Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleYalnız künye2026Topo-climatic control on earlywood and latewood growth of Pinus sylvestris L. across the Eastern Black Sea (Türkiye) climatic barrier
Işık, Fatih; Eraslan, Selim; Köse, Nesibe
This study investigates the growth dynamics of Pinus sylvestris across the Zigana and Tersun Mountains in the Eastern Black Sea transition zone (Türkiye), elucidating the role of topography in modulating climate–growth relationships. By utilizing 476 increment cores from 239 trees across 12 sites, we developed tree-ring width (TRW), earlywood (EW), and latewood (LW) chronologies to evaluate growth responses along elevation and aspect gradients using moving correlation analysis and Generalized Additive Mixed Models (GAMM). Results reveal a pronounced topo-climatic differentiation: northern slopes of Zigana operate under cold-limited regimes, where growth is primarily governed by early-season temperatures (March–April). Conversely, southern slopes and the inland Tersun Mountains exhibit a shift toward moisture-limited regimes, with growth showing high sensitivity to May–June precipitation. Moving correlation analyses demonstrate a significant temporal transition since the late 1960s, where temperature-driven growth stimulation has been progressively replaced by an intensifying sensitivity to early-season moisture availability. GAMM results revealed non-linear growth responses to seasonal temperature and precipitation variability. The response curves indicated reduced growth under colder March–April conditions, with relative growth increasing markedly when March–April mean temperatures exceeded a model-estimated threshold of approximately 2.0–2.2 °C. May temperature showed a narrow statistical optimum around 7.5–9.7 °C, above which the estimated growth response declined. May–June precipitation promoted growth up to a model-dependent saturation threshold of approximately 300 mm, followed by a tendency toward saturation or decrease. Ultimately, the Eastern Black Sea climatic barrier generates high local-scale variability, rendering inland populations increasingly vulnerable to drought stress under ongoing climate warming. These findings underscore the necessity of topographic context in climate-growth studies and emphasize the urgent need for site-specific, climate-adaptive forest management strategies.
- MakaleYalnız künye2026Multi-scale greening dynamics in Türkiye’s Ecoregions (2001–2024): the effects of elevation and land cover on NDVI change tendencies
Işık, Fatih; Eraslan, Selim
Understanding vegetation dynamics in terrestrial ecosystems is critical under the pressures of global climate change and anthropogenic activities. This study analyzes vegetation dynamics from 2001 to 2024 in Türkiye’s 13 biodiverse terrestrial ecoregions using a multi-scale approach, focusing not only on the main drivers, but also on the interactive and context-specific role of these factors. Using the Google Earth Engine (GEE) platform and MODIS Normalized Difference Vegetation Index (NDVI) data, integrated through a structured multi-scale framework, we applied statistical methods including the Mann–Kendall test, Kruskal–Wallis test, and LOESS curves optimized with leave-one-out cross-validation (LOOCV) to objectively model non-linear dynamics. The results revealed statistically significant positive NDVI change tendencies in all 13 terrestrial ecoregions (Mann–Kendall test, p < 0.05). Forest-dominated ecoregions exhibited the strongest greening, with Sen’s slope values reaching +0.0032 NDVI year⁻1 in the Euxine–Colchic Broadleaf Forests, whereas steppe ecosystems showed more moderate increases (e.g., Central Anatolian Steppe: + 0.0019 NDVI year⁻1). Across elevation gradients, the most consistent and strongest greening occurred at mid-elevations (500–1500 m; τ ≈ 0.40–0.65), while change tendencies weakened and became more heterogeneous at higher elevations. Land-cover-based analysis further showed that natural vegetation types exhibited the strongest nationwide tendencies (“Trees”: τ = 0.71; “Shrubland”: τ = 0.66), whereas anthropogenically influenced classes displayed weaker or regionally variable responses. Beyond documenting general greening patterns, the original contribution of this study lies in introducing a structured multi-scale framework that integrates long-term MODIS NDVI time series (2001–2024) with ecoregion, elevation, and land cover contexts. This approach enables the objective identification of ecosystem-specific and scale-dependent vegetation dynamics that cannot be captured by conventional single-scale or linear trend-based analyses commonly applied in previous studies in Türkiye.
