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Internet of Things (IoT), sensor technologies, and low-power long-range wide area network (LoRaWAN) protocols are crucial to reducing water wastage during storage and distribution. This letter proposes a LoRa-based automatic water pump for overhead tanks in domestic and public water services. This research uses an ESP32 LoRa IoT platform for gateway and wide area network communication and the JSN-SR04T sensor for water level monitoring. This IoT framework is integrated with mobile applications and a web server for the real-time monitoring and control of water pumps. In fully automated mode, the LoRa gateway coordinated the control of the water pump depending on the pre-configured water level during installation. In semi-automated mode, users can control the water pump with the mobile application or web server. The developed framework is tested in different environments and verified the efficacy and performance of LoRa in terms of energy consumption, RSSI, SNR and distance of communication from the host node to the LoRa gateway. The research also highlighted the reduction in water consumption, and this framework potentially addresses the sustainable development goals 6 (SDG-6). [ABSTRACT FROM AUTHOR]

The topside separation system plays a pivotal role in the treatment of produced water within offshore oil and gas production operations. Due to high-humidity and salt-infested marine environments, topside separation systems are susceptible to dynamic model variations and valve faults. In this work, fault-tolerant control (FTC) of topside separation systems subject to structural uncertainties and slugging disturbances is studied. The system is configured as a cascade structure, comprising a water level control subsystem and a pressure-drop-ratio (PDR) control subsystem. A fault-tolerant H ∞ control framework is developed to cope with actuator faults and slugging disturbances. To enhance control performance in the presence of actuator faults and model uncertainties while reducing sensitivity to slugging disturbances, the fault-tolerant H ∞ control problem for the topside separation system is established as the two-player differential game problem. In addition, a Nash equilibrium solution for the fault-tolerant H ∞ control problem is achieved through the solution of the game algebraic Riccati equation (GARE). A model-free approach is presented to implement the proposed fault-tolerant H ∞ control method using off-policy reinforcement learning (RL). Simulation studies demonstrate the effectiveness of the solution. • The Fault-Tolerant H ∞ control for topside separation is framed as a two-player zero-sum game. • An active FTC scheme using optimal game Riccati solutions addresses slugging, uncertainties, and faults. • An off-policy RL-based FTC algorithm enables model-based active control without system dynamics. [ABSTRACT FROM AUTHOR]

To reveal the behavior of geosynthetic-reinforced soil (GRS) bridge approach retaining walls on highly compressible foundation soils, in this study, a GRS bridge approach adjacent to the Yangtze River was monitored for approximately 3 years during construction and post-construction. The settlement of the GRS bridge approach, the vertical earth pressure at the base of the backfill soil, and the reinforcement deformation were monitored. The monitoring points were arranged on the left and right sides of a cross-section and a longitudinal section at the mid-span. The results showed that the settlement of the GRS bridge approach was large and uneven, and the settlement rates were influenced by the water level of the Yangtze River. Due to the large and differential settlement, the distributions of the vertical earth pressure and geogrid reinforcement strain for a retaining wall constructed on highly compressible foundation soils were different from those for a retaining wall constructed on stable foundation soils. The overall GRS bridge approach performed well with large settlements, with only some minor structural problems in the facing of the retaining wall. This indicated that the flexible GRS bridge approach was a good choice when the retaining wall was constructed on highly compressible foundation soils. • Field behavior of a GRS bridge approach with large settlement was investigated. • The settlement, vertical earth pressure and reinforcement strain were monitored. • The monitoring period was about 3 years, including the construction and service. [ABSTRACT FROM AUTHOR]

Water-level reduction frequently occurs in deep reservoirs, but its effect on dissolved oxygen concentration is not well understood. In this study we used a well-established water quality model to illustrate effects of water level dynamics on oxygen concentration in Rappbode Reservoir, Germany. We then systematically elucidated the potential of selective withdrawal to control hypoxia under changing water levels. Our results documented a gradual decrease of hypolimnetic oxygen concentration under decreasing water level, and hypoxia occurred when the initial level was lower than 410 m a.s.l (71 m relative to the reservoir bottom). We also suggested that changes of hypoxic region, under increasing hypolimnetic withdrawal discharge, followed a unimodal trajectory with the maximum hypoxic area projected under the discharge between 3 m3/sec and 4 m3/sec. Besides, our results illustrated the extent of hypoxia was most effectively inhibited if the withdrawal strategy was applied at the end of stratification with the outlet elevation at the deepest part of the reservoir. Moreover, hypoxia can be totally avoided under a hybrid elevation withdrawal strategy using surface withdrawal during early and mid stratification, and deep withdrawal at the end of stratification. We further confirmed the decisive role of thermal structure in the formation of hypoxia under water-level reduction and withdrawal strategies. We believe the conclusions from this study can be applied to many deep waters in the temperate zone, and the results should guide stakeholders to mitigate negative impacts of hypoxia on aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Smart actuators have shown great potential for a range of industries, including artificial muscles, sensors, and smart devices. However, traditional actuators often suffer from small deformation and complex materials and manufacturing processes. Graphene oxide (GO) has emerged as an ideal candidate for moisture-responsive actuators due to its excellent moisture sensitivity. In this study, we present the development of a moisture-responsive actuator using a simple and straightforward approach based on a monolayer graphene oxide (GO) paper. By utilizing the different affinity of its two sides for water, the graphene oxide actuator demonstrates excellent performance in response to humidity gradients, achieving a large bending amplitude with a curvature of 3 cm−1. Furthermore, the graphene oxide actuator was used as a humidity-sensitive switch to perform on and off switch movements, demonstrating its capability for autonomous detection for real-time humidity monitoring. This work provides a new avenue for the development of moisture-responsive materials and their potential applications in the design of intelligent control systems, actuators, soft robots, artificial muscles, and switches. [Display omitted] • The paper introduces a novel moisture-responsive actuator made of a single layer of graphene oxide paper. • The actuator exploits the different water affinity of its two sides to bend in response to humidity changes. • The actuator can also function as a humidity-sensitive switch, enabling autonomous and real-time humidity detection. • The paper demonstrates the potential of graphene oxide as a material for smart actuators, sensors, and devices. [ABSTRACT FROM AUTHOR]

Hydrogen-rich water (HRW) is a beverage containing a high concentration of hydrogen that has been researched for its antioxidant, anti-apoptotic, and anti-inflammatory properties in asthma. This study investigates the potential therapeutic impact of HRW on the gut-lung axis. Using 16S rRNA and serum metabolomics, we examined changes in gut microbiota and serum metabolites in asthmatic mice after HRW intervention, followed by validation experiments. The findings revealed that HRW influenced gut microbiota by increasing Ligilactobacillus and Bifidobacterium abundance and enhancing the presence of indole-3-acetic acid (IAA), a microbially derived serum metabolite. Both in vivo and in vitro experiments showed that HRW's protective effects against airway inflammation in asthmatic mice may be linked to the gut microbiota, with IAA potentially playing a role in reducing asthmatic airway inflammation through the aryl hydrocarbon receptors (AhR) signaling pathway. In summary, HRW can modify gut microbiota, increase Bifidobacterium abundance, elevate microbial-derived IAA levels, and activate AhR, which could potentially alleviate inflammation in asthma. [Display omitted] • Hydrogen-rich water alleviates airway inflammation in asthma. • Hydrogen-rich water partially reverses gut microbiota imbalance in asthmatic mice. • Hydrogen-rich water regulates the level of microbial-derived tryptophan metabolite IAA via gut microbiota. • IAA activates aryl hydrocarbon receptor and reduces IL-13-induced BEAS-2B cell injury. [ABSTRACT FROM AUTHOR]

A theoretical study was conducted to investigate the cross-sectional configurations and the tensile forces of an air-inflated rubber dam anchored on the sidewall of the rigid base. A series of large-scale model tests were conducted using rubber dam models with a cross-sectional perimeter of 1.0 m and a length of 8.5 m. The results obtained from the analytical solutions agree well with those obtained from model tests. It is found that there is an optimum height of the rubber dam, especially for larger anchor depth with the increase of the inflated air pressure. The smaller the anchoring depth the higher the optimum inflated air pressure. The contact length between the rubber dam and the rigid base gradually decreases with the increasing inflated air pressure. The greater the anchor depth, the faster the contact length decreases to zero. Generally, the tensile force linearly increases with the increase of the normalized air pressure and the decrease of the anchor depth. • Theory was derived to calculate an air-inflated rubber dam anchored on the sidewall of rigid base. • A series of large-scale model tests were conducted to verify accuracy of the theoretical model. • Effects of upstream water levels, inflated air pressures and anchor depths were analyzed. [ABSTRACT FROM AUTHOR]

