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Improving the environmental quality of effluent‐dominated seasonal rivers is a fundamental challenge for sustaining life in drylands, where people utilize contaminated water to produce food, which ultimately accumulates in the food chain. Preventing further contaminations and phytoremediation are needed to avoid environmental degradation and health risks. This study aimed at analysing water quality and its impacts on soil and vegetation at effluent‐impacted, river‐edge and non‐polluted (control) micro‐habitats at five sites along Luni, Bandi and Jojari Rivers each in western Rajasthan. Soil and water samples were collected and analysed, and vegetation was recorded. River water exhibited high pH (7.60–8.60), electrical conductivity (EC; 2.45–38.20 dS m−1), total dissolved solid (TDS; 1.26–30.86 g L−1), alkalinity (24.0–250.0 mg L−1) and Na (1.50–30.00 g L−1), K (29.0–1100.0 mg L−1), Ca (136.0–3800.0 mg L−1) and Mn (0.05–83.92 mg L−1) concentrations and low NH4‐N, NO3‐N, PO4‐P and heavy metals. Species numbers ranged between 32 along Luni and 20 along Jojari. Soil pH, EC, PO4‐P and shrub richness (R), diversity (H′) and evenness (e') were highest for Bandi, whereas NH4‐N, NO3‐N, K and tree R and H′ were highest for Jojari River. Soil variables decreased and plant diversity increased downstream. Concentrations of Cd, Zn, Cr, Cu and Pb were above the acceptable limit in leaf of Salvadora persica and Prosopis juliflora. Principal component analysis (PCA) revealed significant relationships between different variables of river water, soil, and vegetation and 11 PCA axes. Conclusively, industry effluents negatively affected water, soil and river ecology. Effluent‐impacted soils had high salinity and less diversity adapted by salt‐tolerant species, complementary effects of which contribute to restoring the modified ecosystem and urban greening. Although people utilize effluent‐contaminated water in irrigation, precautions should be taken to avoid environmental and animal/human health risks. Highlights: Water quality and vegetation diversity were assessed for effluent‐dominated Luni, Bandi, and Jojari Rivers.Low‐quality water from effluent‐dominated rivers enhanced soil pH, EC, PO4‐P, and reduced vegetation diversity.Effluent‐inflicted area was dominated by herbaceous vegetation tolerant to high salt and saline water.Species appearing in new habitats can be utilized in restoring and greening such degraded areas. [ABSTRACT FROM AUTHOR]

Abstract\nNOVELTY STATEMENTA major data gap in tropical river ecology is the limited documentation of natural water purification of upstream rivers. This study documented the improvement of water quality of downstream Balili River as affected by environmental factors and macrophyte diversity using a mixed-method approach (water quality assessment, plant inventory, field observation, canonical correspondence analysis, community interview). Results showed that the distance from pollution plays a significant role in the self-purification of the river while the floral diversity maintains the riparian from further contaminating the water and at the same time absorbing air pollutants. Generally, the pollution reduction and %change is exponential at 2 and 3 km from point source then taper at 4 and 5 km. At 3 km from the point source, 30% improvement in TDS, BOD and salinity, 25% for EC, 20% in TSS, 35% in WQI, 36% in CPI, and 50% for DO were noted. Key factors that influence the self-purification process in the river were distance from pollution source, elevation, human disturbance (as indicated by %tree canopy) and temperature. These findings highlight the importance of distance from pollution sources and floral diversity in driving water quality improvements, with implications for sustainable water resource management in tropical regions.This study documented the improvement of water quality of downstream Balili River as affected by environmental factors and macrophyte diversity – as contribution to the major data gap in tropical river ecology which currently has limited documentation on natural water purification of upstream rivers. The study also shows the mosaic interplay of water quality, plant diversity, distance from pollution, human disturbance, and air quality in understudied tropical river. Further, this study is unique in documenting the downstream of Balili River since majority of the previous studies were concentrated in the upstream portion of the river. [ABSTRACT FROM AUTHOR]

Climate change elevates the threat of compound heat and drought events, with their ecological and socioeconomic impacts exacerbated by human ecosystem alterations such as eutrophication, salinization, and river engineering. Here, we study how multiple stressors produced an environmental disaster in a large European river, the Oder River, where a toxic bloom of the brackish-water planktonic haptophyte Prymnesium parvum (the "golden algae") killed approximately 1000 metric tons of fish and most mussels and snails. We uncovered the complexity of this event using hydroclimatic data, remote sensing, cell counts, hydrochemical and toxin analyses, and genetics. After incubation in impounded upstream channels with drastically elevated concentrations of salts and nutrients, only a critical combination of chronic salt and nutrient pollution, acute high water temperatures, and low river discharge during a heatwave enabled the riverine mass proliferation of B-type P. parvum along a 500 km river section. The dramatic losses of large filter feeders and the spreading of vegetative cells and resting stages make the system more susceptible to new harmful algal blooms. Our findings show that global warming, water use intensification, and chronic ecosystem pollution could increase likelihood and severity of such compound ecoclimatic events, necessitating consideration in future impact models. [ABSTRACT FROM AUTHOR]

The Hailar River is located in the Inner Mongolia Autonomous Region of Northeast China. It is a connecting hub of the agricultural pastoral transitional zone on the Hulunbuir grassland, with abundant water and biodiversity resources, and important ecological conservation significance. This study takes the Hailar River as the research area to evaluate the impact and main influencing factors of soil C, N, and P ecological measurement from the upstream to downstream concave convex riverbanks of the Hailar River. The research results show that: (1) The average soil particle size shows differences in the upstream and downstream: the average soil particle size in Section 1 is 31.6–192.3 µm, Section 2 is 21–213 µm, Section 3 is 21–288 µm, and Section 4 is 42–206 µm; the pH value in the upstream area is generally low, while the pH value in the downstream area increases. The reason for this is that the convex bank area has sufficient water, which plays a role in inhibiting salt content; (2) the nutrient content in the concave bank is generally higher in the upstream region than in the downstream region, while the difference in nutrient content between the upstream and downstream regions is relatively small in the convex bank; (3) the nutrient content of concave banks is mostly positively correlated with soil moisture content, while convex banks are positively and negatively correlated with soil moisture content and soil particle size. Research has shown that different cross-sections upstream and downstream, as well as uneven riverbanks, significantly affect soil physicochemical properties and soil C, N, and P ecological measurements. Studying the content of soil C, N, and P in different riparian zones under typical cross-sections can provide new ideas for regional ecological protection and even global C, N, and P cycling. [ABSTRACT FROM AUTHOR]

