Stamatis Zogaris

Structural flood-control engineering can create negative impacts and societal conflict, yet few studies critically examine such projects while explicitly evaluating Nature-based Solutions (NbS) as alternative applications. This article presents a real Mediterranean case in which a large structural flood-control project was halted following ecological and legal scrutiny, creating an opportunity to reconsider flood management through an NbS framework. The study focuses on the Erasinos stream (Attica, Greece), where a government- and EU-funded flood-control project proposed extensive river channelization, flood-retention dams and other “hard” measures within and adjacent to a protected Natura 2000 area. Rather than proposing a detailed engineering redesign, our study compares two contrasting planning paradigms: the original engineering scheme, initiated in 2021, and a conceptual Nature-based Solutions (NbS) framework based on Natural Flood Management (NFM) and ecological restoration initiatives. The proposed NbS framework would substantially reduce structural river-training works while emphasizing distributed flood-water retention, restoration of river connectivity, floodplain reconnection and biodiversity enhancement. Such an approach has the potential to reduce flood risk while simultaneously enhancing biodiversity, cultural and protected-area values. The Erasinos case demonstrates that integrating ecological restoration, NbS and flood-risk management can shift peri-urban river planning away from rigid structural control toward a nature-positive management paradigm for Mediterranean catchments.

Understanding the extent to which marine connectivity can be predicted from shared oceanographic and biogeographic conditions remains a central challenge in marine ecology and evolution. Comparative analyses of sympatric species provide a powerful framework for testing whether common environmental contexts generate repeatable patterns of population structure and connectivity and if this also unfolds on a genomic level. Here, we investigated this question in the endemic Mediterranean clingfish genus Gouania , a group of cryptobenthic gravel-beach specialists with limited adult mobility and a short pelagic larval phase. We combined whole-genome resequencing of two sympatric eastern Mediterranean species ( G. orientalis and G. hofrichteri ) around Crete and Kythira with Lagrangian particle drift simulations, mitochondrial phylogeography across all five Gouania species and demographic reconstructions using MSMC2. Passive drift simulations predicted strong isolation of Kythira and restricted exchange between northern and southern Crete. These predictions closely matched genome-wide population structure in both species, revealing highly concordant patterns of connectivity despite independent evolutionary histories. Shared population contrasts were furthermore associated with a significant excess of parallel genomic divergence, with both genomic windows and candidate genes overlapping more frequently than expected by chance. Nevertheless, most differentiated genomic regions remained species-specific and functional enrichment analyses identified no dominant shared pathways, suggesting a largely polygenic basis of divergence. In contrast to the strong concordance observed for contemporary connectivity and genomic divergence, mitochondrial phylogeographic patterns and species-level demographic histories were considerably more heterogeneous across the genus. Together, our results demonstrate that the predictability of marine population structure is scale-dependent: shared seascapes can generate repeatable patterns of connectivity and partially parallel genomic divergence, whereas deeper phylogeographic and demographic histories remain strongly influenced by species-specific historical processes.

The distribution of Luciobarbus albanicus is almost completely restricted to the Ionian Freshwater Ecoregion of western Greece, and exhibits a marked north–south phylogeographic split. We examined 27 COI sequences (635 bp) from different populations in the northern (Kalamas, Louros, Arachthos) and southern (Acheloos, Trichonis, Pinios) sections of the ecoregion to see if these groups represent distinct species. Maximum Likelihood analysis recovered two well-supported clades that matched the geographic groups. However, the average K2P genetic distance between them was only 1.36%, while the distances within each group were substantially low, i.e., 0.02% for the northern and 0.07% for the southern populations. A detailed comparison of morphometric and meristic data, including the number of lateral-line scales, circumpeduncular scales, fin-ray counts, colour patterns, and lip shapes, revealed considerable overlaps, and no clear or consistent differences. Even though the mitochondrial divergence hints at some level of population structure, the lack of consistent morphological differences suggests that the northern and southern populations of L. albanicus are best considered conspecific.

Economidichthys mornosensis, a new species, is described from the Mornos River delta in southwestern Greece. It is related to Economidichthys pygmaeus, from which it is distinguished by having a large black blotch on the first dorsal fin in males, a short perianal organ, and a scaleless back along the complete base of the second dorsal fin. Molecular data suggest that the new species can be distinguished from E. pygmaeus by a minimum K2P distance of 5.7 % in the mtDNA COI barcode region. Economidichthys mornosensis is endemic to a very small area, and potentially Critically Endangered.

Aim: Using a widely distributed and frequently hybridising fish (genus Rutilus ) in the Palearctic as a model system, we re‐evaluated a series of hypotheses on phylogeny, taxonomy, phylogeography and the role of hybridization in evolutionary history based on the first large‐scale analyses of nuclear SNPs together with mtDNA data obtained from all Rutilus species. Location: Water systems in Northern Eurasia. Methods: Based on nuclear (ddRADseq) data, we applied phylogenomic, population genomic and introgression analyses to assess the diversity of lineages, their distribution and hybridization in the context of the hypotheses tested. Results: We identified 22 lineages in three major clades— Rutilus s. str., Leucos and Pararutilus . High diversity of lineages was discovered, with three revived species and three novel lineages of undescribed species in Europe. Evidence for extensive mito‐nuclear discordance and ongoing and past inter‐ and intrageneric introgressive hybridization was found in many lineages. A Caucasian relic lineage and the endangered narrow endemic species ‘ Rutilus ’ atropatenus were found to represent an independent lineage ( Orthroleucos ) with a high level of past introgression with Rutilus . Main Conclusions: The genetic structure of Rutilus revealed by nuclear SNPs contrasts markedly with that supported by mtDNA. Numerous mito‐nuclear discordances are evidence of the past secondary contacts and highlight the weakness of taxonomy based on mtDNA alone. A super‐lineage of mtDNA covering the range of many European, Siberian, Caucasian, and Central Asian Rutilus species (5000 km long) is a result of introgression of mtDNA from a widespread Ponto‐Caspian lineage whose distribution likely pulsed with Pleistocene glaciation cycles. Anadromous life histories may have evolved in parallel in different clades and been facilitated by hybridization. The high plasticity, adaptiveness and species diversity of the genus Rutilus may be underlined by their heterogeneous genomes resulting from extensive interspecific hybridization. However, narrow‐range endemic species may be threatened by introgressive hybridization.

