Transboundary Management of a Common Sea in the Gulf of Venice: Opportunities from Maritime Spatial Planning in Italy and Slovenia

Abstract

Italy and Slovenia have recently adopted their first Maritime Spatial Plans (MSP). These plans belong to a new generation of spatial planning acts that introduce numerous innovations. This article presents the differences and similarities between the Italian and Slovenian MSP. The aim is to determine how a new planning approach can support joint spatial development and management in a transboundary perspective with particular reference to the cross-border area of the Gulf of Venice. Descriptive and comparative scientific methods were applied in the study. We analysed the structure of both plans and the content of the individual planning instruments and tools for three key sectors: Fisheries, Maritime Transport and Nature Conservation. We found that both plans offer new opportunities for transboundary spatial coordination and planning, while the process of preparing the plans themselves is particularly important. Both plans provide instruments to address transboundary environmental impacts, spatial development and sectoral management regimes. The implementation tools include provisions on the spatial, temporal and technical conditions for carrying out a particular activity at sea. The Italian plan adopts a strategic approach that offers possibilities for intersectoral and cross-border planning coordination. The Slovenian plan is more detailed and binding. Regardless of individual differences, the adoption of both plans represents a major step towards achieving the common goals of sustainable spatial development in the shared marine area of the Gulf of Venice.

1. Introduction

The development of Maritime Spatial Planning through the establishment of the European Union (EU) Directive 2014/89/EU (Maritime Spatial Planning Directive (MSPD)) [1] is changing practices in managing the marine space in the European seas [2,3]. The Gulf of Venice, located in the Northern Adriatic Sea, is administratively shared by three countries: Italy (IT) and Slovenia (SI) to the north and Croatia (HR) to the east [4]. Due to its exceptional geostrategic position, there have always been many spatial development interests in this area, which have been regulated by various administrative and political practices. The intensive use of the sea and the dense urbanisation of the coastal zone have developed in recent decades in this area, which today represents an extraordinary economic and cultural asset for both Italy and Slovenia [5].

The introduction of MSP is largely concerned with the transboundary dimension of coordinating development interests in space, minimising conflicts, planning environmental and nature conservation objectives and promoting practices of joint transboundary management of the marine environment [6,7,8]. To do so, MSP requires the coordination of sectoral policies and asks for integration and harmonisation of their respective objectives. The Ecosystem Approach is indicated by the MSPD as an overarching principle (Art. 5) and an effective monitoring of the implementation of plans and the changes in the environmental and economic sector condition is foreseen (Art. 14). Apart from the minimum requirements indicated in the MSPD (Art. 6), each country has been free to shape its plans according to the national will. The MSP developed across the European Union are therefore diverse [9] under different perspectives (the European MSP Platform available online (https://maritime-spatial-planning.ec.europa.eu/, accessed on 25 June 2025) provides relevant contents): level of detail (strategic vs. prescriptive), legal dimension (legally binding or not), different sectors, organised around different governance assets, and different spatial scope (linked to different extensions of sea areas). This diversity applies to the Gulf of Venice too, where the Italian MSP for the Adriatic Sea and the Slovenian one show profound differences and certainly have a different approach to the management of the common sea. These two instruments are changing the meaning and scope of existing planning processes at sea and on the coast in the area.

When considering transboundary management in the Gulf of Venice, it is important to recall the long history of collaboration between the two countries. The beginnings of bilateral cooperation between Italy and Slovenia on coastal and maritime environmental matters, which also extended to the sea and the coast, date back to the second half of the past century, when the former Socialist Federal Republic of Yugoslavia (SFRY) and Italy planned certain joint projects within the framework of intergovernmental agreements [10]. During this period, for example, a joint fishing zone in the Gulf of Trieste was planned, also if it was never implemented in practice [11]. After, intergovernmental cooperation between Italy and Slovenia in the field of protection and sustainable management of the marine environment has been constantly promoted, mainly through international commitments, such as the Barcelona Convention and its protocols, EUSAIR, and numerous EU sectoral policies and directives in the field of marine environment management [12,13].

The Joint Commission for the Protection of the Adriatic Sea should also be mentioned. Based on the 1974 agreement between Italy and Yugoslavia on cooperation for the protection of the waters of the Adriatic Sea and coastal zones between Italy and Yugoslavia, the Commission was re-established in 1992 between Italy, Slovenia and Croatia. Montenegro joined later, making it a quadripartite commission. The Commission supports different institutions in coordinating issues such as ballast water, pollution control, traffic separation schemes, protection of environmental values and cooperation on resource conservation strategies. In 2021, Italy, Croatia and Slovenia reaffirmed their commitment to the Commission to implement the EU Biodiversity Strategy by 2030, including the 30% commitment for marine conservation (Joint Declaration, Ljubljana, April 2021, source [14]).

At the same time, European and international projects (CAMP, SHAPE, SUPREME, Portodimare, MED-MSP, etc.) that promoted the development of MSP also contributed to intergovernmental cooperation. Many spatial challenges with transboundary dimensions were profiled in the implementation of these projects (e.g., maritime issues, habitat protection, etc.), and at the same time, numerous intergovernmental associations and informal networks of expert groups were formed, which later contributed significantly to the preparatory processes of the first generation of MSP [15]. One of the most recent and notable joint formal decisions on the use of the sea is certainly the example of the intergovernmental agreement on the spatial organisation of the separate shipping regime in the northern Adriatic.

In this paper, we present and discuss the existing differences between the MSP of Italy [16] and Slovenia [17] and compare the different planning tools used therein, to provide an integrated picture of how the MSP process could support the common management of the Gulf of Venice area in a transboundary perspective. The paper presents the preparation process of the plans in the two countries and their main features; the tools provided by the plans to manage uses of the sea are presented and discussed with specific reference to three key sectors for the area: maritime transport, fisheries, and nature protection. The ways MSP can practically support the joint management of a common sea to achieve a common maritime governance are then discussed. In this context, the following questions are important for the present research:

• In the context of the cross-border perspective, what are the elements introduced by the MSP in the area?
• How do the two plans address the three key sectors in the cross-border area?
• What is the added value of the new plans in the field of maritime spatial planning in both countries?

2. Materials and Methods

2.1. The Study Area

Maritime transport and port activities are major economic drivers in the area [18]. The Gulf of Venice (Figure 1) has a high strategic value since it represents a pivotal junction of the commercial route that connects Europe with Asia through the Suez Canal. The ports of Venice, Trieste and Koper belong to the so-called NAPA (North Adriatic Ports Association), established in 2010. In addition to being major transport players at the local, national and European levels, NAPA ports also serve as main nodes in the Baltic-Adriatic and Mediterranean corridors—which are two priority corridors of the European TEN-T network—and in the Motorways of the Sea of the Eastern Mediterranean. Maritime tourism, including cruising, boating, yachting and bathing tourism, represents another economic pillar in the area, also linked to a flourishing and innovative boat construction and shipyard industry. In this area, the fishery sector has a long tradition and has great socio-economic importance. At the same time, it has been responsible for intense pressure on natural stocks and habitats, with bottom trawling playing a relevant role in this sense. At present, the fishery resources of the Adriatic Sea are under intense and increasing pressure from human activities, and the combined effects of fishing and habitat degradation have led to alarming reductions in many exploited fish stocks [8,19,20,21]. In addition, aquaculture (mainly shellfish farming), sand extraction and other economic activities related to the marine environment have coexisted in the area for a long time. Regardless of the state-administrative division, the area represents a unique, interconnected and sensitive marine environment.

