This study provides a comprehensive six-year assessment (2018–2023) of heavy metal contamination in the Romanian Black Sea sector, integrating data from seawater, surface sediments, and benthic mollusks. Sampling was conducted across a broad spatial gradient, including transitional, coastal, shelf, and offshore waters beyond 200 m depth. Concentrations of six potentially toxic metals, including cadmium (Cd), lead (Pb), nickel (Ni), chromium (Cr), copper (Cu), and cobalt (Co), were measured to evaluate regional variability, potential sources, and ecological implications. Results indicate some exceedances of regulatory thresholds for Cd and Pb in transitional and coastal waters, associated with Danube River input and coastal pressures. Seabed substrate analysis revealed widespread enrichment in Ni, moderate levels of Cr, and sporadic Cd elevation in Danube-influenced areas, along with localized hotspots of Cu and Pb near port and industrial zones. Biological uptake patterns in mollusks (bivalves Mytilus galloprovincialis and Anadara inequivalvis and gastropod Rapana venosa) highlighted Cd among key metals of concern, with elevated Bioconcentration Factor (BCF) and Biota–Sediment Accumulation Factor (BAF). Offshore waters generally exhibited lower pollution levels. However, isolated exceedances, such as Cr outliers recorded in 2022, suggest that deep-sea inputs from atmospheric or maritime sources may be both episodic in nature and underrecognized due to limited monitoring coverage. The combined use of water, sediment, and biota data emphasize the strength of multi-matrix approaches in marine pollution evaluation, revealing persistent nearshore pressures and less predictable offshore anomalies. These findings contribute to a more complete understanding of heavy metal distribution in the northwestern Black Sea and provide a scientific basis for improving long-term environmental monitoring and risk management strategies in the region.

The Eforie Nord sector (between the southern pier of Agigea - Constanta port and the tourist port of Belona), is characterized, from a geomorphological point of view by the presence of high cliffs and narrow beaches. In the mentioned sector, a series of coastal protection works were carried out in several stages, respectively: between 1956 and 1960, 6 groins were placed to etend the perimeter beach; with the epansion of Constanța port, new coastal protection measures were imposed (1981-1986), determined by the erosion processes, made concrete by the eecution of permeable submerged longitudinal dikes in addition to the transversal ones. On long term, the measurements of shore morphological parameters highlighted that the southern sector of the Romanian Black Sea coast is subject to an erosion process, due to the action of both natural and anthropogenic factors, each generating effects with different intensity, depending on local conditions. Within the project “Protection and Rehabilitation of the Southern Part of the Romanian Black Sea Coast, Phase 1” in 2014-2015 period, in the mentioned sector, etended hydrographical works were carried out, including the rehabilitation of dikes, the construction of submerged dikes and beach nourishment. The monitoring of the shore behavior at regular intervals (annual/seasonal) which is essential for an adequate management of the coastal area, highlights both cyclical/seasonal morphological changes (rapid erosion as a result of storms in the cold season and the reconstruction of the beach during summer) and progressive/multiannual changes. The monitoring of morpho dynamic changes at shore level includes the positioning of the shoreline and beach profiles in 6 locations using GPS equipment (geodetic and GIS class). The resulting spatial data were processed and included in the SANDS management system that allows comparative analysis at different time scales. The maps representations were made in the ArcGIS 10.8 system. The data analysis revealed seasonal changes of the shore morphology, both in the longitudinal profile (shoreline) and transversally (beach profiles).

"The paper presents the results of seasonal marine litter surveys carried out during the period 2018 – 2019 along the Romanian littoral of the Black Sea on 3 sandy beaches differing in their touristic exploitation and urbanisation. The assessment of abundance and composition of macrolitter (> 2.5 cm) and microplastics (1-5 mm) followed the monitoring methodology described in the EU MSFD TG10 guidance (Galgani et al., 2013). Out of the fifty-five litter types mostly monitored, cigarettes buts and plastic/polystyrene pieces (2.5 cm - 50 cm) made up the highest contribution with more than 50% in all years. The mean abundance of total microplastics ranged from 4 and 272 particles/m2 among sites; the microplastics were mostly expanded polystyrene (EPS), fragments and films. The microplastic abundance in touristic beaches of Mamaia resort (Marina Regia and Malibu) was between 2 and 30 times higher than in protected wild areas (Vadu). Overall, the different types and quantities of marine litter found during our study were related to differences in human activities set up in all three locations in touristic and post-touristic season 2018 and 2019. The highest macrolitter and microplastic concentrations were recorded in the southern area of Mamaia summer resort (Malibu beach) indicating that beside the level of coastal infrastructure development, the seasonal tourists and local population density are important factors affecting marine litter pollution level on the Romanian beaches. Key-Words: marine litter, macrolitter, microplastics, beach sediment, Black Sea "

