Catálogo de publicaciones - revistas

<jats:title>Abstract</jats:title><jats:p>Environmental isotopes were used to determine the source and to understand the physical–chemical processes involved in groundwater movement along a flowpath. This study applies groundwater stable isotopes to assess snow-cover influence on the recharge processes of some regional carbonate aquifers of central Italy. Starting with extensively investigated aquifers, 17 springs were selected and sampled (June–October 2016) for isotope analyses. The δ<jats:sup>18</jats:sup>O–δD results follow the local meteoric water line; the low mismatch between the 2016 sampling surveys suggests that those springs are not influenced by seasonal variability. Nevertheless, the average elevations of recharge areas calculated using the vertical isotope gradient were higher compared to those obtained with hypsographic profiles. This means that the relevant contribution to recharge comes from higher elevation areas; hence, snowpack coverage and snowpack persistence over time on recharge areas were analysed using satellite images. Four different relationships between the snowpack characteristics and the elevation of recharge areas have been identified. These offer relevant information about the different degrees of dependence of the regional aquifers of central Italy on the recharge due to high-elevation subbasins where the snowpack cover is significant. A possible correlation emerges between computed isotope recharge elevation and mean snow cover elevation, revealing how snowmelt is a primary source for aquifer recharge. Consequently, to evaluate the risk of groundwater resource depletion in a climate-change scenario, there is discussion on how a potential snow-cover reduction would affect the recharge rate of mountainous aquifers.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Artesian aquifers offer interesting opportunities for water supply by providing a low-vulnerability groundwater resource that is easily abstracted without any installation of pumps or power supply costs. However, hydraulic tests are challenging to perform, notably where the piezometric head is above ground level with free-flowing wells not equipped with valves and open for years. This paper describes a low-cost, easy to reproduce and adaptable device, the free-flowing artesian well device (FFAWD), which is mainly designed with a set of PVC tubes equipped with a pressure probe and a valve. This device is used to perform hydraulic tests on free-flowing artesian wells, to measure the piezometric head of the aquifer and to compute its transmissivity. The practical use of the FFAWD is described and a method is proposed to compute the piezometric head and the transmissivity of the aquifer from this data set (free-flowing well discharge and pressure increase measurements) with any adapted analytical solution, using the Houpeurt-Pouchan method. Artefacts such as post-production effects, surge effects, and the impact of a leaky well are identified to avoid any misinterpretation. The FFAWD was applied to the volcano-sedimentary artesian plain of Pasuruan (Indonesia). The advantages and limitations of using the device, along with the interpretation methodology, are also discussed.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Drought and water scarcity can significantly impair the sustainable development of groundwater resources, a scenario commonly found in aquifers in the Mediterranean region. Water management measures to address these drivers of groundwater depletion are highly relevant, especially considering the increasing severity of droughts under climate change. This study evaluates the potential of managed aquifer recharge (MAR) to offset the adverse effects of drought and water scarcity on groundwater storage. Los Arenales aquifer (central Spain), which was unsustainably exploited for irrigation in the second half of the twentieth century, is employed as a case study. Two neighbouring zones within this aquifer are contrasted, namely, Los Arenales (LA) and Medina del Campo (MC). The primary difference between them in terms of water resources management is the wide-scale implementation of MAR systems in LA since the early 2000s. Several groundwater statistical methods are used. Groundwater-level trend analysis and average piezometric levels show in LA a faster recovery of aquifer storage and less susceptibility to drought compared to MC. On the other hand, standardised precipitation indexes and standardised groundwater level indexes of detrended groundwater-level time series, which do not include the effects of MAR, show that LA can be more negatively affected by drought and groundwater abstraction. The sharper recovery of piezometric levels in LA when considering MAR, and bigger drought impacts observed when the effects of this measure are removed, demonstrate that MAR can effectively alleviate the impacts of water scarcity and drought, providing an adaptation solution to climate change worldwide.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Water suppliers face major challenges such as climate change and population growth. To prepare for the future, detailed knowledge of water resources is needed. In southern Germany, the state water supplier Zweckverband Landeswasserversorgung provides 3 million people with drinking water obtained from a complex karst and alluvial aquifer system and the river Danube. In this study, a combination of different tracing techniques was used with the goal of a multi-scale characterization of the aquifer system and to gain additional knowledge about groundwater flow toward the extraction wells in the Danube Valley. For the small-scale characterization, selected groundwater monitoring wells were examined using single-borehole dilution tests. With these tests, a wide range of flow behavior could be documented, including fast outflow within just a few hours in wells with good connection to the aquifer, but also durations of many weeks in low-permeability formations. Vertical flow, caused by multiple flow horizons or uprising groundwater, was detected in 40% of the tested wells. A regional multi-tracer test with three injections was used to investigate the aquifer on a large scale. For the highly karstified connection between a swallow hole and a spring group, high flow velocities of around 80 m/h could be documented. Exceptionally delayed arrivals, 250 and 307 days after the injection, respectively showing maximum velocities of 0.44 and 0.39 m/h, were observed in an area where low-permeability sediments overlay the karst conduits. With the chosen methods, a distinct heterogeneity caused by the geological setting could be documented on both scales.</jats:p>