Today, spatial capacity constraints at sea are also relevant in this crowded area that should be addressed holistically, regardless of national boundaries.

At the same time, these developments dramatically endanger the valuable natural features of the sea area, its habitat and species, as well as the ecosystem services they provide. The Northern Adriatic ecosystem is rich in biodiversity and hosts peculiar habitats, including lagoons, estuaries, seagrass meadows, sandy and muddy seabeds, and rocky outcrops. Important biodiversity coastal hot-spots are the Venice, Caorle, and Marano-Grado lagoons, the Strunjan peninsula, and the Debeli Rtič that provide essential shelter and feeding grounds for diverse species of fish, crustaceans, and migratory birds. The area’s shallow waters and wide continental shelf support a nutrient-rich environment, fostering phytoplankton and zooplankton growth at the base of the food chain. Among the peculiar ecological features of this sea area, the sea bottom, largely characterised as soft bottom, is scattered with biogenic outcrops, locally known as “tegnùe” or “trezze”, which are considered biodiversity hotspots (rocky outcrops) [22,23]. Several cetacean species can be found in the area, but only the bottlenose dolphin is a regular inhabitant [24].

All these ecological features are under pressure from anthropogenic activities: pollution, including plastics, underwater noise, seabed disturbance due to trawling, destruction of coastal habitat due to urbanisation and over-tourism, and overfishing.

2.2. Approach to the Analysis of MSP

The research was conducted in three phases. In the first phase, we carried out a basic comparison of the MSP of the two countries:

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We defined their structural composition using the descriptive research method. We focused on defining: (a) the basic starting points for the preparation of the plans, (b) the structure and content of the plans (provisions) and (c) the instruments for implementing the plans (measures).

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We analysed the mutual similarities and differences between the two plans using the comparative method.

In the second phase, we analysed individual provisions of both plans for three selected sectors (sea uses): Fisheries, Maritime Transport and Nature conservation.

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In a first step, we defined the basic concepts regarding the instruments and tools that determine the planning and management of activities and uses at sea.

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In a second step, we examined the content of the individual provisions of the Italian and Slovenian plans in detail and carried out a mutual comparison. We referred to various sectoral materials used in the preparation process of the plans (e.g., the National Fisheries Management Plan, the Regulation on Special Protection Areas (Natura 2000), etc.).

To analyse and compare our plans, some definitions were key:

Instrument: Context-related or process-related element, procedure or governance element, strategic elements orienting or guiding the plan or its process (preparation, implementation, monitoring, revision), e.g., principles, legislative acts, guidelines, strategies.

Tool: A specific provision of the plan, related to its implementation and aimed at achieving a precise objective, e.g., regulating a specific activity or use, regulating activities and uses in a specific area.

Notably, the provisions in both plans differ in terms of content and scope. This is primarily a consequence of two completely different situations, both in terms of the governance organisation of the two countries, including MSP governance, the administrative structure of the sectors and, of course, the major differences in the spatial extent of the two national seas. The specific features of the content of the individual provisions of MSP for the two countries are listed separately below.

In the third phase, we summarised the results and defined the main contribution of the plans (main subject of the regulation, tools and outcomes).

The open access programme “QGIS Version 3.40 Bratislava” was used for the preparation and processing of the graphic material.

3. Results

3.1. Key Elements of the MSP in the Two Countries

In the following paragraphs, we present the structure and the main contents of the Italian and the Slovenian MSP. We also present the key planning elements relevant for the management of the three key selected sectors: fisheries, maritime transport and nature conservation.

3.1.1. Key Elements of the Italian MSP

Italy has developed three distinct MSP corresponding to the three marine areas under national sovereignty: the “Adriatic”, “Ionian-Central Mediterranean” and the “Tyrrhenian-Western Mediterranean” maritime area.

The three plans have been approved with the Ministerial decree n. 237 25 September 2024. The plans’ provisions consist of strategic-level indications and guidelines, to be used as a reference for other planning actions (at sector or sub-regional and local levels) and the granting of concessions or authorisations.

• Main elements

The planning is implemented through a multi-scalar approach to achieve a level of strategic planning, but at the same time providing, wherever necessary and possible, elements and forecasts of greater detail [25].

The vision and the strategic objectives of each maritime area are defined taking into account reference documents (plans, standards, strategies, etc.) at the international, European Union and national level, related both to environmental, landscape and cultural heritage aspects, and to socio-economic aspects related to the needs of the different sectors. Strategic objectives are identified in relation to three cross-cutting principles (i. Sustainable Development, ii. Protection and conservation of species, habitats and ecosystems, iii. Landscape and cultural heritage) and eight sectors (1. Safety of navigation, maritime and surveillance, 2. Maritime transport and ports, 3. Energy, 4. Coastal defence, 5. Fisheries, 6. Aquaculture, 7. Coastal and maritime tourism, 8. Research and innovation). Strategic Objectives apply to the entire domain of the three plans. In addition, Specific Objectives have been identified for the territorial waters under the competence of the coastal Regions. These objectives are different for the different so-called sub-areas under the competence of the different Regions, and they respond to local specificities and needs.

The plans have been configured by the domestic law transposing the MSPD as superordinated to all other plans and programmes that insist on the same area, not only those related to marine waters, but also those concerning land-based activities that may affect marine waters.

• Tools for the implementation of the plans

The implementation of the plans relies on two major tools.

1. Management measures, identified at the national level and linked to strategic objectives. These measures apply to the entire domain of the plan. In addition, some specific measures have been identified by the Regions. They are linked to the Specific Objectives and are valid for the territorial waters under each region’s competence. These measures are complemented by those defined in other cross-cutting (e.g., the Program of Measures of the Directive 2008/56/EC, Marine Strategy Framework Directive—MSFD PoM) and sector plans (e.g., management plans of Marine Protected Areas (MPAs) and Natura 2000 sites) relevant for the management of the sea.

The Italian MSP consider the following typology of measures:

S = Spatial measures; they are related to the definition of spatial aspects and areas in which the activities can take place.

T = Temporal measures; they are related to the definition of limits or conditions that regulate or define the performance of the activities over time.

TE = Technical and technological measures; they are related to the use or adoption of specific technologies or techniques.

M = Monitoring, control and surveillance measures; they are related to the acquisition of data relating to the performance of maritime activities, compliance with rules or regulations, the effects on the marine environment, and the effects in terms of interaction with other uses.

G = Governance measures (G); they concern procedural and organisational mechanisms, including multi-level ones.

E = Economic and financial measures (E); they identify actions relating to financial resources to support maritime activities (also within the existing programming, such as the regional POR-FESR and/or FEAMP).

A = Other types of measures (A); such as training, education and communication activities.

In addition, measures are attributed to different typologies:

I—Guidelines, primarily addressed to public administrations or planning instruments.

P—Regulations, established by the plan to govern the use of maritime space (e.g., in terms of spatial and temporal modalities for permitted activities).

i—Incentives, measures aimed at promoting specific objectives.

A—Actions, concrete initiatives (e.g., consultations, studies, analyses) carried out by or on behalf of competent authorities, possibly in partnership with private entities.

2. Zoning provisions, providing spatial indications on where to prioritise the development of some uses and activities and the type of relationships these uses have one each other and with other uses. Zoning is implemented in the Italian MSP by the identification of Planning Units (PU). Each PU is assigned a typological attribute:

G = Generic Use or Areas in which all uses are generally permitted, with specific and reciprocal regulation mechanisms defined or to be defined within the scope of national and international regulations or sector plans, to guarantee safety, reduce and control environmental impacts and promote coexistence between uses.

