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Oil slick detection by synthetic aperture radars (SAR) is a proven and commonly used operational technique, which showed that the seas of the Mediterranean are often polluted by oil and oily products. For the period 2003-2011, the Envisat and Radarsat-1 SAR images were available for analysis, thanks to the several projects. About 300 SAR images have been analysed over the Middle and Southern Adriatic Sea, in order to detect marine oil spills and other phenomena causing similar signatures. Analysing many oil spills detected in the Adriatic Sea, their sizes were determined between 0.1 km2 and 108 km2. Most of the spills were located along the main shipping routes, especially in the ship corridor along the Adriatic Sea axis. They were, most probably deliberate slicks released from ships during transportation or fishing operations, while suspected source of the largest spills is tank washing or illegal discharges., Detekcija uljnih mrlja sintetičkim satelitskim radarom (SAR) provjerena je i najčešće korištena operativna tehnika, koja je pokazala kako je Sredozemno more često zagađeno uljem i sličnim proizvodima. Zahvaljujući nekolicini projekata Envisat i Radarsat-1 SAR slike su za razdoblje 2003-2011 bile dostupne za analizu. Analizirano je oko 300 SAR slika srednjeg i južnog Jadrana, kako bi se otkrile pojave naftnih mrlja i druge pojave koje imaju sličan signal na satelitskim snimcima. Otkrivena su mnoga izlijevanja nafte u Jadranu, čije su površine bile između 0,1 km2 i 108 km2. Većina izlijevanja je smještena uz glavne brodske rute, osobito u brodskom koridoru duž osi Jadranskog mora. To su vjerojatno ulja namjerno izlivena s brodova tijekom prijevoza ili ribolovnih operacija, a najčešći slučajevi izlijevanja su pranje brodskih spremnika ili nedozvoljena pražnjenja tankova.

Fitoplanktonska zajednica je zbog svog brzog odgovora na promjene u okolišu pouzdan pokazatelj stanja okoliša i jedan je od bioloških elemenata koje za procjenu kvalitete vode propisuje Okvirna direktiva o vodama (ODV). Kako bi se testirao odgovor fitoplanktonske zajednice na antropogene pritiske s kopna, multivarijatne statističke metode korištene su za analizu koncentracije klorofila a, brojnosti i sastava fitoplanktonske zajednice u odnosu na antropogeni utjecaj i ekološke varijable kao što su temperatura, slanost i hranjive soli. Analizom su obuhvaćene postaje različitog stupnja opterećenja, a preliminarna procjena antropogenog utjecaja na istraživanim postajama je određena preko LUSI indeksa (Land Use Simplified Indeks). Multivarijatna analiza je pokazala da su koncentracije hranjivih soli nitrata i silikata pouzdan pokazatelj utjecaja slatke vode, dok su biomasa i brojnost fitoplanktonske zajednice pouzdan pokazatelj antropogenog utjecaja. Odgovor bioraznolikosti fitoplanktonske zajednice nije bio linearan, a najveća biorazmolikost zabilježena je u srednje eutrofnim odnosno mezotrofnim područjima. Kanonička analiza korespondencije identificirala je sljedeće vrste kao indikatore porasta eutrofikacije: Skeletonema costatum, Scrippsiella trochoidea, Guinardia flaccida, Leptocylindrus spp., Prorocentrum spp., Proboscia alata, Eutreptiella spp. i Pseudonitzschia spp.

