Folic acid in coastal waters of the Adriatic Sea

2002 ◽  
Vol 53 (8) ◽  
pp. 1245 ◽  
Author(s):  
Marta Plavšić ◽  
Senka Terzic ◽  
Marijan Ahel ◽  
C. M. G. van den Berg
Keyword(s):  
Folic Acid ◽  
Water Column ◽  
Adriatic Sea ◽  
Photosynthetic Pigment ◽  
Northern Adriatic Sea ◽  
Po River ◽  
Northern Adriatic ◽  
Vitamin B Group ◽  
Two Parameters ◽  
The Impact

The concentration of folic acid (FA), an important constituent of the vitamin B group, was determined over a period of 2 years in the water column of a small meromictic saline lake on the eastern Adriatic coast (Rogoznica Lake), as well as in the western part of the northern Adriatic Sea. The FA concentration was over the range of 0.1–13.5 nM in the oxic part of Rogoznica Lake, and 0.1–22 nM in the northern Adriatic, with a maximum of 22 nM in the upper layer of the water column, possibly caused by the impact of Po River freshets on the FA concentrations. A weak but statistically significant correlation was established between photosynthetic pigment zeaxanthin, a characteristic biomarker of cyanobacteria, and FA in the oxic layer of the Rogoznica Lake (r2 = 0.3967; n = 29; P < 0.01), indicating cyanobacteria as a possible source of FA in this ecosystem. A statistically significant correlation (r2 = 0.36; n = 18; P < 0.01) between the two parameters was also found for the surface layer of the northern Adriatic (0 m). However, a low contribution of cyanobacteria to the total photosynthetic biomass in the northern Adriatic, and a lack of correlation between FA and zeaxanthin in the deeper layers of the water column, suggested that cyanobacteria were probably not the main source of FA in these waters. A stronger relationship (r2�= 0.46; n = 16; P < 0.01) between FA and chlorophyll b was found for the top 10 m of the northern Adriatic, indicating green algae as one of the possible sources of FA.

Modeling the Environmental Dynamics of the Northern Adriatic Sea with an explicit benthic-pelagic coupling.

2021 ◽  
Author(s):  
Marco Zavatarelli ◽  
Isabella Scroccaro ◽  
Tomas Lovato
Keyword(s):  
General Circulation ◽  
Adriatic Sea ◽  
Circulation Model ◽  
Open Boundary ◽  
Biogeochemical Model ◽  
Northern Adriatic Sea ◽  
Po River ◽  
Northern Adriatic ◽  
Benthic Pelagic Coupling ◽  
The Impact

&lt;p&gt;In the framework of the European Project H2020 &quot;ODYSSEA&quot; (Operating a network of integrated observatory systems in the Mediterranean SEA,&amp;#160;http://odysseaplatform.eu/) a forecasting modeling system of the coupled physical and biogeochemical conditions&amp;#160;of the Northern Adriatic Sea is under development.&lt;/p&gt;&lt;p&gt;The modeling system consists of the on-line coupling of the European general circulation model - NEMO (Nucleus for European&amp;#160;Modeling of the Ocean,&amp;#160;https://www.nemo-ocean.eu/), with the marine biogeochemical model - BFM (Biogeochemical Flux Model,&amp;#160;bfm-community.eu/).&lt;br&gt;The biogeochemical component of the model includes the simulation of the biogeochemical processes of both water column and sediments and their coupling. The model is run for the first time in the Northern Adriatic Sea with an explicit benthic-pelagic coupling.&lt;/p&gt;&lt;p&gt;The horizontal spatial discretization is defined by a rectangular grid of 315 &amp;#215; 278 cells, having a horizontal resolution of about 800 m. The vertical resolution is defined at 2 m, with 48 z-levels regularly spaced. Currently the atmospheric forcing are the ECMWF 6hr analysis atmospheric fields. The river supplies of fresh water and nutrient salts consider the daily runoff of the Po river, while the other&amp;#160;rivers within the study area are included as climatological values. The open boundary conditions of the modeling system come from the Copernicus Marine Environment Monitoring Service (CMEMS,&amp;#160;http://marine.copernicus.eu/).&lt;/p&gt;&lt;p&gt;In this work, the hindcast simulations encompassing the period 2000 &amp;#8211; 2009 are validated against available observations from in situ and satellite platforms for sea surface temperature, chlorophyll-a and dissolved inorganic nutrients and, in order to evaluate the impact of a resolved benthic biogeochemical dynamics,&amp;#160; compared against simulations results obtained utilising a simple benthic closure parameterisation.&lt;/p&gt;

