Coordinator: Dr. Nadia Pinardi


Detailed explanation of costs



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Detailed explanation of costs



  • 1997 1998

  • Consum. Travel Personnel Tot. Consum. Travel Personnel Tot.



  • 20 5 10 35 20 5 10 35





  • B.3.3. The Water Masses Variability in the Tyrrhenian Sea

  • Principal scientist: Dr.Vincenzo Artale ( ENEA-Casaccia, Roma)



  • Background



  • The principal water masses of the Tyrrhenian sea are the Modified Atlantic Water (MAW) and the Levantine Intermediate Water(LIW). The MAW and the LIW flow into Tyrrhenian sea through them Sardinia-Sicily section along the Sicilian coast. Successively, a part of these waters flow northwards. The remaining recirculates and exits through the same section more towards the west. The information coming from Tyrrhenian budget computations indicate that the resulting water balance requires a remarkable amount of mixing between LIW and both the surface and deep waters (DW). Thus the Tyrrhenian Sea appears to store and modify significant amounts of both the LIW, entering into it from the eastern Mediterranean, and the Western Mediterranean Atlantic and Deep Waters. A more accurate evaluation of the basin inflow/outflow and of the interior processes is necessary for a thorough understanding the seasonal and interannual variability of the Tyrrhenian Sea making this basin one of the more important to understand the modified characteristic of the LIW in the western Mediterranean basin.

  • The surface circulation is the most known and is largely influenced by the wind effect and the mean flow, while the intermediate circulation is only approximately known. One of the most interesting experimental results of the La Spezia group are relative to the straits, which indicate as the LIW moves along very narrow stream, largely influenced by the bottom, which are very difficult to follow along the basin.

  • In order to start a more intense interaction between numerical modeling and hydrographic survey we propose to study the Tyrrhenian circulation using the three-dimensional primitive equation model using a new data set. This new data set will be made by the merging of the new measurements performed in the last years by CNR laboratory of La Spezia with climatological data. Therefore the numerical models we plan to use is at high horizontal and vertical resolution (1/12 degree and 50 levels) because we need to resolve very well either of them to study the spreading of the LIW into the basin; finally we intend to force the model with the ECWMF wind stress.

  • Considering the closeness or our scientific interests to those of other scientists participating to the `Progetto Strategico' we are planning to develop all the different phases of the project at tight contact with them. We will integrate into the model the experimental evidence of water mass variability at the strait of Corsica and at the Sardinia Channel (SO-La Spezia) and the results of the recent studies of the wind effect on the Tyrrhenian circulation analyzed by means of a free-surface, barotropic primitive equation (Task B.3.1).







  • Scientific Objectives



  • -to implement an eddy resolving numerical model of the Tyrrhenian Sea using realistic boundary conditions and topography



  • -simulate the water mass transformation into the basin and comparison with the observations



  • Workplan



  • - Analysis of the latest oceanographic surveys for the definition of the open boundary conditions of models

  • - Implementation of the Tyrrhenian high resolution numerical model

  • - Sensitivity experiments to different forcings (wind stress, heat fluxes, etc.)











  • Description of team



  • Institution Personnel Position Man/month

  • ENEA, Casaccia,Roma . Vincenzo Artale Scientist 4

  • Wolfango Rupolo Scientist 3

  • Andrea Cappelletti Scientist 3

  • Paola Picco Scientist 3

  • Antonio Baldi Technician 3



    1. Financial budget *

    1. Total

    1. 1997

    1. 25

    1. 1998

    1. 25

    1. Total

    1. 50

  • *All costs are in Millions of Lire





  • Detailed explanation of costs



  • 1997 1998

  • Consum. Travel Personnel Tot. Consum. Travel Personnel Tot.



  • 20 5 25 20 5 25











  • B.3.4. Construction of a high resolution climatological data set for the Tyrrhenian Sea

  • Principal Scientist: Dr. Gian Pietro Gasparini (SO-CNR, La Spezia)



  • During the past years various hydrographic studies have yielded quasi-synoptic descriptions of the Tyrrhenian Basin. It is particularly notable at this regard, the IUN Atlas (Aliverti et al., 1968), while some papers (Krivosheya and Ovchinnikov, 1973; Krivosheya, 1983) provided a seasonal description of the geostrophic current fields.

