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The current investigation emphasizes the mathematical modeling of the hydrodynamics associated with the oscillating water column wave energy converter (OWC-WEC) device situated above undulating bottom of the ocean in the presence of ocean currents. The mathematical problem is investigated within the framework of the two-dimensional Cartesian coordinate system by incorporating the classical linear wave-structure theory. The boundary element method is used to address the corresponding boundary value problem. A significant attention is devoted to the analysis of the effectiveness and horizontal wave force exerted on the frontal barrier of the oscillating water column device by considering various values of incident wave and current parameters, as well as structural parameters related to both the oscillating water column device and the undulated seabed. Moreover, the study in the time domain is carried out in order to illustrate the variations in free surface elevations at different time instances by considering the influence of both following and opposing currents. The results demonstrate that the "Doppler Shift" effect of the frequency due to the presence of ocean currents significantly influences the resonating patterns of the efficiency and force curves. As the current velocities increase, the resonating frequencies occur for higher values of incident wavenumbers. [ABSTRACT FROM AUTHOR]

The article discusses an exhibition at the Middlesbrough Institute of Modern Art featuring the work of artist Jacqueline Poncelet. Poncelet's retrospective exhibition showcases her diverse practice over fifty years, highlighting her use of various mediums and themes such as jazz music, weaving, ceramics, and sculpture. The exhibition explores the continuity and evolution of Poncelet's work, emphasizing her unique approach to pattern-making and exploration of consciousness through art. The article provides insights into Poncelet's artistic journey and the influences that have shaped her creative process. [Extracted from the article]

Copyright of Tecnología y Ciencias del Agua is the property of Instituto Mexicano de Tecnologia del Agua (IMTA) 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.)

Underwater Wireless Sensors Networks (UWSNs) are deployed in remotely monitored environment such as water level monitoring, ocean current identification, oil detection, habitat monitoring and numerous military applications. Providing scalable and efficient routing is very challenging in UWSNs due to the harsh underwater environment. The biggest difficulties are the nodes inherent movement due to water current, long delay in data transmission, low bandwidth of the acoustic signal, high error rate and energy scarcity in battery powered nodes. Many routing protocols have been proposed to solve the aforementioned problems. There are three broad categories of routing protocols namely depth based, energy based and vector-based routing. Vector Based Forwarding protocols perform routing through virtual pipeline by defining their radius which give proper direction to packets communication. We proposed a routing protocol termed as Path-Oriented Energy Scaled Expanded Vector Based Forwarding (PESEVBF). PESEVBF takes into account all parameters; holding time, the source nodes packets routing path and void holes creation on the second hop; PESEVBF not only considers the packet upward advancement but also focus on density of the forwarded nodes in terms of number of potential forwarding and suppressed nodes for path selection. Node selection in resultant holding time is based on minimum Path Factor (PF) value. Moreover, the suppressed node will be selected for packet forwarding to avoid the void holes occurrences on the second hop. Performance of PESEVBF is compared with other routing protocols using matrices such as energy consumption, packet delivery ratio, packets dropping ratio and duplicate packets creation indicating considerable performance improvement. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia 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.)

Key Takeaways: After long‐term groundwater pumping increased subsidence‐related flood risk in Houston, the Texas legislature created subsidence districts to manage groundwater use. Reducing groundwater pumping requires alternative water supplies (AWSs) to meet current and future water demands. An assessment of AWS options in the Houston area determined that potential supplies should be more than ample to meet anticipated growth and demand. [ABSTRACT FROM AUTHOR]

Copyright of China Textile Leader is the property of China Textile Information Center 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.)

Crop development relies on water availability, needs, and application, necessitating large irrigation projects to ensure sustainable and equitable agriculture in the long term. This study investigates water losses and gaps during paddy cultivation in India's tropical semi-arid region, where agriculture is the primary economic driver for communities. Given the population's heavy reliance on rice, paddy cultivation was closely examined to identify irrigation-related vulnerabilities. An optimal irrigation plan was developed based on the analysis of the current water supply scenario for four different paddy production situations: 1) Rainfed (10 ha), 2) Rain + Canal irrigated (2174 ha), 3) Rain + Borewell + Rivulet irrigated (165 ha), and 4) Rain + Canal + Borewell irrigated (243 ha). The dependable water availability from rains and canals was calculated at a 75 % probability of exceedance to formulate an optimal water supply for the crop. Under this plan, the required water depth is reduced from 32.9 mm to 7.4 mm, saving 0.6167 Mm3 of water. In areas with optimized canal supply, no borewell water is needed for the canal-irrigated land supported by borewells (243 ha). [ABSTRACT FROM AUTHOR]

