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Natural river landscapes can be biodiversity hotspots but are one of the most human altered ecosystems with habitats significantly damaged around the world, and a third of fish populations threatened with extinction. While riparian ecosystems have been negatively altered by anthropogenic activities, effective planning and restoration strategies can reverse negative impacts by improving habitat quality. However, restoring rivers requires appropriate data on current riparian health while also considering priorities for different stakeholders. To address this, a Geographic Information System (GIS) was used to create a new and transferable restoration priority model based on a section of the river Linth in Switzerland as a case study. The restoration priority model is founded on connectivity, river condition, national priority species and species hotspots. Landscape change of the riparian zone was analyzed using aerial imagery and landscape metrics. Almost a quarter of rivers within the study area were considered high or very high restoration priority, with many aquatic species set to benefit from restoration. From 1946 to 2019, the riparian landscape became highly fragmented due to significant growth in impervious surfaces and a concomitant loss of agricultural land. The GIS model provides a tool by which environmental agencies can manage natural features over large scales, while also planning priorities and targeting conservation strategies to the areas of greatest need. [ABSTRACT FROM AUTHOR]

Isotopic evidence of groundwater and stream water is frequently used to investigate water exchanges with groundwater. Monthly sampling of rain, stream water, and groundwater was conducted at Tims Branch watershed in South Carolina for the oxygen and hydrogen stable isotope (δ2H and δ18O) measurement, as well as pH and oxidation–reduction potential (ORP). Together with a mass balance perspective, it was determined that it takes a few weeks to one month for groundwater in the hyporheic zone to fully exchange with stream water. From hydrodynamic modelling, we show that substantial (up to 70 %) groundwater exchange occurs at gaining and losing sites. Groundwater exfiltration, i.e. inflow into stream water, contributes up to 4 % to stream water, with the remainder from upstream exfiltration. A 2–4 % per day renewal rate of adjacent groundwater would indirectly indicate a groundwater residence time in the order of half a month to a full month (assuming either a well-mixed case or large dispersion rate in pulse flow case), in agreement with a greatly reduced variability of δ2H and δ18O of groundwater compared to stream water and rain. This reduced variability of stable isotope signal from groundwater confirms our hypothesis that riparian groundwater mixing at Tims Branch is more of a mixed type rather than a pulse flow type. A monthly time scale is sufficient for groundwater to become anoxic at exit points into stream water resulting in the episodic production of natural organic matter- and iron-rich flocs upon oxidation. [ABSTRACT FROM AUTHOR]

ABSTRACT A new species of the tribe Malaxideae (Orchidaceae), Crepidium assamicum, is described and illustrated here as new species from Assam, North East India. The new taxon is superficially similar to Crepidium purpureum but differs in its habitat, plant size, long floral bract, very densely flowered inflorescences, leaf number, larger petiole size, both winged throughout and flower color. This species is confined to grow in open grassland near river bank of Dibru‐Soikhowa, Dibrugarh district of Assam, in a huge population comprising 500–600 individuals. The threat status of this new species is provisionally assessed here as “Threatened” following the IUCN Red List Categories and Criteria version 16 (2024). [ABSTRACT FROM AUTHOR]

The Qinling Mountains in China frequently experience geological disasters, with large‐scale landslides being particularly prominent, causing severe economic losses to the local area. To gain a comprehensive understanding of the geological disaters distribution in the region, we conducted extensive research on the entire Qinling Mountains, covering an area of approximately 380,000 km2. By employing methods such as literature review, data collection, and interpretation of remote sensing images, we have successfully created a database of landslides. The inventory of landslides includes a total of 169,888 large‐scale landslides, covering a combined area of approximately 1575 km2. The average size of these landslides is approximately 92,734 m2. The scale of these landslides varies widely, with the smallest individual landslide covering an area of 166.25 m2 and the largest reaching 12.9 km2. Upon examining areas with frequent landslides, it was observed that landslides are usually densely distributed along riverbanks or within valleys. Landslide development is also dense in areas prone to frequent historical earthquakes. This comprehensive database provides essential data to support the analysis of spatial distribution patterns of large‐scale landslides in the Qinling Mountains. It also facilitates landslide assessments and serves as a reference for the prevention and control of landslide disasters in the area. [ABSTRACT FROM AUTHOR]

River and lake health assessment (RLHA) is an important approach to alleviating the conflict between protecting river and lake ecosystems and fostering socioeconomic development, aiming for comprehensive protection, governance, and management. Vegetation, a key component of the riparian zone, supports and maintains river and lake health (RLH) by providing a range of ecological functions. While research on riparian zone vegetation is ongoing, these studies have not yet been synthesized from the perspective of integrating RLHA with the ecological functions of riparian zone vegetation. In this paper, based on the bibliometric method, the relevant literature studies on the topics of RLHA and unmanned aerial vehicle (UAV) remote sensing of vegetation were screened and counted, and the keywords were highlighted, respectively. Based on the connotation of RLH, this paper categorizes the indicators of RLHA into five aspects: water space: the critical area from the river and lake water body to the land in the riparian zone; water resources: the amount of water in the river and lake; water environment: the quality of water in the river and lake; water ecology:aquatic organisms in the river and lake; and water services:the function of ecosystem services in the river and lake. Based on these five aspects, this paper analyzes the key role of riparian zone vegetation in RLHA. In this paper, the key roles of riparian zone vegetation in RLHA are summarized as follows: stabilizing riverbanks, purifying water quality, regulating water temperature, providing food, replenishing groundwater, providing biological habitats, and beautifying human habitats. This paper analyzes the application of riparian zone vegetation ecological functions in RLH, summarizing the correlation between RLHA indicators and these ecological functions. Moreover, this paper analyzes the advantages of UAV remote sensing technology in the quantitative monitoring of riparian zone vegetation. This analysis is based on the high spatial and temporal resolution characteristics of UAV remote sensing technology and focuses on monitoring the ecological functions of riparian zone vegetation. On this basis, this paper summarizes the content and indicators of UAV quantitative remote sensing monitoring of riparian zone vegetation for RLHA. It covers several aspects: delineation of riparian zone extent, identification of vegetation types and distribution, the influence of vegetation on changes in the river floodplain, vegetation cover, plant diversity, and the impact of vegetation distribution on biological habitat. This paper summarizes the monitoring objects involved in monitoring riparian zones, riparian zone vegetation, river floodplains, and biological habitats, and summarizes the monitoring indicators for each category. Finally, this paper analyzes the challenges of UAV quantitative remote sensing for riparian zone vegetation at the current stage, including the limitations of UAV platforms and sensors, and the complexity of UAV remote sensing data information. This paper envisages the future application prospects of UAV quantitative remote sensing for riparian zone vegetation, including the development of hardware and software such as UAV platforms, sensors, and data technologies, as well as the development of integrated air-to-ground monitoring systems and the construction of UAV quantitative remote sensing platforms tailored to actual management applications. [ABSTRACT FROM AUTHOR]