scholarly journals Numerical modelling of sediment transport in the Adriatic Sea

2014 ◽  
Vol 11 (3) ◽  
pp. 1391-1433 ◽  
Author(s):  
A. Guarnieri ◽  
A. J. Souza ◽  
N. Pinardi ◽  
P. Traykovski
Keyword(s):  
Sediment Transport ◽  
Adriatic Sea ◽  
Transport Model ◽  
Data Availability ◽  
Western Coast ◽  
Po River ◽  
Northern Adriatic ◽  
Coastal Belt ◽  
Italian Coasts ◽  
The Impact

Abstract. A new sediment transport model, considering currents, tides and waves is presented for the Adriatic Sea basin. The simulations concentrate on the winter of 2002–2003 because of field data availability and interesting intermittent processes occurrence. A process oriented analysis is performed to investigate the impact that Sirocco and Bora wind regimes have on sediment transport. The comparisons of the simulations with the observed data show that the model is capable to capture the main dynamics of sediment transport along the Italian coasts and the sediment concentration within the water column. This latter can reach values up to several g L−1, especially within the first centimetres above the bottom. The sediments are transported mainly southwards along the Italian coasts, consistently with the known literature results, except during Sirocco wind events, which can be responsible for reversing the coastal circulation in the northern area of the basin, and consequently the sediment transport. The resuspension of sediments is also related to the specific wave regimes induced by Bora and Sirocco, the former inducing resuspension events near the coasts while the latter causing a more diffused resuspension regime in the Northern Adriatic basin. Beside the realistic representation of short timescales resuspension/deposition events due to storms, the model was also used to investigate persistent erosion or deposition areas in the Adriatic Sea. Two main depocenters were identified: one, very pronounced, in the surroundings of the Po river delta, and another one a few kilometres off the coast in front of the Ancona promontory. A third region of accumulation, even if less intense, was found to be offshore the southernmost limit of the Gargano region. On the contrary the whole western coast within a distance of a few kilometres from the shore was found to be subject to prevailing erosion. The comparison with observed accumulation and erosion data shows that the model captures well the main depocenters in the domain and the erosion within the very coastal belt of the western side of the basin, but seems to be too erosive in a few areas, in particular those where the contribution of sediment inflow to the sea of some minor but intermittently important rivers is not considered in a realistic way as input to the model.

Reconstructing the baseline population structure of the exploited bivalve Arca noae in the Northern Adriatic Sea

2021 ◽  
Author(s):  
Saskia Macharia ◽  
Rafał Nawrot ◽  
Michaela Berensmeier ◽  
Ivo Gallmetzer ◽  
Alexandra Haselmair ◽  
...  
Keyword(s):  
Adriatic Sea ◽  
Size Structure ◽  
Anthropogenic Impacts ◽  
Natural State ◽  
Published Data ◽  
Northern Adriatic Sea ◽  
Important Species ◽  
Northern Adriatic ◽  
Shell Bed ◽  
The Impact

