Studia Quaternaria

In recent years, the impacts of natural disasters on rural areas, urban settings, farmlands, transportation systems, and constructed infrastructures have received considerable focus. This study began with recognizing natural hazards by evaluating available data and conducting field research. Following that, a risk layer was created by superimposing environmental elements that affect the likelihood of risks, including geological features and landform types, which were analyzed through geomorphon techniques. The research also measured the probability of risk occurrence across various categories of independent variables. Results indicate that geological and topographical elements are vital in influencing the types of natural hazards within the Arangeh catchment. In particular, rock formations such as conglomerate, green tuff, sand, shale, and young alluvium found in young terraces exhibit the highest potential for hazards. The likelihood and variety of hazards amplify when these lithological units are located on elevated and steep landscapes. Additionally, the presence of faults significantly influences hazards associated with mass movements, including rock falls. The widest range of hazards within the Arangeh catchment can be found in slope, hollow, and valley landforms. To prevent an increase in risks, it is essential to avoid expanding settlements in these areas designated for garden purposes.

The Kremenets Mountains are among the characteristic areas of the Podolian Upland (Ukraine), which remains insufficiently studied. The study area was characterised using the main methods of automatic classification of landforms, namely the geomorphon method and the topographic position index (TPI). The obtained results were correlated with the geological maps of a bedrock and superficial Quaternary sediments, scale 1:200,000, to identify relief types within the Kremenets Mountains. The main types of relief of the Kremenets Mountains were categorised, and their regionalisation was carried out according to the reference landforms. Structural and denudational, denudational and fluvial types of relief were identified. Gravitational, karst, biogenic and technogenic landforms were also specified, including a field research. Morphometric maps of the study territory were constructed, and its main indicators were characterised according to equal-sized (1×1 km) squares, namely slope gradient, vertical and horizontal relief dissection. Analysis of these maps allowed us to identify regions with high, mean and minimum values of indices, which formed the foundations for separation of the geomorphological subregions within the Kremenets Mountains, namely Kremenets steeply sloping highly dissected subdistrict, Zalistsi moderately sloping meanly dissected subdistrict, and Kutianka gently sloping slightly dissected subdistrict.

Morocco, like many countries in arid zones, is faced with desertification, particularly in the south and southeast. Shifting dune sand is a key indicator of this phenomenon. The study of aeolian dynamics in the Merzouga-Tafilalet region aims to understand desertification processes, from rock erosion to sediment transport and deposition. A mineralogical and granulometric analysis of dune sand was carried out to determine their composition and origin. The study was based on petrographic examination and identification of the transport mechanisms involved. The sandy deposits are predominantly composed of quartz, with the presence of oxides, heavy minerals, feldspars, micas and calcite. These elements originate from the crystalline formations of the Anti-Atlas and are transported by aeolian and hydrological processes. Analysis of the quartz grains reveals different morphologies, reflecting the history of their transport and deposition. Aeolian dynamics have led to the formation of distinct granulometric fractions, each corresponding to a specific aeolian period. The mixing of these fractions results from the alternation of strong and weak wind regimes, as well as stabilization phases linked to wind degeneration. This study provides a better understanding of the evolution of dune sand in the face of environmental change.

This study aims to investigate the effects of acidic phosphate solution (PS) from phosphogypsum collected from the Tunisian Chemical Group in Gabes, with a pH of 2.6, on the physico-chemical and mechanical properties of Tunisian clay soils, Aleg (AG) and El Haria (EH). Here, the feasibility of employing these soils as natural impermeable barriers for phosphogypsum (PG) disposal sites has been explored. Mineralogical and chemical compositions of raw and modified clays were identified using XRD and XRF. The contact effect of phosphoric aqueous waste in comparison to tap water on raw clays, was revealed by a clear disappearance of the carbonate peak. The drained shear strength of Aleg soil decreased to 48 kPa. Conversely, the cohesion of El Haria soil increased with phosphate solution. Triaxial test results showed c’ and φ’ decreased to 44 kPa and 21° for AG and increased to 155 kPa and 27° for EH. AG and EH clays showed an important support capacity that reached 38 m and 57 m, respectively.

The ostracod fossils are extremely important for the reconstruction of the prehistoric environment. This is also the case for lake environments (pH, carbonate content, isotope geochemistry, water depth, temperature, vegetation cover). In a lake of hydrothermal origin, such as Lake Peţea in the north-western part of Romania, it is of particular importance, as the lake has now dried up and a significant part of the endemic fauna has disappeared. The conclusions drawn from the Ostracoda remains, together with other taxa, could be of great help to local conservation efforts to restore the lake to its former state. Based on our results the following taxa were identified in the Early Holocene deposits of the lake: Candona weltneri var. obtusa, Pseudocandona rostrata, Cypridopsis vidua.