- MakaleAçık Erişim2025Spatially explicit modeling of road icing susceptibility using GIS and a multi-criteria decision approach: A case study of Gümüşhane city (Türkiye)
Işık, Fatih; Kanyılmaz, Rabia; Çağlak, Savas; Eraslan, Selim; Zeybek, Halil İbrahim
This study develops and validates a GIS-based, spatio-temporal model to identify and prioritize road segments with high icing susceptibility in the Gümüşhane city center, Türkiye. Icing on urban roadways constitutes a significant threat to vehicular and pedestrian safety, particularly in regions characterized by complex topography and dense urban morphology. A Multi-Criteria Decision Analysis (MCDA) framework, employing the Analytic Hierarchy Process (AHP) with structured expert input, was used to synthesize ten primary causative factors. These include solar radiation, temperature, aspect, object height, precipitation, elevation, pavement material, slope, albedo, and road width — each representing a distinct topographic, climatic, or morphological influence on urban road icing. The AHP quantitatively established the relative influence of these factors, identifying solar radiation (28.5%), temperature (18.2%), and aspect (13.5%) as the most dominant drivers. The model generates monthly susceptibility maps that reveal "urban canyons"—narrow streets flanked by highrise buildings—consistently exhibit the highest and most persistent susceptibility due to severely limited solar radiation. The accuracy of the model's spatial predictions was quantitatively validated through field observations, with 91.4% of recurring icing locations correctly identified within high or very high susceptibility zones. This research culminates not only in a robust scientific framework but also in a validated decision-support tool that has been successfully integrated into the Gümüşhane City Information System (GCIS), where it is now operationally used to optimize winter maintenance strategies. Ultimately, this work provides a replicable, data-driven approach for enhancing urban resilience and traffic safety in challenging topographical settings.
- MakaleAçık Erişim2024Comparison with carbonate rocks hosted iron skarn in the eastern Sakarya Zone (Gümüşhane, NE Turkey): a geomorphologic, geochemical and stable isotopic approach
Sipahi, Ferkan; Zeybek, Halil İbrahim; Gücer, Mehmet Ali; Işık, Fatih
The carbonate rocks in the eastern part of NE Turkey are situated within the Pontide paleo-magmatic arc and are frequently in contact with granitoid formations, often hosting skarn mineralization in the region. These carbonate rocks, typically found on ridges and hillsides exhibit predominant orientations along east–west, northeast-southwest, and northwest-southeast directions. A part of limestone, named as biomicrite, metamorphosed and display a saccharoidal texture. Comprised mainly of calcite, with less secondary quartz and iron oxide minerals, these carbonate rocks are classified as Fe-poor calcio-carbonate and magnesio-carbonate, having higher CaO and LOI contents. Marble and recrystallized limestone with granoblastic texture mainly comprise of calcite, less quartz, magnetite, and hematite. Marble classification diagrams suggest calcic skarn mineralization, indicated by decreasing CaO (or CO2) and increasing MgO from limestone to marble (or skarn). Strontium contents deviate slightly from the lithosphere carbonate average, while low Rb contents, attributed to skarn metamorphism, indicate the absence of K-bearing minerals. The high Al2O3/SiO2 in the carbonate rocks can points out hydrothermal activity and carbonate disengagement can indicate to actualize at temperatures that can affect Ce and Al mobilities. The low authigenic U value, low U/Th and Ni/Co ratios in carbonate rocks have been implied that protolith constituents deposited under oxic conditions. Positive Eu anomalies in limestone and marble suggest the influence of hydrothermal fluids. Carbon and oxygen isotope values in marble are similar with those of metamorphic and skarn marbles, indicating a magmatic origin. Overall, mineralogical and geochemical analyses propose a uniform source and/or geological process for all studied marbles.
