Search Results (35)

The dispersion of microplastics in the sea is an emerging and crucial environmental problem. In this preliminary study, the hydrodynamics of microplastics transferred from flooded agricultural areas to the sea was assessed. The Daniel storm in 2023 in region of Thessaly, Greece, initiated the transfer of plastic debris via the Pinios River, which subsequently discharged to the coastal basin at the south area of Thermaikos Gulf (NW Aegean Sea). Field sampling and laboratory measurements of microplastics collected at the mouth of the Pinios were conducted. The dispersion of microplastics discharged by the Pinios River is subject to the dominant wind conditions over the area, which in turn determines the water circulation in the NW Aegean Sea. Thus, a hydrodynamic model was initially applied, followed by a transport model for the study of the dispersion of the microplastics. The models were applied for SW and NE winds and indicated that the majority of microplastics with a settling velocity 0.1 m/s accumulate in areas close to the river’s mouth or lateral coastal zones; however, under the influence of SW winds, minor quantities tend to reach the east coasts of the Thermaikos Gulf, while massive quantities are transported away from the river’s mouth in case of microplastics floating on the sea’s surface. Full article

This study examines the seasonality of Black Carbon (BC) and Brown Carbon (BrC) spectral absorption characteristics at a continental background site (Kozani) in southern Balkans (NW Greece). It aims to assess the seasonality and impact of different sources on light absorption properties, BC concentrations, and the fraction of BrC absorption. Moderate-to-low BC concentrations were observed, ranging from 0.05 µg m⁻³ to 2.44 µg m⁻³ on an hourly basis (annual mean: 0.44 ± 0.27 µg m⁻³; median: 0.39 µg m⁻³) with higher levels during winter (0.53 ± 0.33), reflecting enhanced emissions from residential wood burning (RWB) for heating purposes. Atmospheric conditions are mostly clean during spring (MAM) (BC: 0.34 µg m⁻³), associated with increased rainfall. BC components associated with fossil fuel combustion (BC_ff) and biomass burning (BC_bb), maximize in summer (0.36 µg m⁻³) and winter (0.28 µg m⁻³), respectively, while the absorption Ångstrôm exponent (AAE_370–880) values ranged from 1.09 to 1.93 on daily basis. The annual mean total absorption coefficient (b_abs,520) inferred by aethalometer (AE33) was 4.09 ± 2.65 Mm⁻¹ (median: 3.51 Mm⁻¹), peaking in winter (5.30 ± 3.35 Mm⁻¹). Furthermore, the contribution of BrC absorption at 370 nm, was also high in winter (36.7%), and lower during the rest of the year (17.3–29.8%). The measuring station is located at a rural background site 4 km outside Kozani City and is not directly affected by traffic and urban heating emissions. Therefore, the regional background atmosphere is composed of a significant fraction of carbonaceous aerosols from RWB in nearby villages, a characteristic feature of the Balkan’s rural environment. Emissions from the lignin-fired power plants, still operating in the region, have decreased during the last years and moderately affect the atmospheric conditions. Full article

In this study, C18-functionalized magnetic silica nanoparticles (Fe₃O₄@SiO₂@C18) were used as adsorbents for the magnetic solid-phase extraction (MSPE) of organic contaminants commonly applied to aquaculture water (organic booster biocides, herbicides, and insecticides) followed by Gas Chromatography coupled to Mass Spectrometry (GC–MS). The extraction conditions and efficiency of the nanoparticles for the determination of ten pesticides (atrazine, ethoxyquine, chlorothalonil, chlorpyriphos methyl, methyl parathion, chlorpyriphos, resmethrin, λ-cyhalothrin, permethrin, and irgarol) were thoroughly investigated. Several experimental parameters affecting the extraction efficiency such as the amount of sorbent, extraction time, and elution time were optimized by employing experimental designs as response surface methodology. Validation experiments showed that the average recoveries of target analytes were in the range of 60% to 99%. The optimized method exhibited good linearity (R² > 0.9901) and satisfactory precision (Relative Standard deviations, RSDs < 15%). The method detection limits ranged between 1.9 ng L⁻¹ and 62 ng L⁻¹. Finally, the MSPE method was successfully applied to aquaculture water samples collected from the Thesprotia region (N.W. Greece), Thermaikos Gulf (N. Greece) and Butrint (S.W. Albania). Full article