  • Because of some new available surveys, the previous studies and data sets need to be updated. In spite of the existence of the MODB data set (Brasseur, 1995) and the Levitus Atlas 1994 data set, the specific processes present in the area (Hopkins, 1988) need a climatology with very fine resolution. A new data set taking in account the most recent results on the Tyrrhenian circulation (Pistek et al., 1995; Zodiatis and Gasparini, 1996) seems to be important.

  • Our motivation in producing a climatological data set specific for the Tyrrhenian Basin is based on the recognition that this basin is deeply involved in the Mediterranean circulation and plays a crucial role in modifying its hydrographic characteristics. Furthermore, the determination of the water mass properties and circulation of the Tyrrhenian basin seems to be important in the evaluation of the climatic variability of the Mediterranean. The new data set will be used by the modeling subtasks described above.



  • Scientific Objectives



  • - produce a highly resolved climatological data set for the Tyrrhenian, gridded at least at 1/8 degrees of resolution.

  • - merge the data set with the existing MODB data base







  • Workplan



  • -collect and harmonize the data

  • -analyze the data and make a gridded climatology



  • Description of team



  • Institute Personnel Position Time(%) Man/month

  • SO, CNR, La Spezia Gian Pietro Gasparini Scientist 20 3

  • Carlos Balestrini Scientist 30 4



    1. Financial budget *

    1. Total

    1. 1997

    1. 30

    1. 1998

    1. 30

    1. Total

    1. 60









  • TASK B.3.5 Studies of the general circulation variability via surface drifters simulations

  • Principal Scientist: Dr. F.Tampieri (IMGA-CNR, Bologna)



  • Background



  • The atmospherically forced interannual variability has been described in recent years by General Circulation Model (GCM) results (Pinardi et al., 1997, Korres et al., 1996). It is now recognized that atmospheric forcing variability at seasonal and interannual time scales can induce changes in the upper ocean structure of the currents. The major driving mechanism resides in the changes of the wind stress curl during the winter which can offset the regular occurrence of summer and winter seasons in the year following a strong winter anomaly in wind stress. The observational evidence for such changes is still scarce: only the Straits measurements described in Task B.1 and the few cruises done by POEM between 1985 and 1988 give an idea of the occurrence of dramatic changes in the upper ocean circulation of the basin.

  • The in situ data requirements for monitoring the changes at the basin level are very large and still far to come. However, in recent years, the Saclant Center in La Spezia has started a surface drifters program which considered tracking of drifters for few years continuously. This is a crucial data set to validate and check hypothesis on the mechanisms which control interannual variability in the Mediterranean Sea due to the large scale coverage which such data can offer. We propose then to implement a drifter simulation within the GCM set up during the past five years at IMGA. This GCM has been elaborated as a result of two Mast Projects funded from 1990 until 1996. It is implemented in the whole Mediterranean area, with daily atmospheric forcing at the air-sea interface and with sophisticated parametrizations of vertical mixing in the water column. For reference see Roussenov et al. (1995). We propose here to use such model and validate the response with comparison to the surface drifters data of Saclant.











  • Scientific Objectives



  • The subtask proposes to study the interannual variability of the Mediterranean Sea induced by atmospheric forcing through simulations with a GCM. The second aim is to diagnose particle trajectories and finally drifters to be able to compare with real data surface drifters such as the Saclant drifters data set for 1994-1995.





  • Workplan



  • -Produce a GCM simulation for the time period 1991-1995. In order to do so acquire 1995 ECMWF data.

  • -Implement lagrangian trajectory simulations for the same time period using different deployment positions. Add Lagrangian turbulence model as described for other world ocean situations (Griffa et al., 1996)

  • -Implement surface drifters simulations to reproduce the Saclant data set, based on stochastic processes (Thomson, 1987, Cesari and Tampieri, 1996).



  • Description of Team



  • Institution Personnel Position Man/month

  • IMGA-CNR (1) Tampieri Scientist 1

  • Cesari Ph.D. Student 12

  • SO, La Spezia (2) A.Griffa Scientist 1



    1. Financial budget *

    1. Total

    1. 1997

    1. 59

    1. 1998

    1. 59

    1. Total

    1. 118

  • *All costs are in Millions of Lire



  • Detailed explanation of costs



  • 1997 1998

  • Consum. Travel Personnel Tot. Consum. Travel Personnel Tot.