- MakaleAçık Erişim2024Elevation-dependent growth trends of Picea orientalis (L.) Peterm forests in the Fırtına Creek Basin (Rize/Turkey)
Işık, Fatih; Bahadır, Muhammet; Zeybek, Halil İbrahim; Hatipoğlu, İlter Kutlu
Changes in climatic conditions have ecological and economic consequences or impact for trees and forest stands. In this respect, it is crucial to understand the radial growth trends of trees, their ecological response across elevation gradients, and the possible impacts of climate change on the species. In this study, Picea orientalis (L.) Peterm, located in the Fırtına Creek Basin in the northern part of the Eastern Black Sea Mountains in northeastern Turkey, was investigated along different elevation gradients in the context of climate-growth response. In the study, six site chronologies along an elevation gradient from 900 m to 2050 m were developed. Dendroclimatological methods were applied to assess the elevation-dependent radial growth characteristics of trees. In total, 200 increment cores were collected from 98 living trees. The relationships between climate and tree ring growth along the elevation gradient showed a positive relationship between growth and temperature at upper elevations (1700–1900 m) and a positive relationship between growth and precipitation at middle elevations (1400–1600 m). In particular, January–April mean temperatures and May rainfall were positively correlated with tree-ring growth. At lower elevations (900–1100 m), the correlation coefficients between climate and growth are insignificant because, at these altitudes, the species have optimum ecological conditions. It was also found that mean temperatures between 0 °C and 2 °C in January–April and total precipitation between 60 and 100 mm in January–February positively affect tree growth. However, if these thresholds are exceeded, it is possible that growth may be adversely affected. This research underscores the complex interplay between climate variables and tree growth along elevation gradients, highlighting the need for adaptive management strategies in the face of changing climatic conditions.
- MakaleAçık Erişim2020Karadere Çayı Taşkını (Araklı -Trabzon)
Işık, Fatih; Zeybek, Halil İbrahim; Çağlak, Savaş; Bahadir, Muhammet
Taşkınlar ülkemizde son yıllarda değişen iklim şartları ile birlikte daha sık yaşanan doğal afetlerdir. Taşkınlara bağlı olarak birçok can ve mal kaybı yaşanmaktadır. Bu çalışmada taşkınların çok yaşandığı Doğu Karadeniz Bölümü’nde yer alan Trabzon’a bağlı Araklı ilçesinde 18 Haziran 2019 tarihinde meydana gelen taşkının coğrafi nedenleri incelenmiştir. Oluşan taşkın, Araklı ilçesine bağlı Çamlıktepe ve Yüceyurt mahallelerinde 10 kişinin yaşamını yitirmesine, çok sayıda meskenin de yıkılmasına sebep olmuştur. Taşkının yaşandığı Karadere Çayı havzasında yaşanması muhtemel taşkınların risk analizi yapılarak taşkına duyarlı alanlar belirlenmiştir. Çalışmada sahaya yönelik afet raporları, sayısal yükseklik, meteorolojik, akım ve jeolojik verilerden yararlanılmıştır. Çalışmada yöntem olarak Çok Kriterli Karar Verme yönteminin bir metodu olan Analitik Hiyerarşi Süreci kullanılmıştır. Taşkın duyarlılık analizi için mevcut yöntemlere farklı parametreler eklenerek oluşturulan üç ayrı teknik ile haritalar üretilmiştir. Analiz sonuçlarına göre, Karadere Çayı’nın bazı kıyı kesimleri, Haliloğlu ve Gülbekli derelerinin birleştiği yer ve Araklı şehir merkezi taşkına en duyarlı alanlar olarak tespit edilmiştir. Haliloğlu ve Gülbekli derelerinin birleştiği saha 18 Haziran 2019’da yaşanan taşkının ana merkezini oluşturmaktadır. Ayrıca sahada taşkınla birlikte yaşanan heyelan olayları da taşkının etki derecesini artırmış, çamur akıntısı oluşumuna neden olmuştur. Analiz sonuçları ve yaşananlar göstermektedir ki sahada bundan sonrada taşkın olasılığı yüksektir. Bu nedenle çalışmanın, yöneticiler ve karar vericiler tarafından muhtemel olumsuz sonuçların engellenmesi adına dikkate alınması beklenmektedir.