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The elevations of water surfaces hold important information on the earth's oceans and land surface waters. Ocean sea surface height is related to the internal change of the ocean's density and mass associated with ocean circulation and its response to climate change. The flow rates of rivers and volume changes of lakes are crucial to freshwater supplies and the hazards of floods and drought resulting from extreme weather and climate events. The Surface Water and Ocean Topography (SWOT) Mission is a new satellite using advanced radar technology to make headway in observing the variability of the elevation of water surfaces globally, providing fundamentally new information previously not available to the study of earth's waters. Here, we provide the first results of SWOT over oceans, rivers, and lakes. We demonstrate the potential of the mission to address science questions in oceanography and hydrology. Plain Language Summary: Earth is a water planet. The vast amount of ocean water has stored most of the heat released to the atmosphere since the Industrial Revolution through burning fossil fuels. Climate change is thus moderated by the ocean. Over land the freshwater in lakes, rivers, and reservoirs, a critical natural resource, is affected by the warming climate and direct human modifications. Processes of oceanic uptake of heat and carbon from the atmosphere and cycling of freshwater on land take place at spatial scales too small to have been adequately quantified from space. A new satellite, the Surface Water and Ocean Topography (SWOT) mission, was launched in December 2022. Using advanced radar technology, SWOT provides unprecedented global observations for understanding the ocean's role in climate change and how freshwater resources respond to human influence. SWOT observations near coasts will also advance understanding of how rising sea levels impact those coasts. Key Points: The first space observations of submesoscale ocean surface topography for understanding ocean's role in heat uptake from the atmosphereThe first space observations of the change of water storage of lakes and flow rates of rivers for understanding the freshwater cycleThe first space observations of the details of the change of coastal water levels to assess the impact of local sea level rise [ABSTRACT FROM AUTHOR]

Industrial and environmental granular flows commonly exhibit a phenomenon known as “granular segregation,” in which grains separate according to physical characteristics (size, shape, density), interfering with industrial applications (cement mixing, medicine, and food production) and fundamentally altering the behavior of geophysical flows (landslides, debris flows, pyroclastic flows, riverbeds). While size-induced segregation has been well studied, the role of grain shape has not. Here we conduct numerical experiments to investigate how grain shape affects granular segregation in dry and wet flows. To isolate the former, we compare dry, bidisperse mixtures of spheres alone with mixtures of spheres and cubes in a rotating drum. Results show that while segregation level generally increases with particle size ratio, the presence of cubes decreases segregation levels compared to cases with only spheres. Further, we find differences in the segregation level depending on which shape makes up each size class, reflecting differences in mobility when smaller grains are cubic or spherical. We find similar dynamics in simulations of a shear-driven coupled fluid-granular flow (e.g., a simulated riverbed), demonstrating that this phenomenon is not unique to rotating drums; however, in contrast to the dry system, we find that the segregation level increases in the presence of cubic grains, and fluid drag effects can qualitatively change segregation trends. Our findings demonstrate competing shape-induced segregation patterns in wet and dry flows that are independent from grain size controls, with implications for many industrial and geophysical processes. [ABSTRACT FROM AUTHOR]

The objective of this work is to contribute to the knowledge of the freshwater macroinvertebrate communities of Los Tuxtlas, Veracruz, Mexico. For this region, there is only limited knowledge of its aquatic crustaceans and mollusks. A total of 13,399 freshwater macroinvertebrates were collected from four river sections in each of the three sub-basins of the region using the Surber network in four seasons of an annual cycle (2021–2022) and were preserved in 70° alcohol. Organisms belonging to seven phyla, nine (sub)classes, 21 (sub)orders and 65 families were identified. The most abundant orders were Ephemeroptera (42.03%), with greatest abundance of the family Baetidae, and the orders Trichoptera (19.11%), Diptera (15.43%), and Coleoptera (3.98%). Four families exceeded 10% relative abundance, and together they total 61.02%: Baetidae (23.84%), Hydroptilidae (13.58%), Leptohyphidae (13.03%), Chironomidae (10.57%), and Elmidae (3.23%). The order Plecoptera was recorded for the first time in Los Tuxtlas, with three families. The orders Hydrachnidae and Ostracoda, as well as six families of the order Ephemeroptera, with only one previously recorded family, and six more families of the order Diptera, were also documented. Two species of invasive aquatic mollusks were found in several rivers and basins. In this work, a high diversity of freshwater macroinvertebrates occurred compared to other sites studied in Veracruz and Mexico, and new records of these taxa are provided for the region of Los Tuxtlas. [ABSTRACT FROM AUTHOR]

