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Povzetek: Deskriptor 1: Biotska raznovrstnost se ohranja. Kakovost in prisotnost habitatov ter razporeditev in številčnost vrst so v skladu s prevladujočimi fiziografskimi, geografskimi in podnebnimi pogoji. »Presojo je treba opraviti na več ekoloških ravneh: na ravni ekosistemov, habitatov (vključno z njimi povezanimi združbami na nivoju biotopov) in vrst, ki so upoštevane v strukturi tega dela ob upoštevanju točke 2 dela A. Za nekatere vidike tega deskriptorja je potrebna dodatna znanstvena in tehnična podpora. Pri obravnavi širšega obsega deskriptorja je treba ob upoštevanju Priloge III k Direktivi 2008/56/ES določiti prioritete med elementi biotske raznovrstnosti (vrste, habitati in ekosistemi). To omogoča prepoznavanje tistih elementov in območij, kjer vplivi in grožnje nastajajo, poleg tega pa podpira opredelitev ustreznih kazalcev med izbranimi merili, primernimi za zadevna območja in elemente biotske raznovrstnosti. Obveznost regionalnega sodelovanja iz členov 5 in 6 Direktive 2008/56/ES je neposredno povezana z izbiro elementov biotske raznovrstnosti znotraj regij, podregij in pododdelkov, kjer je mogoče, pa tudi z vzpostavitvijo referenčnih razmer v skladu s Prilogo IV k Direktivi 2008/56/ES. Modeliranje z uporabo platforme geografskega informacijskega sistema je lahko uporabna podlaga za določanje območja razširjenosti elementov biotske raznovrstnosti ter človekovih dejavnosti in pritiskov zaradi teh dejavnosti, ob upoštevanju, da se vse mogoče zajete napake ustrezno ocenijo in opišejo ob uporabi rezultatov. Ti podatki so pogoj za ekosistemsko upravljanje človekovih dejavnosti in za razvoj s tem povezanih prostorskih orodij.«
Ključne besede: morje, obalno morje, onesnaževanje morja, plankton, hranilne snovi, ekološki parametri, onesnažila, onesnaževalci, biocenoze, okvirna direktiva o morski strategiji, poročila, onesnaženost, kvaliteta okolja, morska strategija, deskriptorji
Objavljeno v DiRROS: 16.09.2024; Ogledov: 817; Prenosov: 652
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Povzetek: Jellyfish are becoming an increasingly important component of studies of the global marine environment, as their frequent mass phenomena affect ecosystem performance and have economic and health consequences. Recent research has focused primarily on mass occurrences of scyphozoans and ctenophores, while less attention has been paid to hydromedusae blooms, which can also have significant impacts on the marine ecosystem with economic consequences. Like many members of the Scyphozoa and Ctenophora, Aequorea species can be numerous and form blooms. Based on surveys from 2000 to 2020 and information provided by marine professionals, we examine the (multiannual) variability, seasonality, and spatial distribution patterns of the poorly studied temperate species Aequorea cf. forskalea (Hydrozoa: Leptothecata). We hypothesized that this macrogelatinous jellyfish with a bipartite life cycle (benthic polyps and planktonic medusae) is sensitive to seasonal and long-term temperature fluctuations, particularly because temperature has been shown to play a critical role in mediating transitions in the life cycle of cnidarians. The cold-water affinity of A. cf. forskalea was confirmed by a significant negative correlation with temperature and the most frequent occurrence during the winter-spring period. For the northern Adriatic (Gulf of Trieste), sea temperature data and semi-quantitative plankton data are available for the first decade of the 20th century, allowing comparison of the historical data (1900-1911) with our current data set. Compared to historical records, the current occurrence of A. cf. forskalea differs significantly. With the warming of the northern Adriatic Sea since the beginning of the 20th century, the current phenology of A. cf. forskalea has changed, probably related to the delayed production of medusae by hydroids in autumn, the absence of medusae in this season and their less frequent occurrence in winter.
