Romanian Black Sea Coast Research Articles

An Integrative Approach to Assess and Map Zostera noltei Meadows Along the Romanian Black Sea Coast

Seagrass meadows, including those formed by Zostera noltei, play a crucial role in marine ecosystem health by providing habitat stability and coastal protection. In the Romanian Black Sea, Z. noltei meadows are critically endangered due to pressures from eutrophication, habitat loss, and climate change. This study presents a comprehensive baseline assessment of Z. noltei meadows near Mangalia, Romania, utilizing in situ field methods and UAV mapping conducted in the spring and summer of 2023. Seven meadow sites (Z1–Z7) were identified, with notable variability in density, shoot counts, and coverage across sites. Site Z1 exhibited the highest density (1223 shoots/m−2) and Z5 and Z7 the longest leaves (an average of 60 cm), reflecting possible environmental influences. Statistical analyses revealed significant inter-site differences in shoot density and leaf length, with density emerging as a primary differentiator. Ex situ analyses of epiphyte load indicated a median, balanced epiphyte load. This baseline dataset supported the selection of Z1 as a reference donor site for seagrass relocation activities along the Romanian coast in 2023. By providing critical insights into Z. noltei structure and health, this study supports future conservation efforts and evidence-based management of these vulnerable coastal habitats.

Ulva species from the Romanian Black Sea Coast – between green blooms and nature’s contribution to people

Ulva species have a worldwide distribution and remarkable ability to develop under various conditions, being considered an important natural resource that is under-exploited along the Romanian Black Sea coast. These green algae, involved in green tides observed worldwide, have also a remarkable potential as prolific sources of bioactive compounds with potential health benefits and a wide range of applications in food, feed, pharmaceutical, nutraceutical, cosmetic, or biofuel industries. The study aims to analyze the quantitative variability of Ulva spp. during 2019 - 2023, in order to highlight the areas with algal agglomerations. These are also areas where potential algal deposits can develop during summer season. This fresh biomass can be selectively collected and valorized, thus supporting the circular economy. The sampling method was the classic one (square method/20x20 cm) from 14 stations along Pescarie towards Vama Veche, at depths between 0 to 3 m deep. Among all Ulva spp., Ulva rigida and Ulva intestinalis quantitatively distinguished during the study period, being also the main components of algal deposits. The highest mean wet biomasses were recorded in the southern part, as follows: U. rigida – a maximum value of 2200 g/m2 at 2 Mai; U. intestinalis – max. value of 700 g/m2 at Eforie South. Furthermore, a review of species’ main bioactive compounds, emphasizing their potential health benefits, will also be provided.

Morphological characteristics of the species Gaidropsarus Mediterraneus (Linnaeus, 1758) population from the Romanian Black Sea coast in the year 2023

The aim of this study is to provide an overview of the Gaidropsarus mediterraneus (Linnaeus, 1758) species growth pattern from the Romanian Black Sea Coast, in the year 2023. This has been accomplished by studying the length-weight relationship, an important parameter, which helps to know the growth pattern of fish populations, Fulton’s condition factor (kc) (useful index for monitoring feeding intensity) from 180 shore rockling individuals caught by pots. Average lengths and weights were 24.4 ± 2.6 cm and 101.46 ± 38.11 g, respectively, the minimum and maximum values were 18.3 and 33.8 cm, 36 and 319 g in weight. The value of exponent b in the equation is 3.197, indicating that the increasing weight is allometrically positive and mean value of the Fulton was 0.68 ± 0.08, with the minimum and maximum values of 0.47 to 0.90. The obtained results can have useful effects on the stock management of this fish species.

Evolution of the beach artificial nourishments in the Tomis North sector, a short term analysis (2013-2024)

The Romanian coastline is part of the western coast of the Black Sea, extending for about 245 km, morphologically divided into two units: the northern unit, from Musura Bay to Cape Midia, with deltaic and lagoon origin, and the southern unit, from Cape Midia to Vama Veche, characterised by well-developed cliffs and wide beaches. This last coastal sector includes both accumulating coastlines (beaches) and anthropogenic features (ports and breakwaters). Constanta, the largest and most important city in Dobrogea, claims a rich history and a variety of tourist attractions, with its beaches stretching some 6 km along the coast from Tomis Marina to the entrance of Mamaia Resort. This study analyses the recent changes observed at a popular tourist beach known as Reyna Beach, located near Mamaia Resort, following the nourishment works carried out in the framework of the "Protection and Rehabilitation of the Southern Part of the Romanian Black Sea Coast" project. The project involved extensive hydrogeographic works, including the rehabilitation of piers, the construction of submerged breakwaters and beach nourishment. This paper aims to analyse the evolution of the coastal area from a geographical perspective, including geological and geomorphological characteristics, using various data sources such as satellite images, field measurements and previous maps associated to grounding studies.

