studies for the Aegean and Tunisian populations (eastern Mediterranean, and statistical analyses (Bayesian model-based clustering, median-joining network, AMOVA, mismatch distribution, Tajima's and Fu's neutrality tests and Bayesian skyline plots were performed. The results revealed genetic divergence among three distinguishable areas: (1 western Mediterranean and Ionian Sea; (2 Adriatic Sea; and (3 Aegean Sea and Tunisian coastal areas. From a conservational point of view, populations from the three genetically divergent groups found may be considered as different management units.

Marine conservation and accession: the future for the Croatian Adriatic.

Science.gov (United States)

Mackelworth, Peter; Holcer, Draško; Jovanović, Jelena; Fortuna, Caterina

2011-04-01

The European Union (EU) is the world's largest trading bloc and the most influential supra-national organisation in the region. The EU has been the goal for many eastern European States, for Croatia accession remains a priority and underpins many of its national policies. However, entry into the EU requires certain commitments and concessions. In October 2003 the Croatian parliament declared an ecological and fisheries protection zone in the Adriatic. Under pressure the zone was suspended, finally entering into force in March 2008 exempting EU States. There are other marine conflicts between Croatia and the EU, particularly the contested maritime border with Slovenia, and the development of the Croatian fishing fleet in opposition to the Common Fisheries Policy. Conversely, attempts to harmonise Croatian Nature Protection with the EU Habitats Directive, facilitated by pre-accession funding, has galvanised conservation policy. Since 2005 two marine protected areas have been declared, significantly increasing the marine ecosystem under protection. Finally, the development of the Marine Strategy Framework Directive is the latest EU attempt to integrate environmental policy in the maritime realm. This will have an effect not only on member States but neighbouring countries. For marine nature protection to be effective in the region the Adriatic Sea needs to be viewed as a mutually important shared and limited resource not a bargaining chip. Negotiations of the EU and Croatia have been watched closely by the other Balkan States and precedents set in this case have the potential to affect EU expansion to the East.

Can Asian Dust Trigger Phytoplankton Blooms in the Oligotrophic Northern South China Sea?

Science.gov (United States)

Wang, Sheng Hsiang; Hsu, Nai-Yung Christina; Tsay, Si-Chee; Lin, Neng-Huei; Sayer, Andrew M.; Huang, Shih-Jen; Lau, William K. M.

2012-01-01

Satellite data estimate a high dust deposition flux (approximately 18 g m(exp-2 a(exp-1) into the northern South China Sea (SCS). However, observational evidence concerning any biological response to dust fertilization is sparse. In this study, we combined long-term aerosol and chlorophyll-a (Chl-a) measurements from satellite sensors (MODIS and SeaWiFS) with a 16-year record of dust events from surface PM10 observations to investigate dust transport, flux, and the changes in Chl-a concentration over the northern SCS. Our result revealed that readily identifiable strong dust events over this region, although relatively rare (6 cases since 1994) and accounting for only a small proportion of the total dust deposition (approximately 0.28 g m(exp-2 a(exp-1), do occur and could significantly enhance phytoplankton blooms. Following such events, the Chl-a concentration increased up to 4-fold, and generally doubled the springtime background value (0.15 mg m(exp-3). We suggest these heavy dust events contain readily bioavailable iron and enhance the phytoplankton growth in the oligotrophic northern SCS.

Zooplankton standing stock, community structure and diversity in the northern Arabian Sea

Digital Repository Service at National Institute of Oceanography (India)

Goswami, S.C.; Srivastava, Y.

The effects of large scale oil spill, which occurred during the Gulf War in 1991 on zooplankton standing stock, community structure and diversity in the northern Arabian Sea were studied. Surface (1-0 m) and vertical zooplankton hauls (200-0 m, 250...

The East Asian shore crab Hemigrapsus sanguineus (Brachyura: Varunidae in the Mediterranean Sea: an independent human-mediated introduction

Directory of Open Access Journals (Sweden)

Christoph D. Schubart

2003-06-01

Full Text Available A single adult male specimen of the East Asian crab Hemigrapsus sanguineus (de Haan, 1835 was collected in August 2001 in the northern Adriatic Sea along the northwest coast of the peninsula of Istra. This is the first record of this genus and species from the Mediterranean Sea. Previously, Hemigrapsus sanguineus had been reported to invade the Atlantic coasts of North America and of western France, while the congeneric East Asian species, Hemigrapsus penicillatus (de Haan, 1835, has established breeding populations along the Atlantic coast of Europe. The current absence of Hemigrapsus sanguineus in southern Europe and the western Mediterranean suggests an independent human-mediated introduction of the Croatian specimen. Preliminary genetic analyses reveal that specimens from Istra, North America, and Japan have identical DNA haplotypes corresponding to the mitochondrial large subunit rRNA gene (16S mtDNA, while the homologous sequence from a specimen of Taiwan differs in two out of 525 nucleotides.

Land-sea coupling of early Pleistocene glacial cycles in the southern North Sea exhibit dominant Northern Hemisphere forcing

Science.gov (United States)

Donders, Timme H.; van Helmond, Niels A. G. M.; Verreussel, Roel; Munsterman, Dirk; ten Veen, Johan; Speijer, Robert P.; Weijers, Johan W. H.; Sangiorgi, Francesca; Peterse, Francien; Reichart, Gert-Jan; Sinninghe Damsté, Jaap S.; Lourens, Lucas; Kuhlmann, Gesa; Brinkhuis, Henk

2018-03-01

We assess the disputed phase relations between forcing and climatic response in the early Pleistocene with a spliced Gelasian (˜ 2.6-1.8 Ma) multi-proxy record from the southern North Sea basin. The cored sections couple climate evolution on both land and sea during the intensification of Northern Hemisphere glaciation (NHG) in NW Europe, providing the first well-constrained stratigraphic sequence of the classic terrestrial Praetiglian stage. Terrestrial signals were derived from the Eridanos paleoriver, a major fluvial system that contributed a large amount of freshwater to the northeast Atlantic. Due to its latitudinal position, the Eridanos catchment was likely affected by early Pleistocene NHG, leading to intermittent shutdown and reactivation of river flow and sediment transport. Here we apply organic geochemistry, palynology, carbonate isotope geochemistry, and seismostratigraphy to document both vegetation changes in the Eridanos catchment and regional surface water conditions and relate them to early Pleistocene glacial-interglacial cycles and relative sea level changes. Paleomagnetic and palynological data provide a solid integrated timeframe that ties the obliquity cycles, expressed in the borehole geophysical logs, to Marine Isotope Stages (MIS) 103 to 92, independently confirmed by a local benthic oxygen isotope record. Marine and terrestrial palynological and organic geochemical records provide high-resolution reconstructions of relative terrestrial and sea surface temperature (TT and SST), vegetation, relative sea level, and coastal influence.During the prominent cold stages MIS 98 and 96, as well as 94, the record indicates increased non-arboreal vegetation, low SST and TT, and low relative sea level. During the warm stages MIS 99, 97, and 95 we infer increased stratification of the water column together with a higher percentage of arboreal vegetation, high SST, and relative sea level maxima. The early Pleistocene distinct warm-cold alterations are

Biochemical biomarker responses to pollution in selected sentinel organisms across the Eastern Mediterranean and the Black Sea

KAUST Repository

Tsangaris, Catherine; Moschino, Vanessa; Strogyloudi, Evangelia; Coatu, Valentina; Ramšak, Andreja; Abu Alhaija, Rana; Carvalho, Susana; Felline, Serena; Kosyan, Alisa; Lazarou, Yiota; Hatzianestis, Ioannis; Oros, Andra; Tiganus, Daniela

2015-01-01

Pollution effects were assessed by means of biochemical biomarkers (catalase, glutathione S-transferase and acetylcholinesterase activities, and metallothioneins content) in five species at selected coastal sites across the Eastern Mediterranean and the Black Sea. The mussel Mytilus galloprovincialis, a well-established sentinel species, was investigated in the Adriatic Sea, Aegean Sea, and Black Sea. The mussel Brachidontes pharaonis and the striped red mullet Mullus surmuletus were used in the Levantine Sea where M. galloprovincialis is not present. The white seabream Diplodus sargus sargus and the gastropod Rapana venosa were additionally sampled in the Adriatic and the Black Sea, respectively. Mussels showed catalase, glutathione S-transferase, and acetylcholinesterase responses to pollution in most geographical areas while the response of metallothioneins was restricted to a few sites. R. venosa showed marked responses of catalase and metallothioneins whereas both fish species did not generally exhibit variations in biomarker values among sites. The approach based on the reference deviation concept using the “Integrated Biological Responses version 2” index was useful for the interpretation of overall biomarker responses.

Biochemical biomarker responses to pollution in selected sentinel organisms across the Eastern Mediterranean and the Black Sea

KAUST Repository

Tsangaris, Catherine

2015-09-23

Pollution effects were assessed by means of biochemical biomarkers (catalase, glutathione S-transferase and acetylcholinesterase activities, and metallothioneins content) in five species at selected coastal sites across the Eastern Mediterranean and the Black Sea. The mussel Mytilus galloprovincialis, a well-established sentinel species, was investigated in the Adriatic Sea, Aegean Sea, and Black Sea. The mussel Brachidontes pharaonis and the striped red mullet Mullus surmuletus were used in the Levantine Sea where M. galloprovincialis is not present. The white seabream Diplodus sargus sargus and the gastropod Rapana venosa were additionally sampled in the Adriatic and the Black Sea, respectively. Mussels showed catalase, glutathione S-transferase, and acetylcholinesterase responses to pollution in most geographical areas while the response of metallothioneins was restricted to a few sites. R. venosa showed marked responses of catalase and metallothioneins whereas both fish species did not generally exhibit variations in biomarker values among sites. The approach based on the reference deviation concept using the “Integrated Biological Responses version 2” index was useful for the interpretation of overall biomarker responses.

Biochemical biomarker responses to pollution in selected sentinel organisms across the Eastern Mediterranean and the Black Sea.

Science.gov (United States)

Tsangaris, Catherine; Moschino, Vanessa; Strogyloudi, Evangelia; Coatu, Valentina; Ramšak, Andreja; Alhaija, Rana Abu; Carvalho, Susana; Felline, Serena; Kosyan, Alisa; Lazarou, Yiota; Hatzianestis, Ioannis; Oros, Andra; Tiganus, Daniela

2016-01-01

Pollution effects were assessed by means of biochemical biomarkers (catalase, glutathione S-transferase and acetylcholinesterase activities, and metallothioneins content) in five species at selected coastal sites across the Eastern Mediterranean and the Black Sea. The mussel Mytilus galloprovincialis, a well-established sentinel species, was investigated in the Adriatic Sea, Aegean Sea, and Black Sea. The mussel Brachidontes pharaonis and the striped red mullet Mullus surmuletus were used in the Levantine Sea where M. galloprovincialis is not present. The white seabream Diplodus sargus sargus and the gastropod Rapana venosa were additionally sampled in the Adriatic and the Black Sea, respectively. Mussels showed catalase, glutathione S-transferase, and acetylcholinesterase responses to pollution in most geographical areas while the response of metallothioneins was restricted to a few sites. R. venosa showed marked responses of catalase and metallothioneins whereas both fish species did not generally exhibit variations in biomarker values among sites. The approach based on the reference deviation concept using the "Integrated Biological Responses version 2" index was useful for the interpretation of overall biomarker responses.

Microbial pollution indicators and culturable heterotrophic bacteria in a Mediterranean area (Southern Adriatic Sea Italian coasts)

Science.gov (United States)

Stabili, L.; Cavallo, R. A.

2011-05-01

In the present study we evaluated the degree of microbial water pollution along the coast line between Brindisi and Santa Maria di Leuca (Southern Adriatic Sea) as well as the culturable heterotrophic bacteria abundances and biodiversity in relation to the microbiological quality of the water. A total of 3773 colonies were isolated, subcultured and identified by several morphological, cultural and biochemical methods including the standardized API 20 E and API 20 NE tests. Along the examined coastal tract the microbial pollution indicators were always below the tolerance limits for bathing waters defined by the CEE directive, suggesting a good sanitary quality. Concerning culturable heterotrophic bacteria, different temporal density trends were observed in the four sites in relation to their geographical position. A positive relationship between the bacterial abundances and the temperature was observed in S. Cataldo and Otranto. The culturable bacterial community was mainly composed of the genera Aeromonas, Pseudomonas, Photobacterium and Flavobacterium. The Enterobacteriaceae family represented a conspicuous component of the bacterial community too. Bacilli were predominant among the Gram-positive bacteria. Of interest is the isolation of yeasts (2% at the surface and 1% at the bottom) taking into account their capability of biodegradation of various materials. Because of the low level of microbial pollution recorded, our results are indicative of the natural variation and diversity of the culturable bacterial community in such an oligotrophic ecosystem and could represent a good point of comparison with other ecosystems as well as a baseline for long term studies aimed to evaluate the effects of environmental fluctuations and human impacts on this aspect of biodiversity in coastal areas.