This study aimed to explore the spatial heterogeneity and risk factors for dental caries in 12-year-old children in Shanxi province, China. The data encompassed 3,721 participants from the two most recent oral health surveys conducted across 16 districts in Shanxi Province in 2015 and 2018. Eighteen specific variables were analyzed to examine the interplay between socioeconomic factors, medical resources and environmental conditions. The Geo-detector model was employed to assess the impacts and interactions of these ecological factors. Socioeconomic factors (Q = 0.30, P < 0.05) exhibited a more substantial impact compared to environmental (Q = 0.19, P < 0.05) and medical resource factors (Q = 0.25, P < 0.05). Notably, the urban population percentage (UPP) demonstrated the most significant explanatory power for the spatial heterogeneity in caries prevalence, as denoted by its highest q -value (q = 0.51, P < 0.05). Additionally, the spatial distribution's heterogeneity of caries was significantly affected by SO 2 concentration (q = 0.39, P < 0.05) and water fluoride levels (q = 0.27, P < 0.05) among environmental factors. The prevalence of caries exhibited spatial heterogeneity, escalating from North to South in Shanxi Province, China, influenced by socioeconomic factors, medical resources, and environmental conditions to varying extents. [ABSTRACT FROM AUTHOR]

Dongting Lake wetland provides important ecosystem functions for water regulation and biodiversity protection. However, the construction of the Three Gorges Dam has seriously affected the wetland hydrology and landscape. Therefore, it is of great significance to study the landscape dynamics of Dongting Lake wetland and its response to hydrological changes. Based on GEE cloud platform, this paper will obtain the long-term landscape dynamic changes of Dongting Lake wetland and analyze the influence of changes of multi-period water conditions on wetland landscape. The results show that, 1) From 1985 to 2020, the typical vegetation area of Dongting Lake wetland changed obviously on the whole lake scale. The evolution of wetland landscape pattern mainly occurred in East Dongting Lake, west of South Dongting Lake and north of West Dongting Lake. 2) According to the M-K method, the water level data of Dongting Lake showed a sudden change in 2003. This led to the decline of the annual water level of Dongting Lake and the decline of the water level during the wet season and retreating season. 3) The main hydrological variables affecting the change of the area of C. brevicuspis (Carex brevicuspis) and P. australis (Phragmites australis) in Dongting Lake wetland are the mean water level and minimum water level in wet season, and the mean water level, the minimum water level and the maximum water level in retreating season. This study can be used as a theoretical foundations to protect and restore the wetlands of Dongting Lake and manage the Three Gorges project. [ABSTRACT FROM AUTHOR]

The construction and operation of the Three Gorges Dam, the world's largest dam, has provided important support for national economic development and drinking water safety. However, the dam's construction has had a non-negligible impact on the ecosystem condition of lake wetlands in the middle and lower reaches of the Yangtze River, which has become a significant theme in recent scientific researches and policy works. Although previous studies have carried out detailed assessments of the relationship between the Three Gorges Dam and downstream lake wetland ecosystems, there has not been a comprehensive discussion. Based on the bibliometric method and the systematic collation of related research, this paper comprehensively reviewed the research progress and hot topics of the river-connected lakes in the middle and lower reaches of the Yangtze River under the influence of the Three Gorges Project. The results show that the number of related studies continued to grow during the study period, involving multiple research fields. The research hotspots focused on five fields: schistosomiasis, remote sensing monitoring of the landscape, water quality, water level and sediment. The disturbance of the Three Gorges Dam on lake water level, landscape heterogeneity and habitat quality may be the focus of further research. In addition, this study presents challenges and recommendations for future research directions. This paper aims to provide a constructive reference for the management of the Three Gorges Dam and the conservation and restoration of lake wetland ecosystems. [ABSTRACT FROM AUTHOR]

In this study, an automatic control technology for liquid-hydrogen zero boil-off was developed to improve the long-term storage capability of small-scale liquefaction systems. An innovative system capable of monitoring both the pressure within the heat pipe and the pressure within the LH 2 vessel was developed. This innovative approach ensures continuous efficiency and reduces downtime, significantly improving the overall performance of the hydrogen liquefaction process. The optimal conditions for automatic control were obtained through a cycle test in ON/OFF mode. In addition, experimental investigations were conducted sequentially to investigate the effect of the water level of liquid hydrogen such as 1st section, 2nd section and 3rd section of LH 2. As a result, these experiments successfully demonstrated zero boil-off of liquid hydrogen for long-term storage in the vessel, corresponding to a constant value in the liquid level meter in each section. The velocity of stabilization from the temperature and pressure perspectives in the vessel increased, and the entire cryocooler cycle time was significantly influenced by the amount of liquid hydrogen produced. • An automatic control technology for liquid-hydrogen zero boil-off was developed. • The pressure data on the liquid hydrogen vessel and heat exchanger were determined. • The effect of the water level of liquid hydrogen was investigated. • Experiments demonstrated zero boil-off of liquid hydrogen for long-term storage. • The entire cryocooler cycle time was influenced by the amount of liquid hydrogen. [ABSTRACT FROM AUTHOR]

• Spider community composition changed during the rice growing season. • The rice field development generally decreased the number of horizontal web-building spiders and captured detritivorous prey. • Species identity and species traits of spider as well as environmental factors affect prey capture by web-building spiders. Understanding the effects of microhabitat changes on arthropod predator communities and their prey in agroecosystems is essential for field management and biocontrol. Few studies have investigated the trait composition of web-building spider communities in rice ecosystems. Here, we examined how temporal changes during the rice field development affect the abundance and traits of orb-web spiders, and how these effects consequently influence captured prey number and prey composition in irrigated rice ecosystems in southern Thailand. We used structural equation models to evaluate direct and indirect, spider-mediated effects of rice field development on captured prey numbers in each different guild. We found that the number of horizontal web-building spiders decreased during the rice field development, whereas there was no significant change in number of vertical web-building spiders. The number of captured detritivorous insects was positively related to the numbers of horizontal and vertical web-building spiders, while phytophagous insects and others were positively related only to the numbers of vertical web-building spiders. Moreover, the prey number captured by vertical web-building spiders seems to be indirectly increased through the decreasing number of horizontal web-building spiders in the late rice season. A fourth-corner analysis showed that spider species identity, spider traits (web type, web height and web diameter), vegetation height, and water level generally influenced the prey captured by web-building spiders. Horizontal web-building spider species with lower web placement during the flooding phase captured high numbers of detritus-feeding insects, while vertical web-building spider species with higher web placement captured high numbers of rice pests, predators and others. Our results suggest that the field development acted as an environmental factor that determined the species identity and traits of web-building spider communities. The findings of this study can help to predict the ecosystem services provided by the web-building spider community in rice ecosystems. [ABSTRACT FROM AUTHOR]

In recent decades, there have been individual cases of damage to geotextile filters due to clogging by flocculated ochre products. This process is defined as ochre clogging and has been extensively explained in recent theoretical studies (Tophoff et al., 2022). Several revetments of tidally influenced German North Sea estuaries have been damaged due to a severe reduction in the permeability of geotextiles. Therefore, experimental investigations of granular and geotextile filter constructions were carried out to better understand filter clogging. The investigations reproduce a revetment section at a scale of 1:1. For this purpose, the clogging process in the fluctuating water level or clogging zone was reproduced as a purely chemical iron precipitation. Ten short-term tests (10 h) and one long-term test (50 h) were carried out in total. The tests show that the process involves internal clogging and that the iron precipitates adhere immovably to the filter structure, reducing the pore space and permeability of the filter. This process is considered less problematic for granular filters. A reduction in permeability was measured in some cases for geotextile filter designs. Different geotextile material parameters appear to influence the iron ochre clogging tendency. • Ochre clogging has led to individual revetment damages in tidally influenced waterways. • Chemical iron precipitation in filters can be reproduced in the laboratory. • Iron precipitation is partly accompanied by a reduction in filter permeability. • Iron precipitates are physicochemically bound to the filter surface. • Ochre clogging products contain ultra-fine particles from the filter environment. [ABSTRACT FROM AUTHOR]