Ključne besede: hydromedusae, blooms, long-term monitoring, multiannual variability, Mediterranean Sea
Objavljeno v DiRROS: 31.07.2024; Ogledov: 605; Prenosov: 194
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Povzetek: Addressing coastal risks related to sea storms requires an integrative approach which combines monitoring stations, forecasting models, early warning systems, and coastal management and planning. Such great effort is sometimes possible only through transnational cooperation, which becomes thus vital to face, effectively and promptly, the marine events which are responsible for damage impacting the environment and citizens' life. Here we present a shared and interoperable system to allow a better exchange of and elaboration on information related to sea storms among countries. The proposed integrated web system (IWS) is a combination of a common data system for sharing ocean observations and forecasts, a multi-model ensemble system, a geoportal, and interactive geo-visualisation tools to make results available to the general public. The multi-model ensemble mean and spread for sea level height and wave characteristics are used to describe three different sea condition scenarios. The IWS is designed to provide sea state information required for issuing coastal risk alerts over the analysed region as well as for being easily integrated into existing local early warning systems. This study describes the application of the developed system to the exceptional storm event of 29 October 2018 that caused severe flooding and damage to coastal infrastructure in the Adriatic Sea. The forecasted ensemble products were successfully compared with in situ observations. The hazards estimated by integrating IWS results in existing early warning systems were confirmed by documented storm impacts along the coast of Slovenia, Emilia-Romagna and the city of Venice. For the investigated event, the most severe simulated scenario results provide a realistic and conservative estimation of the peak storm conditions to be used in coastal risk management.
Ključne besede: sea storms, integrated web system (IWS)
Objavljeno v DiRROS: 19.07.2024; Ogledov: 294; Prenosov: 210
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Povzetek: One of the obstacles to detecting regional trends in jellyfish populations is the lack of a defined baseline. In the Adriatic Sea, the jellyfish fauna (Scyphozoa and Ctenophora) is poorly studied compared to other taxa. Therefore, our goal was to collect and systematize all available data and provide a baseline for future studies. Here we present phenological data and relative abundances of jellyfish based on 2010–2019 scientific surveys and a “citizen science” sighting program along the eastern Adriatic. Inter-annual variability, seasonality and spatial distribution patterns of Scyphomedusae and Ctenophore species were described and compared with existing historical literature. Mass occurrences with a clear seasonal pattern and related to the geographical location were observed for meroplanktonic Scyphomedusae Aurelia solida, Rhizostoma pulmo, and to a lesser extent Chrysaora hysoscella, Cotylorhiza tuberculata and Discomedusa lobata. Holoplanktonic Pelagia noctiluca also formed large aggregations, which were seasonally less predictable and restricted to the central and southern Adriatic. Four species of Ctenophora produced blooms limited to a few areas: Bolinopsis vitrea, Leucothea multicornis, Cestum veneris and the non-native Mnemiopsis leidyi. However, differences between Adriatic subregions have become less pronounced since 2014. Our results suggest that gelatinous organisms are assuming an increasingly important role in the Adriatic ecosystem, which may alter the balance of the food web and lead to harmful and undesirable effects.
Ključne besede: jellyfish phenology, hydrobiology, long-term changes, Mediterranean Sea
Objavljeno v DiRROS: 19.07.2024; Ogledov: 310; Prenosov: 206
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Povzetek: In the Mediterranean Sea, the Strait of Messina (MS) is a very peculiar area, connecting highly different regions and representing a privileged observatory for an early comprehension and assessment of ecosystems shifts. It is hypothesized that the outbreaks observed near the coast of many sites in the Mediterranean Sea may be the result of transport of permanent populations of P. noctiluca in pelagic waters to the coast, caused by specific hydrodynamic conditions. By both visual observations and numerical experiments our objective is twofold: (A) to help clarify whether the basin of the Aeolian Islands Archipelago (AIA), in the Southern Tyrrhenian Sea (STS), may be the site from which large populations of P. noctiluca are transported to the MS, and (B) to evaluate whether the upwelling turbulent system of the MS can be an energetic opportunity for this species. It should offer a rich habitat without jeopardizing the overall survival of the population, that is subject to stranding due to strong currents. Although very different, the two involved ecosystems (AIA and MS ) are complementary for the success of Pelagia noctiluca life cycle. Outputs obtained by coupling the 3D hydrodynamic model (SHYFEM) with a Lagrangian particle tracking model support the hypothesis of a connectivity between these two ecosystems, particularly in the first half of the year, indicating the coastal areas around the AIA as potential optimal source location for Pelagia larval stages. We support the very attractive hypothesis that two connected systems exist, the former one favours Pelagia's reproduction and acts as a nursery and the latter favours its growth due to higher productivity. We speculate that the reproductive population of the AIA is not permanent, but is renewed every year by individuals who have fed and quickly grown in the MS and who are passively transported by downwelling along canyon "corridors".
Ključne besede: coastal systems, coastal water, Tyrrhenian Sea
Objavljeno v DiRROS: 17.07.2024; Ogledov: 310; Prenosov: 232
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