In times of rapid environmental changes, baseline biodiversity data are crucial for management. In freshwaters, fish inventories are commonly based on the capture and morphological identification of specimens. The sampling of environmental DNA (eDNA) provides an alternative to assess diversity across large catchments. Here, we used extensive historic data of fish communities collected across 89 river sites in all major catchments of Switzerland and compared their diversity and community composition to a single campaign of eDNA and electrofishing, respectively. Locally, we found that eDNA provided diversity estimates similar to the integrated historic richness, while the electrofishing campaign captured a significantly lower local richness. Fish species locally recorded by electrofishing were nested (Jaccard's dissimilarity index) within the respective eDNA community for most sites. Finally, eDNA sequence reads positively correlated with the overall electrofishing biomass. Despite the congruences, the eDNA data did not correlate well with the electrofishing water quality index. Overall, eDNA was more accurately assessing overall diversity than a simultaneous electrofishing campaign, but yet cannot be directly used to calculate fish-based water quality indices. [ABSTRACT FROM AUTHOR]

American Eel (Anguilla rostrata) population characteristics and distribution remain drastically understudied in the Caribbean region. We conducted the first island‐wide study to evaluate the distribution of density, length, and sex in relation to distance from the mouth of 23 stream reaches in five rivers in Puerto Rico. We found 287 American Eel at a mean density of 156.7 fish/ha. Sex ratios favored females (52:3) but most of the eel sampled were undifferentiated or undetermined. Generalized linear modeling indicated that upstream habitats with low eel density were optimal environments for production of large and female eel. Our findings indicate that Puerto Rico could significantly contribute to the spawning population and strengthen knowledge of American Eel in the Caribbean. Our findings could be used to guide local and range‐wide conservation efforts to ensure stream connectivity and access to optimal upstream habitat for survival of the population. [ABSTRACT FROM AUTHOR]

This article analyzed the infection characteristics of metacercariae of Metagonimus spp. (MsMc) in fish from 9 major water systems in Korea. A total of 19,568 fish in 87 species were examined over a period of 10 years (2011-2020). MsMc were detected in fish from all 44 survey areas in 9 water systems. Most of the surveyed sites showed very low and low infection levels (66.7%), while 33.3% of the areas, such as Tamjin-gang and Seomjin-gang, revealed moderate and high infection levels. High endemicity depends on the abundance of susceptible fish species, especially sweet smelt (Plecoglosus altivelis). The susceptibility index (SI) with MsMc in index fish, Zacco spp., was very low and low levels in 62.0%, moderate in 28.0%, and high in 10.0% regions. The SI was highest in the following order: Yeongam-cheon (283.8), Hoeng-cheon (192.3), Togyo-jeosuji (131.2), Deokcheon-gang (119.1), and Joyang-gang (106.3). The recent infection status of MsMc in P. altivelis was analyzed by the survey localities. In addition, except for P. altivelis, 9 fish species were highly infected with MsMc in some survey areas, including Zacco platypus, Z. koreanus, Z. temminckii, Opsariichthys uncirostris, Rhynchocypris oxycephalus, Carassius auratus, Acheilognathus rhombeus, Onchorhynchus masou, and Tribolodon hakonensis. In Korea, 74 fish species (15 families) are collectively listed as second intermediate hosts of Metagonimus spp. This review provides several novel characteristics of MsMc infection and clarifies the fish species of second intermediate host of Metagonimus spp. in this country. [ABSTRACT FROM AUTHOR]

This article explores how boat dwellers on the inland waterways of England and Wales - 'Boaters' - experience water and sanitation services. Boating populations are not counted as customers of private water utilities, so they exist within the 'dwelling paradox' and are positioned at greater risk of water and sanitation insecurity. Interviews and auto-ethnography document a myriad of ways in which participants use these resources on different vessels and waterways. The Capability Approach emerges as an apt framework for representing nuanced journeys from water and sanitation access to perceived quality of life. Findings suggest that equitable services can be defined as those which enable Boaters to live in ways they value. This entails reckoning with diverse - and potentially divergent - definitions of a 'good life', supported by the personal freedoms to achieve it. We argue this research makes a strong case for centring lived experiences in service design, particularly in instances of disagreement on the constitution of adequate service levels. Co-creating knowledge with people living in the dwelling paradox reveals complex relationships with authority and exclusion. We extend this theory, and the principles of equitable service delivery, to emphasise the situated desires, choices, and freedoms of the populations in question. [ABSTRACT FROM AUTHOR]