Riverbed elevations play a crucial role in sediment transport and flow resistance, making it essential to understand and quantify their effects. This knowledge is vital for various fields, including river engineering and stream ecology. Previous observations have revealed that fluctuations in the bed surface can exhibit both multifractal and monofractal behaviors. Specifically, the probability distribution function (PDF) of elevation increments may transition from Laplace (two‐sided exponential) to Gaussian with increasing scales or consistently remain Gaussian, respectively. These differences at the finest timescale lead to distinct patterns of bedload particle exchange with the bed surface, thereby influencing particle resting times and streamwise transport. In this paper, we utilize the fractional Laplace motion (FLM) model to analyze riverbed elevation series, demonstrating its capability to capture both mono‐ and multi‐fractal behaviors. Our focus is on studying the resting time distribution of bedload particles during downstream transport, with the FLM model primarily parameterized based on the Laplace distribution of increments PDF at the finest timescale. Resting times are extracted from the bed elevation series by identifying pairs of adjacent deposition and entrainment events at the same elevation. We demonstrate that in cases of insufficient data series length, the FLM model robustly estimates the tail exponent of the resting time distribution. Notably, the tail of the exceedance probability distribution of resting times is much heavier for experimental measurements displaying Laplace increments PDF at the finest scale, compared to previous studies observing Gaussian PDF for bed elevation. Plain Language Summary: The evolution of riverbed elevations is difficult to describe due to its highly variable and strongly non‐linear nature. Understanding and quantifying the dynamics of riverbed elevations are important for river engineering and stream ecology, and serve as the basis for numerical models of predicting sediment transport as well as interpreting stratigraphy from the past records. Through laboratory experiments, we have observed that the form of elevation increment PDF can change from Laplace to Gaussian as the timescale increases. This phenomenon is successfully modeled in this paper for the first time by the fractional Laplace motion, which essentially generates bed elevation series for the evolution of bed surface height at a certain spatial location of the bed. This series contains information on how long a bedload particle can rest (resting time) in the riverbed before it can be re‐entrained to move downstream, the determination of which by other means (e.g., particle‐tracking measurements) is challenging. By extracting resting times embedded in this bed elevation series, we obtain statistics (i.e., the tail behavior of the resting time distribution) that are key for correctly modeling the transport of bedload particles, and more specifically, that can help us to understand the anomalous bedload diffusion process. Key Points: The Fractional Laplace motion (FLM) can be used to describe the evolution of the distribution of bed elevation increments over different timescalesCorrectly predicting bed elevation fluctuations at the finest timescale is critical for estimating resting times for bedload tracer transportFLM model provides a means of robustly estimating the tail exponent of the resting time distribution in case of insufficient data series length [ABSTRACT FROM AUTHOR]

Headwater streams are critical, fragile ecosystems that supply food and nutrients for an array of organisms that are vital to the overall health of a stream. As the dominant vertebrates in headwater streams of the southern Appalachian Mountains, plethodontid salamanders are critical to healthy headwater communities. However, a neglected feature of these ecosystems is the community of parasites that infect salamanders. The digenetic trematode Metagonimoides oregonensis uses the aquatic snail Elimia proxima as its first intermediate host and the plethodontid salamander Desmognathus amphileucus as its second intermediate host. In a series of southern Appalachian streams, we tested the hypothesis that variance in the prevalence and intensity of infection in salamander hosts is related to respective densities of the snail and salamander species. Infection prevalence was 100% across all streams. There was a strong relationship between the density of the snail host and infection-intensity level in the salamander host. However, the relationship with salamander density was not important, a finding that conflicts with the results of parasitological studies involving lentic and marine systems. The influence of this trematode on the ecology of headwater streams and the resident salamanders has been underappreciated, and a number of aspects of this relationship remain unknown. [ABSTRACT FROM AUTHOR]

This paper moves across the ecological assemblages of the Periyar basin in Kerala. It argues that the connectivities and unintentional designs that emerge bespeak the Anthropocene in its regional and political peculiarities. The river has never been a conduit of water alone. The narrative builds broadly on ecological relations entrenched in history, most visibly as hydrological regimes. Such regimes are significant because of the riparian densities that articulate the geo‐morphology. The different entanglements in ecology, as well as the successive productions of natures, gain significance as 'recognitions' during rupture events like the large floods. In contemporary contexts, the versatile flows of capital dissolve markers and boundaries and reconfigure regions in terms of capital. Vikasanam or new urban reforms, apart from political policies, are also ecological designs that normalise exceptions, otherwise reserved for special economic zones. The frictions with new materiality, post dam floods and hydrological controls, during developmental and neoliberal post developmental phases, become moments of recognition, making and unmaking sense of place. [ABSTRACT FROM AUTHOR]

Habitat fragmentation is emerging as a leading cause of biodiversity decline in riverine ecosystems. Several natural and human factors contribute to the fragmentation of rivers. River fragmentation is a growing problem that is widely spread and poses a significant challenge to the conservation of freshwater biodiversity, but its impact is not fully documented and acknowledged. Fragmentation impedes the movement of aquatic organisms and alters natural flow regimes, disrupting habitats and trophic supplies for aquatic biodiversity. It can also affect the adaptive ability of organisms to natural environmental changes, leading to a change in the structure and function of biotic communities. To understand the effects of fragmentation on river ecology, it is crucial to link its spatial and structural implications. This article examines the occurrence and frequency of fragmentation and its effects on the ecological community of benthic biota. This review aims to elucidate the overall effects of fragmentation on river ecology and recommends the possible measures to mitigate its impact. Urgent action is required to establish a comprehensive global network of free‐flowing river systems and revive previously exploited rivers in different regions to enhance the protection and sustainable utilization of river ecosystems. [ABSTRACT FROM AUTHOR]

Agricultural water serves various functions, including public interest purposes, beyond its primary role in agricultural production. In order to evaluate the various public interest purposes of agricultural water, a quantified study of the effect of agricultural water on river flow, water quality, and aquatic ecosystems is needed. Therefore, this study quantified the impact of agricultural water on the environmental and ecological maintenance function of downstream rivers, taking into account the return flow of agricultural water in rural areas. To this end, first, the effect of agricultural return flow on river maintenance function was evaluated by comparing the return flow quantity calculated using the reservoir supply data with the simulated river flow rate through the SWAT model. Second, the effect of the agricultural return flow on the downstream river environmental ecological function was analyzed using the optimal flow rate results calculated through the PHABSIM model. The lastly, the effect of agricultural water by farming period on the water quality of downstream rivers was analyzed. As a result of the analysis, it was found that the return flow of agricultural water had a large effect on the river flow rate in the case of the non-rainy season, but the optimal ecological flow rate was not satisfied. In the case of river water quality, it was confirmed that the effect of agricultural water (mainly considered as a pollutant) was not significant, except for the drainage duration of rice paddies. Therefore, it can be understood that agricultural water is not only used for the purpose of production but can also have a positive impact on the aquatic ecology of downstream rivers. [ABSTRACT FROM AUTHOR]

Benthic algae and autotrophic seston are important bases of stream food webs, and several different environmental factors may influence their biomass. We explored how benthic algae and autotrophic seston biomass (using chlorophyll-a as a proxy for algal biomass) were associated with stream temperature, channel width, canopy cover, stream cardinal orientation, benthic macroinvertebrate functional feeding group abundance, salmonid biomass, and water velocity in 16 small, fish-bearing streams in the temperate rainforest of the Olympic Peninsula in Washington State, USA, in the summer of 2020. We performed a mixed-effects regression analysis of extracted chlorophyll-a (chl-a) and then used model averaging to determine significant (α = 0.05) algal–environmental associations for benthic algae and autotrophic seston separately. We found that benthic algae chl-a concentration increased significantly with stream temperature (p = 0.0085) and decreased significantly with water velocity (p = 0.0053). For autotrophic seston, we found that chl-a concentration increased significantly with benthic macroinvertebrate predator abundance (p = 0.0007) and stream temperature (p = 0.0160). This study underscores the need to consider a broad range of environmental variables when making research and management decisions concerning stream ecology. [ABSTRACT FROM AUTHOR]