Globally, Indigenous Nations are disproportionately faced with water challenges. This is partly because current approaches to water governance continue to systematically exclude Indigenous peoples and their worldviews from contemporary water governance structures. Given the need to reform current water governance systems to redress injustices and secure water resources for Indigenous peoples, this paper presents the findings of a scoping review designed to identify the principles, values, challenges/problems, and existing models of Indigenous water governance around the globe. Findings indicate that "water is life" is a fundamental principle of Indigenous water governance frameworks, as is "water as an interconnected whole" that forms a greater part of a community's life and identity. The "Living Water, First Law" model and the Kistihtamahwin framework are examples of Indigenous water governance models identified. Colonization and the relegation of Indigenous knowledge remain a critical challenge to effective implementation of existing models of Indigenous water governance systems. This requires reform of contemporary water governance structures or formation of new systems that unsettle colonial legacies and privilege Indigenous worldviews and governance frameworks. These must focus on the overall health of the rivers, lakes, or freshwater entity and the holistic health of communities and be preceded by genuine nation-to-nation relationships. • Indigenous principles and values can (and should) underpin water governance and management. • Successful Indigenous water frameworks serve as indicators of sustainable water governance practices. • Colonization and relegation of Indigenous worldviews are a barrier to effective implementation of Indigenous strategies. • Privileging Indigenous worldviews/governance systems urgently required within nation-to-nation approach to water resources. [ABSTRACT FROM AUTHOR]

In August 2021, the blue button Porpita porpita , typically found in tropical and subtropical waters, was observed for the first time in the Yellow Sea. This study aimed to investigate the potential causes by analyzing the zooplankton community structure and the effects of water currents. The three stations, where P. porpita were recorded, were influenced by a warm and saline water tongue. The intruding current, which intensified during a La Niña event, also shaped the zooplankton community structure and distribution patterns. This research extends the known geographical distribution of P. porpita. The first observation of P. porpita in the Yellow Sea is likely attributable to the impacts of southeasterly winds and brought about by the intruding current, potentially suggesting ongoing region "tropicalization". Future studies will need to conduct a comprehensive analysis of additional surveys to better understand how the Yellow Sea pelagic ecosystem responds to climate change. • The known geographical distribution of Porpita porpita was extended. • The intruding current shaped the zooplankton community structure and distribution patterns. • Climate change may accelerate region "tropicalization" in the Yellow Sea. [ABSTRACT FROM AUTHOR]

Underwater wireless sensor networks possess considerable potential to monitor large and hostile underwater environments by reliably sensing, collecting, and forwarding data toward the surface sinks. Although the research community has made promising efforts, barriers such as continuous node mobility, longer delays, unavailability of location information, and energy limitations must be addressed. Taking this into account, this research aims to develop a hybrid and intelligent data collection scheme that considers node position and network characteristics during data forwarding. To accomplish the objective, the network is divided into two layers. The top layer, considered more dynamic, follows a hop-by-hop data forwarding scheme. The lower layer, experiencing stable water currents, follows a clustering-based data collection method. The proposed scheme, called Multilayer Dynamic Data Forwarding (MD2F), is suitable for large and deep underwater areas. MD2F is scalable as it uses a multi-sink architecture, while single or multiple autonomous underwater vehicles (AUVs) can be utilized depending on the area being monitored. Implementing hop-by-hop transmission and clustering-based data collection at different layers balances the network load, thereby increasing the network life. Results show that MD2F exhibits better performance when compared with Multilayer Cluster-based Energy Efficient (MLCEE) and Energy efficient and link reliable routing (E2LR) schemes, both are very close in working behavior. The results are encouraging in terms of delivery ratio, network throughput, and end-to-end delays. Alongside achieving these targets, the network also exhibits less energy consumption through load balancing. [ABSTRACT FROM AUTHOR]

Underwater wireless sensor networks (UWSNs) are used for the exploration of underwater resources, oceanographic data collection, flood or disaster prevention, tactical surveillance systems, and unmanned underwater vehicles. Underwater Wireless Sensor Networks offer innovative ways to investigate and anticipate how aquatic environments behave. Without position information, sensed data is useless in approximating target tracking or disaster avoidance. In this research, we propose the RLS (Reverse Localization Scheme), for short, a unique 3D centralized localization structure for MWSNs. The proposed approach enhances energy economy and condenses localization reaction time by an apposite level of accurateness in expressions of the motion exemplary of water currents, according to simulation findings. It reduces the number of message exchanges required for localization, average localization response time and saves vitality. Acoustic communications are the most used physical layer technology in underwater networks. Radio waves may only travel great distances over conductive salty water at extremely low frequencies (30-300 Hz), necessitating outsized antennae and significant transmission power. This RLS Enabled LoRa Networks architecture is built on an ad-hoc WiFi network. [ABSTRACT FROM AUTHOR]

