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Abstract The spatial gradients created after the installation of large reservoirs produce a great diversity of biotopes, which affects the distribution and structuring of aquatic communities, mainly fish. Thus, we hypothesized that the fishes living in the lotic stretch (river zone, closest to the natural environment) of the reservoir would have lower overlap and higher niche breadth than fishes living in the lentic stretch. Samples were collected in six sections (lentic and lotic) of the Chavantes Reservoir, middle Paranapanema River. A total of 1478 individuals distributed in 13 species were sampled in both stretches. Many resources were acquired by species, and we observed that nine species present significant differences when comparing the two stretches. Furthermore, only \emph{Schizodon nasutus

Introduction: Maternal immune activation (MIA) is closely related to the onset of autism-like behaviors in offspring, but the mechanism remains unclear. Maternal behaviors can influence offspring’s development and behaviors, as indicated in both human and animal studies. We hypothesized that abnormal maternal behaviors in MIA dams might be other factors leading to delayed development and abnormal behaviors in offspring.Methods: To verify our hypothesis, we analyzed poly(I:C)-induced MIA dam’s postpartum maternal behavior and serum levels of several hormones related to maternal behavior. Pup’s developmental milestones and early social communication were recorded and evaluated in infancy. Other behavioral tests, including three-chamber test, self-grooming test, open field test, novel object recognition test, rotarod test and maximum grip test, were performed in adolescence of pups.Results: Our results showed that MIA dams exhibit abnormal static nursing behavior but normal basic care and dynamic nursing behavior. The serum levels of testosterone and arginine vasopressin in MIA dams were significantly reduced compared with control dams. The developmental milestones, including pinna detachment, incisor eruption and eye opening, were significantly delayed in MIA offspring compared with control offspring, while the weight and early social communication showed no significant differences between the two groups. Behavioral tests performed in adolescence showed that only male MIA offspring display elevated self-grooming behaviors and reduced maximum grip.Discussion: In conclusion, MIA dams display abnormal postpartum static nursing behavior concomitantly with reduced serum levels of testosterone and arginine vasopressin, possibly involving in the pathogenesis of delayed development and elevated self-grooming in male offspring. These findings hint that improving dam’s postpartum maternal behavior might be a potential regime to counteract delayed development and elevated self-grooming in male MIA offspring.

A hardfill dam can reduce the natural damage caused by the development of quarries and recycle submerged resources. However, the particle size distribution of the aggregate can result in large variations in the mix design, resulting in a wide range of strengths in the hardfill dam body. Therefore, quality control during construction is crucial, and the stability of the dam body after construction should be thoroughly examined in advance. This study investigated the strength characteristics of hardfill dam materials according to the particle size and mixing ratio through indoor uniaxial compressive strength tests using large specimens and uniaxial compressive strength tests for field compaction and collected cores. Furthermore, the stability of hardfill dams with three types of slopes during earthquakes was evaluated through a finite element analysis. The distributions of stress in the hardfill dam body and the strength required to stabilize the dam body were investigated. Except for a 1:0.6 inclined hardfill dam body to which artificial seismic waves were applied, the overall strength range calculated from the indoor specimens and field compaction cores exceeded the required hardfill strength, thereby ensuring stability in the event of an earthquake. [ABSTRACT FROM AUTHOR]

In this study, radio telemetry was used to examine the upstream spawning migration behaviour of anadromous brown trout (sea trout), Salmo trutta L., in a boreal river system, the River Isojoki, western Finland. The aim was to study the movement activity and migration characteristics of trout during the upstream spawning migration, as well as to locate the important spawning habitats and study the spawning characteristics. Furthermore, the authors analysed how flow conditions and a hydropower dam, with adjacent fishways, affected the upstream spawning migration. Tagged trout spawned in both the main stem and four tributaries, with spawning taking place from early October to November. The movement activity of radio‐tagged trout was influenced by a hydropower dam (Perus dam), with spring migrators spending prolonged periods at the dam area, postponing the migration upstream. Flow conditions affected the total time spent at the dam area, as well as the movement activity in the free‐flowing sections above the dam, with increasing flow stimulating activity. In addition, time of river ascent and location of spawning area had a significant effect on the movement activity of tagged trout. These results are further evidence that synergistic effects of flow and migratory obstacles can negatively influence migrations of anadromous fish, regardless of constructed fishways. The management of flow regimes and the efficiency of fishways are vital, as climate change will likely influence the flow and increase the water temperature of boreal river systems, further aggravating issues caused by obstacles. [ABSTRACT FROM AUTHOR]