Conservation of embankment soil along the rivers is a global challenge. The existing solutions including rigid structures and cement-based techniques pose risks to the sensitive river ecology. The trending biopolymer (Bp) based soil stabilisation technique has shown enormous potential to stabilise loose and soft soils. The rheology of such biopolymer solutions is expected to play a critical role in soil stabilisation, especially in a wet environment such as riverbanks. In this study, four different levels of xanthan gum treatment (0.5 to 1.25% by soil weight) are investigated for stabilising the soil collected from an erosion-prone bank of the Brahmaputra River basin. The rheological properties of the intended biopolymer solutions are investigated extensively prior to their application. Later, the degree of stabilisation of the biopolymer-treated soil is determined by evaluating their unconfined compressive strength (UCS) and secant modulus. The erosion characteristics of the treated samples were evaluated using an in-house built apparatus. The shear-thinning and viscoelastic parameters of the biopolymer solutions have been quantified with the rheological analysis. The UCS strength test revealed a consistent increase up to 1.6 MPa with an increase in the biopolymer treatment of 1.25%. The erosion test revealed that the biopolymer treatment delayed the erosion process. However, it did not completely cease the erosion. The microstructure analysis revealed that the strong biopolymer bridging acts as a dampener in the soil pores to delay erosion. This study unravels the critical role of rheological factors, which are essential in reproducing the desired results from the geotechnical laboratories to field-scale applications. [ABSTRACT FROM AUTHOR]

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.)

Low‐flow events, characterized by a significant water deficiency in river systems, have profound impacts on various water users and river ecology. Recent low‐flow events in Europe have had severe economic and ecological consequences such as disruptions to hydropower production, irrigation bans, constraints on navigation and complete river drying. These events highlight the urgent need for effective low‐flow risk management and demand a holistic risk analysis as a basis. The existing approaches to low‐flow analysis often focus on hydrological aspects, utilizing indices such as the Standardized Runoff Index (SRI) or Low‐flow Index. However, these indices lack information regarding consequences and impacts. Other approaches consider parts of a risk approach but often focus on special aspects, such as the economy; in general, no holistic assessment is made. This study introduces a conceptual approach to a holistic low‐flow risk analysis. The approach provides a continuous long‐term simulation to capture the special long‐term behaviour of low‐flow events and therefore avoids the complex definition of scenarios. In this conceptual approach, the low‐flow risk is analysed using a combination of various analyses that cover all aspects from occurrence to consequences. Meteorological analysis is used to generate synthetic long‐term weather data time series, which are transformed into runoff time series in hydrological analysis. Based on these results, hydrodynamic analysis quantifies the water levels, water temperatures, and flow velocities along the river. The consequences are analysed in terms of socio‐economic and ecological consequences. The results represent a long‐term series of damage values. Finally, the damage values are summed in the risk analysis and divided by the number of years considered in the analysis. For testing and demonstration purposes, the presented conceptual risk approach is partly applied to a proof‐of‐concept at the Selke catchment, a small river catchment in Germany. Finally, the results are presented, evaluated, and discussed. [ABSTRACT FROM AUTHOR]

Abstract Climate change elevates the threat of compound heat and drought events, with their ecological and socioeconomic impacts exacerbated by human ecosystem alterations such as eutrophication, salinization, and river engineering. Here, we study how multiple stressors produced an environmental disaster in a large European river, the Oder River, where a toxic bloom of the brackish-water planktonic haptophyte Prymnesium parvum (the “golden algae”) killed approximately 1000 metric tons of fish and most mussels and snails. We uncovered the complexity of this event using hydroclimatic data, remote sensing, cell counts, hydrochemical and toxin analyses, and genetics. After incubation in impounded upstream channels with drastically elevated concentrations of salts and nutrients, only a critical combination of chronic salt and nutrient pollution, acute high water temperatures, and low river discharge during a heatwave enabled the riverine mass proliferation of B-type P. parvum along a 500 km river section. The dramatic losses of large filter feeders and the spreading of vegetative cells and resting stages make the system more susceptible to new harmful algal blooms. Our findings show that global warming, water use intensification, and chronic ecosystem pollution could increase likelihood and severity of such compound ecoclimatic events, necessitating consideration in future impact models.

Freshwater salinization increasingly threatens river ecosystems in arid regions. In situ studies on effects of salinity on freshwater communities are still scarce, especially in largely understudied areas of Africa. To compare macroinvertebrate communities in differing salinity levels, we conducted a confluence-based study in the Draa River basin in Morocco by focusing on two tributaries and their joint downstream sections, in the immediate vicinity of three confluences. Our study revealed that α-diversity differed only minimal. Although only around five taxa comprised over 90% of specimens per section, the more saline sections exhibited proportionally more salt-tolerant generalist species. There was lower β-diversity between the downstream section and each tributary compared to between tributaries, indicating a mixed community after the confluence. The trait profile of the saline El Mellah displayed more resistance and resilience traits to disturbances than the less saline Iriri. Furthermore, low water flow reduced the abundance of sensitive taxa. Overall, we observed minimal differences in macroinvertebrate community composition, due to low γ-diversity in the basin. However, the confluence-based study design remains valuable for investigating effects of specific stressors on ecosystems by excluding large-scale geographic patterns, as compared sites are close and therefore share the same climate, geology, and altitude. [ABSTRACT FROM AUTHOR]

The article announces the 2023 class of Fellows for the American Association for the Advancement of Science (AAAS), recognizing 502 members for their contributions to science and society.

River typology is determined by a set of hydrological and geomorphological characteristics, which can determine the structure of aquatic macroinvertebrate communities throughout a watershed. In this study we aim to address the gap of knowledge in the classification of the typology of Neotropical rivers and determine their association with macroinvertebrate assemblages. In total, 138 sites from 107 rivers were sampled in Costa Rica, between years 2015 and 2020. Rivers were classified into V, Tr and U typologies based on the shape of the riverbed, substrates, current velocity and contact with riparian forest. The affinity of aquatic macroinvertebrate taxa to each typology was determined. The results confirmed a clear separation of the aquatic macroinvertebrate assemblages between the typologies, and we observed that some genera showed affinity to a specific typology: Macrobrachium and Caenis are related to U-type; Simulium and Anacroneuria to V-type, while Americabaetis and Thraulodes to Tr-type. This separation was related to in-stream habitat supply and substrate characteristics, yet there was an overlap of shared taxa between the V and Tr-type, and between the Tr and U-type. Our study linked 238 taxa to three river typologies, highlighting the importance of river hydrogeomorphology as a robust factor structuring the macroinvertebrate assemblages in tropical streams. River channel typology should be considered a relevant explanatory variable when studying macroinvertebrate responses, not only within ecological studies, but also for biomonitoring and risk assessment related to land use changes, pollution, or watershed management. [ABSTRACT FROM AUTHOR]