Direktiva 2006/113/EZ o potrebnoj kakvoći vode za školjkaše odnosi se na kakvoću voda za uzgoj školjkaša i primjenjuje se na priobalne i prijelazne vode koje je država odredila kao vode kojima je potrebna zaštita ili poboljšanje kako bi se omogućio život i rast školjkaša i time pridonijelo visokoj kakvoći jestivih školjkaških proizvoda. Školjkaši su zbog načina ishrane veoma osjetljivi na onečišćenje vode jer prilikom filtriranja zadržavaju i akumuliraju sve mikroorganizme, organske čestice, teške metale i razna druga zagađivala. Monitoring voda za školjkaše je neophodan zbog pravovremenog sprječavanja zagađenja samih školjkaša kao i zbog zaustavljanja prijenosa onečišćujućih tvari kroz hranidbeni lanac. Određivanje voda namijenjenih za uzgoj školjkaša napravljeno je u skladu sa Direktivom 2006/113/EZ koja propisuje niz fizikalnih, kemijskih i bioloških pokazatelja koji moraju biti zadovoljeni bilo da udovoljavaju obveznim standardima ili visokim standardima tzv. «guideline» koji predstavljaju smjernice za daljnje određivanje voda pogodnih za uzgoj školjkaša. Direktivom je određena i minimalna učestalost uzorkovanja kao i metode koje se moraju koristiti za analizu određenih pokazatelja. Određene su vrijednosti sljedećih pokazatelja za morsku vodu: pH, temperatura, obojenje, količina suspendiranih čestica, salinitet, otopljeni kisik, naftni ugljikovodici, a za školjkaše maseni udjeli organohalogenih tvari, metala (As, Cd, Cr, Cu, Hg, Ni, Pb i Zn) i saksitoksina te koncentracija bakterije Escherichia coli.

The Adriatic Sea is of exceptional importance for Croatian economy as a resource for fisheries, tourism, transport and other goods. For these and many other reasons it is important to control its ecological state and preserve its biodiversity. Croatian Environmental Protection Agency together with a number of institutions has organized collection of environmental data. The reports, data and graphs can be viewed at the web (http://jadran.izor.hr/azo/).The Institute of Oceanography and Fisheries Split (IOF) and Institute Ruđer Bošković, Rovinj (IRB), are in charge of marine data acquisition and IOF is in charge for the marine database. Here we present some of the results from the last few years collected at twenty east Adriatic coastal stations and one middle Adriatic open sea station. Discussed are oxygen saturation, nutrients, chlorophyll a concentrations, suspended matter and transparency. Statistical analysis for the period 2005-2009 is compared to the long-term mean/median values. High spatial and seasonal variability of the parameters is discussed in relation to location of the stations regarding possible anthropogenic impact. Connection to the hydrodynamics is also discussed. Correlations, PCA and other analysis gave some new indications of the relations among parameters.

Morning, midday, evening and night repetitive sampling was used to demonstrate calycophoran diel vertical migration (DVM) at fixed station in the oligotrophic southern Adriatic Sea at 8 depth intervals. Of 20 calycophoran species collected, most of them inhabited layers of specific temperature and light intensity, and migrated during night. The deep species Kephyes ovata is primarily non-migratory. Typical nocturnal movements to the surface were recorded for Lensia conoidea and Sphaeronectes koellikeri. Lensia subtilis and Eudoxoides spiralis migrated toward surface in the evening but sank deeper at night. Lensia meteori and Lensia fowleri reached upper layers at midday. The DVM of Sphaeronectes irregularis was irregular and independent of diel light patterns. Though low in numbers, some calycophorans were found above the thermocline at night. For mesopelagic species, however, higher summer surface temperatures proved an effective barrier to migration above 100 m. Thus, certain species could be represented as key species of planktonic cnidarians assemblages found within a certain depth range. Though not homogenous, and while some undertake nocturnal migrations in both directions, all are interrelated by preferences of bathymetric distribution and specific DVM behavior.

How Mediterranean cyclogenesis, local topography and land-sea distribution interact to produce strong winds? How air-sea fluxes are modulated? How does the Mediterranean Sea response to the atmospheric forcing?

A set of spaceborne synthetic aperture radar (SAR) images and geographic information system (GIS) can significantly contribute to monitoring and identification of oil spills floating on the sea surface. Initially, the GIS has been proven as an excellent management tool for resources assessment, oil spill response and planning, and damage assessment, but the possibilities of GIS mapping also integrate geographical, remote sensing, oil & gas production/infrastructure data and slick signatures detected by SAR. Data from different sources such as nautical charts, geo-databases, ground truth and remote sensing data combined in GIS reveal offshore/onshore oil sources, and estimate the intensity and evolution of oil pollution. SAR and GIS together can significantly improve identification and classification of oil spills, leading to the product - oil spill distribution maps. This approach, applied successfully in different water basins, can also be applied to oil spill monitoring/ mapping in Croatian waters of the Adriatic Sea – it can contribute to understanding the spatiotemporal distribution of oil spills in the Adriatic Sea and be an ideal tool for an oil spill monitoring system. In the framework of the Croatian initiative towards regional cooperation in the Adriatic Sea, such an approach represents a good national opportunity. In this paper, the properties of SAR imagery, as the most reliable source of oil spill information, are described. The possibilities of a combined SAR-GIS approach to oil spill monitoring and GIS databases as a management tools for the protection of the Adriatic Sea are discussed.

