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Understanding how environmental and anthropogenic factors influence group living is particularly valuable from an ecological and management point of view, since social systems influence individual feeding, breeding and health, which in turn affect the population size. Foraging strategies, presence of calves and avoidance of predators are known factors influencing group size in bottlenose dolphins, but little research has been done to investigate the concomitant effect of environmental, social and anthropogenic factors. Thus, here we tested the relationship between the group size of a common bottlenose dolphin population in Sardinia (Mediterranean Sea) and some proxies of prey availability (sea surface temperature, seabed depth and habitat type), social context (presence of calves and sex ratio) and sea ambient noise levels, as noise may impair communication and elicit predator avoidance-like response. Group size, both at intra-population (PGS) and individual levels (IGS), was mainly influenced by water temperature, noise, and the social factors. PGS changed with seasons and both PGS and IGS decreased with increasing sea surface temperature, likely suggesting a relationship between group size and the availability of demersal species assemblages, since the latter are known to be strongly affected by temperature. Further, the increase in noise levels led to a reduction in PGS (in presence of calves) and in IGS (in females with calves only). In degraded acoustic environments, the communication between group members may be further impaired by the density of individuals, thus mother-calf pairs may try to reduce the effect of boat noise by staying in a smaller group, where the masking of one’s signals by those from conspecifics decrease.Significance statementThe study highlighted the relationship between SST (sea surface temperature) and clustering pattern of a Mediterranean common bottlenose dolphin population, which in turn may derive from the influence of water temperature on prey abundance and distribution. Further, the effect of noise and boat presence on the grouping of the most vulnerable portion of the population (mothers with calves) was described for the first time. These results support the need for further investigations with the aim of better understanding the effects of warming and noise on coastal dolphins and provide information potentially useful in a management context.

An intense positron sources is a demanding element in the design of future lepton colliders. A crystal-based hybrid positron source could be an alternative to a more conventional scheme based on the electron conversion into positron in a thick amorphous target. The conceptual idea of the hybrid source is to have two separate objects, a photon radiator and a photon-to-positron converter target. In such a scheme an electron beam crosses a thin axially oriented crystal with the emission of a channeling radiation, characterized by a considerably larger amount of photons if compared to Bremsstrahlung. The net result is an increase in the number of produced positrons at the converter target. In this paper we present the results of a beam test conducted at the DESY TB 21 with 5.6 GeV electron beam and a crystalline tungsten radiator. Experimental data clearly highlight an increased production of photons and they are critically compared with the outcomes of novel method to simulate the number of radiated photons, showing a very good agreement. Strong of this, the developed simulation tool has been exploited to design a simple scheme for a positron source based on oriented crystal, demonstrating the advantages in terms of reduction of both deposited energy and the peak energy deposition density if compared to conventional sources. The presented work opens the way for a realistic and detailed design of a hybrid crystal-based positron source for future lepton colliders.

The Poiano karst spring is located in the North Apennines (Italy) and it drains Triassic evaporite rocks with a mean discharge of hundreds of liters/second. Two hydrogeological conceptual models have been proposed (and published) for the spring based on tracer tests. Both models highlighted the contribution of the local streams to recharge of the karst aquifer system, through sinking-stream processes, as well as recharge through rainfall; however, those studies differed in the water courses selected to monitor the recharge processes. The aim of the present research is to increase knowledge about the groundwater recharge processes of the Poiano karst spring with new surveys and analyses, resulting in a large dataset of temporal water stable isotope analyses (δ18O, δ2H), temporal stream discharge measurements, and temporal water tritium isotope data (T). A new hydrogeological conceptual model for the Poiano karst spring is proposed, within which a new list of streams becomes involved in the recharge-processes model based on different sources of water. In addition, the research identifies and confirms the occurrence of groundwater flow processes inside the karst system, such as the piston effect.

