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Lumajang is one of the regency in East Java Province that has various types of freshwater ecosystems and have great potential as habitats for various insects, especially dragonflies. Dragonflies are insects that mostly live aquatically, so their existence is highly dependent on the condition of aquatic ecosystems. This study aims to compare the composition and diversity of dragonfly species in various habitat types in Lumajang. The study was conducted in lentic and lotic ecosystems in Lumajang. The method used was the Visual Encounter Survey (VES) technique adapted from the sweeping net. The data analysis used to determine differences in dragonfly species composition was the Bray-Curtis similarity analysis, while diversity analysis was conducted using the Shannon-Wiener index. This study recorded 29 species from seven families, including seven endemic dragonfly species found only on several islands in Indonesia. In the analysis of the Shannon-Wiener diversity index, the results show that in all research locations have a value of H'= 1.07-2.11, where the Rice Field habitat is the location with the highest value among other locations, with a value of H' = 2.11. The similarity analysis of dragonfly species composition using Bray Curtis similarity showed that it was divided into three groups. The composition of dragonflies found in several habitats in Lumajang is different, which can be influenced by many factors such as site elevation, habitat type (lentic or lotic), and habitat condition, as well as several other factors such as microclimate and vegetation (related to food availability). [ABSTRACT FROM AUTHOR]

The decline in water conditions contributes to the crisis in clean water biodiversity. The interactions between water conditions indicators and the correlations among these variables and taxonomic groupings are intricate in their impact on biodiversity. However, since there are just a few kinds of Internet of Things (IoT) that are accessible to purchase, many chemical and biological measurements still need laboratory studies. The newest progress in Deep Learning and the IoT allows for the use of this method in the real-time surveillance of water quality, therefore contributing to preserving biodiversity. This paper presents a thorough examination of the scientific literature about the water quality factors that have a significant influence on the variety of freshwater ecosystems. It selected the ten most crucial water quality criteria. The connections between the quantifiable and valuable aspects of the IoT are assessed using a Generalized Regression-based Neural Networks (G-RNN) framework and a multi-variational polynomial regression framework. These models depend on historical data from the monitoring of water quality. The projected findings in an urbanized river were validated using a combination of traditional field water testing, in-lab studies, and the created IoT-depend water condition management system. The G-RNN effectively differentiates abnormal increases in variables from typical scenarios. The assessment coefficients for the system for degree 8 are as follows: 0.87, 0.73, 0.89, and 0.79 for N-O3-N, BO-D5, P-O4, and N-H3-N. The suggested methods and prototypes were verified against laboratory findings to assess their efficacy and effectiveness. The general efficacy was deemed suitable, with most forecasting mistakes smaller than 0.3 mg/L. This validation offers valuable insights into IoT methods' usage in pollutants released observation and additional water quality regulating usage, specifically for freshwater biodiversity preservation. [ABSTRACT FROM AUTHOR]

Filamentous algae blooms (FABs) have been increasing globally in recent years, and their presence can have both harmful and beneficial effects on aquatic ecosystems. As one of the most common FABs, Cladophora blooms have been reported in the lakes of the Qinghai-Tibet Plateau during the past few years. However, there have been few studies focused on how FABs impact other aquatic organisms, especially in alpine lakes since these are at the forefront of responding to global climate change. In this study, the phytoplankton communities in different regions of Qinghai Lake were profiled in different seasons using meta-barcode sequencing. The phytoplankton assemblages in areas with Cladophora blooms were compared to those without Cladophora. The phytoplankton community structure correlated with physicochemical properties including water temperature, electrical conductivity, nitrate, and the presence or absence of Cladophora blooms. The relative abundance of Bacillariophytes was found to be higher in zones with Cladophora blooms than in other regions. Significant seasonal changes in phytoplankton biomass and β diversity were observed in zones with Cladophora blooms. Growth and microbial degradation of Cladophora can change the pH, dissolved oxygen, secchi depth, and nitrate. Together with seasonal temperature and electrical conductivity changes, Cladophora growth can significantly impact the phytoplankton biomass, community dissimilarity and assembly process. These results showed that Cladophora plays a key role in littoral aquatic ecosystem ecology. [ABSTRACT FROM AUTHOR]