The seepage of the dam is an important representation of the operation characteristics of the dam, and there are many factors affecting the seepage with a certain lag. It is still difficult to predict its change and sensitivity because of complex operating conditions. At present, the lag-sensitivity of influence factors of the dam seepage has not been studied. The time series influence factors of seepage are determined by HTRT (hydrostatic-thermal-rainfall-time) model in this paper. To avoid the pseudo fitting of conventional methods, HTRT model nested random forest algorithm is used to establish the predicting model of the dam seepage. And MIC algorithm is used to achieve the dual purposes of time lag and sensitivity analysis. Firstly, the time lag of relationship between seepage and its influencing factors is characterized, and the most appropriate lag time of the HTRT model factors is determined. Secondly, independent correlation analysis on all influencing factors is carried out and the sensitivity of each factor is analyzed by MIC. Meanwhile, the sensitivity of the factors to seepage is quantitatively analyzed by the two parameters of %IncMSE and IncNodePurity of RF algorithm. The sensitivity of influencing factors is analyzed by comparing MIC results with RF results. Combined with the case, taking the error of fitting prediction as the evaluation index of seepage prediction, the prediction accuracy of MIC-RF model, RF model and MIC-BPNN (Back Propagation neural network) model is calculated and compared. Case study showed that MIC- RF monitoring model has high prediction accuracy, strong adaptability and high robustness in dam seepage, and the sensitivity and time lag of influencing factors can be quantitatively analyzed. The water pressure and rainfall of the lag time are 14 days and 16 days respectively. The sensitivity study of the time series influencing factors of seepage showed that the water pressure component is the main controlling factor of seepage, and rainfall component is more sensitive to later stage. The MIC-RF model can be used as a new dam seepage safety monitoring model. [ABSTRACT FROM AUTHOR]

This study is presenting a multidisciplinary approach for mitigations of water resources in the irrigation, water supply, energy, and flood protection using hydrological model coupled with multi-criteria decision analysis (MCDA). The study area is originated in the northern Afghanistan with serious water issues. Soil and Water Assessment Tool (SWAT) was adopted for the hydrological modelling. The model was calibrated and validated using monthly streamflow from 2010 to 2018. The current irrigation state of the watershed was revised based on the crop water requirements and land area to address water shortages. The investigations lead to an engineering-based solution (dam construction) to regulate and control the streamflow, especially during winter and flood season. Analytical hierarchy process (AHP) based on expert's opinions were used to determine suitable dam site locations. Then, the dam was added to the SWAT model for dam's impact assessment. The dam reservoir capacity (197,900,938 m3), dam storage area (748 ha), dam height (69 m), electricity generation (Ave = 25.4 MW, Min =16.23 MW, , Max = 66.5 MW), and flood protection ability were estimated. Finally, cost–benefit analysis (CBA) was conducted to ensure the project feasibility. The CBA proves the feasibility and applicability of proposal. The surplus water can address the water shortages with an extra capacity of irrigating 17,180.5 ha or provision of water supply for the Mazar-i-Sharif city (the fourth biggest city in the Afghanistan). These findings can be used as guidance for the decision-makers in the BRB for the future development of water resource management strategies. [ABSTRACT FROM AUTHOR]

The impact of the damming of the Sava river for the Brežice hydroelectric power plant on the rise of the groundwater level was studied in the intergranular aquifer of the Krško field and the Vrbina area, Slovenia. The study is based on the application of hydrogen and oxygen isotopes (18O, 2H and 3H). Parameters were determined for precipitation, surface water, and groundwater for periods before and after the filling of the accumulation basin, with the aim of evaluating the groundwater–surface water interaction and to elucidate the impact of the hydroelectric dam on aquifer recharge processes. The results show the proportions of the surface water component in groundwater sampled from four wells at high and low water conditions, separately for the period before and after the filling the accumulation basin. After filling the accumulation basin, the proportion of the Sava river component at high water conditions increased from 60% to 80% in the Brege and Drnovo wells (drinking water resources), from 50% to 80% in the Cerklje well and to almost 100% in the near-river NEK well. Combined with previous studies, the results provide important information about the direction of groundwater flow in the aquifer and improve the conceptual model of the study site. [ABSTRACT FROM AUTHOR]

Dams are studied not only for potential advantages but also for possible environmental repercussions. The objective of this case study is to see the effects caused by Gomal Zam Dam on temperature, humidity and precipitation in their surroundings, both spatially and temporally. The meteorology parameters' characteristics have been detected using two different approaches, Mann–Kendall statistical test and Sen's slope estimator. Data stations chosen were those that have been close to the dam and sufficiently far away from the dam. As a consequence, although temporal changes in mean heat were established, periodic and regional disparities in humidity readings were found. [ABSTRACT FROM AUTHOR]

After a major accident in August 2009 at the Sayano‐Shushenskaya Hydroelectric Power Plant (SS HPP), all 10 hydroelectric units (HU) with a total capacity of 6400 MW failed. After investigating the causes of the accident and the reconstruction of the hydroelectric power plant, there was to develop a methodology for monitoring the operation of the newly commissioned HU. For inspection, a method was developed based on monitoring the natural frequencies of the dam structures and forced vibrations caused by the operation of the equipment. The article presents the main results of this study. Within the framework of the proposed approach, monitoring was carried out at various observation points of the dam structures and the turbine hall, as well as on a network of remote seismic stations. Based on the data recorded since 2009, an assessment of the parameters of dynamic impacts arising from the operation of hydraulic units of various types in different load modes on the elements of the HPP structure was carried out, and cause‐and‐effect relationships between changes in the operating modes of equipment and recorded vibrations in dam structures were investigated. An estimate of the general level of vibrations during the operation of various types of hydraulic units is given. As a result, the operating modes of hydraulic units are determined, in which there is a multiple increase in the amplitude of natural vibrations of the dam, an assessment of the operational characteristics of hydraulic units is given, taking into account the impact of seasonal conditions and changes in the water level in the reservoir. [ABSTRACT FROM AUTHOR]

