Drought is an extremely negative phenomenon that is becoming increasingly frequent in the southern part of Romania (Oltenia Plain). An insufficiency or lack of precipitation, especially in the warm season, induces a state of stress on the vegetation, damaging it prematurely and decreasing the agricultural yield. Integrating satellite observations into research inventories has practical applications for drought dynamics in plain regions and may significantly contribute to its agricultural sustainability. The aim of our study was to highlight the relationship between drought and vegetation health in the central parts of the Oltenia Plain, namely, the Băilești Plain and Nedeia Plain. We used four different indices (SPI/SPI-CDF-ISND, SPEI, NDVI, NDMI) in order to assess the occurrence of meteorological and agricultural drought and gained a wider picture regarding past and future trends. The results of this study contribute to a better understanding of vegetation health index trends and their implications for climate change. The selected indices were the most suitable for assessing drought according to the literature, and combining all of them helped us to obtain a full picture of drought’s impact on vegetation.

Geographical studies and environment protection research

The steep right slope of the Jiu River (a tributary of the Danube River in the Romanian Plain) in its lower course is one of the hotspots for landslides in Southwestern Romania, constantly facing instability issues due to landslide reactivations and slope-related active deformations. In our study, we aimed to analyze the behavior of the Breasta landslide. The 16-year monitoring data set (2006-2022) contributes to a better understanding of the movement mechanisms associated with triggering factors. Following GNSS monitoring of the profile line since 2006, it became obvious that the most significant morphological changes occurred in the median and final sectors of the landslide, where the slope retreated by 6 to 19 meters. In terms of results, a digital terrain model of the central sector of the Breasta landslide was generated using 5000 GPS-measured points. Using the Kriging method, this sector was enclosed within a rectangle covering an area of 313.40 square meters, with an average height of 108 meters. This sector emphasizes the morphology of the landslide from 2022 in one of the ‘amphitheaters’ that developed after the 2006 reactivation. This paper provides insights into the dynamics of the landslide, helping to discover possible triggering factors of mass movement and periodic changes in the landslide morphology.

Freshwater ecosystems have long been affected by numerous types of human interventions that have a negative impact. Ecosystem disturbance constitutes the worst aquatic response to anthropogenic pressures. The research was initiated by identifying the human pressures on the lakes’ ecosystem, the main objective being to establish, quantify and diminish the aquatic ecosystem responses. The case study was applied in the suburban area of Craiova city for a natural protected area. The chosen methodology is based on the analysis of the response of the 10 ten lakes located along Preajba Valley to human pressures from two perspectives: morphometric parameters of the lakes and indicators of the aquatic condition. For this purpose, a statistical analysis using Google Earth and GIS tools was conducted. The research was completed by field observations during 2009-2019. The results of the study draw attention to the lacustrine surface, its size decreasing from 28 ha in 2009 to 27 ha in 2019. The aquatic vegetation response was completed by determining the tendency of the vegetation extension (which has been ascending for Lakes II, III, VI and X). Following the interpretation of quantitative biocenotic indices, it can be concluded that the species Carassius gibelio is constant (Frequency-86.8% and Abundence-51.8%), being closely followed by Perca fluviatilis and Lepomis gibbosus as accessory species. Our results support the evidence that the high pH (8.2 pH unit), fixed residue (384 mg/dm3), NO2 (0.124 mg/dm3), NO3 (16.28 mg/dm3) and CCOCr (49.7 mg/dm3) confirms the high degree of eutrophication in 2019. The paper suggested the assessment of lakes responses to human pressures as a support tool for sustainable lake ecosystems management in suburban areas.

The paper examines the exceptional floods that appeared within the Raznic river basin, more specifically, their amplitude, causes, and consequences. In order to accomplish the objectives, hydrological data were used to identify the characteristics of flash floods recorded in the years 1972, 2006 and 2023. Finally, the inventory of the socio-economic damages recorded led to the analysis of structural and non-structural measures proposed and implemented by local authorities. The research offers an insight on the dimension of the maximum discharges recorded during exceptional floods (1972 – 190 cm/s; 2006 – 188 cm/s; 2023 – 210 cm/s), their frequency and return period. The importance of the study lies in the fact that it manages to revive both the insufficient scientific and stakeholder concerns on this kind of hydrological risk, issued in a small catchment, considering their recorded effects and the high frequency of occurrence.