Fluvial ecosystems are essential for life on Earth. Despite this recognition and the growing implementation of restoration programs, measures aimed at halting riverine biodiversity's decline have had limited success, so far. The implementation of protected areas has been the cornerstone of terrestrial and marine conservation. However, this strategy has only been seldomly applied to the protection of fluvial ecosystems and there is still no clear evidence of its effectiveness. We reviewed existing literature in scientific journals and reports from conservation agencies and analysed existing protection policies dedicated to rivers as well as several case studies throughout the world. Our main aim is to understand the potential advantages and drawbacks of dedicated fluvial protected areas, comparing to terrestrial protected areas and even to the total absence of protection. We also delved in the process of implementing fluvial protected areas, namely in what concerns relevant spatial scales, conservation priorities, stakeholders' involvement and mitigation measures to potential threats. In total 173 references were retained after a comprehensive search on Google Scholar, SpringerLink, Scopus and ResearchGate. These studies revealed that, despite contradictory results, terrestrial protected areas provide some degree of protection to riverine ecosystems contained within their borders, namely through increased abundances and species richness of some specific groups. Comparatively, however, dedicated fluvial protected areas, designed to accommodate the uniqueness of these systems, hold a much higher potential. Yet, data regarding its effectiveness is still scarce, mainly due to the lack of general guidelines and resources to evaluate performance following establishment, which prevents stronger conclusions. [ABSTRACT FROM AUTHOR]

In contrast to fairly good knowledge of dissolved carbon and major elements in great Arctic rivers, seasonally resolved concentrations of many trace elements remain poorly characterized, hindering assessment of the current status and possible future changes in the hydrochemistry of the Eurasian Arctic. To fill this gap, here we present results for a broad suite of trace elements in the largest rivers of the Russian Arctic (Ob, Yenisey, Lena, and Kolyma). For context, we also present results for major elements that are more routinely measured in these rivers. Water samples for this study were collected during an international campaign called PARTNERS from 2004 through 2006. A comparison of element concentrations obtained for Arctic rivers in this study with average concentrations in the world's rivers shows that most elements in the Arctic rivers are similar to or significantly lower than the world average. The mineral content of the three greatest rivers (Ob, Yenisey, and Lena) varies within a narrow range (from 107 mg/L for Yenisey to 123 mg/L for Ob). The Kolyma's mineral content is significantly lower (52.4 mg/L). Fluxes of all major and trace elements were calculated using average concentrations and average water discharge for the 2004–2006 period. Based on these flux estimates, specific export (i.e., t/km2/y) for most of the elements was greatest for the Lena, followed by the Yenisey, Ob, and Kolyma in decreasing order. Element pairwise correlation analysis identified several distinct groups of elements depending on their sources and relative mobility in the river water. There was a negative correlation between Fe and DOC concentration in the Ob River, which could be linked to different sources of these components in this river. The annual yields of major and trace elements calculated for each river were generally consistent with values assessed for other mid-size and small rivers of the Eurasian subarctic. [ABSTRACT FROM AUTHOR]

Rivers serve as vital water sources, maintain ecological equilibrium, and enhance landscapes. However, the looming issue of floating debris stemming from improper waste disposal and illegal discharge, poses an imminent threat to river ecosystems and their aesthetic appeal. Conventional human-led inspections prove labor-intensive, inefficient, and prone to errors. This study introduces an innovative approach for river debris detection, employing Unmanned Aerial Vehicles (UAVs) imagery in conjunction with a refined YOLOv5n model. This approach offers three key contributions. Primarily, the YOLOv5n model is bolstered by integrating the Efficient Channel Attention (ECA) module and reshaping the MobileNetV3 backbone to align with MobileNetV3S, thereby significantly streamlining computational demands and model intricacy. Additionally, precision and speed are augmented by eliminating the detection head for larger targets, while decreasing computational requirements. Subsequently, to counter dataset scarcity, we curate a UAV-derived river debris dataset, encompassing five prevalent debris types, serving as an indispensable resource for method refinement and assessment. Lastly, the upgraded model's evaluation on Jetson Nano yields an mAP of 87.2%, merely 0.7% lower than the original YOLOv5n model. Remarkably, the refined model achieves substantial reductions of 57.1% in parameters, 52.6% in volume, and 54.8% in GFLOPs. Additionally, inference time is abbreviated to 57.3ms per Jetson Nano image, 13.4ms faster than the original. These findings underscore edge computing's potential in river restoration. In conclusion, the fusion of deep learning object detection and UAV imagery empowers adept river debris detection. [ABSTRACT FROM AUTHOR]