P = Priority Use or Areas for which the Plan provides indications of priority of use and development, also indicating the other uses to be guaranteed or permitted through reciprocal regulations and with the priority use identified.

L = Limited Use or Areas for which a prevalent use is indicated, with other uses that may be present, with or without specific limitations, if and when compatible with the prevalent use.

R = Reserved Use or Areas reserved for a specific use. Other uses are permitted exclusively for the needs of the reserved use or subject to exemptions and concessions by the person responsible or manager of the reserved use.

Figure 2a summarises the essential elements of the Italian MSP at the national scale, including some relevant figures relative to the plan provisions: number of strategic objectives, national measures, and planning units. The whole spatial scope of the three national plans is illustrated by Figure 2b. The map in Section 3.2 zooms in on the area of the Gulf of Venice (our study area) and illustrates the zoning provisions, namely the planning units identified both in the territorial waters and in the offshore area. The typology of each PU is also indicated (P, L, G), and the uses which are identified as priority ones are shown. The study area for this article includes two coastal sub-areas of the Italian MSP for the Adriatic, extending up to 12 M (22.224 m): sub-area A1 (under the competence of Friuli-Venezia Giulia region) and sub-area A2 (under the competence of Veneto region). The study area also includes the northernmost portion of sub-area A7, extending offshore beyond 12 M (22.224 m) up to the midline.

The Italian MSP represent a comprehensive and innovative entity in the national spatial planning system, both in terms of the process of their preparation and in terms of the individual provisions.

Table 1. Summary of key instruments and tools of the Italian MSP.

Instruments
Scope of the instruments
Definition of institutional context and context conditions	Legislative Decree 17 October 2016, n. 201 o Identification of the Competent Authority: Ministry of Infrastructures and Transport o Identification of the process-driving entity and its composition: Inter-ministerial Coordination Table o Identification of the entity responsible for the plan preparation and its composition: Technical Committee o Identification of procedural key aspects: public participation and access, data use and sharing, cooperation with EU Member States and Third Countries, financial provisions
Guidelines for MSP preparation and their key contents	Decree of the Presidency of the Council of Ministries 1 December 2017 o Process to be followed for plan preparation o Methodology for plan preparation o Expected contents of the plan o Geographic scope o Temporal extent of the plan
Plan of the Sea 2023–2025	The strategy for the sustainable management of marine resources and the sustainable development of the Italian maritime system o overarching objectives on the use of the marine resources and the blue economy, taken into account by the MSP, in particular to define their visions and strategic objectives
Coordination of activities at sea	MSP o Vision and strategic objectives
Tools
Scope of the tools
Spatial identification of areas for activities and uses (zoning)	Identification of sub-areas, identification of Planning Units (PUs) and their attribution to typology, identification of priority, limited or reserved uses
Implementation provisions	Management measures identified at the national level and linked to strategic objectives
More spatially detailed provisions	Specific objectives and related measures identified at the regional level by regional authorities
Monitoring of the implementation of the plan	Monitoring system and indicators

summarises the instruments and tools that enable the development and regulation of individual activities at both national and cross-border levels.

3.1.2. Key Elements of the Slovenian Plan

The Maritime Spatial Plan, as the first such plan ever in Slovenia, was approved by the Government Decree on the MSP of Slovenia No. 00719-28/2021 of July 2021. The plan defines the spatial development of the Republic of Slovenia at sea and contains sectoral spatial development objectives and formal tools (named measures) for achieving these objectives, as well as directions for the harmonious use of space in the coastal zone (land–sea).

In the structure of the national spatial planning system, the plan represents a completely new type of so-called hybrid spatial planning act that combines the strategic and implementation planning levels. The plan is formally defined as: (a) a strategic spatial development act (plan), as its preparation represents an instrument for achieving mutual coordination of spatial development objectives and at the same time as (b) an action programme for the implementation of the Spatial Development Strategy of Slovenia (SDSS) at sea, as it contains appropriate tools (measures) for achieving the defined objectives.

• Main elements

The plan is prepared on the basis of various starting points (Figure 3a). The key starting points are:

(a)

International commitments (conventions, protocols, etc.) in the field of sustainable development and protection of the marine environment, as well as joint/common development policies (e.g., fisheries, nature protection, etc.), in which individual sectoral spatial objectives are agreed at the EU level development.

(b)

The SDSS, which determines the fundamental spatial development goals at the national level.

(c)

More detailed sectoral development objectives at the national level.

(d)

Spatial development objectives at the local level, which are determined by municipalities’ spatial plans (such as the subsidiarity of the MSP).

(e)

The national Marine Environment Management Plan, which already includes various protection and administrative aspects and indicators for achieving and monitoring a good state of the marine environment.

The central part of the plan is the so-called spatial development design for twelve sectoral fields (mariculture; fisheries; facilities and infrastructure for the research, exploitation and extraction of oil, gas and other energy sources, minerals and aggregates and the generation of energy from renewable sources; maritime affairs and maritime transport; defence and protection against natural and other disasters; nature conservation; extraction of raw material; scientific research; submarine communications cables and pipelines; tourism, sport and recreation; protection of immovable cultural heritage; urban development). Location, spatial and other implementation provisions are defined for each sectoral field. They are defined as tools for spatial planning and spatial management. There are also additional provisions for monitoring the implementation of the plan.

A special component of the plan is also the provisions for the development of activities in the narrow coastal zone on land, which are directly linked to activities at sea (Figure 3b). In this sense, the plan implements the content of the Protocol on Integrated Coastal Zone Management in the Mediterranean (ICZM, 2nd and 3rd paragraphs) and thus establishes the baseline of the coastal strip in the sea (150 metres) and on land (100 metres), supported by detailed mapping and a set of recommendations and conditions for the sustainable use and management of this space.

• Implementation of the plan

Implementation of the plan has several directions and different tools. In principle, there are four indirect or direct ways of implementation:

• Directly through the provisions of the plan, which specify the spatial implementation conditions (graphically and textually) for achieving the goals of spatial development.
• Directly through the spatial measures defined in this plan.
• Directly through the management measures defined in this plan.
• Indirectly through spatial provisions, which are implemented in subordinate acts or documents within the jurisdiction of spatial planning authorities in the implementation of all activities, regimes and uses at sea.

Here, the individual provisions have the function of a tool that determines the details:

L = location.

A = area.

S = scope of activities (optional: P—priority use, L—limited use, R—reserved use).

R = special regime or special requirement.

But it can also be a combination of different provisions. A more detailed breakdown is shown in the next chapter (Section 3.2).

It should also be emphasised in the Slovenian plan that, despite the tools listed, which are defined in the form of implementing provisions, the preparation of the plan itself is to be understood as a special instrument (

Table 2. Summary of key instruments and tools of the Slovenian MSP.