Climate warming and interannual variability of phytoplankton phenology in the Northern Red Sea

KAUST Repository

Gittings, John

2016-01-01

of phytoplankton biomass), we investigate the potential impacts of climate warming on phytoplankton abundance and phenology in the Northern Red Sea by exploring the mechanistic links with the regional physical environment. The results of the analysis reveal that

Water circulation and recharge pathways of coastal lakes along the southern Baltic Sea in northern Poland

Directory of Open Access Journals (Sweden)

Cieśliński Roman

2016-12-01

Full Text Available The purpose of this paper is to describe water circulation patterns for selected lakes found along the Baltic coast in northern Poland and to determine primary recharge mechanisms or pathways that produce an influx or loss of lake water. A secondary purpose of the paper is to determine the magnitude of recharge for each studied source of water – river water influx, surface runoff from direct catchments, forced influx from polders surrounding lakes, and periodic marine water intrusions from the nearby Baltic Sea. It is also important to determine the magnitude of water outflow from lakes to the sea via existing linkages as well as to compare horizontal influx and outflow data. The study area consisted of five lakes located along the Baltic Sea in northern Poland: Łebsko, Gardno, Bukowo, Kopań, Resko Przymorskie. The main driving force of the studied lakes are large rivers that drain lake catchment areas and periodic brackish water intrusions by the Baltic Sea.

Evaluation and identification of histamine-forming bacteria on fish products of middle Adriatic Sea

Directory of Open Access Journals (Sweden)

Rocco Mancusi

2013-04-01

Full Text Available Regulation EU 2073/2005 sets maximum concentration for histamine in fish and products thereof. To meet these criteria, manufacturers have to define performance objectives, such as the maximum allowed prevalence and number/activity of histamine-producing bacteria at relevant stage of production. In order to assess the presence and decarboxylase activity of contaminant bacteria we examined 51 samples of blue fish caught and processed in Emilia Romagna region. We collected 50 gr of fish (skin and gills or the entire product from 10 sample units from every lot. Analytical samples were cultured in Trypticase Soy Broth supplemented with histidine and pyridoxal HCl. Histamine was measured with an electrochemical biosensor after incubation at both 37°C for 24 h and 18-22°C for 48 h. Enrichments that showed relevant enzymatic activity were seeded on Niven agar to isolate suspected colonies and DNA extracts from these bacteria were analyzed by polymerase chain reaction (PCR for detecting specific sequences of the gene encoding pyridoxaldependent histidine decarboxylase (HDC. Overall, 29.4% samples showed relevant production of histamine in broth cultures (above a cut-off value set at 250 ng/mL and 53.3% of them (8 out of 15 samples allowed detection of HDC positive strains. All of them were typed as Morganella, which appears to be the most common of fish caught in middle Adriatic sea. Ten out of the twelve positive samples with enrichment cultures incubated at both 37 and 18-22°C (83% showed higher decarboxylase activity at room temperature, suggesting the presence of psychrotolerant strains. In addition, the prevalence of histamine-producing bacteria was higher at retail than at production level, probably as a consequence of manipulations and cross-contamination. The risk correlated to development of histamine-producing psychrotolerans bacteria cannot be controlled only with storage temperature: it is necessary for the food business operators to

Enhanced dissolved lipid production as a response to the sea surface warming

Science.gov (United States)

Novak, Tihana; Godrijan, Jelena; Pfannkuchen, Daniela Marić; Djakovac, Tamara; Mlakar, Marina; Baricevic, Ana; Tanković, Mirta Smodlaka; Gašparović, Blaženka

2018-04-01

The temperature increase in oceans reflects on marine ecosystem functioning and surely has consequences on the marine carbon cycle and carbon sequestration. In this study, we examined dissolved lipid, lipid classes and dissolved organic carbon (DOC) production in the northern Adriatic Sea, isolated diatom Chaetoceros pseudocurvisetus batch cultures grown in a wide temperature range (10-30 °C) and in contrasting nutrient regimes, phosphorus (P)-depleted and P-replete conditions. Additionally, lipids and DOC were analyzed in the northern Adriatic (NA) in two stations characterized with different P availability, occupied from February to August 2010 that covered a temperature range from 9.3 to 31.1 °C. To gain insight into factors governing lipid and lipid classes' production in the NA, apart from temperature (T), Chlorophyll a, phytoplankton community abundance and structure, nutrient concentrations were measured together with hydrographic parameters. We found enhanced accumulation of dissolved lipids, particulary glycolipids, with increasing T, especially during the highest in situ temperature. The effect of T on enhanced dissolved lipid release is much more pronounced under P-deplete conditions indicating that oligotrophic regions might be more vulnerable to T rise. Temperature between 25 and 30 °C is a threshold T range for C. pseudocurvisetus, at which a significant part of lipid production is directed toward the dissolved phase. Unlike monocultures, there are multiple factors influencing produced lipid composition, distribution and cycling in the NA that may counteract the T influence. The possible role of enhanced dissolved lipid concentration for carbon sequestration at elevated T is discussed. On the one hand, lipids are buoyant and do not sink, which enhances their retention at the surface layer. In addition, they are surface active, and therefore prone to adsorb on sinking particles, contributing to the C sequestration.

Comparison of modern pollen distribution between the northern and southern parts of the South China Sea.

Science.gov (United States)

Luo, Chuanxiu; Chen, Muhong; Xiang, Rong; Liu, Jianguo; Zhang, Lanlan; Lu, Jun

2015-04-01

The authors conducted a palynological analysis based on different number of air pollen samples for the northern and southern parts of the South China Sea, respectively, in order to give a reference to reconstruct the paleoclimate of the area. (1) Fifteen air pollen samples were collected from the northern part of the South China Sea from August to September 2011, and 13 air pollen samples were collected from the southern part of the South China Sea in December 2011. The pollen types were more abundant in the north than in the south. The total pollen number and concentration in the north was 10 times more than that in the south, which may be because of the sampling season. Airborne pollen types and concentrations have a close relationship with wind direction and distance from the sampling point to the continent. (2) Seventy-four samples were collected from surface sediments in the northern part of the South China Sea in the autumn. Thirty-three samples were collected from surface sediments in the southern part of the South China Sea in the winter. Pollen concentrations in the north were nearly 10 times higher than that in the south. This is because trilete spores are transported by rivers from Hainan Island to the sea and also by the summer monsoon-forced marine current. (3) Ten air pollen samples and 10 surface sediments samples were selected for comparison. The pollen and spores in the air were mainly herbaceous and woody pollen, excluding fern spores, having seasonal pollen characteristics. Pollen in the surface sediments were mainly trilete, Pinus, and herbaceous, and may also show a combination of annual pollen characteristics.

Medium-term dynamics of a middle Adriatic barred beach

Directory of Open Access Journals (Sweden)

M. Postacchini

2017-09-01

Full Text Available In recent years, attention has been paid to beach protection by means of soft and hard defenses. Along the Italian coast of the Adriatic Sea, sandy beaches are the most common landscape feature and around 70 % of the Marche region's coast (central Adriatic is protected by defense structures. The longest free-from-obstacle nearshore area in the region includes the beach of Senigallia, frequently monitored in the last decades and characterized by a multiple bar system, which represents a natural beach defense. The bathymetries surveyed in 2006, 2010, 2011, 2012 and 2013 show long-term stability, confirmed by a good adaptation of an analyzed stretch of the beach to the Dean-type equilibrium profile, though a strong short- to medium-term variability of the wave climate has been observed during the monitored periods. The medium-term dynamics of the beach, which deal with the evolution of submerged bars and are of the order of years or seasons, have been related to the wave climate collected, during the analyzed temporal windows, by a wave buoy located about 40 km off Senigallia. An overall interpretation of the hydrodynamics, sediment characteristics and seabed morphology suggests that the wave climate is fundamental for the morphodynamic changes of the beach in the medium term. These medium-term time ranges during which waves mainly come from NNE/ESE are characterized by a larger/smaller steepness and by a larger/smaller relative wave height, and seem to induce seaward/shoreward bar migration as well as bar smoothing/steepening. Moving southeastward, the bar dimension increases, while the equilibrium profile shape suggests the adaptation to a decreasing sediment size in the submerged beach. This is probably due to the presence of both the harbor jetty and river mouth north of the investigated area.

Biologic impact on the coastal belt of the province of Venice (Italy, Northern Adriatic Sea): preliminary analysis for the characterization of the bathing water profile.

Science.gov (United States)

Ostoich, Marco; Aimo, Emilia; Fassina, Daniel; Barbaro, Jvan; Vazzoler, Marina; Soccorso, Corrado; Rossi, Chiara

2011-02-01

This paper presents a preliminary study of the water profile with reference to microbiological parameters, required by Directive 2006/07/EC (European Community 2006) concerning the management of bathing water quality, in the coastal belt of the Province of Venice (Italy, Northern Adriatic Sea). A historical database has been implemented with monitoring data for the period 2000-2006 (data on rivers, bathing and marine coastal waters and on the characterization of Wastewater Treatment Plant (WWTP) discharges) from the institutional activity of Veneto Regional Environmental Prevention and Protection Agency (ARPAV). An integrated areal analysis for the microbiological investigation of homogeneous stretches along the coast of the Province of Venice was performed for a preliminary characterization of the bathing water profile considering water quality status and existing pressure sources. ARPAV is the institutional body responsible for environmental monitoring and control activities. Data were produced from monitoring and controls made available by the Regional Environmental Informative System and extracted and elaborated for the period of interest (2000-2006). Sampling and analysis of microbiological parameters were executed following the official Italian methods in accordance with international procedures (APHA et al. 1998). For the purpose of this study, the coast was divided into eight stretches, which were considered to be homogeneous according to their physical and geographical characteristics. An ANOVA statistical assessment has been performed on stretches I, V and VIII. From the integrated areal analysis of microbiological parameters in the homogeneous stretches along the coast of all the investigated matrices, high mean levels of faecal contamination were found in some cases. The most critical situation amongst the stretches evaluated is to be found in stretch VIII-Ca' Roman, Sottomarina and Isola Verde shores (Southern part of the Province). These results can

Land–sea coupling of early Pleistocene glacial cycles in the southern North Sea exhibit dominant Northern Hemisphere forcing

Directory of Open Access Journals (Sweden)

T. H. Donders

2018-03-01

Full Text Available We assess the disputed phase relations between forcing and climatic response in the early Pleistocene with a spliced Gelasian (∼ 2.6–1.8 Ma multi-proxy record from the southern North Sea basin. The cored sections couple climate evolution on both land and sea during the intensification of Northern Hemisphere glaciation (NHG in NW Europe, providing the first well-constrained stratigraphic sequence of the classic terrestrial Praetiglian stage. Terrestrial signals were derived from the Eridanos paleoriver, a major fluvial system that contributed a large amount of freshwater to the northeast Atlantic. Due to its latitudinal position, the Eridanos catchment was likely affected by early Pleistocene NHG, leading to intermittent shutdown and reactivation of river flow and sediment transport. Here we apply organic geochemistry, palynology, carbonate isotope geochemistry, and seismostratigraphy to document both vegetation changes in the Eridanos catchment and regional surface water conditions and relate them to early Pleistocene glacial–interglacial cycles and relative sea level changes. Paleomagnetic and palynological data provide a solid integrated timeframe that ties the obliquity cycles, expressed in the borehole geophysical logs, to Marine Isotope Stages (MIS 103 to 92, independently confirmed by a local benthic oxygen isotope record. Marine and terrestrial palynological and organic geochemical records provide high-resolution reconstructions of relative terrestrial and sea surface temperature (TT and SST, vegetation, relative sea level, and coastal influence.During the prominent cold stages MIS 98 and 96, as well as 94, the record indicates increased non-arboreal vegetation, low SST and TT, and low relative sea level. During the warm stages MIS 99, 97, and 95 we infer increased stratification of the water column together with a higher percentage of arboreal vegetation, high SST, and relative sea level maxima. The early Pleistocene distinct

In vivo exposure to northern diatoms arrests sea urchin embryonic development.