Current status of zoobenthic fauna associated with macroalgae fields from the southern Romanian Black Sea coast

The European environmental policies related to marine water management require a periodic environmental status assessment. The Marine Strategy Framework Directive 2008/56/EC clearly specifies that assessment must take into consideration benthic habitat types, including their associated biological communities. The aim of this study is to present the results of the ecological analysis of the zoobenthic communities associated with benthic habitats with macrophytic substrate and to provide new data regarding the qualitative and quantitative structure of macroinvertebrates that populate these habitats type. The broad habitats type Infralittoral rock and biogenic reef and Infralittoral sands were investigated. The analyzed data covers the summer season, 2023 based on the processing of 13 samples collected from Navodari to 2 Mai – Vama Veche, on depths ranging between 1m to 3 m. A total of 80 macrozoobenthic species were found in all macrophytic assemblages, the Polychaeta, Crustacean and Gastropod were the dominant groups, especially Perinereis cultrifera, Platynereis dumerilii, Ampithoe ramondi, Stenothoe monoculoides, Rissoa splendida, Tricolia pullus registering a large number of individuals. For data interpretation a synecological analysis was performed allowing the identification of the species with the most significant contribution in the ecosystem in terms of function, energy exchanges with the environment, the characteristic species of a biotope or those that have an accidental presence in the studied area.

Recent Trends in Air Pollution in the Most Important City of The Romanian Black Sea Coast

Air pollution is one of the greatest environmental issues of contemporary society, affecting virtually all major cities worldwide, including those in Romania. Consequently, evaluating the dynamics of pollution conditions in urban environments is essential for designing control measures and adaptation strategies to this environmental disruption. This paper aims to analyze the recent dynamics of pollution and air quality in Constanta, the largest city on the Romanian coastline and one of the most important cities along the entire Black Sea coast. The investigations were based on the official concentrations of major atmospheric pollutants recorded at air quality monitoring stations located within or near Constanta. The dynamics of pollutant concentrations were explored at annual and seasonal levels, and the results showed a mixed picture of changes in the atmospheric pollutant concentrations, in recent years. Essentially, the findings highlighted both increases and decreases in air pollution conditions, emphasizing the need for constant air quality monitoring and controlling throughout Constanta city.

Heavy Metal Concentrations in Wild Mussels Mytilus galloprovincialis (Lamarck, 1819) during 2001–2023 and Potential Risks for Consumers: A Study on the Romanian Black Sea Coast

Heavy Metal Concentrations in Wild Mussels Mytilus galloprovincialis (Lamarck, 1819) during 2001–2023 and Potential Risks for Consumers: A Study on the Romanian Black Sea Coast

BIOCHEMICAL CHARACTERIZATION AND EXPLOITATION POSSIBILITIES OF Gongolaria Barbata (Stackhouse) Kuntze 1891 FROM THE ROMANIAN BLACK SEA COAST

Black Sea macroalgae are a marine resource with many benefits. Gongolaria barbata (Stackhouse) Kuntze 1891 (formerly known as Cystoseira barbata (Stackhouse) C. Agardh, 1820) is a brown macroalga with an essential role in biodiversity and in the marine ecosystem functioning, considered an ecologically valuable species at the Romanian Black Sea coast. Samples were collected during 2002 and 2023 years (August-September) from 6 stations of the Romanian Black Sea coast in order to characterize biochemically and highlight the presence of some biologically active compounds with therapeutic, pharmaceutical and cosmetic interest. Biochemical composition (dry matter, moisture, ash, organic matter, crude proteins, crude lipids, carbohydrates, chlorophyll a, chlorophyll b, carotenoids) and dietary fiber (CF, ADF, NDF, NDF, NDS, ADL) were evaluated in this study. The obtained results indicate some differences between the two years and these are influenced by the environmental conditions and physiological state of macroalgae. Although present on the Romanian coast, Gongolaria barbata has not been intensively studied in terms of its valorization potential, but it has recently attracted attention due to its biochemical properties that lead to some possibilities of use for economic purposes. The existence of valuable biochemical compounds in the composition of this brown macroalga qualifies it in the marine resources category of interest with biotechnological applications.

