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Various sources of pollution have been assigned as contributing to the Freshwater Salinization Syndrome (FSS), by which water bodies are undergoing concurrent salinization and alkalinization. In many urban areas that receive substantial snowfall, road salt application has been ascribed as the main source of chloride driving the FSS. In rural areas, however, inorganic (e.g. chemical) and organic (e.g. manure) fertilizer applications have been found to be the most important sources of chloride. Herein, we compared daily mean concentrations of chloride over the past decade of time between Coldwater Creek and Chickasaw Creek, two tributaries of Grand Lake St. Marys, the largest reservoir in Ohio. We also used Weighted Regressions on Time, Discharge, and Season (WRTDS) analyses to visualize trends in chloride data and compared chloride vs. nitrate levels to delineate likely sources of chloride for the two streams. We found that road salt application increased over time in both subwatersheds and that 37% and 25% of the chloride could be apportioned to road salt as a source in Coldwater Creek and Chickasaw Creek, respectively. Additionally, in Coldwater Creek, 37% of the chloride was apportioned to animal or septic sources, while 25% was apportioned to inorganic fertilizers, in comparison with 30% and 42% for Chickasaw Creek. Monitoring and assessing salinized streams for both chemical and biological water quality is important, particularly since the FSS has become increasingly linked to declines in water quality (e.g. harmful algal blooms, including recent upticks in Prymnesium parvum blooms) and is expected to be exacerbated with global climate change (e.g. increased precipitation causing increased runoff of chloride from the land). [ABSTRACT FROM AUTHOR]

Silver Carp (Hypophthalmichthys molitrix) populations have established and expanded throughout the lower Mississippi River basin (LMRB). Information pertaining to Silver Carp population mixing among rivers within the LMRB is lacking. Documented relations between Silver Carp otolith and river water barium (Ba) and strontium (Sr) microchemical signatures may enable estimation of origins of Silver Carp in the LMRB. Replicate water samples and otoliths from 308 Silver Carp were collected from the Cache, Arkansas, White, Yazoo, St. Francis, L'Anguille, and Mississippi rivers, and Merrisach Lake (situated along a canal connecting the lower reaches of the Arkansas and White rivers) within the LMRB. Water and carp otolith microchemical signatures exhibited consistent differences among water bodies. A classification and regression tree model exhibited 80% accuracy when assigning carp collected from the White, Arkansas, and Mississippi rivers based on fish-water microchemical signatures. Model accuracy decreased as smaller rivers were incorporated into models. Predicted natal origin based on otolith microchemical signatures suggested the White River (43%) and the lower Mississippi River (39%) were the likely origins for ~ 82% of the Silver Carp sampled. Despite the prevalence of adult Silver Carp within the Arkansas River system, fewer (18%) appeared to have originated there compared to the White and Mississippi rivers. Long-term water sampling and additional isotopic measurements may refine analyses to better determine the relative contributions of Silver Carp from the smaller river systems. Population mixing of Silver Carp among tributary rivers appears to be common within the LMRB, and removal efforts may benefit from evaluating the magnitude of fish movement and connectivity among rivers. [ABSTRACT FROM AUTHOR]

Urban rivers face sustained anthropogenic pressures limiting biodiversity. Yet, urban waterways such as the Detroit River are important habitat in supporting regional diversity. The Detroit River is a Great Lakes Area of Concern where conservation and restoration efforts prioritize improved biological and habitat integrity in the connecting channel. This study explores benthic macroinvertebrate in submerged aquatic vegetation across five mainstem channel wetlands and two tributary sites of the Canadian wetlands to describe spatial patterns and diversity. We first examine inter-wetland differences between five mainstem wetlands by hierarchical cluster analysis, NMDS and PERMANOVA, identifying two mainstem groups: one comprising of two middle reach wetlands (Detroit River Marshes and Grass Island), the second showed similarities among wetlands across all reaches (Turkey Creek, River Canard and Peche Island). The latter groupings shared similar habitat characteristics, deeper and finer grain-sizes, and functional feeding group characteristics - low abundances of shredders. Second objective, we perform an intra-wetland comparison for Turkey Creek and River Canard to analyze for differences along tributaries. At neither River Canard nor Turkey Creek we observed significant tributary influence on mainstem communities but had found the Turkey Creek tributary communities significantly differed from the channel communities. Diversity metrics and Hilsenhoff Biotic Index illustrate strained benthic communities across the river. We had also found water quality to be consistently moderately degraded. Our findings differ from prior analyses within emergent vegetation that indicate variable water quality conditions between mainstem and tributary and non-impaired macroinvertebrate communities. [ABSTRACT FROM AUTHOR]

The “T” vein is a tributary of The Great Saphenous Vein (GSV) located in the upper third of the leg with a perpendicular course to the GSV. It usually crosses the tibial bone and feeds by reflux of varicose veins of the lateral aspect of the leg. It is of surgical interest because it is involved with a significant percentage of varicose networks. The aim of this study is to analyze the prevalence of the T vein pattern in a cohort of patients affected by Chronic Venous Insufficiency (CVI), as well as its possible association with Venous Leg Ulcers (VLU) of the lateral aspect of the leg. One thousand nine hundred and twenty-two consecutive patients (1441 females and 481 males) were evaluated from January 2013 to May 2024 by means of clinical examination and the same Duplex Ultrasound Scanning (DUS) protocol. We assessed the frequency of patients presenting with the T vein pattern and the percentage of patients in which it causes symptomatic reflux. We also evaluated the susceptibility, respectively in the T vein and in the CVI cohort, of venous ulcerations (C5-C6 clinical classes according to the Clinical, Etiological, Anatomical, and Pathophysiological, CEAP, classification) in the medial and/or in the medial and lateral aspect of the leg vs exclusively in the lateral aspect of the leg. A p-value