Science.gov (United States)

Gudimova, Elena; Eilertsen, Hans C; Jørgensen, Trond Ø; Hansen, Espen

2016-01-01

There are numerous reports indicating that marine diatoms may act harmful to early developmental stages of invertebrates. It is believed that the compounds responsible for these detrimental effects are oxylipins resulting from oxidized polyunsaturated fatty acids, and that they may function as grazing deterrents. Most studies reporting these effects have exposed test organisms to diatom extracts or purified toxins, but data from in vivo exposure to intact diatoms are scarce. We have conducted sea urchin egg incubation and plutei feeding experiments to test if intact diatom cells affected sea urchin embryo development and survival. This was done by exposing the common northern sea urchins Strongylocentrotus droebachiensis and Echinus acutus to northern strains of the diatoms Chaetoceros socialis, Skeletonema marinoi, Chaetoceros furcellatus, Attheya longicornis, Thalassiosira gravida and Porosira glacialis. The intact diatom cell suspensions were found to inhibit sea urchin egg hatching and embryogenesis. S. marinoi was the most potent one as it caused acute mortality in S. droebachiensis eggs after only four hours exposure to high (50 μg/L Chla) diatom concentrations, as well as 24 h exposure to normal (20 μg/L Chla) and high diatom concentrations. The second most potent species was T. gravida that caused acute mortality after 24 h exposure to both diatom concentrations. A. longicornis was the least harmful of the diatom species in terms of embryo development arrestment, and it was the species that was most actively ingested by S. droebachiensis plutei. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Ecological characterization of toxic phytoplankton species (Dinophysis spp., Dinophyceae) in Slovenian mariculture areas (Gulf of Trieste, Adriatic Sea) and the implications for monitoring

International Nuclear Information System (INIS)

France, Janja . E-mail france@mbss.org; Mozetic, Patricija

2006-01-01

Diarrhetic shellfish poisoning (DSP) events are often registered in Slovenian mariculture areas (Gulf of Trieste, Adriatic Sea) and are related to the occurrence of Dinophysis spp. The annual dynamic of this genus and succession of the most important species were studied at two shellfish farms during monitoring fieldwork in the period 1995-2003. Results indicate that the Dinophysis genus maintains a relatively stable inter-annual dynamic at both sites. The Dinophysis community is characterized by two surface maxima in June and September, while in the middle layer only the autumn peak is pronounced (peak median 92 cells l -1 ). Occasional abundance maxima of around 2000 cells l -1 in the surface layer indicate that potential outbursts of toxic species are less predictable than their seasonal dynamic. On the basis of multivariate analysis, Dinophysis sacculus was characterized as a typical late spring-early summer species, and Dinophysis caudata and Dinophysis fortii as autumn species. Correlation analysis revealed the influence of stratified conditions only on the most abundant species, D. sacculus. Ecological characteristics of the species were combined with shellfish safety requirements towards a more effective monitoring

CRITERIA OF THE ECOSYSTEM STABILITY IN THE NORTHERN REGION OF THE CASPIAN SEA

Directory of Open Access Journals (Sweden)

Natalia Mitina

2011-01-01

Full Text Available The aim of the work is to determine the criteria of the marine shallow-water ecosystem stability using the Northern region of the Caspian Sea as a case study. For each 260 reference points, we received data on 76 parameters, including physical-geographical, hydrochemical, and hydrobiological characteristics that have been analyzed by the method of principle components. The analyzes of these data allowed us to reveal and evaluate principal geoecological factors that influence the distribution of Acipenseridae in the Caspian Sea as a top level of the ecosystem’s trophic chain. The main geoecological factors and the factor of anthropogenic load of the Caspian Sea ecosystems’ stability have been determined.

Metals in Blood and Eggs of Green Sea Turtles (Chelonia mydas) from Nesting Colonies of the Northern Coast of the Sea of Oman.

Science.gov (United States)

Sinaei, Mahmood; Bolouki, Mehdi

2017-11-01

The green sea turtle (Chelonia mydas) has been a species of global concern for decades. In this study, heavy metals (mercury: Hg; Cadmium: Cd; Lead: Pb; Copper: Cu; and Zinc: Zn) were measured in blood and three egg fraction of green sea turtles nesting on the northern coast of Sea of Oman. Heavy metals concentrations in blood, yolk, albumen, and egg shell ranged between 0.16-36.78, 0.006-33.88, 0.003-4.02, and 0.002-6.85 μg/g (ww), respectively. According to the results, all heavy metals found in blood samples (n = 12) also were detected in the various parts of the eggs (n = 48). Moreover, there were no significant differences between concentrations of heavy metals in different clutches laid in a nesting season. However, Pb concentrations in blood samples significantly increased in later clutches (p Oman. Results of this study suggest that heavy metals could be one of the factors influencing reductions in fertilization and hatching success. Results also indicate that green sea turtle on the northern coast of Sea of Oman have high capacity in rapid response and detoxification of heavy metals and/or from the low exposure levels of these turtles to the heavy metals. Further research is required concerning the effects of heavy metals on green sea turtles, especially on their possible influence of fetal development of turtles.

Overview of 2010-2013 spring campaigns of Seven South East Asian Studies (7-SEAS) in the northern Southeast Asia

Science.gov (United States)

Lin, N.; Tsay, S.; Hsu, N. C.; Holben, B. N.; Anh, N.; Reid, J. S.; Sheu, G.; Chi, K.; Wang, S.; Lee, C.; Wang, L.; Wang, J.; Chen, W.; Welton, E. J.; Liang, S.; Sopajaree, K.; Maring, H. B.; Janjai, S.; Chantara, S.

2013-12-01

The Seven South East Asian Studies (7-SEAS) is a grass-root program and seeks to perform interdisciplinary research in the field of aerosol-meteorology and climate interaction in the Southeast Asian region, particularly for the impact of biomass burning on cloud, atmospheric radiation, hydrological cycle, and regional climate. Participating countries include Indonesia, Malaysia, Philippines, Singapore, Thailand, Taiwan, Vietnam, and USA. A series of field experiments have been conducted during springtime biomass burning seasons in northern Southeast Asia, i.e., Dongsha Experiment in 2010, Son La Campaigns in 2011 and 2012, and BASELInE (Biomass-burning Aerosols & Stratocumulus Environment: Lifecycles and Interactions Experiment) in 2013, respectively. Given an example, during 2010 Dongsha Experiment, a monitoring network for ground-based measurements was established, including five stations from northern Thailand and central Vietnam to Taiwan, with a supersite at the Dongsha Island (i.e. Pratas Island) in South China Sea (or East Sea). Aerosol chemistry sampling was performed for each station for characterizing the compositions of PM2.5/PM10 (some for TSP) including water-soluble ions, metal elements, BC/OC, Hg and dioxins. This experiment provides a relatively complete and first dataset of aerosol chemistry and physical observations conducted in the source/sink region for below marine boundary layer and lower free troposphere of biomass burning/air pollutants in the northern SE Asia. This presentation will give an overview of these 7-SEAS activities and their results, particularly for the characterization of biomass-burning aerosol at source regions in northern Thailand and northern Vietnam, and receptor stations in Taiwan, which is rarely studied.

Carbon cycling in the northern Arabian Sea during the northeast monsoon: Significance of salps

Digital Repository Service at National Institute of Oceanography (India)

Naqvi, S.W.A.; Sarma, V.V.S.S.; Jayakumar, D.A.

Winter cooling and mixing brings nutrients (nitrate and phosphate) to the surface waters over large parts of the northern Arabian Sea, but the rates of primary production as well as carbon export from the euphotic zone are not especially high during...

The North Sea field development guide. V.1: Northern North Sea. V.2: Southern North Sea. 6. ed.

International Nuclear Information System (INIS)

Anon.

1996-08-01

The 1997/8, sixth edition is the first to be divided into two volumes. Volume 1 covers the central and northern North Sea areas; volume 2 contains the southern North Sea as well as the Irish and German sectors. The pages are numbered consecutively over the two volumes, with page numbers greater than 702 contained in the second volume. There are three index sections. Main index. Arranged by national sector (UK, Norway etc.) Within each sector the entries are alphabetical by operator name. This index contains page numbers for the book entries: the other two index sections should be used with the main index to find the exact location of an entry; Index by field. If the reader knows a field name (e.g. Kittiwake) but not the operator or the national sector, this index will reference them; Index by installation. Each installation (''Fulmar SALM'', ''Togi'') is named, giving the operator, field and national sector where it is located. This index is also useful for locating particular kinds of installations, such as subsea completions; The book is intended to provide a factual overview of field development activity in the North Sea (a term loosely used to include the Irish Sea and the Baltic Sea). The aim is therefore to provide some background, specifications and history on every offshore installation in that area. Speculative or evaluative commentary is avoided where possible. No attempt has been made to forecast the form or probability of future developments, except in those few instances where announcements have been made by the oil company itself, and these are, clearly indicated. (UK)

Genetic population structure of the lionfish Pterois miles (Scorpaenidae, Pteroinae) in the Gulf of Aqaba and northern Red Sea.

Science.gov (United States)

Kochzius, Marc; Blohm, Dietmar

2005-03-14

The aim of this study is to reveal gene flow between populations of the coral reef dwelling lionfish Pterois miles in the Gulf of Aqaba and northern Red Sea. Due to the fjord-like hydrography and topology of the Gulf of Aqaba, isolation of populations might be possible. Analysis of 5' mitochondrial control region sequences from 94 P. miles specimens detected 32 polymorphic sites, yielding 38 haplotypes. Sequence divergence among different haplotypes ranged from 0.6% to 9.9% and genetic diversity was high (h=0.85, pi=1.9%). AMOVA indicates panmixia between the Gulf of Aqaba and northern Red Sea, but analysis of migration pattern shows an almost unidirectional migration originating from the Red Sea.

Air-sea exchange of CO2 in the Gulf of Kutch, northern Arabian Sea based on bomb-carbon in corals and tree rings

International Nuclear Information System (INIS)

Chakraborty, S.; Ramesh, R.; Krishnaswami, S.

1994-01-01

Radiocarbon analyses were carried out in the annual bands of a 40 year old coral collected from the Gulf of Kutch (22.6degN, 70degE) in the northern Arabian Sea and in the annual rings of a teak tree from Thane (19deg14'N, 73deg24'E) near Bombay. These measurements were made in order to obtain the rates of air-sea exchange of CO 2 and the advective mixing of water in the Gulf of Kutch. The Δ 14 C peak in the Thane tree occurs in the year 1964, with a value of ∼630 part per thousand, significantly lower than that of the mean atmospheric Δ 14 C of the northern hemisphere (∼1000 part per thousand). The radiocarbon time series of the coral was modelled considering the supply of carbon and radiocarbon to the gulf through air-sea exchange and advective water transport from the open Arabian Sea. A reasonable fit for the coral data was obtained with an air-sea CO 2 exchange rate of 11-12 mol m -2 yr -1 , and an advective velocity of 28 m yr -1 between the Arabian Sea and the Gulf of Kutch; this was based on a model generated time series for radiocarbon in the Arabian Sea. The deduced velocity (∼ 28 m yr -1 ) of the advective transport of water between the Gulf and the Arabian Sea is much lower than the surface tidal current velocity in this region, but can be understood in terms of net fluxes of carbon and radiocarbon to the gulf to match the observed coral Δ 14 C time series. (author). 30 refs., 7 figs., 2 tabs

Prevalence of Corynosoma caspicum infection in Gasterosteus aculeatus fish in Caspian Sea, Northern Iran.

Science.gov (United States)

Rahimi-Esboei, Bahman; Najm, Mahdi; Shaker, Morad; Fakhar, Mahdi; Mobedi, Iraj

2017-09-01

There is little information about the prevalence of Corynosoma caspicum in fish particularly Gasterosteus aculeatus in Iran and the world. The aim of the present study was to find out the prevalence of acanthocephalan infection in Babolsar district, southern coastal of Caspian Sea, Northern Iran. Between September 2012 and August 2014, a total of 360 G. aculeatus fishes were randomly collected by drift nets from coastal regions in Babolsar and then examined the intestine and body cavity for worm infections. A total of 360 G. aculeatus fishes, 109 (30.3%) were found infected with at least one Corynosoma capsicum , and there was no significant association between genders and the prevalence infection of acanthocephalan. Moreover, there was a significant difference in infected rate between summer (79%, 86/109) and spring (21%, 23/109) (paculeatus indicates the enzootic constancy status of the infection in the southern coastal of Caspian Sea, Northern Iran.