FOOD AVAILABILITY ON INFLUENCE MUSSEL Mytilus galloprovincialis (Lamarck, 1819) ON PHYSIOLOGICAL AND BIOCHEMICAL STATUS

Phytoplankton, as the primary food source for suspension-feeding bivalves, can significantly impact the growth and survival of bivalves. To investigate the influence of food availability on the condition index and biochemical composition of mussels Mytilus galloprovincialis from the Romanian Black Sea coast, phytoplankton and mussels samples were collected from four sites between November 2017 and November 2018. The phytoplankton quality and quantity varied across locations and seasons. The ports had the highest diversity and abundance of phytoplankton, while the area with low trophic conditions had the lowest. The most dominant phytoplankton groups observed were diatoms and dinoflagellates. The condition index values were higher in sites with greater food availability, reaching the peak in spring. The lipid and carbohydrate content peaked in spring when the food availability was high. The protein content was higher in winter and autumn. Condition index was positively correlated with phytoplankton abundance and biomass (p 0.05). Several significant correlations were found between the biological parameters of mussels, such as proteins, lipids, carbohydrates, tissue dry weight, moisture, ash free dry weight, and ash. In conclusion, the results indicated that higher food availability and increasing seawater temperatures led to greater condition index and reserve accumulation, primarily in the form of proteins, carbohydrates, and lipids, providing mussels with enough energy to withstand stressful conditions.

Long term succession of engineering species Gongolaria barbata (Stackhouse) Kuntze (Fucales: Ochrophyta) along the Romanian Black Sea coast

Background and purpose: Cystoseira sensu lato are of great interest due to their primary role in maintaining high biodiversity and the functioning of rocky habitats, and as provider of crucial ecosystem services. Conspicuous historical declines have been reported in many regions, Romanian Black Sea coast included. Gongolaria barbata (Stackhouse) Kuntze (Fucales: Ochrophyta) is the only remaining representative of Cystoseira s. l. along the Romanian coast and currently the most important habitat-forming species, with extended to patchy canopies in the southern rocky coasts. To better understand the status of such ecological important species, we analyse and compare the succession of Gongolaria infralittoral populations during reference (60s), decline (70s) and more recent period (2009 – 2022), based on an extensive literature review (historical quantitative data) and recent information from annual monitoring program. Material and methods: Quadrats (20 × 20 cm) were used for sampling both in the past and present, with a total number of 144 samples collected between 2009 – 2022. Both historical and recent data were statistically analysed using non – parametric tests due to the absence in normality and homogeneity of data sets. Results: Following sea ice from 1972 and violent storms as the main drivers of local Gongolaria decline, out of the thirteen known development areas from the reference period, nowadays only five are left. However, recent wet biomass and density values are appropriate to those of the reference period (1962 – 1971) and much higher compared to the maximum decline period (1972 – 1979). Conclusions: G. barbata has been in a fragile balance along the Romanian coast in the last decade, highly sensitive in front of increasingly anthropogenic activities.

Reducing greenhouse gas emissions in Romanian agriculture using renewable energy sources

This paper aims to demonstrate the feasibility, regarding environmental and economical point of view, of a local tomato farm powered by an offshore wind farm for Romanian Black Sea coast, where there are no such projects implemented and just one is foreseen so far. In this regard, both the agricultural farm and the offshore wind farm were dimensioned and using a new methodology proposed in the year 2023 by the World Bank, an environmental analysis of the project was made with estimating the positive effects that occur in the GHG emissions at the implementation of this project. The relationship between energy inputs and farm yields is analysed for two cycles of tomato crops and a comparative evaluation is conducted to emphasise the favourable influence that the implementation of the proposed solution would exert on the carbon footprint of Romania's agriculture sector. The two scenarios considered are Scenario 1 - S1 with tomato farm in the Schitu area (in greenhouses powered by an offshore wind farm, Cycle 1 and in open field, Cycle 2) and Scenario 2 - S2 when the tomatoes are imported from proximate regions. For both cycles, the energy ratio and energy productivity values were calculated, obtaining 0.11 and 0.13 for cycle C1, and 0.67 and 0.84 for cycle C2, respectively. The benefits of the proposed solution presented in S1 are represented by a) enhancing agricultural production by exploiting a renewable energy source with a yearly production of 45.07 GWh; b) reducing the transport distance of tomatoes by 324,057 km; c) promoting the local economy by employing an average of 124 people; d) improving the carbon footprint of Romania's agricultural sector with a reduction of CO2e per year of 43.13%.