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Model simulation plays a significant role in the water resources cycle, and the simulation accuracy of models is the key to predicting regional water resources. In this research, the Qianhe tributary at the Weihe River basin in Western China was selected as the study area. The tributary was divided into 29 sub-basins and 308 hydrological response units according to the spatial raster data and attribute data of the hydrology, meteorology, topography, land use, and soil types. On this basis, a soil and water assessment tool (SWAT) model for runoff simulation and evaluation of this region was established. A sensitivity test and parameter calibration were then executed on 15 parameters involved with surface runoff, soil flow, and shallow underground runoff. The simulation results demonstrate a calibration and verification error of 3.06–10.08%, with very small uncertainties throughout the simulation, whereas they exhibit relatively large errors in the simulation of the dry period (winter) but, in contrast, quite small errors in the rainy period (summer). In addition, the simulated runoff with a low value is overestimated. When the annual, monthly, and daily runoff are 4–13.5 m3/s, 4–69.8 m3/s, and 40–189.3 m3/s, respectively, the relative error is smaller, and the simulation results are more accurate. The sensitive parameters predominantly affecting the runoff simulation of the basin include soil evaporation compensation, runoff curve coefficient, vegetation transpiration compensation, and saturated hydraulic conductivity in this region. In the case of hypothetical land use change scenarios, we observe a great reduction in simulated runoff in arable land, woodland, and grassland, while we observe an increment in construction and residential land and wasteland. The annual and monthly runoff are increased by above 54.5%. With the increase in cultivated land and forestland, the annual and monthly runoff decrease by 24.6% and 6.8%, respectively. In the case of hypothetical scenarios under 24 climate combinations, if the precipitation remains unchanged, the increase and decrease in temperature by 1 °C leads to a decline and increment of runoff by −0.72% and 5.91%, respectively. With regard to the simulation for the future under the RCP2.6 and RCP8.5 climate scenarios, downscaling was employed to predict the runoff trend of the future. In short, this study provides a method for runoff inversion and water resources prediction in small mountainous watersheds lacking hydrological and meteorological observation stations. [ABSTRACT FROM AUTHOR]

In order to comprehensively analyze the surface water quality characteristics of the Liangxi River in Wuxi. This study monitored the changes in water quality in the Hongqiao and Liqiao sections of the Liangxi River from 2020 to 2022.Combined with the change of water quality in Meiliang Bay from 2021 to 2022 and the water quality of eight tributaries at the entrance of Taihu Lake of Liangxi River and the junction of the Beijing-Hangzhou Canal from September to December 2021.This study comprehensively explored the influence of water diversion in Meiliang Bay and the change of water quality in Liangxi River on the water quality of the main river section. The results showed that the surface water quality of the Liangxi River system has gradually improved, and its indexes of DO, COD, permanganate, ammonia nitrogen, and total phosphorus all meet the three kinds of surface water standards. High temperatures in summer will accelerate the aerobic process of the water system, cause the decrease of DO content, and further lead to the increase of COD, permanganate, ammonia nitrogen, and total phosphorus in the water system, which is one of the important factors affecting the water quality of Liangxi River. The contents of ammonia nitrogen and total phosphorus in Meiliang Bay are higher in summer. Combined with the Canoco 5 correlation analysis, it makes a great contribution to the content of ammonia nitrogen and total phosphorus in the Liangxi River. However, the content of COD in Sanjieqiaobang is higher, and the confluence of its branch water flow is one of the factors leading to the high content of organic pollutants in the Liangxi River.It is suggested that the water quality of Liangxi River should be comprehensively improved from three aspects: the stability of Liangxi River water quality in summer, the control of water diversion in Meiliang Bay, and the treatment of main river water quality. [ABSTRACT FROM AUTHOR]

After the reservoir is impounded, the increase of water depth changes the hydrodynamic conditions of the river channel, the backfilling of the incoming sediment from main stream to the tributaries resulted the sedimentation of tributary mouth, affecting the effective storage capacity of the reservoir and the safety of navigation. In this paper, taking Xiluodu Reservoir as an example, the characteristics of water and sediment transport in the main stream and tributaries was studied, and the formation mechanism of barrier sandbar at the tributary mouth was analyzed based on the measured data and the three- dimensional mathematical model. The results is indicated that: the deposited sediment of tributaries mainly comes from the upstream incoming sediment and the backfilling of the main stream sediment, and the upstream incoming sediment is the main source of the sedimentation of tributaries; the main stream backflows into tributaries near the tributary mouth, and a convective and circulation zone are formed, where the sediment is easy to be deposited. The slope of Xixi River and Niulan River is slow, and the risk of the barrier sandbar formation is large, while the slope of Meigu River is large, and the risk of the barrier sandbar formation is small; for Xixi River, Niulan River and Meigu River, the distance of main stream backfilling into the tributary increases with the increase of discharge, and the influence of water level on the distance of main stream backfilling into the tributary is not obvious when the Xiluodu Reservoir is operating at high water level. In Jinyang River and Xisujiao River, the distance of main flow backfilling into the tributary is basically unchanged with the increase of discharge, and the distance of main stream backfilling into the tributary increases with the increase of water level. The research results provide a basis for controlling the risk of barrier sandbar formation at the tributary mouth of reservoir under the new condition of water and sediment. [ABSTRACT FROM AUTHOR]

Copyright of Bylye Gody is the property of Cherkas Global University Press 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.)