Refining aging criteria for northern sea otters in Washington State

Science.gov (United States)

Schuler, Krysten L.; Baker, Bridget B.; Mayer, Karl A.; Perez-Heydrich, Carolina; Holahan, Paula M.; Thomas, Nancy J.; White, C. LeAnn

2018-01-01

Measurement of skull ossification patterns is a standard method for aging various mammalian species and has been used to age Russian, Californian, and Alaskan sea otter populations. Cementum annuli counts have also been verified as an accurate aging method for the Alaskan sea otter population. In this study, cementum annuli count results and skull ossification patterns were compared as methods for aging the northern sea otter (Enhydra lutris kenyoni) population in Washington State. Significant agreement was found between the two methods suggesting that either method could be used to age the Washington population of otters. This study also found that ossification of the squamosal-jugal suture at the ventral glenoid fossa can be used to differentiate male subadults from adults. To assist field biologists or others without access to cementum annuli or skull ossification analysis techniques, a suite of morphologic, physiologic, and developmental characteristics were analyzed to assess whether a set of these more easily accessible parameters could also predict age class for the Washington population of otters. Tooth condition score, evidence of reproductive activity in females, and tooth eruption pattern were identified as the most useful criteria for classifying Washington sea otters as pups, juveniles, subadults, or adults/aged adults. A simple decision tree based on characteristics accessible in the field or at necropsy was created that can be used to reliably predict age class of Washington sea otters as determined by cementum annuli.

Strong copper(II) species in estuarine and sea waters investigated by a method with high detection window.

Science.gov (United States)

Alberti, Giancarla; Biesuz, Raffaela; D'Agostino, Girolamo; Scarponi, Giuseppe; Pesavento, Maria

2007-02-15

The distribution of copper(II) in species of different stability in some estuarine and sea water samples (Adriatic Sea) was investigated by a method based on the sorption of the metal ion on a strongly sorbing resin, Chelex 100, whose sorbing properties have been previously characterized. From them, it is possible to predict very high values of detection windows at the considered conditions, for example side reaction coefficient as high as 10(10) at pH 7.5. Strong copper(II) species in equilibrium with Chelex 100 were detected, at concentration 2-20nM, with a reaction coefficient approximately 10(10.6) at pH 7.45 in sea water, strictly depending on the acidity. They represent 50-70% of the total metal ion and are the strongest copper(II) complexes found in sea water. Weak complexes too were detected in all the samples, with reaction coefficient lower than ca. 10(9) at the same pH. The method applied, named resin titration (RT), was described in a previous investigation, and is here modified in order to be carried out on oceanographic boat during a cruise in the Adriatic Sea.

Long-term spatiotemporal trends and health risk assessment of oyster arsenic levels in coastal waters of northern South China Sea.

Science.gov (United States)

Wang, Xuefeng; Wang, Lifei; Jia, Xiaoping; Jackson, Donald A

2017-09-01

Long-term spatiotemporal trends and health risk assessment of oyster arsenic levels in the coastal waters of northern South China Sea were investigated in order to help improve the quality and safety control and sustainable aquaculture for mollusks in China. Cultured oysters (Crassostrea rivularis) collected from the waters of 23 bays, harbors, and estuaries along the coast of northern South China Sea from 1989 to 2012 were examined for spatial patterns and long-term temporal trends of oyster arsenic levels. Single-factor index and health risk assessment were used to quantify arsenic exposure to human health through oyster consumption. Overall, arsenic was detected in 97.4% of the oyster samples, and oyster arsenic levels were non-detectable-2.51 mg/kg with an average of 0.63 ± 0.54 mg/kg. Oyster arsenic levels in the coastal waters of northern South China Sea showed an overall decline from 1989 to 2012, remained relatively low since 2005, and slightly increased after 2007. Oyster arsenic levels in Guangdong coastal waters were much higher with more variation than in Guangxi and Hainan coastal waters, and the long-term trends of oyster arsenic levels in Guangdong coastal waters dominated the overall trends of oyster arsenic levels in the coastal waters of northern South China Sea. Within Guangdong Province, oyster arsenic levels were highest in east Guangdong coastal waters, followed by the Pearl River estuary and west Guangdong coastal waters. Single-factor index ranged between 0.27 and 0.97, and average health risk coefficient was 3.85 × 10 -5 , both suggesting that oyster arsenic levels in northern South China Sea are within the safe range for human consumption. However, long-term attention should be given to seafood market monitoring in China and the risk of arsenic exposure to human health through oyster consumption.

Monitoring plastic ingestion by the northern fulmar Fulmarus glacialis in the North Sea

NARCIS (Netherlands)

Franeker, van J.A.; Blaize, C.; Danielsen, J.

2011-01-01

The abundance of plastics in stomachs of northern fulmars from the North Sea is used in the OSPAR Ecological Quality Objective (EcoQO) for marine litter. The preliminary EcoQO defines acceptable ecological quality as the situation where no more than 10% of fulmars exceed a critical level of 0.1 g of

Phocine Distemper Virus in Northern Sea Otters in the Pacific Ocean, Alaska, USA

Science.gov (United States)

Mazet, Jonna A.K.; Gill, Verena A.; Doroff, Angela M.; Burek, Kathy A.; Hammond, John A.

2009-01-01

Phocine distemper virus (PDV) has caused 2 epidemics in harbor seals in the Atlantic Ocean but had never been identified in any Pacific Ocean species. We found that northern sea otters in Alaska are infected with PDV, which has created a disease threat to several sympatric and decreasing Pacific marine mammals. PMID:19523293

Monitoring plastic ingestion by the northern fulmar Fulmarus glacialis in the North Sea

Energy Technology Data Exchange (ETDEWEB)

Franeker, Jan A. van, E-mail: Jan.vanfraneker@wur.nl [IMARES Institute for Marine Resources and Ecosystem Studies, Wageningen-UR, PO Box 167, 1790AD Den Burg, Texel (Netherlands); Blaize, Christine [Le CHENE, Centre de Sauvegarde de la Faune Sauvage et Musee de la Nature, 12 Rue du Musee, F-76190 Allouville-Bellefosse (France); Danielsen, Johannis [Norouri i Sundum 7, FO-410 Kollafjorour (Faroe Islands); Fairclough, Keith [Fairclough Ecological Orkney FEO Viewforth, Swannay by Evie, Orkney, KW17 2NR, Scotland (United Kingdom); Gollan, Jane [Kermouroux, FR-56 470 Saint Philibert (France); Guse, Nils [Research and Technology Centre West coast FTZ, University of Kiel, Hafentoern 1, D-25761 Buesum (Germany); Hansen, Poul-Lindhard [Naturhistorisk Museum Skagen, Skagen Naturcenter, Flagbakkevej 30, DK-9990 Skagen (Denmark); Heubeck, Martin [University of Aberdeen (SOTEAG), Sumburgh Head Lighthouse, Virkie, Shetland ZE3 9JN, Scotland (United Kingdom); Jensen, Jens-Kjeld [Zoological conservator, I Geilini 37, FO-270 Nolsoy (Faroe Islands); Le Guillou, Gilles [Groupe Ornithologique Normand, 118 route d' ORCHER, F-76700 Gonfreville l' Orcher (France); Olsen, Bergur [Faroe Marine Research Institute c/o Natturugripasavnio, Futalag 40, FO-100 Torshavn (Faroe Islands); Olsen, Kare-Olav [Postveien 43, N-4563 Borhaug (Norway); Pedersen, John [Skagen Uddannelsescenter SUC, Vestmolen 15, DK-9990 Skagen (Denmark); Stienen, Eric W.M. [Research Institute for Nature and Forest, Kliniekstraat 25, B-1070 Brussels (Belgium); Turner, Daniel M. [9 Haswell Gardens, North Shields, Tyne and Wear, NE30 2DP, England (United Kingdom)

2011-10-15

The abundance of plastics in stomachs of northern fulmars from the North Sea is used in the OSPAR Ecological Quality Objective (EcoQO) for marine litter. The preliminary EcoQO defines acceptable ecological quality as the situation where no more than 10% of fulmars exceed a critical level of 0.1 g of plastic in the stomach. During 2003-2007, 95% of 1295 fulmars sampled in the North Sea had plastic in the stomach (on average 35 pieces weighing 0.31 g) and the critical level of 0.1 g of plastic was exceeded by 58% of birds, with regional variations ranging from 48 to 78%. Long term data for the Netherlands since the 1980s show a decrease of industrial, but an increase of user plastics, with shipping and fisheries as the main sources. The EcoQO is now also used as an indicator for Good Environmental Status in the European Marine Strategy Framework Directive. - Highlights: > Trends in marine debris can be monitored by plastics in stomachs of seabirds. > In the North Sea 95% of Fulmars has plastic in the stomach (35 particles; 0.31 g). > The policy target is that less than 10% of Fulmars has over 0.1 g of plastic. > Currently 58% of North Sea fulmars exceeds the 0.1 g critical limit. > Over the past 30 years industrial plastics decreased and user plastic increased. - Trends and patterns in the abundance of plastics in northern fulmar stomachs show that seabirds can be a valuable tool for monitoring marine litter.

Monitoring plastic ingestion by the northern fulmar Fulmarus glacialis in the North Sea

International Nuclear Information System (INIS)

Franeker, Jan A. van; Blaize, Christine; Danielsen, Johannis; Fairclough, Keith; Gollan, Jane; Guse, Nils; Hansen, Poul-Lindhard; Heubeck, Martin; Jensen, Jens-Kjeld; Le Guillou, Gilles; Olsen, Bergur; Olsen, Kare-Olav; Pedersen, John; Stienen, Eric W.M.; Turner, Daniel M.

2011-01-01

The abundance of plastics in stomachs of northern fulmars from the North Sea is used in the OSPAR Ecological Quality Objective (EcoQO) for marine litter. The preliminary EcoQO defines acceptable ecological quality as the situation where no more than 10% of fulmars exceed a critical level of 0.1 g of plastic in the stomach. During 2003-2007, 95% of 1295 fulmars sampled in the North Sea had plastic in the stomach (on average 35 pieces weighing 0.31 g) and the critical level of 0.1 g of plastic was exceeded by 58% of birds, with regional variations ranging from 48 to 78%. Long term data for the Netherlands since the 1980s show a decrease of industrial, but an increase of user plastics, with shipping and fisheries as the main sources. The EcoQO is now also used as an indicator for Good Environmental Status in the European Marine Strategy Framework Directive. - Highlights: → Trends in marine debris can be monitored by plastics in stomachs of seabirds. → In the North Sea 95% of Fulmars has plastic in the stomach (35 particles; 0.31 g). → The policy target is that less than 10% of Fulmars has over 0.1 g of plastic. → Currently 58% of North Sea fulmars exceeds the 0.1 g critical limit. → Over the past 30 years industrial plastics decreased and user plastic increased. - Trends and patterns in the abundance of plastics in northern fulmar stomachs show that seabirds can be a valuable tool for monitoring marine litter.

Polar bear population status in the northern Beaufort Sea, Canada, 1971-2006.

Science.gov (United States)

Stirling, Ian; McDonald, Trent L; Richardson, E S; Regehr, Eric V; Amstrup, Steven C

2011-04-01

Polar bears (Ursus maritimus) of the northern Beaufort Sea (NB) population occur on the perimeter of the polar basin adjacent to the northwestern islands of the Canadian Arctic Archipelago. Sea ice converges on the islands through most of the year. We used open-population capture-recapture models to estimate population size and vital rates of polar bears between 1971 and 2006 to: (1) assess relationships between survival, sex and age, and time period; (2) evaluate the long-term importance of sea ice quality and availability in relation to climate warming; and (3) note future management and conservation concerns. The highest-ranking models suggested that survival of polar bears varied by age class and with changes in the sea ice habitat. Model-averaged estimates of survival (which include harvest mortality) for senescent adults ranged from 0.37 to 0.62, from 0.22 to 0.68 for cubs of the year (COY) and yearlings, and from 0.77 to 0.92 for 2-4 year-olds and adults. Horvtiz-Thompson (HT) estimates of population size were not significantly different among the decades of our study. The population size estimated for the 2000s was 980 +/- 155 (mean and 95% CI). These estimates apply primarily to that segment of the NB population residing west and south of Banks Island. The NB polar bear population appears to have been stable or possibly increasing slightly during the period of our study. This suggests that ice conditions have remained suitable and similar for feeding in summer and fall during most years and that the traditional and legal Inuvialuit harvest has not exceeded sustainable levels. However, the amount of ice remaining in the study area at the end of summer, and the proportion that continues to lie over the biologically productive continental shelf (polar bear population in the northern Beaufort Sea will eventually decline. Management and conservation practices for polar bears in relation to both aboriginal harvesting and offshore industrial activity will need to

Polar bear population status in the northern Beaufort Sea, Canada, 1971-2006

Science.gov (United States)

Stirling, I.; McDonald, T.L.; Richardson, E.S.; Regehr, E.V.; Amstrup, Steven C.