Understanding the impacts of habitat modification on primate feeding ecology is essential to design effective conservation management strategies. The dietary guild (e.g., frugivore, folivore, insectivore, and omnivore) of primates and their degree of ecological flexibility impacts their ability to cope with human-modified habitats. The Omo River guereza (Colobus guereza guereza) is a subspecies of eastern black-and-white colobus monkey endemic to the western Rift Valley forests of Ethiopia, where it faces increasing anthropogenic change. While there is some understanding of how this subspecies copes with anthropogenic pressures, we compared the feeding ecology of Omo River guerezas in natural and human-modified habitats. Specifically, we collected data on two neighbouring guereza groups that inhabit adjacent plantation and natural forest habitats over 12 months in Wof-Washa Natural State Forest in the central highlands of Ethiopia. Furthermore, we conducted vegetation surveys on the botanical composition and vertical structure of both habitat types. The monthly food availability index of young leaves was higher in the natural forest than in plantation forest habitat. We observed guerezas feeding on 30 plant species in the natural forest but only 18 species in the plantation forest. Guerezas in both forest types consumed mostly young leaves, but the natural forest group relied more on mature leaves and shoots, and less on fruits and stems, than the plantation forest group. Maesa lanceolata leaves contributed a greater proportion of the overall diet for the plantation forest group, whereas Vernonia leopoldi accounted for the largest proportion of the guereza diet for the natural forest group. The top five species consumed comprised 83% of the diet in the plantation forest group and 70% in the natural forest group, indicating that relatively few plant species dominate guereza diets in these habitats. Conservation of both natural and plantation forests, especially the plant species most intensively exploited by guerezas, should be prioritized to assist in Omo River guereza conservation efforts. [ABSTRACT FROM AUTHOR]

Copyright of Österreichische Wasser- und Abfallwirtschaft is the property of Springer Nature 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.)

Chinese plum (Prunus salicina) cv. Wushancuili has a green coloration, high fruit quality, and is economically important in eliminating poverty and protecting ecology in the Yangtze River Three Gorges Reservoir. However, large-scale production and synchronous ripening times present a huge postharvest storage challenge. This study investigated the effect of different postharvest storage temperatures on the 'Wushancuili' plum fruit flavor. The dynamics of soluble sugars, organic acids, and aroma substances were investigated at four temperatures mimicking large-scale commercial storage applications: 0–2 °C, 4–6 °C, 8–10 °C, and 20 °C, for 0, 3, 5, 7, 10, 15, and 20 days. Storage under the 0–2 °C regime was the best at preserving fruit flavor and reducing decay compared to the other settings. At 0–2 °C, fruit maintained a stable level of soluble sugars and organic acids during storage. Moreover, this storage temperature facilitated the formation of aroma compounds such as alcohols, aldehydes, ketones, and acids, which contributed to the distinct fruit aromatic characteristics. Taken together, our findings indicate that 0–2 °C is the most favorable temperature for commercial storage and maintenance of the 'Wushancuili' plum flavor. [ABSTRACT FROM AUTHOR]

Scale invariance, which refers to the preservation of geometric properties regardless of observation scale, is a prevalent phenomenon in ecological systems. This concept is closely associated with fractals, and river networks serve as prime examples of fractal systems. Quantifying river network complexity is crucial for unveiling the role of river fractals in riverine ecological dynamics, and researchers have used a metric of "branching probability" to do so. Previous studies showed that this metric reflects the fractal nature of river networks. However, a recent article by Carraro and Altermatt (2022) contradicted this classical observation and concluded that branching probability is "scale dependent." I dispute this claim and argue that their major conclusion is derived merely from their misconception of scale invariance. Their analysis in the original article (fig. 3a) provided evidence that branching probability is scale‐invariant (i.e., branching probability exhibits a power‐law scaling), although the authors erroneously interpreted this result as a sign of scale dependence. In this article, I re‐introduce the definition of scale invariance and show that branching probability meets this definition. This provided an opportunity to address the divergent use of "scale invariance" and "scaling" between fractal theory and ecology. [ABSTRACT FROM AUTHOR]

Reservoir ecological dispatching is a complex system problem involving multiple objectives, multiple criteria and multiple phases. This study established a multiobjective ecological dispatching model of the Yinma River Basin in Changchun city based on the water demand, socioeconomic development, river ecology, and constraints on reservoir characteristic parameters. Taking advantage of particle swarm optimization (PSO) and genetic algorithm (GA), a PSO-GA hybrid algorithm is proposed and applied to solve the schemes of ecological dispatching models considering different ecological flow requirements. The annual mean scheduling results show that the three scheduling schemes basically achieve the objectives of river ecological base flow scheduling. For ecologically suitable flows, the guaranteed rates for the RGOS1, RGOS2, and RGOS3 schedules at the Dehui section were 78.35%, 86.36%, and 95.98%, respectively, whereas the rates were 81.77%, 90.13%, and 96.57%, respectively, at the Nong'an section. The scheduling results of typical years show that the water security situation in the study area is not optimal, but the river ecological environment can be considerably improved by reservoir ecological dispatching. Finally, the excellent performance of the hybrid PSO-GA proposed in this study is verified via comparison with other algorithms. The Pareto front optimized by the PSO-GA can dominate the Pareto front solutions of the other algorithms. The IGD (0.19) of the Pareto front optimized by the PSO-GA is the smallest, and the SP (0.83) and HV (0.93) are the largest, indicating better convergence and comprehensive performance. [ABSTRACT FROM AUTHOR]

Traditional river health assessment relies on limited water quality indices and representative organism activity, but does not comprehensively obtain biotic and abiotic information of the ecosystem. Here, we propose a new approach to evaluate the ecological and health risks of river aquatic ecosystems. First, detailed physicochemical and biological characterization of a river ecosystem can be obtained through pollutant determination (especially emerging pollutants) and DNA/RNA sequencing. Second, supervised machine learning can be applied to perform classification analysis of characterization data and ascertain river ecosystem ecology and health. Our proposed methodology transforms river ecosystem health assessment and can be applied in river management. [Display omitted] [ABSTRACT FROM AUTHOR]

This article presents the results of a study of zoobenthos of the Ural River in an area from the town of Verkhneuralsk to the city of Orenburg (about 1000 km) with sampling upstream and downstream of sources of anthropogenic impact: large cities, metallurgical plants, treatment facilities (TFs), and reservoirs. The degree of pollution was estimated using the Shannon and EPT indices, as well as the Woodiwiss index, an indicator that partially takes into account the first two indices. It is shown that the selected parameters decrease downstream of the sources of anthropogenic impact, thereby reflecting a decrease in the species diversity of benthic biocenoses and a decrease in the number of indicator species sensitive to pollution. Small streams are particularly affected; pools are subject to greater transformations than riffles. An integrated indicator of water quality based on biological parameters is proposed. It was used to rank all studied areas by the degree of pollution. It is shown that ten of the 23 studied river areas are assigned to the 1st class of water quality (conventionally clean areas), seven areas to the 2nd class (weakly polluted areas), three areas to the 4th class (dirty areas), and three areas to the 5th class (extremely dirty areas). This indicates that, despite multiple sources of pollution, the Ural River has a high self-purification capacity and most of the studied areas are quite clean and favorable for the habitation of benthic invertebrates. [ABSTRACT FROM AUTHOR]