The immense potential for ocean current energy harvesting is being actively explored as the push for renewable energy becomes more urgent. This paper demonstrates a tow testing platform built to examine and validate mathematical models related to the performance of tethered, underwater, hydrokinetic devices in development to harvest energy from ocean currents, and presents experimental results illustrating how such a system can be used. The platform has been modularly designed to allow for the testing of various tethered, underwater energygeneration systems, including kite-based systems, coaxial turbines, and duct sails. Previous research on tethered energy-generating systems has primarily been focused on airborne systems. Additionally, the limited experimental research on tethered, underwater energy-generation systems has relied on a rigid rod for mechanical and electrical connections between the test articles and instrumentation. The tow testing platform presented in this paper accomplishes the mechanical and electrical connection through a dual-function tether, featuring internal conductors and an external sheath to support towing loads. The goal of this platform was to enable the emulation of ocean currents, which are largely unidirectional, and to retrofit a regular pool into a cost-effective, adaptable, small-scale tow tank test bed. The capabilities of the system include two-way communication with tethered devices, multiple towing profiles in order to emulate different flow regimes, real-time control, and differential velocities via dual winch operation. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the prevalence of and factors associated with experimentation with and current use of water pipes and e-cigarettes among medical students. Methods: This was a cross-sectional multicentric study involving a convenience sample of students from medical schools in most Brazilian geographic regions. Information about experimentation with and current use of conventional cigarettes, water pipes, and e-cigarettes; beliefs and attitudes toward tobacco products; religiosity; and demographics were collected by means of an online structured questionnaire. We used descriptive statistics and logistic regression to analyze the association of those factors. Results: Our sample comprised 700 individuals from four Brazilian regions. Prevalence of experimentation with and current use of cigarettes, water pipes, and e-cigarettes were, respectively, 39.1% and 7.9%; 42.6% and 11.4%; and 13.1% and 2.3%. Water pipe experimentation was higher among those who had a sibling (adjusted OR = 2.64; 95% CI, 1.24-5.61) or friends (adjusted OR = 2.33; 95% CI, 1.63-3.31) who smoke. The same occurred regarding e-cigarette experimentation: siblings (adjusted OR = 2.76; 95% CI, 1.17-6.50) and friends (adjusted OR = 2.47; 95% CI, 1:45-4.22). Curiosity and scent/taste were the major reasons for water pipe use and e-cigarette experimentation. Although 93% of the responders learned about health damages of smoking during medical school classes, 51.4% reported having experimented with at least one of these tobacco products. Most responders who reported feeling the presence of God/the Holy Spirit in their lives were never experimenters of water pipes (59.2%) or e-cigarettes (55.3%). Conclusions: There is a high prevalence of experimentation with tobacco products among medical students whose siblings or friends smoke, despite their knowledge about smoking harms. [ABSTRACT FROM AUTHOR]

The National Oceanic and Atmospheric Administration (NOAA) National Ocean Service Center for Operational Oceanographic Products and Services (CO-OPS) manages the National Current Observation Program (NCOP) and Physical Oceanographic Real-Time Systems (PORTS®). These programs provide tide and current predictions, as well as real-time current and meteorological information. Outdated current predictions, navigational support requirements, and incident response scenarios (e.g., oil spills, vessel accidents) have highlighted CO-OPS' need for a rapidly deployable system that provides near-surface current and meteorological observations. To address this, CO-OPS designed, developed, and tested a realtime system based on a surface buoy platform, hereinafter referred as CURrents BuoY (CURBY). This paper provides an overview of the system design, field test results, operational applications, and future plans. In 2018, CO-OPS completed the build, integration, and testing of the first prototype CURBY. A successful field test was completed during 2018 in the Chesapeake Bay, and the first operational deployment followed shortly on the Delaware River in 2019. Resulting measurements were used to improve tidal current predictions and to plan for a 2021 regional survey. Initial success with tidal current survey operations led to design enhancement and wider use. During 2020-2021, CO-OPS partnered with the NOAA Office of Response and Restoration to build two new CURBYs to support emergency response applications in the Gulf of Mexico region. During 2022, two CURBY systems were deployed in the Columbia River, Oregon, to support additional NCOP operations. Future plans include establishing a long-term CURBY system for Kings Bay, Georgia, PORTS®. [ABSTRACT FROM AUTHOR]

The primary issue with the current water distribution network is the available head and necessary quantity of water. Designing a new or upgrading an existing WDN is needed to tackle such problems using software. Because of water shortages and pressure variations in Delhi, a small town in the city has been chosen to assess the current WDN using WATERGEMS V8i. This research aims to use WATERGEMS V8i to assess the existing WDN and make recommendations for the current WDN to meet current and imminent demand. The obtained results confirmed that pressures, flow rate and velocities in the pipes and junctions are insufficient to give enough water. The established water delivery network was then proposed to be modified to fulfil current and future demands. In any circumstances, a sufficient amount of water must be delivered to the user endpoint with sufficient head and volume. [ABSTRACT FROM AUTHOR]

The American Water Works Association (AWWA) was founded in 1881 by 22 water utility employees from various states. Its purpose was to exchange information about water-works management and advance both consumers and water companies. Over the years, AWWA has grown to over 50,000 members and has become the leading standards-writing organization for the water sector. It has also established local sections across the United States and Canada. AWWA has focused on research and addressing water challenges, and it has created the Water Research Foundation and Water For People. AWWA is led by a board of directors and has recently adopted its 2030 Strategic Plan. [Extracted from the article]

Copyright of Tecnología y Ciencias del Agua is the property of Instituto Mexicano de Tecnologia del Agua (IMTA) 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.)