Although Pentecostalism is a major stream within Christianity in Sierra Leone, the first field where Protestant missionaries were active in tropical Africa, this ecclesial development remains marginally represented in research. The Pentecostalisation of Sierra Leone points to the nation's continuous recontextualization of Christianity from its inherited missionary vestiges to meet local cultural needs. In this paper, I discuss the retreat by Pentecostal clerics to nature (forests, rivers, and mountains) from where they expect to connect with the transcendent God and receive spiritual power. To do so, I first discuss Sierra Leone's traditional conceptualization of forests, rivers, and mountains as sites for the acquisition of spiritual power. Second, I briefly survey the emergence of Pentecostalism in Sierra Leone, probing the specific uses by Pentecostals of natural spaces. Finally, I conclude with an intercultural theological assessment of Sierra Leone's emerging Pentecostal uses and interpretations of natural spaces. [ABSTRACT FROM AUTHOR]

Biblical Hebrew has a rich vocabulary for clouds, rain, rivers, wadis, springs, wells, and cisterns, and this vocabulary indicates something of how ancient Israelites related to water. Water in all its forms was understood as a gift from God, especially when seasonal rain arrived according to expectation. Disruptions to the normal seasons were usually interpreted as a sign of judgment. By naming various forms of water and their divine origin, humans reveal their relationship with God and with water. [ABSTRACT FROM AUTHOR]

Rivers frequently delimit the geographic ranges of species in the Amazon Basin. These rivers also define the boundaries between genetic clusters within many species, yet river boundaries have been documented to break down in headwater regions where rivers are narrower. To explore the evolutionary implications of headwater contact zones in Amazonia, we examined genetic variation in the Blue-capped Manakin (Lepidothrix coronata), a species previously shown to contain several genetically and phenotypically distinct populations across the western Amazon Basin. We collected restriction site-associated DNA sequence data (RADcap) for 706 individuals and found that spatial patterns of genetic structure indicate several rivers, particularly the Amazon and Ucayali, are dispersal barriers for L. coronata. We also found evidence that genetic connectivity is elevated across several headwater regions, highlighting the importance of headwater gene flow for models of Amazonian diversification. The headwater region of the Ucayali River provided a notable exception to findings of headwater gene flow by harboring non-admixed populations of L. coronata on opposite sides of a < 1-km-wide river channel with a known dynamic history, suggesting that additional prezygotic barriers may be limiting gene flow in this region. [ABSTRACT FROM AUTHOR]

The development of low‐oxygen zones threatening marine life (hypoxia) occurs annually in multiple coastal regions of the world. The largest estuary of the continental United States, the Chesapeake Bay, typically has ≈10 km3 of water with dioxygen concentrations <3 mg L−1 in July. As numerical methods for refining model resolutions in targeted areas are becoming common, there is interest in assessing the feasibility of simulating coastal hazards such as hypoxia in Earth System Models (ESMs). These coupled models are typically not constrained by observations and thus likely to feature systematic biases in their land, atmosphere, or ocean components. This study relies on four numerical experiments to evaluate the sensitivity of Chesapeake Bay hypoxia to changes or biases in its external physical forcings. Hypoxia exhibits only a minor decrease (−1.6%) after reducing the Bay's terrestrial freshwater discharge by 9.5% (but keeping terrestrial nutrient loadings the same). Changes in freshwater discharges have their largest impact on hypoxia during one extreme event (−37% during 2011 tropical storm Lee). Similarly, changing oceanic conditions on the shelf or their temporal frequency impact hypoxia by only 5%–6%, indicating that the latter is predominantly dictated by local conditions. Although these results are promising from the perspective of ESMs, additional components of ESMs will need to be evaluated before general conclusions can be reached. We notably speculate that the Bay's hypoxia would exhibit higher sensitivity to other forcings not examined here, notably air temperatures and nutrient loadings. Plain Language Summary: Many coastal embayments of the world experience the development of "dead zones" during the summer, defined by very low concentrations of oxygen in water. The dead zones negatively affect the ecosystem including commercially‐important fisheries. Such a dead zone can be found every summer in the Chesapeake Bay, the largest and most productive estuary in the continental United States. Although these phenomena are typically the focus of local or regional managers, recent improvements in computer capabilities raise the possibility that dead zones could be successfully represented in the same type of computer simulators used for century‐long projections of the Earth's climate. Such simulators would provide a long term projection for the severity of dead zones throughout the world. The present study examines whether a realistic representation of the Chesapeake Bay dead zone can be obtained using information from these global computer simulations. The results show that the representation of the dead zone is not substantially different when using the global data sets selected for this study. This positive outcome opens the door for additional tests that should focus on other components of the global simulators, notably air temperatures and nutrients inputs from the land to the coastal embayments. Key Points: Chesapeake Bay hypoxia shows only a weak sensitivity to continental shelf conditions and variabilityChanges in shelf hydrography propagate throughout the Bay but surface temperatures are set by the meteorological forcingShort term hydrological events are not always captured well by global land models which can impact hypoxia substantially [ABSTRACT FROM AUTHOR]