Guilin is a typical representative of karst landform in South China. Because of its unique geographical landform and hydrological environment, Lijiang River Basin has received a certain degree of attention in field of ecology and sustainable development. Explore and visualize the hotspots and frontiers of Guilin Lijiang River Basin Ecology and Sustainable Development (GLRBESD) by using bibliometrics, CiteSpace, and VOSviewer. Results showed that number of published papers was in a fluctuating upward trend from 1992 to 2022 and from 2011 to 2022, respectively. Work of scholars in this field has been continuously strengthened and deepened, and overall scientific research results show an increasing trend. Research objects and topics are mainly aimed at the water resources, climate, and environment of GLRB Landscape ecology and SDG index construction. Research of GLRBESD-published documents has the characteristics of multi-disciplinary and interdisciplinary integration. High-frequency keywords in research field focus on ecotourism, ecological restoration, and sustainable development, mainly based on the research of ecotourism development. Impact of environmental factor changes and human activities on land use change in different periods is an important research topic. Core research field of GLRBESD on macro-scale can be divided into ESV and function, ecological compensation and ecotourism, ecological environment and ecological restoration, ecological network and ecological risk assessment, and sustainable development. This research provides systematic scientific research basis for enhancing sustainable development ability and ecosystem functions and services of World Natural Heritage Site. [ABSTRACT FROM AUTHOR]

This document is a preface to a special issue of the journal Hydrobiologia on the topic of stream ecology and environmental gradients. The preface explains that human activities have fragmented natural landscapes, leading to changes in environmental gradients and a decline in biodiversity. The document highlights the importance of understanding the effects of environmental gradients on aquatic communities and ecosystem services. The special issue includes 10 papers from authors of various nationalities, focusing on the effects of land use, vegetation cover, water pollution, and other disturbances on diatoms, macroinvertebrates, and fish communities. The studies demonstrate that environmental gradients can alter water quality, habitat availability, and the structure and composition of aquatic communities. The document concludes by expressing gratitude to the reviewers and authors who contributed to the special issue. [Extracted from the article]

This article explores fluvial forms of art and activism to reclaim new meanings of energy at a time when questions about the energy transition are central in geography studies and global environmental discourses. Departing from Serpent River Book by Carolina Caycedo, we propose affective, embodied, and creative entanglements to understand energy flows in river ecologies in Latin America for an exploration of energy geohumanities. We then discuss the methodology of this energy geohumanities project in our engagements with Caycedo's art, reflecting on our sedimentary writing and thinking process enacted throughout the article. By centering this article on what energies art conjures and releases in affective and political terms, we explore the meanings of doing energy geohumanities in the deployment of a poetics of embodied tensions between flow and containment and between aerial and immersive views that challenge the dichotomies of subject/object, nature/culture and geo/human. Through unfolding a "sedimentary blog writing" method based on geo-mimicry, we hope to make a case for how entangled thinking and writing offer a novel approach to examining the multiple meanings of energy beyond electricity in the extractive zones of hydro-modernity. [ABSTRACT FROM AUTHOR]

In urban and agricultural streams, assessing aquatic ecosystem health is critical due to widespread pollution. Traditional methods for evaluating attached diatoms crucial for ecosystem monitoring face limitations such as species misidentification and sample damage. This study was conducted in the Miho River within the Geum River system and highlights the effectiveness of environmental DNA (eDNA) techniques for more accurate and efficient genetic-based analysis than conventional microscopic analysis methods. When eDNA-based assessments were compared with traditional microscopic methods, this study found that eDNA analysis often revealed poorer ecosystem health. Notably, eDNA assessments showed a stronger correlation with phosphorus concentrations, underlining their precision and importance in ecological studies. These findings suggest that eDNA has potential as a valuable tool for comprehensive biomonitoring. However, the use of international genetic barcode databases in eDNA analysis could lead to the identification of unrecorded species in Korea. Therefore, this study recommends developing a localized genetic barcode database and constructing eDNA information through meta-barcoding, focusing on native species. This approach is crucial for enhancing the accuracy and applicability of eDNA-based health assessments in national biomonitoring efforts. [ABSTRACT FROM AUTHOR]

The gravel bed clogging, caused by infiltration and accumulation of fine sediment, degrades the river ecology. A proper understanding of the infiltration process, and underlying mechanism and causes, are necessary to take preventive measures. The process of fine sediment infiltration into static gravel bed is studied by distinguishing between bridging and percolation behaviours, as they affect the river ecology and physical processes occurring in the river system differently. However, several contradicting observations, concerning their occurrences, are reported. We employed the unresolved CFD–DEM method to simulate and investigate the infiltration process. The theoretical size ratios, corresponding to different geometrical configurations for a binary mixture of mono‐disperse spherical particles, representing bridging and percolation processes, are considered and simulated with and without flowing water effects. The effects of several turbulence models on the infiltration process are also studied. We found that fine sediment infiltration in fluvial deposits is mainly gravity‐dominated, supporting Cui's hypothesis that fine sediment infiltration through intra‐gravel flow is similar to fine sediment infiltration driven by gravity. In contrast to consensus in the field, our results demonstrate that the occurrences of different infiltration processes (bridging and percolation) seem to be independent of gravel bed thickness, rather depend only on the relative grain size distribution of fine sediment and gravel. However, a precise definition of a 'thick enough' gravel bed is necessary to distinguish between bridging and percolation behaviours. Here, we hypothesize a suitable gravel bed thickness, which might be regarded as a 'thick enough' gravel bed. [ABSTRACT FROM AUTHOR]

Accurate particle size distribution (PSD) measurements of suspended particulate matter (SPM) composed of flocs and aggregates are important to improve understanding of ecological and geomorphological processes, and for environmental engineering applications. PSDs can be measured in situ (in the field) using a submersible sensor, or ex situ (in the laboratory) using samples. The methodological choice is often guided by logistical factors, and the differences in PSDs acquired by in situ and ex situ measurements is of concern. In this study, a laser‐diffraction instrument (the LISST‐200X) was used to compare in situ and ex situ PSD measurements. Samples measured ex situ were stored for three consecutive weeks and measured each week in a laboratory using different stirrer speeds. We observed that ex situ measurements display a higher D50 (median particle size) than in situ measurements of the same sample (up to 613% larger, 112% on average). Our experiments show that the difference between in situ and ex situ measurements can be explained by flocculation of the riverine sediments during the first week of storage. During the subsequent ex situ measurements, the stirring results in a significantly lower D50. Ex situ measurements are therefore unsuitable for flocculated SPM. This study provides recommendations for optimizing PSD measurements by calculating the measurement times required to obtain robust PSD measurements (exceeding 3 min per sample), which are larger for field samples with coarser particles and wider PSDs. Plain Language Summary: Measurements of the size of particles suspended in a water column are important for understanding many processes related to river ecology and morphology. It is possible to measure these particles directly in the field using a submersible sensor (in situ), or by taking samples and transporting them to a laboratory (ex situ). The choice between these options often depends on logistics, with little recognition of the impact that this choice can have on the measurements. In this research, the differences between in situ and ex situ measurements are explored. We find that ex situ measured particle sizes are on average 112% larger than in situ measurements, which can be related to flocculation of the riverine particles. Flocs are a combination of mineral particles (such as silt or clay) and organic particles, forming larger aggregates. Our results show that flocs grow when a sample is taken to the laboratory and stored. During ex situ measurements, which involve stirring, they break apart. Ex situ measurements are therefore unsuitable for determining the natural particle size. We show how long a measurement should last to give a representative particle size. In situ, longer measurement periods are needed. Key Points: The D50, a generic way to parametrize particle size distributions (PSDs), is not an absolute number, but depends on the measurement methodDifferences between in situ and ex situ measured PSDs are caused by the ex situ alteration of flocculated particlesA robust PSD measurement with laser diffraction takes longer for coarser field samples with a wider distribution [ABSTRACT FROM AUTHOR]

