Search Results (37)

A series (n = 22) of glasses from the site Kapucinski vrt (garden of the Capuchin monastery, 5th–17th c. CE) in Koper (Capodistria), a port town in the northern Adriatic, was measured using a combined PIXE and PIGE method. Koper has been continuously populated since the late Roman period, with a rich medieval history, thus offering an opportunity to study Early Medieval glass. Stemmed goblet fragments, in the original publication dated between the 6th–9th centuries CE, and several other vessel types (beakers and flasks or bottles and lamps) were selected for analysis. The measurements were expected to show the trends in glass production and consumption from Late Antiquity until the Middle Ages, notably the transition between natron to plant ash glass and the supply of fresh glass. Among the set of 22 glass vessel fragments, both natron and plant ash glass were identified. For finer classification, we relied on a newly developed method of Euclidean distances with respect to major concentrations. Natron glass of the types Foy 2.1 (9 examples), Magby (2 examples), and Levantine I (Apollonia; 2 examples) was found. Two glasses remain undetermined but testify to an Egyptian origin. Most natron glasses show signs of recycling. Among the three unrecycled glasses (about 20% of the whole set), there are two examples of Levantine glass and a Magby glass lamp; this may indicate a modest supply of fresh glass during the period. Plant ash glass may be attributed to the Early or High Middle Ages, exploiting the purified alkalis of the Levantine coasts (known as alume catino in later Venetian glassmaking), and the admixture of impurities in the siliceous sands suggests the circulation and consumption of glass that was produced and traded in the eastern Mediterranean since the 10th century CE. Full article

Increasing risks from sea-level rise and other climate impacts call for a focus on physical coastal attributes, emphasising the need for region-specific tools to address the vulnerability of different coastlines. This paper presents the development of a Physical Coastal Vulnerability Index (PCVI) for climate change impacts like sea-level rise, erosion, and storm surges, which is applied to the Croatian coast of the Istrian Peninsula. The methodology provides a detailed, site-specific vulnerability assessment focusing on physical parameters such as coastal aspect, slope, elevation, and coastal type. Eight different grid cell sizes were evaluated to map the coastline, demonstrating, as expected, that smaller cells (5 × 5 m) captured more detailed variability in vulnerability. Among seven evaluated calculation methods, the second root of the self-weighted arithmetic mean (M3) proved the most effective, emphasising high-risk regions by prioritising critical physical variables. The results show that the western Istrian coast is more vulnerable due to its morphological properties, with nearly 50% of highly vulnerable coastlines. This paper emphasises the importance of using high-resolution grids to avoid oversimplification of vulnerability assessment and recommends using PCVI as a basis for further socio-economic assessments. The proposed PCVI methodology offers a framework that can be adapted to assess the physical vulnerability of the eastern Adriatic coast and other similar coastal regions, particularly in the Mediterranean, enhancing its relevance for integrated coastal zone management and global climate change mitigation strategies. Full article

This study focuses on the analysis of sediment core retrieved from the deepest part (25 m) of Pirovac Bay. A long sedimentary sequence (7.45 m) supplemented by a shorter sediment core (1.45 m) from a shallower part of the bay was analyzed for sedimentological, mineralogical, geochemical, and micropaleontological (ostracod) parameters. The sediment thickness above the underlying karst paleorelief (karstic bedrock) is up to 12 m. Sediments recorded a transition from a freshwater to a marine environment starting from post-Neapolitan Yellow Tuff tephra sedimentation. First, the floodplain developed in Pirovac Bay, with intermittent pools and ponds, followed by wetland environment. The formation of a shallow freshwater paleolake during the Middle Holocene at 10 cal kyr BP was enabled by the rising sea level and high freshwater input from the karstified underground from the adjacent Lake Vrana (Biograd na Moru). The onset of marine intrusions through the karstified underground is evident with formation of a brackish lake in the Pirovac Bay basin. Marine transgression and flooding of the bay occurred at 7.3 cal kyr BP, evidenced by the geochemical and ostracod parameters, providing crucial insights into the dynamics of coastal inundation under past climate change. Intriguingly, freshwater ostracod species were still present in the marine sediments, brought into the bay from Lake Vrana through surficial canal Prosika and groundwater discharge (numerous estavelles) along the northeastern shores of the bay, proving their mutual influence. This submerged Holocene freshwater paleolake, reported here for the first time, underlines the sensitivity of coastal karst systems to the rise in sea level and serves to stress how important understanding of these processes is for effective management in coastal zone and climate change adaptation strategies. The findings provided evidence supporting the existence of coastal marine basins as freshwater lakes prior to being flooded by seawater as a consequence of the Holocene post-glacial sea level rise. Full article