Despite the distance between their different communities and the difficulties of medieval travel, the Jews of northern Europe developed typical common legal and communal traditions. Rabbinic students traveled hundreds of kilometers to study with famous rabbis, rabbis themselves often relocated from one community to another, and questions were regularly sent to faraway rabbinic authorities and were quickly answered. This article sheds light on the movement and communication patterns of medieval Jewish scholars as a social group. It includes three sections; the first focuses on the movement patterns of prominent rabbis, the second on their forms of communication, and the third on the way these practices were reflected in the organization of larger communal structures. Overall, the article highlights the major role that networks of movement and communication played in the intellectual culture of the rabbinic elite (and other Jews as well) in high medieval northern Europe. [ABSTRACT FROM AUTHOR]

Water treatment plant operators need to understand federal and state laws as well as the standards that apply to water treatment systems. They should also understand how drinking water regulations are administered and why compliance is essential to providing safe drinking water to the public. [ABSTRACT FROM AUTHOR]

This article presents the findings of a study on the water quality of the Tuirial River in Aizawl, Mizoram, North-East India. The study analyzed six parameters and found that all of them were within the standard range set by scientific agencies. However, the study also observed a decrease in water quality downstream, which may be attributed to human activities such as sewage discharge and agricultural runoff. The results highlight the importance of regular monitoring to maintain a healthy environment and the well-being of communities. [Extracted from the article]

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River bank-erosion, deposition and channel-shifting are considered most dynamic and significant geomorphological processes formed by complex geological, hydrological, and anthropogenic factors. In the present study, river Jiadhal is one of the main sub-tributary of the River Brahmaputra in the Dhemaji district of Assam that changes its channel course frequently due to bank-erosion and sediment- deposition in the intermediate part and lower course of the channel. A study on the changing course of the river Jiadhal was carried out using satellite imageries for the years 1987, 1997, 2007 and 2017. The study found that the changes in the river vary from time to time and the bank-erosion and sediment- deposition fluctuate from place to place. The total area of bank-erosion is 13.34 km2 from 1987 to 2017 and the total area of sediment-deposition is 14.59 km2 from 1987 to 2017. This paper evaluates how the shape, size and position of the Jiadhal River have changed from the years 1987 to 2017 using remote sensing and GIS techniques. The study is also necessary for effective management along the side of the river Jiadhal to control bank erosion and to mitigate the adverse impact of erosion and channel-shifting. [ABSTRACT FROM AUTHOR]

Silver carp (Hypophthalmichthys molitrix Valenciennes, 1844) have been invading North American rivers for decades, often altering zooplankton community structure and impacting native fishes. Silver carp invaded eastern South Dakota tributaries of the Missouri River in the early 2000s. Changes in dynamic rate functions can occur as invasive populations move to the latter stages of the invasion curve, but direct temporal assessments of silver carp populations are limited. Our objectives were to compare current growth of silver carp 1) between the Big Sioux and James rivers in South Dakota and 2) with previous growth recorded from the early stages of invasion (2009-2012) in these rivers. We collected silver carp in May and June of 2020-2022 using boat electrofishing and cast netting. We extracted lapilli otoliths for consensus aging from 99 and 82 silver carp from the Big Sioux and James rivers, respectively. We evaluated growth for each population using Bayesian von Bertalanffy models and compared posterior mean length at ages 2-5 to determine the probabilities of differences between rivers and with estimates from the introduction stage. Posterior estimated mean L8 values were similar between the Big Sioux (714 mm) and James rivers (709 mm); however, the probability that the posterior mean K estimate was greater for silver carp in the James River (0.271) than the Big Sioux River (0.248) was >99.9%. Estimated mean lengths at age 2 were larger in the Big Sioux and James samples than during the introduction stage, but mean lengths at ages 3-5 were smaller. Changes in growth characteristics indicate that growth has slowed in the current establishment stage of invasion from the earlier introduction stage. [ABSTRACT FROM AUTHOR]

Copyright of Escritos is the property of Escritos 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.)

