Anthropogenic Changes in a Mediterranean Coastal Wetland during the Last Century—The Case of Gialova Lagoon, Messinia, Greece

Abstract

Human interventions during the last 70 years have altered the characteristics of the Gialova Lagoon, a coastal wetland that is part of a wider Natura 2000 site. In this study, we explore how human interventions and climate altered the wetland’s hydrological conditions and habitats, leading to changing wetland functions over time. Our interpretations are based on a mixed methodological approach combining conceptual hydrologic models, analysis of aerial photographs, local knowledge, field observations, and GIS (Geographic Information System) analyses. The results show that the combined effects of human interventions and climate have led to increased salinity in the wetland over time. As a result, the fresh and brackish water marshes have gradually been turned into open water or replaced by halophytic vegetation with profound ecological implications. Furthermore, current human activities inside the Natura 2000 area and in the surrounding areas could further impact on the water quantity and quality in the wetland, and on its sensitive ecosystems. We suggest that a more holistic understanding of the broader socio-ecological system is needed to understand the dynamics of the wetland and to achieve sustainable long-term management and conservation strategies.

Understanding coastal wetland conditions and futures by closing their hydrologic balance: the case of the Gialova lagoon, Greece

“…1a). The main water body of the lagoon, on which this contribution focuses, covers an area of a 225.5 ha; an additional 85.2 ha is covered by surrounding wetland areas (Maneas et al, 2019). The spatial average of water depth in the main water body is approximately 0.6 m, with a range between 0.27 and 0.77 m (Dounas and Koutsoubas, 1996).…”

“…Mediterranean lagoons in particular are under pressure due to competing demands for water resources from agriculture, tourism, the fish industry and ecological systems relying on lagoons for their survival (Maneas et al, 2019;Perez-Ruzafa et al, 2011). While runoff is already decreasing in this region (e.g., Destouni and Prieto, 2018), climatic changes are expected to increase aridity by lowering the difference between precipitation and potential evapotranspiration by as much as 2-4 mm d −1 on an annual basis (Gao and Giorgi, 2008;Cheval et al, 2017).…”

“…While this approach is general, we focus its application on the Gialova lagoon (southwestern Peloponnese, Greece), the center of a Natura2000 protected area with a long history of water resource management that has radically altered the lagoon functioning (Maneas et al, 2019). This hydrologic system, characterized by unquantified point and diffuse water exchanges between lagoon and inland freshwater bodies, and between the lagoon and the Ionian Sea, offers an opportunity to apply the mass balance approach to estimate unknown hydrologic fluxes.…”

Data for wetlandscapes and their changes around the world

“…Through these functions, wetlands can support regional sustainability (Seifollahi-Aghmiuni et al, 2019) but are also one of the most vulnerable ecosystems globally (Golden et al, 2017). For instance, human land and/or water use developments (Destouni et al, 2013;Jaramillo and Destouni, 2015;Maneas et al, 2019) in combination with climate variability and change (Orth and Destouni, 2018;Seneviratne et al, 2006) affect large-scale water fluxes, with impacts on wetland functions and ecosystem services. These impacts extend over coupled systems of multiple wetlands and the associated total hydrological catchment that integrates these, referred to as a wetlandscape , with even well-intended actions towards various sustainable development goals potentially affecting wetland functions and services in different directions (Jaramillo et al, 2019).…”

Data for wetlandscapes and their changes around the world

“…Through these functions, wetlands can support regional sustainability (Seifollahi-Aghmiuni et al, 2019) but are also one of the most vulnerable ecosystems globally (Golden et al, 2017). For instance, human land and/or water use developments (Destouni et al, 2013;Jaramillo and Destouni, 2015;Maneas et al, 2019) in combination with climate variability and change (Orth and Destouni, 2018;Seneviratne et al, 2006) affect large-scale water fluxes with impacts on wetland functions and ecosystem services. These impacts extend over coupled systems of multiple wetlands and the associated total hydrological catchment that integrates these, referred to as a wetlandscape (Thorslund et al, 2017), with even wellintended actions towards various sustainable development goals potentially affecting wetland functions and services in different directions (Jaramillo et al, 2019).…”