This study analyzes 1980–2020 landings data from three Mediterranean coastal lagoons—the Logarou and Rodia-Tsoukalio Lagoons (NW Greece) and the Mar Menor Lagoon (SE Spain)—to assess ecosystem changes and fishing pressure dynamics. The findings classify these systems as low-yielding, with productivity ranked as follows: Yield Logarou > Yield Rodia-Tsoukalio = Yield Mar Menor. Mean trophic level analysis (mTrL) revealed significant differences driven by the contribution of detritivorous and mid-level carnivorous species (TrL Mar Menor > TrL Rodia-Tsoukalio > TrL Logarou). The fishing pressure indices suggest reduced fishing intensity in the Greek lagoons, while in Mar Menor, a stable Fisheries in Balance (FiB) trend corresponded with stable yields despite eutrophication. Cluster analysis (CA) and principal component analysis (PCA) linked ecosystem differences to sediment characteristics and changes in habitat structure. These results underscore a transition of Mediterranean coastal lagoons toward new ecological states, highlighting the urgent need for habitat conservation and adaptive management strategies to ensure sustainable fisheries under increasing environmental pressures. These findings may be extrapolated to similar transitional coastal ecosystems facing comparable anthropogenic stressors worldwide, providing a broader framework for understanding and managing lagoon systems under changing environmental conditions. Full article

The accuracy of the Weather Research and Forecasting (WRF) model’s predictions for air temperature and precipitation in northwestern Greece varies under different weather conditions. However, there is a lack of understanding regarding how well the model performs for specific Weather Types (WTs), especially in regions with a complex topography like NW Greece. This study evaluates the WRF model’s ability to predict 2 m air temperature and precipitation for 10 objectively defined WTs. Forecasts are validated against observations from the station network of the National Observatory of Athens, focusing on biases and skill variation across WTs. The results indicate that anticyclonic WTs lead to a significant overestimation of early morning air temperatures, especially for inland stations. The precipitation forecast skill varies depending on the threshold and characteristics of each WT, showing optimal results for WTs where precipitation is associated with a combination of depression activity, and orographic effects. These findings indicate the need for adjustments based on WT in operational forecasting systems for regions with similar topographical complexities. Full article

This study aimed to assess the contribution of leadership to Total Quality Management (TQM) implementation in secondary education and to determine the extent of TQM practices, as perceived by teachers, within the Ioannina region, NW Greece. The study also explored how these perceptions relate to various variables. A quantitative approach was employed, involving 128 teachers from secondary education schools in the Ioannina region, NW Greece. The findings illuminate the profound influence of leadership on successful TQM implementation. Effective leaders foster a climate of collaboration, provide resources, and encourage teamwork, ultimately contributing to the enhancement of teaching and learning quality. Moreover, this research study underscores the compatibility of the TQM and EFQM principles in promoting quality enhancement within educational settings. The EFQM Leadership score was calculated by averaging the ratings of leadership behaviors like collaboration, communication, and decision making. The results reveal a strong commitment to TQM principles, with overall TQM and EFQM Leadership scores of 3.58 (±0.11) and 3.46 (±0.30), respectively. The EFQM Leadership dimensions demonstrated significant alignment, particularly in areas such as teacher participation and communication of quality standards. However, there is room for improvement in encouraging two-way communication and ensuring consistent leadership decision implementation. This study highlights the crucial role of effective leadership in fostering a culture of quality and excellence in secondary education, emphasizing the importance of collaboration, communication, and alignment with EFQM principles for successful TQM implementation. Full article

This paper discusses the evolution of human settlement in ancient Macedonia from the Neolithic to the Late Roman periods, based on the results of a new multi-disciplinary and multi-scale archaeological survey in northern Grevena (NW Greece). Building upon an unpublished (legacy) survey, we developed a GIS-structured workflow that integrates site-revisiting and surveying strategies (material collection and test pits) with multi-temporal remote-sensing analyses, offering analytical information about site distribution, characterisation, dating, and taphonomy. Notably, the new study led to a 64% increase in the number of known sites. The combined results indicate that prehistory is less represented in the surface record than historical periods, likely due to the impact of soil erosion episodes. The Late Bronze Age and Early Iron Age saw increased site numbers and the emergence of a settlement structure that characterised the area until the Hellenistic period. During the Roman period, the pattern shifted from a seemingly limited use of the landscape towards a model of more extensive habitation. This was driven by the appearance of new rural sites that introduced a land-use regime designed to support agricultural intensification by implementing anti-erosion measures, such as field terraces. Full article