As an emerging contaminant, microplastics (MPs) have caused global environmental pollution and become the focus of current research. This research presents a comprehensive literature review on the occurrence and distribution characteristics of MPs in surface water within China. The findings demonstrate that stainless steel barrels currently serve as the predominant tool for water sampling, whereas Fourier Transform Infrared spectrometer and Raman spectrometer are extensively employed for the detection of MPs. The mean abundance of MPs in rivers ranges from 0.57 to 930.00 n/L, while in lakes and reservoirs, it varies between 1.30 and 27.50 n/L. The size of MPs in surface waters is mainly less than 1 mm, with the transparent or white fibrous forms being the most frequently observed morphology, and polypropylene and polyethylene emerge as the primary polymer types. Additionally, the investigation of MPs in lakes and reservoirs in Northeast China and South China remains unexplored. Currently, an increasing number of Chinese cities are opting for surface water as their water source, so more studies should focus on enhancing the accumulation of research data on MPs in surface water to provide substantial support for the development of pollution control measures in the future. [ABSTRACT FROM AUTHOR]

Debris upstream of the bridge pier and through the flow variations, changes scour hole and river morphology. Dune forms downstream of the pier as a result of sediment movement in the pier scour phenomenon. The present study investigates the dune characteristics and geometrical parameters in experimental models. Experimental models are categorized into four cases including the pier, pier with buried debris, pier with free debris, and pier with free debris which was protected by bed sill at four various distances from the pier downstream face. It was concluded that debris submergence, densimetric particle Froude number, flow intensity, and bed sill affect dune geometrical parameters such as dune height (hd), dune crest position (xd), and dune length (ld). Results show dune height increases with debris accumulation up to almost 150% and its crest distance from the pier reduces up to approximately 100%. Also, in higher Fd, the dune height and its crest distance reduce with bed sill up to 50%, and in lower Fd, hd, and xd increase by up to 80% by using bed sill. Based on these effective parameters, three separate equations were proposed for hd, xd, and ld in pier scour with debris accumulation protected by bed sill. [ABSTRACT FROM AUTHOR]

Microplastics can contaminate water owing to their small size. If aquatic biota consume microplastics, they disrupt their reproductive processes, digestive tracts, and development. This study aimed to identify microplastic waste from silkworms (Tubifex spp.) in the Brantas River. The study was conducted in a descriptive manner by collecting samples of microplastic waste from silkworms and examining the shape, type, amount, and percentage of microplastic abundance in the river. An FTIR test was used to determine the microplastic content. Using a Zeiss Axio Zoom.V16 at 50x magnification, microplastic particles from individual worms and worm samples were visually identified. Then, the 50% hot needle test was used to determine the composition of the plastic. A total of 263 microplastic particles were found in the worm samples. Silkworms (Tubifex spp.) in the Brantas River, Kediri City, were shown to contain four types of microplastics, namely fibers, filaments, fragments, and granules, which were dominated by filament particles with 49% filament content, 45% fiber, 5% fragments, and 1% granules. The microplastic polymers identified via FTIR were polyethylene and ethylene-polypropylene-diene copolymers. These microplastics can originate from plastic bags, used drinking bottles, rope fibers, and pieces of water hose, which are often found around the Brantas River. Silkworms found in the Brantas River contain microplastic waste from various pollution sources. [ABSTRACT FROM AUTHOR]

