Geographies, Volume 5, Issue 2 (June 2025) – 6 articles

We modeled the water level variations in a protected playa-lake system (La Ratosa Natural Reserve, S Spain) comprising two adjacent playa-lakes: La Ratosa and Herriza de los Ladrones. For this purpose, daily water balances were applied to reconstruct the water level. Model results were validated using actual water level monitoring over the past 20 years. We surveyed post-Pliocene geological structures in the endorheic watershed to investigate lake nucleation and to improve the hydrogeological model. Additionally, we investigated the groundwater level evolution in nearby aquifers, which have been profusely affected by groundwater exploitation for domestic and agricultural use. Then, the RCP 4.5 and RCP 8.5 climate change scenarios were applied to forecast the future of this lake system. We found that the playa-lake hydroperiod will shorten, causing the system to shift from seasonal to ephemeral, which appears to be a general trend in this area. However, the impact on the La Ratosa-Herriza de los Ladrones system would be likely more severe due to local stressors, such as groundwater withdrawal for urban demand and agriculture, driving the system to complete desiccation for extended periods. These results highlight the sensitivity of these protected ecosystems to changes in the watershed’s water balance and underscore the urgent need to preserve watersheds from any form of water use, other than ecological purposes. This approach aims to support informed decision-making to mitigate adverse impacts on these fragile ecosystems, ensuring their ecological integrity in the context of climate change and increasing water demand for various uses. Full article

Residential vulnerability in urban spaces is a complex phenomenon subject to a variety of social and economic factors. An example of this scenario is the San Francisco neighbourhood in Villena (Alicante, Spain). This is an area of residential vulnerability because of low levels of education among the population, low income, precarious housing and public insecurity. The main goal in this study was to analyse the profile of the neighbourhood using a mixed methodology based on statistical consultations with several official bodies and a qualitative method derived from surveys conducted with experts and interviews with focus groups made up of specialists, politicians and residents. The most significant results included the demographic stagnation of the local population and, conversely, a rejuvenation of the population thanks to foreign immigration, shaping a multicultural space not free of conflict, exclusion and residential precariousness. New challenges for integration towards a more participatory and safer coexistence emerged, with strategies aimed at curbing abandonment, preventing unlawful occupation of properties and contributing to residential and social regeneration. Full article

The municipality of Grotte di Castro (Lazio Region, Italy) has, for some time, been the subject of various studies concerning the census of artificial cavities. Recent combined applications of LiDAR and photogrammetric surveys have made it possible to develop specific methods for locating entrances and producing 3D models and georeferenced plans. The combined use of these models with geomechanical surveys supported by surface seismic surveys makes it possible to understand the state of health of these buried structures and whether, in the event of an earthquake or as a result of natural decay, they could pose a danger to the population. In this work, which builds on recent studies, a method for assessing the state of these cavities is proposed and tested, essentially to evaluate the risks of collapse and sinkholes. The final objective is to census and discover as many cavities as possible, not only for the mitigation of risk but also for the valorisation of these cavities, which represent a true historical and archaeological heritage—testimonies to the history and evolution of ancient Castrum Criptarum. Full article

Understanding lagoon behavior is crucial for both scientific research and engineering decisions, especially in delicate Arctic environments. Lagoons are vital to coastal areas, often bolstering infrastructure resilience. Since spring 2019, we have monitored the Longyearbyen lagoon (Spitsbergen), vital for coastal erosion defense and serving as a natural laboratory. The location’s well-developed infrastructure and accessible logistics make it an ideal testing site available at any time. It can be used for many natural scientific studies. The lagoon continually changes due to the primary action of waves and tides. This article focuses on gravel spit movement, accelerating in recent years to several meters monthly. Using methods of aerial and satellite images, laser scanning, and hydrodynamic measurements, we have delineated processes, rates, and mechanisms behind this movement. The measurements revealed an accelerating eastward movement of the lagoon spit, from 8 m in the first year to 86 m in the fourth year of observation. This can be explained by a combination of the reconstruction of the Longyearbyen riverbed and increased flow because of climate change. Notably, the expansion does not only occur in the summer months: from September 2022 to February 2023, the spit moved by 40 m, and then, by 19 m from February to June 2023. We found that the bed-load transport along the spit coupled with gravel slides are the primary drives of lagoon expansion and growth. We also investigated movements of groundwater in the spit and changes in gravel contents along the spit, influencing the water saturation of the gravel. Modelling these processes aids in forecasting lagoon system development, crucial for informed management and engineering decisions in Arctic coastal regions. Full article

Detailed hydraulic modeling of a water distribution network (WDN) in an urban area is implemented therein, based on data from geoinformatic tools (GIS), to investigate and analyze the network’s hydraulic response to different scenarios of operation. A detailed mapping of the water meters of the consumers in the urban district is therefore conducted in the frame of a District Metered Area (DMA) zoning. Different consumptions according to water meters and patterns of daily water demand, resulting from both theoretical and measured data from a limited number of smart meters, are used in the hydraulic simulations. The analysis conducted assists common engineering practice to identify critical locations for constructing new hydraulic infrastructure, resulting in the restructuring and reorganization of the DMA, assisting to face existing and common problems of WDNs within the general framework of DMA design and efficient water management. A case study on the WDN of Efkarpia, located in the city of Thessaloniki, Greece, satisfying the principal design criteria of DMAs, is presented in this work, under both normal and emergency conditions. Hydraulic analysis is performed based on different scenarios, mainly consisting of different consumptions according to water meters and different demand patterns, all resulting in high pressures in the southern part of the DMA. Hydraulic simulations are then performed considering two basic operating scenarios, namely the operation of the old DMA of Efkarpia and a new DMA, which is reduced in size. The two scenarios are compared in terms of estimated pressures in the studied area, as well as in terms of energy consumption in the upstream pumping station. The comparisons reveal that the new DMA outperforms the old one, with a large increase in the pressure at nodes where low pressures were assessed in the old DMA, a reduction in daily pressure variation up to 45%, and quite significant energy savings assessed around 21.6%. Full article

Floods represent a significant threat to the livelihoods of individuals and pose challenges to global development prospects. An individual’s age is an essential predictor for adopting flood preparedness measures. In this context, the present study aims to identify community resilience based on age. Two age groups were considered for analysis, i.e., young group (age less than 24 years) and adult group (age over 24 years), using the Flood Resilience Index (FRI) approach through five dimensions of resilience, i.e., the natural, physical, economic, social, and institutional. The data analysis included 200 respondents, with each compromise equaling 100 from both age groups. A total of 34 structured questions were analyzed based on FRI dimensions. The survey results show that the overall resilience in both groups is low, but the adults are relatively more flood-resilient than the young group. Moreover, results of all dimensions show differences between the two groups, with the adult group appearing more resilient than the young group. The study shows that the local authorities and flood protection bodies should focus more on the community’s youth regarding risks and preparedness for flooding. Full article