Simple for use and cheap, transparency measurements with the Secchi disk are probably unique marine parameter of unchanged methodology since 1860 and still interesting, especially from its long term prospective. In this paper, we present long term series of transparency for the eastern Adriatic Sea. Three stations in its northern part, ten stations from the middle and three stations from the South Adriatic area were investigated. Many of these stations were sampled monthly. The stations encompass the least transparent shallow coastal bays, moderately transparent channels and the most transparent open sea areas. The oldest records are from the Najade expedition (1911-1914). The ANOVA tests were performed and annual trends of presented data were shown. Seasonal signals indicate mainly late summer as the most transparent season, and mainly winter as the least transparent period. Diverse behavior of transparency was noticed among the areas, from no trends to decreasing or increasing trends for different seasons or periods. High spatial variability of transparency rises from variable influences of natural or anthropogenic factors. The causes of spatial differences, temporal variability and trends were taken into consideration.

The MEDUZA cruises in the south Adriatic Sea have acquired a number of oceanographic data in the deep South Adriatic Pit in summer 2003. Temperature, salinity and dissolved oxygen concentrations, together with transmission, pigments and optical parameters, were measured by two multiprobes in 6-h intervals during several days. Strong quasi-diurnal fluctuations of isothermal depths were observed, being in phase with local sea level, thus indicating internal waves as important phenomenon during this cruise.

In 2000, the National Science Foundation, in union with Croatian and Slovenian science ministries, provided initial support for the international collaboration that has become Meduza project. The program was started with the goal of international collaboration. Our initial objective was simple - use this international collaboration to develop exiting scientific research involving medusae in Southern Adriatic waters. This international collaborationa has been of great importance personally and professionally to all of the investigators and institutions involved in the project, but we now ask what objective difference has the project made scientifically. We approach this question by comparing what we might accomplish at the project's outset to how we now view of research on gelatinous zooplankton because of research in the Meduza project. Work outside the also has affected our views but we describe here research produced through the project that has contributed substantially to broadening our perspectives in three major areas of investigations: modes of propulsion, mechanics of predation, and trophic significance of medusae.

This review compares historical data sets (1967-68, 1974-1976, 1993-1995)to the most recent data (2003-2004)on the composition, abundance and vertical migration of cnidarians of the deep southern Adriatic. 18 species of medusae are typical open-ocean holoplanktonic species and 6 of these were either always or frequent found in samples, namely Rhabdon singulare, Aglaura hemistoma, Persa incolorata, Rhopalonema velatum, Sminthea eurygaster, and Solmissus albescens. The most common calycohore siphonophores are Lensia subtilis, L. meteori, Eudoxoides spiralis, Sphaesonectes gracilis, and S. irregularis, followed by Hippopodius hippopus, Vogtia penthacantha, Lensia comoidea, L. fowleri, Chelophyes appendiculata, Kephyes ovata, and Bassia bassensis. Some difference in presence and abundance betwen historical and recent data are noted.

As a result of electric power market liberalization, the energy market in Croatia began to open in 2006. and continued to gradually open until July 1, 2008., which means that from that date competitive energy market is open for retail markets and all customers have the legal right to choose their electricity supplier. This paper will present initial experiences in service quality implementation in HEP Distribution System Operator (HEP DSO). Also, a vision for a future distribution system in Croatia will be discussed, with areas that will be the key for technology development and the advantages of the new electricity market.