This document is a summary of a special issue on "Taxonomy, Biodiversity, and Ecology of Parasites of Aquatic Organisms." The special issue focuses on the challenges faced by parasitologists in assessing the biodiversity of parasite species and understanding their distribution and ecological roles. The issue includes seven research articles that use integrative approaches, combining morphological, ecological, and molecular evidence, to address taxonomic and evolutionary questions related to parasitic organisms in aquatic environments. The articles cover a range of parasites, including apicomplexan parasites, acanthocephalans, monogeneans, nematodes, trematodes, and platyhelminthes. The research highlights the importance of integrative taxonomy in advancing our understanding of parasite diversity and its implications for fields such as biogeography, evolution, and ecology. [Extracted from the article]

Groundwater is a vital ecosystem of the global water cycle, hosting unique biodiversity and providing essential services to societies. Despite being the largest unfrozen freshwater resource, in a period of depletion by extraction and pollution, groundwater environments have been repeatedly overlooked in global biodiversity conservation agendas. Disregarding the importance of groundwater as an ecosystem ignores its critical role in preserving surface biomes. To foster timely global conservation of groundwater, we propose elevating the concept of keystone species into the realm of ecosystems, claiming groundwater as a keystone ecosystem that influences the integrity of many dependent ecosystems. Our global analysis shows that over half of land surface areas (52.6%) has a medium‐to‐high interaction with groundwater, reaching up to 74.9% when deserts and high mountains are excluded. We postulate that the intrinsic transboundary features of groundwater are critical for shifting perspectives towards more holistic approaches in aquatic ecology and beyond. Furthermore, we propose eight key themes to develop a science‐policy integrated groundwater conservation agenda. Given ecosystems above and below the ground intersect at many levels, considering groundwater as an essential component of planetary health is pivotal to reduce biodiversity loss and buffer against climate change. [ABSTRACT FROM AUTHOR]

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Eurasian perch Perca fluviatilis has been a popular model species for decades in the fields of aquatic ecology, community dynamics, behaviour, physiology and ecotoxicology. Yet, despite extensive research, the progress of integrating genomic perspective into existing ecological knowledge in perch has been relatively modest. Meanwhile, the emergence of high‐throughput sequencing technologies has completely changed the methods for genetic variation assessment and conducting biodiversity and evolutionary research. During the last 5 years, three genome assemblies of P. fluviatilis have been generated, allowing substantial advancement of our understanding of the interactions between ecological and evolutionary processes at the whole‐genome level. We review the past progress, current status and potential future impact of the genomic resources and tools for ecological research in Eurasian perch focusing on the utility of recent whole‐genome assemblies. Furthermore, we demonstrate the power of genome‐wide approaches and newly developed tools and outline recent cases where genomics have contributed to new ecological and evolutionary knowledge. We explore how the availability of reference assembly enables the efficient application of various statistical tools, and how genomic approaches can provide novel insights into resource polymorphism, host–parasite interactions and to genetic and phenotypic changes associated with climate change and harvesting‐induced evolution. In summary, we call for increased integration of genomic tools into ecological research for perch, as well as for other fish species, which is likely to yield novel insights into processes linking the adaptation and plasticity to ecosystem functioning and environmental change. [ABSTRACT FROM AUTHOR]

