Search Results (46)

The sustainability of apiculture within Mediterranean forest ecosystems is contingent upon the extent and health of melliferous tree habitats. This study outlines a five-year initiative (2020–2024) aimed at mapping and monitoring four principal honey-producing tree species—pine (Pinus halepensis and Pinus nigra), Greek fir (Abies cephalonica), oak (Quercus ithaburensis subsp. macrolepis), and chestnut (Castanea sativa)—across Evia, Greece. This is achieved through the utilization of high-resolution Sentinel-2 satellite imagery in conjunction with a hierarchical deep learning framework. Distinct from prior vegetation mapping endeavors, this research introduces an innovative application of a hierarchical framework for species-level semantic segmentation of apicultural flora, employing a U-Net convolutional neural network to capture fine-scale spatial and temporal dynamics. The proposed framework first stratifies forests into broadleaf and coniferous types using Copernicus DLT data, and subsequently applies two specialized U-Net models trained on Sentinel-2 NDVI time series and DEM-derived topographic variables to (i) discriminate pine from fir within coniferous forests and (ii) distinguish oak from chestnut within broadleaf stands. This hierarchical decomposition reduces spectral confusion among structurally similar species and enables fine-scale semantic segmentation of apicultural flora. Our hierarchical framework achieves 92.1% overall accuracy, significantly outperforming traditional multiclass approaches (89.5%) and classical ML methods (76.9%). The results demonstrate the framework’s efficacy in accurately delineating species distributions, quantifying the ecological and economic impacts of the catastrophic 2021 forest fires, and projecting long-term habitat recovery trajectories. The integration of a novel hierarchical approach with Deep Learning-driven monitoring of climate- and disturbance-driven changes in honey-producing habitats marks a significant step towards more effective assessment and management of four major beekeeping tree species. These findings highlight the significance of such methodologies in guiding conservation, restoration, and adaptive management strategies, ultimately supporting resilient apiculture and safeguarding ecosystem services in fire-prone Mediterranean landscapes. Full article

Background/Objectives: This study aimed to assess the potential of sternal morphometric parameters derived from multidetector computed tomography (MDCT) for sex estimation in a contemporary Greek population. A secondary objective was to develop and evaluate statistical and machine learning models based on these measurements for forensic identification. Methods: Sternal measurements were obtained from chest MDCT scans of 100 Greek adults (50 males, 50 females). Morphometric variables included total sternum length, surface area, angle, and index (SL, SSA, SA, and SI); manubrium length, width, thickness, and index (MBL, MBW, MBT, and MBI); sternal body length, width, thickness, and index (SBL, SBW, SBT, and SBI); and xiphoid process length and thickness (XPL and XPT). Logistic regression and a Random Forest classifier were applied to assess the predictive accuracy of these parameters. Results: Both models showed high classification performance. Logistic regression identified MBL and SBL as the most predictive variables, yielding 91% overall accuracy, with 92% sensitivity and 90% specificity. The Random Forest model achieved comparable results (91% accuracy, 88% sensitivity, 93% specificity), ranking SSA as the most influential feature. Conclusions: MDCT-derived sternal morphometry provides a reliable, non-invasive method for sex estimation. Parameters such as MBL, SBL, and SSA demonstrate strong discriminatory power and support the development of population-specific standards for forensic applications. Full article

The aim of this study was to evaluate the suitability of eight softwood species most commonly used by Greek timber industries, including furniture manufacturers and companies producing roundwood, sawn timber, and plywood. The analysis was based on integrated Multi-Criteria Decision Analysis (MCDA), using a combined approach of the PROMETHEE method and the Analytical Hierarchy Process (AHP), taking into consideration some important criteria that affect timber quality. According to the PROMETHEE complete ranking, Aleppo pine (Pinus halepensis Mill.) achieved the best performance under the selected criteria among the examined softwood species, underlying the importance of Aleppo pine to the Greek timber industry. Our findings could be highly beneficial to the wood industry, promoting the recovery and advancement of the forest sector in general, taking into account that sustainable wood supply is lower than the total biomass available in Europe. Policymakers should prioritize the selection of conifer tree species that can strengthen Greece’s forestry sector, promote sustainable management practices, and increase the economic value derived from the country’s diverse forest resources. Full article