Nanostructured GaN has many advantages in water splitting, such as stronger light absorption, shorter migration distance and more reactive sites. Here, we have introduced a conical nanostructured GaN with the significant improvement of water splitting performance. The fabrication method is simple without any extra mask, including electrochemical etching and ICP etching only, which largely reduces the complexity and cost for fabricating nanostructured GaN. By making use of the large number of pores formed in electrochemical etching, a conical GaN nanostructure can be prepared using ICP etching afterwards. Compared with the control planar GaN, the reflectivity of the conical GaN decreases by ∼2.57 times, indicating the light absorption of the conical GaN increases significantly. The corresponding water splitting current density of the conical GaN has also been measured, which is 0.69 mA cm−2 at 1 V, ∼6.27 times higher than that of control planar GaN (0.11 mA cm−2 ). Our work provides a simple method to fabricate high-performance nanostructured GaN, and broadens the application of III-nitrides for efficient energy storage and conversion. [ABSTRACT FROM AUTHOR]

Analysis of the velocity gradient of flocculators through Computational Fluid Dynamics (CFD) simulation can be essential to the optimization of hydraulic conditions in Water Treatment Plants. This study aims to simulate the velocity field in the last tank of a perforated tray-type flocculator and quantify locally velocity gradient (G) through CFD. This stage of flocculation has a higher risk of flocs rupture when there are not adequate conditions. Thus, simulations occurred at the flocculator current operational flow rate (7 l s-1 ), and at full capacity (9 l s-1 ). An alternative cost-effective and easy to implement modification was tested by increasing the number of orifices in the flocculator trays. As result, the velocity field indicates the formation of dead zones at the edges of the tank for all simulations, which facilitates short circuit occurrences. This is an indicator of reductions in water treatment efficiency. After structural modifications, simulations indicate a reduction in dead zone areas. Plus, as the flow rate increases, the maximum G inside the structure increases considerably (184 to 266 s-1 ), causing a risk for floc rupture. However, changing the number of orifices from 22 to 33 creates conditions for the flocculator to operate at higher flow rates without increasing the velocity gradient. [ABSTRACT FROM AUTHOR]

The UN summit entitled "Transforming Our World: Sustainable Development Plan 2030"considered the provision of clean water and sanitation (Goal no 6) one of the 17 key goals that the UN is striving to achieve. In this respect, Egypt is considered one of the countries that will suffer from water shortage because of establishing the Grand Ethiopian Renaissance Dam (GERD) and tremendous population growth. This research explores the current state of the water supply sector in Egypt based on the distinctive characteristics and challenges facing the development in this sector. Previous literature has examined the key performance indicators (KPIs) for the water supply sector, (PPPs) approach as an effective tool to promote the water supply sector, China's expertise in water supply by PPPsand summarizing the potential multiple risks associated with water supply projects from the literature reviews. Thereafter, an electronic questionnaire was conducted with multidisciplinary experts to identify optimal models (PPPs), weighted for (PPPs) pillars, and assess the potential risks by the Egyptian economy, and social circumstances in the field of water supply. As such, the findings in this research identify and rank the high potential risks based on the opinion of the experts, and an operating model to promote the (PPPs) projects in the water sector in Egypt was proposed based on the identified risk factors (KPIs) and the (PPPs) agreements. [ABSTRACT FROM AUTHOR]

• We combine GPN theory with a water stewardship approach. • Export-oriented fruit producers in South Africa face a range of water risks. • To ensure their water security, they deploy different mitigating strategies. • These strategies depoliticise post-apartheid water allocation in South Africa. • This has negative impacts for water governance & actors beyond the fruit industry. This paper investigates the strategies export-oriented agricultural firms use to mitigate water risks. By doing so, we respond to a gap in Global Production Network (GPN) scholarship, whereby the relationships between economic production and the natural environment have received insufficient attention. We build on GPN 2.0′s formulation of environmental risk as a causal driver of firms' strategies, combining it with the concept of water stewardship. Empirical evidence is drawn from the export-oriented fruit industry in South Africa's Western Cape. We find that while current water risk mitigating strategies are successful in securing water for fruit producers, these also have negative impacts on the wider South African water governance regime by depoliticising water allocation. In post-apartheid South Africa, this is deeply problematic. Our findings emphasise the imperative for research to consider the wider socio-political and ecological context when evaluating firm strategies to mitigate water and other environmental risks in South Africa and beyond. [ABSTRACT FROM AUTHOR]

Copyright of Revista Ambiente e Água is the property of Revista Ambiente e Agua 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.)