Freshwater and terrestrial biodiversity are linked through spatial resource flows. Key examples are detrital subsidies from the riparian vegetation that form the base of food webs in small streams. Despite the central role of detritivores in these food webs, the consequences of altered riparian vegetation type and resource availability on their trophic strategies are less known.Therefore, we experimentally tested direct and indirect effects of riparian vegetation type (i.e. riparian forests present vs. absent) on trophic interactions and dietary imbalances of aquatic detritivores. To characterise trophic strategies, we used stoichiometric and isotopic differences between consumers and resources as functional measures of trophic link strength in leaf litter bags naturally colonised by stream decomposers and detritivores.Our results show that an absence of riparian forests affected stoichiometric and isotopic properties in stream detrital food webs. Where local riparian forests were absent, leaf litter showed lower C:N ratios, which only trichopteran detritivores mirrored, whereas plecopteran and crustacean detritivores showed differences in their isotopic signatures. Diverging patterns between resources and consumers could lead to a rewiring of energy flow paths and weaken the coupling between aquatic detritivores and terrestrial detritus.Consequently, our findings demonstrate that riparian forests are essential for aquatic food webs by not only influencing organisms themselves but also their trophic interactions and energy flow paths. Aquatic detritivores depending on terrestrial subsidies can be highly sensitive to local changes in their resource environment. Therefore, functionally divergent patterns between resources and consumers in recipient systems highlight how habitat properties of the donor system can affect food webs connected across ecosystem boundaries. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Several studies have indicated that tri-colored bats (Perimyotis subflavus) are extending their distributional range westward in the United States. Montane and subalpine habitats consist of a mosaic of forest types including Lodgepole Pine woodlands and meadows, which provide an opportunity to study how a newly arriving species—typically associated with lowland riparian systems—is adapting to novel environmental conditions. The objectives of this study are to document Tri-colored Bat activity in these novel habitats and to quantify which factors are influencing activity patterns in habitats and at elevations not previously documented. We surveyed sites in various stages of secondary succession following beetle kill outbreaks using acoustic monitoring and nonparametric multiplicative regression to model habitat activity patterns. Results showed that activity was highest in meadows and early time-since-kill (TSK) forests in the beginning of the survey period and activity increased in late TSK forest habitats at the end of the survey in early August. Tri-colored bats are not restricting their activity to lower-elevational riparian areas in the Colorado foothills but appear to also be using these high-elevation habitats. Careful consideration of misidentification confirms the high likelihood of tri-colored bats at our sites. We hope that this study will support conservation efforts considering the expected US Fish and Wildlife Service Endangered listing for this species. [ABSTRACT FROM AUTHOR]

Livestock grazing is a major economic activity worldwide. Cattle frequently graze and congregate in watercourses and riparian areas because of the availability of water, shade and the quality and variety of forage, thereby altering the ecological condition of stream ecosystems. We have explored the effects of cattle intrusion on the environmental conditions and fish assemblages of four neotropical prairie streams from Argentina's Pampas region. At each stream, both ungrazed and grazed conditions were surveyed. Water quality, habitat structure, riparian vegetation and fish assemblages were sampled. Significant detrimental changes were observed in environmental conditions of grazed sites in contrast to ungrazed sites. Fish assemblage structure and function were also significantly influenced by the environmental conditions imposed by cattle intrusion. Our results reveal the magnitude and direction of environmental changes imposed by cattle intrusion in prairie streams and highlight several key aspects of fish assemblages and populations that change accordingly. Relevant aspects for conservation and management purposes of these fragile ecosystems, such as protection of riparian vegetation condition and the control of cattle access and social engagement, are discussed. [ABSTRACT FROM AUTHOR]

Riverbank lines change over time, causing loss of land and property. Accurate mapping of riverbank lines is essential for restoration and preservation. This paper presents a method to map riverbank lines by combining georeferenced orthoimages and lidar digital elevation model (DEM). This method uses the properties that lidar can provide elevations under trees and open water edges are visible in orthoimages to extract the planimetric locations of bank lines. The orthoimage pixels with less than 0.15% slope on the DEM were replaced by water pixels. Principal component analysis (PCA) was conducted using DEM, slope, and orthoimage bands. Training data of river body and the background were identified manually on the first three component images. An alpha matting-based method was implemented using the training data to extract the bank lines. Bankline using a value of 50% probability were statistically and visually better when compared to the manual bank lines. [ABSTRACT FROM AUTHOR]

Flooding events tend to destroy the original flood-intolerant vegetation in riparian zones, but the flood-tolerant species can confront the stress, and contribute to the riparian ecosystem. Grass species, Hemarthria altissima , are usually dominant in the riparian zones. This species is considered as good forage which is usually grazed by livestock or mowed by local people. Therefore, the apical tissues of the plants are often removed, and the plants have to grow without stem apexes, during their life cycle. In this study, we aimed to examine the differences in growth performance of intact versus apex-cut individuals of H. altissima upon complete submergence. Two groups of H. altissima plants (with and without shoot apexes) were treated with dark non-submergence and dark complete submergence conditions for 200 days. During the experiment, we measured plant growth, biomass changes in plant organs, and the consumption of non-structural carbohydrates (NSC) by different tissues. During submergence, shoot elongation stopped, and around six lateral buds were developed averagely by each plant without apexes. This growth performance finally caused 60% decline of NSC in underground parts. The relatively intensive consumption of carbohydrates in submerged apex-removed plants induced the 21% stem length decreased under water, which indicated the decreasing submergence tolerance of plants with shoot apex removed. Therefore, we suggest that when using H. altissima for restoring degraded riparian ecosystems, the shoot apexes should be protected from grazing by livestock or harvesting by local people in order to maintain the submergence tolerance of H. altissima. [ABSTRACT FROM AUTHOR]