2011-01-01

Polar bears (Ursus maritimus) of the northern Beaufort Sea (NB) population occur on the perimeter of the polar basin adjacent to the northwestern islands of the Canadian Arctic Archipelago. Sea ice converges on the islands through most of the year. We used open-population capture–recapture models to estimate population size and vital rates of polar bears between 1971 and 2006 to: (1) assess relationships between survival, sex and age, and time period; (2) evaluate the long-term importance of sea ice quality and availability in relation to climate warming; and (3) note future management and conservation concerns. The highest-ranking models suggested that survival of polar bears varied by age class and with changes in the sea ice habitat. Model-averaged estimates of survival (which include harvest mortality) for senescent adults ranged from 0.37 to 0.62, from 0.22 to 0.68 for cubs of the year (COY) and yearlings, and from 0.77 to 0.92 for 2–4 year-olds and adults. Horvtiz-Thompson (HT) estimates of population size were not significantly different among the decades of our study. The population size estimated for the 2000s was 980 ± 155 (mean and 95% CI). These estimates apply primarily to that segment of the NB population residing west and south of Banks Island. The NB polar bear population appears to have been stable or possibly increasing slightly during the period of our study. This suggests that ice conditions have remained suitable and similar for feeding in summer and fall during most years and that the traditional and legal Inuvialuit harvest has not exceeded sustainable levels. However, the amount of ice remaining in the study area at the end of summer, and the proportion that continues to lie over the biologically productive continental shelf (polar bear population in the northern Beaufort Sea will eventually decline. Management and conservation practices for polar bears in relation to both aboriginal harvesting and offshore industrial activity will need

Climate warming and interannual variability of phytoplankton phenology in the Northern Red Sea

KAUST Repository

Gittings, John

2016-12-01

In agreement with global patterns of climate change and increasing temperatures in the tropical oceans, the Northern Red Sea (NRS) has been warming over the last few decades. Using 18 years of remotely-sensed chlorophyll-a data (Chl-a, an index of phytoplankton biomass), we investigate the potential impacts of climate warming on phytoplankton abundance and phenology in the Northern Red Sea by exploring the mechanistic links with the regional physical environment. The results of the analysis reveal that, in accordance with other tropical ecosystems, phytoplankton biomass in the NRS will decrease in response to warmer climate scenarios. This is attributed to lower heat fluxes (heat loss to the atmosphere) during the bloom period, and enhanced vertical stratification, which prevents vertical mixing of nutrients into the euphotic layer. In addition, we show that during warmer conditions (when heat fluxes are weakened), the winter bloom initiates significantly later (by up to 10 weeks) and its duration is considerably reduced. The biological implications of alterations to phytoplankton phenology may include increased larval mortality of pelagic species, reduced recruitment, fisheries impacts and changes to community structure.

Effect of the Northern Sea Route Opening to the Shipping Activities at Malacca Straits

Directory of Open Access Journals (Sweden)

N.S.F. Abdul Rahman

2014-12-01

Full Text Available The opening of the Northern Sea Route as an alternative route for transporting cargoes between the Far East and Europe seems highly acceptable by shipping companies due to the great saving in fuel consumption, bunker cost, operating cost, emissions and journey time. This situation will not only affect the maritime business activity in the Straits of Malacca but also, the Malaysian economy in different perspectives when the vessels sail via the Suez Canal and the Indian Ocean are expected to decrease. The objective of this study is to analyse the implication in the opening of the Northern Sea Route on Maritime Sector of the Malaysian economy by using PESTEL analysis. The main scope is focusing more on the Malacca Straits shipping activity by using a number of parameters that have been obtained from Port Klang and Port Klang Authority through a set of questionnaires and interview sessions with industrial experts.

The characteristics of heat flow in the Shenhu gas hydrate drilling area, northern South China Sea

Science.gov (United States)

Xu, Xing; Wan, Zhifeng; Wang, Xianqing; Sun, Yuefeng; Xia, Bin

2016-12-01

Marine heat flow is of great significance for the formation and occurrence of seabed oil, gas and gas hydrate resources. Geothermal gradient is an important parameter in determining the thickness of the hydrate stability zone. The northern slope of the South China Sea is rich in gas hydrate resources. Several borehole drilling attempts were successful in finding hydrates in the Shenhu area, while others were not. The failures demand further study on the distribution regularities of heat flow and its controlling effects on hydrate occurrence. In this study, forty-eight heat flow measurements are analyzed in the Shenhu gas hydrate drilling area, located in the northern South China Sea, together with their relationship to topography, sedimentary environment and tectonic setting. Canyons are well developed in the study area, caused mainly by the development of faults, faster sediment supply and slumping of the Pearl River Estuary since the late Miocene in the northern South China Sea. The heat flow values in grooves, occurring always in fault zones, are higher than those of ridges. Additionally, the heat flow values gradually increase from the inner fan, to the middle fan, to the external fan subfacies. The locations with low heat flow such as ridges, locations away from faults and the middle fan subfacies, are more conducive to gas hydrate occurrence.

Coastal sea level response to the tropical cyclonic forcing in the northern Indian Ocean

Digital Repository Service at National Institute of Oceanography (India)

Mehra, P.; Soumya, M.; Vethamony, P.; Vijaykumar, K.; Nair, T.M.B.; Agarvadekar, Y.; Jyoti, K.; Sudheesh, K.; Luis, R.; Lobo, S.; Halmalkar, B.

–173, 2015 www.ocean-sci.net/11/159/2015/ doi:10.5194/os-11-159-2015 © Author(s) 2015. CC Attribution 3.0 License. Coastal sea level response to the tropical cyclonic forcing in the northern Indian Ocean P. Mehra1, M. Soumya1, P. Vethamony1, K. Vijaykumar1, T.... Note: sea level data at Colombo, Kochi, Karachi, Chabahar, Jask, Masirah, Minocoy and Hanimaadhoo are downloaded from www.gloss-sealevel.org and are shown with red stars. (Time is in Indian standard time (IST).) land locations of India are provided...

Seasonal variability of thermal fronts in the northern South China Sea from satellite data

Science.gov (United States)

Wang, Dongxiao; Liu, Yun; Qi, Yiquan; Shi, Ping

The 8-year (1991-1998) Pathfinder sea surface temperature data have been applied here to produce the objectively derived seasonality of the oceanic thermal fronts in the northern South China Sea from 17°N to 25°N. Several fronts have been clearly distinguished, namely, Fujian and Guangdong Coastal Water, Pear River Estuary Coastal, Taiwan Bank, Kuroshio Intrusion, Hainan Island East Coast and Tonkin Gulf Coastal fronts. The frontal patterns in winter, spring and summer are quite similar, whereas individual fronts display different modes of seasonal variability due to different mechanisms favoring those fronts.

Carbon dioxide in northern high latitude oceans: Anthropogenic increase and air-sea flux variability

Energy Technology Data Exchange (ETDEWEB)

Omar, Abdirahman M.

2003-07-01

The aim of this thesis is to further our knowledge of carbon dioxide in the northern high latitude oceans (northern North Atlantic, Barents Sea, and Arctic Ocean) by studying the anthropogenic change in the oceanic CO2, the inter-annual variability of the air-sea CO2 flux, and the relationship between this variability and changes in other oceanic processes. An introductory chapter and four papers are presented. Descriptions of the seawater carbonate system parameters, air-sea exchange of CO2, and related processes are given in the introduction chapter. The anthropogenic increase in partial pressure of CO2 (pCO2) in the surface water of the Barents Sea is evaluated in paper I. The effect of alternations of the Barents Sea climate between cold and warm modes on the annual cycles of seawater fugacity and air-sea flux of CO2 is investigated in paper II. Oceanic uptake of atmospheric CO2 associated with the seasonal formation of sea ice in Storfjorden and the implication for the entire Arctic Ocean is studied in paper III. An assessment of the variations of the air-sea flux of CO2 in the northern North Atlantic for 20 winters (1981-2001) is carried out in paper IV. PCO2 in the surface water of the Barents Sea is shown to have increased parallel with the atmospheric pCO2 between 1967 and 2000-2001 (paper I). This was determined by comparing seawater pCO2 from 1967 with that from 2000-2001. The former was estimated from surface seawater temperature (SST) while the latter was computed from data of total dissolved inorganic carbon and alkalinity. A procedure which accounts for the natural variability was applied and the difference between seawater pC02 of 1967 and that of 2000-2001 is attributed to the uptake of excess CO2. In the Atlantic sector of the Barents Sea, the surface seawater fugacity of CO2 (fCO s''w) is shown to be lower than the atmospheric fCO2 throughout the year, implying that the area is an annual sink of atmospheric CO2 (paper II). Additionally

Carbon dioxide in northern high latitude oceans: Anthropogenic increase and air-sea flux variability

International Nuclear Information System (INIS)

Omar, Abdirahman M.

2003-01-01

The aim of this thesis is to further our knowledge of carbon dioxide in the northern high latitude oceans (northern North Atlantic, Barents Sea, and Arctic Ocean) by studying the anthropogenic change in the oceanic CO2, the inter-annual variability of the air-sea CO2 flux, and the relationship between this variability and changes in other oceanic processes. An introductory chapter and four papers are presented. Descriptions of the seawater carbonate system parameters, air-sea exchange of CO2, and related processes are given in the introduction chapter. The anthropogenic increase in partial pressure of CO2 (pCO2) in the surface water of the Barents Sea is evaluated in paper I. The effect of alternations of the Barents Sea climate between cold and warm modes on the annual cycles of seawater fugacity and air-sea flux of CO2 is investigated in paper II. Oceanic uptake of atmospheric CO2 associated with the seasonal formation of sea ice in Storfjorden and the implication for the entire Arctic Ocean is studied in paper III. An assessment of the variations of the air-sea flux of CO2 in the northern North Atlantic for 20 winters (1981-2001) is carried out in paper IV. PCO2 in the surface water of the Barents Sea is shown to have increased parallel with the atmospheric pCO2 between 1967 and 2000-2001 (paper I). This was determined by comparing seawater pCO2 from 1967 with that from 2000-2001. The former was estimated from surface seawater temperature (SST) while the latter was computed from data of total dissolved inorganic carbon and alkalinity. A procedure which accounts for the natural variability was applied and the difference between seawater pC02 of 1967 and that of 2000-2001 is attributed to the uptake of excess CO2. In the Atlantic sector of the Barents Sea, the surface seawater fugacity of CO2 (fCO s''w) is shown to be lower than the atmospheric fCO2 throughout the year, implying that the area is an annual sink of atmospheric CO2 (paper II). Additionally, changes

Composition and qualitative characteristics of virgin olive oils produced in northern Adriatic region, Republic of Croatia

Directory of Open Access Journals (Sweden)

Milin, Cedomila

2001-12-01

Full Text Available Istria and Island Krk are located in the Northern Adriatic region, Republic of Croatia. The majority of oils produced on the islands of this Region correspond to extra virgin classification as a consequence of olive cultivars (Debela, Naska, Rosulja, Slatka, Buza, Carbonera, Bianchera, Leccino. The characterisation of these oils is little known. The objective of this work was the characterisation of virgin olive oils during the 1997/98, 1998/99 and six months of 1999/2000 harvest. Acidity, peroxide value and UV absorption constants were determined for all samples. Fatty acid composition, sterol and aliphatic alcohol contents, saturated fatty acids in the 2-position of the triglyceride and trilinolein content were determined for the virgin olive oils during 1997/98 harvest. The chemical analyses were supported by the determination of polyphenol content expressed as caffeic acid, squalene and α-tocopherol content.Istria y la isla Krk están localizadas en el norte de la región Adriática, República de Croacia. La mayoría de los aceites producidos en las islas de esta región corresponden a la clasificación extra virgen de las variedades (Debela, Naska, Rosulja, Slatka, Buza, Carbonera, Bianchera, Leccino. La caracterización de estos aceites es poco conocida. El objetivo de este trabajo fue la caracterización de los aceites de oliva vírgenes durante las campañas 1997/98, 1998/99 y seis meses de 1999/2000. Para todas las muestras se determinó la acidez, el índice de peróxido y las constantes de absorción en el UV. Para los aceites de oliva vírgenes durante la campaña 1997/98 se determinaron la composición en ácidos grasos, los contenidos en esteroles y alcoholes alifáticos, los ácidos grasos saturados en posición 2 de los triglicéridos y el contenido en trilinoleína. Los análisis químicos se completaron con la determinación del contenido en polifenoles expresado como ácido cafeico, y la determinación de escualeno y α-tocoferol.