The importance of satellite altimetry for monitoring inland water bodies is increasing, with the increasing need for fresh water. With the addition of the Sentinel-6 Michael Freilich (MF) in 2020 to the satellite altimetry record, we have parallel high- and low-resolution inland water observations. In this study, we validate Sentinel-6MF low- and high-resolution lake water levels, as determined with a state-space model, with data from 124 gauges in 85 lakes (of size > 20 km2) from the United States, Canada, Sweden, and Australia. Furthermore, we estimate the scatter of the observations at 1330 globally distributed lakes. We address the difference in performance when using a physical (ocean) and empirical (OCOG) retracker. Using the 124 gauges as ground truth, we determine a best-case unbiased root mean squared error (u-RMSE) of 6.4 cm for Sentinel-6MF, when using the high-resolution mode and the OCOG retracker. The u-RMSE is between 6.4 and 12.3 cm when correcting for ice-covered lakes, and 15.6 to 31.3 cm for all data, depending on retracker and resolution mode. The corresponding median standard deviation of water surface elevations per transect from the 1330 lakes is 3.5 cm and 8.1 cm for high and low-resolution OCOG-based water levels, respectively. The corresponding median standard deviation of Sentinel-3A/B OCOG (enhanced measurement, 20 Hz mode, baseline-3/4) is 5.9 cm and 6.0 cm. We find a lower u-RMSE and standard deviation for high-resolution data, and the ability to observe more lakes, compared to the low-resolution mode. From this, we see that Sentinel-6MF yields valid estimates of the water surface elevation, including smaller lakes, and would provide additional value to future water level monitoring via remote sensing. [ABSTRACT FROM AUTHOR]

• The flow characteristics of vertical slot fishways at different slopes (1.5%, 3.0%, 4.5%, 6.0%) were systematically studied. • The turbulence and energy dissipation in a fishway increase with increasing slope. • The distribution of vorticity shows little variability with increasing slope but may interfere with the passage of fish through the vertical slot. • An increase in water depth has no significant effect on the flow characteristics in the pool. The effects of a vertical slot fishway slope (with slope values from 1.5% to 6%) on a flow field are numerically investigated, using a re-normalization group k – ε model. The distribution of the velocity, turbulence kinetic energy (TKE), average energy dissipation rate per unit volume (E), and vorticity for different slopes are systemically explored. The results indicate that, with an increase in slope, the appearance of downward flow in conjunction with an increase in vertical velocity results in three-dimensional flow characteristics. The recirculation region in H s , at a 6.0% slope, was 20.9% less than that at a 1.5% slope. Meanwhile, the flow velocity in the vertical slot region grew with increasing slope, which would limit the passage of fish with burst speed lower than the velocity in the vertical slot region. The TKE and E may locally exceed the threshold at larger slopes. Furthermore, vorticity distribution shows little variability with increasing slope, but may interfere with the equilibrium of the fish in the vertical slot region. In addition, the change in water level has little effect on the flow field, which is changed by the increase in slope. These findings can aid vertical slot fishway designs especially in terms of the efficiency of fish passage. [ABSTRACT FROM AUTHOR]

Water, a critical resource, suffers from significant losses due to leakages in Water Distribution Networks (WDN). These losses present financial, environmental, and public health challenges. With water utility companies amassing vast amounts of data from enterprise information systems, the opportunity for data-driven leakage detection arises. With the increased use of enterprise information systems, water utility companies are generating vast amounts of data that can be valuable for predicting or detecting water leaks early and also for the development of new, automatic, and effective data-driven leak detection techniques. The presented study utilizes this data, by applying anomaly detection methods to heterogeneous time-series data from various components of the WDN in Slovakia. Our results demonstrate that components of the network, such as measured power consumption, water source temperature, and water source levels show significant positive associations with faults in the Water Distribution Network. [ABSTRACT FROM AUTHOR]

The purpose of the study was to develop the method of using unmanned aerial vehicles (drones) to map fish fauna habitats in a large lowland river. The intention was to acquire and process spatial data to implement it in the Mesohabitat Simulation system (MesoHABSIM). At three different water levels, remote sensing data was acquired by unmanned aerial vehicles on the lower Vistula River section. In parallel, depths and velocities of flowing water were measured. Orthophotomosaics were created from the collected images, overlaid with depth and velocity observations to identify hydromorphological units. Maps of fish fauna habitats under different water levels were obtained. The application of the developed procedure algorithm proved successful in habitat mapping studies on a large, deep river with opaque water. The significance of using orthophotomosaics presenting the river under well-defined flow conditions was proven to achieve high accuracy in mapping habitat conditions and reduce errors in habitat usability analyses by fish community. The superiority of using unmanned aerial vehicles over other methods of collecting data on river habitats and depth and velocity measurements using the Acoustic Doppler Current Profiler (ADCP) method in large rivers with non-clarity water was confirmed. In addition, it was pointed out that drones provide high-resolution images under well-defined flow conditions, which are impossible to obtain using available cartographic materials. The validity of using the incomparably cheaper ADCP technology relative to laser technology, whose application in rivers with opaque water is very complicated, was also confirmed. [ABSTRACT FROM AUTHOR]

The natural environment of the Eemian Interglacial (MIS 5e) and Early Vistulian (MIS 5 d-a) in many areas in Central Europe is still insufficiently and fragmentarily known. Therefore, after the discovery of an almost complete skeleton of the Eemian Stephanorhinus kirchbergensis (Jäger, 1839) in outcrop of palaeolake sediments near Gorzów Wielkopolski (GW site, GS3 profile), a multi-proxy analysis was conducted for a precise recognition of the environmental and climate changes taking place before, during and after the life of this individual. Comprehensive palaeobotanical investigations of sediments of two palaeolakes lying above each other were performed palynological analysis including NPPs and algal analysis, plant macroremains studies (including wood fragments), as well as palaeozoological analyses of the Cladocera, Chironomidae and Coleoptera. The picture of changes in the environment and climate obtained thanks to the performed analyzes presented in a short way looks as follows. The end of the Wartanian Glaciation (MIS 6) was characterised by the dominance of herbaceous vegetation. Along with the gradually changing climatic conditions, the landscape of the Eemian Interglacial was dominated in sequence by birch, pine, oak (the so-called First Thermal Optimum), hazel forests with linden, hornbeam (Second Thermal Optimum) with a rarely recorded dry oscillation, then spruce with fir and again pine forests. The "older Eemian lake" during this time changed from deep, cold, oligotrophic and carbonate to shallower, cold waters with higher trophy, then deeper with lower trophy, again shallower with peats and dystrophic conditions and finally became terrestrial. The age of the post-Eemian part of the GS3 profile was reinterpreted, recognizing OSL dating as more reliable than radiocarbon dating, determining the age as Early Vistulian. Subsequent stages of this part of profile were characterised by significant cooling and intense development of heaths and peatbogs (MIS 5d), double return of pine and birch forests separated by intra-interstadial cooling (MIS 5c), recooling with dominant herbaceous plants (MIS 5b) and last warming with birch forests (MIS 5a). The "younger Early Vistulian lake" was formed with the rising of the water level. It was shallow, cold, low-trophic, with the water heating up in the summer, which caused trophic increases. Water levels fluctuated. With the progressing terrestrialization, oligotrophy appeared. Each of used proxies reconstructs a fragment of palaeoenvironmental changes on land and/or in the reservoir, registering climatic events on both regional and local scales. However, only the combination of all results allows for a full picture of natural changes. [ABSTRACT FROM AUTHOR]

This article presents the results of malacological and isotope studies on lacustrine sediments from the Eemian interglacial site in the Piła (north-western Poland). Twenty species of molluscs were found in the analysed sediments. Changes in the taxonomic composition and the quantitative structure of malacofauna in the profile allowed distinguishing five types of assemblages corresponding to different phases of the lake's evolution. Ratios of oxygen and carbon isotopes (δ18O and δ13C) reflecting changes in the lake water composition were measured in shells of two predominating snail species, Valvata piscinalis (Müller, 1774) and Bithynia tentaculata (Linnaeus, 1758), and in opercula of Bithynia tentaculata. Significant variability in isotope contents was noted for shells in individual profile sections and between analysed taxa. The results of malacological and isotope studies were supplemented with lithological, stratigraphical and palynological data. On this basis, the sediments age was determined (optimal and suboptimal phases of the Eemian interglacial). Environmental changes of paleolake have been also reconstructed. The analysed sediments were initially deposited in the coastal, periodically drained zone of the reservoir. The younger part of the sequence represents the shallow part of the littoral zone of the permanent water body. The malacological and isotope data also allowed distinguishing two phases of increased water level in the reservoir, and changes in its trophic state probably generated by climatic factors. [ABSTRACT FROM AUTHOR]