The present investigation carries out a Systematic Review of the scientific Literature to analyze the purification methods of treatment of affluent with a high content of heavy metals that affects metallic structures, reported in the scientific literature. A total of 805 studies obtained from the Scopus, IEEE, Web of Science, Scielo, Elsevier, Springer databases were initially retrieved; with the Google Scholar, Semantic Scholar and IEEE Xplore search engines; Finally, 16 were included in this investigation. As a fundamental result, 12 methods of purification of affluent contaminated with heavy metals were identified. For the present investigation, the conventional treatment methods for developing countries were especially significant. The results obtained in several investigations indicate that metallic structures are affected when they are in contact with tributaries with a high content of heavy metals, mainly when the tributary is related to industrial waters. [ABSTRACT FROM AUTHOR]

Rivers networks represent hierarchical dendritic habitats within terrestrial landscapes and differences in connectivity and land use influence dispersal, and consequently biodiversity patterns. We, therefore, measured variation in water chemistry and fish abundance and related these to a number of landscape characteristics (e.g., wetland, urban, wooded, and agricultural) in the River Klarälven and its 30 permanently flowing tributaries. We hypothesized that these environmental attributes would differ between tributary and main stem habitat and that these differences would be driven by landscape attributes including land use. We found considerable intertributary variation in temperature and nutrient levels, and between the tributaries and the main stem. Generally, water temperature was lower in the tributaries, whereas nutrient levels were higher in the tributaries. The lower water temperature has implications for coldwater fishes, and we found two fishes, burbot and lamprey, associated with coldwater tributaries. We also found an inverse relationship between water quality and anthropogenic land use. Protecting tributaries with low anthropogenic impact will likely become increasingly important with ongoing global warming as they can function as thermal refugia for coldwater fishes. Hence, this study underscores the need to evaluate water courses at regional scales to identify spatial refuges and ensure connectivity. [ABSTRACT FROM AUTHOR]

Riverine habitat mosaics, including tributaries, are an important reason the Green River subbasin supports the largest remaining population of federally endangered Colorado Pikeminnow Ptychocheilus lucius in the Colorado River Basin. Upstream Colorado Pikeminnow distribution is limited by Flaming Gorge Dam and few typically occurred in the reach immediately downstream of the dam, which is the reach most affected by thermal and hydrologic alterations. However, fish captures and passive integrated transponder (PIT) antenna sampling of previously tagged individuals from 2011 to 2021 revealed seasonal congregations of up to 75 Colorado Pikeminnow annually in the mouth of Vermillion Creek, a small tributary in the regulated reach. Approximately 11% (N = 93 individuals) of the entire 2017–2018 Green River basin population were encountered in Vermillion Creek over the 11-y study, an underestimate of use considering that untagged fish were not detected by antennas. Colorado Pikeminnow used Vermillion Creek primarily when Green River spring flows from Flaming Gorge Dam were high and cold in May through mid-June when the confluence was a large, deep backwater warmer than the main channel and supported forage fishes. Intra-annual encounters revealed seasonal residence times for individual Colorado Pikeminnow up to 91 d, and multiple inter-annual encounters indicated site fidelity. Frequent detections of individual Colorado Pikeminnow in a Yampa River spawning area soon after their detections in Vermillion Creek indicate this tributary may be an important resource for reproductive adults. The intensive and basin-wide PIT tagging and detection program for Colorado Pikeminnow enhanced our understanding of the importance of small habitat nodes such as Vermillion Creek in the Green River drainage network. Understanding and protecting these seasonally available riverine habitat mosaics used for prespawning conditioning may assist with recovery of Colorado Pikeminnow. [ABSTRACT FROM AUTHOR]

The water and sediment characteristics of the Yellow River are related to the development of the river basin and have great significance in determining the future trends in sediment load. In this study, the water and sediment characteristics and influencing factors were analyzed. The correlations among hydrological and sediment parameters were further analyzed. The results showed that the annual average sediment concentration (AASC), the annual sediment load (ASL), the median grain size of sediment (MGSS) and the annual sediment transport modulus (ASTM) decreased. Therefore, the sediment control effect of the tributaries was significant. The annual runoff (AR) of the hydrological stations in the Yellow River increased from 2002 to 2019. Altogether, AASC and ASL of the Yellow River showed a downward trend. The sediment was reduced by water storage and sediment detention of reservoirs. AASC and ASL increased significantly due to water and sediment regulation tests and floods. However, the silt in the river channel could be washed with the help of current scouring and flood to slow down the silt. There was a strong correlation between AASC and ASL, whether the Yellow River or its tributaries. Besides, there was a significant impact of AASC and ASL of the tributaries on the sediment of the Yellow River, showing that the sediment control of the tributaries was essential. The sediment in the main tributaries and the Yellow River showed a decreasing trend from 2002 to 2019, which is conducive to the ecological harmony and stability of the Yellow River. [ABSTRACT FROM AUTHOR]

Natural rivers often have complex water network structures, and the continuous water inflow from tributaries may have crucial impacts on the water quality of ecological water replenishment in the mainstream. This study selected two main inflow rivers of the largest lake in Hebei Province (Baiyangdian), the Fu River and Baigou River, to explore the influence of tributaries on the quality changes of ecological replenishment water in the mainstreams. In December 2020 and 2021, water samples were collected along the two river routes, and eutrophic parameters and heavy metals were determined. The results showed that the tributaries of the Fu River were all severely polluted. With the inflows of the tributaries, the comprehensive pollution index of eutrophication greatly increased along the replenished water route of the Fu River, and the replenished water in the lower reaches of the Fu River mainstream was mostly considered moderate to heavy pollution. Whereas, because the Baigou River's tributaries were only moderately polluted, the water quality in the Baigou River's replenished water was mostly better than moderate pollution. Due to the slight pollution of heavy metals in the tributaries, the replenished water in both the Fu and Baigou Rivers did not show any impact from heavy metal pollution. Correlation and principal component analysis indicated that the main sources of serious eutrophic pollution in the tributaries of the Fu and Baigou Rivers were related to domestic sewage, industrial wastewater, plant decay, and sediment release. This non-point source pollution then caused the decline in the quality of the replenished water in the mainstreams. This study exposed a long-standing but neglected problem in ecological water replenishment and provided a scientific foundation for conducting better water management to improve the inland water environment. [ABSTRACT FROM AUTHOR]