Instruments
Scope of the instruments
Definition of institutional context	o International commitments o National legislation o Sectoral development strategies
Guidelines for MSP preparation	o Methodology for plan preparation o Expected contents of the plan
I. Process instruments:	Managing the coordination of interests in the space o Determination of strategic priorities (national and cross-border) o Determination of sectoral priorities o Determination of quotas (spatial extent) Determination of base conditions o Determination of authorities for the implementation of the plan o Determination of subsidiarity o Timetable and validity of the plan
Tools
Scope of the tools
II. Implementation tools	Location and scope o Detailed spatial determination of areas of activity and use o Tentative determination of locations of activity and use Implementation conditions o Determining implementation conditions for activities and uses o Determining the regime of activity and use Monitoring of the implementation of the plan - System and indicators

). It is precisely in this process that numerous decisions are made that have an impact on the implementation level. These certainly include the implementation of international commitments, the selection of stakeholders that form the starting points for the development of a particular sector, and the process of preliminary coordination of interests in the space in which the priorities must be set. This is of exceptional importance in the Slovenian case, as the limited spatial dimension of the national sea does not allow for the realisation of all existing and desired interests. It is equally important in terms of cross-border coordination. Fundamental decisions are already made during the plan preparation phase, e.g., on transboundary environmental impacts, initiatives for transboundary habitat protection, etc.

3.1.3. Findings: Similarities and Differences Between the Two Plans

The results described above show how the Italian approach was adapted to the extensive spatial dimension of the national sea(s) (three plans covering different marine areas and sub-areas), while the small Slovenian sea is the subject of a single plan that defines only the territorial sea and internal marine waters. Regardless of the differences in spatial scope, both plans are based on the common MSPD and other international commitments. Consequently, they provide clear tools (spatial and management measures) for the development of activities and uses in space. Both plans contain provisions for individual sectors and, at the same time, provide appropriate tools and instruments for the cross-border coordination of interests in space.

It should be emphasised that in both cases:

(a)

The process of plan preparation ensures decision-making on strategic spatial development objectives and the coordination of sectoral interests and development priorities. This can be described as the “process instruments of spatial planning for achieving spatial development objectives”.

(b)

The implementation of the plan itself enables the spatial regulation of activities and uses (locations, extent, conditions) and the implementation of monitoring the state of the space and the effectiveness of the implementation of the plan. This can be described as “spatial planning tools for achieving the objectives of spatial development”.

Another significant difference is that Slovenia, regardless of the plan, does not have such a branched administration responsible for the sea as Italy. In both countries, however, the new plans take a different approach to conventional planning and define the sea as its own spatial development entity. This is particularly important in a case such as the Gulf of Venice, which is surrounded by various spatial development interests and various state administrative mechanisms (IT-SI-HR).

3.2. Instruments and Tools for the Management of Fisheries, Maritime Transport and Nature Conservation

3.2.1. The Italian Plans

In this paragraph, some details are provided on the provisions relevant to the three sectors selected for the comparative analysis. It is worth mentioning that the Italian MSP include a portfolio of 80 measures relevant at the national level. Only some of them are referred to in this article. The full portfolio can be consulted at https://www.sid.mit.gov.it/documenti-piano (Italian only). As for the spatial provisions (figures included in this paragraph), reference is made to the part of the Adriatic Sea plan that falls within the study area considered in this article.

• Fisheries

Concerning fisheries (Figure 4), the measures in the MSP focus on fleet modernisation, especially small-scale fisheries, by improving energy efficiency and safer working conditions in ports. Training programmes align with EU rules on sustainable fishing—as exemplified in the following, while energy optimisation promotes vessel efficiency and the use of renewable energy across the supply chain.

Measures also support aligning fishing capacity with EU and national plans to avoid overexploitation and enhance sustainability. Small-scale fisheries management includes mapping fishing grounds, monitoring stocks, and strengthening coastal communities’ skills. Co-management with MPAs and local fishing plans link with conservation efforts and support economic viability.

Marine ecosystems are safeguarded by protecting Essential Fish Habitats (EFH) through spatial management. International and multi-level governance improve the regulation of shared fishery resources and interactions between fishing systems.

To enhance compliance and safety, international dialogue is reinforced to prevent disputes and secure the Italian operator. Vessel tracking pilots expand monitoring through Vessel (VMS) and Automatic Identification Systems (AIS), supported by financial incentives.

Overall, these measures aim to foster a sustainable, competitive, and well-regulated fisheries sector, balancing economic growth with conservation.

Based on the above, we can highlight the following effects:

(a)

Direct transboundary effects: Regulation of fisheries on species, and international cooperation support sustainable resource management goals (e.g., improved state of fish stocks) in the study area.

(b)

Indirect transboundary effects: Fleet modernisation and energy efficiency bring economic benefits, helping offset present revenue losses from reduced catches and the fleet cuts. Such innovations would likely be adopted also by the Slovenian fisheries sector, thanks to cross-border exchanges between the operators of the sector.

• Maritime transport

Regarding maritime transport and port management (Figure 5), the Italian MSP include measures to improve sustainability by reducing environmental impacts, boosting energy efficiency, and supporting the clean energy transition.

Key measures involve identifying high-impact maritime traffic areas (“hot spots”) to limit air and water pollution, waste dispersion, underwater noise, and vessel collisions. Traffic management will be enhanced through, e.g., Particularly Sensitive Sea Areas (PSSAs), Areas To Be Avoided (ATBAs), and Traffic Separation Schemes (TSS) to regulate routes and protect marine ecosystems. To reduce underwater noise, spatial and technological measures will be implemented in line with MSFD Descriptor 11. Dredged sediment management will also be improved through regional coordination and mapping of disposal sites.

The plan promotes alternative fuels such as Liquefied Natural Gas (LNG), hydrogen, and ammonia, with refuelling and charging infrastructure at TEN-T ports. Cold ironing (shore power) will further cut emissions from docked ships.

Port waste management will be strengthened by harmonising collection, increasing recycling, and reducing plastic waste. Italian ports will also pursue sustainability certifications (e.g., European Clean Ports, Environmental Management System—EMS, Port Environmental Review System—PERS).

Finally, the plan ensures port master plans align with MSP updates, balancing expansion with environmental protection to foster a resilient, competitive, and sustainable maritime sector.

Based on the above, we can highlight the following effects:

(a)

Direct transboundary effects: Identifying, monitoring and managing hot spots of maritime pressures—including transboundary pollution, noise and megafauna corridors—would benefit the transboundary area through joint measures, e.g., for pollution reduction, protection of marine mammal corridors (e.g., cetaceans), and management of impact on coastal and benthic ecosystems.

(b)

Indirect transboundary effects: Solid waste management inventories and guidelines would provide a shared framework for waste reception and recycling, reducing incentives for illegal discharges and fostering circular economy practices at a cross-border level. Specific attention to plastic waste and marine litter as common issue is key. Expanding Information and Communication Technologies (ICT) and digital infrastructures would further enable cross-border digitalisation of logistics chains, enhancing interoperability and lowering environmental impacts.

• Nature conservation

Regarding nature conservation (Figure 6), the Italian MSP aims to integrate biodiversity conservation into planning, strengthen monitoring, and support ecosystem restoration. A technical working group will ensure updated knowledge on species, habitats, and environmental trends is included in MSP, in line with MSFD, Natura 2000, and the Biodiversity Strategy 2030 targets.

The plans promote cumulative impact assessments and continuous monitoring of marine megafauna (body mass, ≥45 kg) [26] through sonobuoys and satellite surveys. Priorities include expanding MPAs and Natura 2000 sites, identifying Other Effective Conservation Measures (OECMs) and ecological corridors to build a connected network of protected areas. A multi-scale approach will guide conservation priorities, ensuring integration with land–sea management.

The forthcoming National Environmental Restoration Plan will set priority areas. MSP will align this with implementation and monitoring, leveraging knowledge from European research projects and the National Biodiversity Centre (PNRR-MUR).

Overall, these measures aim to support a science-based, integrated approach to marine conservation and restoration, balancing maritime development with biodiversity protection.