Farmers in a particular area of the Southern Philippines have confirmed that droughts have affected their rice farms, compelling them to lessen their cropping annually until enough water resources become available. This influenced them to seek alternative irrigation techniques. This study creates a system that implements an alternate wetting and drying technique-based irrigation scheduling to cover a whole rice cropping season through water level and soil moisture sensing. The system is available to three rice growth varieties; short, medium, and long. System development includes implementing SMS for notification, a low-power wide area network, and utilizing an IoT dashboard for data visualization. [ABSTRACT FROM AUTHOR]

Understanding and predicting water level rise is crucial for effective water resource management, flood control, disaster risk reduction, and adaptation to climate change. This study utilize the use of Support Vector Regression Machine (SVRM) models in predicting the water level of Mandulog River in the Philippines. To evaluate its predictive capability, two data architectures, various kernels, and parameters were examined to find the optimal configuration. Multiple kernels were compared for accurate pattern discovery, and parameter selection was performed to enhance predictive accuracy. The SVRM models achieved the lowest Mean Average Percentage Error (MAPE) of 2.186%, Root-Mean Squared Error (RMSE) of 0.00601 during the dry season, and MAPE of 2.226% and RMSE of 0.00602 during the rainy season. Both models were deemed suitable for watershed level forecasting. [ABSTRACT FROM AUTHOR]

To examine the performance of Artificial Neural Networks (ANNs) in predicting the water level of a watershed three days ahead of time, this study evaluated eighteen ANN models with different combinations of training algorithms and activation functions. The two best models corresponding to the two major climate seasons in the Philippines were: for the rainy season; it was the Resilient Propagation with Leaky ReLU which produced MAPE and RMSE of 6.731 and 0.0098, respectively; for the dry season, it was the Scale Conjugate Gradient with Leaky ReLU which produced MAPE and RMSE of 7.871 and 0.01045, respectively. [ABSTRACT FROM AUTHOR]

• A coupled model is proposed integrating a 2D double layer-averaged model for reservoir and a 1D model for bottom tunnel. • High water level, small cover layer thickness, short tunnel length and steep tunnel slope favour the occurrence of sediment flushing. • Low water level, large cover layer thickness, long tunnel length and gentle tunnel slope are more likely to cause tunnel blockage. Sediment flushing through a bottom tunnel is one of the most effective methods to alleviate reservoir sedimentation. However, the multi-physical hydro-sediment-morphological processes of reservoir sediment flushing through an initially covered bottom tunnel intake have remained poorly understood, and a physically enhanced and practically viable mathematical model is required. The present study uses an integrated model to resolve sediment flushing through an initially covered bottom tunnel intake. The proposed model couples a two-dimensional double layer-averaged model for the reservoir with a one-dimensional model for the bottom tunnel by means of numerical fluxes calculations at the inner boundary. The governing equations are solved synchronously using a well-balanced finite volume method. Several parameters related to boundary resistances and sediment exchange flux need to be determined for model closure. The model is tested against data from a series of physical experiments on reservoir sediment flushing, with sound agreement achieved between computed and measured scour hole geometries. Moreover, the present model successfully predicts the occurrence of tunnel blockage. The results prove that reservoir sediment flushing is best accomplished for high reservoir water level, small cover layer thickness, short tunnel length and steep tunnel slope. The present model facilitates reservoir design and operation to help preserve reservoir capacity. [ABSTRACT FROM AUTHOR]

Fish entrainment from reservoirs to downstream rivers by various water release structures may result in serious consequences for reservoir ecosystems. This study proposed an integrated modeling approach for determining fish entrainment risk zones and suitable reservoir regulations. The modeling approach combines hydrodynamic and fish risk assessment modeling with using fuzzy rules set defined by expert knowledge in fish ecology. We applied this modeling approach in the Maling Reservoir in China, where fish entrainment in the reservoir has been observed in the turbine, spillway, and irrigation system. Percocypris pingi (Tchang, 1930) and Onychostoma simum (Sauvage & Dabry de Thiersant, 1874), representing the main and protected fish species, were selected as target fish species. Five reservoir operation schemes were investigated under normal and designed water levels. The modeling results suggest that the fish entrainment risk for protected fish species (Onychostoma simum) is higher than that for the main fish species (Percocypris pingi). The results indicate a ranking of the fish entrainment risk from high to low in the following scenarios: with all spillways in operations, with one spillway in operation, with intakes in operation, with an irrigation system in operation, and with intakes and the irrigation system in combined operations. In addition, under normal and designed water levels, dead fish entrainment zone areas and percentages were extremely low compared to the entire forebay of the reservoir. These results indicate that the operation of the Maling Reservoir does not affect the ecological status of fish. These findings are generally applicable to any fish species in reservoirs that balance reservoir operations and ecological protection of fish, and could assist reservoir managers in making informed decisions on how to mitigate and compensate for fish entrainment. [ABSTRACT FROM AUTHOR]

Hyaluronic acid (HA) and chondroitin sulfate (CS) are polydisperse glycosaminoglycans (GAGs),which have important applications as health care products and drugs in skin beauty and arthritis prevention. Enzymatic synthesis is a significant strategy to obtain oligosaccharides and polysaccharides with uniform chain length and well-defined structure. However, the limitations of glycosyltransferase, such as low expression, poor stability, and difficulty in reuse, greatly restrict its application in large-scale commercial production. In this study, we constructed the expression system for hyaluronic acid synthase PmHAS and chondroitin synthase KfoC to obtain the enzyme with high expression level and good water solubility. Subsequently, we screened and optimized several highly biocompatible metal-organic frameworks (MOFs) to immobilize two glycosyltransferases efficiently. The resulting enzyme@MOF composite can catalyze the synthesis of hyaluronic acid and chondroitin oligosaccharides/polysaccharides in quantitative yield. Meanwhile, the supramolecular interactions between enzyme and hydrophilic MOFs confer satisfactory stability, durability, and reusability on immobilized PmHAS and KfoC. [Display omitted] • Immobilize glycosyltransferases in metal-organic framework. • One-step self-assembly method for constructing immobilized enzyme microreactors. • Efficient synthesis of glycosaminoglycan using enzyme@MOF composites. • The catalytic stability of glycosyltransferase was improved. [ABSTRACT FROM AUTHOR]

• Water deficit exposed plants exhibited higher level of oxidative marker production. • Salicylic acid application help to revive stressed plants through triggered the antioxidative mechanism. • Salicylic acid influenced the Bacoside-A amount with integration of water deficit. Salicylic acid (SA), an eminent stress tolerance phytohormone, assists plants in dealing with abiotic stress. A pot experiment was carried out to substantiate the SA's ability to protect the medicinal herb Bacopa monnieri (L.) from exposure to water deficit. Diverse concentrations of SA (50, 75, 100, and 125 mg/l) were applied to plants as a foliar spray along with varied water levels based on reduced irrigation, WD1 (twice a week), and WD2 (once a week) against WW (once a day), with the first spray being applied after one week of water deficit treatment and the second one month later. The pool data for 2021 and 2022 demonstrated the resilience propensity of SA against water deficit in terms of oxidative markers detoxification (H 2 O 2 and MDA) via evoking the antioxidative mechanism of plants. The activity of antioxidants (SOD, CAT, GPOX, and APOX) and amount of non-enzymatic antioxidants (ascorbic acid, total phenolics and, flavonoid) including osmolytes (proline and total soluble sugar) was upsurged after SA (75 mg/l conc.) administration under both stressed and non-stressed plants. Additionally, stressed plants also revealed a recovery in their relative water content with intensifying the membrane stability index. Besides that positive repercussion in terms of medicinally bioactive compound (bacoside-A) content was also achieved with 75 mg/l conc. of SA foliar spray in addition to WD2. Conclusively, the present investigation unraveled the attainment of SA to ameliorate the B. monnieri (L.) under water deficit stress at moderate doses (up to 100 mg/l) by boosting their deterrence mechanisms through counterbalance of the physio-biochemical attributes. [ABSTRACT FROM AUTHOR]