Understanding how landscape structure and riparian vegetation impact bee diversity is important for maintaining pollination service in urban areas. We explored spatial and temporal variation of bee communities across land use types in a riparian zone of a mountainous megacity in 2018 and 2022, examined whether riparian vegetation functions as corridors that maintain gene flow of bee populations, and mapped pollination supply at the landscape scale.Pielou index was higher in 2018 than in 2022, while no significant differences in abundance, Shannon and richness index were observed. The abundance of bees and the Shannon index were significantly and positively correlated with the abundance of flowers on grassland and forested land, respectively, while both were negatively correlated with the area of the building.The genetic differentiation of the bee communities in the riparian zone was lower than those outside, indicating the function of the riparian vegetation corridor. The pollination supply varied significantly between regions, with medium to high degree of pollination supply distributed primarily in residual habitats and the surrounding urban green spaces, while low degree in the remaining areas.Our results stress the importance of maintaining the continuity of vegetation in riparian zones and increasing flower abundance, especially native plant species, for the conservation of bees in urban areas. Read the free Plain Language Summary for this article on the Journal blog. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Under the influence of climate change and human activities, riparian ecosystems in arid regions are facing severe challenges such as extensive vegetation death. Meanwhile, conventional reservoir operation and vegetation irrigation have low water use efficiency and unsatisfactory vegetation restoration effect. For improving the efficiency of water resources regulation and protect riparian ecosystems in arid regions, this study proposes a multi-objective reservoir-gate ecological operation model coupled with vegetation priority irrigation. Firstly, based on ecological project layout and riparian vegetation types, ecological irrigation districts and ecological functional zones are divided for precise zoning water regulation, and then the irrigation order of "key protected zones > key restoration zones > ecological sensitive zones" and the water supply priority of irrigation districts are formulated for vegetation priority irrigation. Secondly, a long-term multi-objective reservoir-gate operation model coupled with vegetation priority irrigation is established, and an improved parallel approximate evaluation-based algorithm (RG-PAEM) is proposed for enhancing the search ability and calculation efficiency of optimization model. Finally, ecological operation effects under vegetation priority irrigation are analyzed through a case study of Tarim River basin in northwestern China. Results show that: (1) compared with conventional ecological irrigation, vegetation priority irrigation improves ecological and agricultural water supplies in Tarim River mainstream; (2) under vegetation priority irrigation, annual ecological water supplies of Level I to Level V irrigation districts account for 3%, 15%, 28%, 48%, and 6% of the total, respectively, and monthly ecological water supply reaches the maximum in July; (3) the upper and middle reaches of mainstream are important areas for riparian vegetation protection, the ecological water shortage decreased by 10% and 16% respectively through reservoir-gate ecological operation and vegetation priority irrigation. The study results provide theoretical and technical support for achieving scientific water resources regulation and sustaining desert riparian ecosystems. [ABSTRACT FROM AUTHOR]

Refinement of the governing equations for homogeneous isotropy in variable saturated porous media based on the basic equations for the seepage and temperature fields. Combined with the water exchange in the lateral hyporheic zone, a mathematical model of water and heat transport in the saturated-unsaturated zone of the lateral hyporheic zone of river-groundwater is established. The model was solved using COMSOL software and then validated by the measured data obtained from the test site. The simulation and validation results show that the model is effective in simulating the dynamics of hydrodynamic and temperature field changes in the river-groundwater lateral hyporheic zone under the conditions of water exchange, and that the mathematical model of hydrothermal transport can provide technical support for the in-depth study of hydrothermal exchange and pollutant migration processes in the riparian zone. [ABSTRACT FROM AUTHOR]

Efforts to create sustainable cities and urban climate-resilience depend on understanding how wildlife use the urban matrix to guide urban planning and design. Urban environments combine natural elements like topography and waterways, with various intensities of urban development. These combinations shape the spatial environment of cities and influence the diversity and persistence of urban wildlife. Insectivorous bats occur in urban areas, with urban tolerant species correlated with greater mobility and flexible roosting strategies, such as trawling bats. To understand how trawling bats use urban space, we studied patterns of land use selection in an urban population of a trawling bat, the large-footed myotis (Myotis macropus) in a subtropical city. We quantified fine-scale space use using radio telemetry over two seasons using land use categories applied in urban planning and design. Bats used urban land use types in a non-random manner, displaying a preference for green and blue space associated with the recreation land use type at both the landscape and home range scale. Tracked bats used waterways and riparian areas, as well as parkland, sportsgrounds and other green space adjacent to waterways. Trawling bats are dependent on riparian habitats, and these complex habitats are particularly vulnerable to changes to the availability of water resources associated with climate change. Maintaining spatial heterogeneity in urban planning and design by retaining and providing green space along, and adjacent to waterways, will provide a landscape mosaic for urban trawling bats to persist, facilitating climate change resilience in a specialist urban species. [ABSTRACT FROM AUTHOR]

The impacts of landscape patterns on river water quality are commonly acknowledged, but understanding the complex processes by which landscape patterns affect water quality is still limited, especially in densely populated urban areas. Exploring the mechanisms through which landscape characteristics influence water quality changes in urbanized rivers will benefit regional water resource protection and landscape-scale resource development and utilization. Utilizing daily water quality monitoring data from rivers in the urbanized area of the Pearl River Delta in 2020, our research employed canonical analysis and partial least squares structural equation modeling (PLS-SEM) to explore the processes and mechanisms of the influence of urbanized river landscape patterns on surface water quality. The results indicated that total nitrogen (TN) was the critical indicator limiting the water quality of rivers in the Pearl River Delta. The landscape composition and configuration indexes exhibited non-linear variations with scale, and the landscape fragmentation was higher closer to the river. Landscape patterns had the most significant influence on water quality under the characteristic scale of a 5.50 km circular buffer zone, and landscape composition dominated the change of water quality of urbanized rivers, among which 30.64% of the percentage patch area of construction (C_PLAND) contributed 46.40% to the explanation rate of water quality change, which was the key landscape index affecting water quality. Moreover, landscape patterns had a higher interpretive rate of 39.29% on water quality in the wet season compared to 36.62% in the dry season. Landscape composition had an indirect negative impact on water quality, with a value of 0.47, by affecting the processes of runoff and nutrient migration driven by human activities, while landscape configuration had an indirect negative impact on water quality, with a value of 0.11. Our research quantified the impacts of landscape patterns driven by human activities on surface water quality and proposed management measures to optimize the allocation of landscape resources in riparian zones of urbanized rivers. The results provide a scientific basis for water quality management and protection in urbanized rivers. [ABSTRACT FROM AUTHOR]

Populus euphratica is a unique constructive tree species within riparian desert areas that is essential for maintaining oasis ecosystem stability. The Tarim River Basin contains the most densely distributed population of P. euphratica forests in the world, and obtaining accurate distribution data in the mainstream of the Tarim River would provide important support for its protection and restoration. We propose a new method for automatically extracting P. euphratica using Sentinel-1 and 2 and Landsat-8 images based on the Google Earth Engine cloud platform and the random forest algorithm. A mask of the potential distribution area of P. euphratica was created based on prior knowledge to save computational resources. The NDVI (Normalized Difference Vegetation Index) time series was then reconstructed using the preferred filtering method to obtain phenological parameter features, and the random forest model was input by combining the phenological parameter, spectral index, textural, and backscattering features. An active learning method was employed to optimize the model and obtain the best model for extracting P. euphratica. Finally, the map of natural P. euphratica forests with a resolution of 10 m in the mainstream of the Tarim River was obtained. The overall accuracy, producer's accuracy, user's accuracy, kappa coefficient, and F1-score of the map were 0.96, 0.98, 0.95, 0.93, and 0.96, respectively. The comparison experiments showed that simultaneously adding backscattering and textural features improved the P. euphratica extraction accuracy, while textural features alone resulted in a poor extraction effect. The method developed in this study fully considered the prior and posteriori information and determined the feature set suitable for the P. euphratica identification task, which can be used to quickly obtain accurate large-area distribution data of P. euphratica. The method can also provide a reference for identifying other typical desert vegetation. [ABSTRACT FROM AUTHOR]