Water conservation initiatives satisfy the demand for water supply, electricity generation, irrigation, and flood control. While helping humanity, they have also altered the ecosystem of natural rivers, impacted river ecology, disrupted river continuity, and jeopardized the existence of aquatic creatures in rivers. Studying the impacts of dam construction on rivers can enhance our knowledge of river ecological and environmental concerns and help sustain the health of river ecosystems, thereby realizing the harmony between humans and water in both theoretical and practical aspects. This study used bibliometrics and constructed an author-keyword 2-mode matrix network using Co-Occurrence software to identify the hotspots and research trend in eco-hydrology of dammed rivers. We identified 'FLOW' 'SEDIMENT' 'QUALITY' and 'MODEL' as the research hotspots in the ecological impact of dammed rivers, and combined the related literatures, we highlight the research progress in the four directions. Then the research shortcomings and prospect were discussed, including strengthening the monitoring and analysis of critical ecological variables, enhancing the hydrological monitoring density for small rivers, strengthening the research of relationship between eutrophication and zooplankton, establishing multiscale approaches, and combining multi-sources information technologies to improve parameter accuracy in the model research. [ABSTRACT FROM AUTHOR]

The fragile ecology of the Yellow River basin (YRB) is vulnerable to global warming and human activities. As the second largest river in China, the YRB covers the subhumid, semi‐arid, arid and alpine climate zones, with considerably spatial differences in vegetation cover (VC), thus demonstrating substantial variations in response to climate change. In this study, characteristics of VC variations in different climate zones of the YRB during 1982–2019 were analysed, impacts of climate change and human activities on VC variations were identified, and possible VC variations in the future were projected under different climate scenarios. Results show that NDVI in the YRB significantly increased at a rate of 2.3 × 10−3 year−1 from 1982 to 2019, especially in the middle reaches of the YRB. Temperature is the main driver of VC variations in the source region of the YRB (alpine zone), wherein the warming trend contributes to the greening. The internal variability of VC is also influenced by temperature, with a marginal effect of precipitation minus evaporation (P − E). In the middle and lower reaches of the YRB consisting of arid, semi‐arid, and subhumid zones, VC benefited only from the warming trend and had a less relationship with the internal variability of temperature, whereas the internal variability of VC was influenced by P − E and had a weaker relationship with the P − E trend. Contributions of climate change to VC variations in the source region and middle and lower reaches of the YRB are approximately 62%, 42%, and 27%, respectively. Human activities considerably impact the ecological environment but mostly play a positive role. In the future, VC will increase in the YRB, especially under the SSP5‐8.5 scenario, and VC reveals the most prominent changes in the lower reaches. This study suggests that climate change might be favourable to VC in YRB, and emphasizes that human activities should adapt to climate change in an orderly manner. [ABSTRACT FROM AUTHOR]

The release and chemical fraction of cadmium (Cd) in sediment have a crucial influence on the ecology of rivers. Rivers containing large amounts of humic acid (HA) with the rapid development of industry and agriculture increase the solubility of Cd enhancing the bioavailability of Cd in sediments. Therefore, the possible interactions among influencing factors for the release and chemical fraction of Cd in sediments, such as HA concentration, pH, leaching time and molecular weight (Mw) of HA were investigated by using the European Community Bureau of Reference (BCR) sequential extraction procedure, ICP-OES, UV–Vis, FTIR and XRD technology. The quasi-equilibrium leaching time was 96 h, and the release rate of Cd in sediment decreased with increased pH from 3 to 7 and stabilized as pH increased from 8 to 10. It was also found that HA inhibited the release of Cd in sediment at pH 3 and 4, whereas at pH 5–10, HA promoted the release of Cd in sediment. The change in pH mainly affected the content of F1 and F2 for Cd in sediment. For > 100 kDa HA, the content of total Cd, F1 and F2 in sediment changed very little to a certain HA concentration (700 mg-C L−1 at the initial pH 6 and 350 mg-C L−1 at the maintained pH 6). For the Mw of 30–100 kDa HA, 10–30 kDa HA, and 1–10 kDa HA, the content of total Cd and F1 in the sediment decreased with the increase of HA concentration. For Mw < 1 kDa HA, the changes in HA concentration had little effect on the content and chemical fraction of Cd in the sediment. The Mw of > 100 kDa HA had effects on F1 and F2 of Cd in sediment, and the Mw of 30–100 kDa HA, 10–30 kDa HA, 1–10 kDa HA, < 1 kDa HA contributed only to F1 of Cd in sediment. The results demonstrated that the molecular weight of humic acid affected the release and chemical fraction of Cd in sediment. [ABSTRACT FROM AUTHOR]

This Perspective argues for an expansion of conventional concepts of river biomes to better encapsulate the emerging social understanding of 'biomes' as living systems with unique macro‐ and micro‐biotic ecological and biological signatures. We approach this by firstly examining recent interpretations of river biomes that have evolved from original zonal conceptions. We then postulate on the social/public understanding on 'biomes' through the popularity of two rich debates: human health via gut microbiomes and soil health via the soil microbiome. With these concepts in mind, we define the river biome as 'A living flowing aquatic ecosystem, indicative of its environmental context, comprising unique biological, ecological, hydrologic and health characteristics that shape and are shaped by macro‐ and micro‐biotic signatures and functions'. With this definition the term river biome is more aligned with ideas of river health and ecosystem functioning, which we believe may evoke greater public understanding of rivers as complex living systems. Enhanced public understanding of complex natural systems should be encouraged as a means by which to propel policy, funding and research as well as to improve specialist to non‐specialist communication and relations. [ABSTRACT FROM AUTHOR]

1.Dams on large rivers alter hydrodynamics, reduce seasonal variability and environmental heterogeneity, and have significant effects on river ecology. They produce less diverse environments and alter the community composition. Knowledge about the effects of dams on functional aspects of zooplankton communities is scarce. Thus, our main goal was to investigate how the zooplankton community of the Tocantins River in central Brazil changed after the implementation of the Estreito hydroelectric power plant dam. We explored the relationships of taxonomic and functional beta diversity in the zooplankton community, with the seasonality, flooding river phases and limnological variables.2.To answer our goals, we collected water samples 1 year before plant construction and 5 months after dam enclosure. To investigate how the environment changed after river damming, we conducted a principal component analysis. We calculated taxonomic and functional beta diversity using the Jaccard pairwise dissimilarity index for presence–absence data. To identify which functional traits were associated with each river phase and season, we firstly calculated the community weighted mean (CWM) for each trait. Secondly, we partitioned beta diversity into turnover and nestedness components. To investigate patterns of taxonomic and functional beta diversity and its turnover and nestedness components, we additionally used a series of six linear mixed models.3.Our results indicated that the limnological characteristics of the river changed after damming. Taxonomic and functional turnover was higher during the pre‐inundation phase, and this phase also showed greater limnological heterogeneity in comparison to the post‐inundation phase. We observed a strong seasonal dynamic in taxonomic turnover, with high turnover during the dry season. However, these seasonal dynamics disappeared after river damming. We demonstrated that the patterns of taxonomic and functional beta diversities were influenced by limnological variables and seasonal dynamics, which resulted in reduced variability in both species composition and functional characteristics after the implementation of the reservoir.4.This study emphasises the importance of variations in annual flow regimes in lotic ecosystems. We also showed an association between environmental heterogeneity patterns the high taxonomic and functional diversity of zooplankton communities. [ABSTRACT FROM AUTHOR]