The presence of the white shark (Carcharodon carcharias) in the Mediterranean Sea is well documented, but mainly through historical and opportunistic records. Historically, the Adriatic Sea, particularly its eastern coastline, was considered a hotspot for white sharks, with relatively frequent reports of juvenile specimens suggesting a potential nursery area. However, since the second half of the 20th century, the abundance of white sharks in the Adriatic has experienced a dramatic decline, with the last confirmed sighting recorded in 2011. In this study, we report the recent capture of a young-of-the-year (YOY) white shark off the Croatian coast, previously misidentified as a porbeagle shark (Lamna nasus). In addition, we revisit historical records of white sharks in the Adriatic Sea to assess whether this region can be considered a nursery area. Our findings highlight significant gaps in the understanding of white shark spatial ecology and reproductive biology in the Mediterranean Sea. Furthermore, this study emphasizes the critical role citizen science and public engagement can play in documenting occurrences of these elusive and endangered predators, offering valuable insights for future conservation efforts. Full article

The fortified hilltop settlement of Monkodonja, located near Rovinj on the west coast of Istria, Croatia, provides insight into Bronze Age occupation and conflict in the Adriatic region. Established around 2000 BC, as evidenced by a series of C14 dates from human and animal bones, the settlement experienced significant construction phases, particularly in its defensive architecture. Its earliest fortifications, built with limestone blocks using dry-stone wall techniques, date to the 19th century BC, with major expansions in the 16th century BC, where the primary wall was doubled in width and reached over 3 m in thickness. Monkodonja’s architectural complexity, notably the West Gate and Acropolis fortifications, and certain types of artifacts reveal influences from southern regions such the eastern Aegean. However, the settlement appears to have met a violent end around the 15th century BC, suggested by destruction layers, widespread burning, and the presence of weapons such as a lance tip, bronze axe, and slingstones. Monkodonja’s destruction raises questions about broader military conflicts in the Adriatic region during this period. Possible causes could include localized warfare or connections to larger-scale disturbances. Research in Monkodonja is also significant in the context of the debate surrounding the emergence of the so-called Castellieri settlements in Istria at the beginning of the 2nd millennium BC. As early as the beginning of the 20th century, it was proposed that a migration of people to the Istrian peninsula brought this new settlement form and other influences, leading to a significant population increase. The appearance of the Castellieri settlement form coincides with a period marked by documented climatic changes and two major natural disasters in the form of volcanic eruptions. Full article

The Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann 1824; Diptera, Tephritidae), is considered one of the most important pests, infesting more than 300 species of fresh fruit and vegetables worldwide. The medfly is an important invasive species, which has spread from the eastern part of sub-Saharan Africa to all of the world’s continents in recent centuries. Currently, the medfly is expanding its geographical range to cooler, temperate areas of the world, including northern areas of Mediterranean countries and continental areas of Central Europe. We collected and analysed all the available information, including in historical records, on the phenology of the medfly in the Balkan Peninsula, to map and understand the path of invasion and spread dynamics on the northern Mediterranean coast and in Central Europe. The medfly was first recorded in the Balkan Peninsula in 1915, in the Aegean area on the island of Aigina, followed by a few records on its presence in the Peloponnese in the early 1930s and throughout the Adriatic coastal area in the 1950s; it was first detected on the Croatian coast in 1947. By 2010, the medfly had been detected along the entire Ionian coast, while the first record of its presence on the Balkan coast of the Black Sea was made in 2005. Since 2000 to date, there has been a significant increase in the frequency of medfly detections in the interior of the Balkan Peninsula, including occasional detections in areas with unfavourable climatic conditions for overwintering, which seems to be favourable for reproduction during the summer and lead to significant infestation of late ripening fruits (late summer and autumn). In the last 20 years, the medfly has spread to more northerly areas (43 to 45 degrees latitude) and has been detected at higher altitudes (>200 to 600 m). Along the Balkan Peninsula, the infestation of fruits from 25 host plant species, from 14 genera and 10 plant families, has been reported. Considering the extremely high invasiveness of the medfly and its wide distribution in several Balkan regions with different climatic conditions, we can assume that it is adapting to new climatic conditions and infesting new host plants. Full article