Summary Darwin's two opposing hypotheses, proposing that non‐native species closely or distantly related to native species are more likely to succeed, are known as ‘Darwin's Naturalization Conundrum’. Recently, invasion ecologists have sought to unravel these hypotheses. Studies that incorporate rich observational data in disturbed ecosystems that integrate phylogenetic and functional perspectives have potential to shed light on the conundrum. Using 313 invaded plant communities including 46 invasive plant species and 531 native plant species across the Three Gorges Reservoir Area in China, we aim to evaluate the coexistence mechanisms of invasive and native plants by integrating phylogenetic and functional dimensions at spatial and temporal scales. Our findings revealed that invasive plants tended to co‐occur more frequently with native plant species that were phylogenetically distant but functionally similar in the reservoir riparian zone. Furthermore, our study demonstrated that the filtering of flood‐dry‐flood cycles played a significant role in deepening functional similarities of native communities and invasive‐native species over time. Our study highlights the contrasting effects of phylogenetic relatedness and functional similarity between invasive and native species in highly flood‐disturbed habitats, providing new sights into Darwin's Naturalization Conundrum. [ABSTRACT FROM AUTHOR]

Pumas (Puma concolor) have a broad geographic range across the Americas and are globally listed as Least Concern. However, in Uruguay’s Pampas Grasslands, they are considered Data Deficient and regionally endangered in Argentina and Brazil. Understanding the distribution and population status of pumas is crucial for their conservation. This study examines puma occurrence in Uruguay’s Grasslands within a regional context, assessing habitat suitability and recent land use changes. Using a Species Distribution Model (SDM) in MaxEnt with 224 occurrence records (1999–2011) and bioclimatic and topographic predictors, we found intermediate habitat suitability in the Pampas Grasslands, indicating a naturally sparse puma population. The highest suitability was along riverbanks and riparian areas. Recent land use changes have transformed suitable habitats into areas less likely to support pumas, affecting a significant portion of Uruguay’s land. Our results suggest source-sink dynamics, where Uruguayan puma records likely represent dispersing individuals from established subpopulations in Eastern Argentina and Southern Brazil. [ABSTRACT FROM AUTHOR]

Plastic pollution in aquatic environments is a growing concern, with rivers recognized as major pathways. However, rivers themselves are also subject to pollution. Hence, understanding riverine plastic transport dynamics is essential for mitigating environmental impacts. Although plastic-related research focus has shifted from marine environments towards rivers, challenges remain in standardizing methods for monitoring and integrating spatiotemporal variabilities of riverine plastic occurrence into flux determination. This study addresses these challenges by adopting established methods from sediment research. Utilizing data from a net-based cross-sectional multi-point approach, it examines spatio-temporal and discharge-dependent variations. It comprehensively analyzes the complex dynamics of plastic transport in the Danube River, contrasting an impounded section near Aschach, Austria, with a free-flowing reach near Hainburg, Austria. The paper emphasizes the significance of applying these methodologies for accurate flux determination and underscores the risks of neglecting them. By incorporating average microplastic particle weights, we aim to overcome limitations in prior methodologies that solely emphasize qualitative aspects or rely on item numbers. Spatial distribution analysis revealed a pronounced stratification at low flow and a more variable distribution in the free-flowing section, attributed to higher turbulence. As discharge increased, vertical mixing occurred, along with distinct lateral patterns displaying increased concentrations toward the riverbanks. Encountering plastic particles throughout the river profile underscores their properties of both suspended and floating matter, emphasizing the importance of hydro-morphology and multi-point cross-sectional measurement approaches. Microplastic loads were calculated to be <6.9 t a-1 in Aschach and <17.1 t a-1 in Hainburg, compared to total plastic loads of <14.3 t a-1 in Aschach and <41.6 t a-1 in Hainburg. Consequently, plastic loads were doubled to tripled within the Austrian section of the Danube River. The study contributes valuable insights into the complex nature of plastic transport in river systems, emphasizing comprehensive spatial, temporal and discharge-dependent assessments for characterizing and managing plastic pollution. It suggests that rivers can function as sources, pathways and sinks of plastic pollution, contingent upon hydro-morphological conditions. This underscores the need for longitudinal, basin-wide assessments to accurately understand plastic transport dynamics. [ABSTRACT FROM AUTHOR]

Biological communities are structured by a variety of biotic and abiotic relationships, whose understanding forms the basis for effective conservation. Among the myriad factors influencing community dynamics, resource partitioning stands out, potentially enriching ecosystem complexity but also carrying risks for conservation if disregarded. In this study, we investigated intersexual and ontogenetic niche differences among populations of the West African softshell turtle Trionyx triunguis in Liberia, Cote d'Ivoire, Ghana and Nigeria. We observed that these distinct populations exhibited similar habitat preferences, favouring large rivers with abundant riverbank and aquatic vegetation, and muddy substrates. Disparities in habitat preferences were evident among populations and across various life stages, indicating the adaptability of the species. We found that the species was active throughout the year, but most of our sightings and captures occurred during the wet season. In light of the species' vulnerability to overhunting, our research findings provide important data on the ecology of this species that can assist in its effective conservation across all life stages. [ABSTRACT FROM AUTHOR]

Recent anthropogenic activities have escalated human exploitation of riparian zones of river ecosystems, consequently diminishing aquatic biodiversity. This intensification of land use is also causing water quality degradation and changes in water environmental factors, evidenced by increased nutrient levels and adversely impacting the community structure and diversity of aquatic organisms. Notably, the Weihe River Basin, the largest tributary of the Yellow River, has demonstrated signs of significant anthropogenic pressure. Despite this, comprehensive investigations examining the effects of land-use intensity on aquatic organism diversity in this watershed remain limited. In this study, the environmental impacts and macroinvertebrate diversity under high-intensity and low-intensity land-use scenarios within the Weihe River Basin were investigated through field surveys conducted during the spring and autumn seasons. Our results demonstrated that areas under high-intensity land use exhibited elevated nutrient concentrations (e.g., total nitrogen) compared to those under low-intensity land use. These environmental changes significantly influenced the macroinvertebrate community structure, reducing functional and phylogenetic diversities in high-intensity land-use watersheds. Hydrological factors (water depth, river width, and discharge) have a significant impact on macroinvertebrate taxonomic diversity. Thus, understanding the effects of land-use intensity on aquatic biodiversity is essential for ecological assessments of impacted watersheds and developing management strategies for the sustainable use and planning of riparian lands in the Weihe River Basin. [ABSTRACT FROM AUTHOR]