Microtus thomasi (Rodentia: Arvicolinae), a fossorial vole endemic to the SW Balkans, uses a variety of substrates but its underground behavior remains poorly understood. This study examines the architecture and utilization of M. thomasi burrow systems in NW Peloponnese, Greece. In particular, eight burrow systems were meticulously excavated and studied, with comprehensive measurements taken of key characteristics, including length, depth, soil mounds, and surface openings. Key coordinates were recorded using a differential GPS device for detailed mapping and fractal dimension analysis using the box-counting method was employed to assess burrow system complexity. Soil samples were analyzed for particle size and chemical composition, and vegetation types at each site were identified. We did not find statistically significant correlations between size and complexity of the burrow systems and soil composition, altitude, or specific soil components. On the other hand, we did observe statistically significant differences in tunnel diameter between two burrow systems and in tunnel depth between more. Moreover, our study showed that more than one same-sex individual can occupy a single burrow system and not just an adult male-female pair, that was previously recorded, indicating the need for further study of the social behavior of this vole species. This study provides valuable insights into the underground behavior of M. thomasi by providing information on the features of its burrow systems, thus contributing to our understanding of its biology. Full article

In open pit mining areas, knowledge of geotechnical conditions (e.g., overburden thickness, background slope, and fault locations) ensures geotechnical safety during exploitation as well as reclamation planning. The Greek Public Power Corporation initiated a research program after stability issues emerged on the southern side of the Mavropigi open pit mine in NW Macedonia. Geotechnical wells revealed steeply dipping bedrock and thin tectonic contact, indicating the need for the detailed imaging of the subsurface for future stability measures. For this purpose, a geophysical investigation aimed to extract information mostly for the dip of the interface between schist bedrock and overlaying Neogene sediments and/or limestones. Based on the high contrast of electrical properties between schists and limestones, as well as the differences in acoustic impedance and formation thickness, the seismic reflection and electrical resistivity tomography (ERT) methods were selected. The suitability of the seismic reflection for its application in this area was checked by generating synthetic seismic data, which resulted from the simulation of seismic wave propagation for geological models of the area. The acquisition parameters were determined after the noise test. Field seismic data processing produced a depth-migrated section, which revealed the existence of a fault. The use of dipole–dipole and gradient arrays, in 2D and 3D electrical resistivity measurements, ensured both the lateral and vertical mapping of schist bedrock and detected limestone bodies within the overburden. Also, the tectonic contact zone between limestone and schist formations was properly imaged. The comparison between geoelectrical and seismic sections indicated that the seismic reflection method provided a more accurate estimate of fault inclination. Finally, the geophysical survey enriched the geotechnical models necessary for sustainable mining (e.g., rational exploitation, the optimization of productivity, and zero accidents) including the planning of future reclamation. Full article

The WRF model temperature and precipitation forecast skill for the area of northwestern Greece is examined separately for each of the 10 objectively defined Weather Types (WTs). The WTs are defined for the 10-year period: 1 January 2009–31 December 2018. Their definition is achieved with the application of k-means Cluster Analysis on ERA5 meteorological data. The WRF model is applied in three domains (Europe—Greece—NW Greece) using the one-way nesting technique in a spatial resolution of 18, 6 and 2 km. Specifically, the model runs for 64 days (10% of the number of days attributed to the WT with the highest number of days) with the lowest distances from each WT’s cluster center. The WRF forecast data of 2 m air temperature and precipitation are compared with the available meteorological observations operated by the METEO unit at the National Observatory of Athens. The validation of 2 m air temperature is performed for 04UTC and 12UTC for the first and second days of forecast using the Cressman method, separately for each meteorological station and WT. The validation of precipitation is performed for daily accumulated values for the first and second days of forecast, using forecast data from the 3 × 3 = 9 surrounding grid points of each meteorological station and calculating categorical statistics based on contingency tables for each WT and for different thresholds. According to the results, there is a remarkable overestimation of 04UTC air temperature for the anticyclonic WTs, especially for the inland stations, while the precipitation forecast skill generally depends on the threshold and the WT characteristics. Full article

Greece was hit by an extreme heat wave, with a significant impact on human health and natural ecosystems in the period between 28 July and 11 August 2021. After the end of this unusual warm period, a rare occasion of multiple supercell storms was observed on 11 August 2021 in northern and central Greece. The synoptic conditions indicated embedded short waves in a northwesterly flow and significant thermal instability across the regions of interest was evident. In conjunction with the strong vertical wind, shear organized convection was released. At least six long-track supercells were documented and the onset, evolution and specific characteristics of them are presented. All supercells moved from NW toward SE, accompanied by large hail, intense rainfall and destructive wind gusts, producing widespread damage along their track. Full article

