Multi -actor labs (MALs), a form of real -world social experiments, were implemented in three coastal -rural regions in France (Charente River Basin), Spain (Mar Menor), and Greece (South-West Messinia) to better assess and tackle coastal -rural interactions that govern local sustainability challenges, such as water use conflicts and biodiversity degradation. The MALs used participative methodologies based on systems thinking and transition management. Stakeholders were continuously engaged in a series of workshops to co -produce knowledge, reach a common understanding of the sustainability challenges and issues at stake, and co -design solutions in the form of a roadmap for sustainable transitions in coastal -rural regions. This paper evaluates MALs to provide examples of successful sustainability transition experiments based on the outputs produced, outcomes achieved, and processes used in the three coastal, rural regions.

Agricultural land degradation is a global problem affecting food production and other ecosystem services worldwide such as water regulation. It is driven by unsustainable land use and management practices (e.g. intensive tillage, overuse of agrochemicals) and can be aggravated by future climate change. Land degradation is particularly problematic in arid and semi-arid areas of southern Europe, and distinct soil degradation processes impair agricultural areas in Portugal and Greece. This chapter aims to improve understanding of various degradation processes affecting agricultural land, including soil erosion, compaction, contamination, and salinity and sodicity. It summarises the scientific literature on the current status of these degradation processes in agricultural areas of Portugal and Greece and their main causes and consequences. Moreover, it provides examples of best management practices implemented to mitigate agricultural land degradation. Some degradation processes are relatively well documented (e.g. erosion), while knowledge of the spatial extent of others such as soil compaction is still limited. A better understanding of soil degradation processes and of the counter-impacts of improved agricultural management practices is critical to support decision-making and ensure long-term fertility and productivity, thereby maintaining the sustainability of agriculture.

The management of Natura 2000 sites is considered as the cornerstone for the conservation and restoration of biodiversity within Europe. However, protected ecosystems provide a plethora of benefits to local societies, and support the local economy. Thus, to seek solutions for complex environmental issues within Natura 2000 sties it is imperative to approach the site of concern as a connected social-ecological system, and to strengthen the participation of stakeholders in decision-making following a co-management approach.

Gialova Lagoon wetland, in Messinia, Greece represents an example of Natura 2000 site which needs to be managed. The overall aim of the PhD thesis was to assess the problem of lagoon salinization, and provide policy recommendations for wetland restoration and management of associated freshwater resources under a changing climate. The thesis has followed a social-ecological approach, by integrating DPSIR framework with participatory Systems Dynamic modelling and the concept of ecosystem services. Knowledge gaps about major social and ecological components were assessed by applying a variety of methods, namely (a) field monitoring and observations, (b) GIS analyses, (c) consultation with stakeholders, (d) modelling and scenarios.

The thesis results suggested that past human interventions had multi-fold effects on the Gialova Lagoon wetland, namely hydrology alteration, ecosystem fragmentation, loss and transformation of natural habitats. Furthermore, the combined effects of alterations in hydrology and climate change have led to increased salinity in the wetland over time. These alterations had profound implications on wetland ecosystem services such as the diversity of habitats and waterbirds and the provision of fish. Under contemporary hydrological connectivity and on-going climatic conditions, the mean annual salinity of the lagoon has increased from approximately 35 g/L during the period 2016-2018 to approximately 40 g/L during the period 2021-2023 indicating a salinization increase of approximately 1 g/L per year. 

To identify restoration alternatives, the work under the PhD thesis has engaged scientists with local stakeholders from the sectors of agriculture, fishing, tourism, and public administration, in a co-management approach. The end product, an SDM (Systems-Dynamics model) co-created with stakeholders, was suitable for exploring scenarios for salinity regulation and management of associated freshwater resources, under a changing climate (RCP 4.5). The derived management suggestions, namely restoration of the connectivity with the surrounding freshwater bodies (river, artesian springs) and between habitats (e.g., lagoon-marshes), could result in the de-salinization of the lagoon within a 10-year period, and could be applied within the Natura 2000 framework as they consider social and ecological needs (e.g. enhancement of biodiversity and fish production). However, under current abstraction rates for irrigation and municipal water-supply, there is a high risk of groundwater scarcity during years with dry conditions, and thus investments in water-saving technologies (e.g. smart irrigation) should be promoted to ensure adequate water availability for restoration, and enhanced resilience of the local economy against groundwater scarcity.