The objective of this research is to create an automated irrigation system using two threshold method for rice forming in the Jorolot irrigation area, Cimahi City, West Java Province, Indonesia, which addresses the problem of fluctuating water supply This issue includes water deficits during the dry season, which threatens rice growth, and excess water during the rainy season, leading to flooding and crop destruction. The method used includes one-dimensional hydraulic modeling of irrigation channels to determine two threshold of channel water level elevation, as well as water availability quantification based on flood, normal, and dry clusters. Furthermore, the system's design involved utilizing the Decision Supporting System (DSS) data communication to monitor and respond to dry or flood events in real time, thereby increasing the system's overall performance. The Jorolot irrigation area, which covers 15.5 hectares, sources its water from the Jorolot Dam, with a primary channel length of 1135 m and a secondary channel length of 536 m. The results showed that the waterlevel in the primary canal for normal conditions is 0.1 m

Numerical analysis of pore water pressure changes and the evolution of vertical deformations are the main aspects of the behaviour monitoring of an earth dam. This study analyzed the main aspects of the behaviour monitoring of the Plopi Dam, built on the Gurguiata River, in the northwest of Ia Şi County, Romania. The main data taken into consideration are the dam body's type and material, the foundation's soils, and the dam's monitoring equipment. For tracking the evolution of the pore water pressure, 12 piezometers are used. The Plopi Dam is equipped with 19 piezometers, of which 9 piezometers (marked with B) show the route of the infiltration curve through the dam body and 10 piezometers (marked with F) have the bottom level in the base of the foundation and record the variation of groundwater levels in the aquifer. The paper presents the pore-pressure ratios in embankment material throughout its existence, mainly in the last 12 years, and the influence of external stresses on the hydrostatic levels. Data obtained for a period of 45 years (1978-2023) from 11 landmarks, placed on the dam canopy, were used in the settlement analysis of the embankment The filling in the dam body is still being consolidated, the settlements are significant, the pore pressures are high, so the monitoring of the dam's behaviour is done continuously so that the dam is safely exploited. [ABSTRACT FROM AUTHOR]

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Dam impoundment can cause many adverse impacts on fish assemblages upstream of dams. Here, we investigated fish diversity in one plateau riverine reservoir (Wanfeng Reservoir) using environmental DNA (eDNA) metabarcoding technology. The following conclusions were drawn: (1) 39 species of fish were monitored belonging to 9 orders and 13 families in the Wanfeng Reservoir, most of which were Cypriniformes and included a variety of common farmed fish belonging to Culter, Oreochromis, Acipenser, and Clarias; (2) the fish assemblage structures in the Up (upstream section), Mid (midstream section), and RA (reservoir area section) of this reservoir was significantly different (p-value < 0.01); (3) among the 7 environmental variables that were measured (Tem, TDS, Sal, pH, DO, NH4+, and Tra), DO (p-value < 0.01) and pH (p-value < 0.05) were the main environmental stressors causing differences in fish assemblages in different sites of the Wanfeng Reservoir. This study concluded that dam construction in the karst region provided habitats for the establishment and dispersal of exotic fish. [ABSTRACT FROM AUTHOR]

The effects of hydropower plants (HPPs) and climate/land use change pose a threat to the natural river regime. Although some approaches distinguish the climate action from anthropogenic influence on hydrological regimes in large basins, few methods propose to separate the climate effects from the regulation consequences of unique/few dams. This paper presents a new method to quantify effects of HPP and climate change/land use under the main altered river regime components, which is based on flow duration curves. The method was applied in the Grande River (Brazil), which is regulated by a large reservoir (with surface area > 70 km2). The indicators of hydrological alterations and the range of variability approach indicated that all drivers' effects promoted a moderate alteration in five regime components. The Itutinga‐Camargos HPP implications were the major driver, with a contribution higher than 90% in every component, and it was responsible for a 0.28 × 109 m3 year−1 reduction in water superficial availability downstream. The flow regimes in headwater watersheds can be highly sensitive to dam operations, but other factors may aggravate their effects on river dynamics. The quantification of anthropogenic actions has possible applicability in other systems worldwide to assess the ecosystem services of flow regimes. [ABSTRACT FROM AUTHOR]

Copyright of Ingeniería del Agua is the property of Universidad Politecnica de Valencia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In 1944, in the context of the electrification of Portugal, the Hidroeléctrica do Cávado company (HICA) started exploring the Cávado River. Over two decades, HICA constructed five hydroelectric systems, including dams and power stations, but also small settlements to house the company's workers, technicians, and managers. Through a systematic analysis of these hydroelectric architectures, this paper identifies the underling rationale and principles involved in HICA’s design decisions. It presents the initial studies that helped determine the location of the dams as well as the constructions built around them. The paper’s argument is focused is on the settlements built for power station workers, which were fundamental to the construction and maintenance of the related infrastructure. The paper investigates the domestic nature of the settlements, the circumstances that surrounded their construction and the architects involved in the process. Over and all, these projects initiated a process of deep transformation of the Portuguese landscape, in which the HICA’s lacked a clear and identifiable vision for the Cávado Valley, whose main concern was to maintain absolute control over the landscape and the physical layout of their power plants and workers’ settlements. [ABSTRACT FROM AUTHOR]

