This paper aims to assess land use and land use change (LULC). For this purpose, supervised mapping on satellite imagery, using the European Space Agency (ESA) SNAP programme from LANDSAT databases, publicly accessible through the European Copernicus portal, was used. At the same time, an analysis of the degree of landscape fragmentation in the study area was carried out, which revealed that, because of the particular fragmentation of small polygons, the best results were obtained via analysis/supervised mapping on satellite images. This method, once validated in the field, reflects the most accurate land use pattern in the analysed area, with wide applications in studies of agriculture, biodiversity, geography, etc. Between 2000 and 2010, significant changes were registered. Artificial surfaces decreased by approximately 400 ha, showing a negative trend in the last period of the interval. Coniferous forests reached their maximum threshold in 2000 (with 114,400 ha) in conjunction with the “Grassland” class, which exceeded 16,700 ha. In 2010, a drastic decrease in “Grassland” was recorded, reaching half of the values of 1990 and 2000, now having only 15,684 ha. Land cover changes were significant when comparing the period before 1989 with 2021. This fact was due to socio-economic changes in society, in large part caused by changes in professions and the way of life of the population.

Snow avalanches are recurrent natural hazards in the Romanian Carpathians, yet their long-term activity remains poorly documented in many massifs due to the absence of historical inventories. This study presents the first dendrogeomorphological reconstruction of snow avalanche activity in the White Valley (Valea Albă), Bucegi Mountains, using European beech (Fagus sylvatica L.) as the indicator species - an approach that is extremely rare worldwide. A multi-method framework integrating dendrochronological analysis, GIS-based quasi-physical avalanche simulation, and systematic field investigations was applied to a stand of 30 beech trees sampled at approximately 1,400 m a.s.l. Tree-ring growth disturbances were quantified using the Growth Change (GC) index following Nowacki and Abrams (1997). Within the statistically reliable period (1975–2024; EPS = 0.876, n = 30), 27 event years were identified, grouping into three avalanche episodes (1975–1983, 1993–1999, 2005–2018) with an episode-based return interval of 15.0 years. Extending the analysis across the full chronological record (1827–2018) yielded 13 disturbance clusters with a mean inter-episode quiescent gap of approximately 7 years. Spatial avalanche modelling using a Voellmy-type friction law on a 2 m resolution DEM indicated that release zones occupy 20.5% of the catchment area, with simulated runout affecting 54.6% of the domain and peak cumulative mass intensities reaching 2,845,000 kg m⁻². Statistical cross-validation confirmed significant positive correlations between the GC-based Affection Index and the log-transformed Distance × Intensity interaction term (r = +0.511, p = 0.008, R² = 0.261), and between individual GC response frequency and tree age (r = +0.657, p < 0.001). These results collectively demonstrate that Fagus sylvatica constitutes a viable dendrogeomorphological proxy for avalanche reconstruction in the Eastern Carpathians, capable of extending the activity record into the early nineteenth century — a period structurally inaccessible to conifer-based approaches -and providing a quantitative baseline for hazard assessment at sites lacking formal documentation.

Water and water habitats are essential to life and to the wellness of the communities that rely on them, as the Danube river is subject to human impact and vice versa, periodic surveys are required to determine the status of its pollution levels. In this work we used known microbiological indicators as well as physico-chemical ones to assess the ecotoxicological status of the Danube river from eleven locations partially forming the “Romanian–Bulgarian Danube Sector”. Most of the microbial communities found, and their densities, could be explained by point and diffuse sources scattered along the sector such as discharged household and farm wastewater, as well as nearby agricultural areas where fertilizers have been used and then leaked in the water stream during rainfalls. However, microbial data on non-point sources that lead to diffuse pollution of surface waters could be linked to such parameters and furthermore shown a slight correlation with the current status of fish communities.

Snow-avalanche activity in the White Valley (Valea Albă), Bucegi Mountains, is reconstructed from European beech (Fagus sylvatica L.), not previously used for this purpose in the Carpathians. Lacking traumatic resin ducts and occluding its wounds rapidly, beech is read through abrupt growth suppression, intra-annual wood anatomy and permanent stem curvature. Field mapping recorded 6.5 km of release scarps and 11.4 ha of deposition across fourteen avalanche paths. Terrain-based routing on a 2 m LiDAR model, with a release criterion consistent with the mapped scarps, delimits the ground reached by released snow and contains the whole sampled stand. Thirty series spanning 1768–2024 were analyzed with the Growth Change index, each year being tested against circular shifts of every tree's suppression (10 000 randomizations) rather than a fixed proportion of affected series. Eight years carry a coincident response (1878, 1952, 1965, 1977, 1978, 2006, 2013 and 2016); four survive false discovery rate control across the 194 years tested. The earlywood–latewood contrast is weakened in rings opening a suppression and singles out 2013, and the reconstructed diameters of twelve deformed stems bound the dates of their curvature, nine of twelve windows containing a dated year. No regional growth depression coincides with 1878, 1977, 1978 or 2006, whereas in 1952, 1965 and 2013 a climatic contribution cannot be excluded. Over 1975–2020, counting 1977–1978 as one winter, events recur every 11.5 years, or every 23 years for the years retained after false discovery rate control, a lower bound on the true frequency.

Land-use and land-cover change (LULCC) is a crucial indicator of environmental transformation and has significant implications for biodiversity, ecosystem services, and climate change. This study investigates land-cover changes between 2017 and 2023 in three distinct mountain regions: the Bucegi Mountains, the Allgäu High Alps, and Mount Olympus. Using remote-sensing data from Sentinel 2 and Geographic Information System (GIS) tools, we analyzed temporal shifts in land-cover types across these regions. The analysis highlights the varying rates and patterns of land-cover transformation in response to environmental and anthropogenic factors. Additionally, the MOLUSCE model was employed to predict future land-cover changes for the year 2029. The findings emphasize the dynamic nature of land-cover in these mountainous areas and offer insights into the potential environmental implications of predicted changes. The Bucegi and the Olympus regions experienced minor land-use changes, while the Allgäu High Alps have the most dynamic changes. The study contributes to a deeper understanding of land-cover dynamics and the applicability of remote sensing and GIS-based predictive models in ecological monitoring.