Fluvial flows carrying high sediment loads may plunge into reservoirs to form turbidity currents. However, the effects of tributary inflows on reservoir turbidity currents have remained poorly understood to date. Here a 2D double layer-averaged model is used to investigate a series of laboratory-scale numerical cases. By probing into the hydro-sediment-morphodynamic processes, we find that tributary location and inflow conditions have distinct effects on the formation and propagation of reservoir turbidity currents, and lead to complicated flow dynamics and bed deformation at the confluence. Two flow exchange patterns are generated at the confluence: turbidity current intrusion from the main channel into the tributary; and highly concentrated, sediment-laden flow plunging from the tributary into the turbidity current in the main channel. Tributary sediment-laden inflow may cause the stable plunge point to migrate downstream and is conducive to propagation of the turbidity current, whilst the opposite holds in the case of clear-water inflow from the tributary. Tributary inflow leads to a lower sediment flushing efficiency as compared to its counterpart without a tributary. Yet a high sediment concentration in the tributary may reinforce turbidity current in the reservoir, thereby increasing sediment flushing efficiency. Around the confluence, the planar distributions of velocity and bed shear stress of the turbidity current resemble their counterparts in confluence flows carrying low sediment loads or clear water. Yet, the bed exhibits aggradation near the confluence due to the turbidity current, in contrast to pure scour in a river confluence with a low sediment load. Appropriate account of tributary effects is required in studies of reservoir turbidity currents, and for devising strategies for long-term maintenance of reservoir capacity. Article highlights: Tributary inflow may cause the stable plunge point of reservoir turbidity current to migrate either upstream or downstream and modify its propagation. Tributary inflow may lead to lower sediment flushing efficiency by reservoir turbidity current. Tributary discharge and sediment concentration may lead to disparate bed deformation at confluence. [ABSTRACT FROM AUTHOR]

Copyright of Roca: Revista Científico-Educacional de la Provincia de Granma is the property of Universidad de Granma, Departamento Editorial 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.)

Invasive Silver Carp (Hypophthalmichthys molitrix) have established populations throughout the Missouri River basin. The main-stem Missouri River has undergone a multitude of alterations, creating a channel with greater mean depths and velocities, limiting optimal habitat for Silver Carp. Tributaries to the Missouri River may provide refuge from the swift flows within the main-stem Missouri River and, therefore, may play a vital role in the life-cycle of Silver Carp throughout the basin. Understanding the spatial extent under which these invasive fish function in this large, open river system is crucial to inform management efforts. Here, we used otolith microchemistry of Silver Carp from the Kansas River, a major tributary to the Missouri River, to reconstruct environmental histories as a means to assess the proportions of resident (individuals who never left the Kansas River system) and transient (individuals who at some point occupied the Missouri River) individuals. Silver Carp within the Kansas River were predominantly residents (adults = 54%; juveniles = 65%) with the majority of reproduction coming from within the Kansas River itself. These results suggest removal efforts in the Kansas River may be effective means of managing this invasive fish species. Transient fish exhibited short durations of signatures indicative of the Missouri River (mean percent of data points for adults = 10% and juveniles = 36%), suggesting movements into the Missouri River were brief. These results highlight the importance of connectivity of tributary habitat among large rivers and provides important information for invasive species management. [ABSTRACT FROM AUTHOR]

Model simulation plays a significant role in the water resources cycle, and the simulation accuracy of models is the key to predicting regional water resources. In this research, the Qianhe tributary at the Weihe River basin in Western China was selected as the study area. The tributary was divided into 29 sub-basins and 308 hydrological response units according to the spatial raster data and attribute data of the hydrology, meteorology, topography, land use, and soil types. On this basis, a soil and water assessment tool (SWAT) model for runoff simulation and evaluation of this region was established. A sensitivity test and parameter calibration were then executed on 15 parameters involved with surface runoff, soil flow, and shallow underground runoff. The simulation results demonstrate a calibration and verification error of 3.06–10.08%, with very small uncertainties throughout the simulation, whereas they exhibit relatively large errors in the simulation of the dry period (winter) but, in contrast, quite small errors in the rainy period (summer). In addition, the simulated runoff with a low value is overestimated. When the annual, monthly, and daily runoff are 4–13.5 m3/s, 4–69.8 m3/s, and 40–189.3 m3/s, respectively, the relative error is smaller, and the simulation results are more accurate. The sensitive parameters predominantly affecting the runoff simulation of the basin include soil evaporation compensation, runoff curve coefficient, vegetation transpiration compensation, and saturated hydraulic conductivity in this region. In the case of hypothetical land use change scenarios, we observe a great reduction in simulated runoff in arable land, woodland, and grassland, while we observe an increment in construction and residential land and wasteland. The annual and monthly runoff are increased by above 54.5%. With the increase in cultivated land and forestland, the annual and monthly runoff decrease by 24.6% and 6.8%, respectively. In the case of hypothetical scenarios under 24 climate combinations, if the precipitation remains unchanged, the increase and decrease in temperature by 1 °C leads to a decline and increment of runoff by −0.72% and 5.91%, respectively. With regard to the simulation for the future under the RCP2.6 and RCP8.5 climate scenarios, downscaling was employed to predict the runoff trend of the future. In short, this study provides a method for runoff inversion and water resources prediction in small mountainous watersheds lacking hydrological and meteorological observation stations.

Copyright of Revista Didasc@lia: Didáctica y Educación is the property of Universitaria de Las Tunas, Centro de Estudios de Didactica 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.)