Based on the above, we can highlight the following effects:

(a)

Direct transboundary effects: Expanding the MPA and Natura 2000 network on the Italian site would benefit the whole study area by enabling biodiversity corridors. Potential for cross-border MPAs/OECMs will be created, also thanks to the support of the MSP’s provisions in the two countries.

(b)

Indirect transboundary effects: Stronger transboundary cooperation will grow in key scientific areas such as habitats and species (e.g., marine megafauna) mapping, and in shared methods for cumulative impacts and user conflicts/synergies assessment.

Table 3. Planning and management tools specific to the three sectors: subjects, nature of the tools, and expected results (IT).

Fisheries	Maritime Transport	Nature Conservation
Main subjects of planning and management
- modernisation - energy efficiency - coordination of different segments within the sector (e.g., small-scale fisheries vs. trawling) - small-scale fisheries - engagement in nature protection - co-management of protected areas - local communities - Essential Fish Areas - multi-level governance for fisheries - illegal fishing	- environmental pressures - new traffic management areas - alternative fuels - disposal of dredged materials - decarbonization - decarbonization in ports - management of solid wastes - areas for port development - port certification - integration of port plans with MSP	- integration among MSP, MSFD and Biodiversity 2023 actions - monitoring cumulative impacts - monitoring marine megafauna - expansion of MPA and Natura 2000 network - OECMs - Ecosystem Services - land–sea interaction in nature protection - nature restoration
	Tools
- PUs where fishery is identified as a priority use - management measures at the national or regional level	- PUs where maritime traffic is identified as a priority use - management measures at national or regional level	- PUs where nature protection is identified as a priority use - management measures at national or regional level
	Expected result
- achieve sustainable development of fisheries - achieve protection and restoration of fish stocks - achieve sustainable development of small-scale fisheries - achieve international cooperation in fisheries management - stop illegal fishing	- map and reduce environmental pressures from the sector, particularly in hot-spot areas - achieve better management of the sector, reduce conflicts with other uses and marine protection - optimise waste collection and compact marine litter pollution - decarbonization of the sector - port decarbonization - enhancing the competitiveness of Italian ports	Applying a coherent Ecosystem Based Approach (EBA) - achieve the extension of EU marine protection to 30%, of which 10% in a stringent manner, by 2030 - ensure the coherent implementation of MSP measures with spatial MSFD measures - achieve integrated land–sea planning for nature conservation aspects - contribute to marine restoration objectives

summarises the key elements that are subject to regulation for the three sectors. The table also identifies the tools put in place to implement the provisions and the expected results.

3.2.2. The Slovenian Plan

The Slovenian MSP is a hybrid spatial act, as it combines both strategic and implementation components. Already in its formal definition, the MSP is defined as an Action Programme, which sets out: (a) the strategic national spatial development objectives and the individual sectoral objectives, (b) the hierarchy of development priorities, but also the implementation level in the form of: (c) the tools to achieve these objectives, namely: provisions in the form of spatial implementation conditions and spatial and management measures (tools for determining the location, spatial extent, conditions and regimes for the implementation of activities and uses on the sea).

Based on a detailed content analysis of the provisions (for three selected areas—a chapter in the MSP called Measures for the Implementation of the Plan), we have found that the provisions are very diverse, as they may regulate both spatial and other conditions for the implementation of a particular activity/use, or they may set spatial boundaries or scope, regimes, the requirement of joint or parallel use of the sea, or other conditions depending on the “nature of subject to managed”. They integrate the content of each sector in different ways; some are simply transferred to the new plan (they already existed before), while others are completely redefined (new) and, as such, represent a unique innovation.

For the three sectoral fields covered, the plan lists a total of 33 so-called spatial and management measures, which are defined in the form of planning provisions, which we have classified into six groups with the same function on the basis of their content. For each group, we have defined the so-called status (S) of the provision, which we refer to as a tool:

S 1: Determines the area in detail (location + dimension) for the implementation of a specific activity and use on the sea.

S 2: Determines the general definition of the location and the conditions for the implementation of a specific activity and use.

S 3: Determines the requirement for a special regime when carrying out a certain activity and use.

S 4: Determines the requirement for interconnection when performing a specific activity and use.

S 5: Determines the requirement for control and evidence (record keeping) in the performance of a specific activity and use.

S 6: Determines the requirement and process for ensuring the conditions for the implementation of a specific activity and use.

The results of the analysis of the provisions for the three selected fields are presented below. For each provision, the status, a summary and a comparison with the situation before the plan (MSP), if such a provision existed at all, are defined.

• Fisheries

In the field of fisheries (Figure 7), we recorded two spatial and nine management measures (

Table 4. Features of measures in the field of Fisheries (SI).

No.	Status	Content/Summary of the Provision (Current MSP)
		Spatial measures:
1	S1	Spatially defined fishing areas (regimes and restrictions)
2	S2	The possibility of installing a pilot (test) artificial vertical/horizontal underwater structure is permitted.
		Management measures:
1	S4	Required mutual coordination with other uses, in case of simultaneous implementation
2	S3	Required verification of eligibility and consequences of mullet fishing
3	S3	Required verification of gilthead sea bream catches in the areas of fishing reserves and shellfish farms
4	S5	The appropriate number of special permits (for catching mullet and gilthead sea bream) is determined
5	S5	The competent authorities should supervise the prohibited fishing methods
6	S6	Conditions for the separate collection of waste from fishing activities are required in fishing ports
7	S6	Studying the possibilities and ensuring the appropriate conditions (ecological and other) for the re-fishing of species that were traditionally fished (tuna, lobster, eel, etc.)
8	S6	Arrange the possibilities and provide everything necessary for the cultivation of indigenous species with the aim of repopulation
9	S6	The location for the temporary storage of waste vessels must be determined

). Among them, only the measure that establishes the responsibilities for carrying out the control of illegal forms of fishing is one that was already implemented before the plan. Three measures limiting the spatial areas for the implementation of individual fishing methods and measures for issuing special fishing permits were also partially implemented, but these activities were not fully coordinated with other activities and uses at sea. The remaining seven measures are completely new in the plan. These measures primarily concern the necessary coordination with other uses of the sea, as well as new requirements for the management of fishing waste, the examination of possibilities for the introduction of traditional methods of fishing, measures to improve the repopulation of fish species and conditions for the construction of artificial underwater structures to develop new habitats.

Based on the above, we can highlight the following key measures that have the following effects:

(a)

Direct transboundary effects: The regulation of fisheries on individual fish species ensures the achievement of international sustainable natural resource management goals.

(b)

Indirect transboundary impacts: Measures to limit marine pollution (litter) help to limit the pollution potential of the wider area.

• Maritime transport

In the field of maritime transport (Figure 8), we have identified six spatial and six management measures (

Table 5. Features of measures in the field of maritime transport (SI).