In Mongolia, overuse and degradation of groundwater is a serious issue. The authors have recently applied a process-based eco-hydrology model, NICE (National Integrated Catchment-based Eco-hydrology) to urban and mining hubs to explicitly quantify spatio-temporal variations in water availability. In this study, NICE was scaled up to the total of 29 river basins in the entire country. The model simulated the effect of past climatic change and human activity on water resources during 1980-2018 there. The model reasonably reproduced observed river discharge with a maximal value during summer rainfall seasons. The simulation also revealed heterogeneous distributions of hydrologic budget and its response to climatic and anthropogenic disturbances. In addition, the authors detected hot spots of groundwater degradation by anthropogenic activity in the national scale. Analysis of relative contribution of environmental factors further clarified the characteristics in these areas and quantified spatio-temporal trends in groundwater level due to the effects of changes in precipitation and various water uses. Generally, the result showed changes in precipitation had a large effect on changes in groundwater levels until 2000. In contrast, the model clarified human activities have recently had a large impact on groundwater level changes. This trend was particularly conspicuous in river basins with urbanization and mining development such as Orkhon, Kharaa, Tuul, Galba, Ongi, Altain Uvur Govi, and Taats River Basins. This methodology is powerful to resolve future competition for water resources in areas with fewer inventory data that could potentially trigger conflicts between urban, mining, industry, herders and local communities. [ABSTRACT FROM AUTHOR]

In recent years, the degradation of palm groves due to the rise of hypersaline groundwater has increased. This research aims to assess the hydraulic connectivity status between the Oued Righ channel and the adjacent aquifer. For this purpose, a piezometric network with 20 monitoring wells was installed, and the channel's water and bottom levels were measured in April and September of 2019 at 12 gauging stations, then the soil samples of the banks and the bottom were collected from the channel. The results showed the predominance of silty loam formation, which has reflected the weakly values of hydraulic conductivity of the clogging layer, with values ranging from 5.51 x 10-5 to 6.74 x 10-6 m/s, and according to the results of the hydraulic head differences between the channel and phreatic water for both periods, we found two types of water return statuses: hydraulically connected in the sections (22.5-25.5 km and 36-42.5 km), and hydraulically disconnected in the sections (23.5-24.5 km and 38.5-42 km). The study's findings are critical for water resources management, in order to preserve palm groves' wealth, which is the most important economic resource for the population. [ABSTRACT FROM AUTHOR]

The rational surface water resources evaluation and research is a prerequisite for the development, utilization, and protection of water resources. The amount of water resources is an important factor related to the socio-economic development and ecological security of a region. Accordingly, this paper aims to establish a suitable water quality and quantity coupling model based on the current situation of river pollution in the Shenfu section of the Hunhe River basin, with the prediction of surface water resources as the objective function. The research compares the model simulation results with the hydrological data of Fushun No. 2 Station and Cheung Tsing Bridge Station in relevant hydrological data and observes the water quality stations in the basin. Then it sets a conversion coefficient ratio based on common indicators for water quality discrimination and converts the available amount of surface water resources in the study area. The results showed that the error between the simulated and actual measured values of the water station flow and section water level in the study area was 8%, which was within the range specified by the state. Due to water pollution, the amount of locally available water resources were reduced by 16.18% compared to the total amount of surface water resources after conversion. The research results proved that the model constructed in this study had excellent performance in the calculation and evaluation of surface water resources. [ABSTRACT FROM AUTHOR]

Arsenic is among the most critical environmental toxicants associated with many human disorders. However, its effect on type 2 diabetes mellitus (T2DM) is contradictory. This systematic review and dose-response meta-analysis aim to update information on the association between arsenic exposure and the risk of T2DM. The sample type (drinking water, urine, blood, and nails) conducted the subgroup analysis. Evaluation of the high vs. low arsenic concentrations showed a significant association between drinking water arsenic (OR: 1.58, 95% CI: 1.20–2.08) and urinary arsenic (OR: 1.37, 95% CI: 1.24–1.51) with the risk of T2DM. The linear dose-response meta-analysis showed that each 1 μg/L increase in levels of drinking water arsenic (OR: 1.01, 95% CI: 1.00–1.01) and urinary arsenic (OR: 1.01, 95% CI: 1.00–1.02) was associated with a 1% increased risk of T2DM. The non-linear dose-response analysis indicated that arsenic in urine was associated with the risk of T2DM (Pnon-linearity <0.001). However, this effect was not statistically significant for arsenic in drinking water (Pnon-linearity =0.941). Our findings suggest that blood arsenic was not significantly linked to the increased risk of T2DM in high vs. low (OR: 1.21, 95% CI: 0.85–1.71), linear (OR: 1.04, 95% CI: 0.99–1.09), and non-linear (P non-linearity =0.365) analysis. Also, nail arsenic was not associated with the risk of T2DM in this meta-analysis (OR: 1.33, 95% CI: 0.69–2.59). This updated dose-response meta-analysis indicated that arsenic exposure was significantly correlated with the risk of T2DM. • This meta-analysis evaluated the association between arsenic exposure and the risk of T2DM. • Drinking water and urinary arsenic were associated with the risk of T2DM in high vs. low analysis. • Drinking water and urinary arsenic were associated with T2DM in linear dose-response analysis. • Nonlinear dose-response analysis showed that arsenic in urine was associated with the T2DM risk. • Blood and nail arsenic levels were not significantly linked to the risk of T2DM. [ABSTRACT FROM AUTHOR]

Thermal stratification widely exists in large reservoirs, causing significant inflow-outflow temperature difference (IOTD), which goes against the downstream ecology. Reservoir optimal operation has recently been conducted to regulate the outflow temperature, while its effects for cascade reservoirs urgently needed to be illuminated. Taking the typical Xiluodu-Xiangjiaba cascade reservoirs (XXCR) as study case, this paper had built a multi-objective optimal operation model combing the non-dominated sorting genetic algorithm II (NSGA-II) and a hydrodynamic-temperature model, and the total power generation (TPG) and IOTD were simultaneously considered. The effects of different inflow discharge and global warming scenarios were analyzed. This paper showed the following: (1) The IOTD and TPG of XXCR showed a positively linear relationship with the water level of the superior Xiluodu Reservoir (XLD), instead of the inferior Xiangjiaba Reservoir (XJB). (2) The reservoir with larger water volume and depth (such as XLD) determined the thermal structure and hydropower generation in cascade reservoirs, compared with the inferior reservoir (such as XJB). (3) As the inflow discharge or air temperature increased, the slope between the IOTD and TPG in the Pareto front curve increased. The results of this paper could support the ecological operation for cascade reservoir to regulate the outflow temperature. [Display omitted] [ABSTRACT FROM AUTHOR]

• The risk of toxic metals in sediments were assessed at different depths. • Pb and cd binding to surface sediments is mainly mediated by organic functional groups. • Mineral components were mainly bound to toxic metals in the bottom sediments. • Mineral compounds (Fe, Mn), Pb, and c functional groups were unevenly distributed. • The type and sequence of toxic metal binding changed with sediment depth. The excessive accumulation of potentially toxic metals (Pb and Cd) in coastal wetlands is among the main factors threatening wetland ecosystems. However, the effects of water table depth (WTD) on the risk and binding mechanisms of potentially toxic metals in sediments remain unclear. Here, sediments from different WTD obtained from a typical coastal wetland were evaluated using a newly developed strategy based on chemical extraction methods coupled with high-resolution spectroscopy. Our findings indicated that the WTD of the coastal wetland fluctuates frequently and the average enrichment factor for Pb was categorized as minor, whereas Cd enrichment was categorized as moderate. High-resolution spectroscopy techniques also demonstrated that organic functional groups and partly inorganic compounds (e.g., Fe-O/Si-O) played a vital role in the binding of Pb and Cd to surface sediments. Additionally, mineral components rather than organic groups were mainly bound to these metals in the bottom sediments. Collectively, our findings provide key insights into the potential health effects and binding characteristics of potentially toxic metals in sediments, as well as their dynamic behavior under varying sediment depths at a microscale. [Display omitted] [ABSTRACT FROM AUTHOR]