A comparison of the physics of the northern and southern shelves of the eastern Bering Sea and some implications for the ecosystem

Science.gov (United States)

Stabeno, Phyllis J.; Farley, Edward V., Jr.; Kachel, Nancy B.; Moore, Sue; Mordy, Calvin W.; Napp, Jeffrey M.; Overland, James E.; Pinchuk, Alexei I.; Sigler, Michael F.

2012-06-01

Sufficient oceanographic measurements have been made in recent years to describe the latitudinal variation in the physics of the eastern Bering Sea shelf and the potential impact of climate change on the species assemblages in the two ecosystems (north and south). Many of the predicted ecosystem changes will result from alterations in the timing and extent of sea ice. It is predicted that the sea ice in the northern Bering Sea will be less common in May, but will continue to be extensive through April. In contrast, the southern shelf will have, on average, much less sea ice than currently observed, but with large interannual and multiyear variability until at least 2050. Thus, even under current climate warming scenarios, bottom temperatures on the northern shelf will remain cold. Based on biophysical measurements, the southern and northern ecosystems were divided by a North-South Transition at ˜60°N. The northern middle shelf was characterized by a freshwater lens at the surface, cold bottom temperatures, and a thicker pycnocline than found on the southern shelf. Subsurface phytoplankton blooms were common. In contrast, the southern shelf stratification was largely determined by temperature alone; the pycnocline was thin (oftenstomias, respectively) are unlikely to become common in the north. The projected warming of the southern shelf will limit the distribution of arctic species (e.g., snow crab, Chionoecetes opilio) to the northern shelf and will likely permit expansion of subarctic species into the southern Bering Sea. The distribution and abundance of baleen whales will respond to shifts in prey availability; for instance, if prey are advected northward from the southeastern Bering Sea, an extension of range and an increase in seasonally migratory baleen whale numbers is anticipated. Thus, alteration of this ecosystem in response to climate change is expected to result in something other than a simple northward shift in the distribution of all species.

Trawl catch composition during different fishing intensity periods in two Mediterranean demersal fishing grounds

Directory of Open Access Journals (Sweden)

Pilar Sánchez

2007-12-01

Full Text Available The study was carried out in two fishing grounds on the Mediterranean continental shelf: one in the Adriatic Sea and one in the Catalan Sea. Samplings on board otter trawlers were performed from November 2002 to December 2003 in the Catalan Sea and from February 2003 to January 2004 in the Adriatic Sea. The Adriatic fishing ground was affected by high fishing intensity from January to June, while the Catalan area was highly exploited from September to February. Fishing activity in the Adriatic area was closed for 45 days, and 62 days in the Catalan area; both periods were in summer. Totals of 92 and 88 species were collected in the Adriatic and Catalan fishing grounds respectively. The species composition of the retained and discarded fractions showed close agreement between the two areas. Mullus barbatus showed very low discard rates in both areas, as well as Loligo vulgaris in the Catalan Sea and Merluccius merluccius in the Adriatic Sea. In both fishing grounds Squilla mantis showed high catch rates with low discards, except in March in the Catalan area. In the Adriatic Sea Liocarcinus depurator was characterized by large discard fractions. In both fishing grounds the retained fraction was slightly higher in the high fishing intensity periods than in the low intensity ones (Adriatic Sea: 0.613 vs 0.524; Catalan Sea: 0.597 vs 0.539, even though the Kruskall Wallis test revealed significant differences (p

Different Histories, Different Destinies‒Impact of Evolutionary History and Population Genetic Structure on Extinction Risk of the Adriatic Spined Loaches (Genus Cobitis; Cypriniformes, Actinopterygii.

Directory of Open Access Journals (Sweden)

Ivana Buj

Full Text Available The region of Balkans is often considered as an ichthyologic "hot spot", with a great number of species and high portion of endemics living in fresh waters in a relatively small area. The Adriatic watershed in Croatia and Herzegovina is inhabited by six spined loach species (genus Cobitis whose extinction risk estimations were based solely on their extent of occurrence (and/or area of occupancy and its fragmentation, and conservation proposals do not consider diversity below species level. In this investigation we employed molecular genetic methods to describe present genetic structure of the Adriatic spined loaches and reveal their demographic history. The divergence of the Adriatic lineages inside the genus Cobitis started in Miocene and lasted until Pleistocene epoch. Geological events responsible for shaping recent diversity of spined loaches in the Adriatic basin are: the Dinarid Mountains upwelling, the evolution of Dinaric Lake system, local tectonic activity, river connections during glaciations and differences in sea level. Even though all the investigated species inhabit karstic rivers located in the same geographic area and that were subject of similar geological events, the results obtained reveal great differences in their genetic diversity and structure and point out the necessity of different conservation measures to ensure their future viability. High level of genetic polymorphism is characteristic for species located more to the south. Two species comprised of more than one population have completely different intraspecific structure; populations of C. illyrica are genetically distinct and represent separate evolutionary significant units, whereas intraspecific structure of C. narentana corresponds to metapopulational pattern. Without population genetic data, evolutionary significant units could be easily misidentified. Furthermore, the obtained results affirm that population genetic measurements are able to detect differences

The changing Mediterranean Sea — a sensitive ecosystem?

Science.gov (United States)

Turley, Carol M.

1999-08-01

I was asked to present a keynote paper on the socio-economic aspects of oceanographic research in the Mediterranean Sea in the Session on From Oceanographic Science to Policy at the International Conference on Progress in Oceanography of the Mediterranean Sea, Rome November 1997. The session was unique in that it included papers from oceanographers, social scientists and economists. For this reason I have aimed this paper towards, what I consider to be, social and economic issues that may have important oceanographic outcomes and vice versa. I have attempted to express them in a manner that can be understood by economists, social scientists, policy makers and oceanographers alike. The Mediterranean is highly populated and the greatest tourist destination in the world, both of which are predicted by UNEP to rise substantially in the future. Its blue waters, however, include some of the most extreme oligotrophic waters in the world such that it is only capable of supplying 50% of its requirements for fish. The relatively clear, pigment poor surface waters of the Mediterranean have a general increasing oligotrophy eastward with substantially lower phytoplankton, benthic and fish production in the eastern basin. The Mediterranean Sea is highly sensitive to climatic changes; it has high evaporation rates, low land runoff from few rivers and seasonal rains resulting in a deficit in its hydrological balance. This has worsened with the damming of rivers such as the Nile. Nutrient depleted Atlantic water flows into the Mediterranean through the narrow Strait of Gibraltar and exits after circulating the basin with nearly 10% more salt content. This hydrological imbalance may have far-reaching consequences in the Atlantic, producing similar climate changes in Northern Europe, to that seen during the last glaciation, and may be linked to a hydrological deficit in the Mediterranean Sea resulting from a decline in the Nile outflow. The basin-wide circulation, hot-dry and

First occurrence of the Indo-Pacific polychaete species Glycinde bonhourei Gravier, 1904 in the Hellenic seas (Northern Evvoikos Gulf

Directory of Open Access Journals (Sweden)

N. SIMBOURA

2008-05-01

Full Text Available A specimen of Glycinde bonhourei Gravier, 1904, an Indo-Pacific species, was found at a station near the metalliferous waste disposal in the Northern Evvoikos Gulf (Aegean Sea, eastern Mediterranean. This is the second report of this species in the Mediterranean Sea after its first finding in the Levantine basin (Israel and Egypt. This paper provides new information on its distributional range in the Mediterranean Sea.

Postglacial sedimentary regime around northern Sylt, South-eastern North Sea, based on shallow seismic evidence

DEFF Research Database (Denmark)

Boldreel, Lars Ole; Kuijpers, Antoon; Madsen, Emil B

2010-01-01

, in the outer delta, a dune field suggesting westerly-directed sediment transport is identified. The two dune fields appear to be separated by minor indefinite bed forms. The northern part of the Lister Tief is characterised by the presence of a channel with a depth of 20-30 mbsf (meter below sea level) (30......-40 msec TWT (Two Way Traveltime)) and displaying erosion towards the north. At the western termination of the channel the sediment transport pathway appears to be divided into two directions; one towards the outer delta, and one towards the sediment depocenter SW of Rømø. The Lister Ley is characterized......During the past 5 years the coastal zone offshore the northern part of the island of Sylt, has been investigated by sparker seismics and high-resolution subbottom profiling. The North Sea sector of the area is characterized by northward-directed sediment bypass as a result of strong long...

Lipid-rich and protein-poor carbon allocation patterns of phytoplankton in the northern Chukchi Sea, 2011

Science.gov (United States)

Yun, Mi Sun; Joo, Hui Tae; Park, Jung Woo; Kang, Jae Joong; Kang, Sung-Ho; Lee, Sang H.

2018-04-01

The carbon allocations of phytoplankton into different photosynthetic end products (lipids, LMWM, polysaccharides, and proteins) were determined to understand physiological conditions of phytoplankton in the northern Chukchi Sea during the Korean Arctic expedition, 2011, using the 13C isotope tracer technique. The carbon allocation rates of lipids, LMWM, polysaccharides, and proteins were 0.00009-0.00062 h-1, 0.00001-0.00049 h-1, 0.00001-0.00025 h-1, and 0.00001-0.00062 h-1 within the euphotic depths from surface to 1% light depths during our cruise period, respectively. Significant relationships between protein production rates and chlorophyll a concentrations (large and total) were found in this study. Moreover, we found a significant negative relationship between lipid production rates and ammonium concentrations. These relationships match well with the previous results for environmental/physiological conditions for phytoplankton growth. Overall, phytoplankton allocated more photosynthetic carbon into lipids (42.5 ± 17.7%) whereas relatively lower to proteins (20.4 ± 15.5%) in this study. The lipid-rich and protein-poor allocation patterns in this study suggest that phytoplankton in the northern Chukchi Sea were in a stationary growth phase under nutrient deficient condition based on biological and environmental conditions observed during our study period. Based on comparison with the previous studies in the northern Bering Sea and southern Chukchi Sea, we found that the photosynthetic carbon allocation patterns depending on physiological status of phytoplankton under the different growth and/or nutrient conditions could be largely vary at different regions in the Arctic Ocean. More intensive research on the physiological status of phytoplankton is further required to determine how phytoplankton response to the changing environmental conditions and consequently how they impact on higher trophic levels in marine ecosystems in the Arctic Ocean.

Prevalence of Corynosoma caspicum infection in Gasterosteus aculeatus fish in Caspian Sea, Northern Iran

Directory of Open Access Journals (Sweden)

Bahman Rahimi-Esboei

2017-09-01

Full Text Available Aim: There is little information about the prevalence of Corynosoma caspicum in fish particularly Gasterosteus aculeatus in Iran and the world. The aim of the present study was to find out the prevalence of acanthocephalan infection in Babolsar district, southern coastal of Caspian Sea, Northern Iran. Materials and Methods: Between September 2012 and August 2014, a total of 360 G. aculeatus fishes were randomly collected by drift nets from coastal regions in Babolsar and then examined the intestine and body cavity for worm infections. Results: A total of 360 G. aculeatus fishes, 109 (30.3% were found infected with at least one Corynosoma capsicum, and there was no significant association between genders and the prevalence infection of acanthocephalan. Moreover, there was a significant difference in infected rate between summer (79%, 86/109 and spring (21%, 23/109 (p<0.05. Conclusion: The high occurrence of Corynosoma infection in G. aculeatus indicates the enzootic constancy status of the infection in the southern coastal of Caspian Sea, Northern Iran.

Effects of Cross-axis Wind Jet Events on the Northern Red Sea Circulation

Science.gov (United States)

Menezes, V. V.; Bower, A. S.; Farrar, J. T.

2016-12-01

Despite its small size, the Red Sea has a complex circulation. There are boundary currents in both sides of the basin, a meridional overturning circulation, water mass formation in the northern part and an intense eddy activity. This complex pattern is driven by strong air-sea interactions. The Red Sea has one of the largest evaporation rates of the global oceans (2m/yr), an intricate and seasonally varying wind pattern. The winds blowing over the Northern Rea Sea (NRS, north of 20N) are predominantly southeastward along the main axis all year round; in the southern, they reverse seasonally due to the monsoonal regime. Although the winds are mostly along-axis in the NRS, several works have shown that sometimes during the boreal winter, the winds blow in a cross-axis direction. The westward winds from Saudi Arabia bring relatively cold dry air and dust from the desert, enhancing heat loss and evaporation off the Red Sea. These wind-jet events may contribute to increased eddy activity and are a trigger for water mass formation. Despite that, our knowledge about the cross-axis winds and their effect on NRS circulation is still incipient. In the present work we analyze 10-years of Quikscat scatterometer winds and altimetric sea surface height anomalies, together with 2-yrs of mooring data, to characterize the westward wind jet events and their impacts on the circulation. We show that the cross-axis winds are, indeed, an important component of the wind regime, explaining 11% of wind variability of the NRS (well-described by a 2nd EOF mode). The westward events occur predominantly in the winter, preferentially in January (about 15 events in 10-years) and have a mean duration of 4-5 days, with a maximum of 12 days (north of 22N). There are around 6 events per year, but in 2002-2003 and 2007-2008, twice more events were detected. The westward wind events are found to strongly modify the wind stress curl, causing a distinct positive/negative curl pattern along the main axis

Study of southern CHAONAN sag lower continental slope basin deposition character in Northern South China Sea

Science.gov (United States)

Tang, Y.