  • Unit 1 20 5 9* 34 20 5 9* 34



  • Unit 2 20 5 25 20 5 25

  • 59 59

  • * Partial funding of a Ph.D. student





















  • B.3.6 Prognostic and adjoint simulations of the Mediterranean Sea general circulation

  • Principal scientist: Dr. A.Bergamasco (ISDGM-CNR, Venezia)



  • Background



  • The meteorological forcing (wind and buoyancy) are the main causes of the oceanic circulation and its variability. Also the Mediterranean circulation is driven almost in equal proportion by wind stresses and heat fluxes. In order to understand the Mediterranean Sea general circulation and its interannual variability as a response to meteorological forcing variability, a set of prognostic and adjoin calculations will be carried out.





  • Scientific Objectives



  • The main focus will be the description and understanding of the evolution of the thermohaline cell responsible of the seasonal and interannual changes of the circulation. All the experiments will use in situ data both for assimilation and verification of the model results. In particular, the mechanisms of the preconditioning of the intermediate and deep water formation processes in the Eastern Mediterranean will be explored.





  • Workplan



  • To reach the scientific goals we will follow a twofold strategy:

  • 1. Use of prognostic models with high resolution in order to explore the mechanisms determining the water mass formation preconditioning phase, especially localized on the Rhode gyre winter intensification area. The GFDL (Geophysical Fluid Dynamics Laboratory, Princeton, US) and the Princeton Ocean Model (POM), already implemented in the Eastern Mediterranean area will be used. Experimental data from POEM will be used as initial fields and for model validation. Meteorological data from ECMWF will be used to force the Eastern Mediterranean general circulation model.

  • 2. Use the adjoint method applied to the GFDL model, to assimilate available experimental data (temperature and salinity data coming from POEM cruises) to find out the circulation of the Eastern Mediterranean for the last decade and connect with ad hoc experiments to understand the preconditioning mechanisms for Levantine Intermediate Water (LIW).



  • Description of Team



  • Institution Personnel Position Man/months



  • ISDGM-CNR Venezia A.Bergamasco Scientist 2

  • S.Carniel Scientist 3

  • E.Pitton Scientist 3

  • G.Arcari Scientist 3

  • METU-Erdemli, Turkey T.Oguz Scientist 1





    1. Financial budget *

    1. Total

    1. 1997

    1. 30

    1. 1998

    1. 30

    1. Total

    1. 60

  • *All costs are in Millions of Lire





  • B.3.7 Application of a model describing the two-way coupling between atmosphere and ocean to the analysis of the Mediterranean climate.

  • Responsible: P.Lionello (Dept. of Physics, Univ. of Padova)



  • Background



  • The whole model structure consists of three modules: The BOLAM (Bologna Limited Area Model) describing the atmospheric circulation, the POM (Princeton Ocean Model) describing the marine circulation, and the WAM (WAve Model) describing the air-sea interface and the dependence of the surface roughness on the wave spectrum. The model accounts for the interaction between atmosphere and ocean by including the feedbacks among the systems. The first version of the model which consists only of the BOLAM and WAM modules has been already applied to the study of the mid-latitudes cyclones and of the Mediterranean cyclogenesis. The addition of the POM module is in progress.



  • The wave model WAM is included because there are both theoretical and experimental evidences of an effect the ocean wave field on the momentum flux. In fact there are indications that the sea surface roughness is a decreasing function of a dimensionless parameter called wave age, implying that, for a fixed wind speed, a young windsea determines a larger momentum flux than an old one. No evidence is presently available for a similar effect on the heat and moisture fluxes remains presently controversial point because no evidence is available for supporting it.

  • This research aims to evaluate the effect of the wave field on the intraseasonal variations of the fluxes in the Mediterranean sea where the presence of complicated coastlines determines the prevalence of young windsea conditions during the storms. Moreover, the use of a coupled atmosphere-sea model, allows the computation of the heat and moisture fluxes using the actual values of the air temperature and humidity, and of the sea surface temperature, avoiding inconsistencies among the forcing of atmospheric and ocean model. Note that this model framework allows easily to account for high spatial and time resolution forcing of the ocean.



  • The proposal implies the use of the model for set of simulations, each with a duration of a few days, studying the behavior of the coupled systems during the passage of the atmospheric cyclones. The basic idea is to analyze selected cases and to obtain an evaluation of the effect of the coupling and of the high time and space resolution of the model on intraseasonal variability of atmosphere and sea in the Mediterranean region, by taking into account the frequency of the cyclones.





  • Scientific Objectives



  • A study of:

  • - the feedback between the atmosphere and the ocean on the intensity of the atmospheric cyclones in the Mediterranean Sea.