A 7.4 m long sediment core has been retrieved from the central part of Lake Vrana on the island of Cres to reconstruct the paleoenvironmental conditions. Lake Vrana is the deepest freshwater lake in Croatia, located in the karst region of the eastern Adriatic coast. A dated sediment sequence in Lake Vrana of 4.4 m has spanned the past 16.4 kyr, and it featured a dynamic sediment deposition until the beginning of the Holocene, including strong sediment input and supply to the lake by runoff sediments of dolomitic origin from the catchment in the period 16.4–14.4 cal kyr BP. High organic carbon content, which originates from mixed terrestrial and aquatic origins in the periods 14.4–13.3 cal kyr BP and 12.7–11.7 cal kyr BP, indicates fluctuating lake levels in shallow water environments during the Late Glacial to Holocene transition. The Holocene sequence indicates the development of more stable conditions and continuous sediment deposition, characterized by an increasing trend of siliciclastic sediments delivered into the lake during the early Holocene (11.7–10 cal kyr BP) and dominantly from 8 to 4.4 cal kyr BP, indicating enhanced input and erosion, which coincides with the humid and pluvial period recorded in the central Mediterranean region. It is followed by sediments with high organic carbon content between 4.4 and 1.6 cal kyr BP, which points to higher lake productivity. Calcite sedimentation prevailed between 1.6 to 0.4 cal kyr BP, indicating stable deeper-lake conditions. Predominantly, siliciclastic sediments from 0.4 to 0.1 cal kyr BP pointed to erosion during the Little Ice Age (LIA), with enhanced precipitation and sediment discharge from the catchment. The re-establishment of calcite sedimentation has been observed over the last 100 years. Full article

European maritime states are facing increasing challenges that threaten national security, maritime traffic safety, and environmental protection: increasing maritime traffic, increase in nautical tourism, oil spills, migrant boats, drug smuggling, etc. The Coast Guard is one of the most important government agencies to respond to these challenges. However, the speed of response to incidents depends on the geographical and geostrategic deployment of Coast Guard resources, especially of its homeports. The main objective is to have the Coast Guard’s homeports as close as possible to the national border at sea so that the response time to an incident is as fast as possible. However, there are many other criteria that affect the selection of the maritime location of the Coast Guard homeport. These other criteria (security issues, logistic issues, hydrographic and oceanographic features, and similar) are often in conflict with geographical locations on small remote islands that are close to the state border at sea. Therefore, this research analyzed and proposed the criteria set used to assess the maritime locations that could be potential Coast Guard homeports. A large sample of experts has been interviewed to evaluate the proposed criteria set and to propose criteria weights, thus creating the multi-criteria analysis model for the improvement of the spatial distribution of Coast Guard resources. The proposed model is based on the PROMETHEE method and provides evaluation and ranking of the maritime locations in order to help the Government prioritize the development of the maritime locations into the homeports for the deployment of Coast Guard resources. The case study of the eastern Adriatic Sea with real-world maritime locations and data was used to test the proposed model. The results have shown that, with proper strategic planning of the deployment of Coast Guard resources, the sustainability, safety, and security of the sea and the coast can be increased. Full article

Considering the role of phytoplankton in the functioning and health of marine systems, it is important to characterize its responses to a changing environment. The central Adriatic Sea, as a generally oligotrophic area, is a suitable environment to distinguish between regular fluctuations in phytoplankton and those caused by anthropogenic or climatic influences. This study provides a long-term perspective of phytoplankton assemblage in the central eastern Adriatic Sea, with 14 years of continuous time series data collected at two coastal and two offshore stations. The predominant phytoplankton groups were diatoms and phytoflagellates, but their proportion varied depending on the vicinity of the coast, as evidenced also by the distribution of chlorophyll a. In the coastal environment, the phytoplankton biomass was substantially higher, with a higher proportion of microphytoplankton, while small phytoplankton accounted for the majority of biomass in the offshore area. In addition, a decreasing trend in diatom abundance was observed in the coastal waters, while such trend was not so evident in the offshore area. Using a neural gas algorithm, five clusters were defined based on the contribution of the major groups. The observed increase in diversity, especially in dinoflagellates, which outnumber diatom taxa, could be a possible adaptation of dinoflagellates to the increased natural solar radiation in summer and the increased sea surface temperature. Full article

The relatively new sea level satellite altimetry and secular coastal tide gauge data made the reconstruction of sea levels on regional and global scales possible about one century back. Due to better estimations of the Earth’s crustal, glacial, tectonic, and other possible motion biases in tide gauge data, some additional improvements can be expected in sea level reconstructions, analysis, and predictions. A more detailed review of published sea level-related results was conducted for the Eastern Adriatic coast, including the operation of the tide gauge network and data processing, crustal movement estimations, and the establishment of a new reference height system in Croatia, based on five tide gauge sea level data. It was shown that sea level variation and trend-related indicators are spatially homogeneous, especially on a sub-Adriatic scale. The regional Adriatic Sea mean sea level rise rate of +2.6 mm/year for the satellite altimetry era (1993–2019) is less than the global mean sea level (GMSL) rise rate of +3.3 mm/year for the period of 1993–2022. Several empirical methods for GMSL projections and expected IPCC (Intergovernmental Panel on Climate Change) assessments until the end of the 21st century are considered. Full article