The study was carried out in the area of three dam reservoirs: Blizne and Maziarnia (Voivodeship of Podkarpackie) and Nielisz (Voivodeship of Lublin). The main parameter differentiating the reservoirs was the water retention time and the manner of water discharge from the reservoirs. Three test sites were designated in the area of each reservoir: in the river zone of the reservoir, in the central part of the reservoir, and near the reservoir dam. At these sites, the concentrations of suspended sediment in the water and the content of organic matter in it, the concentrations of total phosphorus and total nitrogen, as well as chlorophyll a were monitored. In addition, two control sites were established: on the river upstream of the reservoir and on the river downstream of the dam, respectively. At these points, the concentrations of suspended sediments in the water and their organic matter content were recorded. The obtained results of the study and multivariate analysis of the data showed that morphometric parameters (including water retention time) of reservoirs and the method of water discharge influence water quality in downstream rivers. It was found that by using lower discharge and ensuring a sufficiently long retention time of water in the reservoir, it is possible to effectively limit the negative aspects of hydrotechnical structures' impact on the natural environment. In practice, the observed relationships may constitute an important and missing link in the aspect of minimising undesirable side effects of this type of hydrotechnical objects. [ABSTRACT FROM AUTHOR]

Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An embankment dam is a large artificial embankment made by placing and compacting various compositions of soil, sand, clay or rock. One of the rock fill dams located in the Buleleng Regency, Bali Province, namely the Tamblang Dam which is planned to be utilized to meet the raw water needs in the Buleleng Regency in particular and the Bali Province of 510 liters/second, irrigates irrigated rice fields in Bungkulan and in Bulian with an area of 588 Ha, as a micro hydro power generator of 2 x 269 MW, as well as other uses for flood control and tourism. At first the Tamblang Dam was a rock fill dam with an upright core made of clay material. After conducting test pits at 30 borrowed areas and soil investigations at an independent laboratory, the volume of the core zone material according to specifications cannot meet the needs of the core material. There are alternative solutions to the problem, namely bringing in core zone material from outside the project site or changing the original clay core design into an asphalt concrete core. This study applies the Value Engineering (VE) method in which an increase in function at a fixed cost or an increase in function will be obtained by reducing costs or reducing costs for a fixed function or increasing costs and increasing functions. [ABSTRACT FROM AUTHOR]

Soil water erosion is a major phenomenon that threatens almost all watersheds in the Mediterranean area, nowadays. The worsening of this phenomenon in Algeria affects soil capacity to ensure its ecological functions and socio-economic purposes which depend on it. Concurrently, the storage capacity of Algeria dams has considerably decreased as a result of excessive silting. The above issue motivated this study, which aims to establish mechanisms for prioritizing to improve the economic efficiency of agricultural land and the long-term viability of dams in the largest metropolitan basin of Algeria ‘Coastal Algiers 2a basin’. This basin, which is urbanized over 50% of its area, contains six large dams with a total capacity of 540 Million m³ and one of the most important agricultural zones in Algeria. Common decision support frameworks have been implemented to predict the areas that are potentially exposed to erosion and sediment deposition threatening the dam capacity using the Soil and Water Assessment Tool (SWAT) and the Revised Universal Soil Loss Equation (RUSLE). To achieve this, rainfall, climatic, hydrometric, land use, soil, digital elevation, and satellite data were used by the two spatially soil loss models. The results show a dependency between the two statistical models with respect to low, medium and high erosion risk areas and its evolution from the eastern to the western region of the watershed. Regarding the deposition of sediments at the dams, the two models only partially explain the rate of sediments observed at the level of the dams’ basins whose relative errors exceed 4%, 8%, 60%, 30% and 40% respectively for the Meurad, Bouroumi, Keddara, Boukerdane and El Hamiz dams. The canonical analysis (CC) revealed that the average slope, vegetation cover and the available water capacity in the soil of the basin are the most important parameters influencing the soil loss provided by the two models. [ABSTRACT FROM AUTHOR]

The current situation of the water resources of Istanbul, which is one of the important metropolises of Europe, should be known and constantly monitored by the reasons of the rapid increase in the city population, the acceleration of production-related industrial activities, the expansion of the city with construction activities, and the decrease in precipitation. The purpose of this study was to reveal the situations of surface sediments collected from Istanbul water reservoirs in terms of PCDD/Fs and DL-PCBs, to identify possible sources, and to conduct their ecological risk assessment. Total PCDD/Fs and DL-PCBs concentrations varied between 28.13 and 457.4 pg/g (average 136.8 pg/g) and 12.19–340.1 pg/g (average 72.09 pg/g). The corresponding TEQ values of PCDD/Fs and DL-PCBs were between 0.53 and 5.37 pg TEQ/g (average 2.23 pg TEQ/g) and 0.02–0.44 pg TEQ/g (average 0.12 pg TEQ/g), respectively. Octachlorodibenzo-p-dioxin (OCDD) is the dominant congener by constituting about 75% of the total PCDD/Fs on average, while congener distributions of DL-PCBs showed the dominance of PCB-118 and PCB-105. The sediments taken from Kazandere dam have the lowest pollution levels for both PCDD/Fs and DL-PCBs. The highest PCDD/F and DL-PCB amounts were measured in sediments of Alibey and Elmalı dams (closest to highly populated settlements of Istanbul), which are most affected by the air pollution caused by the traffic, commercial/industrial combustion (like waste incineration facility) and combustion for residential heating. Almost all the sediments have total dioxin-like toxicity levels higher than the safe threshold level (with two exceptions) of 0.85 pg TEQ/g dw, proposed for ecological risk. Health risk assessment shows that levels of dioxin-like compounds would result in a total intake of 0.33 pg TEQ/kg bw/day even in the worst-case scenario, not exceeding the tolerable daily intake value of 1 pg TEQ/kg bw/day. Among exposure pathways, consumption of fish constitutes almost all the total intake, while contributions of other pathways are minimal. [ABSTRACT FROM AUTHOR]