Dipcadi (Scilloideae: Asparagaceae) is a genus of bulbous monocots with approximately 40 species, of which 13 occur in India. Species delimitation within the genus has been troublesome hindering a comprehensive phylogenetic analysis. The most recent phylogeny of the subfamily Ornithogaloideae included six species of Dipcadi only from Africa. Here, we reconstructed the phylogeny of Ornithogaloideae including 23 accessions comprising 13 recognized taxa (11 species and two varieties) of Indian Dipcadi. The phylogenetic analyses were based on nucleotide sequences of three plastid regions (rbcL, matK and trnL-F spacer) and one nuclear region (ITS). Pseudogaltonia clavata exhibited sister relationship to Dipcadi. Our combined nuclear + plastid dataset analyses revealed a monophyletic Dipcadi with five clades, Clade I-V. Clade I, II and III included mainly Indian species whereas Clade V included mostly African species. Clade IV comprised D. serotinum. Clade I included nine taxa including our newly described species, D. mukaianum. The new species was phylogenetically placed with D. erythraeum, D. saxorum and D. ursulae. Morphologically, the species resembled D. montanum and D. ursulae but differed in characters such as tepal cohesion, number of ovules per locule and foul-smelling flowers. Clade II and III included 11 and six taxa, respectively. D. erythraeum which has a native range from Egypt to western India was found in Clades I and V. The widespread Dipcadi species, viz. D. erythraeum and D. serotinum showed polyphyly however, the monophyly of Dipcadi is established. Our studies suggest that additional molecular markers (plastid as well as nuclear) should be tested for their taxonomy utility. Further work on the historical biogeography of Dipcadi on the subfamily Ornithogaloideae with more genetic data will yield insights how aridification of the landscape would have shaped the evolution of the geographical clades. [ABSTRACT FROM AUTHOR]

The California Pipevine, Aristolochia californica Torr. is the only endemic California species within the cosmopolitan birthwort family Aristolochiaceae. It occurs as an understory vine in riparian and chaparral areas and in forest edges and windrows. The geographic range of this plant species almost entirely overlaps with that of its major specialized herbivore, the California Pipevine Swallowtail Butterfly Battus philenor hirsuta. While this species pair is a useful, ecologically well-understood system to study co-evolution, until recently, genomic resources for both have been lacking. Here, we report a new, chromosome-level assembly of A. californica as part of the California Conservation Genomics Project (CCGP). Following the sequencing and assembly strategy of the CCGP, we used Pacific Biosciences HiFi long reads and Hi-C chromatin proximity sequencing technology to produce a de novo assembled genome. Our genome assembly, the first for any species in the genus, contains 531 scaffolds spanning 661 megabase (Mb) pairs, with a contig N50 of 6.53 Mb, a scaffold N50 of 42.2 Mb, and BUSCO complete score of 98%. In combination with the recently published B. philenor hirsuta reference genome assembly, the A. californica reference genome assembly will be a powerful tool for studying co-evolution in a rapidly changing California landscape. [ABSTRACT FROM AUTHOR]

Conservation decisions are often based on population models that rely on underlying assumptions made about species' demographic parameters. The Rio Grande Cooter (Pseudemys gorzugi) is a conservation-dependent riverine turtle, but our understanding of its population dynamics has been limited due to the absence of long-term surveys. We used mark-recapture data collected between 2016 and 2022 from the Black River, New Mexico, USA, to evaluate P. gorzugi somatic growth parameters. Females reached larger maximum size than males but exhibited a slower growth rate. We observed only a slight difference in maximum length and Brody growth coefficient of turtles from different locations, but the growth coefficients were overall significantly lower than any other Pseudemys species. Turtles on the Black River represent the northernmost robust population of P. gorzugi. In light of the intense human use of the river and riparian areas coupled with the impacts of climate change, it is imperative to maintain commitment to conservation efforts to resist population declines given the slow somatic growth rate of the population. [ABSTRACT FROM AUTHOR]

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The Gandak River originates in Nepal and merges with the Ganga River in India. The Gandak River is experiencing significant geomorphological alterations due to climate change and anthropogenic causes. In this study, an attempt has done to examine river bank erosion & accretion, shifting of the river bank, sinuosity, and braiding index of the Gandak River between Sahibganj and the confluence with the Ganga River, covering a length of 92.4 km from 1989 to 2022 (33 years) using remote sensing and geospatial technologies. The delineation of the river bank line for different periods, along with the quantification of erosion and accretion of the river's right and left banks, were analysed using GIS, including the sinuosity and braiding patterns. The overall sinuosity value ranged from 1.16 to 1.01 and did not follow any specific pattern in significant reaches. The sinuosity value was almost constant over the most d/s reach of 30.74 km. The braiding index of the River was found to be the maximum between Ismailpur and Baijalpur and the minimum value between Munja and Chakia in 2015 and 1995 respectively. This study revealed that the river is shifting to the right, and bank protection measures were needed. Finally, the proposed investigation revealed the braiding phenomenon, river shifting in the transverse direction, and shifting of the meander bend was primarily responsible for the erosion and accretion of the river banks. This study will benefit local government agencies, concerned authorities, and people residing along the banks of the Gandak River by providing insights into the river's migration patterns. Further, this knowledge aids in better planning of riverbank protection measures and developing a navigation system. [ABSTRACT FROM AUTHOR]

River bank protection is vital in hydraulic river engineering to preserve natural rivers, lands, and critical constructions such as bridges. Spur dikes are erosion-protective structures that protrude outward from the river bank in different orientations to deflect the flow away from the riverbank. The present experimental study provides insight into the temporal variation in bed morphology and scours around rectangular-shaped spur dikes with different orientations, such as 60º, 90º, and 120º. Also, maximum scour depth (MSD) is developed compared to the condition when downward seepage is applied. The experiments examined the suitability of various spur dike orientation configurations and the scour development over time, specifically at intervals of 2, 12, and 24 hours, and compared with 24 hours (Seepage). Results showed that the orientation angle of 90º generated the highest scour depth, while the least scour depth was found with an orientation angle of 120º. The downward seepage intensifies the motion of sediment particles and leads to an escalated particle detachment, resulting in deeper scour depressions. The development of scour depth is initiated from the spur dike tip and reaches its maximum there. The deposition of sand particles shifted downstream, and a dune-like structure formed near the second spur dike. [ABSTRACT FROM AUTHOR]