Five countries share the catchment of the Tisza River (Central Europe). In most households electricity and water are available, and by washing synthetic clothes they can produce a large number of microfibers. However, in many sub-catchments of the river, the wastewater treatment is insufficient; therefore, microplastics (MP), especially plastic microfiber emissions into rivers, represent a problem. Our goal was to analyze the suspended sediment and microfiber transport at the low stage, making repeated (2021 and 2022) measurements in the Tisza River (946 km) at 26 sites across three countries. Water sampling was performed by pumping 1 m3 of water through sieves (90–200 µm). The mean MP transport in 2021 was 19 ± 13.6 items/m3, but it increased by 17% in 2022 (22.4 ± 14.8 items/m3). The most polluted sections were the Upper Tisza (Ukraine, Hungary) and the Lower Tisza (Serbia), where wastewater treatment is not satisfactory, whereas the Middle Tisza (Hungary) was less polluted. The tributaries increased the sediment and MP budget of the main river. Microfibers dominate (84–97%) the suspended MP transport, and thus it can be determined that they originated from wastewater. The MP transport was influenced by the availability of wastewater treatment plants, dams, tributaries, and mobilization of bottom sediments. At the low stage, no connection was found between the suspended sediment and MP particle transport. [ABSTRACT FROM AUTHOR]

To fill the knowledge gap about the functioning of the lake–river system subjected to restoration treatments, two tributaries, a shallow, restored lake and its outflow, were examined. The quality of water inflows, lake and outflow was compared before (BR), during sustainable (SR, deep water aeration, phosphorus inactivation and biomanipulation for 3 years) and limited lake restoration (LR, only aeration for 2 years). Physico-chemical parameters were analysed monthly at five stations. The nutrient concentrations at the inflows decreased over the years due to the improvement of water and sewage management in the catchment (in Mielcuch from 18.0 to 8.0 mgN L−1 and 1.0 to 0.6 mgP L−1). The decline at the outflow was the result of a better quality of water at the tributaries and SR in the lake. During LR, decrease of phosphorus concentration still occurred (0.11 mgP L−1), but nitrogen concentration slightly increased (3.9 mgN L−1). Although the outflowing waters still transported a high content of chlorophyll a and suspended solids during SR, their amount was lower (34.5 μg L−1 and 17 mg L−1, respectively) than that during BR and LR. During restoration, it is significant to monitor the water quality not only in the lake but also at the outflow. The slow deterioration of water quality at the outflow indicated that introducing changes in the applied restoration methods must be done carefully because the previously achieved effect may be lost. Hence, restoration of the upstream lake and good quality of its tributaries are of great importance for water bodies located downstream. [ABSTRACT FROM AUTHOR]

Excessive phosphorus has become the primary reason for the deterioration of the water quality of the upper Yangtze River Basin. Here, we comprehensively study variations in total phosphorus (TP) concentration and TP loads in the upper reach of the Yangtze River during 2004–2017 (after the impoundment of the Three Gorges Dam). Non-point source TP loads flowing into the mainstream are also analyzed based on the base flow segmentation method. TP concentration in the mainstream showed a fluctuating trend of decreasing–increasing–decreasing from 2004 to 2017. TP loads from tributaries had a greater impact on TP concentration in the mainstream than the retention effect. Non-point source was an important source of TP loads. Average TP loads from non-point source pollution were 24.9 × 106 kg per year, contributing about 50.8% of the TP loads from 2004 to 2017. Non-point source TP loads were mainly from Jinsha River and Jialing River, accounting for 59.1% of total non-point TP loads, and they mainly occurred in the wet season. The long-term variation trend of TP loads from tributaries was affected by economic development, intensity of pollution control and significant discharge change. In terms of pollution control, we suggest comprehensive treatment of point and non-point source pollution. HIGHLIGHTS TP concentration of mainstream showed a trend of decreasing–increasing–decreasing.; TP loads from tributaries had a greater impact on TP concentration in the mainstream than the retention effect.; Average TP loads from non-point source pollution contributed about 50.8% of total TP loads.; Long-term variation trend of TP loads was affected by economic development, intensity of pollution control and significant discharge change.;

[Display omitted] • Landslide dams can change the shape of a river and upset its equilibrium state. • The transient geomorphic response after landslide-induced river damming is quantified. • Landslide dam leads to disturbances in the channel-hillslope system of the adjacent tributaries. • A database of 226 landslide dams in the study area is constructed. It is widely acknowledged that landslide-induced river damming plays a vital role in influencing landscape evolution as it drives river transience. However, how this transient state is transmitted and evolves is still being determined. Here, we focus on the Min and Dadu Rivers in the eastern margin of the Tibetan Plateau, an area abundant with paleolandslide dams, these dams have been used to quantify the transient geomorphic response after damming. We first identified 226 paleolandslide dams through remote sensing and field verification, and calculated the parameters of each paleolandslide dam. Second, we investigated the river longitudinal profile、channel steepness index (k sn) and knickpoints along the trunk of both rivers. Third, we extracted all sub-basins smaller than 1000 km2 from both rivers and calculated each sub-basins channel steepness index and hillslope morphology metrics (local relief and slope). The results show that: (1) The landslide dam aligns spatially with the elevated sections of the river's longitudinal profile and areas exhibiting high k sn values, and coincides with specific river knickpoints. (2) Approximately 61 % of the trunk dams show higher k sn values, local relief, and slope values in the surrounding sub-basins, accompanied by peak values. Places with these patterns in our study area sometimes had as many as six landslide-induced river damming events. (3) The 4 typical dams showed a trend of decreasing k sn and hillslope morphology in tributaries upstream and downstream of the dam, and the metric values of the sub-basin are negatively correlated with the distance from the trunk dam. Our findings highlight that the trunk landslide-induced river damming event leads to disturbances in the channel-hillslope system of the adjacent tributaries. Such an approach will provide the potential to examine the transmission of geomorphic responses to landslide-induced river damming and help us better understand the geomorphological evolution after river damming. [ABSTRACT FROM AUTHOR]