  • - the role of the feedback between atmosphere and ocean on the Mediterranean Climate

  • - the intermittence of the deep water formation and of the process during favorable meteorological conditions

  • - the role of the ocean wave field in the exchange of momentum, heat and moisture in the Mediterranean Sea, eventually correcting the estimate of the intraseasonal variations of the air-sea fluxes.



  • Workplan



  • - Complete the inclusion of the module POM in the complete model

  • - Simulate a series of selected cyclogenesis and passages of atmospheric cyclones

  • - Analyze the change of the sea stratification produced by the passage of the cyclone

  • - compare the high space and time resolution air-sea fluxes computed by the model with the climatic values and assess the potential benefits of the coupled simulations.



  • Description of Team



  • Institution\ Personnel Position Man/month

  • Univ of Padova P.Lionello Researcher 3

  • FISBAT P.Malguzzi Scientist 1

  • FISBAT A. Buzzi Scientist 1

  • ISDGM A.Bergamasco Scientist 1













    1. Financial budget *

    1. Total

    1. 1997

    1. 45

    1. 1998

    1. 20

    1. Total

    1. 65

  • *All costs are in Millions of Lire





  • TASK B.4 Water column and sediment structure in the deep Mediterranean basins: climate variability experiment

  • Responsible: Dr. Bruno Della Vedova (DINMA, Trieste)



  • In the past decade the Eastern Mediterranean has been the site of a climatic change in the deep ocean structure which could affect for many decades the thermohaline circulation of the Eastern Mediterranean. The deep water masses of the Eastern Mediterranean have been traditionally found to be formed of Adriatic deep waters, exiting the Otranto Strait and diffusing slowly in the whole central Mediterranean basin. In the late eighties-early nineties, however, a warmer and denser water mass than the deep Adriatic waters outflew from the Aegean Sea and renewed the deep central Mediterranean layers. This climatic event has been traced in the oceanographic records acquired within the international cooperative POEM (Physical Oceanography of the Eastern Mediterranean) research Program ( Roether et al., 1996; Malanotte-Rizzoli et al., 1996). The thermal transient associated to this warming event has been memorized in the sediment thermal history and was measured by the MEDRIFF (An Integrated Investigation of the Fluid-Flow Regime of the Mediterranean Ridge) Consortium (Della Vedova et al., 1996). The analysis of the MEDRIFF thermal data allowed to reconstruct the space and time variability of the warming event across a 300 km long transect from the Aegean strait, west of Crete, to the Ionian abyssal plain (Della Vedova et al., 1996). Measurements collected in the same area at different times indicated that the thermal structure in the bottom-water and sediments had been modified significantly on weekly, monthly, and interannual time-scales. Modeling of the conductive heat propagation into the sediment explains the observed thermal anomalies assuming up to 0.6°C warming of the bottom-waters that propagated southwestwards from the Hellenic Trench to the crest area of the Mediterranean Ridge. The sediment warming started in summer 1992 in the Matapan Trench and reached the Mediterranean Ridge crest in late 1992-early 1993, with an attenuated thermal pulse of +0.1°C in amplitude. The average spreading velocity of the sediment warming is about 0.7-0.9 km/day. A challenging question arises whether this change in the thermohaline circulation is resulting from a time constrained convergence of climatic factors or it is an early stage of a cyclic, longer time scale event, like those which left sapropels in the sediments as records of their occurence (Cita et al., 1991). We assume that , since its appearence, it is affecting biogeochemical cycling in this area and its effects can be assessed in the the trophic balance and in the benthic pelagic coupling.

  • The target of Task B4 is therefore to follow the evolution of this regional change and define its effects on biogeochemical parameters in the water column, at the water-sediment interface and in the deep sediments. This research is essentially based on measurements of fluxes of materials and energy between the three compartments (water column, surface sediment and deep sediment): downward fluxes of particles from the photic layer to the sea floor, fluxes of heat and dissolved species across the water-sediment interface, and into the deep sediment.

  • The experimental work will be carried out in a corridor along the thermohaline pathway of this newly formed deep water mass, where oceanographic conditions and sea floor morphology allow the signals to be recorded in the sediments.