The dependence of the atmospheric pollution levels on the synoptic conditions and the associated prevailing weather regimes over Ioannina was examined for the 3-year period of 15 February 2019–14 February 2022. The study period is constrained by the availability of quality local air (particulate and gaseous) pollution measurements. The data used consist of (1) daily grid point values of the main meteorological parameters over the geographical domains of southeastern Europe and the greater Epirus region, obtained from ERA5 Reanalysis database and (2) hourly values of the main meteorological parameters and the concentration of basic pollutants recorded at the automatic environmental station of the Epirus Region located at the center of Ioannina. At first, 12 Weather Types (WTs) were defined on daily basis by applying a multivariate statistical methodology including Factor Analysis and k-means Cluster Analysis of the meteorological data. Next, for each WT, the average values, the standard deviations and the mean diurnal variations in the pollutant concentrations were calculated. According to the results, it appears that almost all pollutant concentrations were considerably higher during two anticyclonic WTs prevailing in the cold period of the year, while the diurnal variations in the concentrations were affected by the diurnal variations in traffic, combustion processes and solar radiation. The exact influence of the above factors depends on the characteristics of the prevailing WT. Full article

The evaluation of weather forecast accuracy is of major interest in decision making in almost every sector of the economy and in civil protection. To this, a detailed assessment of Bologna Limited-Area Model (BOLAM) seven days fine grid 3 h predictions is made for precipitation, air temperature, relative humidity, and wind speed over a large lowland agricultural area of a Mediterranean-type climate, characterized by hot summers and rainy moderate winters (plain of Arta, NW Greece). Timeseries that cover a four-year period (2016–2019) from seven agro-meteorological stations located at the study area are used to run a range of contingency and accuracy measures as well as Taylor diagrams, and the results are thoroughly discussed. The overall results showed that the model failed to comply with the precipitation regime throughout the study area, while the results were mediocre for wind speed. Considering relative humidity, the results revealed acceptable performance and good correlation between the model output and the observed values, for the early days of forecast. Only in air temperature, the forecasts exhibited very good performance. Discussion is made on the ability of the model to predict major rainfall events and to estimate water budget components as rainfall and reference evapotranspiration. The need for skilled weather forecasts from improved versions of the examined model that may incorporate post-processing techniques to improve predictions or from other forecasting services is underlined. Full article

In the last decades, Primula veris subsp. veris (roots and flowers) has been over harvested through legal and illegal ways in Greece, due to its extremely high commercial demand, as it is used in industry because of its well-known therapeutic properties. As ex situ cultures of the plant have been already developed, in the current comparative study, the herbal teas (infusions) from both flowers of cowslip growing wild in the Prespa Lake Park (NW Greece), and from ex situ propagated and cultivated plant material, have been investigated, with the ultimate goal of assessing them qualitatively. Furthermore, through classic phytochemical studies, the ten most abundant metabolites, belonging to the chemical categories of flavonol-glycosides and methoxy flavones, have been identified and structurally determined. The chemical profile of both infusions has been further analyzed through UHPLC-HRMS, showing that they show only light differences. The total phenolic content (TPC) of both studied samples (wild and ex situ cultivation), was determined by the Folin–Ciocalteau method, followed by an antioxidant activity assay though DPPH where, in both cases, wild plants exerted higher phenolic load and stronger antioxidative properties. According to the reported results, it could be proposed that the ex situ cultivated plant material could facilitate the mass production of plants and the sustainable cultivation of cowslip in the Greek mountains. Full article

The present study examines the imprint of salt tectonics on carbonate depositional patterns of the Ionian zone platform edge to slope transition. The study area is part of an overturned rim syncline adjacent to a salt diapir. The Ionian zone is made up of three distinct stratigraphic sequences (pre-, syn- and post-rift sequences) represented by evaporites and shallow water carbonates at the base that pass gradually to a sequence consisting of pelagic limestones with shale intervals. In the study area, six cross sections were constructed, mainly covering the edge-to-slope overturned succession of Early Cretaceous to Eocene carbonates (post-rift stage) in the northern limb of the syncline. In the measured sections, abrupt changes in sediment texture resulted in the formation of distinct, thick-bedded carbonate layers, identified as packstones to grainstones–floatstones, with abundant fossil fragments, indicating deposition by debrites in a platform slope or slope-toe environment. Planar and ripple cross-lamination also suggest the involvement of turbidity currents in the depositional process. In the upper levels of the Lower Cretaceous carbonates, chert bodies with irregular shapes indicate soft sediment deformation due to instability of the slope triggered by salt intrusion. Internal unconformities identified in the field and in the available seismic data combined with the vertical to overturned dipping of the strata correspond to a basal megaflap configuration. Syn-sedimentary deformation resulted in the accumulation of debritic and turbiditic layers, while the compressional regime established in the area from the Late Cretaceous to Early Eocene enhanced the fracture porosity of carbonates, which could eventually affect the reservoir properties. Full article