Marine mammals often aggregate and forage in specific 'hotspot' areas, which are associated with the predictability of prey sources driven by certain oceanographic processes. However, our understanding of the interactions between marine predators and the oceanographic processes remains incomplete, particularly in near-coastal and estuarine regions. This study investigated how predictable oceanographic processes influence the distribution patterns of Indo-Pacific humpback dolphins (Sousa chinensis) foraging in a known hotspot within the Pearl River Estuary, characterized by the complex topography of its manmade harbor and the interplay between strong tidal flows and river plumes. To address the fine-scale spatial distribution pattern of dolphin foraging, we conducted fixed passive acoustic monitoring of foraging 'buzzes' both inside and outside the harbor. Additionally, boat-based transect surveys were conducted to explore the relationship between dolphin foraging and associated water properties and current fields driven by oceanographic processes. Temporal trend analyses of buzzes revealed a pronounced tidal-related pattern in dolphin foraging activity, with increased detections during ebbing tides outside the harbor. Transect surveys indicated areas with elevated chlorophyll and turbidity levels attracted more dolphins during flood tides, whereas regions with high surface salinity gradients were preferred by dolphins during ebb tides. Oceanographic analysis recognized these bio-physical links as indicators of oceanographic features, including chlorophyll-rich river plumes, converging fronts, and shear-induced turbulence. These features enhance prey abundance and availability for humpback dolphins. This study highlights that oceanographic processes are crucial for determining the fine-scale spatiotemporal distribution of foraging in coastal dolphins, and offers insights into the effective prediction of dolphin aggregation. [Display omitted] [ABSTRACT FROM AUTHOR]

Copyright of Ciencia e Ingenieria Neogranadina is the property of Ciencia e Ingenieria Neogranadina 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.)

We aimed to explore the population dynamics of snail in 3 sites of the White Nile in Sudan. More specifically, we aimed to investigate the annual patterns of snail populations that act as intermediate hosts of schistosomes and monthly snail infection rates and ecological characteristics presumably related to snail populations. We collected snails for 1 year monthly at 3 different shore sites in the vicinity of El Shajara along the White Nile river in Khartoum State, Sudan. In addition, we measured air and water temperatures, water turbidities, vegetation coverages, and water depths and current speeds. Most of the collected snails were Biomphalaria pfeifferi and Bulinus truncatus. The population densities of snails and their infection rates varied across survey sites. The collected snails liberated S. mansoni and S. haematobium cercariae as well as Amphistome and Echinostome cercariae. Infected snails were found during March-June. The ecological characteristics found to be associated with the absence of snails population were: high turbidity, deep water, low vegetation coverage (near absence of vegetation), high water temperature, and high current speed. To our knowledge, this is the first longitudinal study of the snail population and ecological characteristics in the main basin of the White Nile river. [ABSTRACT FROM AUTHOR]

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL 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.)

Multi-year measurements of current velocity, salinity, and temperature from fixed and vessel-mounted sensors quantify Gulf Stream (GS) marine hydrokinetic energy (MHK) resource variability and inform development off Cape Hatteras, NC. Vessel transects across the GS demonstrate a jet-like velocity structure with speeds exceeding 2.5 m/s at the surface, persistent horizontal shear throughout the jet, and strongest vertical shears within the cyclonic shear zone. Persistent equatorward flow at the base of the GS associated with the Deep Western Boundary Current (DWBC) produces a local maximum in vertical shear where stratification is weak and is postulated to be a site of strong turbulent mixing. Repeated transects at the same location demonstrate that the velocity structure depends upon whether the GS abuts the shelf slope or is offshore. Currents from a fixed acoustic Doppler current profiler (ADCP) deployed on the shoreward side of the GS exceed 1 m/s 64% of the time 40 m below the surface. The 3.75-year time series of currents from the ADCP mooring document large, roughly weekly variations in downstream and cross-stream speed (-0.5 to 2.5 m/s) and shear (± 0.05 s-1) over the entire water column due to passage of GS meanders and frontal eddies. Current reversals from the mean GS direction occur several times a month, and longer period variations in GS offshore position can result in reduced currents for weeks at a time. Unresolved small-scale shear is postulated to contribute significantly to turbulent mixing. [ABSTRACT FROM AUTHOR]

This paper will explore the environmental problem surrounding microplastics pollution generated by the textile industry developing in the United States and globally. Microplastics are pieces of plastic so small they are best visible through use of a microscope with the pieces usually having a diameter of 5 millimeters or less. Plastic is used in numerous products today but the shedding of synthetic microplastics in textile materials have created unique and challenging problems because like all plastics they do not biodegrade naturally, and additionally are much easier ingested by wildlife as well as have the ability to easily absorb other toxins. For the most part current water regulations have not solved the problems and this paper will dive into the history of the various regulations surrounding the matter, as well as suggest proposals that countries need to consider adopting. [ABSTRACT FROM AUTHOR]