RSSI-based proximity positioning is a well-established technique for indoor localization, featuring simplicity and cost-effectiveness, requiring low-price and off-the-shelf hardware. However, it suffers from low accuracy (in NLOS traffic), noise, and multipath fading issues. In large complex spaces, such as museums, where heavy visitor traffic is expected to seriously impact the ability to maintain LOS, RSSI coupled with Bluetooth Low Energy (BLE) seems ideal in terms of market availability, cost-/energy-efficiency and scalability that affect competing technologies, provided it achieves adequate accuracy. Our work reports and discusses findings of a BLE/RSSI-based pilot, implemented at the Museum of Modern Greek Culture in Athens, involving eight buildings with 47 halls with diverse areas, shapes, and showcase layouts. Wearable visitor BLE beacons provided cell-level location determined by a prototype tool (VTT), integrating in its architecture different functionalities: raw RSSI data smoothing with Kalman filters, hybrid positioning provision, temporal methods for visitor cell prediction, spatial filtering, and prediction based on popular machine learning classifiers. Visitor movement modeling, based on critical parameters influencing signal measurements, provided scenarios mapped to popular behavioral models. One such model, “ant”, corresponding to relatively slow nomadic cell roaming, was selected for basic experimentation. Pilot implementation decisions and methods adopted at all layers of the VTT architecture followed the overall concept of simplicity, availability, and cost-efficiency, providing a maximum infrastructure cost of 8 Euro per m² covered. A total 15 methods/algorithms were evaluated against prediction accuracy across 20 RSSI datasets, incorporating diverse hall cell allocations and visitor movement patterns. RSSI data, temporal and spatial management with simple low-processing methods adopted, achieved a maximum prediction accuracy average of 81.53% across all datasets, while ML algorithms (Random Forest) achieved a maximum prediction accuracy average of 87.24%. Full article

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. Full article

Findings from monitoring Greek fir forests in central Greece regarding radial growth, insect infestations, plant communities, and climate response have highlighted the urgent need for expanded field research to address critical conservation challenges within the fir forest ecosystem on Giona and Parnassus mountains. This underscores the urgency of adopting measures to mitigate the impacts of both abiotic and biotic factors. Our findings so far, encompassing biometric data, tree ring analysis, observations on plant communities, climatic response, and insect infestations—primarily Choristoneura murinana (European Bud Moth)—across various stands on the mountain, have revealed significant local infestations of varying degrees. In many instances, these infestations were detected in adult trees, particularly in sunny areas or near country roads. Furthermore, our research has revealed the varied ability of the fir trees to adapt to both minor and significant climatic variations. The proposed research aims to monitor, preserve, and protect the fir trees, utilizing new knowledge for informed decision-making in their management. The project’s scope includes studying the growth characteristics of the fir forest, mitigating threats from biological factors (primarily the moth Choristoneura murinana-Lepidoptera, Tortricidae) by involving pheromones and other biological methods, promoting natural regeneration, preserving biodiversity, and evaluating the water status of the fir trees in response to climate change. Investigating their interactions and understanding the ecosystem’s status concerning the previously mentioned aspects is a significant priority for biological and genetic diversity, landscape aesthetics, recreation, and sustainable regional development (with economic impacts on local beekeepers and guesthouse owners). The evaluation of the implementation of the National Biodiversity Strategy in Greece has shown partial or minimal progress in addressing new threats and challenges, as well as in promoting new approaches. The proposed project, with specific actions, aligns with the spirit of the National Biodiversity Strategy and contributes to the strategy goals within the framework of conservation, restoration, and the strengthening of nationwide enhancement actions. Full article