Qualitative Model of the Causal Interactions between Phytoplankton, Zooplankton, and Environmental Factors in the Romanian Black Sea

In order to analyze how environmental factors affect planktonic organisms along the Romanian Black Sea coast, this study created semi-quantitative models of the causal relationships between phytoplankton, zooplankton, and physicochemical parameters by utilizing user-friendly modeling tools. Eleven years of time-series data (March–September 2008–2018) were used to investigate the relationships between phytoplankton, zooplankton, and environmental factors (such as temperature, salinity, and nutrients). Variables such as marine reporting units and phytoplankton species and classes were used to identify developmental patterns, utilizing the Mental Modeler platform to consider interactions between the physicochemical parameters and phytoplankton, phytoplankton and zooplankton, and zooplankton and physicochemical parameters. Although the increase in the overall number of elements and linkages was uncertain in waters with variable salinity compared to marine ones, the semi-quantitative models created for the three marine reporting units along the Romanian Black Sea coast were comparable in terms of complexity. Across the typical and examined types of phytoplankton proliferation (normal, abundant, and blooms), the number of components and connections in the case of phytoplankton blooms substantially decreased as species- and growth-promoting variables increased.

Modeling Dynamic Processes in the Black Sea Pelagic Habitat—Causal Connections between Abiotic and Biotic Factors in Two Climate Change Scenarios

The paper contributes to the Sustainable Development Goals (SDGs) targeting Life Below Water by introducing user-friendly modeling approaches. It delves into the impact of abiotic factors on the first two trophic levels within the marine ecosystem, both naturally and due to human influence. Specifically, the study examines the connections between environmental parameters (e.g., temperature, salinity, nutrients) and plankton along the Romanian Black Sea coast during the warm season over a decade. The research develops models to forecast zooplankton proliferation using machine learning (ML) algorithms and gathered data. Water temperature significantly affects copepods and “other groups” of zooplankton densities during the warm season. Conversely, no discernible impact is observed on dinoflagellate Noctiluca scintillans blooms. Salinity fluctuations notably influence typical phytoplankton proliferation, with phosphate concentrations primarily driving widespread blooms. The study explores two scenarios for forecasting zooplankton growth: Business as Usual, predicting modest increases in temperature, salinity, and constant nutrient levels, and the Mild scenario, projecting substantial temperature and salinity increases alongside significant nutrient decrease by 2042. The findings underscore high densities of Noctiluca scintillans under both scenarios, particularly pronounced in the second scenario, surpassing the first by around 70%. These findings, indicative of a eutrophic ecosystem, underscore the potential implications of altered abiotic factors on ecosystem health, aligning with SDGs focused on Life Below Water.

Valorization of Mussel Waste from the Romanian Black Sea Coast

In this study the shells and byssus of Mytilus galloprovincialis, the mussels from the Romanian Black Sea coast were studied through biotechnological techniques, to determine if they can be highly economically valorized. The shells were processed in order to obtain calcium carbonate (CaCO3) and subsequently calcium chloride (CaCl2), natural compounds with multiple practical applications in the pharmaceutical industry, medicine, agriculture, animal husbandry, environment, etc. Calcium carbonate was obtained from mussel shells with a yield of 95.31%, and calcium chloride was obtained with a yield of 73.80% from CaCO3, percentages that support the efficiency of the biotechnological processes for obtaining these products. The byssus collected from M. galloprovincialis was processed using a pepsin-aided etraction method, which allowed obtaining collagen with a yield of 27,56%. Mussel byssus is a waste and may provide an alternative to other types of eisting collagen from animal sources with different applications in pharmaceutical industry, tissue engineering, medical field, food industry, cosmetics.