Floating photovoltaic systems (FPV) are one of the emerging technologies that are able to support the “green” energy transition. In Greece, the environmental impact assessment of such projects is still under early development. The scope of the present study was to provide insights into the potential impacts of a small-scale FPV system on the water quality of the oligotrophic Kremasta Lake, an artificial reservoir. For this reason, a hydrodynamic and water quality model was employed. The results showed that the water quality parameter variations were insignificant and limited only in the immediate area of the FPV construction and gradually disappeared toward the shoreline. Likewise, this variation was restricted to the first few meters of depth of the water column and was eliminated onwards. The water temperature slightly decreased only in the area of close proximity to the installation. Average annual dissolved oxygen, chlorophyll-a, and nutrient concentrations were predicted not to change considerably after the panels’ construction. FPV systems can provide an attractive alternative for energy production in artificial reservoirs, especially in regions of land use conflicts that are associated with land allocation for alternative energy development. Given the limited data on the long-term impact of such projects, robust monitoring programs are essential. These initiatives rely on public support, making collaboration between stakeholders and the local community crucial.

This article explores the impacts of climate change on the rural and natural landscapes in the region of Eastern Macedonia and Thrace, northeastern Greece. The spatial distributions of the bioclimatic de Martonne Index and the phytoclimatic Emberger Index were calculated at a very high resolution (~500 m) for present conditions (1970–2000), two future time periods (2030–2060; 2070–2100), and two greenhouse gas concentration scenarios (RCP4.5; RCP8.5). The results show significant bioclimatic changes, especially in the Rhodope Mountain range and along almost the whole length of the Greek–Bulgarian border, where forests of high ecosystem value are located, together with the rural areas along the Evros river valley, as well as in the coastal zone of the Aegean Sea. The article describes the processes of bioclimatic changes that can significantly modify the study area’s landscapes. The study area reveals a shift toward xerothermic environments over time, with significant bioclimatic changes projected under the extreme RCP8.5 scenario. By 2100, de Martonne projections indicate that around 40% of agricultural areas in the eastern, southern, and western regions will face Mediterranean and semi-humid conditions, requiring supplemental irrigation for sustainability. The Emberger Index predicts that approximately 42% of natural and agricultural landscapes will experience sub-humid conditions with mild or cool winters. In comparison, 5% will face drier humid/sub-humid, warm winter conditions. These foreseen futures propose initial interpretations for key landscape conservation, natural capital, and ecosystem services management.

This article explores the impacts of climate change on the rural and natural landscapes at the Region of Eastern Macedonia and Thrace, Northeastern Greece. The spatial distributions of the bioclimatic de Martonne and phytoclimatic Emberger indices were calculated, at very high resolution (~500m), for the present conditions (1970–2000), two future time periods (2030–2060; 2070–2100) and for two greenhouse gas emission scenarios (RCP4.5; RCP8.5). The results show significant bioclimatic changes, especially in the Rhodope Mountain range and almost along the whole length of the Greek-Bulgarian border, where forests of high ecosystem value are located, together with the rural areas along the Evros river valley, as well as in the coastal zone of the Aegean Sea. The article describes the processes of bioclimatic changes that can significantly modify the landscapes of the study area. The study’s results reveal spatiotemporal shift towards more xerothermic environments under both scenarios. Independently of the employed indices, profound bioclimatic alterations are projected for the long-term timeframe of the extreme RCP8.5 scenario. According to the de Martonne outcomes, the more xerothermic Mediterranean and Semi-humid conditions are projected to impact the eastern, southern, and western agricultural landscapes (approximately 40% of the investigated area), the sustainability of which will depend on supplementary irrigation. Implementation of the Emberger index points out that by the year 2100, the natural and agricultural landscapes (distribution of ~ 42%) will be subjected to the Sub-humid, Mild winter, the Sub-humid, Cool winter (~33%) and the even more dry-thermal Humid/Sub-humid, Warm winter conditions (~5%). Based on these foreseen futures, initial interpretations for key landscape conservation, natural capital and ecosystem services management are proposed.

Fish sampling was conducted in 20 sites within the Ibër River and its tributaries in Kosovo (August 2023) collecting 23 taxa (1674 individuals) through a standardized electrofishing protocol. Relevant physico-chemical measurements and anthropogenic pressures were collected and analyzed with respect to the ichthyological data of the surveyed sites. The survey represents a rapid assessment procedure, limitations and prospects of the effort are described. Several attributes of the fish assemblages showed severe degradation, characterized by low population densities, low species diversity, minimal reproductive evidence and the absence of several sentinel species. Multiple anthropogenic pressures have severely modified the fish communities over a wide area; pollution, barriers to movement and hydroelectric dams stand out as important drivers of degradation. Only two fish species showed some level of tolerance to heavily polluted waters (Carassius gibellio, Rutilus rutilus). Low fish population densities were also correlated with various forms of hydromorphological degradation. Only Barbatula barbatula, Phoxinus sp. and Lepomis gibbosus had proportionately higher population densities in areas where impoundments and power-station dam hydropeaking were severe. In this regard, conservation actions are urgently needed.