The paper presents results of experimental investigations of currents in the nearshore region of the south Baltic Sea. The analysis is based on the field data collected near Lubiatowo (Poland) using the measuring equipment which was simultaneously operated both by the Polish and Russian research teams. The venture was aimed at detection of rip currents that are rare and insufficiently explored phenomena in the south Baltic coastal zone. The data include wind velocity and direction, deep-water wave buoy records and currents surveyed by means of drifters. The measurements were carried out in the area whose hydrodynamics, lithodynamics and morphodynamics are typical of the south Baltic sandy coast. It appears that the nearshore water flows are mostly represented by longshore wavedriven currents with mean velocities of 0.22-0.53 m/s, and the maximum velocity of 1.32 m/s. Water circulation patterns resembling rip currents with velocities of up to 0.34 m/s were identified only on one day, when specific wave conditions occurred at the study site. Contrary to strong longshore currents generated by storm waves, rip currents occur under mild or moderate wave conditions, when many beach users are willing to swim in nearshore waters. The present findings can therefore be useful for the improvement of swimmers' safety in the south Baltic Sea regions. [ABSTRACT FROM AUTHOR]

In Alabama, Alligator Gar Atractosteus spatula populations have experienced a decline in abundance and due to their limited distribution are classified as a nongame species of moderate conservation concern. Conservation management plans have included creel limits and stocking to augment a diminished population within the lower Alabama River. Our objective was to evaluate gill‐net efficacy on catch and the environmental variables associated with improving broodfish capture rates for hatchery propagation. Broodfish collections were initiated and completed over 75 sample dates between March 2005 and April 2015. Collectors utilized multifilament gill nets consisting of three mesh sizes (101.6, 127.0, and 152.4 mm) and three net lengths (22.9, 30.5, and 61.0 m). Gill nets (n = 569) expended 2,173 h of soak time, resulting in the capture of 101 individuals (TL range = 1,020–2,210 mm). Catch was highest for the smallest mesh size, but net panel length did not influence catch rates. Median fish lengths increased with larger mesh sizes. Catch declined more than sevenfold for net soaks of 1 h or more, and the proportion of successful gill nets declined threefold for longer soak times. Examination of environmental conditions during and prior to the setting of gill nets demonstrated that fish capture success was in part influenced by various aspects of tidal current and water temperature. Catch success was 68% when nets were set at water temperatures of at least 20°C and when at least 50% of net soak time occurred during rising tides. However, success was lower when nets were set at temperatures less than 20°C, capturing Alligator Gar in 44% of all soaks and 37% for those on falling or slack tides. Agencies involved in hatchery propagation programs should continually evaluate field sampling methods, use of collection gear, and environmental conditions to increase broodfish catch rates and improve staff efficacy. [ABSTRACT FROM AUTHOR]

• A two-camera PIV/PTV technique measures falling of sediment particles in turbulent water. • Turbulent fluid motions are traced with neutrally buoyant seeding particles for PIV. • In-house made fluorescence-tagged particles enable effective PTV measurement. • The particle settling velocity is reduced by turbulence in most cases. • Fast tracking seems to increase the settling velocity at a certain case. Sediment transport is one key process in sedimentation problems. The dynamics of sediments in rivers will lead to an ecological change of the catchment. Among all complicated processes in sediment transport, the settling dynamics of solid particles in the water contribute to the water quality and geomorphology of a river channel directly. This paper aims at an investigation of the interaction between particle movement and water flow, with application to hydro-environment situations such as transport of fine sand sediment in natural streams. The Stokes number in this type of application is much smaller than unity at which enhancement of particle settling velocity by strong ambient turbulence has been observed in many numerical and laboratory studies. The present laboratory study is conducted to study the settling of sub-millimeter sized heavy particles in water with a relatively weak grid-generated turbulence. The two-phase flow is measured with the whole-field imaging techniques of particle image velocimetry (PIV) and particle tracking velocimetry (PTV). A two-camera PIV/PTV technique is used to obtain the instantaneous settling velocities of the solid particles and the turbulent water velocity field. Phase separation is based on an effective optical distinction of the two light scattering signals with fluorescent tagging on the solid particles. With this technique, it is found that in most cases of grid-generated turbulence the settling velocity of the heavy particles is slightly lower than the still water value. The falling heavy particles are also found to cause additional turbulence in the water with low ambient turbulence intensities. At one particular case of grid turbulence, the particles are found to fall with a depth-averaged settling velocity evidently higher than the still water value. The instantaneous turbulent fluid motions and particle trajectories tend to support the fast tracking effect to be related to the higher particle falling velocities. [ABSTRACT FROM AUTHOR]