  • A feasibility study for the deployment of a deep sea observatory is one of the expected outputs of this task. The station will be designed to provide a long-term climatic monitoring of the marine ecosystems, by continuous measurements of physical parameters. The site will be also selected on the basis of previous (POEM-BC Program) and ongoing oceanographic investigations (EU-MATER, SINAPSI: this Task and Task B5.1)

  • Task B4.1 concerns oceanographic measurements in the water column, heat flux measurements in the sediment and core sampling. The cores will be also analysed for biostratigraphic and geochemical palaeoenvironmental proxies. The Task B.4.2 concerns the assessment of biogeochemical fluxes based on data from the above mentioned field experimental station





  • Task B.4.1 Hydrodynamic structure, heat fluxes across the sediment-water interface and stratigraphic records of past climatic events (in close connection with Subproject D)

  • Principal scientist: Prof. Bruno Della Vedova (DINMA - TS)



  • Background



  • The sediment is a large archive of information of the events which affected the past history of the basin. The sedimentary sequence keeps record of the geological evolution of the basin and the surrounding margins, of the changing physical characteristics of the water masses and of the evolution of the marine ecosystems. In particular a detailed study on the anoxic sediments will be continued; they keep record of the fluxes of biogenic material from the water column to the sediments and thus also of the changes consequent to climatic events of this kind. The integration of geological, geophysical, chemical and biological studies would allow us to recognize evidences for climate changes and cyclic events. The thermal transients on the seafloor are temporary memorized in the sediment, this process provides us an important information on the time evolution of the sea bottom warming process.

  • .



  • Scientific Objectives



  • The general objective of our investigation will be to study and to recognize changes in the water column, sediment structure (physics, chemistry and biology) of the deep Mediterranean Basin, related to climate variability at different time scales. To achieve this, the following specific objectives of this subtask are proposed:



    • Define areas/basins of the Mediterranean Sea critical with respect to climate variability.

    • Assess heat, fluid and chemical fluxes through the seafloor and their interrelationships in key areas (in conjunction with Subtask B4.2, task B1.3 and tasks of sub-project C).

    • Establish time series of Holocene/Late Pleistocene paleoceanographic and climatic changes (e.g. source areas, paleoproductivity.) from anoxic laminated sediments.

    • Delineate the climate cycles/events in the sediment structure of the uppermost sequence; spatially, through the physical properties of the sediment; and, temporally, through the thermal and sedimentation history (in conjunction with the tasks of sub-project D).





    1. Workplan



    2. We propose to collect data during a joint cruise to be carried out in 1997, in two key-areas: in a proximal area (Ionian abyssal plain/Mediterranean ridge/Hellenic Trench, see figure) and in a distal area (Malta Trough/Malta Plateau/Malta Escarpment/Ionian Abyssal Plain, see figure). We will measure physical and chemical parameters in the water column, brines and sediments in the two key-regions, with the specific target of monitoring space and time variability of the parameters responding to the climate variability at the mentioned time scales. We intend to achieve deep penetration into the sediment (at least 10 m deep), to carry out temperature and heat flow measurements and appropriately sample for geochemical and biological analyses. The acquired data will be compared and integrated with the results of the POEM and MEDRIFF cruises, as well as with the program proposed by the companion SINAPSI cruise (Task B.5). Other ship opportunities and synergy are forseen with the European Community Programs, within MAST III and ENVIRONMENT, that will certainly increase the probability of acquiring more data in different places, and at different times. Working areas, specific objectives, methods and planning, participation to cruises with similar scientific objectives will be jointly agreed.

    3. In this view, an application for Urania ship-time has been submitted for late summer 1997.



    4. Products



    • Definition of critical areas/basins of the Mediterranean with respect to climate variability based on available data and results, mainly those recently collected within the large cooperation projects.

    • Measurements of thermal conductivity, thermal gradients, together with thermal transients at the seafloor. Heat flux, conductive and convective regimes and fluid flow velocities will be estimated.

    • Assessment of biological parameters (planctonic and benthic foraminifers, pteropods, coccoliths, diatoms, radiolarians) to be used as proxies of the oceanographic features. The true mechanisms of formation of laminae recovered in the anoxic sediments will be investigated with two different approaches: 1) the incoming sedimentary record (Subtask B4.2), and 2) the comparison with data obtained from the older sediments (Holocene/Late Pleistocene) in cores. The time series of paleoceanographic and environmental changes will be integrated with analysis on biota.

    • Reconstruction of climate cycles/events in the sediment structure of the uppermost sequence by integrating physical properties and fluxes of particles and related chemical species in the sediment, their space and time variability, with the thermal and sedimentation history (in conjunction with the tasks of sub-project D).