Simple for use and cheap, transparency measurements with the Secchi disk present probably a unique marine parameter which has remained in use with unchanged methodology since 1860. Today, it is still interesting, especially from its long term prospective. In this paper we have investigated long term series of transparency data for the eastern Adriatic Sea, from the north to the south over 600km distance. For several stations, the series of transparency data span over five decades in time. The data from 20 stations were analysed: from the three stations in the north, fourteen in the middle and three in the South Adriatic Sea, of which fifteen are in the coastal areas and five from the open sea. Selected are all characteristic areas from the least transparent shallow coastal bay areas, to the most transparent as the open south Adriatic waters. The oldest records are from the Najade expedition (1911-1914). Seasonal signal is evident, with the late summer as the most transparent season, and mainly winter as the least transparent. Some stations show slightly changed seasonal course when comparing the last 10 years with the previous period. Areas show different behavior of transparency, from no trends to decreasing or increasing trends. In some coastal areas the conditions have improved recently and after decreasing, increasing transparency trends are occuring. In other areas decresing trends can be distinguished in summer period. For statistical analysis we have used only the data from stations which are sampled monthly. Since majority of the data were acquired during the summer period, for the stations with the sparse sampling only summer data were used. Shown are annual trends and variabilities and compared are seasonal courses between earlier and recent data. The ANOVA tests are performed for the raw and transformed data. High spatial variabilities of transparency point to variable influences in different areas from urban pollution or from cycles of natural factors. Causes of both, spatial and temporal variability and trends are discussed.

Multidecadal pattern of physical and chemical parameters in the Adriatic sea is mostly controlled by the climate factors throught combined effect of the heat exchange, precipitation, river runoff and water exchange across the Otranto Strait. In this paper we investigated Northern Hemisphere climate effects on the long term variability of the thermohaline structure in the Adriatic Sea during the period 1961-2008 from seasonal to interannual scale. Although the linkage between ocean temperature and salinity changes and atmospheric climatic trends exist on decadal to long-term scales, the results obtained for various basins (for example Bering Sea, Baltic and North Sea) suggest that shifts in the climate regime can be responsible for shifts in the marine hydrochemical parameters. Recent investigation in the Adriatic Sea suggest that observed shift in the thermohaline and chemical structure was controlled with northern hemispheric climate variation. While the years 1980-1986 showed an increasing trend, the years 1987-1996 where characterized by an inverse pattern of temperature, salinity and oxygen concentration. Such opposite patterns appeared linked to modifications in thermohaline circulation related to the Eastern Mediterranean Transient (EMT) whose effects prevented warm and saltier water masses intrusions into the Adriatic and reduced local temperature and salinity. Weak ventilation in the Adriatic was therefore evidenced in the lower than normal sea temperature, salinity and oxygen concentrations below the thermocline. These results indicate to connections between shifts in middle Adriatic with Northern Hemisphere climate system via changes in regional atmospheric conditions, and highlight the role of atmospheric variability may play as a triggering factor for marine ecosystem changes.

Physical and chemical characteristics of the water column and sediment at sea bass / sea bream farm located in the middle Adriatic island of Brač were investigated during 2001-2006 period. Measurements and samplings were performed at the stations inside the farm area and at the reference station, approximately 1 km distanced away from the farm. Investigated parameters in the water column were temperature, salinity, transparency, suspended matter concentration, oxygen saturation and nutrient concentrations. Parameters measured in the sediments were granulometric composition, redox-potential, organic matter, organic carbon and total nitrogen content, inorganic phosphorus (P) species concentration (biogenic apatite P, authigenic apatite P, detrital apatite P and P bound on to iron oxides and hydroxides) and organic P. Transparency in the water column at all stations followed natural seasonal course, although constantly lower values at the farm station relative to reference site indicate potential impact of fish farming on this parameter. Impact on chemical parameters were moderately expressed in the surface and middle layer of the water column through the deficiency of oxygen and increased concentrations of dissolved inorganic nitrogen, orthophosphate and urea due to fish excretion and degradation of their metabolic products. Sediment inorganic P concentrations were enhanced under the cages compared to reference site, while organic P was mainly in range of “ natural” middle Adriatic concentrations. Sequential analysis of inorganic P species showed increased portion of biogenic apatite P and decreased detrital apatite P at the farm stations related to inorganic P pool at reference station as a direct consequence of fish farming. Sediment redox-potential, granulometric composition, organic matter content, carbonates as well as organic carbon and total nitrogen content reflected natural sediment characteristics rather than fish farm influence.