Assessments of ecosystem service and function losses of wetlandscapes (i.e., wetlands and their hydrological catchments) suffer from knowledge gaps regarding impacts of ongoing hydro-climatic change. This study investigates hydro-climatic changes during 1976–2015 in 25 wetlandscapes distributed across the world’s tropical, arid, temperate and cold climate zones. Results show that the wetlandscapes were subject to precipitation (P) and temperature (T) changes consistent with mean changes over the world’s land area. However, arid and cold wetlandscapes experienced higher T increases than their respective climate zone. Also, average P decreased in arid and cold wetlandscapes, contrarily to P of arid and cold climate zones, suggesting that these wetlandscapes are located in regions of elevated climate pressures. For most wetlandscapes with available runoff (R) data, the decreases were larger in R than in P, which was attributed to aggravation of climate change impacts by enhanced evapotranspiration losses, e.g. caused by land-use changes.

The Eastern Mediterranean is a highly populated area with air quality problems. It is also where climate change is already noticed by higher temperatures and s changing precipitation pattern. The anthropogenic aerosol affects health and changing concentrations and properties of the atmospheric aerosol affect radiation balance and clouds. Continuous long-term observations are essential in assessing the influence of anthropogenic aerosols on climate and health. We present six years of observations from Navarino Environmental Observatory (NEO), a new station located at the south west tip of Peloponnese, Greece. The two sites at NEO, were evaluated to show the influence of the local meteorology and to assess the general background aerosol possible. It was found that the background aerosol was originated from aged European aerosols and was strongly influenced by biomass burning, fossil fuel combustion, and industry. When subsiding into the boundary layer, local sources contributed in the air masses moving south. Mesoscale meteorology determined the diurnal variation of aerosol properties such as mass and number by means of typical sea breeze circulation, giving rise to pronounced morning and evening peaks in pollutant levels. While synoptic scale meteorology, mainly large-scale air mass transport and precipitation, strongly influenced the seasonality of the aerosol properties.

Five years after its establishment (2016), the LTER-Greece network outlines its vision, aims, objectives and its achievements through a series of case studies. The network consists of eight observatories, focusing on innovative research topics, aiming to be both cooperative and complementary, while currently being in the process of expanding. LTER-Greece acknowledges the complexity of ecosystems and the fact that effective management of natural resources may only be achieved by addressing every sector of a nexus system in order to understand inter-dependencies, thus accounting for solutions that promote resilience. Hence, LTER-Greece focuses on the holistic study of the water-environment-ecosystem-food-energy-society nexus, in order to face environmental and socio-ecological challenges at local and global scales, particularly climate change, biodiversity loss, pollution, natural disasters and unsustainable water and land management. Framed around five research pillars, monitoring and research targets nine research hypotheses related to climate change, environmental management, socio-ecology and economics, biodiversity and environmental process dynamics. As environmental monitoring and related research and conservation in Greece face critical shortcomings, LTER-Greece envisages confronting these gaps and contributing with interdisciplinary solutions to the current and upcoming complex environmental challenges.

Geography and associated hydrological, hydroclimate and land-use conditions and their changes determine the states and dynamics of wetlands and their ecosystem services. The influences of these controls are not limited to just the local scale of each individual wetland but extend over larger landscape areas that integrate multiple wetlands and their total hydrological catchment - the wetlandscape. However, the data and knowledge of conditions and changes over entire wetlandscapes are still scarce, limiting the capacity to accurately understand and manage critical wetland ecosystems and their services under global change. We present a new Wetlandscape Change Information Database (WetCID), consisting of geographic, hydrological, hydroclimate and land-use information and data for 27 wetlandscapes around the world. This combines survey-based local information with geographic shapefiles and gridded datasets of large-scale hydroclimate and land-use conditions and their changes over whole wetlandscapes. Temporally, WetCID contains 30-year time series of data for mean monthly precipitation and temperature and annual land-use conditions. The survey-based site information includes local knowledge on the wetlands, hydrology, hydroclimate and land uses within each wetlandscape and on the availability and accessibility of associated local data. This novel database (available through PANGAEA https://doi.org/10.1594/PANGAEA.907398; Ghajarnia et al., 2019) can support site assessments; cross-regional comparisons; and scenario analyses of the roles and impacts of land use, hydroclimatic and wetland conditions, and changes in whole-wetlandscape functions and ecosystem services.