Lake Xingyun is a hypertrophic shallow lake on the Yunnan Plateau of China. Its water quality (WQ) has degraded severely during the past three decades with catchment development. To better understand the external nutrient loading impacts on WQ, we measured nutrient concentrations in the main tributaries during January 2010–April 2018 and modelled the monthly volume of all the tributaries for the same period. The results show annual inputs of total nitrogen (TN) had higher variability than total phosphorus (TP). The multi-year average load was 183.8 t/year for TN and 23.3 t/year for TP during 2010–2017. The average TN and TP loads for 2010–2017 were 36.6% higher and 63.8% lower, respectively, compared with observations in 1999. The seasonal patterns of TN and TP external loading showed some similarity, with the highest loading during the wet season and the lowest during the dry season. Loads in spring, summer, autumn, winter, and the wet season (May–October) accounted for 14.2%, 48.8%, 30.3%, 6.7%, and 84.9% of the annual TN load and 14.1%, 49.8%, 28.1%, 8%, and 84.0% of the annual TP load during 2010–2017. In-lake TN and TP concentrations followed a pattern similar to the external loading. The poor correlation between in-lake nutrient concentrations and tributary nutrient inputs at monthly and annual time scales suggests both external loading and internal loading were contributing to the lake eutrophication. Although effective lake restoration will require reducing nutrient losses from catchment agriculture, there may be a need to address a reduction of internal loads through sediment dredging or capping, geochemical engineering, or other effective measures. In addition, the method of producing monthly tributary inflows based on rainfall data in this paper might be useful for estimating runoff at other lakes. [ABSTRACT FROM AUTHOR]

Water chemistry can vary spatially and temporally within a riverscape (i.e., reservoir, rivers, and tributaries) due to different surficial geologies, groundwater influences, surrounding land use, habitat type (i.e., reservoir or river), and water residence time. Microelemental signatures may be absorbed by calcified structures of fish and have been used to describe their environmental history. The ability to identify this history depends in part on spatial distinction and temporal stability of those water signatures. The objective of this study was to compare trace concentrations of four elements in water collected at nine locations within the North Platte River (n = 4 sites), one tributary of the river (n = 1 site), and Lake McConaughy (n = 4 sites) in July 2017 and from April to September in 2018 to assess spatial distinction and temporal stability of these microelements. Inductively coupled plasma‐mass spectrometry was used to analyze concentrations of Ba:Ca, Mg:Ca, Mn:Ca, and Sr:Ca in each water sample. Spatial distinction and temporal stability of microelements were assessed using a Cochran‐Mantel‐Haenzel test. A Bonferroni correction was applied to account for multiple comparisons per element. No significant spatial distinction was detected among the nine individual sites (df = 3, p =.05–.72) and plots of elements displayed temporal variability at the tributary site and the North Platte River site below the tributary site. However, when individual sites were classified to habitat type (i.e., "river," "tributary," or "reservoir"), all four microelements were found to be spatially distinct (df = 3, p <.01). All elemental ratios except Mg:Ca were found to be temporally stable (df = 3, p =.02–.08). This study identified microelements that were spatially distinct between a river, tributary, and reservoir and temporally stable which will allow for accurate assessment of environmental history of fish using hard‐part microchemistry. [ABSTRACT FROM AUTHOR]

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

Interpretation of geomorphic features and drainage characteristics of Bhagirathi River sub-basin was carried out with the help of morphometric analysis. Various, areal, linear and relief parameters were calculated to assess drainage basin characteristics quantitatively, determine infiltration and surface runoff behavior control of drainage. The drainage network was analyzed using IRS-PAN satellite data and Survey of India toposheets. Findings show that the Bhagirathi sub-basin from Gaumukh to Chirbas exhibits dendritic to sub-dendritic drainage patterns and is characterized by third-order streams up to Chirbas. Stream segments development in the basin is controlled by local relief and slope. The bifurcation ratio indicate disparity of bifurcation between the different stream orders owing to structural control and circularity ratio indicates sub-elongated shape of basin. This study will be helpful for making soil erosion prevention strategies and its conservation and facilitate the understanding of water retention function in river basins.

Copyright of Brazilian Business Law Journal / Administração de Empresas em Revista is the property of Administracao de Empresas em Revista 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.)

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

Five countries share the catchment of the Tisza River (Central Europe). In most households electricity and water are available, and by washing synthetic clothes they can produce a large number of microfibers. However, in many sub-catchments of the river, the wastewater treatment is insufficient; therefore, microplastics (MP), especially plastic microfiber emissions into rivers, represent a problem. Our goal was to analyze the suspended sediment and microfiber transport at the low stage, making repeated (2021 and 2022) measurements in the Tisza River (946 km) at 26 sites across three countries. Water sampling was performed by pumping 1 m3 of water through sieves (90–200 µm). The mean MP transport in 2021 was 19 ± 13.6 items/m3, but it increased by 17% in 2022 (22.4 ± 14.8 items/m3). The most polluted sections were the Upper Tisza (Ukraine, Hungary) and the Lower Tisza (Serbia), where wastewater treatment is not satisfactory, whereas the Middle Tisza (Hungary) was less polluted. The tributaries increased the sediment and MP budget of the main river. Microfibers dominate (84–97%) the suspended MP transport, and thus it can be determined that they originated from wastewater. The MP transport was influenced by the availability of wastewater treatment plants, dams, tributaries, and mobilization of bottom sediments. At the low stage, no connection was found between the suspended sediment and MP particle transport.

In order to provide a theoretical basis for effective control of soil and water loss in the Yellow River basin, the paper analyzed the unoff and sediment changes and driving factors in the Hantaichuan basin in the Inner Mongolia section of the Yellow River and used the con fidence ellipse correlation analysis, cumulative anomaly, 5-year sliding average and double cumulative curve methods to analyze the water and sediment change process in the basin and the contribution rate of precipitation and human activities to the water-sediment change of Han taichuan basin. The results show that there is a significant inter-annual variation and a decreasing trend of runoff and sediment in the Hantai chuan basin and the inter-annual sediment transport is significantly correlated with the runoff. According the calculation, the average annu al runoff reduction in the Hantaichuan basin from 1998 to 2017 is 5.68 million m³ and the effect of runoff reduction is 43.73%, of which, rainfall plays 36.09% inhibitory effect and human activities play 136.09% promoting effect. From 1998 to 2017, the average annual sediment reduction is 2.22 million tons and the effect of sediment reduction is 80.73%, of which, rainfall plays 6.30% inhibitory role and human activ ities play 106.30% promoting role in the sediment load reduction. Human activities such as comprehensive soil and water loss control are the main driving factors that cause runoff and sediment load changes in the basin, which indicates that the comprehensive soil and water conser vation control in the Hantaichuan basin has achieved remarkable results since the 1990s. [ABSTRACT FROM AUTHOR]