Extremely high lead level in tap water caused by particulates has attracted increasing attention in recent years. Despite extensive research on the role of particulate Pb in water supply systems with lead service lines, little information is available on the role of particulate Pb in copper (Cu) water distribution systems. In this study, the dissolved, colloidal, and particulate lead and copper concentrations in representative prototype copper pipe water distribution systems with leaded solder joints and brass fixtures are measured. The effects of flow rate and stagnation time on metal fractionation are investigated. For each experimental scenario, all the water that stagnated inside the system is sampled to have a comprehensive understanding of lead contamination. Sampled at flow rates of 200–250 mL/s, the soluble lead and copper make up 60–96 % of the total concentration in the samples after hours of stagnation. More than half of the Pb and Cu particles are larger than 0.8 μm. Higher flow rates result in substantial increases in particulate metal concentrations but have no apparent effect on dissolved metals. The soluble and particulate copper concentrations (∼ 100–250 μg/L) both increase with stagnation time. For the case of Pb, while the particulate concentration increases (up to ∼ 40 μg/L after 12 h), the soluble concentration does not change significantly beyond 4 h; this can be attributed to the different solubilities of Pb (∼ 20 μg/L) and Cu (∼ 200 μg/L) in tap water. The results also show that particulates suspended by clean "once through" water (without prior stagnation) can lead to high levels of Pb contamination (> 10 μg/L). [ABSTRACT FROM AUTHOR]

• Floodplain conservation requires long-term knowledge of floodplain hydrology. • hyd1d provides interpolation algorithms for 1d hydraulics and gauging data. • hydflood provides extrapolation algorithms of hyd1d results into floodplains. • Together hyd1d and hydflood enable fast hydrological modelling on floodplains. • Input data, software and output are provided openly. Floodplains are environments characterized by fluctuating water levels. Spatial and temporal heterogeneity of habitat conditions driven by hydrology are the key factor for their high biodiversity because strong environmental filtering either creates favorable conditions for specialized organisms or eliminates competing generalists. hyd1d and hydflood are two R packages for simplified hydrological modelling in two large central European floodplains – along the rivers Rhine and Elbe in Germany – that enable users to simulate the dynamics of water level changes, flood extents and durations with high spatial and temporal resolution over long time periods and vast areas. They are simplified in the sense of not being based on physical equations, but they implement fast computing interpolation of 1d hydraulic data and GIS extrapolation algorithms. Annual and long-term products provide the possibility to predict the distribution of floodplain habitats. All input datasets are highly integrated into the packages and automatically updated. Computationally expensive products such as annual flood durations between 1960 and 2022 are provided as open data. The software itself is provided as open source software through CRAN and in public code repositories. With minimal efforts users can apply the software within the given conditions or integrate other river systems through data and source code contributions. [Display omitted] [ABSTRACT FROM AUTHOR]

Over the last few decades, satellite radar altimetry has developed enabling a wide range of applications, including the monitoring of lakes. As a method to measure lake water level time series, satellite radar altimetry contributes to gaps in data of in-situ networks in time and space, which is freely available, continuous, global, regular, and precise. However, depending on the location, shape, size, and surrounding environment of the lakes, the accuracy of water heights inferred from altimeters varies significantly. The accuracy of water heights also strongly depends on the quality of space-born instruments, with modern models having evolved from radar altimeters launched in the 1990 s. To determine the level of accuracy of radar altimeters, it is necessary to use ground observations of lake heights. However, the measurements performed onboard by altimeters and on the ground by water level gauges are not directly comparable because the physical properties and scaling of the measurements are completely different. In this study, we present an approach which permits realistic inter-comparison of water levels, in relation to a large lake with a large number of hydrological stations (at least 10) and the presence of at least 10 satellite measurements per month (on the example of lake Baikal), in order to provide diagnostics on the quality of the radar altimeter and statistics of the errors. [ABSTRACT FROM AUTHOR]

The momentum-conserving staggered grid (MCS) scheme to simulate shallow water flows in channels of varying width and topography is revisited in this article. Here, we modify the MCS scheme so that it can be applied to channels of arbitrary cross-section. The scheme is validated using steady analytical solutions for channels with rectangular and trapezoidal cross sections. We found that the method was capable of solving a wide variety of test cases; including subcritical, supercritical and transcritical steady flows and flows with hydraulic jumps. This MCS scheme could handle both steady and unsteady problems. In the implementation of a channel with arbitrary cross sections, the simulation depicts the time-lapse evolution of the water level toward the steady state. These results were consistent with previous findings in the literature. All numerical experiments carried out here demonstrate the merits of the numerical MCS scheme. • Steady and unsteady flows in prismatic channels are simulated using MCS scheme. • Validation is done using MacDonald's analytical steady solutions for various flows. • The MCS scheme is extended so that it can be used to handle non-prismatic channels. [ABSTRACT FROM AUTHOR]

Pressure and water level control are quite challenging in grate-fired boilers due to higher combustion lag. Fluctuation in the pressure and the water level is more evident in the coal-fired grate boilers due to the presence of lower volatile and higher char. This results in suboptimal operation and poor performance of the boiler. This paper presents a novel predictive and dynamic simulation model for the drum dynamics analysis of a grate-fired boiler by combining a data-driven model and a thermodynamic model. A data-driven methodology is employed for the estimation of combustion, heat transfers, and circulation performance of the boiler. A novel thermodynamic model is proposed for the boiler dynamics of a hybrid boiler. The proposed data-driven model has been integrated with the thermodynamic model to reduce the randomness and improve consistency. Pressure and water level errors are estimated by comparing the predicted value and experimental result and the multi-objective optimisation technique is employed for the minimisation of errors. The Stochastic Gradient Descent algorithm is proposed for its ability to quick learning and adaptation to variations in fuel and combustion characteristics. The model demonstrates good accuracy in predicting the combustion and boiler dynamics of a grate-fired boiler. The proposed model has good potential to be used for the reciprocating grate solid-fuel boiler control in fluctuating load conditions. • A model for the prediction of boiler pressure and water level for grate combustion. • Integration of a data driven combustion model and the boiler dynamics model. • Multi-objective optimisation to minimise the errors in pressure and water level. • Stochastic gradient descent method to adapt with the change in fuel and combustion. • Model can be used for the control of a grate boiler in fluctuating load condition. [ABSTRACT FROM AUTHOR]

With the frequent regional flood disasters in recent years, the study of automatic scheduling and control technology of pump gate clusters has become crucial in related academic circles. Here, an automatic flood control and scheduling model for pump and gate clusters of water conservancy projects is constructed by combining hormone regulation and particle swarm algorithm. The model can regulate the maximum discharge flow and maximum water level of reservoirs according to the actual situation in order to achieve flood prevention and consumption prevention. The model is validated using two reservoirs in city A as an example. The results show that the maximum discharge flow of the two reservoirs after the model treatment is 1,996.16 and 16,738.28 m³ /s, which reduces the incidence of flooding in city A. In addition, after the optimal flood control scheduling, the maximum water levels of the once-in-a-century flood and once-in-two-centuries flood in city A become 80.41 and 81.66 m, respectively, which are in the safe water level range. The study is of great significance for the reduction of flooding. [ABSTRACT FROM AUTHOR]

In recent years, advances in information communications technology have proven their role in reducing water losses in water distribution systems. The geographic information system is a specialized set of Information Communication and Technology, which provides effective methods in the management of the water sector, in particular, non-revenue water. The Palestinian national strategic plan reported that reducing the non-revenue water from 38% to 35% will increase the revenue by US$40 million within 10 y. Similarly, the water sector regulatory council estimates that the non-revenue water rate is 33%. Surprisingly, water utilities have yet to implement extensive water loss management. Approximately 95% of the urban population in Khan Younis is served by a municipal water supply network. A high level of non-revenue water was recorded in Khan Younis in 2012 (about 40%). Many actions have been implemented to reduce the non-revenue water to 30% by 2020. This study aimed to quantify the non-revenue water of each water distribution zone and to classify the non-revenue water loss for distribution zone 20 (DZ20) per house connection. It was concluded that the adaptation of geographic information system made it possible to classify the highest loss rate of non-revenue water between 3% and 5% for DZ23. However, the distribution zone DZ20 showed a very high level of water loss (58.78%). The filed investigations illustrate that the developed map accuracy was presented as 83% accurate, whilst a strong positive correlation was revealed between non-revenue water and the age of the water meter and the number of populations occupying the house connection. [ABSTRACT FROM AUTHOR]