Marine protected areas (MPAs) make an essential contribution to the spatial management of critical areas, the conservation of coastal species exploited by human activities, and the sustainable use of marine resources. Within MPAs, fishing closure areas are among the most used small‐scale fishery management tools, even though their effectiveness largely remains untested or controversial. To reduce the impact of small‐scale fisheries on marine resources, a seasonal fishing closure area (SFCA) was established beginning in 2022 in autumn–winter season inside the Capo Caccia–Isola Piana MPA (Sardinia, northwestern Mediterranean Sea). Here, we assessed a posteriori whether the areas of higher habitat suitability for eight species/taxa of relevant ecological value and economic interest to small‐scale fisheries were included in the established SFCA, adequately meeting the ecological objectives of the MPA. Thus, landing data (from 2019 to 2023) were used as occurrence records to develop MaxEnt distribution models for the eight target species/taxa. The model outputs allow us to draw important insights about the spatial adequacy of the SFCA established within the MPA aimed to protect the most exploited marine resources. Furthermore, the modeling exercises were useful for understanding the local processes influencing species' habitat selection and to identify essential areas for the target species that could remain unrevealed in larger‐scale investigations. A modeling approach was used to investigate the spatial adequacy of a seasonal fishing closure area established within a Mediterranean MPA. The local ecological processes influencing fish habitat selection were identified. Insights for small‐scale fishery management were found.

The combined use of hydrogeological and hydrogeochemical methods can provide relevant information about the characteristics of aquifers in studies focused on groundwater protection and management. In the present study, spring discharge monitoring coupled with stable and unstable water isotopes was used to compare the behaviour of adjacent fractured and porous aquifers hosted in a 4.5 km 2 area along the same slope in the northern Apennines, Italy. Based on stable isotope analyses of four springs, a plausible local meteoric water line and a local vertical isotopic gradient were identified. Additionally, tritium contents revealed a recent meteoric origin for groundwater via infiltration in the area. The results of monthly stable isotope monitoring, hourly spring discharge monitoring, hourly rainfall monitoring, and statistical analyses (time series analysis) suggested that although the adjacent aquifers exhibited pronounced geological and hydrogeological differences, few discrepancies were observed regarding groundwater infiltration and release processes. Notably, they exhibited similar temporal delays associated with the response to precipitation events due to the roles of macro-fractures and macro-porosity. Groundwater circulation was characterized by piston and memory effects in both the fractured and porous aquifers, and these effects reflect the roles of micro-fractures/fissures and micro-porosity. The study highlights the relevant contributions of isotopes in studies that focus on spring vulnerability and aquifer processes. Moreover, results obtained in the Pietra di Bismantova site are useful to increase hydrological knowledge on the quite relevant aquifers hosted in Epi-ligurian rock slabs and the surrounding slope deposits in the northern Apennines of Italy.

A comprehensive understanding of bedrock lithology and groundwater circulation is necessary to identify areas prone to landslide initiation and reactivation. This necessity is particularly required in the case of outcroppings of weak rocks such as gypsum that, due to their high solubility and low mechanical strength, can promote slope deformation with the development of caves and collapses. In the Upper Secchia River Valley, where gypsum outcrops extensively and is covered by landslide deposits, an accurate identification of the gypsum outcrops and their distribution is needed to reduce the damage to urbanized slopes. In this paper, a hydrologic and geochemical approach is used in the Montecagno landslide to identify the origin, flow paths and transit time of groundwater circulating inside the landslide body and to identify gypsum deposits and their distribution in the bedrock. The results of groundwater-level monitoring, δ18O-δ2H and 3H isotope analyses and FLOWPC modelling suggest a local and recent origin of the groundwater hosted in shallow flow paths inside the landslide. Chemical and isotope (87Sr/86Sr, δ11B) analyses offer evidence of the presence inside the landslide of small blocks of gypsum that, due to their dimensions, probably have a minor influence on landslide stability. This research demonstrates that the methodology used can provide satisfactory information about bedrock structures and their hydrological aspects.