The June 2013 disaster in Kedarnath hit the Mandakini–Alaknanda river valley, resulting in devastating floods. This study deals with the pre- and post-flood event changes in the channel morphology and aims to investigate the geomorphological processes under river management in the Alaknanda valley, NW Himalaya and how the hydroelectric reservoir may have impeded the natural impact of the disaster and created geomorphic discontinuity. This work analyses the spatio-temporal variations in channel morphology over the last decade 2010–2020, discussing the impact of 2013 extreme event; the role of gradient in morphological patterns in river basin system. It highlights how the channel parameters like the thalweg shifts, active channel width, and area under sedimentation responded, from headwaters to lower gradient Lesser Himalayan zones to the 2013 event and suggests that any positive changes in these parameters diminish soon after the reservoir. The study implies that the capability of the reservoir to adjust the sediment load of the event in its upstream is an immediate short-term effect, but brings out the fact that it creates a geomorphic disconnect in the channel between upstream and downstream channel reaches of the reservoir. This disconnect may have a negative impact on sediment storage and sediment–water routing of the river and should be factored into the dam design ensuring natural continuum of geomorphic processes. Further, the study argues that the terrain north of the Main Central Thrust (Higher Himalaya) should be kept free from major human interventions to reduce flood hazards. [ABSTRACT FROM AUTHOR]

Forrest Merton Holly Jr dealt extensively with numerical modelling of unsteady flows and dispersion processes associated with the operation of hydropower and thermal power plants, and often with alluvial sediment transport by rivers. His expertise, energy, and genial personality led him to become President of the International Association of Hydraulic Engineering and Research (IAHR) during 2000–2003. Holly's last hydraulics project engaged his expertise and was done with the friendly aplomb for which he was well known. This forum paper portrays Holly engaged in his last project, which involved the practical application of numerical modelling of unsteady flow to and through a navigation dam. [ABSTRACT FROM AUTHOR]

Eurasian beavers Castor fiber are important ecosystem engineers, able to modify freshwater environments and influence local biodiversity. Beaver activity affects not only aquatic ecosystems but also terrestrial habitats and organisms. In recent times, beaver populations have been detected in Central Italy. In this work, we determined the use of beaver lodges and dams by native animal species in Central Italy through intensive camera trapping between March 2021 and May 2022. Saproxylic beetles were searched by sight in spring and summer on lodges, dams, and gnawed trunks on river shorelines. We collected 132 records belonging to at least 17 species on beaver dams and lodges, several of them of conservation concern (e.g. the European bittern Botaurus stellaris and the endemic water vole Arvicola italicus). The most detected species within beaver structure was the yellow-necked field mouse Apodemus flavicollis, with 67 independent videos. Despite being confirmed as a nocturnal species, in our study area, A. flavicollis showed an activity peak on bright moonlight nights. The lodge may thus be used as a protection site from predation risk for small rodents, which may benefit from the beaver presence. By building dams and lodges, Eurasian beavers can increase habitat heterogeneity, thus promoting biodiversity increase and improvement. The potential expansion of beaver populations into these ecosystems may serve as a biotic restoration strategy. [ABSTRACT FROM AUTHOR]

Current research was done to evaluate the level of pesticide residues and heavy metals in fish and water bodies. Surface water samples and samples of Oreochromis niloticus and Tor putitora were collected from different sites from Rawal and Simly Dams. Following the physicochemical analysis of water samples, heavy metals were analyzed by Atomic Absorption Spectrophotometer (AAS) while pesticide residues were detected by GC–MS. Acid digestion of fish muscles was done for heavy metal analysis. Soxhlet extraction was used to extract pesticide residues from fish samples, which were concentrated in a rotary evaporator followed by GC–MS analysis. The physicochemical analysis of water samples revealed pH within the WHO guidelines. Pb, Cr, Cd, and Ni found in Rawal and Simly Dam water were higher than the prescribed WHO guidelines. The average heavy metal concentration in all fish samples was also high. Toxic pesticides detected in Rawal Dam water and fish samples included HCB, Heptachlor, 2, 4′-DDT, 4, 4′-DDT, and 4, 4′-DDE, whereas HCB, PP-DDT, OP-DDE, and Chlordane were detected in Simly Dam water and fish samples. The study emanates the menace of possible bioaccumulation of heavy metals and toxic pesticides in food chain. [ABSTRACT FROM AUTHOR]

Microorganisms play a critical role in the process of nitrogen removal in aquatic environment, which is regulated by multiple environmental factors. As a high-altitude region, the Qinghai-Tibet Plateau has unique composition of bacterial communities due to its unique geographical conditions, which may affect the nitrogen conversion of Plateau rivers. However, the regulation of nitrogen removal by environmental factors and bacterial community in high-altitude rivers has been rarely reported. This study investigated denitrification, anammox, and dissimilatory nitrate reduction to ammonium rates as well as the community of bacteria and denitrifiers in the Yarlung Zangbo River. The results showed that denitrification was the dominant nitrate removal process. Redundancy analysis revealed that environmental factors including suspended particulate matter, chemical oxygen demand, dissolved oxygen, nitrogen and phosphorus content, electrical conductivity, and pH explained a large amount of the variance in bacterial community. Denitrifiers carrying nitrite reductase-related gene were an important driver of denitrification in the Yarlung Zangbo River. The low water temperature brought by high altitude significantly reduced the denitrification rate. The cascade dams on the river affected the particle size distribution of sediment, changed the community composition of bacteria and denitrifying bacteria, and increased the denitrification rate in the downstream. Our findings highlight that nitrogen removal processes in high-altitude rivers are jointly regulated by environmental and anthropogenic factors through shaping denitrifier abundance. [ABSTRACT FROM AUTHOR]