Planiranje i razvoj mreže za distribuciju električne energije temeljeno je na očekivanom porastu isporučene i preuzete električne energije kroz kontinuiranu izgradnju novih te održavanje i proširivanje postojećih elektroenergetskih objekata i instalacija. Analizirajući pristup korisnika na elektroenergetsku mrežu HEP Operatora distribucijskog sustava d.o.o. (HEP ODS) provodi se u skladu sa zakonima i propisima, pri čemu su tehnički parametri određeni tako da se ne narušava standardna razina kvalitete opskrbe električnom energijom prije priključenih korisnika i ista omogući novom korisniku. U referatu je definiran postupak analize mogućnosti priključenja na niskonaponsku mrežu, i kao takav samo je dio ujednačenog načina obrazlaganja definiranih uvjeta priključenja na mrežu za distribuciju električne energije iz izdane prethodne elektroenergetske suglasnosti (PEES) ili odbijanja zahtjeva za izdavanje PEES uslijed ograničenih tehničkih ili pogonskih mogućnosti u mreži.

Liberalizacijom tržišta električna energija postaje roba kojom se trguje na otvorenom tržištu, a koja mora ispunjavati zadane kriterije kvalitete vezane uz kvalitetu isporuke, kvalitetu napona te kvalitetu usluga. Provedbom deregulacije tržišta električne energije, interesi korisnika mreže dolaze u prvi plan. Kvaliteta usluge usredotočena je na otvorenost tržišta s naglaskom na važnost uloge korisnika mreže koji određuje ulazne podatke i postavlja uvjete jedinstvenom i kompleksnom procesu unutar organizacijske strukture kao što je HEP Operator distribucijskog sustava d.o.o. U radu su navedene sve dostupne usluge koje je HEP ODS d.o.o. dužan pružati korisnicima mreže, kako u djelatnosti distribucije tako i u djelatnosti opskrbe te su opisani načini poboljšanja kvalitete usluga.

U radu je opisan oceanografski mjerni sustav s plutačama (AMOS) razvijen u sklopu Nacionalnog programa praćenja ekološkog stanja Jadranskog mora (projekt Jadran)

We investigated Northern Hemisphere climate effects on the long term variability of the marine ecosystem in the middle Adriatic Sea during the period 1961-2005. Air temperature, precipitation, evaporation, air-sea fluxes and the North Atlantic Oscillation index covary with the patterns observed in temperature and salinity data. The use of a sequential algorithm for regime shift detection (SARS) applied to the primary production and sardine/anchovy ratio revealed three periods with significantly different mean levels of productivity: 1961-1979, 1980-1996 and 1997-2002. Moreover, the years 1980 to 1996, with the highest primary production, showed contrasting periods of productivity. While the years 1980-1986 showed an increasing trend, the years 1987-1996 were characterized by an inverse pattern. Such opposite patterns appeared to be linked to modifications in thermohaline circulation related to the Eastern Mediterranean Transient (EMT) whose effects prevented warm and nutrient rich water mass intrusions into the Adriatic and reduced productivity. Weak ventilation in the Adriatic was also evident in the lower than normal sea temperature and oxygen concentrations below the thermocline. These results provide evidence on connections between shifts in primary production in the middle-Adriatic with the Northern Hemisphere climate system via changes in regional atmospheric conditions, and highlight the role atmospheric variability may play as a triggering factor for ecosystem-wide changes.

The introduction of electricity market and process of liberalization put uses interests into focus, such as ability of procuring cheaper electricity and ability of producing electrical energy of better quality. Apart from that, the privatization of electric power system segments attracts the interest of capital and profit making, which is in conflict with users interests. Therefore it is necessary to monitor the quality of electricity supply within requirements of quality management systems.

Eastward shift in the sea level pressure pattern associated with interannual NAO variability, that occurred around 1980, is a consequence of the increasing temperature trend during the last decades. This hemispheric scale shift corresponds with regional atmospheric pattern of the area of the Adriatic Sea, which, controlled by the boundary layer conditions and circulation, change local sea conditions, productivity, fish and cephalopods stock in the area. Climate-fish and cephalopods stock connection observed in the period 1961-2003 was documented using principal component analysis and correlation technique, revealing that regional atmospheric forcing was significantly correlated with hemispheric climate, and that it was responsible for local fish and cephalopods stock steady and abrupt changes.