2009-12-01

Northern South China Sea Margin locates in Eurasian plate,Indian-Australia plate,Pacific Plates.The South China Sea had underwent a complicated tectonic evolution in Cenozoic.During rifting,the continental shelf and slope forms a series of Cenozoic sedimentary basins,including Qiongdongnan basin,Pearl River Mouth basin,Taixinan basin.These basins fill in thick Cenozoic fluviolacustrine facies,transitional facies,marine facies,abyssal facies sediment,recording the evolution history of South China Sea Margin rifting and ocean basin extending.The studies of tectonics and deposition of depression in the Southern Chaonan Sag of lower continental slope in the Norther South China Sea were dealt with,based on the sequence stratigraphy and depositional facies interpretation of seismic profiles acquired by cruises of“China and Germany Joint Study on Marine Geosciences in the South China Sea”and“The formation,evolution and key issues of important resources in China marginal sea",and combining with ODP 1148 cole and LW33-1-1 well.The free-air gravity anomaly of the break up of the continental and ocean appears comparatively low negative anomaly traps which extended in EW,it is the reflection of passive margin gravitational effect.Bouguer gravity anomaly is comparatively low which is gradient zone extended NE-SW.Magnetic anomaly lies in Magnetic Quiet Zone at the Northern Continental Margin of the South China Sea.The Cenozoic sediments of lower continental slope in Southern Chaonan Sag can be divided into five stratum interface:SB5.5,SB10.5,SB16.5,SB23.8 and Hg,their ages are of Pliocene-Quaternary,late Miocene,middle Miocene,early Miocene,paleogene.The tectonic evolution of low continental slope depressions can be divided into rifting,rifting-depression transitional and depression stages,while their depositional environments change from river to shallow marine and abyssa1,which results in different topography in different stages.The topographic evolvement in the study

The gill microbiota of invasive and indigenous Spondylus oysters from the Mediterranean Sea and northern Red Sea.

Science.gov (United States)

Roterman, Yahala Rina; Benayahu, Yehuda; Reshef, Lea; Gophna, Uri

2015-12-01

The gill tissue of bivalve mollusks hosts rich symbiotic microbial communities that may contribute to the animal's metabolism. Spondylus spinosus is an invasive oyster that has become highly abundant along the eastern Mediterranean Sea (EMS) coastline, but is scarce in the northern Red Sea (NRS), its indigenous region. The composition and seasonal dynamics of the gill microbial communities of S. spinosus were examined in both regions, using 16S rRNA gene amplicon sequencing. Additionally, two Red Sea Spondylus species, S. avramsingeri and S. pickeringae, were investigated using the same approach. Significant differences were found between microbial communities of the EMS S. spinosus and the three NRS species. Bacteria from the family Hahellaceae dominated the communities of the EMS S. spinosus and the NRS S. avramsingeri, oysters that are dominant in their habitat, yet were rare in the NRS S. spinosus and S. pickeringae, which are only seldom encountered. Bacterial communities of EMS S. spinosus were more similar to those of NRS S. spinosus than to those of other NRS Spondylus species, indicating that either part of the microbiota had co-invaded with their host into the Mediterranean Sea, or that there are species-specific selective constraints on microbial composition. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.

Delineation of marine ecosystem zones in the northern Arabian Sea during winter

Directory of Open Access Journals (Sweden)

S. Shalin

2018-03-01

Full Text Available The spatial and temporal variability of marine autotrophic abundance, expressed as chlorophyll concentration, is monitored from space and used to delineate the surface signature of marine ecosystem zones with distinct optical characteristics. An objective zoning method is presented and applied to satellite-derived Chlorophyll a (Chl a data from the northern Arabian Sea (50–75° E and 15–30° N during the winter months (November–March. Principal component analysis (PCA and cluster analysis (CA were used to statistically delineate the Chl a into zones with similar surface distribution patterns and temporal variability. The PCA identifies principal components of variability and the CA splits these into zones based on similar characteristics. Based on the temporal variability of the Chl a pattern within the study area, the statistical clustering revealed six distinct ecological zones. The obtained zones are related to the Longhurst provinces to evaluate how these compared to established ecological provinces. The Chl a variability within each zone was then compared with the variability of oceanic and atmospheric properties viz. mixed-layer depth (MLD, wind speed, sea-surface temperature (SST, photosynthetically active radiation (PAR, nitrate and dust optical thickness (DOT as an indication of atmospheric input of iron to the ocean. The analysis showed that in all zones, peak values of Chl a coincided with low SST and deep MLD. The rate of decrease in SST and the deepening of MLD are observed to trigger the algae bloom events in the first four zones. Lagged cross-correlation analysis shows that peak Chl a follows peak MLD and SST minima. The MLD time lag is shorter than the SST lag by 8 days, indicating that the cool surface conditions might have enhanced mixing, leading to increased primary production in the study area. An analysis of monthly climatological nitrate values showed increased concentrations associated with the deepening

Biogeochemical Impact of Long-Range Transported Dust over Northern South China Sea

Science.gov (United States)

Tsay, Si-Chee; Wang, S. H.; Hsu, N. C.

2011-01-01

Transpacific transport and impact of Asian dust aerosols have been well documented (e.g., results from ACE-Asia and regional follow-on campaigns), but little is known about dust invasion to the South China Sea (SCS). On 19-21 March 2010, a fierce Asian dust storm affected large areas from the Gobi deserts to the West Pacific, including Taiwan and Hong Kong. As a pilot study of the 7-SEAS (Seven South East Asian Studies) in the northern SCS, detailed characteristics of long-range transported dust aerosols were first observed by a comprehensive set of ground-based instruments deployed at the Dongsha islands (20deg42'52" N, 116deg43'51" E). Aerosol measurements such as particle mass concentrations, size distribution, optical properties, hygroscopicity, and vertical profiles help illustrate the evolution of this dust outbreak. Our results indicate that these dust particles were mixed with anthropogenic and marine aerosols, and transported near the surface. Satellite assessment of biogeochemical impact of dust deposition into open oceans is hindered by our current inability in retrieving areal dust properties and ocean colors over an extensive period of time, particularly under the influence of cloudy conditions. In this paper, we analyze the changes of retrieved Chlorophyll-a (Chl-a) concentration over the northern SCS, considered as oligotophic waters in the spring, from long-term SeaWiFS measurements since 1997. Over the past decade, six long-range transported dust events are identified based on spatiotemporal evolutions of PM10 measurements from regional monitoring stations, with the aid of trajectory analysis. Multi-year composites of Chl-a imagery for dust event and non-dust background during March-April are applied to overcome insufficient retrievals of Chl-a due to cloudy environment. Due to anthropogenic modification within a shallow boundary layer off the densely populated and industrial southeast coast of China, the iron ion activation of deliquescent dust

Delineation of marine ecosystem zones in the northern Arabian Sea during winter

Science.gov (United States)

Shalin, Saleem; Samuelsen, Annette; Korosov, Anton; Menon, Nandini; Backeberg, Björn C.; Pettersson, Lasse H.

2018-03-01

The spatial and temporal variability of marine autotrophic abundance, expressed as chlorophyll concentration, is monitored from space and used to delineate the surface signature of marine ecosystem zones with distinct optical characteristics. An objective zoning method is presented and applied to satellite-derived Chlorophyll a (Chl a) data from the northern Arabian Sea (50-75° E and 15-30° N) during the winter months (November-March). Principal component analysis (PCA) and cluster analysis (CA) were used to statistically delineate the Chl a into zones with similar surface distribution patterns and temporal variability. The PCA identifies principal components of variability and the CA splits these into zones based on similar characteristics. Based on the temporal variability of the Chl a pattern within the study area, the statistical clustering revealed six distinct ecological zones. The obtained zones are related to the Longhurst provinces to evaluate how these compared to established ecological provinces. The Chl a variability within each zone was then compared with the variability of oceanic and atmospheric properties viz. mixed-layer depth (MLD), wind speed, sea-surface temperature (SST), photosynthetically active radiation (PAR), nitrate and dust optical thickness (DOT) as an indication of atmospheric input of iron to the ocean. The analysis showed that in all zones, peak values of Chl a coincided with low SST and deep MLD. The rate of decrease in SST and the deepening of MLD are observed to trigger the algae bloom events in the first four zones. Lagged cross-correlation analysis shows that peak Chl a follows peak MLD and SST minima. The MLD time lag is shorter than the SST lag by 8 days, indicating that the cool surface conditions might have enhanced mixing, leading to increased primary production in the study area. An analysis of monthly climatological nitrate values showed increased concentrations associated with the deepening of the mixed layer. The

Economic Possibilities of Shipping though Northern Sea Route1

Directory of Open Access Journals (Sweden)

Sung-Woo Lee

2014-12-01

Full Text Available Global warming and climate change haves brought a new issue in the Arctic sea. Therefore, we can now explore new shipping routes through the Arctic Ocean instead of the existing commercial route. In particular, the Northern Sea Route (NSR is one of the feasible shipping routes and, has provided tremendous shipping benefits. If the NSR becomes commercialized, we will be able to save about 5,000 nautical miles in distance and sailing time. In this study, we will emphasize some of the important results on the possibility of commercializing the shipping route in the Arctic. The NSR may bring positive economic effects in terms of shipping distance and time. For example, when utilizing the NSR, the maximum cargo traffic between Asia and Europe is expected to be around 46 million TEU. However, we also need to consider an expensive passage fee that is currently imposed by Russia. In conclusion, we maintain our efforts to protect the environment in the Arctic, in terms of logistics, and we need to explore every possible avenue to bring possible economic benefits to the North Pacific countries.

Experimental development of a new protocol for extraction and characterization of microplastics in fish tissues: First observations in commercial species from Adriatic Sea.

Science.gov (United States)

Avio, Carlo Giacomo; Gorbi, Stefania; Regoli, Francesco

2015-10-01

The presence of microplastics in the marine environment has raised scientific interest during the last decade. Several organisms can ingest microplastics with potentially adverse effects on the digestive tract, respiratory system and locomotory appendages. However, a clear evidence of tissue accumulation and transfer of such microparticles in wild organisms is still lacking, partially hampered by technical difficulties in isolation and characterization protocols from biological samples. In this work, we compared the efficacy of some existing approaches and we optimized a new protocol allowing an extraction yield of microplastics from fish tissues ranging between 78% and 98%, depending on the polymer size. FT-IR analyses confirmed that the extraction procedure did not affect the particles characteristics. The method was further validated on the fish mullet, Mugil cephalus, exposed under laboratory conditions to polystyrene and polyethylene; the particles were isolated and quantified in stomach and liver, and their presence in the hepatic tissue was confirmed also by histological analyses. A preliminary characterization revealed the presence and distribution of microplastics in various fish species collected along the Adriatic Sea. FT-IR analyses indicated polyethylene as the predominant polymer (65%) in the stomach of fish. The overall results confirmed the newly developed method as a reliable approach to detect and quantify microplastics in the marine biota. Copyright © 2015 Elsevier Ltd. All rights reserved.

Environmental impact of sea bass cage farming in the north Adriatic Sea

Directory of Open Access Journals (Sweden)

Domenico Lanari

2010-01-01

Full Text Available The main objective of the research was to reduce the organic and nutrient load under the net pen fish farms. An exper- iment was conducted to study the effects of artificial barriers fixed under a set of sea cages in order to reduce the envi- ronmental impact. The artificial barriers were made of four submerged galvanized steel pipes coated with plastic and placed on the sea floor (10 m depth in the Trieste gulf. The experimental design was as follows: control (C, cages with barriers (B, cages without barriers (WB. Measurements were taken on the surface as well as at 4 and 8m of depth. The trial lasted from the end of June 2000 to December 2001. Water quality parameters were not significantly influenced by the fish cages. Surface samples were characterised by lower levels of salinity and higher levels of oxygen and nitrate compared to those taken at 4 and 8 m. The artificial barriers favoured the establishment of a rich epiphytic fauna that took advantage of the presence of organic matter derived from fish cages. The two species Nucula nucleusand Neanthes caudataand the total bacterial counts were identified as potential indicators of pollution under the fish cage farms.