Among the anthropogenic disturbances that affect rivers, artisanal and small-scale gold mining (ASGM) has recently generated great concern regarding the deterioration of aquatic ecosystems. This study aimed to evaluate the impact of ASGM on the assemblages of aquatic insects. For this, aquatic insects were sampled from two actively mined streams in the Osa Peninsula in Costa Rica. ASGM produces significant changes in the richness, abundance and assemblage's composition of aquatic insects. These changes, however, are mitigated a few meters downstream, after encountering a seemingly undisturbed tributary, for which the stream seems to keep its stability through resilience. For ASGM activities that have low intensities of extraction and don't use pollutant chemicals for amalgamation, keeping a low intensity of the activity and a considerable distance between goldmining sites could be an option for a more sustainable development of this activity, since it allows biodiversity to be partially restored. [ABSTRACT FROM AUTHOR]

This document discusses the challenges faced by White Sturgeon in California, including droughts, habitat loss, and warming water conditions. The California Department of Fish and Wildlife conducted a rescue and monitoring effort to relocate sturgeon from the Tuolumne River to the San Joaquin River to protect their health and reduce the risk of poaching. Acoustic monitoring was used to track the sturgeon's movements after relocation. The document also provides information on a separate monitoring effort in the San Joaquin River and its tributaries, where three sturgeon were tagged and monitored to understand their habitat use and migration patterns. The document acknowledges the individuals and organizations involved in the monitoring effort and provides additional references for further research. [Extracted from the article]

For a channel with a constant discharge, the characteristics of the surge wave entering a junction are obtained from the classical Stoker solution, and then the effect of the junction is analysed by applying the momentum and mass conservation equations. Experimental cases involving different combinations of the tributary lake height and the main channel discharge were tested, and measurements show good agreement with the theoretical solution. The experiments showed that the initial lake height and initial velocity in the main channel influence the surge wave characteristics. The ratio between the Reynolds number in the lake and in the main channel can be used to predict time to peak and peak flow rate. Furthermore, power-law relations for surge wave height and velocity downstream of the junction were developed from the analytical solution. [ABSTRACT FROM AUTHOR]

Tributaries are one of the most important factors contributing to variability in the downstream evolution of bed sediment grain size. The primary aim of this work is to evaluate the response of the bed sediment texture in the recipient channel induced by ten tributaries of the Černá Ostravice stream and find reach-scale and catchment-scale parameters that would be able to predict this response. The research was based on collecting information on the grain size distributions at sites adjacent to confluence zones. A significant change in sediment texture occurred in the vicinity of five confluences. Considering the other factors contributing to grain size variability (e.g., local channel geometry, lithology, and lateral sediment sources), it was assumed that only four of them were associated with a sufficient bedload influx to alter the sediment calibre below the junction. Moreover, a significant morphological effect in the form of a large confluence bar was observed in one case. These tributaries had several common features: (i) they had a larger relative catchment area than that of nonsignificant tributaries; (ii) they were characterized by different bed grain sizes, with some exceptions; and (iii) they had a higher unit stream power close to the confluence in relation to that of the mainstream. These characteristics were represented by the proposed relative parameters, including the relative unit stream power and bed material texture, which allowed the best classification of significant and nonsignificant tributaries. In their simplified form, the parameters described the transport capacity and grain size distribution, which were generally considered to be primary factors responsible for a redefinition of the sediment texture in the recipient channel. However, it should be noted that these results are subject to some degree of uncertainty due to the relatively small sample size of only 10 tributaries. [ABSTRACT FROM AUTHOR]

Lake Xingyun is a hypertrophic shallow lake on the Yunnan Plateau of China. Its water quality (WQ) has degraded severely during the past three decades with catchment development. To better understand the external nutrient loading impacts on WQ, we measured nutrient concentrations in the main tributaries during January 2010–April 2018 and modelled the monthly volume of all the tributaries for the same period. The results show annual inputs of total nitrogen (TN) had higher variability than total phosphorus (TP). The multi-year average load was 183.8 t/year for TN and 23.3 t/year for TP during 2010–2017. The average TN and TP loads for 2010–2017 were 36.6% higher and 63.8% lower, respectively, compared with observations in 1999. The seasonal patterns of TN and TP external loading showed some similarity, with the highest loading during the wet season and the lowest during the dry season. Loads in spring, summer, autumn, winter, and the wet season (May–October) accounted for 14.2%, 48.8%, 30.3%, 6.7%, and 84.9% of the annual TN load and 14.1%, 49.8%, 28.1%, 8%, and 84.0% of the annual TP load during 2010–2017. In-lake TN and TP concentrations followed a pattern similar to the external loading. The poor correlation between in-lake nutrient concentrations and tributary nutrient inputs at monthly and annual time scales suggests both external loading and internal loading were contributing to the lake eutrophication. Although effective lake restoration will require reducing nutrient losses from catchment agriculture, there may be a need to address a reduction of internal loads through sediment dredging or capping, geochemical engineering, or other effective measures. In addition, the method of producing monthly tributary inflows based on rainfall data in this paper might be useful for estimating runoff at other lakes.