Pollution of the atmosphere, soil, and water resources in Ukraine resulting from the Russian-Ukrainian war is a problem that requires immediate resolution, as the ecocide's consequences on the environment will be long-lasting and have a global impact. The aim of the study was to analyse the impact of active military actions on the atmospheric air, water resources of Kharkiv and Kharkiv Region, and the soils of the Ivory Coast of Sviatoslav National Nature Park in Mykolaiv Region by assessing their eco-geochemical state. The study of the impact of fires on the soil properties of the Ivory Coast of Sviatoslav National Nature Park using potentiometric, luminescence-bituminological, and spectrofluorometric methods revealed that the content of polycyclic aromatic hydrocarbons (PAHs) is the highest in pyrogenic areas, where low molecular weight PAHs are predominant; high molecular weight PAHs are also present, indicating recent burning of the territory. It was found that the PAH content is lower at microelevations. The aspiration method was used to investigate the atmosphere. It was shown that the level of air pollution in Kharkiv is low at all observation points, with a level of less than 5 on the scale of the air pollution index. It was found that the largest number of exceedances in the water bodies of the Kharkiv Region was recorded for such pollutants as sulphates (recorded at 17 points), ammonium nitrogen (at 16 points), biochemical oxygen demand (at 14 points), and dissolved oxygen (at 11 points). In all the most polluted water bodies, the maximum permissible concentration exceedances were recorded for 4, 3, and 2 hydrochemical indicators. The study results can be used in practice by ecologists to develop and implement measures to improve the ecological condition of the eastern and southern regions of Ukraine [ABSTRACT FROM AUTHOR]

The development of vegetation in riverbeds is an important part of river engineering, and an in-depth understanding of its hydraulic influence is greatly needed. Our research focuses primarily on common reed (Phragmites australis) in riverbeds. To date, little is known about the hydraulic impact of the Phragmites australis reed and both field and laboratory data are still very scarce. Consequently, the main goal of our study was to evaluate the effect of vegetation zones on the spatial distribution of turbulence. Based on laboratory measurements of local instantaneous velocities, the values of the turbulence intensity (degree) Tu were determined, and its spatial distribution was illustrated. Analysis of the results showed that the relatively dense clusters of plants (reeds) act as "openwork deflectors" of the current and very clearly shape its spatial distribution. This can also be observed in the case of the distribution of the turbulence parameter Tu. For example, in the case of the development of riparian vegetation in the form of quasi-triangular communities of common reed (Phragmites australis) located alternately, there is a channelization of the flow, but also spatial changes in its character that occur. This work only presents results for preliminary hydraulic tests for Phragmites reed. These experiments should also be continued for other species of flexible riparian vegetation such as wicker. In the laboratory, the hydraulic influence of only triangle-shaped vegetation zones has been studied. Therefore, there is also a need for further hydraulic studies on vegetation zones of shapes other than triangular, e.g., rectangular, as well as vegetation zones with irregular shapes The authors see the need for such research and have already planned its continuation. Research on the interactions between vegetation and the structure of water flow in the riverbed is a very important aspect of contemporary trends in river environment management. Conscious, planned, and model-tested locating (or removing) of vegetation in a stream allows for shaping hydraulic and morphological conditions, thus controlling the processes of erosion, transport, and accumulation of debris. [ABSTRACT FROM AUTHOR]

The Dina prokletijaca was found in the samples that were obtained from the Bekhal stream for the current investigation. The samples were gathered throughout the course of nine months, from March to October 2021. The reduced number of papillae on the back of D. prokletijaca distinguishes it. It can be identified by its stock and short body, the dorsal side with two dark and wide longitudinal paramedian stripes, and the ovisacs are curled reaching the somite four beyond the females' genital pores and coiled throughout their entire length. [ABSTRACT FROM AUTHOR]