Located at the south-western most part of the Balkan peninsula, along an important migration route (the Mediterranean/Black Sea Flyway), the Gialova Lagoon wetland is one of the few remaining Important Bird Areas (IBAs) along the south-west coast of Greece, also designated as a Special Protection Area. The wetland serves as the first suitable stopover for many spring migrants who have flown non-stop over the Mediterranean Sea, and the last before their journey back to Africa in the autumn. In this study, we conducted monthly field visits during the period October 2016 to January 2019 with the aim to complement existing information about the site, to evaluate the current status and distribution of waterbirds, to provide insights for the management of the area and to re-assess the IBA/Ramsar criteria. A total of 149 bird species representing 43 families and 15 orders were recorded, including 36 threatened species at an International, European or/and national level, and 40 species listed in the Annex I of the EUs Birds Directive (21 species were listed as both threatened and under Annex I). 81 species were identified as wetland related species, of which 66 species were identified as waterbirds (7 orders, 11 families). Waterbirds richness and abundance were higher during the Wet season and corresponding periods (Wintering and Spring migration). All parts of the wetland supported waterbirds and threatened species, with the S. Wetland sub-area being the most diverse during the Breeding/Nesting, and both migration periods. The abundance of most waterbirds and IBA species have declined over the last 20 years, but this does not necessarily mean that the area no longer fulfills Ramsar criterion 6 (and equivalent IBA criterion A4i). However, this outcome should not be overlooked by the site managers and conservation actions, such as the restoration of fresh water inflows which could improve habitats and water conditions for IUCN and IBA species, should be implemented with high priority. In addition, our results indicate that the area meets Ramsar criterion 4 and criterion 2, and thus we suggest that it should be further investigated and evaluated to potentially become the eleventh Greek Ramsar site.

Coastal wetlands and lagoons are under pressure due to competing demands for freshwater resources and climatic changes, which may increase salinity and cause a loss of ecological functions. These pressures are particularly high in Mediterranean regions with high evaporative demand compared to precipitation. To manage such wetlands and maximize their provision of ecosystem services, their hydrologic balance must be quantified. However, multiple channels, diffuse surface water exchanges, and diverse groundwater pathways complicate the quantification of different water balance components. To overcome this difficulty, we developed a mass balance approach based on coupled water and salt balance equations to estimate currently unknown water exchange fluxes through the Gialova lagoon, southwestern Peloponnese, Greece. Our approach facilitates quantification of both saline and freshwater exchange fluxes, using measured precipitation, water depth and salinity, and estimated evaporation rates over a study period of 2 years (2016-2017). While water exchanges were dominated by evaporation and saline water inputs from the sea during the summer, precipitation and freshwater inputs were more important during the winter. About 40 % and 60 % of the freshwater inputs were from precipitation and lateral freshwater flows, respectively. Approximately 70 % of the outputs was due to evaporation, with the remaining 30 % being water flow from the lagoon to the sea. Under future drier and warmer conditions, salinity in the lagoon is expected to increase, unless freshwater inputs are enhanced by restoring hydrologic connectivity between the lagoon and the surrounding freshwater bodies. This restoration strategy would be fundamental to stabilizing the current wide seasonal fluctuations in salinity and maintain ecosystem functionality but could be challenging to implement due to expected reductions in water availability in the freshwater bodies supporting the lagoon.

People perceive the importance of benefits from ecosystem services in different ways, depending on their values, beliefs, and needs. Acknowledging and integrating this diversity into decision-making processes can support informed natural resource management. Our empirical study unpicks the multiple ways stakeholder groups perceive the benefits derived from wetland ecosystem services (WES) in the area surrounding the “Gialova” coastal wetland in Messenia, Greece. The inhabitants from this region benefit from a range of WES, and most livelihoods are closely linked to agriculture and tourism. We aim to understand the patterns in commonly held stakeholder views on WES using “Q methodology”, a participatory mixed-methods approach. We identified five distinct perspectives on WES from a sample of 32 stakeholders. Alongside diverse perceptions of the relative importance of different WES, we observed a range of explanations of why certain WES are important and analyzed these through the lens of “value pluralism”. This identified tension between relational and instrumental values. Such analyses move beyond ecosystem service identification towards an understanding of value justifications and conflicts, and can support the deliberation of conflicted views, and policy design in alignment with people’s values.