Zooxanthellate zoantharians (Anthozoa: Hexacorallia: Zoantharia: Brachycnemina) in the northern Red Sea

KAUST Repository

Reimer, James Davis; Montenegro, Javier; Santos, Maria E. A.; Low, Martyn E. Y.; Herrera Sarrias, Marcela; Gatins, Remy; Roberts, May B.; Berumen, Michael L.

2017-01-01

The Red Sea was one of the first areas of the Indo-Pacific to be investigated by marine taxonomists, and the literature on suborder Brachycnemina (Anthozoa: Hexacorallia: Zoantharia) for this region dates from the early nineteenth century. However, in the last 100 years there has been only one focused study on this group in the Red Sea. In the present study, specimens collected from the Saudi Arabian coast of the northern half of the Red Sea were phylogenetically analyzed by sequencing nuclear internal transcribed spacer regions of ribosomal DNA (ITS-rDNA), mitochondrial cytochrome oxidase subunit I (COI), and 16S ribosomal DNA (16S–rDNA). The new results were compared with historical data in the literature and recent results from the Persian Gulf and the southeastern coast of Africa. Results show the presence of six to seven potential Brachycnemina species in the Red Sea; five to six Palythoa species (Palythoa mutuki, P. tuberculosa, P. cf. heliodiscus, P. aff. heliodiscus, and one to two species within the P. sp. “sakurajimensis” group) together with Zoanthus sansibaricus. While P. mutuki, P. tuberculosa, and Z. sansibaricus are known to be widely distributed in the Indo-Pacific, P. cf. heliodiscus and P. sp. “sakurajimensis” have not been reported from the Persian Gulf or the southeastern coast of Africa, and the current results represent large range extensions for these two species. Only one of the observed species, P. aff. heliodiscus, is potentially endemic to the Red Sea, further demonstrating the generally wide distributions of most zooxanthellate Brachycnemina species.

Zooxanthellate zoantharians (Anthozoa: Hexacorallia: Zoantharia: Brachycnemina) in the northern Red Sea

KAUST Repository

Reimer, James Davis

2017-05-12

The Red Sea was one of the first areas of the Indo-Pacific to be investigated by marine taxonomists, and the literature on suborder Brachycnemina (Anthozoa: Hexacorallia: Zoantharia) for this region dates from the early nineteenth century. However, in the last 100 years there has been only one focused study on this group in the Red Sea. In the present study, specimens collected from the Saudi Arabian coast of the northern half of the Red Sea were phylogenetically analyzed by sequencing nuclear internal transcribed spacer regions of ribosomal DNA (ITS-rDNA), mitochondrial cytochrome oxidase subunit I (COI), and 16S ribosomal DNA (16S–rDNA). The new results were compared with historical data in the literature and recent results from the Persian Gulf and the southeastern coast of Africa. Results show the presence of six to seven potential Brachycnemina species in the Red Sea; five to six Palythoa species (Palythoa mutuki, P. tuberculosa, P. cf. heliodiscus, P. aff. heliodiscus, and one to two species within the P. sp. “sakurajimensis” group) together with Zoanthus sansibaricus. While P. mutuki, P. tuberculosa, and Z. sansibaricus are known to be widely distributed in the Indo-Pacific, P. cf. heliodiscus and P. sp. “sakurajimensis” have not been reported from the Persian Gulf or the southeastern coast of Africa, and the current results represent large range extensions for these two species. Only one of the observed species, P. aff. heliodiscus, is potentially endemic to the Red Sea, further demonstrating the generally wide distributions of most zooxanthellate Brachycnemina species.

Linkages between sea-ice coverage, pelagic-benthic coupling, and the distribution of spectacled eiders: observations in March 2008, 2009 and 2010, northern Bering Sea

Science.gov (United States)

Cooper, L.W.; Sexson, M.G.; Grebmeier, J.M.; Gradinger, R.; Mordy, C.W.; Lovvorn, J.R.

2013-01-01

Icebreaker-based sampling in the northern Bering Sea south of St. Lawrence Island in March of 2008, 2009, and 2010 has provided new data on overall ecosystem function early in the annual productive cycle. While water-column chlorophyll concentrations (−2 integrated over the whole water column) are two orders of magnitude lower than observed during the spring bloom in May, sea-ice algal inventories of chlorophyll are high (up to 1 g m−3 in the bottom 2-cm of sea-ice). Vertical fluxes of chlorophyll as measured in sediment traps were between 0.3 to 3.7 mg m−2 d−1 and were consistent with the recent deposition (days to weeks time scale) of chlorophyll to the surface sediments (0–25 mg m−2 present at 0–1 cm). Sediment oxygen respiration rates were lower than previous measurements that followed the spring bloom, but were highest in areas of known high benthic biomass. Early spring release of sedimentary ammonium occurs, particularly southeast of St. Lawrence Island, leading to bottom-water ammonium concentrations of >5 µM. These data, together with other physical, biological, and nutrient data are presented here in conjunction with observed sea-ice dynamics and the distribution of an apex predator, the Spectacled Eider (Somateria fischeri). Sea-ice dynamics in addition to benthic food availability, as determined by sedimentation processes, play a role in the distribution of spectacled eiders, which cannot always access the greatest biomass of their preferred bivalve prey. Overall, the data and observations indicate that the northern Bering Sea is biologically active in late winter, but with strong atmospheric and hydrographic controls. These controls pre-determine nutrient and chlorophyll distributions, water-column mixing, as well as pelagic-benthic coupling.

Records of Chrysomya albiceps in Northern Italy: an ecological and forensic perspective

Directory of Open Access Journals (Sweden)

S Vanin

2009-07-01

Full Text Available Knowledge of the carrion-breeding insects present at a local level is important and necessary for defining the post-mortem interval. Climate changes and globalisation are affecting species ranges and population dynamics. In this note, we report the incidence of Chrysomya albiceps (Diptera: Calliphoridae on dead human bodies and carrion in Northern Italy. These data confirm the spread of this species in the Northern regions. The partial sequencing of a 583-bp region of the cytochrome oxidase subunit 1 gene of an Adriatic population did not reveal any difference compared to the same genomic region in the African and South American populations of this species.

Analysis of polar organic contaminants in surface water of the northern Adriatic Sea by solid-phase extraction followed by ultrahigh-pressure liquid chromatography-QTRAP® MS using a hybrid triple-quadrupole linear ion trap instrument.

Science.gov (United States)

Loos, Robert; Tavazzi, Simona; Paracchini, Bruno; Canuti, Elisabetta; Weissteiner, Christof

2013-07-01

Water-soluble polar organic contaminants are discharged by rivers, cities, and ships into the oceans. Little is known on the fate, pollution effects, and thresholds of toxic chemical mixtures in the marine environment. A new trace analytical method was developed for the multi-compound analysis of polar organic chemical contaminants in marine waters. The method is based on automated solid-phase extraction (SPE) of one-liter water samples followed by ultrahigh-pressure liquid chromatography triple-quadrupole linear ion-trap mass spectrometry (UHPLC-QTRAP(®) MS). Marine water samples from the open Adriatic Sea taken 16 km offshore from Venice (Italy) were analyzed. Method limits of quantification (LOQs) in the low picogram per liter (pg/l) concentration range were achieved. Among the 67 target chemicals analyzed, 45 substances could be detected above the LOQ. The chemicals detected at the highest concentrations were caffeine (up to 367 ng/l), nitrophenol (36 ng/l), 2,4-dinitrophenol (34 ng/l), 5-methyl-1H-benzotriazole (18.5 ng/l), sucralose (11 ng/l), 1H-benzotriazole (9.2 ng/l), terbuthylazine (9 ng/l), alachlor (7.7 ng/l), atrazine-desisopropyl (6.6 ng/l), diethyltoluamide (DEET) (5.0 ng/l), terbuthylazine-desethyl (4.3 ng/l), metolachlor (2.8 ng/l), perfluorooctanoic acid (PFOA) (2.5 ng/l), perfluoropentanoic acid (PFPeA) (2.3 ng/l), linuron (2.3 ng/l), perfluorohexanoic acid (PFHxA) (2.2 ng/l), diuron (2.0 ng/l), perfluorohexane sulfonate (PFHxS) (1.6 ng/l), simazine (1.6 ng/l), atrazine (1.5 ng/l), and perfluorooctane sulfonate (PFOS) (1.3 ng/l). Higher concentrations were detected during summer due to increased levels of tourist activity during this period.

Small scale features of sound velocity structure in the northern Arabian sea during February - May 1974

Digital Repository Service at National Institute of Oceanography (India)

Somayajulu, Y.K.; Rao, L.V.G.; Varadachari, V.V.R.

at intermediate depths (200-400 m), influence the sound velocity structure and cause formation of an upper sound channel in the northern Arabian Sea. The Persian Gulf waters spread as tongues at 1 or 2 more levels (up to a limited extent), besides the prominent...

Extensional Structures on the Po Valley Side of the Northern Apennines

Science.gov (United States)

Bettelli, G.; Vannucchi, P.; Capitani, M.

2001-12-01

The present-day tectonics of the Northern Apennines is characterized by extension in the inner Tyrrhenian side and compression in the outer Po Valley-Adriatic side. The boundary separating the two domains, extensional and compressional, is still largely undetermined and mainly based on geophysical data (focal mechanisms of earthquakes). Map-scale extensional structures have been studied only along the Tyrrhenian side of the Northern Apennines (Tuscany), while along the Po Valley-Adriatic area the field studies concentrated on compressional features. A new, detailed field mapping of the Po Valley side of the Northern Apennines carried out in the last ten years within the Emilia Romagna Geological Mapping Program has shown the presence of a large extensional fault crossing the high Bologna-Modena-Reggio Emilia provinces, from the Sillaro to the Val Secchia valleys. This Sillaro-Val Secchia Normal Fault (SVSNF) is NW-SE trending, NE dipping and about 80 km long. The age, based on the younger displaced deposits, is post-Miocene. The SVSNF is a primary regional structure separating the Tuscan foredeep units from the Ligurian Units in the south-east sector of the Northern Apennines, and it is responsible for the exhumation of the Tuscan foredeep units along the Apennine water divide. The sub-vertical, SW-NE trending faults, formerly interpreted as strike slip, are transfer faults associated to the extensional structure. A geological cross-section across the SVSNF testifies a former thickness reduction and lamination of the Ligurian Units, as documented in the field, in the innermost areas of the Bologna-Modena-Reggio Emilia hills, implying the occurrence of a former extensional fault. These data indicate that the NE side of the water divide has already gone under extension reducing the compressional domain to the Po Valley foothills and plain. They can also help in interpreting the complex Apennines kinematics.

Ripensare le “Piattaforme Logistiche”: il Caso del Gateway dell’Alto Adriatico Rethinking “Logistics Platforms”: the case of the North Adriatic Gateway

Directory of Open Access Journals (Sweden)

Marco Dean

2011-11-01

the wider network of European corridors.

Until this moment, the logistics and strategic national plans have not been selective concerning the identification, along the TEN-T Corridors, of a few ports and freight villages which are able to become effective European gateways within the Italian territory and attract private investments. Moreover, these planning instruments, instead of basing their strategies on the most concrete corridors have preferred to conceive their policies on entirely “imaginary” ones. This is, for instance, the case of the Logistics Platform in the Nord-East area of Italy. This Platform has been organized around the uncertain Corridor V, rather than the more concrete (but not yet recognized in the European maps Adriatic-Baltic corridor. As a consequence, in this Region, several existing national infrastructures appear, at the moment, largely underused: 

1. a freight village of considerable size and European standards such as the Interporto Alpe Adria in Cervignano del Friuli, and
2. an international double railway such as the “Pontebbana” that links the North-East area of Italy with Austria, through the Alpine pass of Tarvisio, and which is already the southern segment of the Adriatic-Baltic corridor.

On the other hand, these infrastructures might play a significant role in light of the positive estimates about the new trends of maritime trades, which would realize a renewed centrality to the Mediterranean Sea (Drewry Shipping Consultants, 2010, and important development programs regarding the Adriatic ports, involving both public (Venice, Rijeka and private (Monfalcone-Triest, Koper stakeholders. The aim of these projects is to increase the competitive capacity of the North Adriatic port system and establish a more effective connection between it and the central and eastern parts of Europe, through the Baltic-Adriatic Corridor, so as to constitute the so-called North Adriatic Gateway