Background: Rivers are complex systems in which all kinds of chemical, biological, and physical processes take place and chang e under the influence of various factors and variables in terms of dimensions, shape, direction, and pattern. The changes that occur in the conditions of rivers have many effects on the river ecosystem. Carrying out any activity in rivers requires knowing the rules governing the river and predicting the river's reaction to it to avoid the related harmful consequences. It is usually difficult to understand the processes of rivers by measuring hydraulic parameters on a real scale. On the other hand, sediment transport modeling is also a very complex and difficult matter because the information that is used to predict bed changes is basically uncertain and the theories used are experimental and highly sensitive to a wide range of physical variables. The high costs of laboratory equipment and the limitation of using measuring devices are among the other reasons that limit the use of physical methods and lead experts to mathematical and numerical modeling to simulate the flow inside water channels. Continuous change is one of the governing principles of every river, and a change in flow conditions also causes change s and displacement in other geometric characteristics of the river. Because rivers are often moving in their alluvial beds, different types of bed forms have been formed in the river bed due to the shear stress in the bed. The formed shapes cause a part of the surface water flow in the river to enter the porous environment below it and return to the surface water flow after oxygenating and feeding benthic organisms. This type of currents that arise from the mixing of surface current and subsurface current in the porous environment under and around the river is called hyperic current. The surface, subsurface, and underground water system s and exchanges between them are in three levels: point, interval, and watershed. Fallen tree trunks are common structures in rivers. One of the factors in creating hyperic exchange is the presence of a pressure gradient at the border of surface flow and the porous medium. The pressure gradient is caused by various factors such as obstacles in the flow path or bed forms. Depending on the magnitude of these factors, they will affect the amount of exchange and the depth of the hyperic expansion. The first step in understanding the hyperic phenomenon and its application is to examine changes in the characteristics of this area, including the amount of current exchange, depth, and retention time. Therefore, the objectives of this research are to investigate the effect of natural obstacles created by tree trunks on hyperic characteristics and the effect of the arrangement of natural obstacles created by tree trunks on hyperic characteristics. Methods: The current field research was carried out in the Garambadesht River of Gorgan in the summer and winter of 2021 to investigate the effect of fallen tree trunks on the river path as a natural flow barrier in different tree trunk thicknesses (30, 60, and 90 cm). As one of the most important sources of drinking water for the city of Gorgan, the Garmabadesht River, originates from the slopes of Yazdaki Mountain at a point 27 km southeast of Gorgan and continues to flow northward. Then, it passes through the high and complex heights and enters the eastern plains of Gorgan. To carry out the present research, piezometers were installed in the upstream and downstream of the tree trunks and then evaluated using a numerical model in the Comsol software environment, compared to the simulation of the hyperic flow to estimate the amount of exchange flow. Results: This study obtained convincing findings regarding the correlation between piezometer observational data and numerical simulation results. A 91% correlation was obtained between piezometer observation data and simulation results, which was used as a basis to investigate the computational exchange flows from the numerical model. The findings showed that the amount of exchanged flow in blocked conditions was higher than in non -blocked conditions. This issue shows that tree trunks can have a significant impact on the dynamics of hyperic flow, an important consequence of which is the direct impact on river ecosystems, especially in relation to the preservation of coastal vegetation and aquatic habitats. The investigation of the retention time of the flow lines in three obstacle states shows that the increase of the obstacle in the flow path has increase d the retention time because the flow lines have become deeper and their length has increased with the increase in the height of the obstacle, thereby increasing the retention time. Conclusion: The results indicate that the maximum amount of equilibrium discharge occurs in the case where the thickness of the tree trunk is 30 cm in winter. The amount of exchange flow with obstruction is higher than that without obstruction. The equilibrium flow rate in winter is higher than the exchange flow rate in summer. The investigation of the penetration of flow lines shows that the penetration rate of flow lines has increased with the increase in the thickness of the barrier. Considering the vastness of the research field, it is appropriate to conduct more research to discover more understanding of its mechanism. [ABSTRACT FROM AUTHOR]

Australian freshwater turtles are declining, reflecting global turtle trends. Understanding variation in turtle diets and habitat requirements can guide protection and restoration of ecosystems. Diet and niche overlap were investigated in three co‐existing species of turtle—the broad‐shelled turtle Chelodina expansa, the eastern long‐necked turtle C. longicollis and the Macquarie turtle Emydura macquarii, in three rivers in the Murray–Darling Basin, Australia, in relation to environmental variables.Dietary variation in relation to water quality (salinity) and macrophyte cover was investigated using stable isotope analyses (δ15N and δ13C) of turtle tissues (plasma, red blood cell, whole blood and nail) representing food assimilation over different antecedent periods. These stable isotope results were consistent with current dietary understanding based on stomach flushing, indicating that isotope analyses are a non‐invasive method for obtaining dietary information.There were temporal dietary differences, with strong shifts between spring and summer sampling periods, particularly in the blood plasma. Intraspecific variation in diets reflected in δ15N and δ13C related to body size. There was evidence of high dietary overlap among the three species, potentially creating competition, particularly when they co‐occur or resources might be limited.Continued degradation of turtle habitats and water quality affects turtle diet and reduces habitat availability, forcing the three species of turtle to co‐exist in diminishing refugia, increasing interspecific competition for food. Protecting and restoring freshwater ecosystems, including maintaining freshwater refugia, is essential to conserve already declining populations of the three Australian freshwater turtle species. [ABSTRACT FROM AUTHOR]