&lt;p&gt;The Northern Adriatic Sea is one of the most impacted ecosystems worldwide with a long history of anthropogenic impacts, ranging from overfishing and bottom trawling to eutrophication, deoxygenation and pollution. The impact of these multiple pressures on populations of economically important species is often difficult to evaluate due to paucity of long-term monitoring data. The edible bivalve Noah&amp;#8217;s Ark shell (&lt;em&gt;Arca noae &lt;/em&gt;L.) was intensively harvested in the eastern Adriatic Sea until 1949-1950 when it suffered a catastrophic population collapse due to unknown agents. The assessment of its subsequent recovery is hindered by the lack of data on the population size structure prior to that event. To reconstruct the natural baseline state of populations of &lt;em&gt;A. noae&lt;/em&gt; before the onset of extensive harvesting, we studied fossil assemblages from two 1.5-m-long sediment cores collected in the southern Gulf of Trieste (off Piran, Slovenia), both recording the last ~9,500 years.&lt;/p&gt;&lt;p&gt;The abundance and shell length of &lt;em&gt;A. noae&lt;/em&gt; remained low in the lower part of the cores but increased strongly within the oyster-&lt;em&gt;Arca&lt;/em&gt; shell bed corresponding to maximum flooding and early highstand sea-level phases (6,500-1,000 years ago). In contrasts, the top 8 cm of the core (the late highstand phase), marked by high concentration of pollutants and organic enrichment, contained only few and small (&lt; 10 mm) &lt;em&gt;A. noae&lt;/em&gt; shells. Moreover, no living individuals were found in grab samples taken from the two stations suggesting that the dense populations of &lt;em&gt;A. noae, &lt;/em&gt;&lt;span&gt;persisting &lt;/span&gt;&lt;span&gt;there&lt;/span&gt; &lt;span&gt;for&lt;/span&gt;&lt;span&gt; several thousand years, &lt;/span&gt;were locally extirpated in the 20&lt;sup&gt;th&lt;/sup&gt; century. To evaluate population recovery in other parts of the NE Adriatic, we compared the size distribution of&lt;em&gt; &lt;/em&gt;fossil&lt;em&gt; &lt;/em&gt;&lt;em&gt;A. noae&lt;/em&gt; from the shell bed interval to the previously published data on living populations of this species sampled&lt;em&gt; &lt;/em&gt;along Istrian peninsula between 1966 and 1978. Both fossil and extant populations were characterized by similar &lt;span&gt;median &lt;/span&gt;&lt;span&gt;size, &lt;/span&gt;&lt;span&gt;modal size &lt;/span&gt;&lt;span&gt;class and&lt;/span&gt;&lt;span&gt; proportion of &lt;/span&gt;&lt;span&gt;specimens &gt; 50 mm &lt;/span&gt;&lt;span&gt;(minimal legal landing size). &lt;/span&gt;&lt;span&gt;These results suggest that within few &lt;/span&gt;&lt;span&gt;decades&lt;/span&gt;&lt;span&gt; after the &lt;/span&gt;&lt;span&gt;1949-1950 &lt;/span&gt;&lt;span&gt;mass mortality event &lt;/span&gt;&lt;span&gt;the size structure of populations &lt;/span&gt;&lt;span&gt;of&lt;/span&gt; &lt;span&gt;&lt;em&gt;A. noae&lt;/em&gt;&lt;/span&gt; &lt;span&gt;have largely returned to their earlier, natural state.&lt;/span&gt;&lt;span&gt; The recovery was &lt;/span&gt;&lt;span&gt;spatially variable, however, as attested by&lt;/span&gt;&lt;span&gt; the decline of&lt;/span&gt; &lt;span&gt;&lt;em&gt;A. noae&lt;/em&gt;&lt;/span&gt; &lt;span&gt;populations &lt;/span&gt;&lt;span&gt;due to loss of &lt;/span&gt;&lt;span&gt;suitable shell-bed habitat&lt;/span&gt;&lt;span&gt;s&lt;/span&gt;&lt;span&gt; in&lt;/span&gt;&lt;span&gt; the two &lt;/span&gt;&lt;span&gt;studied&lt;/span&gt;&lt;span&gt; station&lt;/span&gt;&lt;span&gt;s&lt;/span&gt;&lt;span&gt; off Piran.&lt;/span&gt;&lt;/p&gt;

scholarly journals Seasonal and Interannual Trends of Oceanographic Parameters over 40 Years in the Northern Adriatic Sea in Relation to Nutrient Loadings Using the EMODnet Chemistry Data Portal