    1. Description of the team



    2. Institute Personnel Position Man/month

    3. DINMA, Trieste Bruno Della Vedova Researcher 6

    4. Giulio Pellis Researcher 6

    5. Guido Meton Technician 4

    6. Fabrizio Feripo PhD Student 4

    7. To be funded PhD Student 14

    8. DISTER, Milano Cesare Corselli Associate Prof. 4

    9. Simona Bianchi PhD Student 14

    10. Speranza Principato PhD Student 10

    11. Curzio Malinverno Technician 4

    12. To be funded PhD Student 14

    13. Agostino Rizzi, CNR Technician 2

    14. OGS, Trieste Angelo Camerlenghi Scientist 6

    15. Umberta Tinivella Part-time res. 4

    16. Roberto Laterza Technician 4

    17. Paolo Scarazzato Researcher 6

    18. Paolo Vismovich Technician 4

    19. To be funded PhD student 14









      1. Financial budget *

      1. Total

      1. 1997

      1. 193

      1. 1998

      1. 145

      1. Total

      1. 338

    20. *All costs are in Millions of Lire







    21. Budget allocated to each team and detailed explanation of costs



    22. 1997

    23. UNI-TS UNI-MI OGS-TS

    24. B: Consumabl. 22 17 7

    25. Transport. 7 7 2

    26. Insur.&Pers. 4 2 4

    27. Personnel 27 * 27* 27*

    28. Travel 18 (n=6) 14 (n=6) 8(n=3)

    29. TOTAL 78 67 48

    30. * Cost for an additional Ph.D. Student at the University



    31. 1998

    32. UNI-TS UNI-MI OGS-TS

    33. B: Consumables 7+10* 7+8* 7+3*

    34. Personnel 27 * 27* 27*

    35. Travel 10 7 5

    36. TOTAL 54 49 42

    37. * Additional costs to repair damages occured during the first URANIA97 cruise and for additional processing.









    38. Task B.4.2 Short time scale (seasonal. interannual, decadal) biogeochemical responses of the ecosystem to the climatic change: benthic pelagic coupling in the affected area of theEastern Mediterranean basin.

    39. Principal scientist: Paola Giordani CNR/IGM Bologna



    40. Background

    41. The target of task B4.2 is to investigate short-term (seasonal and interannual) responses of the marine ecosystem to this change, i.e. in the cycling processes of carbon and related elements occurring on the same time scale of the presently observed climatic change: production, transformation and preservation of organic matter in water and surface sediments.

    42. Carbon cycling starts from photosynthetic production of particulated orgamic matter (POM), which is subsequently transformed into other POM, DOM (dissolved organic matter) and inorganic species. Both POM and DOM can either be consumed and enter the food chain or fall out of the photic layer and sink to the sea floor. The more reactive organic matter is a mixture of metabolic products, including proteins, carbohydrates and and lipids, which become dissolved through microbial activity and are afterwards converted to CO2. Laboratory and field experiments on degrading algal materials indicated turnover times in the range 0.01 to 0.7 years, suggesting that specific classes of organic compounds differ in their resistance to degradation and react at different rates (Henrichs and Doyle, 1986; Emerson and Hedges, 1988; Harvey et al., 1995).

    43. Downward fluxes of particulate organic matter largerly depend on the production pulses and are characterized by strong seasonal fluctuations. The biochemical composition and sedimentation rates may change while sinking, because they depend on the diameter of the particles, which might increase by aggregation or decrease by bacterial consumption. These particles are also carriers of bacteria and protozoans to the sediments, where they represent a food source to the benthos.

    44. The study of these processes are nowadays based on the use of sediment traps, since they allow time-series collection of solid particles falling out of the photic zone down to the benthic boundary layer. Physical and chemical properties of these particles moving in the water column depend on the processes occurring in the water above the trap and can be compared with those deposited on surface sediment.

    45. Two sediment traps, collecting falling particles below the photic zone and above the sediment interface, allow the assessment of fluxes of biological materials and of their preservation in the sediments. The contemporary estimates of benthic fluxes, from mineralisation and burial processes, would allow to calculate mass balances for organic carbon and other elements involved in its cycling, like nutrients and redox-sensitive metals (Fe and Mn). Inferences could be extended back over geological time scales. Bacterial decomposition of degradable organic matter drives diagenetic processes, both in bottom waters, in contact with the sediments, and below the sediment water interface. Temperature and redox conditions of the reaction environment strongly affect mechanisms, kinetics and products. Temperature increases the microbially mediated reaction rates, whilst anoxic conditions seem to imply different and slower reaction pathways, when compared to oxic, typical of surface pelagic sediments.