The current study investigated the relationship between sediment grain sizes and macroinvertebrate distribution along the Isiukhu River, a tropical stream in western Kenya. Ten sites in total were selected from the upstream, midstream and downstream areas. Sampling of sediments and macroinvertebrates was carried out twice a month from March 2018 to March 2019. Sediment was characterised as polymodal and extremely poorly sorted at the upstream; trimodal and extremely poorly sorted in the midstream; and polymodal and extremely poorly sorted towards the downstream of the river. Upstream sediments were fine gravelly mud and very coarse gravelly mud, while downstream sediments were very coarse gravelly muddy very fine sand and very fine gravelly, clayey very fine sand, indicating sediments became finer downstream. The study identified 993 individual macroinvertebrates from 21 families. Highest mean abundance (100 ± 9.2) was recorded at Kimangeti (upstream) while least was at Mutono (11 ± 0.7) (downstream). A regression model of the relationship between mean sediment grain size and mean macroinvertebrate abundance indicated that sediment grain size accounted for 28.7% of the spatial variability of macroinvertebrate abundance. The connection between sediment size and macroinvertebrate abundance and diversity in the Isiukhu River highlights that control of soil erosion in this catchment is important for the ecology of this river. [ABSTRACT FROM AUTHOR]

Urban streams are impacted by multiple anthropogenic environmental stressors that exert considerable pressure on resident fish populations. Species such as brook trout (Salvelinus fontinalis) are particularly vulnerable because urban environments typically limit the cold oxygenated water required by all life stages. To understand factors associated with native brook trout movement in urban streams, we monitored 20 radio-tagged individuals from late summer through the spawning season in autumn, and modelled how movement was influenced by body size and habitat. Tracking occurred in two adjacent streams that differed in forest cover and channelization. In both streams, brook trout mainly travelled upstream, particularly at the onset of the autumn spawning season. Larger individuals exhibited greater movements, and habitat complexity imposed stronger effects in larger individuals. Greater movements were made into locations of shallower depth and lower conductivity, although these factors were conflated with movement into upstream locations. This study addresses a fundamental knowledge gap in urban stream ecology by providing detailed information on the movement of a key indicator species of aquatic ecosystem health. [ABSTRACT FROM AUTHOR]

When multiple species with similar trophic niches co-occur in an ecosystem, foraging, refuge, and breeding microhabitats are predicted to be partitioned in order to enable their coexistence. However, few studies have examined potential niche partitioning among vertebrates with a bi-phasic natural history, such as stream salamanders. In addition to microhabitat, the coexistence of multiple species and life-stages is likely facilitated by the partitioning of diet. As plethodontid stream salamanders have an aquatic larval stage and a semi-aquatic adult stage (i.e., post-metamorphic), the diets of multiple species and life-stages can elucidate patterns in their community structure. Specifically, dietary overlaps can be used to evaluate the level of niche overlap and thus, potential competition among different species and life-stages. In this study, we non-lethally examined the dietary overlap among five predacious aquatic larval and three semi-aquatic adult stream salamander species in southeastern Kentucky. Our data illustrated both inter- and intra-specific dietary overlaps among the stream salamander community. We additionally observed dietary overlaps among all adult salamanders and their larval counterparts. We found differential dietary clustering and separation among some of the species and life-stages. Though not directly tested in this study, our results are suggestive of selection/constraint to species- and life-stage-specific foraging microhabitats. [ABSTRACT FROM AUTHOR]

Ecological flow (E-flow) determination is an essential component of stream management and the preservation of aquatic ecosystems within a watershed. E-flow should be determined while considering the overall status of the watershed, including the hydrological cycle, hydraulic facility operation, and stream ecology. The purpose of this study is to determine E-flow by considering watershed status through coupled modeling with SWAT and PHABSIM. SWAT was calibrated to ensure reliability when coupling the two models, using observed data that included streamflow and dam inflows. The calibration result of SWAT showed that the averages of R2, NSE, and RMSE were 0.62, 0.57, and 1.68 mm/day, respectively, showing satisfactory results. Flow duration analysis using the SWAT results was performed to apply to discharge boundary conditions for PHABSIM. The averages of Q185 (mid-range flows) and Q275 (dry conditions) were suitable to simulate fish habitat. The habitat suitability index derived through a fish survey was applied to PHABSIM to estimate E-flow. E-flow was estimated at 20.0 m3/s using the coupled model and compared with the notified instream flow by the Ministry of Environment. The results demonstrate a high level of applicability for the coupled modeling approach between the watershed and physical habitat simulation models. Our attempt at coupled modeling can be utilized to determine E-flow considering the watershed status. [ABSTRACT FROM AUTHOR]

At present, most research on the optimal scheduling of hydropower stations in the day-ahead electricity market focuses on the optimal power generation benefit, which does not consider the ecological impact of the generated discharge flow on downstream rivers. To address this situation, the ecological impact of electricity markets on rivers downstream of annually regulated hydropower stations is studied, and adjustment methods for traditional scheduling methods are proposed to achieve better ecological benefits. To this end, a multitimescale nested forecasting scheduling model is proposed for simulating hydropower station scheduling. In addition, the ecological flow index of the distribution flow method, an easy-to-implement ecological indicator model, was used to quantify the ecological benefits of discharge flows. A hydropower station on the upper course of the Lancang River in China was used to analyze the electricity market's impact on downstream river ecology. The results show that under the optimal power generation benefit scheme, the ecological benefits are influenced not only by electricity price characteristics but also by multitimescale nested scheduling. Based on an analysis of these two factors, the general rules for the ecological benefits of rivers downstream of annually regulated hydropower stations in the day-ahead electricity market are summarized. In addition, the relationship between power generation and ecological benefits is analyzed for various schemes in a multiobjective scheduling problem framework. Finally, adjustment methods for traditional scheduling methods are proposed to achieve better ecological benefits. [ABSTRACT FROM AUTHOR]

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Scalar transport in vegetated flow plays an important role in natural river ecology. In this study, a scalar transport model for the flow with flexible submerged vegetation is developed. The turbulent structure and scalar transport characteristics in the flow without vegetation, and with rigid and flexible vegetation are compared. The results show that the scalar diffusion in the flow is mainly governed by the turbulent diffusion outside the diffusion boundary layer. The wake flow downstream of rigid vegetation and the small‐scale Kelvin–Helmholtz (KH) vortices near the top of the canopy are the main reasons to enhance the turbulence intensity in the flow and to significantly increase the turbulence diffusion of scalars. However, the flexible vegetation movement induces the large‐scale KH vortices near the top of the canopy. It also causes to increase the turbulence intensity in the flow, to redistribute the scalar concentration in a wide range, to increase the scalar concentration across the flow depth, and to increase the scalar turbulence diffusion intensity. In the flow with rigid vegetation, the values of the turbulent Schmidt number vary from 0.72 to 1.93 below the top of the canopy, while in the flow with flexible vegetation, they vary from 0.58 to 1.99 only near the top of the canopy. Above the top of the canopy, the Schmidt number ranges from 0.48 to 0.84. The results are useful for the parameterization of scalar transport in natural vegetated rivers. Key Points: A 3D numerical model simulating scalar transfer in water flow with flexible submerged vegetation is establishedThe turbulent diffusion caused by the Kelvin–Helmholtz instability is the main reason to enhance the scalar transferThe turbulent Schmidt number ranging approximately 1.0–2.0 near the canopy height, being larger than that above the canopy [ABSTRACT FROM AUTHOR]