Harvesting of stormwater in the Gaza Strip is very important for the aquifer recharge since the stormwater infiltration is considered the sole replenishing source which reimburses the severe groundwater abstraction and protects the aquifer from unrecoverable deterioration. Gaza Strip experienced stormwater infiltration basins several years ago using different infiltration techniques. Waqf Basin is an existing stormwater infiltration basin located in Gaza City that used a surface natural infiltration technique, however, recently the basin was upgraded and augmented by drilling 18 boreholes (drywells) at zone 4 (western part of the basin). As a result, the basin has an improved infiltration capacity as revealed during the 2021–2022 wet season through field observation readings of water levels with a borehole infiltration capacity estimated as 111.0, 250, 316.7 m3 /d at 1.70, 3.40, 5.10 m ponded water depth, respectively. In addition, HYDRUS (2D/3D) software was used in this research to model/simulate Waqf Basin at ponded water depths 1.70, 3.40, and 5.10 m with the corresponding obtained borehole infiltration capacities as 289.0, 324.19, 250.39 m³ /d, respectively. The results emphasized that the single borehole infiltration capacity was in agreement with the field observed readings as the borehole infiltration capacity increases with the increase of basin ponded water depth. Nevertheless, the difference between HYDRUS and field observed results was attributed to the clogging effect which needs further studies in the future. Using the borehole infiltration technique is efficient when properly designed, implemented, and repaired at the end of each wet season to protect the system from permanent malfunctioning. [ABSTRACT FROM AUTHOR]

To study the vegetation community structure and diversity characteristics in the water-level fluctuation zone of Nanwan Reservoir, the water-level fluctuation zone of Nanwan Reservoir was divided into two water level elevations, one being 95-100 m and the other being 100--105 m. Subsequently, 3 typical plant communities of the water-level fluctuation zone of Nanwan Reservoir were selected for investigation. In the present study, a total of 34 species of plants were found. In listing the number of plants by family in order, the most abundant was Compositae, the second most abundant plant was Gramineae and the third most abundant was Legumes. In the present survey, Compositae accounted for 40.9% of the total number of species in the present survey, Gramineae accounted for 20.7% of the total number of species, and legumes accounted for 19.8% of the total number of species. According to the important values, the dominant species of different water level elevations in the descending zone of Nanwan Reservoir were sequenced. In the low water level elevation region, the first dominant species was Hemarthria altissima, the second dominant species was Erigeron canadensis, and the third dominant species was Kummerowia striata. However, in the high water level elevation region, the first dominant species was Kummerowia striata, the second dominant species was Hemarthria altissima, and the third dominant species was Carex neurocarpa. At the same time, in the low water level elevation region, a total of 19 species of plants were found. Among the 19 species of plants, annual herbs had the highest proportion at 47.37%, and there were 9 kinds of annual herbs. In the high water level elevation region, a total of 28 species of plants were found. In the 28 species of plants, perennial herbs had the highest proportion at 53.57%, and there were 15 kinds of perennial herbs. As the elevation of the water level rose, the diversity index, the evenness index and the richness index all increased, while the dominance index decreased. In conclusion, there was variation in the water level elevation in the water-level fluctuation zone of Nanwan Reservoir. An observation can be made that the different intensity of flood disturbance caused by the elevation change in the waterlevel fluctuation zone of Nanwan Reservoir is a significant factor in the structure and diversity of plant communities. [ABSTRACT FROM AUTHOR]

• The highest concentration of antibiotics was detected at the late aquaculture stage. • The concentration of antibiotics in natural water was related to aquaculture stages. • Antibiotics in coastal seawater mainly came from aquaculture ponds. • Correlation between antibiotics and water quality parameters was discovered. • The ecological risk caused by antibiotics increased with the aquaculture stages. The pollution of antibiotics commonly existed throughout the entire aquaculture process, but the residues of antibiotics at different aquaculture stages have rarely been studied. This study investigated the occurrence, distribution and risk assessment of antibiotics at different aquaculture stages (the non-aquaculture stage, the early aquaculture stage, the middle aquaculture stage, and the late aquaculture stage) in two typical marine aquaculture areas (Mahegang River and Dingzi Bay) surrounding the Yellow Sea. Fluoroquinolones and tetracyclines were commonly used antibiotics in the aquaculture of these areas with high detection frequencies (17% to 83%). Compared among four aquaculture stages, the highest concentration of antibiotics (9032.08 ng/L) in aquaculture ponds was detected at the late aquaculture stage. And the antibiotic pollution level of natural water was directly related to the aquaculture stages. Similarly, at the aquaculture stages, the detection frequency of antibiotics in sediments was higher than that at the non-aquaculture stage. Based on the correlation analysis, the concentration of main antibiotics in water showed a positive correlation with total nitrogen (p <0.05) and chlorophyll a (p <0.01), while it showed a negative correlation with salinity (p <0.01) in coastal water of the Dingzi Bay. According to the risk assessment, with the development of aquaculture stages, the selection pressure of fluoroquinolones and tetracyclines on resistant bacteria had increased. And the ecological risks caused by sulfonamides and tetracyclines to aquatic organisms had also increased markedly. Overall, this study may provide a reference for formulating regulatory policies regarding antibiotic use at different aquaculture stages. [Display omitted] [ABSTRACT FROM AUTHOR]

Water-level regulation can have significant impacts on coastal wetland ecosystems. In this study we sought to update marsh-bird-based ecological performance indicators (PIs) that support adaptive management of long-term outflow regulation for Lake Ontario. Previous PIs established in the mid-2000 s were based on single species and monitoring them required data not currently being collected at broad scales. We therefore focused on developing and validating community-level PIs using data from an ongoing, long-term, basin-wide monitoring program, the Coastal Wetland Monitoring Program (CWMP). After identifying species with documented responses to variation in water levels in the literature, we considered a suite of potential PIs by first examining correlations with both annual mean water levels and measures of interannual water-level fluctuations. We then used a mixed-modelling framework to determine which highly correlated PIs exhibited statistically significant relationships with water-level variables. Having established significant effects of water levels on the candidate PIs, we performed a power-sensitivity analysis to determine the degree of change in each PI that can be detected based on current CWMP sampling. From these analyses, we propose six potential marsh-bird based PIs: sum total abundance of sensitive marsh-obligate species, richness of sensitive marsh-obligate species, and abundance of each of red-winged blackbird (Agelaius phoeniceus), marsh wren (Cistothorus palustris), common gallinule (Gallinula galeata), and least bittern (Ixobrychus exilis). Of these, the community-based PIs of sum total abundance and richness of sensitive species appear most suitable for assessing the marsh-bird community response to outflow regulation on Lake Ontario. [ABSTRACT FROM AUTHOR]

Wetlands are amongst the world's most effective natural carbon sinks, and also have the potential to emit large quantities of stored carbon back into the atmosphere if disturbed. In the Murray-Darling Basin, high consumptive demand for water has led to widespread wetland loss and degradation. Remaining wetlands are commonly under additional pressure from grazing and trampling by feral herbivores or livestock and unseasonal flooding in summer to meet peak irrigation demand. Here, during a summer flood in Barmah National Park, we compared soil carbon and nitrogen and carbon emissions within, and outside of, a feral herbivore exclusion plot. The sustained global warming potential from the whole wetland (i.e., both within- and outside of the exclusion plot), totalled from both carbon dioxide (CO 2) and methane (CH 4) emissions, averaged 132.27 ± 9.88 g CO 2 -e m−2 d−1, an estimated 28- to 89-fold higher than the global average for natural wetlands. The high warming potential of the wetland was driven strongly by CH 4 emissions, which made up over 90% of total CO 2 -equivalents, with CO 2 contributing <10%. We expect these values represent peak CH 4 emissions from the site due to high water and soil temperatures, and low water levels, at the time of sampling. Soil carbon and nitrogen did not differ significantly within and outside of the exclusion plot, but surface soil samples indicated recent condition improvement in the absence of feral herbivores. We suggest that an emissions avoidance incentive could be developed around unseasonal, summer watering of forested floodplains where flood timing can be controlled. [ABSTRACT FROM AUTHOR]