Copyright of LHB: Hydroscience Journal is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hydrological connectivity is a basic feature of river ecosystems, responsible for important ecological processes. Human activities, however, have progressively modified natural connectivity, threatening the maintenance of aquatic biodiversity.Neotropical potamodromous fish depend heavily on fluvial connectivity to complete their life cycles. However, important ecological aspects remain poorly understood, especially in river systems with limited floodplain development (i.e. channelized rivers and drylands), where the environment poses constraints to fish recruitment. The Uruguay River Basin is such a system, with several migratory fish, small floodplain areas, and limited information about recruitment dynamics and nursery grounds.The lack of information on critical habitats limits conservation and management actions, especially in scenarios of increasing environmental degradation and river regulation. This study investigated recruitment dynamics of migratory fishes in the Middle Uruguay River, a long fluvial segment targeted for hydropower development. The study investigated spatial variations in the abundance, composition and size structure of juvenile fish among different sites along an extensive fluvial gradient (ca. 650 km), comparing the main channel with tributaries.Juveniles of migratory fish were widely distributed in the region, totalling nine species, with a predominance of Characiformes. Spatial distribution was variable among species and size classes, with a differential use of tributaries, wetlands and the main channel. Juvenile composition differed between sampling sites and environments, and was correlated with different limnological and spatial variables. Greater abundances occurred in the mouth of a tributary where a small floodplain develops during the wet season.The results emphasize the importance of fluvial connectivity for fish migration, dispersal and recruitment, providing valuable information about migratory fishes in river systems with limited wetland development. These findings have significance for the management and conservation of migratory fish under scenarios of hydropower expansion, as comprehensive studies on recruitment are rare in free‐flowing rivers. [ABSTRACT FROM AUTHOR]

This paper provides a review of using Interferometric Synthetic Aperture Radar (InSAR), a microwave remote sensing technique, for deformation monitoring of hydroelectric power projects, a critical infrastructure that requires consistent and reliable monitoring. Almost all major dams around the world were built for the generation of hydropower. InSAR can enhance dam safety by providing timely settlement measurements at high spatial-resolution. This paper provides a holistic view of different InSAR deformation monitoring techniques such as Differential Synthetic Aperture Radar Interferometry (DInSAR), Ground-Based Synthetic Aperture Radar (GBInSAR), Persistent Scatterer Interferometric Synthetic Aperture Radar (PSInSAR), Multi-Temporal Interferometric Synthetic Aperture Radar (MTInSAR), Quasi-Persistent Scatterer Interferometric Synthetic Aperture Radar (QPSInSAR) and Small BAseline Subset (SBAS). PSInSAR, GBInSAR, MTInSAR, and DInSAR techniques were quite commonly used for deformation studies. These studies demonstrate the advantage of InSAR-based techniques over other conventional methods, which are laborious, costly, and sometimes unachievable. InSAR technology is also favoured for its capability to provide monitoring data at all times of day or night, in all-weather conditions, and particularly for wide areas with mm-scale precision. However, the method also has some disadvantages, such as the maximum deformation rate that can be monitored, and the location for monitoring cannot be dictated. Through this review, we aim to popularize InSAR technology to monitor the deformation of dams, which can also be used as an early warning method to prevent any unprecedented catastrophe. This study also discusses some case studies from southern India to demonstrate the capabilities of InSAR to indirectly monitor dam health.

A dam is an important piece of infrastructure for ensuring economic and social development. During operation, because of environmental changes, aging materials, and other factors, a dam may develop accident risks and once it fails, it poses a great threat to society. Therefore, it is of great significance to use reasonable methods for analyzing the monitoring data collected by a dam safety monitoring system and evaluate a dam’s behavior to ensure operation safety. At present, the existing methods are mainly devoted to evaluating the local state of a dam according to the monitoring information of a single measuring point. Relatively few studies are available on the evaluation methods for the overall state of a dam, and the existing methods are mainly qualitative and subjective. To address this problem, the residual between the model calculated value and the measured value was taken as the research basis. The concept of the fusion residual, an important index for characterizing the overall behavior of a dam, was promoted. Combined with the information entropy theory, the variation of residuals at different measuring points was studied, and the fusion weight of residuals at each measuring point was analyzed. The fusion residual was calculated. Based on the distribution analysis of the fusion residual, a concept cloud representing the different states of a dam, namely, the evaluation criteria, was established using a reverse cloud generator and a forward cloud generator. On this basis, an evaluation model of the overall behavior of a dam was established and combined with the cloud similarity algorithm. The example shows that the evaluation method can effectively identify the abnormal value of a dam and evaluate its overall behavior. The evaluation results are reasonable and reliable. The model can evaluate the overall behavior of a dam quantitatively and objectively, and the evaluation results are reasonable and reliable, providing an important reference for the safe operation of a dam.

