Helena Ukić Boljat

Sanitary wastewater discharges from recreational vessels are a difficult-to-quantify source of pressure in coastal anchorages because discharge events are intermittent, mobile and strongly dependent on user behaviour. We developed an integrated screening framework that jointly interprets environmental state (faecal indicator bacteria; FIB), pressure proxies (instantaneous vessel abundance and size structure), and behavioural/infrastructure context (a survey of wastewater systems and disposal practices). Ninety-six seawater samples from three stations were analysed for Escherichia coli and intestinal enterococci during 32 morning/afternoon campaigns. All individual samples were below the Croatian single-sample thresholds for excellent sea-bathing quality (E. coli < 100 and intestinal enterococci < 60 CFU/100 mL), although intestinal enterococci and E. coli were detected in 32% and 15% of the samples, respectively. The microbiological signal was descriptively stronger in the morning even though vessel abundance was substantially higher in the afternoon (121 vs. 266 vessels), and the highest FIB concentrations occurred at the southern low-local-pressure reference station, which had the fewest observed vessels (44). These differences were not statistically significant. Survey data showed that 82% of the respondents used vessels equipped with black-water-holding tanks, while marina pump-out facilities were used infrequently and disposal during navigation was reported more often. The integration therefore lies in triangulating non-equivalent lines of evidence: microbiological signals, observed boating pressure, and user/infrastructure conditions. This approach is intended for first-line screening and targeted monitoring, not for direct source attribution.

As maritime transport continues to grow, the volume and complexity of waste generated by ships, such as garbage, sewage, and oily residues, requires the establishment of effective, accessible and well-regulated collection systems in ports. Ensuring effective waste management remains a major challenge across the European Union, as differences in national implementation and charging systems continue to undermine the sustainability of port reception facilities. Directive (EU) 2019/883 on port reception facilities (PRF Directive) was introduced to harmonise regulatory standards, ensure adequate infrastructure, and remove barriers to proper waste management. This paper analyses the transposition and implementation of the PRF Directive in selected EU countries, focusing on the differences in cost recovery systems (CRS) applied in ports. A comparative analysis of charging models and waste management plans for ports is carried out, including an in-depth study of the leading European ports with the highest reported waste volumes. A nine-criteria evaluation framework was developed through a stakeholder focus group involving port authorities, concessionaires, shipping companies, and the Harbour Master’s Office, and was applied using the multi-criteria TOPSIS decision methodology, complemented by sensitivity analyses and adjustments for different port types (cargo, passenger, fisheries, marinas). The results show that the best-performing models achieved C* values between 0.514 and 0.529, confirming the robustness of the evaluation framework. Overall, the findings indicate that the optimal charging model is context-dependent, with No-Special-Fee systems without special charges favoured in passenger and leisure ports, and Prepaid + Reimbursement models more suitable for cargo and fishing ports. The paper concludes with policy recommendations aimed at increasing transparency, ensuring consistent reporting, and aligning CRS models more closely with EU environmental objectives.

Marine pollution from plastic pellets, small granules used as a raw material for plastic production, is a growing environmental problem with grave consequences for marine ecosystems, biodiversity, and human health. This form of primary microplastic is increasingly becoming the focus of environmental policies, owing to its frequent release into the marine environment during handling, storage, and marine transportation, all of which play a crucial role in global trade. The aim of this paper is to contribute to the ongoing discussions by highlighting the environmental risks associated with plastic pellets, which are recognized as a significant source of microplastics in the marine environment. It will also explore how targeted education and awareness-raising within the maritime sector can serve as key tools to address this environmental challenge. The study is based on a survey conducted among seafarers and maritime students to raise their awareness and assess their knowledge of the issue. Given their operational role in ensuring safe and responsible shipping, seafarers and maritime students are in a key position to prevent the release of plastic pellets into the marine environment through increased awareness and initiative-taking practices. The results show that awareness is moderate, but there is a significant lack of knowledge, particularly in relation to the environmental impact and regulatory aspects of plastic pellet pollution. These results underline the need for improved education and training in this area, especially among future and active maritime professionals.

The aim of this paper is to analyse the main scientific contributions in the field of sustainable seaports, with a particular focus on passenger seaports and passenger seaports’ commitment to sustainability. The focus of this analysis is on the methods used to improve and develop a sustainable seaport. A search of the Web of Science Core Collection that addresses this topic consists of scientific articles published from 2012 to 2022. The articles are divided into seven groups by research area (technical/technological, legal, organisational, economic, social, environmental, and other) and five groups by applied methodology (literature review, theoretical approach, qualitative approach/methods, quantitative approach/methods, and other). The results show that most of the papers were published in the field of the environmental impacts of a sustainable seaport and a sustainable passenger seaport. In addition, most papers used quantitative approach/methods.