This study employs the Weather Research and Forecasting Model (WRF) to simulate the wind field and pressure field in the designated study region. The ADCIRC (Advanced Circulation Model.) mode simulates the astronomical tide and storm surge in the Bohai Bay. During wave modeling, the impact of both wind field forcing and water level on waves in the Bohai Bay is simultaneously considered. A high degree of concordance is observed between the simulated outcomes and the collected data. Based on this, we employed numerical hindcast to acquire wind field, water level, and wave data for the study area over a 30-year period, from 1993 to 2022. An analysis is conducted on the joint distribution of wave height, period, and water level. A mixed probability model is then developed, and the environmental contour is generated to estimate design parameters for offshore floating photovoltaic. • 30 years of continuous wave and water level data are hindcast by numerical simulation. • The impact of both wind field forcing and water level on nearshore waves is considered. • A mixed model is proposed to describe the joint distribution of environmental variables. • The environmental contour is constructed to estimate design parameters for floating PV. [ABSTRACT FROM AUTHOR]

Water shortage and soil degradation are major challenges to agricultural production encountered in the semi-arid areas. The advantage of application of organic and biofertilizers in improving the soil productivity have been verified. However, there is still a lack of related research evaluating the effect of integrated fertilization measures on soil quality and crop productivity as well as their potential relationships under varying water supply levels. Herein, a two-year field study with two water levels (sufficient water, 220 mm; limited water, 60 mm) and five fertilization treatments (CK, no fertilizer; CF, chemical fertilizer; CFB, bio-fertilizer combined with CF; CFO, organic fertilizer combined with 70 % CF; CFOB, bio-fertilizer combined with CFO) was conducted to evaluate the effects on grain yield, resource use efficiency and soil quality. The results showed that the limited water supply decreased the grain yield, dry matter weight, nitrogen (N) uptake, N use efficiency, water productivity and most soil properties compared with those under sufficient water supply. Among different fertilization measures, CFOB was superior to other treatments both at sufficient and limited water supply, as it significantly improved the maize average yield (2022 and 2023), dry matter weight, N uptake, NUE and WP by 18.2–27.3 %, 9.2–31.2 %, 13.3–16.6 %, 38.9–62.3 %, 18.7–26.8 % compared with CF, respectively. Moreover, CFOB promoted the soil quality index (SQI) by improving the soil properties and consequently increased the grain yield. Accordingly, the integrated application of biofertilizer, organic and chemical fertilizer would be a sustainable fertilization strategy for improving soil quality and crop productivity, particularly in the semiarid sandy areas. Additionally, the results also revealed the underlying mechanisms of positive response between grain yield and SQI under varying water supply levels, which mainly attributing to the different key soil factors related to the grain yield. This study provided theoretical guidance for fertilization measures under varying water supply to improve soil quality and sustainable development of agriculture. • Integrated fertilization increased maize yield and resource use efficiency. • Integrated fertilization promoted most soil indicators to improve soil quality. • The key soil factors related to yield were different under various water supply. • Integrated fertilization increased maize yield by improving soil quality. [ABSTRACT FROM AUTHOR]

The use of dendrometers to measure the stem diameter (SD) of trees provides information about their actual water stress levels. The Scholander chamber is currently the gold standard for measuring stem water potential and thus for quantifying the water status of trees, despite being a laborious method, especially for apple trees. The aim of this study was to analyze dendrometer data to assess the water stress in drip-irrigated 'Gala' apple trees (Malus x domestica Borkh). A trial was performed in Grens, Switzerland, during the 2022 season. Three different irrigation treatments were applied (T1 = 100 % soil moisture-based irrigation, T2 = 30 % less than T1, and T3 = without irrigation). The irrigation treatments notably affected fruit production. Trees in T3 exhibited a significant yield loss of 26 %, whereas treatment T2 yielded 13 % less than the reference treatment T1. Although daily changes in the SD correlated with vapor pressure deficit (VPD) (r2 = 0.84), limiting the amount of water available to the plant disrupted this correlation (r2 = 0.27), with stem water potentials dropping by −1.7 MPa and a noticeable shift in stem movement (shrinking/expanding). Finally, we developed a suitable linear regression model that compared the shift in slope and offset of regression lines fitted for SD and VPD during initial non-stressed conditions (reference) with those under stressed conditions in order to estimate stem water potential. By integrating dendrometer parameters with VPD, the model effectively predicted stem water potential values. These findings suggest that dendrometers are effective indicators of water stress in apple trees. Further refinement of the model in field conditions could enhance the use of these sensors for irrigation management, providing more precise guidance on the timing and amount of water applied. • Dendrometer sensors are suitable water stress indicators for apple trees. • A linear model of TWD, VPD, and shift 'd' effectively reflects Ψstem values. • Dendrometers and climate data may replace labor-intensive Scholander measurements. • Dendrometers' simplicity and low cost make them ideal for automated irrigation systems. [ABSTRACT FROM AUTHOR]

Compound channels play critical roles in flood control, ecology, and aesthetics. Vegetation on the floodplains can further resist flood intrusion. However, less studies have been conducted to investigate the flooding in compound channels with vegetation on floodplains. In this paper, numerical simulations using FLUENT software are carried out to investigate the flood propagation pattern in the presence of vegetation on the floodplain for different water depth ratios. Comparison with the situation without vegetation reveals that the vegetation on the floodplain reduces the flow velocity on the floodplain, which further decreases the flow velocity in the main channel. This in turn causes the water level to rise. However, the effect on wave velocity and wavefront position is weakened when the initial water depth downstream is large. The water level rise is not significant when the floodplain is initially dry due to the shallow water depth on the floodplain after the overflow. Flow velocity near the vicinity of vegetation increases due to the vegetation induced streamline compression induced by the plant and forms an inverted triangular high flow zone. The presence of vegetation accelerates the stabilization of the lateral flow and reduces the lateral momentum and mass transfers. When the floodplain is initially dry, the total mass and momentum transfers are both reduced by about 60% within 3 s after the water flow reaches the section at the front of the vegetation. The vegetation can also make the lateral momentum and mass transfers firstly tend to be stabilized and then close to zero. The turbulent kinetic energy on the floodplain is greater than that without vegetation when the flow first enters the vegetated section and then decreases significantly after flowing through about 2 m vegetated zone, while the decrease is not significant when there is no vegetation. This study reveals that vegetation effectively mitigates flood propagation by enhancing flow resistance. The presence of vegetation prolongs the time required for the flood wave front to reach a specific area, thereby providing critical additional time for both evacuation and emergency response for affected residents. It is expected that this study could provide an in-depth understanding and improved knowledge on assessing the influence of floodplain vegetation on the flood propagation in compound channels, thereby providing reference for river design and flood control planning. • This study analyzes flooding in a vegetated compound channel. • It highlights vegetation's role in flood mitigation. • Vegetation accelerates recovery of lateral momentum and mass transport. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new fast-responsive oligothiophene-derivatized fluorescent sensor TTB was developed for monitoring Hg2+. • Sensor TTB for Hg2+ detection with high-sensitivity, high specificity, and quick response. • Sensor TTB coated test paper/cotton bud were used for convenient, reliable and quick visualization detection of Hg2+. • Sensor TTB was applied to accurately and sensitively detect Hg2+ in soil/urine/seafood/water/tea samples. • Sensor TTB was utilized to sensitively detecting and imaging of Hg2+ in living plants. Considering the high toxicity of Hg2+ to living organisms, accurately and sensitively detecting Hg2+ in environments, biology and food systems is of the utmost importance. Herein, we present a new fast-responsive oligothiophene-derivatized fluorescent sensor TTB for Hg2+ detection in real water/soil/urine/food samples. Sensor TTB shows a quick response, ultrahigh specificity, strong anti-disturbance, high-sensitivity with a satisfactory detection limit of 0.23 µM and good reversibility towards Hg2+. The response mechanism was well examined through Job's plot, FTIR spectra and DFT calculations. To examine naked-eye recognition of Hg2+, a visualization method by the TTB -coated test paper and cotton swabs was used for quickly detecting Hg2+. Additionally, sensor TTB shows good application flexibility and proves the capability for quantitative and accurate monitoring of Hg2+ levels in various water, soil, human urine, tea and seafood samples with an excellent efficiency. Moreover, fluorescence imaging experiments demonstrated that the TTB showed good cell-permeability and was utilized to detect/image Hg2+ in living plants. This study provides a powerful tool for accurately and reliably detecting Hg2+ in bio/environmental and food systems. [ABSTRACT FROM AUTHOR]