Habitat suitability modeling is a commonly used methodology to plan and assess in‐stream habitat enhancement in rivers, such as for the key fish life stages spawning and juvenile development. However, their use only allows modeling the spatial distribution of habitats, but not their connectivity. By integrating micro‐scale habitat modeling and a larval drift model, we assess the functional connectivity between spawning and larval nursery habitats for four rheophilic and litophilic fish species in a channelized and hydropower impacted reach of the lower Inn River (Bavaria, Germany), in which two restoration measures, a bypass channel and an island side‐channel system, have been constructed to improve longitudinal connectivity and habitat conditions. The study aims to (a) map spawning and larval nursery habitats, (b) quantify their connectivity, and (c) optimize functional habitat connectivity through an alternative bypass channel location. Results show that the channel's morphological complexity influences quantity and quality of available spawning and nursery habitats and their connectivity. Despite the presence of nursery habitats across the analyzed channel, the slow lateral larval dispersion during drift limits their accessibility to only the left river bank, making only 33% of available habitats useable. The degree of functional connectivity and hence the percentage of useable habitats can however be increased up to 95.3 % when considering different spatial configurations of habitats, which were explored in two alternative restoration scenarios. The results demonstrate the importance of considering functional habitat connectivity in habitat assessments and restoration planning. Key Points: Spawning to nursery functional habitat connectivity was quantified using a larval drift modelMorphological complexity affects habitat availability and functional connectivityConnectivity can be improved by optimizing spatial distribution of spawning sites [ABSTRACT FROM AUTHOR]

We conducted a multi-scaled Ecoregional Conservation Assessment for the Southern Rockies (~14.5 M ha) and its trailing edge, the Santa Fe Subregion (~2.2 M ha), from Wyoming to New Mexico, USA. We included a representation analysis of Existing Vegetation Types (EVTs), mature and old-growth forests (MOG), and four focal species—Canada lynx (Lynx canadensis), North American wolverine (Gulo gulo luscus), Mexican spotted owl (Strix occidentalis lucida), and northern goshawk (Accipiter gentilis)—in relation to 30 × 30 and 50 × 50 conservation targets. To integrate conservation targets with wildfire risk reduction to the built environment and climate change planning, we overlaid the location of wildfires and forest treatments in relation to the Wildland–Urban Interface (WUI) and included downscaled climate projections for a lower (RCP4.5) and higher (RCP8.5) emission scenario. Protected areas were highly skewed toward upper-elevation EVTs (most were >50% protected), underrepresented forest types (<30% protected), especially MOG (<22% protected) and riparian areas (~14% protected), and poorly represented habitats (<30%) for at least three of the focal species, especially in the subregion where nearly all the targets underperformed compared to the ecoregion. Most (>73%) forest-thinning treatments over the past decade were >1 km from delineated WUI areas, well beyond the distance at which vegetation management can effectively reduce structure ignition risk (<50 m from structures). Extreme heat, drought, snowpack reductions, altered timing of peak stream flows, increasing wildfires, and potential shifts in the climate, favoring woodlands over conifer forests, may impact forest-dependent species, while declining snowpack may impact wolverines that den at upper elevations. Strategically targeting the built environment for fuel treatments would improve wildfire risk reduction and may allow for expansion of protected areas held up in controversy. Stepped-up protection for roadless areas, adoption of wilderness proposals, and greater protection for MOG and riparian forests are critical for meeting representation targets. [ABSTRACT FROM AUTHOR]

Sediment deposition is critical in maintaining riparian plant communities by providing essential nutrients and posing growth challenges. This study focuses on Cynodon dactylon, a dominant clonal species in the riparian zones of the Three Gorges Reservoir, and its interaction with sediment deposition over three years. Results indicated an average sediment deposition depth of 2.85 cm in the lower riparian regions. Observations revealed that C. dactylon coverage increased progressively at lower elevations despite its dominance diminishing with rising elevation levels. Additionally, positive linear correlations between C. dactylon coverage and sediment deposition depths were identified during flood periods, underscoring the species' role in enhancing sediment deposition. These findings suggest that C. dactylon plays a significant role in sediment accumulation, which may bolster its growth and survival prospects during subsequent growing cycles. The study highlights the importance of riparian vegetation, mainly perennial clonal species like C. dactylon, in promoting sediment accumulation and contributing to the stability and functionality of riparian ecosystems. [ABSTRACT FROM AUTHOR]

Floodplains have a high diversity of aquatic environments, including temporary lakes that constantly suffer from drought events. To survive in these conditions, several groups of organisms, among them ciliate protists, have developed strategies to avoid dehydration, such as resistance cysts. Sediment samples were collected from the central region of the lake during a drought event. The sediments were dried in an oven and stored. For the experiment, the sediment was rehydrated with water and kept in an incubation chamber. Samples from 6 microcosms were taken every seven days for 9 weeks. The frequency of each ciliate species hatching from resting structures was calculated using the constancy index, with morphospecies classified as constant, accessory, or rare. A total of 82 ciliates morphospecies were recorded, of which four were constant, three accessory, and 75 rare. The Oxytrichidae and Euplotidae families showed the highest morphospecies richness, among which only 16 morphospecies were already recorded in the literature as producing cysts. Although no significant temporal difference was observed for the difference in the hatching of morphospecies over time. The morphospecies increment curve showed an increasing trend during the experiment. Finally, based on predicted climate change projections, temporary environments may experience longer and more frequent periods of drought, thus ciliate morphospecies that are able to remain in a form of resistance for a long period will outperform those that are more sensitive or lack this type of functional trait. [ABSTRACT FROM AUTHOR]

Plastic production on a commercial scale began in the 1950s, reaching an annual production of 460 million metric tons in 2019. The global release of 22% of produced plastics into the environment has raised concerns about their potential environmental impacts, particularly on aquatic ecosystems. Here, we quantify and categorize plastic debris found along Richland Creek, a small, heavily forested watershed in western North Carolina, USA. Plastics within the riparian zone of seven 50 m reaches of Richland Creek and its tributaries were sampled two or three times. The 1737 pieces of collected plastic debris were returned to the lab where they were measured and categorized. A small-scale laboratory study using seven of the items collected was performed to determine their ability to break down into microplastics (particles < 5 mm in size). The majority (76%) of collected items were made of either plastic film (particularly bags and food wrappers, 43%) or hard plastics (e.g., bottles, 2%). However, when viewed on a surface area basis, films and synthetic fabrics (e.g., clothing, sleeping bags) equally dominated. Roughly three-quarters of the items collected had a width less than 10 cm, due primarily to the fragmentation of the original items; over two-thirds of the collected items were fragmented. Items composed of foams and films exhibited the highest fragmentation rates, 93% and 86%, respectively. Most collected plastics were domestic in nature, and the number of items increased downstream through more developed areas. Laboratory studies showed that plastic debris has a propensity to break down into microplastics. We believe the data collected here should be replicated in other streams, as these freshwater environments are the source of plastics that eventually enter the oceans. [ABSTRACT FROM AUTHOR]

River bank erosion is a serious problem in the riparian inhabitants of the alluvial plain. The study attempts to develop an integrated vulnerability index for bank erosion in the lower Ganga basin of India, employing a socio-spatial approach. The methodology for the assessment of the vulnerability index is comprised of three dimensions such as exposure, sensitivity and capacity which include 34 indicators covering social, economic, physical and environmental dimensions. A comprehensive survey encompassing 600 households across 30 villages was conducted to gather socio-economic indicators. These indicators include exposure, sensitivity, and capacity data for each village, which were aggregated to formulate an integrated vulnerability index. Subsequently, this index was exported to a geographic information system for the visualization of spatial patterns. The result shows that more than 60% of the villages are highly exposed to river bank erosion in the study area whereas 66.6% of villages have a high to very high sensitivity level and 50% have a low capacity index. The result also revealed that the east bank of the river is more vulnerable to river bank erosion in terms of vulnerability as compared to the west bank. This comprehensive methodology yields valuable insights into vulnerability to river bank erosion, providing decision-makers with essential tools for effectively managing disaster risk. [ABSTRACT FROM AUTHOR]