Marine diatoms of the genus Pseudo-nitzschia are widespread and occur in various environments. About half of the species described today have been shown to be toxic, producing the potent neurotoxin, domoic acid. The Pseudo-nitzschia species are a common component of the Adriatic phytoplankton community and are occasionally predominant. In the present study, the composition of the Pseudo-nitzschia species was studied in four distinct aquaculture areas from February 2022 to February 2023. These are the first results of a comprehensive study of Pseudo-nitzschia diversity combining morphological and molecular analyses. The integrated approach resulted in the confirmation of Pseudo-nitzschia brasiliana, Pseudo-nitzschia hasleana, Pseudo-nitzschia galaxiae, and Pseudo-nitzschia linea. The species, P. galaxiae, was the most frequently occurring, P. linea was found in all investigated areas, while P. hasleana and P. brasiliana were rare, and their distribution was limited mainly to Kaštela Bay. The findings of P. brasiliana and P. hasleana represent the first confirmation for the Adriatic Sea, while P. galaxiae and P. linea have not been previously reported along the eastern Adriatic coast. Full article

The impact of recreational fishing on fish stocks was neglected for many years as it was considered minor and insignificant. Despite the increasing assessment of the impact of recreational fishing, little effort is made to effectively and systematically collect catch and effort data from recreational fishing and integrate them into official fishery statistics. The aim of this study is to provide the first empirical investigation to quantify the impact of spearfishing on coastal fish communities in the eastern Adriatic. In Croatia, continuous monitoring of spearfishing competitions started in 2005, but, in 2012, the rules for the competitions were changed, and the species and quantities per species were restricted. For the purpose of this analysis, only data collected during the seven-year period from 2005 to 2011 were used, which included a total of 46 competitions in which spearfishers fished without any limitations, as later data were not comparable. These data can provide a robust estimation of the impact of spearfishing on coastal communities. Instead of a general approach, future studies should adopt a species-specific approach. Compared to the results on the impacts of other fishing methods, the obtained results are useful for researchers, managers, and also policy makers to sustainably manage coastal ecosystems and the associated ecosystems services. Full article

The shrimp Penaeus aztecus, native to the western Atlantic, was first reported in the eastern Mediterranean Sea in 2010. New records, from different Mediterranean localities, multiplied in the following years. The accurate search of the literature on non-indigenous species discovered it was misidentified more than once as another alien shrimp, P. semisulcatus, native to the Indo-Pacific region, with the result that its earlier presence in the Black Sea went unnoticed. Morphological characteristics allowing the identification of these two species, the autochthonous P. kerathurus and two other alien Penaeus species present in the Mediterranean, are reprised. The present distribution of P. aztecus based on literature records and surveys carried out in the northern and central Adriatic between 2016 and 2021 is mapped. The unintentional transport of larvae carried in ballast water by transoceanic vessels departing from the U.S. East Coast is suggested as the most probable introduction pathway. The significance of the correct identification of non-indigenous species, a “Descriptor” adopted in the Marine Strategy Framework Directive for determining the good environmental status of marine waters in the European States, is emphasized. Full article

The analysis of plants featured in Baroque artworks on the eastern Adriatic coast has not previously been the subject of an in-depth study. The study of plant iconography in Baroque sacred artworks, which are mostly paintings, was carried out in eight churches and monasteries on the Pelješac peninsula in southern Croatia. Taxonomic interpretation of the painted flora on 15 artworks led to the identification of 23 different plant taxa (species or genera) belonging to 17 families. One additional plant was identified only by family taxonomic rank. The number of plants was relatively high, and most species were considered non-native (71%, “exotic” flora) phanerophytes. In terms of geographic origin, the Palaearctic region (Eurasia) and the American continent were identified as the main areas of plant origin. Lilium candidum, Acanthus mollis, and Chrysanthemum cf. morifolium, were the most common species. We think that the plants were selected for decorative and aesthetic reasons, as well as for their symbolic significance. Full article

Croatia’s coast located on the eastern Adriatic is rich with small gravel beaches with limited fetch. This leads to a specific low-energetic wave climate compared to most other beaches, while their gravel composition makes them unique. Most management of these beaches is performed without understanding the sediment transport occurring on the beaches. XBeach-Gravel is a numerical model capable of simulating bed-level change on gravel beaches, but lacks validation in the case of low significant wave height (under 2.5 m) and low peak periods (under 6 s), conditions that are present on the eastern Adriatic. Based on measurements performed in both laboratory conditions in a water canal in Hannover and actual storm wave conditions on Ploče beach, calibration of the model is performed. Model results are compared between laboratory conditions and field conditions for comparable wave conditions. XBeach-Gravel can simulate low-energetic events resulting in berm formation and berm buildup with a high Brier skill score if calibrated. Simulation of laboratory conditions requires high transport coefficient values and shows more sediment transport than similar wave conditions in the field. Calibration for field conditions is dependent on geodetic survey data capable of isolating wave events with dominant cross-shore transport, but once calibrated, XBeach-Gravel can achieve good to excellent Brier skill score values in simulating sediment change in low-energetic wave conditions on the eastern Adriatic. Full article