Changes in soil water content, groundwater flow and a rise in pore water pressure are well-known causal or triggering factors for hillslope instability. Rainfall and snowmelt are generally assumed as the main sources of groundwater recharge. This assumption neglects the role of deep water inflow in highly tectonized areas, a factor that can influence long-term pore-pressure regimes and play a role on local slope instability. This paper aims to assess the origin of groundwater in the Ca' Lita landslide (northern Italian Apennines) and to qualify and quantify the aliquot attributable to deep water inflow. The research is essentially based on in situ monitoring and hydrochemical analyses. It involved 5 yr of continuous monitoring of groundwater levels, electrical conductivity and temperature and with groundwater sampling followed by determination of major ions (Na+, K+, Mg2+, Ca2+, Cl−, HCO3−, SO42−), tracers (such as Btot and Sr2+), and isotopes (δ18O, δ2H and 3H). Leaching experiments on soil samples, hydrochemical modelling and water recharge estimation were also carried out. Results show that the groundwater balance in the Ca' Lita landslide must take into account an inflow of deep and highly mineralised Na-SO4 water (more than 9500 μS cm−1) with non-negligible amounts of Cl− (up to 800 mg l−1). The chemical and isotopic fingerprint of this water points to oilfield water hosted at large depths in the Apennine chain and that uprises through a regional fault line crossing the landslide area. It recharges the aquifer hosted in the bedrock underlying the sliding surface (at a rate of about 49 000–85 700 m3 yr−1) and it also partly recharges the landslide body. In both the aquifers, the hydrochemical imprint of deep water mixed with rainfall and snowmelt water was observed. This indicates a probable influence of deep water inflow on the mobility of the Ca' Lita landslide, a finding that could be applicable to other large landslides occurring in highly tectonized areas in the northern Apennines or in other mountain chains. The paper demonstrates that hydrochemistry should, therefore, be considered as a valuable investigation method to define hydrogeological limits and the groundwater sources in hillslope and to assess groundwater flow patterns in deep-seated landslides.

On March 28, 2016, the toe zone of the apparently dormant Pergalla earthslide-earthflow (Northern Apennines, Italy) had a paroxysmal reactivation. In the course of 2 days, displacements up to almost 8 m severely damaged several houses and roads. At the bottom of the slope, the emersion of rotational sliding surfaces determined the uplift of almost 3 m of the Nure river streambed that was consequently partially dammed. The paper describes the landslide event on the basis of field surveys and analysis of post-event aerial photos, as well as data from geophysical surveys and pre- to post-failure displacement monitoring. It also discusses the possible concurrent causes of the event, including antecedent rainfall, the migration of active streambed channels of Nure river toward the landslide toe in the previous year, and the existence of long-term pre-failure slow movements. It is concluded that these factors, together with the presence of sliding surfaces extending beneath the valley floor, should be primarily considered if a preventive assessment of river damming potential due to streambed uplift should be made for other similar landslides in the Apennines.

Water samples from the river network and from some shallow and brackish springs located in a tectonic window of the northern Apennines of Italy were studied in the frame of a comprehensive hydrogeological investigation in order to better understand the origin and the mixing processes between the two water types noticed also in previous studies (Ca–HCO₃ and Na–Cl). A sampling campaign covering the drought period during year 2010 was planned to gather electric conductivity, temperature and redox potential data along the river network and on groundwater occurrences located inside the tectonic structure. Additionally, eight water samples were collected for hydrochemical (major anions and cations: Na⁺, K⁺, Ca²⁺, Mg²⁺, HCO₃ ⁻, Cl⁻, SO₄ ²⁻ and trace ion Bₜₒₜ) and isotopic (δ¹⁸O, δ²H, ³H) analyses and compared with other eighteen samples from shallow and brackish springs collected near the study site during the period 2005–2012. Moreover, river discharge and water balance estimations were carried out. Results confirmed the presence of old Na–Cl water with salinity progressively increasing up to 5.5 g l⁻¹ at the northern termination of the tectonic window. These values are in agreement with the ions contents of the most mineralized spring (Macognano spring: salinity of 7.6 g l⁻¹), which has been considered as having the deepest and longest flow-path. Stable isotopes and trace ions contents are consistent with rainfall and snowmelt water mixed with brines associated with a hydrocarbon reservoir hosted at depth. Considering as end-member the more mineralized Na–Cl water, a cumulate inflow in the range of 12.9 ± 5.9 l s⁻¹ has been estimated. This aliquot is released into the river network with different mixing proportions by the groundwater occurrences discharging from the autochthonous flysch unit.

Scintillating homogeneous detectors represent the state of the art in electromagnetic calorimetry. Moreover, the currently neglected crystalline nature of the most common inorganic scintillators can be exploited to achieve an outstanding performance boost in terms of compactness and energy resolution. In fact, it was recently demonstrated by the AXIAL/ELIOT experiments that a strong reduction in the radiation length inside PWO, and a subsequent enhancement in the scintillation light emitted per unit thickness, are attained when the incident particle trajectory is aligned with a crystal axis within ~ 1°. A SiPM-based system has been developed to directly probe this remarkable effect by measuring the scintillation light emitted by a PWO sample. The same concept could be applied to full-scale detectors that would feature a design significantly more compact than currently achievable and unparalleled resolution in the range of interest for present and future experiments.