Traditional discharge monitoring usually relies on measuring flow velocity and cross-section area with various velocimeters or remote-sensing approaches. However, the topography of mountain streams in remote sites largely hinders the applicability of velocity–area methods. Here, we present a method to continuously monitor mountain stream discharge using a low-cost commercial camera and deep learning algorithm. A procedure of automated image categorization and discharge classification was developed to extract information on flow patterns and volumes from high-frequency red–green–blue (RGB) images with deep convolutional neural networks (CNNs). The method was tested at a small, steep, natural stream reach in southern China. Reference discharge data were acquired from a V-shaped weir and ultrasonic flowmeter installed a few meters downstream of the camera system. Results show that the discharge-relevant stream features implicitly embedded in RGB information can be effectively recognized and retrieved by CNN to achieve satisfactory performance in discharge measurement. Coupling between CNNs and traditional machine learning models (e.g., support vector machine and random forest) can potentially synthesize individual models' diverse merits and improve generalization performance. Besides, proper image pre-processing and categorization are critical for enhancing the robustness and applicability of the method under environmental disturbances (e.g., weather and vegetation on river banks). Our study highlights the usefulness of deep learning in analyzing complex flow images and tracking flow changes over time, which provides a reliable and flexible alternative apparatus for continuous discharge monitoring of rocky mountain streams. [ABSTRACT FROM AUTHOR]

We conducted a phytosociological survey of pioneer shrub and shrub-wood (brushwood) communities on river banks at the contact of gravel bars and rockfall, slope debris or colluvium in the spring area of the Nadiža River, in the gorge of the Soča River between Srpenica and Kobarid (Log Čezsoški and Magozd), in the Tolminka valley, and in certain other locations in the hills of western Slovenia. We identified a successional sequence of two grey willow and hop hornbeam communities, which we classify into the associations Salicetum eleagno-appendiculatae (Salicion eleagno-daphnoidis) and Peucedano verticillari-Ostryetum carpinifoliae (Fraxino orni-Ostryion). Both are indicators of natural river banks that have not been artificially stabilized. We expanded the knowledge of hop hornbeam communities in the pre-Alpine–northern-Dinaric part of Slovenia with a description of a new association Scopolio carniolicae-Ostryetum carpinifoliae. Its sites are characterised by slightly moist soil, and its stands by a higher proportion of species of the alliance Tilio-Acerion. [ABSTRACT FROM AUTHOR]

Viruses play a crucial role in regulating prokaryotic populations, yet their impact on subsurface environments, specifically groundwater habitats, remains poorly understood. In this study, we employed the virus-dilution approach to measure lytic virus production rates in shallow groundwater located near the city of Vienna (Austria) during the period from July−November 2020. Physico-chemical parameters (pH, electrical conductivity, water temperature, concentration of dissolved oxygen), prokaryotic, and viral abundance, and viral decay rates were monitored as well. Our findings revealed low virus-to-prokaryote ratios varying between 0.9−3.9 throughout the study period and a lack of correlation between prokaryotic and viral abundance in groundwater. Virus production rates varied between 9−12% of viral abundance h-1 in July−August and between 34−36% of viral abundance h-1 in October−November. Seasonal variations in virus production rates were found to be correlated with electrical conductivity, revealing ~3.5 times higher virus production rates during periods with high electrical conductivity and low groundwater recharge in October−November compared to July−August with higher groundwater recharge and lower electrical conductivity. Our data indicate that groundwater recharge disrupts the balance between virus and prokaryotic host communities, resulting in a deficiency of suitable prokaryotic host cells for viral proliferation. [ABSTRACT FROM AUTHOR]

The decline of swallowtail butterflies in forest habitats, which was not a significant concern about two decades ago, has now garnered attention worldwide, leading to their designation as globally endangered by the International Union for Conservation of Nature. A recent study conducted in the north bank landscape (NBL) of river Brahmaputra, specifically under the Bodoland Territorial Region in India, has shed light on the remarkable diversity of swallowtail butterfly species in the area. The study documented a total of 35 species representing eight different genera. Notably, three species are endemic to northeastern India, and 12 enjoy federal protection. The findings suggest that the studied landscape plays a crucial role in supporting larval host plants and adult resources of swallowtail butterflies along with the other abiotic factors. These butterflies depend on 25 plant species from six families as essential food sources. Unfortunately, these host plants, valued for their traditional medicinal properties, are being overexploited. Urgent conservation measures are imperative to safeguard the habitats of swallowtail butterflies and other wildlife in the NBL under Bodoland Territorial Region, as they face significant threats from practices such as agriculture, illegal tree felling, forest fires, and cattle farming. [ABSTRACT FROM AUTHOR]

Bank filtration supports the growing global demand for drinking water amidst concerns over organic micropollutants (OMPs). Efforts to investigate, regulate and manage OMPs have intensified due to their documented impacts on ecosystems and human health. Non-targeted analysis (NTA) is critical for addressing the challenge of numerous OMPs. While identification in NTA typically prioritises compounds based on properties like toxicity, considering substance quantity, occurrence frequency and exposure duration is essential for comprehensive risk management. A prioritisation scheme, drawing from intensive sampling and NTA of bank filtrate, is presented and reveals significant variability in OMP occurrence. Quasi-omnipresent substances, though only 7% of compounds, accounted for 44% of cumulative detections. Moderately common substances, constituting 31% of compounds, accounted for 50% of cumulative detections. Rare compounds, comprising 61%, contributed only 6% to cumulative detections. The application of suspect screening for 31 substances to the dataset yielded results akin to NTA, underscoring NTA's value. Correlation between both methods demonstrates the efficacy of high-resolution mass spectrometry-based NTA in assessing temporal and quantitative OMP dynamics. [ABSTRACT FROM AUTHOR]

In order to explore the sediment deposition characteristic of ecological riverbanks associated with vegetation restoration in the deep waterway regulation scheme of Yangtze River, two kinds of typical ecological riverbanks and a traditional riprap riverbank (TRR) in engineering areas were investigated. The vegetation community characteristics, sediment aggregate compositions, nutrient contents, total organic carbon (TOC), sediment microbial biomass carbon (MBC), sediment microbial biomass nitrogen (MBN), and sediment microbial biomass phosphorus (MBP) were determined. The results indicated that the ecological restoration effect of the lattice gabion ballasted vegetation mat riverbank (LGBVR) was best, followed by the mesh grid riverbank (MGR), and that of the TRR was relatively poor. In different ecological riverbanks, the sediment aggregated compositions were not significantly varied. The sediment contents of NH4+-N, available phosphorus (AP), and TOC in ecological riverbank areas were relatively higher than those of the TRR. In the LGBVR, the sediment contents of MBC were relatively higher than those of the others. The sediment deposition characteristics and ecological restoration effects in the study area should be monitored for a long time. [ABSTRACT FROM AUTHOR]