River–floodplain ecosystems play a crucial role in connecting landscape patches through hydrological connectivity, but they are among the most threatened ecosystems. Floodplains provide important habitat for amphibians by connecting aquatic and terrestrial habitats. Modifications to floodplain hydrology can impact amphibian communities, yet few studies have examined amphibian metacommunities in floodplain wetlands.In this study, we assessed patterns in amphibian breeding abundance in one of the largest floodplains of the Danube River, Hungary, relative to hydrological connectivity and multi‐scale variables at 30 waterbody sites. Our aim was to determine whether these patterns aligned with the pond‐permanence gradient hypothesis, where breeding amphibian abundance is predicted to be highest in ephemeral ponds without large predatory fish. We used Bayesian hierarchical modelling to estimate multi‐species abundance from repeated survey (count) data collected over one breeding season.We detected the eggs and larvae of four amphibian species. The best model of abundance included covariates describing two principal component axes associated with waterbody hydrology and landscape composition within a 500‐m radius of a site. There was a positive relationship between mean community abundance at a site and hydrological disconnection from the main river channel; however, the common toad (Bufo bufo) was associated with hydrologically connected waterbodies. There was a positive relationship between mean community abundance and a high proportion of forest cover and low cover of agricultural land within a 500‐m radius around a site, although this relationship was clear for only two species. There was no support for models containing the number of large predatory fish species detected at a site.Although our results showed that amphibian abundance declined with hydrological connectivity, based on model selection we could not ascribe this relationship to an increased number of large predatory fish species detected in waterbodies close to the main river channel. Differences in life history and habitat requirements are likely to have explained interspecific responses to hydrological connectivity. Our results underscore the importance of addressing amphibian abundance at multiple spatial scales in floodplain wetlands, as landscape composition partly explained patterns in abundance.Application of multi‐species abundance modelling allowed us to investigate environmental relationships for common and infrequently detected species. Habitat restoration programmes in floodplains should provide waterbodies disconnected from main river channels as potential amphibian breeding sites and protect or restore forest as terrestrial habitat. [ABSTRACT FROM AUTHOR]

This article proposes to investigate delineations of the audience in podcasting in streaming media ecology. To meet this objective, we highlight the scales between contents, circulation, and consumption of podcasts in platformization contexts. We observe these relationships from an intersectional approach that involves spaces between codes, contents and software to understand the dynamics of interrelationships between contents and its flows which are associated with the emergence of varied audiences, derived from listening practices, characterized by binge listening; fidelity strategies; hybrid recommendation practices, playlists and cross-device consumption in multiplatform architecture. [ABSTRACT FROM AUTHOR]

Urban stream restoration is growing globally, but there is much to learn from successes, failures, and evaluating tradeoffs in restoration practices. Significant time and resources have been invested towards restoring the structure and function of urban ecosystems and understanding and slowing the drivers of degradation. However, the rapid pace of urbanization and its effects on urban waters present an ever-growing challenge to environmental managers and restoration practitioners when identifying and prioritizing effective strategies for restoration and monitoring outcomes. Here, we synthesize major findings and papers originating from the 5th Symposium on Urbanization and Stream Ecology (SUSE5) and propose a new concept for monitoring restoration based on lessons learned. Efforts from SUSE5 showed that urban disturbances and restoration activities have strong localized impacts that can be challenging to detect and disentangle across broader watershed scales and longitudinal flowpaths. Most urban stream restoration projects are monitored at only one or a few locations that do not capture significant variability across stream reaches and longer flowpaths. Based on knowledge from SUSE5, we present a new concept called 'restoration milestones.' The restoration milestones concept proposes that the scale of stream monitoring over space and time can influence whether a stream restoration project is considered a success or failure. Therefore, answers to questions regarding restoration effectiveness and durability can be affected by spatial and temporal monitoring scales. Setting realistic restoration milestones involves establishing monitoring strategies that account for spatial and temporal variability. Tracking restoration performance through time across stream reaches along longitudinal flowpaths could aid in more accurately assessing project performance. We explore applications for evaluating restoration milestones along longitudinal stream flowpaths including: (1) identifying target areas of improvement along drainage networks, (2) accurately accounting for tradeoffs in habitat, protection of infrastructure, and water quality along flowpaths, and (3) detecting how far downstream the effects of stream restoration and stormwater management can be propagated. Monitoring across different spatial and temporal scales is an overlooked but critical factor in determining restoration success. Additionally, the scale of the restoration project itself can determine the type and magnitude of improvements. Expectations for what a restoration project can accomplish in terms of water quality improvements should be calibrated to the project's spatial scale and evolution over time. Longitudinal studies of stream restoration help identify successes and failures along flowpaths. [ABSTRACT FROM AUTHOR]

Intermittent streams that cease to flow during dry periods represent more than half of the global river network, and are particularly common in arid and semi‐arid regions. They are characterised by high spatial and temporal variability in aquatic habitat, forming a shifting habitat mosaic that supports diverse assemblages of native and endemic species. Climate projections for much of the world predict greater variation in precipitation and increasing drought severity, suggesting a need to better understand species' responses to habitat variability within intermittent stream ecosystems. Here we explored changes in the distribution and abundance of aquatic vertebrates in response to a wide range of annual hydrologic conditions within a Mediterranean‐climate intermittent stream in California.We conducted wetted habitat and vertebrate abundance surveys during the dry season for 7 years, spanning both extreme wet and extreme dry annual precipitation conditions, and characterised the variation in the size, persistence, and spatial configuration of wetted habitats in relation to the observed abundance and composition of fishes, amphibians, and aquatic reptiles. We characterised the habitat mosaic using a k‐means clustering approach, and identified three habitat types with distinct size, persistence, and connectivity distributions.We found that some wetted habitat units persisted across all years, regardless of antecedent precipitation, whereas others dried in all but the wettest years. We determined that persistent pools, a subset of wetted habitats present in the stream, supported diverse assemblages of native species even during extreme dry conditions, while transient pools acted as important habitat for particular species and life stages, including a young‐of‐year minnow species. Linear mixed models indicated that species' abundances were influenced by habitat quantity, quality, and connectivity.Our study ‐ considers intermittent streams as shifting habitat mosaics and uses multi‐year surveys to understand the ecological consequences of habitat variability within and across years to advance our understanding of intermittent stream ecology and the implications of climate change for spatial and temporal patterns of refuge habitat. [ABSTRACT FROM AUTHOR]

In response to growing concern about the increased disconnect between youth and their outdoor environment, this study examines how nature-based citizen science experiences with a local animal (American eels) influence urban adolescents' (high-school students) sense of place in a US city. The juvenile American eel is a unique animal due to its see-through body, small size, lengthy migratory pathway, high periodic population density, and conservation concern. Interview, written, and observational data were collected through a case study of ten high-school students during a citizen science project that lasted three months. Analyses of these data indicate that students developed greater -ecological place meaning and place attachment. Students developed greater ecological place meaning by learning more about the ecology of the river and the eels, and developed greater place attachment by developing pride and empathy. Based on these findings, we argue that nature-based citizen science programs can help environmental educators in the US foster more equitable access to nature by providing urban youth with much-needed opportunities to deeply experience local places and develop a closer and more meaningful relationship with their local environment. [ABSTRACT FROM AUTHOR]