Excessive nitrogen (N) and phosphorus (P) loading is one of the greatest threats to aquatic ecosystems in the Anthropocene, causing eutrophication of rivers, lakes, and marine coastlines worldwide. For lakes across the United States, eutrophication is driven largely by nonpoint nutrient sources from tributaries that drain surrounding watersheds. Decades of monitoring and regulatory efforts have paid little attention to small tributaries of large water bodies, despite their ubiquity and potential local importance. We used a snapshot of nutrient inputs from nearly all tributaries of Lake Michigan--the world's fifth largest freshwater lake by volume--to determine how land cover and dams alter nutrient inputs across watershed sizes. Loads, concentrations, stoichiometry (N:P), and bioavailability (percentage dissolved inorganic nutrients) varied by orders of magnitude among tributaries, creating a mosaic of coastal nutrient inputs. The 6 largest of 235 tributaries accounted for ~70% of the daily N and P delivered to Lake Michigan. However, small tributaries exhibited nutrient loads that were high for their size and biased toward dissolved inorganic forms. Higher bioavailability of nutrients from small watersheds suggests greater potential to fuel algal blooms in coastal areas, especially given the likelihood that their plumes become trapped and then overlap in the nearshore zone. Our findings reveal an underappreciated role that small streams may play in driving coastal eutrophication in large water bodies. Although they represent only a modest proportion of lake-wide loads, expanding nutrient management efforts to address smaller watersheds could reduce the ecological impacts of nutrient loading on valuable nearshore ecosystems. [ABSTRACT FROM AUTHOR]

The effect of river flood on the channel and settlements is discussed. The insufficiency of cleaning the channel to increase the river capacity and the shortcomings of the effect of the river dikes on the channel are justified. It is proposed to use flood-control dams (rapids) on tributaries for detention of floodwaters in the flood formation zone. [ABSTRACT FROM AUTHOR]

Data on Secchi depth, chlorophyll a , total phosphorus (TP), and nutrient status of phytoplankton were collected at five nearshore sites (11–17 m deep) and two offshore sites (>100 m) between the Grand River and Muskegon River outflows during March-December 2014–2018 to describe seasonal patterns and to compare the two depth regions in southeastern Lake Michigan. In contrast to the offshore, where spring chlorophyll a and TP concentrations declined dramatically following the dreissenid mussel expansion, the nearshore region of southeastern Lake Michigan was still characterized by low Secchi depth and elevated chlorophyll a and TP in the spring. During May, median Secchi depth was 5 times higher in the offshore than the nearshore, whereas chlorophyll a and TP were over 9 and 3 times higher in the nearshore, respectively. Even though spring chlorophyll a and TP have declined substantially at some of the nearshore sites compared to 1996, particularly the sites closest to tributary outflows, the overall yield of chlorophyll a per unit TP did not change over time in the nearshore. There were indications of P-deficiency in the nearshore in 2014–2018, but P-deficiency was even more severe in the offshore during the spring where yield of chlorophyll a per unit TP was also lower than in the nearshore. Although dreissenid mussels can be abundant in the nearshore, their populations are patchy and inputs from tributaries provide conditions that apparently dampen any potential filtering impacts of mussels in the nearshore compared to the offshore, especially during the spring. [ABSTRACT FROM AUTHOR]

The Red Power movement of the 1960s and 1970s was not universally endorsed and accepted by all Native communities, particularly in areas where other forms of indigenous accommodation and resistance to settler colonialism had already developed long-term strategies. The situation in the U.S. South was complicated by issues of race, and must be understood in the historical context of, first, slavery, and subsequently, Jim Crow. In these systems, activism by non-White populations carried different meanings within the wider political economy of the region. Understanding the push and pull factors of a desegregating South is required to explain Virginia's mid-century indigenous political landscape. Attention should be given to the various and multiple reasons for Native community action in each specific context, especially to race-based civil rights activism within a state where the Eugenics Movement, Racial Integrity, and the 'one drop rule' had historically loomed large. Like other states across the South, the Commonwealth of Virginia officially recognised eleven tribes of 'Virginia Indians' between 1983 and 2010, an outcome of post-Red Power indigenous political activism. Virginia tribes' political positioning during the civil rights era requires an analysis that historically situates their long-term alliance building and strategic essentialism as alternative approaches to those that were promoted by Red Power. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine the distribution of prevailing forest types within the catchment areas of the biggest rivers in the north-east of Ukraine. During the allocation of the catchment areas of the studied rivers, the MapInfo Professional 12.5 program and the vector map of Ukraine were used. The research covered the forest area (more than 502,000 ha) of the state forest enterprises managed by the State Forest Resources Agency of Ukraine. The studied area located on the tributaries of the Sula, Psel, Vorskla and Siversky Donets rivers within the Poltava, Kharkiv, Sumy, Chernihiv, Kyiv and Cherkasy administrative regions of Ukraine. The analysis of the forest fund was carried out based on the electronic subcompartment database of the Ukrderzhlisproekt Production Association, using the application software and geoinformation technologies. It was revealed that a large variety of forest types in the tributaries of the Sula, Psel, Vorskla and Siversky Donets rivers as well as the prevalence of fresh fertile maple-lime oak and fresh fairly infertile oak-pine forest types (in 75 tributaries of Psel, Vorskla and Siversky Donets rivers) and fresh fertile maple-lime oak and fresh fertile hornbeam oak forest types (in 20 tributaries of the Sula River) are due to the relief, hydrological and soil-climatic conditions of the studied area, as well as anthropogenic factor. Assuming homogeneous natural conditions, an insignificant number of forest types are formed (up to five). For a large variety of natural conditions, there are at least six forest types that should be taken into account during forest management, along with the characteristics of the catchment areas of tributaries. The analysed data on the total number of forest types in the catchments of rivers would be appropriate to use in the future when creating a single list of forest types for the Left-Bank Forest-Steppe zone of Ukraine. The prevalence of certain forest types within the catchment areas of tributaries of the Sula, Psel, Vorskla and Siversky Donets rivers directly depends on the soil and climatic conditions, geomorphological structure, relief and anthropogenic influence in the forests. The results should be used in forest management activities to preserve and restore the species diversity of forests within the river catchments. [ABSTRACT FROM AUTHOR]