The description of sound as a form of energetic pollutant is very complex as is also its impact on aquatic life. Human activities causing continuous and implosive underwater noise, such as marine traffic, maintenance of ships, coastal tourism, marine research, military, offshore energy platforms, generation of ocean energies and construction operations are expected to increase. The paper analyses current approach to minimise the impact of underwater noise and limit its emissions, examines regulatory approach and discusses the possibilities to control this type of pollution in order to ensure the preservation of natural underwater soundscape. The timely implementation and further development of the European Marine Strategy Framework Directive and its provisions related to underwater noise is of exceptional importance for the Adriatic Sea, which is facing increasing pressure from various industries generating underwater noise.

As nautical tourism and recreational activities involving boats have become highly popular, research interest on various effects of nautical tourism is also increasing. This paper aims to analyze the main scientific contributions in the field of nautical tourism and its impact on the environment. The focus of the analysis is on the methods used to estimate and model recreational boating activities. Since nautical tourism plays a crucial role in the context of the growth and development of the economy, it is necessary to consider the environmental component of its development. The background objective of the paper is to provide a representation of environmental descriptors, i.e., to highlight in particular the environmental impact of nautical tourism. A search on the Web of Science Core Collection, touching on this topic, is composed of scientific papers published in the period 2010–2021. The papers examined are divided into five categories according to the impact of nautical tourism they study: Environmental, Economic, Social, Technical or Other. The results show that most papers were published in the area of environmental impacts of nautical tourism, with most papers examining invasive species, antifouling and impacts on species. The analysis showed that the negative impacts were mainly studied individually. Based on the analysis and evaluation of the scientific publications, a basic recommendation is given for the construction of a model to estimate recreational boating activities and its impact on the environment.

Marine transportation is considered to be one of the most important aspects of global transportation services. Due to the increase in marine transportation, there are significant impacts on the marine environment. One of the possible measures for mitigation of the environmental impact could be switching to environmentally friendly fuel. However, the alternative fuel selection process is considered to be a problem due to various criteria to be considered and stakeholders that should be involved in the selection process. The aim of this paper is to demonstrate the application of multicriteria analysis as a decision-support tool for the alternative marine fuel selection problem in coastal marine traffic. The suggested methodology takes into account environmental, technological, and economic aspects, and ensures the participation of different stakeholders in the selection process. The priority ranking of the alternatives is based on a combination of the Analytic Hierarchy Process (AHP) and Simple Additive Weighting (SAW). The implementation of this method considers the involvement of relevant stakeholders through evaluation of the criteria weights and performance of each alternative with respect to each criterion. The method is applied for the case study of Croatia, where the results demonstrated that the best alternative for all stakeholders is electric propulsion, even though there are differences in opinions and perceptions with respect to the objectives and criteria. The findings of this analysis, likely the first of this type in this area, can serve as a solid basis for strategic planning.

The aim of this paper is to analyze the available data on recorded ship deficiencies during ship inspections which are related to pollution prevention. The purpose of these inspections regulated under the different Port State Control (PSC) regimes’ Memorandum of Understanding (MoUs), is to detect and disable the operation of substandard ships. The data obtained were sorted according to the six Annexes of the International Convention for the Prevention of Pollution from Ships (MARPOL) Convention, and a comparison was made within the scope of each Memorandum of Understanding by each of the Annexes and antifouling system. By using a Chi-Squared test and correlation analysis, MoUs are compared and analyzed. The conclusions thus obtained provide an insight into the most common deficiencies regarding pollution prevention in the world fleet, revealing which standards are most often met and which are trying to achieve a better degree of compliance with the standards envisaged by law.

The amount of waste generated is becoming an increasing problem both in terms of inefficient use of resources and its harmful effects. Large quantities of waste originate from land, but a certain amount of waste is generated at sea, in which shipping holds its share. A recent analysis for 2015–2016 has rated the Croatian ports of Dubrovnik, Split, and Zadar in the top 10 out of 20 main cruising ports in the Adriatic Sea. As it is clear that a large number of persons present onboard generate a large amount of waste, the aim of this paper is to estimate the amount of waste (plastic, domestic, and food) and examine the significance of its increasing quantity produced by cruisers in the three main cruiser ports in the Croatian part of the Adriatic Sea for the period 2014–2017. Cruise calls correlation, together with repeated measures one-way Analysis of variance -ANOVA, showed that a future increase in the port calls for Zadar can be expected while, for the port of Dubrovnik, a decrease is projected, which is in correspondence with the taken measures for a reduction in the adverse effects of the cruise industry. Regarding the type of waste, domestic waste contributes the most with 62%, followed by the plastic waste with 26%, and food waste, which makes only 11% of the total amount of waste for that year. Waste minimization practices and further recommendations for the improvement of waste management practices are presented and put into relation with specific measures to protect and preserve the quality of the environment.