No.	Status	Content/Summary of the Provision (Current MSP)
		Spatial measures:
1	S1	Permanent preservation of the scope of the joint traffic separation system in the Gulf of Trieste
2	S1	Two potential locations for relocation of marine sediment due to the deepening of navigation routes and the international transport port in Koper are envisaged (test and permanent area)
3	S6	Relocation of marine sediment is carried out in case of demonstrably acceptable impacts on the space and environment (nationally defined procedure and conditions)
4	S2	Permanently preserve and develop the existing legal location of small service shipyards for the maintenance of boats and small passenger vessels
5	S2	The possibility of expansion of ports for special purposes is allowed (need/process to prepare a coordinated operational plan for the development of ports at the local level)
6	S2	Expansion of municipal berths, marinas and piers for the landing of passenger transport, a port for international public passenger transportation, possible with the prior preparation of expert grounds, including environmental impact assessment, verification of capacities in the hinterland, etc.
		Management measures:
1	S3	The separation space of the exit navigation corridor from the port of Koper is increased in the south-eastern direction from the boundary of the Debeli Rtič Landscape Park near Valdoltra by adjusting it with the protection regimes in the Decree on the Debeli Rtič Landscape Park.
2	S6	Special activities in the field of maritime transport, sport, tourism, leisure and other nautical recreational activities (e.g., regattas, fishing competitions, labelling special anchoring and safe navigation regimes in the season, determining the permitted locations for the arrival of non-motor tourist vessels along beaches, etc.) can be carried out based on a permit by the Maritime Administration.
3	S4	Links between providers of tourist services and public passenger transportation at sea and on land are established and promoted.
4	S5	The implementation of the legislative provision stipulating that sailing within 250 metres off the coast and navigation with motor vessels within 200 metres off the coast are not permitted must be supervised. The speed of vessels should be restricted.
5	S5	Registering sunken vessels and appropriately emptying fuel tanks—preventing sea pollution.
6	S6	The owner of a waste vessel must ensure further processing of the vessel or its removal. Temporary storage for the vessel needs to be ensured until it is delivered to an authorised collector of waste. In the area of coastal municipalities, a location for the temporary storage of waste vessels needs to be determined, together with the utility companies responsible for waste collection.

). Of the measures that have an equivalent in the previous state, the plan only provides for two measures relating to the creation of conditions for safe navigation. The measures that deal with the possibility of developing ports, municipal moorings and conducting sports and recreational activities at sea have also already been partially implemented in sectoral legislation or strategies, but the plan now formalises them precisely. The other six measures are completely new in the plan. This concerns in particular the creation of completely new possibilities for the transfer of marine sediment, the protection of the long-term existence of the sites of smaller service shipyards, the improvement of safety in shipping exit corridors and the definition of precise conditions for the management of marine waste (in particular ship-generated waste).

Based on the above, we can highlight the following key measures that have the following effects:

(a)

Direct transboundary impacts: The permanent existence of the separate navigation system and the measures for the coordinated implementation of all other nautical activities ensure the necessary standards for safe navigation in the Gulf of Trieste.

(b)

Indirect transboundary impacts: Measures to limit marine litter and measures for the controlled movement of marine sediments contribute to limiting the pollution potential of the wider area.

• Nature conservation

In the field of nature conservation (Figure 9), we have recorded a total of ten (

Table 6. Features of measures in the field of nature conservation (SI).

No.	Status	Content/Summary of the Provision (Current MSP)
		Spatial and management measures:
1	S3	In the navigation corridor from the port of Koper around Debeli Rtič, navigation is restricted for cargo ships and other vessels longer than 24 m within a distance of 400 metres from the coast.
2	S1	The boundary of the anchorage area for cargo ships along the coast of Debeli Rtič is additionally moved away from the boundary of the Debeli Rtič Landscape Park.
3	S3	Restrictions on navigation and moving of the boundary of the anchorage area are made in agreement with the Maritime Administration (for example, internal rules of the Maritime Administration).
4	S3	The area of the Dragonja River estuary is determined as an especially sensitive environment, and the conditions for nature conservation will be determined with an act (change in the Decree on Sečovlje Salina Nature Park is possible). In the area of the Dragonja River estuary, motor vessel navigation and anchoring are forbidden except for the needs of mariculture and the management of the Sečovlje Salina Nature Park.
5	S3	The area of the underwater sandbank on the western side of Punta and the ridge (step) on the eastern side are protected with an act or included in a new act on the protection of the Cape Madona Natural Monument. Proper management should be ensured.
6	S3	The protection area of Strunjan Landscape Park at sea should be extended.
7	S3	Fishing with bottom trawls is limited in the area of the detrital seabed near the tri-border with Italy and Croatia at sea. Only the use of a ‘volantina’ type bottom trawl is permitted. After the fishing exception period expires, the reasons for the foundation or insurance should be verified.
8	S6	Expert bases with regard to cross-border protection of the detrital seabed are prepared.
9	S6	Additional areas of sensitive habitat types, where anchoring is prohibited, should be identified.
10	S4	In the area of the expansion of the Natura 2000 site into the sea segment, coordination needs to be performed between the nature conservation sector and the sector of commercial and leisure fishing in terms of consensus on fishing.

) measures (the plan does not contain an explicit delimitation). Of the measures that have an equivalent in the previous state, only two are listed in the plan, namely a measure on the need for additional identification of sensitive habitat types and a measure on cross-sectoral coordination in the implementation of recreational fishing from the coast. All other measures are completely new and are aimed at improving the situation in the field of nature conservation. These include partial extensions of protected areas as well as the additional designation of already protected areas or the implementation of additional protection requirements when carrying out certain activities at sea and on the coast. This area also includes the transboundary protection of the seabed, which is a unique and direct initiative in the field of transboundary cooperation in the management of the marine environment.

Based on the above, we can highlight the following key measures that have the following effects:

(a)

Direct transboundary effects: Measures on fishing restrictions and joint protection of the detrital seabed at the three-country border (SI-IT-HR).

(b)

Indirect transboundary impacts: Virtually all other measures aimed at additional extensions of protection regimes have a positive impact on the wider area.

Based on the above, we can conclude that the new MSP, through a number of new provisions (measures as tools), builds on existing opportunities to achieve a good status of the marine environment, which is one of the main objectives of many international commitments and national environmental management strategies.

Table 7. Key elements: subjects of regulation, tools and outcomes in the case of MSP in Slovenia.

Spatial Planning and Management Tools
Fisheries	Maritime Transport	Nature Conservation
Main subjects of planning and management (regulation)
- fishing areas - fish species and quotas - fishing techniques and devices - fishing regime (spatial, seasonal and temporal) - fish stock protection regime - port infrastructure	- navigation, anchorage and mooring areas (location, extent) - regime of sailing and anchoring - areas and processes of relocation of marine sediment (location, extent, conditions)	- areas of protection regimes - areas of expansion of protection regimes - protective conditions for the implementation of individual activities and uses
	How to–which tools?
- provisions of the plan, which precisely determine the fishing areas (cartographic and textual) - provisions of the plan, which determine the conditions and method of fishing, quota limits, and requirements for the protection of fish stocks (textual) - provisions of the plan, which determine the conditions for handling marine waste (textual)	- provisions of the plan, which precisely determine the areas and regimes of navigation for individual types of vessels (cartographic and textual) - provisions of the plan, which precisely determine the areas, conditions and method of relocation of marine sediment (cartographic and textual)	- provisions of the plan, which precisely determine the areas where individual protection regimes apply (cartographic and textual) - provisions of the plan that specify special conditions or requirements for the implementation of individual activities and uses (textual)
	Outcomes/Efficiency
- control overfishing areas - control over the time regime - control over negative impacts on the environment (illegal fishing of species, waste management) - control over conflicts of interest (with other sectors)	- control over the use of space for maritime transport activities - control over the marine sediment relocation process - limiting maritime accidents - control over conflicts of interest (with other sectors)	- control over the use of space for nature conservation activities - protective control over the implementation of interests in space in the areas of other sectors

summarises the key elements that are subject to regulation with the above-mentioned tools. The table also defines the nominal effect as control over individual elements of regulation as introduced by the new plan.