Coastal erosion poses a significant risk to the Romanian Black Sea coast, a region characterized by the interaction of natural geomorphological processes and anthropogenic pressures. The research focuses on developing a tool to quantify the cumulative impact of hydro-geo-morphological factors and to assess the vulnerability of the coastal zone to these influences. The approach involves adapting the Coastal Vulnerability Index (CVI)—previously applied in various methodologies—to the specific characteristics of this semi-enclosed basin, which included the exclusion of the tidal range variable due to the Black Sea’s negligible tidal amplitude. The selection of key variables, including coastal geology and geomorphology, shoreline change rates, coastal slope, sea level, and wave regime, was conducted with consideration for the specific characteristics of the Romanian coastal zone. By classifying these variables on a semi-quantitative scale and integrating them into a CVI, the study identifies and maps areas of high vulnerability. The analysis, based on a 1 × 1 km grid resolution, identified sectors of very high vulnerability in the northern Danube Delta unit, particularly along the coastlines of South Sulina–Câşla Vădanei, Sahalin, and Periboina-Edighiol-Vadu. These findings are validated through a comparison with long-term, multidecadal shoreline evolution data, confirming the model’s predictive accuracy. While the 1 × 1 km grid is effective for a macro-scale assessment, the study highlights the need for a finer resolution (e.g., 100 × 100 m) for detailed analysis in the southern region, due to localized geodynamic conditions and the significant influence of coastal infrastructure.

Plastic and marine litter is one of the current growing issues worldwide, affecting the unique Black Sea ecosystem as well. Litter is yearly monitored for assessing ecological status across the Romanian beaches. We tested aerial drone-inspection or UAV method versus visual census for efficiency of litter monitoring on two Black Sea beaches, located in the Danube Delta area. The detection probability varied between size-category of items, with 71 – 100% accuracy of visual screening of drone images. Our pilot study showed the successful combination of the traditional visual census method with the new emerging UAV techniques for marine litter monitoring in the selected areas. To the best of our knowledge, this is the first study evaluating the UAV method for fast-screening of not-easily accessible sites at the Romanian coast of the Black Sea.

"The paper analyses the changes in the beach sector of Mamaia resort from a geomorphological and sedimentological point of view in the context of coastal protection works carried out in 2014-2015 and 2021 (measures to reduce wave energy, beach protection with structures to stabilize the sand and beach nourishment). The Mamaia sector, with a length of about 12 km, is geomorphologically constituted mainly by sandy barrier of Lake Siutghiol representing a transition unit between the northern unit (deltaic and lagoon shore) and the southern unit (small pocket rocks-beaches in front, separated by small coastal sandbars). From an economic point of view, the sector is important for coastal tourism both in terms of the number of tourists and the existing of infrastructure generating significant revenues. Since the 1950s, the sector has been severely affected by the construction of the dikes of the Midia Port in the north, which have affected the longitudinal transport of sediments and accentuated the erosion of the submerged and backshore beach. To counteract the effects of erosion, a longitudinal and transversal coastal protection system was built between 1960 and 1990, which proved to be ineffective in the long term. The data collected in the field (topographic profiles of the backshore, shoreline, sediment samples) before and after the recent coastal protection works were processed using a dedicated software (ArcGIS 10.x and Gradistat v8) and represented in the form of maps and graphics. The spatial analysis highlighted the modification of the coastal system components, the trends of the beach evolution in longitudinal and transversal profile and the changes in the structure and distribution of sediments determined by the impact of the coastal protection works."