The article discusses a new mathematical method for comparing the consistency of two particle size distribution curves. The proposed method was based on the concept of the distance between two graining curves. In order to investigate whether the distances between the particle size distribution curves are statistically significant, it was proposed to use the statistical test modulus-chi. As an example, the compliance of three sieve curves taken from the earth dam in Pieczyska on the Brda River in Poland was examined. In this way, it was established from which point of the dam the soil was washed away. However, it should be remembered that the size of the soil grains built into the dam does not have to be identical to the grain size of the washed out soil, because the fine fractions will be washed away first, while the larger ones may remain in the body of the earth structure.

The paper presents the approach for optimization of preventive/technological measures increasing the safety of tailings pond dams. It is based on the combined use of monitoring results as well as advanced 3D finite element (FE) modeling. Under consideration was the eastern dam of Zelazny Most Tailings Storage Facility (TSF). As part of the work, four numerical models of the dam and the subsoil, differing in the spatial arrangement of the soil layers, were created. For this purpose, the kriging technique was used. The numerical models were calibrated against the measurements from the monitoring system. In particular the readings acquired from benchmarks, piezometers and inclinometers were used. The optimization of preventive measures was performed for the model that showed the best general fit to the monitoring data. The spatial distribution and installation time of relief wells were both optimized. It was shown that the optimized system of relief wells provides the required safety margin.

Structural solutions in terms of fish ladders and the use of natural materials to construct them often raise concerns regarding the possibility of using the standard calculation methods. The fish ladder being designed on the Wisłok river consists of three pools, separated from each other by baffles made of rock boulders. The purpose of this study was to analyze water surface profiles for fish ladder at specific values of flow rates. The paper presents the results of hydraulic calculations under the conditions of constant flow rate based on the concept of a minimum specific energy. According to this method, water flow through boulders is critical. Thus, it does not take into account head losses, which are hard to estimate and which are the integral part of typical calculation methods, e.g. the use of equations to determine the flow rate of a weir. An additional advantage of this method is that there is no need to assume the flow pattern of one specific weir. Verification calculations of the water depths were conducted using the HEC–RAS software, under an assumption of an one-dimensional steady water flow. Water depths in the fish ladder, calculated using both methods, were similar, despite the adopted different calculation concepts, and can be used in ichthyologic analyses.

Abstract Background Vacuolar sorting protein 35 (VPS35), a key component of the retromer, plays an essential role in selectively retrieval of transmembrane proteins from endosomes to trans-Golgi networks. Dysfunctional retromer is a risk factor for neurodegenerative disorders, including Alzheimer’s disease (AD). Microglial VPS35 deficiency is found in AD patients’ brain; however, it remains unclear if and how microglial VPS35-loss contributes to AD development. Methods We used mice with VPS35 cKO (conditional knockout) in microglial cells in 5XFAD, an AD mouse model. The AD related brain pathology (Aβ and glial activation), behavior, and phagocytosis of Aβ were accessed by a combination of immunofluorescence staining analyses and neurological behavior tests. Results A decrease in learning and memory function, but increases in insoluble, fibrillar, and plaques of β-amyloids (Aβ), dystrophic neurites, and reactive astrocytes are observed in microglial VPS35 deficient 5XFAD mice. Further examining microglial phenotype demonstrates necessity of microglial VPS35 in disease-associated microglia (DAM) development and microglial uptake of Aβ, revealing a tight association of microglial Aβ uptake with DAM development. Conclusions Together, these results uncovered a mechanism by which microglial VPS35-deficiency precipitates AD pathology in 5XFAD mice likely by impairing DAM development and DAM mediated Aβ uptake and clearance, and thus accelerating the cognition decline.

The article discusses the amplitude-frequency response of a viscoelastic body of the dam type, under steady-state forced harmonic vibrations. An important factor is the determination of the number of frequencies and resonance peaks that arise in the process of harmonic effect of the water body on the dam. The use of the finite element method (FEM) for the numerical solution of dynamic problems allows, by expanding the solution in terms of eigenmodes and frequencies, to reduce the original problem to a system of separated linear integro-differential equations with respect to the sought parameters of generalized functions. The process of the influence of viscoelastic properties of the dam material on the resonance curves that arise under harmonic loads of different frequencies at different dimensions of the foot of the dam is investigated. The analysis of the curves of the amplitude-frequency responses of a dam-type viscoelastic body, under steady-state forced harmonic oscillations, showed that the occurrence of resonance peaks depends on the viscoelastic properties of the dam body and the dimensions of the foot of the dam. The main resonance peaks occur at frequencies less than the sixth eigenfrequency, as a result of which a further increase in the number of eigenmodes in the expansion does not introduce any significant changes in the amplitude of the distribution of resonance curves of the amplitude-frequency response of the dam.