    46. The characterisation of dissolved and particulated organic matter, as related to reactivity and reaction pathways, is therefore considered a basic scientific objective, because of its controlling effect on diagenetic reaction products over different time scales. It is accepted that the transformation of particulated into dissolved organic matter is a common step of both metabolic pathways. The organic carbon content will therefore be determined both in the sediments and in the bottom and pore waters, and the molecular complexity of the dissolved organic matter will be investigated through the measurements of optical parameters, i.e. fluorescence and absorbance. Preliminary results from an investigation, carried out in Adriatic sediments, indicate these parameters as potentially effective tools in differentiating reaction products from contrasting environments (Seritti et al., 1997). Microbial populations and efficiency will be assessed through analysing enzymatic activities and related biochemical compounds (ATP, DNA, lipids, carbohydrates, proteins), adapting standard methods to the extreme anoxic and salinity conditions. Contemporary sediments for geochemical and stratigraphic studies ( i.e. box cores and long cores) will be sampled..

    47. The selection of the experimental site is a crucial point, having to be the result of a convenient compromise among sometimes contrasting theoretical and practical requirements. Ideally it should be a deep station sited in the Ionian sea, on the main pathway of the water masses flowing westwards from the Eastern basin, not too far from the Italian coast, because of the needed periodical maintenance trips. Most of the basic data for this site selection task will be provided by the POEM-BC Program (October ‘91-April ‘92 cruises), beside the input from the first Sinapsi cruise, scheduled in November-December ‘97. A mooring array, equipped with traps and current meters, is at present deployed at site I1 (38°31’,26 Lat N; 17°58’,86 Long E), in the Western Ionian sea, within the frame of the EU MATER Project, WP 3. The maintenace of the array together with oceanographic physical, chemical and biological surveys are scheduled with a resolution time of six months. When available, the data set from this station, which will be working untill February ‘99, will provide an extreemely useful reference for the task, if not the right experimental site, as the selective criteria of the MATER Project were different.

    48. We should however take into account that from the results of preliminary oceanographic surveys, one of the deep hypersaline anoxic basins, recently discovered along the Mediterranean Ridge (MEDRIFF Consortium, 1995a, 1995b; Corselli et al., 1996), seemed to offer favourable conditions in this notably oligotrophic area (Dugdale and Wilkerson, 1988). Two time series sediment traps were infact deployed for three years in the Bannock Basin to compare the total material fluxes, and their preservation, under oxic and anoxic conditions. The results showed a clear seasonal and likely interannual pattern and also indicated that geochemical analysis and temperature measurements within the sediment could reveal the evolution of past climate-related changes at seasonal and interannual variability. So, even though the study of a second site is not possible, at least a yearly survey for sediment collection and diagenetic studies would greatly help this study, by comparing the updated results with the data set referring to the period before the onset of the lately discovered climatic change, in the Eastern Mediterranean basin.



    49. Scientific objectives



    • To assess the quantitative and qualitative variability of downward fluxes of biogenic and non-biogenic particulate matter in relation to climatic factors, both on seasonal and interannual time scales. The study will be carried out 1) by deploying sediment traps -sea. 2) studying the variation of fluxes through the sedimentary record.

    • To achieve sediment chronology using natural radionuclide decay series and estimate accumulation rates as a key parameter to calculate burial fluxes and in the sediments in relation to to water-particle interaction processes, lateral and downward fluxes of particulate matter, and estimate sediment accumulation rates.

    • To investigate sediment pore waters and solid phase composition, in order to assess the effects of lateral transport and bioturbation on the extent of benthic pelagic coupling and early diagenesis on the composition of deposited materials.





    1. Workplan



    • To run CTD hydrocasts, collect rosette samples for dissolved nutrient (ITT), alkalinity (IGM), DOC (IB), suspended matter (IBM), phytoplankton analysis and biomass (IB) in the water column.

    • To estimate primary production rates at the experimental site by C in-situ incubation technique at the experimental site (ENEA).

    • To recover particulate samples collected by time series sediment traps over a long period at a deep Ionian site (near source area). This implies the deployment of a mooring equipped with two sediment traps and two currentmeters located below the photic zone and above the seawater-sediment interface (IGM, IBM).

    • To collect sediment cores and sediment-bottom water systems during the two major cruises in anoxic and oxic basin sites.