Zelkova abelicea is an endemic tree growing only on eight mountain stands on the Greek island of Crete. The aim of this study was to determine the structure of the assemblages and analyze the diversity of the arachnid assemblages living on Zelkova abelicea, an endemic tree species in Crete. Material for the analyses was collected from tree trunks, oftentimes covered by bryophytes or lichens. In the examined material, 85 taxa were recorded. The most numerous groups represented in the analyzed material were Acari, including representatives of the orders Mesostigmata (78 ind. of 18 spp.) and Oribatida (1056 ind. of 51 spp.). In the order Mesostigmata the species represented by the highest numbers of specimens were Onchodellus karawaiewi (15 individuals) and Hypoaspisella sp. (13), which is probably a species new to science. In turn, representatives of the order Oribatida were much more numerous, with Zygoribatula exilis (284) and Eremaeus tuberosus (210) being identified in the largest numbers. Among the eight sampled localities, Gerakari (646 ind. and 50 spp.) and Omalos (409 ind. and 43 spp., respectively) had by far the richest assemblages. Statistical analyses confirmed the highly diverse character of the arachnid assemblages at the individual sites, which is a consequence not only of the varied numbers of arachnids found, but also of the presence of very rare species, such as Androlaelaps shealsi, Cosmolaelaps lutegiensis or Hoploseius oblongus. These results highlight the high species diversity of the arachnids found on Z. abelicea but also suggest the lack of connectivity between the isolated and fragmented forest stands on Crete. Full article

In recent years, we have witnessed a massive increase in the number of startups, which are also producing significant amounts of digital data. This poses a new challenge for expert analysts due to their limited attention spans and knowledge, also considering the low success rate of empirical startup evaluation. However, this new era also presents a great opportunity for the application of artificial intelligence (AI) towards intelligent startup investments. There are only a few works that have considered the potential of AI for startup recommendation, and they have not paid attention to the actual requirements of investors, also neglecting to investigate the desirability, feasibility, and value proposition of this venture. In this paper, we answer these questions by conducting a survey in collaboration with three major organizations of the Greek startup ecosystem. Furthermore, this paper also presents the design specifications for an AI-based decision support system for forecasting startup sustainability that is aligned with the requirements of expert analysts. Preliminary experiments with 44 Greek startups demonstrate Random Forest’s strong ability to predict sustainability scores. Full article

The Pinus halepensis (Aleppo pine) forests prevailing in the western part of the Mediterranean Basin are amongst the most severely affected by fire due to their inherent flammability. Our understanding of the environmental factors driving post-fire community dynamics is currently limited by the lack of time-series data at temporal scales. In this present study, we analyzed a chronosequence of Greek Aleppo pine forests spanning a post-fire period of 65 years. Our goal is to explore the role of post-fire age, altitude, exposure, slope level, parent-rock material, rock cover, and cover of evergreen sclerophyllous shrubs (maquis) on plant assemblage diversity (species richness and Menhinick’s diversity index) and composition. Post-fire age had a significant effect on taxonomic distinctness and community turnover but not on species richness. Taxonomic distinctness increased with post-fire age due to a higher prevalence of the families Fabaceae, Asteraceae, and Poaceae during the early post-fire period. Maquis cover was significantly associated with Menhinick’s diversity index, taxonomic distinctness, and community turnover. Exposure and slope influenced only Menhinick’s diversity index. The turnover in species composition was primarily driven by the geographical proximity of the forests and secondarily by post-fire age and the maquis cover. This highlights the importance of the initial floristic composition in the process of autosuccession after a fire in Mediterranean-climate ecosystems. Full article

This study concerns the design of a geocultural site in Huta Różaniecka. It is one of 166 sites prepared for the Kamienny Las na Roztoczu (Roztocze Stone Forest) Geopark project. The site is distinguished, on the one hand, by its interesting geology and geomorphology (exposures of Miocene sea shore with numerous fossils) and, on the other hand, by its quarries, stonemasonry traditions, and buildings (ruins of the Greek Catholic church). The aim of this paper is to present a model for building specialized documentation using a wide range of source materials, methods (field inventory, queries, interviews, high-precision Light Detection and Ranging-LiDAR measurements), tools (Leica ScanStation C10 laser scanner), and techniques (photography, Unmanned Aerial Vehicle-UAV, Terrestrial Laser Scanning-TLS). The applied research procedure model led to the construction of specialized documentation relating to the spatial dimension, natural features, and cultural context of the site. Taking into account the collected data, it should be concluded that the projected geocultural site at Huta Różaniecka, irrespective of the creation of a geopark, has great potential to build a tourist product that is attractive to a wide range of visitors. Full article