All the above tools are provided in the plan in both textual and graphic form, and as such, are essentially representing a very precise set of spatial planning instruments. Compared to the situation before the plan existed, it is a comprehensive formalisation, both in terms of content and method, and thus also in the effect of regulating a single sectoral field. Such a relatively detailed conceptual design of the plan is, of course, possible in the Slovenian situation, where the spatial extent of the national sea and coast is relatively small.

4. Discussion

In a cross-border perspective, the two MSP create opportunities to coordinate development and conservation interests in the shared transboundary space. They introduce process instruments and implementation tools that complement existing practices or add innovations to maritime spatial planning. Process instruments mainly concern the methodology for the plan preparation (and cyclical amendments), through which cross-border environmental impacts, joint spatial development, or shared marine environmental management regimes can be planned and coordinated. Implementation tools set local, spatial, temporal and technical conditions for maritime activities. Similar observations on the contribution of new plans are noted by other studies [27,28,29,30], though research remains limited as these challenges are relatively new [31]. The real impact of the plans will only become clear over time [32,33].

The Italian MSP defines eight sectoral fields, the Slovenian one twelve. In the Gulf of Venice, three sectors are the most relevant: fisheries, maritime transport and nature conservation. For each sector, both plans include binding provisions with spatial and management measures. These cover implementation measures defining where, how and when a certain activity and land use can be carried out (e.g., S—spatial measures, T—temporal measures, TE—technical measures, etc.), as well as procedural, organisational and financial measures. Monitoring systems are set for each sector and the overall implementation of the plan. Measures have direct cross-border effects (e.g., traffic separation scheme, planned protection areas, etc.) and indirect ones (e.g., regulation of the disposal of marine waste, sustainable fishery management, etc.). The Italian plan is broader, offering greater scope for intersectoral and cross-border coordination. The Slovenian plan is more operational and binding.

4.1. The Added Value and Persisting Challenges of MSP for Italy

The development of MSP in Italy has significantly strengthened marine governance, particularly by coordinating institutions dealing with different maritime sectors. Managing these overlapping interests required strong horizontal and vertical coordination. To this end, an Interministerial Coordination Committee (TIC) was created under the Presidency of the Council of Ministers, to provide strategic direction while a Technical Committee—coordinated by the Competent Authority, the Ministry of Infrastructure and Transport—oversees plans’ preparation and implementation. This system represents a major achievement, conveying ministries responsible for different maritime affairs (Environment and Energy Security; Agriculture, Food Sovereignty and Forestry; Economic Development; Enterprise and Made in Italy; and Tourism). Vertical coordination was also ensured: all 15 coastal regions participated in the Technical Committee, identifying specific objectives, zoning, and regulatory measures for their territorial waters.

The drafting of the MSP coincided with the preparation of the National Maritime Strategy (Piano del Mare 2023–2025), previously absent in Italy. Though under different institutional mandates—Piano del Mare being approved by the Interministerial Committee on Sea Policies—the two are complementary and reinforce one another in supporting the sustainable blue economy.

The first version of the MSP remains limited in some respects, lacking a fully strategic, future-oriented vision, instead offering a snapshot of the current state of maritime space and activities. Still, they mark a crucial first step toward integrated ocean governance.

Although the zoning provisions do not, in principle, exclude any use—except in the case of Limited PUs and Reserved PUs assigned to a single use—the identification of priority uses in most PUs has initiated a dialogue on future developments, potentially leading to more detailed zoning in later cycles.

For the three key sectors examined, the MSP set commitments to expand understanding of sectoral activities and their pressures, coordinate the implementation of different policies, promote synergies between sectors, and support decarbonization.

A major shortcoming has been the absence of an early and inclusive consultation process. During the Strategic Environmental Assessment (SEA) phase, stakeholders and civil society raised strong concerns about this aspect. Yet, this gap also raised public awareness of the MSP process. Importantly, the plans now include a dedicated measure to enhance stakeholder engagement in implementation.

Finally, while the MSP provides tools to improve spatial management and governance, effective implementation will depend on sufficient financial support, human resource availability and political will.

4.2. The Added Value of Marine Spatial Planning for Slovenia

The adoption of Slovenia’s first MSP in 2021 marked a significant milestone in the evolution of national spatial governance and planning. For the first time, Slovenia established a formal instrument dedicated to the coordination and planning of maritime space, bridging the longstanding institutional and regulatory gap between land and sea governance.

Before the MSP, Slovenia did not possess a planning framework capable of comprehensively managing spatial interests at sea. Sectoral activities—such as fisheries, maritime transport, and nature protection—were regulated through individual development programmes at the state level. While some coordination occurred, it was often informal, fragmented, and reactive. Coastal land use, on the other hand, fell within the exclusive jurisdiction of municipalities, whose spatial plans addressed only terrestrial areas and were often based on outdated planning documents.

The MSP fundamentally restructured this system. As a hybrid instrument combining strategic and operational elements, the plan defines national spatial development objectives for the sea and introduces a set of spatial and management measures to implement them. These include clearly defined provisions for permitted uses, spatial regimes, development conditions, and activity-specific requirements. The MSP thus establishes a formal mechanism for cross-sectoral coordination—something that had previously been lacking—ensuring consistency and integration across diverse maritime interests.

Equally significant is the MSP’s alignment with existing land-based planning systems. It functions as an action programme for the implementation of Slovenia’s Spatial Development Strategy (SDSS) at sea and complements municipal planning at the coast. While municipalities retain competence over coastal land use, the MSP enables systemic coordination between national, regional, and local levels.

The MSP also reinforces Slovenia’s role in cross-border marine governance. For the first time, international and EU commitments—particularly in the areas of fisheries, marine environment protection, and nature conservation—are formally embedded in a binding spatial plan. The preparation of the MSP included the drafting of a Strategic Environmental Assessment (SEA), which systematically addressed potential transboundary impacts and ensured participation from neighbouring countries. This institutionalised approach to cross-border coordination strengthens regional cooperation in the Adriatic Sea and sets a foundation for joint initiatives, such as the designation of ecologically connected marine protected areas or the sustainable management of shared fish stocks.

The plan reflects EU-wide strategic goals while adapting them to the national context, thereby contributing to the development of a sustainable blue economy in Slovenia.

Despite its achievements, the effective implementation of the MSP remains a challenge. It requires sustained political commitment, adequate institutional capacities, and financial resources. Continuous stakeholder engagement—particularly with coastal communities and sectoral actors—is essential to ensure the plan’s long-term relevance and legitimacy.

• Comparative Overview: Added Value of MSP in Italy and Slovenia

1. Institutional Framework and Coordination Mechanisms

Italy has established a multi-level coordination system: an Interministerial Coordination Committee under the Presidency of the Council of Ministers provides strategic direction, while a Technical Committee led by the Ministry of Infrastructure and Transport involves key maritime ministries and 15 coastal regions. This ensures horizontal (inter-ministerial) and vertical (state–regional) coordination.

Slovenia, as a smaller and more centralised state, developed a hybrid instrument combining strategic and operational elements. MSP is led at the national level and formally links with municipal planning, especially for coastal areas. While it lacks equivalent structures to the Italian Committees, the Slovenian MSP ensures coordination through a systemic integration of sectoral and local levels.

Key distinction: Italy’s model relies on multi-level governance and institutional layering, while Slovenia’s model uses a unified planning instrument to align national strategy with both municipal and national implementation. Both models lay the groundwork for integrated sea space management, which must be continued and reinforced during MSP implementation.