    • To sample pore waters and carry out on board dissolved nutrient and alkalinity analyses in the pore waters; to collect and properly store pore water and solid phase samples for later sedimentological, mineralogical and chemical analyses





    1. Products



    2. Water samples



    • primary production analysis (ENEA)

    • phytoplankton analysis (IBM)

    • dissolved nutrients (ITT)

    • alkalinity (IGM)

    • suspended matter characterization (IBM)

    • DOC (IB)



    1. Trap samples:



    2. The number of analyses is severely restricted by the quantity of samples, that will be collected so that priorities have to be decided in advance.



    • determination of major constituent fluxes: organic carbon, biogenic silica, carbonates and lithogenic fractions (IGM, IBM).

    • Determination of 1413C/12C and 15N/14N isotopic ratios (ENEA)

    • characterisation of labile organic carbon: lipids, proteins, carbohydrates and nucleic acids (UNIGE),

    • determinations of Pigments by HPLC (UNIGE).

    • investigation of 230Th (228Th and 232Th), 210Pb, 210Po (IGM).



    1. Sediment core samples:



    2. a) Pore waters

    • determination of dissolved nutrients (phosphate, nitrate, nitrite ammonia silicate, sulfate, sulfide, ITT) and alkalinity (IGM);

    • determination of DOC and optical properties (absorbance, fluorescence) (IB);

    • determination of dissolved metals (iron and manganese and trace elements) (IGM,UNIVE)



    1. b) Solid phase

    • determination of organic carbon, total nitrogen and sulfur, biogenic silica, phosphates, carbonates and lithogenic fractions,grain size and mineralogical analyses , determination of major, minor and trace elements (IGM, UNIVE).

    • investigation of 230Th, 210Pb, 137Cs and 14C to estimate sediment accumulation rates (IGM)

    • biochemical composition of sediment organic matter: lipids, corbohydrates and proteins (UNIGE)

    • bacteriological analyses: bacterial abundance biomass and production; enzymatic activity, ATP (UNIGE)





    1. Sediment water systems



    • To assess the oxic vs anoxic degradation pathways of biogenic organic matter, joint experiments (UNIGE, IB, IGM, UNIBO) will be carried out in the lab in a series of artificial sediment-water systems, kept in the dark and at the in-situ temperature. Phytodetritus from artificial cultures composed with diatoms and dynophlagellates of the same species as those analysed during the survey. Microbiological, chemical analyses will be carried out in water, sediment and pore water samples



    1. The above estimates will be used to produce comprehensive models of the physical processes and their time-variability in the two key regions





    2. Description of the team



    3. Institute Personnel Position Man/month

    4. IGM/CNR, Bologna Paola Giordani Research Scientist 4

    5. Stefano Miserocchi Research Scientist 4

    6. Mauro Frignani Research Scientist 3

    7. Carlo Savelli Research Scientist 2

    8. Enver Lipparini Technician 3

    9. To be funded junior scientist 14

    10. IBM/CNR, Venezia Sandro Rabitti Research Scientist 4

    11. Alfredo Boldrin Research Scientist 4

    12. Giani Penzo Technician 2

    13. junior scientist funded by task B.5 6

    14. ENEA/AMB.CAT.FRAL,

    15. Bologna Antonella Malaguti Research Scientist 3

    16. ITT/CNR, Trieste Giuseppe Civitarese Research Scientist 4

    17. Laura Strada junior scientist 4

    18. Università di Genova Mauro Fabiano Professor 4

    19. To be funded junior Scientist 14

    20. Paolo Povero Researcher

    21. Cristina Misic Researcher

    22. IB/CNR, Pisa Alfredo Seritti Research Scientist 2

    23. Rossana Del Vecchio Junior Scientist 2

    24. Luciano Nannicini Technician 2

    25. Università di Venezia Giancarlo Rampazzo Researcher 4

    26. Mario Pistolato Technician 4

    27. Università di Bologna Laurita Boni Associated Professor 4

    28. Federico Lucchini Associated Professor 4





    29. Budget allocated to each team and detailed explanation of costs



    30. 1998

    31. IGM/CNR ENEA IBM/CNR ITT/CNR IB/CNR UNIGE UNIVE UNIBO

    32. B: Consumables 20 10 15 10 12 15 15 15

    33. Personnel 27* 27*

    34. Travel 10 3 6 5 3 10 5

    35. Total 57 13 21 15 15 52 20 15





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