Samples of surface sediment layer (0-2 cm) were col-lected at 39 locations along the eastern Adriatic coast (Croatia) in August and September 2005. Results of granulometric composition, organic matter, carbonate, organic carbon content and phosphorus concentration in sediments were subject to correlation and cluster analysis. The examined stations represent the areas of different trophic status and environmental conditions for sediment particles settling. Sand was predominant grain size sedi-ment fraction (53± ; ; 34%) and it was negatively correlated with organic matter content (3.84± ; ; 2.40%). Carbonate content in sediments (47± ; ; 14%) was not correlated to granulometric composition due to different geological origin of the North and Middle Adriatic sediments. Organic matter affinity to smaller sediment particles resulted with higher C-ORG values in fine-sized sediments. Total phosphorus concentrations (13.4± ; ; 4.6 µ ; ; mol g-1) were positively correlated to fine-sized sedi-ments and negatively to carbonates. Cluster analysis of the all investigated parameters indicated the granulometric composition as a leading factor that influences other sediment characteristics of the eastern Adriatic area.

European shelf seas have undergone significant modifications, including ecosystem-wide shifts from cold-adapted to warm adapted communities. Empirical evidence has been found suggesting that the linkage between winter regional hydroclimate in European shelf seas (North, Baltic, western Mediterranean and central Adriatic) over the period 1950 to 2000 with the North Atlantic Oscillation (NAO) is discontinuous likely as consequence of the long term variations of phase and intensity of the NAO. The long term variations and wavelet power spectrum (not shown) of hydroclimate conditions in the northern seas (i.e. North and Baltic Seas), as well as in southern ones (western Mediterranean and central Adriatic, showed synchronous changes suggesting coherent variations at regional scales in the two areas. In addition, the quantitative synthesis of original investigations on climate effects on Europeanshelf seas shows a clear signature of the NAO on abundance/biomass changes in plankton communities, either phytoplankton or zooplankton, although the strength of the signal on the latitudinal gradient with the southern areas (i.e. western Mediterranean) further linked to subtropical climate variations. Owing to the key role plankton play in marine ecosystems (i.e. target food for small pelagic fish, e.g. anchovy, sprat) this work provides insights into the role of hemisphere-wide climatic processes on the ecological functioning of regional food webs.

First results of extensive ADCP and CTD measurements, performed in the Adriatic shelf-break area between February and September 2006, are presented. Pronounced diurnal oscillations were observed, apparently related to internal tides and periodic upwelling and downwelling events. Moreover, inertial oscillations were documented. Finally, summertime change of the east-coast inflow to the Adriatic was recorded, lasting only one month at two ADCP stations, three months at one station.

Rad predstavlja rezultate praćenja utjecaja rada uzgajališta ribe područja srednjeg Jadrana na fizikalno kemijske i biološke parametre u vodenom stupcu i sedimentu.

The paper aims to demonstrate water optical properties in the Middle and Southern Adriatic. Investigated are particular locations in the channel and bay areas as well as the open sea. The research is based on the spectral measurements of daylight intensity, performed with the profiling radiometer PRR800 (Biospherical Instruments Inc.). High resolution measurements of downward irradiance and upward radiance were carried out at 14 wavelengths from UV to visible light (340 ; 380 ; 412 ; 443 ; 465 ; 490 ; 510 ; 532 ; 555 ; 589 ; 625 ; 665 ; 683 and 710 nm) together with the PAR (400-700 nm) and natural fluorescence measurements. Among the measurements performed through 2003-2006, selected were those that demonstrate high spatial variability of optical characteristics, pointing to the different exposure of the areas to the coastal pollution or to the influence of clear open sea waters. Optical water types were determined for the selected stations demonstrate large variability. The comparison is performed with the optical water types established by Jerlov (1976), from PAR attenuation measurements and from irradiance spectra at 10m depth. The open sea stations and some channel stations show characteristics of unpolluted sea, like clear oceanic waters of optical types I or II. Stations located in semi-enclosed bays and the stations exposed to the river runoffs have characteristics of coastal optical water types, spanning over a wide range of optical types.

Vertical irradiance attenuation coefficients were determined for 14 wavelengths from recent spectral irradiance measurements in the South Adriatic, during Meduza experiment. The first results enabled optical and thermohaline characterization of the water masses.