Model evaluation is a crucial process in model development and quantified model evaluation metrics play a pivotal role in model calibration and validation. However, in current water quality and ecosystem models, conventional model evaluation metrics are derived from hydrological models and often overlook the non-normal distribution of water quality and ecological state variables. In this study, we proposed a series of metrics that consider non-normal distributions by modifying components of the Kling-Gupta efficiency. Subsequently, we tested the existing metrics and newly proposed metrics using four different synthetic datasets and the actual simulation case of total phosphorus, chlorophyll a , and dissolved oxygen concentrations. The results demonstrate that the newly proposed metric, Fu-Zhang efficiency, which replaces the ratio of standard deviations with the ratio of interquartile ranges to measure dispersion similarity, is more suitable for evaluating simulation results with lots of outliers in the measurements. Our study reveals the hidden perils in conventional integrated model evaluation metrics of water quality and ecosystem models and calls for the development of comprehensive and feasible quantitative evaluation frameworks to drive the next paradigm shift. • A review of existing model evaluation metrics in water quality and ecosystem models. • The conventional metrics are inapplicable for non-normally distributed measurements. • A new metric, FZE, is designed to evaluate non-normally distributed measurements. • The quantitative evaluation frameworks may drive the next paradigm shift. [ABSTRACT FROM AUTHOR]

This study employed a three-dimensional hydrodynamic model (COHERENS) to investigate the seasonal cycles of the mesoscale currents and eddies in the Persian Gulf with a 2-min horizontal resolution. The barotropic time step of 20 s and the baroclinic time step of 600 s were selected. In a vertical coordinate system with a vertical sigma array, there are equal numbers of vertical columns of water at each depth of the water volume. In this case, we considered 10 vertical sigma layers. We obtained a climatic stability during a 10-year run of the model. The simulation showed a coastal jet stream with a speed rate of 30 cm/s from May to October. The coastal jet stream in the vicinity of the Iranian coast is limited only to the surface as it flows southeastward and the counter current flows with a northwestern direction. However, this jet stream appears over the column of the water from the surface to the seafloor and flows southeastward along the Arabian coasts. Simulation results showed three cyclonic eddies with a diameter of about 100 km in September, the maximum speeds of which are observed at their north part. Decomposed eddies filled the entire water column. Additionally, at the end of summer when the eddy was well developed, the maximum vorticity was observed. The results revealed that anticyclonic eddy depths were higher than the depths of the cyclonic type, which is related to the extent of the eddy's development into the seabed and the effects of baroclinic instability on the water column. [ABSTRACT FROM AUTHOR]

Water current flow characteristics represent crucial information required for the management of coastal tourism destinations. Strong currents or strange flow patterns can pose risks to beach visitors. This research examined the currents at Pattaya Bay, one of the most famous beaches in the world. Numerical simulations were undertaken. Sophisticated simulation techniques were applied so that the calibrated simulation results were reliable. A whirlpool at the southern part of the bay was discovered, occurring every day during flood tides. The vortex rotated clockwise, with a magnitude between 0.34 and 0.41 m/s, and its radius could sometimes reach 500 m. The swirl was a natural phenomenon since it was created by the oblique orientation of the southern headland. The whirlpool was not deadly since its strength was normal for open coastal waters. However, care should not be neglected. This research raised awareness about the whirlpool's existence, so that proper management can be exercised. • Water current pattern in Pattaya Bay, Thailand, was investigated. • A whirl pool was discovered in Pattaya Bay. • The vortex happened naturally during flood tides. • The whirlpool in Pattaya Bay was not dangerous because its strength was mild. • Measures should be prepared and exercised continuously. [ABSTRACT FROM AUTHOR]

Nanoplastics (NPs) spread widely with water and air current, and they can accumulate in aquatic organisms, even penetrating biofilms, which may cause persistent toxicity and potential hazards. This current study aimed to reveal the toxicological mechanism of different functionalized polystyrene (PS) NPs on Daphnia magna (D. magna) by investigating toxicity endpoints in individual level and biochemical level. In this study, acute toxicity, behavioral parameters and biomarker responses of D. magna was measured in the exposure of different functionalized PS NPs (plain PS, PS-p-NH 2 , PS-n-NH 2 and PS-COOH). The results indicated that when exposed to the plain PS, ROS induction would activate MAPKs, thereby causing lethality and adverse behavior effects on D. magna ; while the functionalized PS NPs were less toxic than the plain PS, especially for PS-p-NH 2 which was severely flocculated after exposure, thus showing no immobilization at the investigated concentrations. Also, the antioxidant system was mainly stimulated due to the direct interaction with the cell surface receptor, which was different from the plain PS. Consequently, this work suggests significant effects of functional groups on NPs for environmental toxicity studies, and provides a better understanding of the toxicological mechanism on the toxicity of PS NPs toward D. magna. Image 1 • Acute toxicity, behavioral parameters and biomarker responses were analyzed for D. magna. • The acute and behavioral toxicity were functional-group-dependent. • A biochemical mechanistic insight into the toxicity of PS NPs was suggested. [ABSTRACT FROM AUTHOR]