As an aesthetic resource in ancient China, the Zhuangzi’s description of Dao is similar to the American philosopher Emerson’s experience of beauty, and both reveal that the essence of beauty lies in its inherent vitality, spiritual transcendence, and the unity of multidimensional connotations. Emerson defines beauty as the constitution of all things in the world and believes it to be an expression of the universe. The Zhuangzi proposes the thought of tiandi damei 天地大美 (lit. Great Beauty of heaven and earth) as a manifestation of the function of the wordless Dao. Nature, intact from any human interference, becomes the common intermediary for Emerson and the Zhuangzi to elaborate on the connotations of beauty. The Emersonian definition of beauty originates from the philosophical implication of the world in ancient Greek, whereas the meaning of Great Beauty in the Zhuangzi, which embodies the worship of heaven in primitive religion, is very close to Emerson’s definition of beauty. The pattern of mei 美 consisting of da 大 (lit. great, equivalent to Dao) and yang 羊 (lit. auspice) signifies the natural celestial phenomena predicting good or bad luck and can be seen as synonymous with Dao illuminated by Daoism. By describing such natural imagery as forest, time sequence, dawn, and wilderness, Emerson reveals the vastness, harmony, brightness, and tranquility of beauty, which not only delights the spirit but also brings the human soul back to its natural state and improves personality. Emerson’s illumination of beauty conforms to those of Dao unraveled by the Zhuangzi. Despite the difference between the former’s poetic linguistic feature and the latter’s application of allegorical fables, both resort to visualized language to express internal aesthetic perceptions of the physical nature. Using the approaches of word tracing, textual comparison, and logical analysis, this article identifies the consistency in the original meanings of beauty in both Emerson’s essays and the Zhuangzi first and then goes on to analyze the similarities between their descriptions of natural imagery, so as to hint at the commonality in their understanding of natural beauty and verify the significance of literary language in cross-cultural comparative research. Full article

Greek fir (Abies cephalonica) seeds and cone scales were used, for the first time, for an analysis of their biologically active volatile compounds. It was observed that the yield of seed essential oil was 18%, which, among plants, is impressive. The seed essential oil was characterized by a distinctive forest scent with a subtle lemon undertone. The determination of the chemical compositions of the hydrodistilled oils isolated from the seeds and cone scales, achieved via chromatographic and spectroscopic methods (MS, NMR), revealed more than 100 compounds, mostly monoterpene hydrocarbons. The above methods allowed for the identification of 99.4% and 98.3% of the total seed and cone scale oil compositions, respectively. Limonene in its enantiomeric levorotatory form (S) constituted over 80% of the essential oil isolated from the Abies cephalonica seeds. This abundance of limonene makes them a potential natural source for obtaining this compound, which has demonstrated various biological properties. The main cone essential oil compounds were α- and β-pinenes as well as limonene. The cytotoxic effects of both essential oils were analyzed using the MTT assay in skin fibroblasts, keratinocytes, and melanoma cell lines, in the range of 0.012–0.2 μL/mL of essential oil. The cone scale essential oil was slightly more cytotoxic and induced a decrease in the cell viability in concentrations of 0.05–0.1 μL/mL, with small differences between the cell lines. The tested essential oils did not have selective effects on the melanoma cells (A375 and C32) when compared with normal cells. Both the seed and cone scale essential oils revealed good antimicrobial effects on Staphylococcus aureus and Escherichia coli. Full article