Trends in the Evolution of the Average Length of Stay in Tourist Destinations on the Romanian Black Sea Coast

Trends in the Evolution of the Average Length of Stay in Tourist Destinations on the Romanian Black Sea Coast

Diversity and dynamics of tintinnids communities from Romanian Black Sea, in 2021

Tintinnids are tiny ciliates from microzooplankton that are very important due to their implication in the microbial food web and for the fact that in the last two decades a considerable number of non-indigenous species have entered and acclimatized in the Black Sea basin. The paper presents the species diversity and dynamic of microzooplanktonic tintinnids’ abundance as a result of two cruises carried out in May-June and August-September 2021, along the Romanian Black Sea coast. We identified 23 tintinnid species in total, with a higher diversity in the surface layer compared to those of depth. The species Eutintinnus sp. and Salpingella decurtata were found eclusively in the 10 m layer. Tintinnopsis cylindrica represented 74% of the mean biomass of tintinnid’s community from May-June, the best quantitative representation recorded in the Romanian coast's northern sector. Amphorellopsis acuta represented 91% of the mean biomass of tintinnid’s community in August-September. The biotic component was also correlated with temperature and salinity to give more information regarding spatial and temporal variations from one area to the other. The findings contribute to the knowledge of microzooplankton communities in the Romanian Black Sea region. The data on species composition, abundance distribution, and environmental correlations enhance our understanding of the ecological dynamics and potential ecological implications of tintinnid communities. This study brings valuable information to the understanding of the microzooplankton component in the Black Sea ecosystem.

The Variability of the Beach Morphology and the Evolution of the Shoreline in the Strongly Anthropized Sector of Eforie North, the Romanian Coast of the Black Sea

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).

Oceanographic research for a future tourist marina on the Romanian Black Sea coast

The aim of this paper is to analyze the importance of oceanographic research in the development of a future touristic marina on the Black Sea coast. Oceanographic research plays a crucial role in understanding the marine ecosystem, assessing the impact of human activities, and developing appropriate conservation and management strategies for sustainable tourism. Key areas of research include water quality assessment, biodiversity study, monitoring the impact of tourist activities on marine habitats, studying climate change, and developing adaption and mitigation strategies. By integrating oceanographic research into the planning and development process, stakeholders can ensure responsible and sustainable tourism that protects the marine environment and its biodiversity.

Epidemiology of Turbot (Scophthalmus maeoticus) Bacterial Contamination, a Fishery Limiting Factor on the Romanian Black Sea

The aim of this research was to evaluate the health status of the Scophthalmus maeoticus (Pallas, 1814) population from the Romanian marine area in 2016–2019, by identifying and investigating information about bacterial and constitutional diseases, establishing the influence of these bacterioses on the researched populations, and highlighting the main biological disorders (reproduction, growth, and feeding) that manifested in the analyzed fish. The bacterial diseases reported in S. maeoticus (Pallas, 1814) populations were caused by pathogens from the genera Vibrio, Aeromonas, and Pseudomonas. Numerous skin diseases, especially various types of “wounds”, lesions of bony tubercles, and tissue lesions may be the subsequent cause of neoplasms, as a result of fishing gear manipulations. The appearance of significant changes in the prevalence of neoplasia on the Romanian Black Sea coast can be considered an indicator of chronic stress (anthropogenic impact), rather than acute (environmental impact), and we suggest that the species could be used as a biological indicator of changes that may occur in the habitat in which it lives. In terms of future research directions, a combined analysis of the population structure, morphology and diseases determined in S. maeoticus populations, with a structural analysis of the habitat and bacteria contamination degree would be useful; this monitoring should be carried out regularly, to reveal changes in the Black Sea ecosystem, and to propose possible recommendations and protective measures.

Lysosomal Membrane Stability of Mussel (Mytilus galloprovincialis Lamarck, 1819) as a Biomarker of Cellular Stress for Environmental Contamination.

The lysosomal membrane stability (LMS) of hemocytes in wild mussels (Mytilus galloprovincialis) as a biomarker of cellular stress for chemical pollution was tested by neutral red retention time (NRRT) assays. To assess the environmental contamination in the study area, seawater quality and pollutant bioaccumulation throughout the soft tissue of mussels were investigated. The samples were collected in July 2022 at four sites on the Romanian Black Sea coast considered to be differently affected by contamination. To support the suitability of LMS as a biomarker of contaminant-induced stress, the contaminant body burdens of the mussels were compared with the NRRT values. The results showed a significantly reduced NRRT in all investigated locations, particularly in port areas (mean retention time between 11 and 14 min). The elevated bioaccumulation of organochlorinated pesticides (OCPs) and polychlorinated biphenyls (PCBs) and low NRRTs were observed at the most contaminated sites (i.e., ports). The low lysosomal stability reflected stress and damage in the hemocytes of mussels and could be related to the body burdens of contaminants. LMS is an effective indicator of health status in mussels and could be considered a sensitive biomarker of cellular stress induced by contaminant exposure.