2. Nature of the plan

Italy’s MSP integrates existing uses and organises their coexistence by zoning and prioritisation. The plans include some forward-looking elements that anticipate future developments in key maritime sectors. These strategic perspectives are, however, still at an early stage of operationalisation and will require further elaboration in subsequent MSP phases. Implementation will be essential in turning strategic perspectives into concrete actions, e.g., at the local level.

Slovenia’s MSP, in contrast, sets clear development priorities and incorporates spatial and management measures for their implementation. Closely tied to the Slovenian Spatial Development Strategy, it serves as a marine action programme with a strong strategic and regulatory basis from the start.

Key distinction: Slovenia emphasises immediate operational implementation, while Italy combines strategic foresight (expressed by strategic objectives) with a gradual approach to operationalisation, leaving room for future refinement and updates.

3. Sectoral Integration and Planning Tools

Both Italy and Slovenia use their MSPs to strengthen sectoral coordination, particularly for fisheries, maritime transport, and nature conservation.

Italian plans combine PU-based zoning (including related priority uses) with measures to spatially organise activities and promote coexistence. While providing a foundation for intersectoral dialogue and future strategic reflection, they lack specific regulatory mechanisms to resolve spatial conflicts or enforce sectoral priorities. This is due to the vastness and complexity of the geographic scope of the plans, and to their strategic nature. Conflict management and coordination measures, partly implemented through recently established cross-sector working tables (e.g., on fishery and nature protection within MSP), will need full operationalisation during the implementation phase.

In contrast, Slovenia’s MSP tightly combines strategic and operational elements. It defines legally binding spatial provisions and management measures for implementation, including use regimes, locational conditions, and activity-specific requirements. It integrates EU policy objectives across sectors and aligns with local spatial planning through coordination with municipal instruments.

Key distinction: Italy’s MSP establishes a zoning-based framework for sectoral integration and includes measures to strengthen coexistence and foster cross-sectoral dialogue, though its provisions remain largely non-binding. In contrast, Slovenia’s MSP provides a regulatory and enforceable set of integrated spatial management tools from the outset.

4. Cross-Border Dimension

Both Italy and Slovenia recognise the importance of cross-border coordination for shared marine resources and common EU and international commitments. However, neither has established a formal, long-lasting mechanism for cross-border MSP, yet. Exchange occurs mainly through sectoral actions—for example, in relation to infrastructure projects such as pipelines or terminals—or through project-based initiatives, e.g., on data and tools sharing. As part of their planning process, both countries conducted a Strategic Environmental Assessment (SEA) of their MSP. This represents an important formal step forward in addressing potential transboundary impacts. The SEA process provides a basis for transparency, enables notification of affected states, and opens the door to future coordination on regional maritime governance.

Key point: While no formalised cross-border MSP mechanisms have been established yet by either country, transboundary consultation was conducted in the frame of the SEA. In addition, projects provided the opportunity to collaborate on different MSP aspects. These seeds will need to blossom into lasting and concrete actions towards cross-border collaboration, starting with implementation.

5. Stakeholder Engagement

Both Italy and Slovenia have recognised the importance of stakeholder participation in MSP and have made some efforts to incorporate it in the planning process.

In Italy, stakeholder engagement took place during both knowledge-gathering and plan preparation, involving ministries, regional authorities, scientific institutions and some maritime stakeholders. Several stakeholders noted the need for earlier and throughout involvement, greater transparency, and more transboundary dialogue (Information taken from the results of the SEA process publicly available at https://www.sid.mit.gov.it/documenti-piano, accessed on 25 June 2025). The Italian MSP now includes measures to strengthen participation during the implementation phase, reflecting a commitment to a more inclusive planning culture. The effectiveness of this measure will depend on the actual availability of resources and expertise, as well as, in particular, on the empowerment of the participatory process.

Slovenia adopted a structured and integrated approach to stakeholder involvement. Public consultations were embedded in the SEA process, and various governmental and non-governmental stakeholders were engaged throughout the plan’s development. The small planning area and the centralised institutional structure facilitated a more direct and continuous dialogue between actors, contributing to the inclusiveness of the process.

Key distinction: Both countries recognised the importance of stakeholders’ engagement in MSP. Slovenia’s compact governance system allowed for closer integration of public input, while Italy has laid the groundwork for broader engagement during the implementation phase of MSP. Both countries should invest more in the transboundary dimension of stakeholder participation.

6. Implementation and Future Outlook

Italy and Slovenia have made initial strides in coordinated marine management with their first MSPs, despite differences in starting points, institutions, and planning cultures, which are also reflected in their implementation approaches.

The Italian MSP is a comprehensive first step toward integrated maritime governance. The plans have laid the foundations for implementation through PU-based zoning, spatial sectoral priorities, and targeted measures addressing key sectors. Developed alongside the Piano del Mare, the Italian MSP creates synergies with broader maritime policy. While primarily strategic, the plans were designed to initiate a long-term planning process with mechanisms for revision and adaptive management, allowing for progressive operationalisation in future cycles. Successful implementation of the Italian MSP depends on policy support, dedicated resources, and strengthened enabling factors, including enhanced data availability, improved stakeholder engagement, and reinforced institutional alignment.

Slovenia, by contrast, adopted a more immediately operational and binding model. Its MSP serves as both a strategic and implementation document, with enforceable spatial and management measures. Closely linked to national and municipal planning frameworks, it provides a legal basis for direct application. While enhancing regulatory clarity and integration, this approach also demands sustained capacity and financial resources for effective implementation.

Key distinction: Italy has adopted a progressive, stepwise approach prioritising coordination, strategic alignment, and long-term flexibility. Slovenia focuses on immediate regulatory applicability within a compact governance system. Both models reflect context-specific strengths and offer complementary lessons for the continued evolution of MSP in the Mediterranean region.

5. Conclusions

The development and adoption of MSP in Italy and Slovenia represent an important milestone in the evolution of maritime governance in the northern Adriatic. While their approaches differ in institutional structure, planning culture, and scope, both countries have made significant progress in establishing frameworks that support more coordinated, sustainable, and forward-looking use of marine space.

Italy has prioritised broad strategic coordination and long-term vision. Its MSP builds on a complex, multi-level governance system and serves as a dynamic foundation for future planning cycles. The identification of PU, priority uses, and sectoral measures provides an important platform for inter-sectoral dialogue and strategic foresight. The plan’s flexible design, supported by the parallel development of the Piano del Mare, allows Italy to adapt and refine its spatial governance tools over time—an approach well-suited to a large and diverse maritime territory.

Slovenia, operating within a more compact and centralised system, has developed a hybrid MSP that integrates strategic goals with operational measures from the outset. By linking the plan to existing spatial planning frameworks and establishing legal mechanisms for implementation, Slovenia has created a clear and actionable pathway for sustainable marine use. The plan’s structure supports immediate application, while also aligning with EU policy objectives and facilitating cross-border cooperation.

Both plans were prepared in line with the MSPD, including the implementation of Strategic Environmental Assessments, and both countries have shown a growing commitment to improving stakeholder engagement and cross-border dialogue. As the first generation of MSPs enters the implementation phase, the experiences of Italy and Slovenia offer valuable insights into the diversity of planning models and the importance of tailoring governance tools to national contexts.

Looking ahead, continued cooperation, mutual learning, and adaptive planning will be key to addressing shared challenges in the Northern Adriatic Sea. The work carried out by both countries lays a strong foundation not only for national development but also for deeper regional integration in marine spatial governance.