Determination of seismic wave incidence angle is a critical step in performing seismic oblique incidence analysis of dams. However, for structures with complex dynamic responses, such as dams, it is difficult to derive the incident angle by traditional mathematical methods. For this reason, this paper proposes a method for determining the seismic wave incidence angle based on the dynamic response of the dam. The model calculates the dynamic response of the dam under different incidence angles of seismic waves, establishes the mapping relationship between the dynamic response and the incidence angle by using a hybrid particle network, and performs feature screening to obtain the optimal inversion features by the SHAP method, and then constructs the optimal inversion model. The results show that there is a significant correlation between the dynamic response of the dam body and the incident angle, the correlation coefficients of the model are all greater than 0.96, and the average absolute percentage errors are less than 5 %, which proves that the model can effectively invert the incident angle. The method can also be applied to the seismic safety analysis of other structures, providing a new way to determine the seismic wave incidence angle. [ABSTRACT FROM AUTHOR]

Recovering structures from images with 180 ∘ or 360 ∘ FoV is pivotal in computer vision and computational photography, particularly for VR/AR/MR and autonomous robotics applications. Due to varying distortions and the complexity of indoor scenes, recovering flexible structures from a single image is challenging. We introduce OmniSRNet, a comprehensive deep learning framework that merges distortion-aware learning with bidirectional LSTM. Utilizing a curated dataset with optimized panorama and expanded fisheye images, our framework features a distortion-aware module (DAM) for extracting features and a horizontal and vertical step module (HVSM) of LSTM for contextual predictions. OmniSRNet excels in applications such as VR-based house viewing and MR-based video surveillance, achieving leading results on cuboid and non-cuboid datasets. The code and dataset can be accessed at https://github.com/mmlph/OmniSRNet/. [ABSTRACT FROM AUTHOR]

Pensacola Dam, operated by the Grand River Dam Authority (GRDA), is a multiple-arch buttress dam constructed in 1940. The dam has little or no existing geophysical reports on the integrity of the dam foundation rock and even less knowledge at depth. Visual inspection indicated evidence of seepage at some arches of the dam. As a pilot study, we conducted a suite of geophysical surveys inside two arches (Arch-16 and Arch-17) and a part of the downstream berm to characterize the dam foundation rock, delineate seepage zones, and identify the most appropriate geophysical methods for temporal monitoring of the dam’s conditions. The geophysical methods included electrical resistivity tomography (ERT), self-potential (SP), multichannel analysis of surface waves (MASW), compressional (P)-wave refraction, and shear (S)-wave reflection. Water samples were collected for geochemical analysis to investigate the source of the seepage flow inside Arch-16. The geophysical results characterized the dam foundation rock into an unsaturated limestone and chert overlying a water-saturated limestone and chert. The ERT profiles indicated that groundwater is rising inside the arches and significantly dropping under the downstream berm, which can be due to the uplift pressure beneath the dam base. Zones of high seepage potential were detected near the buttress walls of the two surveyed arches, which may be related to previous blasting, excavation of the dam foundation, concrete placement, or improper grouting. The geochemical analysis of water samples taken from the artesian wells inside Arch-16 and the Grand Lake revealed different chemical compositions, suggesting that the source of water could be a mixture of groundwater and lake water or lake water interacting with rock and reaching the surface through fractures; however, more sampling and further analysis are required to ascertain the source of the seeps. This study showed that the ERT, SP, and S-wave reflection methods have effectively characterized the dam foundation rock and seepage zones beneath the arches. The study provided a better understanding of the conditions of the dam foundation rock, evaluated the utilized geophysical methods, and determined the optimum geophysical methods that can be used for the characterization and monitoring of the subsurface conditions along the entire length of the dam. In this study, we have demonstrated that the integration of effective geophysical surveys and geochemical analysis yielded optimum results in solving a complex dam safety problem. This strategy promotes the best practice for dam safety investigation.

The Xiaolangdi Dam is a key project for the control and development of the Yellow River. It bears the functions of flood control, controlling water and sediment in the lower reaches, ice prevention, industrial and agricultural water supply, power generation, and so on. Its safety is related to people’s life and property safety and local economic and social development. It is of great significance to carry out comprehensive and regular deformation monitoring for dams since the deformation is an important evaluation index for dam safety. Interferometric Synthetic Aperture Radar (InSAR) technology has been a rapidly evolving technology in the field of space geodesy in recent years. It offers advantages such as high monitoring precision, extensive coverage, and high monitoring point density, making it a powerful tool for monitoring deformations in hydraulic engineering projects. Based on Sentinel-1 data covering the Xiaolangdi Dam from September 2020 to November 2022, the PS-InSAR technique was used to obtain the surface deformation of the Xiaolangdi Dam, and reservoir water level data on image acquisition dates were obtained for joint analysis. The results show that there is a large deformation in the center of the dam crest of the Xiaolangdi Dam, while both sides of the slope and downstream dam foot are relatively stable. The time series deformation of the dam body is closely related to the reservoir water level change. When the water level increases, the dam body tends to deform downstream; when the water level decreases, the dam body tends to deform upstream. The deformation and water level of the Xiaolangdi Dam exhibit a clear negative correlation. There is no significant cumulative deformation on the dam slopes or at the base of the dam. However, cumulative deformation occurs over time in the central area of the dam’s crest. The deformation process at the central area of the dam’s crest follows a continuous and non-disruptive pattern, which is consistent with the typical deformation behavior of the Xiaolangdi earth–rock dam structure. Therefore, it is judged that the current deformation of the Xiaolangdi Dam does not impact the safe operation of the dam. InSAR technology enables the rapid acquisition of high-precision, high-density deformation information on the surfaces of reservoir dams. With an increasing number of radar satellites in various frequency bands, such as Sentinel-1 and TerraSAR-X, there is now an ample supply of available data sources for InSAR applications. Consequently, InSAR technology can be extended to routine monitoring applications for reservoir dam deformations, especially for small and medium-sized reservoirs that may not be equipped with ground measurement tools like GNSS. This holds significant importance and potential for enhancing the safety monitoring of such reservoirs.