Farmland offers excellent conditions for developing solar energy while farmers seem to appreciate its notable revenues. The increasing adoption of photovoltaics (PVs) on farmland raises various concerns with the most important being the loss of productive farmland and the increased farmland prices, which may prevent young farmers from entering the farming occupation. The latter can threaten the future of agriculture in countries that are already facing the problem of rural population ageing. The aim of this paper is to examine the effect of crop type on farmers’ willingness to install photovoltaics on their farmland. To that end, this study applies four machine learning (ML) algorithms (categorical regression, decision trees and random forests, support vector machines) on a dataset obtained from a questionnaire survey on farmers in a Greek agricultural area. The results from the application of the algorithms allowed us to quantify and relate farmers’ willingness to invest in PVs with three major crop types (cotton, wheat, sunflower) which play a very important role in food security. Results also provide support for making policy interventions by defining the rate of productive farmland for photovoltaics and also for designing policies to support farmers to start and maintain farming operations. Full article

The active development of the problems related to the assessment of the role of the pedosphere in global climate change involves the possibility of application of the quantitative determination of soil organic carbon (SOC) as one of the indicators of a climatic response. Here, the authors have summarized the results of their own research over many years (1985–2023), comprising more than 500 determinations of SOC within the area of the Chernozem zone, in the south of the East European Plain (Moldova and Bessarabia, southern Ukraine, southwestern Russia), in the context of regional climate differentiation using evaluations of climatic energy consumption for soil formation. The data were structured for each of the regions through the creation of series of agrogenic soil transformations (virgin land, modern-day ploughed land (<100 years), continually ploughed land (>100 years), fallow land of the modern era (n·10 years), and post-antique long-term fallow land). It has been established, by means of statistical treatment of the data, that the intraregional differentiation of the bioclimatic conditions is the key factor determining the SOC content in the top horizon of soils in the south of the East European Plain. The comparison of the SOC content within the five variants of land use demonstrated that all the regions under study differed, with statistical significance only found in a single type of ‘continually ploughed land’ (>100 years). This fact reflects the leading role of the duration of agrarian loads in agropedogenesis. If the steppe Chernozems even 145 years ago had a SOC content of up to 4%, then the Chernozems in the forest-steppe zone, which used to have habitats with a SOC content of 4–7%, occupied the largest areas, and have now lost 30–40% of the original values in the 0–50 cm layer. Besides the rates of the SOC degradation, which are known and are comprehensively evaluated in the present work, the phenomenon of progradation was established in certain situations, in particular arising during the rotation regime of land use (from ploughing to fallow fields, and vice versa), which stimulated effective mechanisms of reproduction of organic substances. Thus, in one of the ancient agricultural regions, where in antiquity the land was cultivated by such ancient Greek states as Tauric Chersonesos and the European Bosporos in Crimea, post-antique long-term fallow lands possess higher SOC contents than their virgin analogues. It is not justified to consider virgin lands as absolute references for the evaluation of the humus conditions since the analysis of agrogenic series of Chernozems has corroborated an essential role of the soil organo-mineral matrix in the formation of the carbon protection capacity. Full article

The contribution of non-wood forest products is especially important in the context of rural sustainable development. Nevertheless, their perceived economic and environmental value remains low. The lack of an explicit and effective marketing strategy for NWFPs tailored to local mountain communities’ needs may lead to their restricted access to the market and underestimation of their value. The aim of this paper is to gain knowledge regarding the components of a marketing mix that could support the local markets of NWFPs, in Greek mountainous areas. The paper presents an analysis of the marketing mix for NWFPs, following for the first time the S.A.V.E. approach. The research contributes to the existing literature as we seek to “meet” groups of NWFPs’ consumers, in order to develop a customer-centric value proposition in Greek local mountain communities. The findings indicate that the marketing and promotion of NWFPs requires not only knowledge of the relative products and the market, it requires analysis and knowledge of the specific needs of local mountain communities and the ways that needs are met by the attributes and characteristics of the NWFPs as part of the solution that they can offer. Local mountain communities in Greece, through the exploitation of NWFPs, are trying to face challenges regarding the improvement of their income and their general wellbeing level. Also, we propose as a part of the marketing mix for NWFPs, their promotion as products with a distinct spatial, local identity, by associating them with local “culture economies”. Finally, we argue that a customer-centric marketing mix of NWFPs, which focuses on customers’ needs, desires, and resources as the starting point of the planning process, involves a higher level of mixing and synergies creation along the whole value chain, than simple personalization, with customers to interact with suppliers using ICT and by personal time disposition connected to nature. Full article