Carbon (C), nitrogen (N), and phosphorus (P) are essential nutrients that promote plant growth and development and maintain the stability of ecosystem structure and function. Analyzing the C, N, and P characteristics of plant leaves aids in understanding the plant's nutrient status and nutrient limitation. Seasonal water‐level fluctuations in riparian zones lead to various ecological problems, such as reduced biodiversity and decreased ecosystem stability. Therefore, comprehending the stoichiometric characteristics of riparian zone plants and their nutrient response to plant traits is important for a deeper insight into riparian zone forest ecosystems. This study analyzed the C, N, and P contents of the leaves of 44 woody plants in the riparian zone of the Dahuofang Reservoir to investigate the stoichiometric characteristics of C, N, and P of trees in the region. The results showed that the average C content of the leaves in woody plants was 446.9 g kg−1; the average N content was 28.42 g kg−1; and the average P content was 2.26 g kg−1. Compared to global and regional scales, woody plants in the riparian zone of the Dahuofang Reservoir exhibited higher N and P contents but lower N:P ratios. Compared to other riparian zones, woody plant leaves in the riparian zone of Dahuofang Reservoir had relatively high N content and N:P ratios. Variations in plant stoichiometric characteristics across different life forms were minimal, with only tree leaf P content significantly lower than its in shrubs. There was no significant correlation between leaf C, N, and P in woody plants, while specific leaf area showed a negative correlation with leaf C content. Trees in the riparian zone have high leaf N and P content and are primarily N‐limited during the growing season. This study reveals the stoichiometric characteristics of leaves of woody plants in the riparian zone, which can contribute to an in‐depth understanding of leaf stoichiometric patterns and the factors influencing them among plant life types in the riparian zone. [ABSTRACT FROM AUTHOR]

A new species, Macheriobia muriniensis Melo, Cunha & Santos sp. nov. (Diptera, Cecidomyiidae), is described here, inducing globoid galls on leaves of Machaerium lunatum in a Floodplain Forest along the banks of the Paricatuba River, Benevides, Pará, Brazil. Illustrations of the larvae, pupae, and adults (male and female), as a diagnosis for the species are provided. Specimens of Eurytomidae and Eulophidae were found associated with this gall midge.http://zoobank.org/urna:lsid:zoobank.org:pub:FEB646A4-49DE-4A9C-ADD3-D809DFBE563A [ABSTRACT FROM AUTHOR]

In floodplains, which are highly modified and less inundated, trees are expanding, thus raising concerns regarding their impact on freshwater organisms. We analyzed the relationship between forest expansion and the change in Odonata (dragonflies and damselflies) assemblage over an extended period of time in the floodplain with ponds of the Kiso River, central Japan. In the 1970s, the ponds were mainly surrounded by grasslands, and approximately 80% of Odonata species were non-forest species. However, the number of forest species increased and that of non-forest species largely decreased with the forest expansion over the past five decades, resulting in almost a similar number of forest and non-forest species in 2021. Whereas the abundance of the non-forest species had been greater than that of the forest species until the 2000s, the difference has been much smaller in the 2010s, and the non-forest species occupied approximately only 30% of the number of individuals in 2021. The forest expansion may have reduced the open-lentic habitats for the non-forest species, which require riparian grasslands for resting, foraging, and reproduction, and may disturb the immigration of non-forest species from the adjacent rice paddy fields and rivers. The development of canopy cover over the waterbodies may have decreased the light and temperature above and within the ponds, which might have caused a decline in species that prefer warm and open-water environments. Maintaining shifting-mosaic patterns of vegetation around the floodplain waterbodies through active management may be effective in conserving floodplain Odonata communities, including both forest and non-forest species. [ABSTRACT FROM AUTHOR]

Rockfill columns, also known as stone columns, were installed in a riverbank for slope stabilization measures. The goal of this fieldwork was to prevent slope instability of the riverbank while protecting an in-service aqueduct buried in the riverbank. At this site, rockfill columns were installed with the aid of steel casings (sleeves), which were later removed with a vibrodriver. Peak particle velocities were determined at select locations to monitor the ground vibrations during installation of rockfill columns and during extraction of the steel casings. Instrumentation and monitoring were implemented because there was uncertainty about the potential for structural damage to the nearby aqueduct due to ground vibrations during the stabilization works. In this case study, numerical modeling, calibrated versus field measurements in the ground and on the aqueduct, was used to simulate the ground vibrations due to the installation of three rockfill columns close to the aqueduct. Once calibrated, the numerical models were used to evaluate the effects of vibrations in terms of particle velocities in the ground, displacements of the aqueduct, and frequency spectra on the aqueduct walls. The numerical results showed that the highest particle velocities on the aqueduct were from the rockfill columns that had the steel casings located in the same soil layer as the aqueduct. Based solely on the response in terms of particle velocity, damage to the aqueduct is unlikely. However, the numerical results also showed that the aqueduct moves slightly, both vertically and laterally due to the vibration generated while removing the steel casings; and the frequency range of the waves in the ground are within the natural frequency of the soil, which could impose additional movement to the aqueduct if allowed to move freely with the soil. Numerical results and field data also show that even pulling the steel casings without vibration generated propagation of waves in the ground. [ABSTRACT FROM AUTHOR]

Riparian ecosystems are under a serious threat of invasion due to the clearance of riparian vegetation, which allows for increased light levels at ground level. This study presents the interactions between native Alternanthera sessilis (L.) R. Br. ex DC and invasive Alternanthera philoxeroides (Mart.) Griseb. during the colonization stage along a light gradient under tropical climate conditions. We conducted a 6 week growth experiment with monocultures of A. philoxeroides and A.sessilis and mixed communities of two species under four light levels (100%, 46%, 26% and 14% of full sunlight). Exposure to full sunlight (nearly 1800 μmol m−2 s−1) resulted in a significantly high biomass accrual in both species. However, biomass accrual did not correlate with the light intensity. At higher shade levels, reduction of lateral spread and shoot/root ratio was observed. Community composition had no influence on biomass accrual or morphological variations. Plasticity index values were approximately same in both species. Total relative yield was approximately two in all shade conditions, indicating that the two species interact neutrally along the light gradient. Therefore, the results of the study indicate that increased light levels will accelerate the proliferation of both species in riparian zones. Nevertheless, increased or decreased shade is unlikely to alter neutral interactions between A. philoxeroides and A. sessilis. [ABSTRACT FROM AUTHOR]