This study aims to assess the impact of climate change on vegetation and water resources in the Safsaf watershed of northeastern Algeria. Landsat satellite imagery from 2012 to 2022 was analysed to compute the Normalized Difference Vegetation Index (NDVI). MODIS and CHIRPS data were processed in Google Earth Engine (GEE) to explore relationships between NDVI, land surface temperature (LST), and precipitation. The analysis revealed a significant decline in water surfaces and vegetation cover, associated with increased human activities and rapid urbanisation driven by population growth. Pearson correlation showed a moderate negative relationship between NDVI and LST, and a weak negative correlation between the Normalized Difference Water Index (NDWI) and precipitation. These findings indicate the need for integrated environmental management strategies to mitigate climate change impacts and prevent further degradation of the Safsaf watershed, emphasising the importance of incorporating ecological and hydrological considerations into future planning.

Africa is the continent most exposed to fires, accounting for over half of the burned areas and pyrogenic greenhouse gas emissions globally. Fire seasonality in Africa follows the dry seasons, primarily from October to March for the Northern Hemisphere, with a peak in December–January, and from April to October for the Southern Hemisphere, with a peak in August. In 2001, active fires were monitored monthly, revealing significant seasonal changes. The equatorial and southern regions of Africa showed a higher concentration of fires, with fewer in the north. This variation remained consistent for 21 years, up to 2021. A strong correlation exists between latitude and fire abundance. Equatorial countries experience more fires between December and March, while southern countries experience more during the other part of the year. Key factors include biomass accumulation that fuels fires after the rainy season and increasing human pressure, including the need for warming.

The relationship between δ18O values in phosphate (δ18OP) and carbonate (δ18OC) fractions of dental enamel bioapatite is a tool for evaluating the preservation of isotopic signals in fossil teeth. Until now, this relationship has been recognised mainly in ungulates. To expand the database to a statistically representative set of carnivorans, δ18OP and δ18OC values were analysed in 32 samples from modern dogs and foxes collected in Poland. The results obtained for canids are consistent with data reported for other mammals, suggesting a universal model of oxygen isotope fractionation between enamel phosphate and carbonate in mammals, including carnivorans, artiodactyls, and perissodactyls.

Coastline change is a major issue in coastal development because it affects planning and land use. This study investigates how sediment movement influences shoreline dynamics in northern Semarang. Sediments were analysed at multiple locations using core samples, and shoreline change was assessed using Landsat 5, 7 and 8 imagery (1996–2024) processed in Google Earth Engine together with the Digital Shoreline Analysis System (DSAS). The results indicate a barrier-island system with strong sediment transport. A local change since 2021 is linked to the closure of an inlet channel. Shoreline-change analysis in four-year intervals from 1996 to 2024 shows erosion as the dominant long-term process, causing shoreline retreat, although local accretion was observed at points TRG-01 to TRG-04 associated with channel closure and sediment build-up. Differences between satellite-derived shoreline metrics and granulometric data reflect temporal and spatial variability: erosion is a long-term trend, while accretion represents short-term local change. Overall, the Tugurejo coast is highly dynamic, dominated by erosion but with localised growth in specific sectors.

Groundwater salinization and nitrate contamination pose serious threats to water resources in many agricultural regions worldwide. This study investigates groundwater quality and evaluates its suitability for drinking and irrigation in the Sidi Smail Plain (northwestern Tunisia) using geochemical, statistical, modelling and GIS-based approaches. A total of 59 groundwater samples and four surface water samples were collected during the autumn transition (October 2021) and dry summer season (August 2022) and analysed for pH, electrical conductivity, total dissolved solids and major ions. Most groundwater samples were brackish to saline, with average TDS values of 2.225 mg/L in autumn and 2.381 mg/L in summer. Increased salinity during summer was attributed to enhanced evaporation and reduced rainfall. Spatial variability was pronounced, with higher mineralization in the southern plain linked to dissolution of Triassic evaporites and lower values in the north due to dilution from rainfall infiltration and karstic formations. Water Quality Index (WQI) values ranged from 45 to 281, classifying groundwater from excellent to very poor quality. The integrated use of geochemical tools, statistical analysis, WQI and GIS mapping provides a robust framework for assessing seasonal and spatial groundwater quality variations in sub-humid to semi-arid agricultural regions and highlights the need for controlled fertilizer use to protect groundwater from nitrate pollution.