The Yangtze River, which is the largest in Euro-Asian, receives tremendous anthropogenic nitrogen input and is typically characterized by severe eutrophication and hypoxia. Two major processes, denitrification and anaerobic ammonium oxidation (anammox), play vital roles for removing nitrogen global in nitrogen cycling. In the current study, sediment samples were collected from both latitudinal and longitudinal transects along the coastal Yangtze River and the East China Sea (ECS). We investigated community composition and distributions of nos Z gene-encoded denitrifiers by high throughput sequencing, and also quantified the relative abundances of both denitrifying and anammox bacteria by q-PCR analysis. Denitrifying communities showed distinct spatial distribution patterns that were impacted by physical (water current and river runoffs) and chemical (nutrient availability and organic content) processes. Both denitrifying and anammox bacteria contributed to the nitrogen removal in Yangtze Estuary and the adjacent ECS, and these two processes shifted from coastal to open ocean with reverse trends: the abundance of nos Z gene decreased from coastal to open ocean while anammox exhibited an increasing trend based on quantifications of hzs B and 16S rRNA genes. Further correspondence correlation analysis revealed that salinity and nutrients were the main factors in structuring composition and distribution of denitrifying and anammox bacteria. This study improved our understanding of dynamic processes in nitrogen removal from estuarine to open ocean. We hypothesize that denitrification is the major nitrogen removal pathway in estuaries, but in open oceans, low nutrient and organic matter concentrations restrict denitrification, thus increasing the importance of anammox as a nitrogen removal process. Image 1 • Both denitrifying and anammox bacteria contributed to the nitrogen removal in Yangtze Estuary and the adjacent ECS. • The abundance of nos Z gene decreased from coastal to open ocean. • The abundance of anammox bacteria increased from coastal to open ocean. • The distinct spatial distribution pattern of denitrifying bacteria was observed along environmental gradients. • The distribution patterns were impacted by both physical and chemical processes. [ABSTRACT FROM AUTHOR]

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The environmental condition has changed after the implementation of the '97' water diversion scheme, and there are still queries regarding the rationality of the water diversion scheme due to the potential difficulty of completing the releasing goal of Zhengyixia section. This paper simulated the implementation of the scheme through a simulation model for water resources allocation in the Heihe River. Then, the rationality of the water diversion scheme was evaluated. Results indicated that, in the current water demand situation, the releasing indicator could not be completed. The releasing indicator could be accomplished under two returning farmland schemes in the midstream, but the irrigation guarantee rate is low and the groundwater is overused. Therefore, there are some irrationalities between the '97' water diversion scheme based on economic, social and hydrologic conditions in the Heihe River in the mid-1980s and the current situation of the Heihe River Basin. [ABSTRACT FROM AUTHOR]

The considerable potential for rainwater harvesting (RWH) opens the door for the study of economic viability and risk indicators in this kind of system. The aim of this paper was to present economic and risk analyses of three RWH systems intended for water supply to single-family residences. The systems were analyzed based on water demand, degree of treatment and distribution arrangement. Economic, sensitivity and risk analyses were performed. The system with the basic treatment of rainwater and distribution by pressure (BX Pressure) was the most economically viable. The Net Present Value and the Intern Return Rate of the BX Pressure system was 480.36 USD and 6.85%, respectively. In the sensitivity analysis, both basic treatment systems were viable at any considered discount rate (0.00%–10.00%) and at a water price ranging from 1.58 USD to 2.72 USD for BX Pressure. In the risk analysis, BX Pressure was also the most viable system, presenting a risk probability of viability of 95.9% at current water prices. Water price, demand, lower discount rates and initial investment costs determined the greater economic viability and lower economic risk associated with domestic RWH systems. [ABSTRACT FROM AUTHOR]

The Dumbrăviţa Fishing Complex (Braşov, Romania) represents one of the most important Transylvanian stopovers for the black stork's (Ciconia nigra) fall passage. This study aims to prove the importance of adequate, species-synchronized drainage management of large ponds to maximize site potential as foraging area for black stork fall migrants, as well as to povide detailed recording of a new foraging pattern for this species. Throughout 4 consecutive fall passages (August-September; 2013-2016), black storks were monitored weekly, during evening foraging. Compared to bibliographical data (1995), the assessment of maximum numbers variation revealed a clear increase in numbers for the last 4 years, attributing highest values observed to passagesynchronized drainage of largest ponds. Pond focused analysis of fall passage peak numbers variation highlighted a positive impact of passage-timed water discharge on the occurrence of higher values for foraging groups. Regarding feeding ethology, foraging black storks were observed exclusively along the most vegetated shores, some groups displaying a new foraging pattern: repeated line feeding, deeper water dependent and potentially attributed to water currents. Foraging associations involved three Ardeidae species, with antagonistic behaviour only towards some Ardea cinerea individuals. Lastly, we propose the drainage of large ponds during the moments of maximum intensity for the black stork's fall passage. [ABSTRACT FROM AUTHOR]