Water ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 2280 ◽  
Author(s):  
Federica Grilli ◽  
Stefano Accoroni ◽  
Francesco Acri ◽  
Fabrizio Bernardi Aubry ◽  
Caterina Bergami ◽  
...  
Keyword(s):  
Climate Changes ◽  
Management Practices ◽  
Adriatic Sea ◽  
Nutrient Concentrations ◽  
Data Series ◽  
Mean Flow ◽  
Northern Adriatic Sea ◽  
Po River ◽  
Northern Adriatic

Long-term data series (1971–2015) of physical and biogeochemical parameters were analyzed in order to assess trends and variability of oceanographic conditions in the northern Adriatic Sea (NAS), a mid-latitude shallow continental shelf strongly impacted by river discharges, human activities and climate changes. Interpolation maps and statistical models were applied to investigate seasonal and spatial variability, as well as decadal trends of temperature, salinity, chlorophyll-a and nutrients. This analysis shows that sea surface temperature increased by +0.36% year−1 over four decades. Annual mean flow of the Po River markedly changed due to the occurrence of periods of persistent drought, whereas the frequency of flow rates higher than 3000 m3 s−1 decreased between 2006 and 2015. Moreover, we observed a long-term decrease in surface phosphate concentrations in Po River water (−1.34% year−1) and in seawater (in summer −2.56% year−1) coupled, however, to a significant increase in nitrate concentration in seawater (+3.80% year−1) in almost all seasons. These changes indicate that the nutrient concentrations in the NAS have been largely modulated, in the last forty years, by the evolution of environmental management practices and of the runoff. This implies that further alteration of the marine environment must be expected as a consequence of the climate changes.

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

2008 ◽  
Vol 26 (4) ◽  
pp. 731-746 ◽  
Author(s):  
S. Cosoli ◽  
M. Gačić ◽  
A. Mazzoldi
Keyword(s):  
Water Column ◽  
Wind Stress ◽  
Time Scale ◽  
Adriatic Sea ◽  
Sea Breeze ◽  
Venice Lagoon ◽  
Northern Adriatic Sea ◽  
Northern Adriatic ◽  
Modes Of Variability ◽  
Tidal Signal

Abstract. 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 motion over the entire water column.

scholarly journals Spatial distribution of suspended solids during short-term high river discharge in the Bay of Koper, northern Adriatic Sea

2018 ◽  
Vol 19 (1) ◽  
pp. 36 ◽  
Author(s):  
ROK SOCZKA MANDAC ◽  
DUŠAN ŽAGAR
Keyword(s):  
Spatial Distribution ◽  
River Discharge ◽  
Suspended Solids ◽  
Adriatic Sea ◽  
Anthropogenic Influences ◽  
Short Term ◽  
Northern Adriatic Sea ◽  
Northern Adriatic ◽  
River Flooding ◽  
The Impact

The Bay of Koper (BoK) located in the Gulf of Trieste (northern Adriatic Sea) is subject to a variety of anthropogenic influences; pollutants from inland are transported to the sea by the local rivers. The impact of high river discharge on suspended solids distribution was assessed by analysing results of an extensive measurement campaign conducted during two episodes of river flooding. The spatial analysis demonstrated the area influenced by fresh water and the distribution of inorganic suspended solids (ISS). The results were then used to calibrate the PCFLOW3D model and to simulate two episodes. A correlation was identified between the measurements and short-term simulations found in the central part of the bay. The results confirm the methods and the model used in this study to be appropriate for studying complex suspended solids processes in coastal areas.

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