The relationship between spatial patterns of macrobenthic community characteristics and environmental conditions (dissolved oxygen, temperature, salinity, organic matter content and sediment particle size) was studied at 12 stations in Gorgan Bay (South Caspian Sea, Iran), seasonally in 2017. A total of 8803 individuals belonging to 11 families and 11 species were identified. Three species of polychaeta including Streblospio gynobranchiata, Tubificidae and Hediste diversicolor were the most dominant group in terms of abundance, making up 79.3% of all specimens. The highest density (4733 ind m-2) was observed at St. 1 while the lowest (1166 ind m-2) at St. 9. Biotic indices (i.e. AMBI, BOPA and BENTIX) were used to determine the quality of the bay. Gorgan bay is divided into two distinct zones (eastern and western regions) based on MDS analysis and ecological status. Generally, eastern part of the bay revealed the lowest abundance and biodiversity of macrobenthos. Our results suggest the effect of sediment particle size and TOM as significant parameters on distribution of macrobenthic community in Gorgan bay, South Caspian Sea. [ABSTRACT FROM AUTHOR]

Protection of Antarctica's biodiversity and ecosystem values is enshrined in the Protocol on Environmental Protection to the Antarctic Treaty, which provides for the designation of Antarctic Specially Protected Areas (ASPAs) to areas with outstanding values. Concern has been raised that existing ASPAs fail to prioritize areas to maximize the likelihood of ensuring the long-term conservation of Antarctic ecosystems and biodiversity. The absence of systematic and representative protection is particularly acute for inland aquatic ecosystems, which support a disproportionate amount of inland biodiversity. This paper promotes the case for overt inclusion of inland waters as a critical component of a representative protected area framework for Antarctica, thereby addressing their current underrepresentation. We set out a structured approach to enable the selection of representative freshwater systems for inclusion in the ASPA framework that, with modification, could also be applied across other Antarctic habitats. We acknowledge an overall lack of information on the biogeography of inland aquatic diversity and recommend increased use of remote data collection along with classification tools to mitigate this, as well as the need for the consideration of catchment-scale processes. Changes that accompany contemporary and anticipated climate change make the need for the conservation of representative biodiversity increasingly urgent. [ABSTRACT FROM AUTHOR]

Riparian deforestation degrades stream habitats, altering fish assemblages' structure, and composition. In contrast, secondary riparian forests can recover stream habitats and fish assemblages as they recover structural attributes and ecological processes. We evaluated whether the amount and condition of secondary riparian forests were important to conserve fish assemblages in 49 streams sites in eastern Amazonia. We related fish assemblage taxonomic and functional measures to riparian forest amount plus different habitat metrics using regression analysis. We compared assemblage measures among reference forests, abandoned pastures (open canopy), and secondary forests (closed canopy) using ANOVA tests. The amount of secondary forests had little influence on fish assemblages. Species richness, diversity, and functional richness were higher in pasture than in reference sites but returned to pre-disturbance conditions in secondary sites. However, functional evenness was lower in pasture streams and did not recover after secondary forest regrowth. Our results show that secondary riparian forest condition is important to recover some aspects of fish assemblages. However, streams bordered by these forests may have impoverished fish assemblages because some lost sensitive species may take longer to return. Avoiding riparian deforestation is the best strategy to reduce losses in aquatic biodiversity and ecosystem functions in tropical agricultural landscapes. [ABSTRACT FROM AUTHOR]

The biodiversity–ecosystem function hypothesis postulates that higher biodiversity is correlated with faster ecosystem process rates and increased ecosystem stability in fluctuating environments. Exhibiting high spatiotemporal habitat diversity, floodplains are highly productive ecosystems, supporting communities that are naturally resilient and highly diverse.We examined linkages among floodplain wetland habitats, invertebrate communities and their associated traits, and ecosystem function across 60 sites within the floodplain wetlands of the lower Wolastoq | Saint John River, New Brunswick, using structural equation modelling and Threshold Indicator Taxa ANalysis.We identified key environmental filters structuring invertebrate communities, by linking increased niche differentiation through shoreline change, flood pulse dynamics, and macrophyte bed complexity with increased taxa and functional diversity.Examination of traits linked to ecosystem functions revealed that more resilient wetlands with balance between primary productivity and decomposition as carbon sources were associated with greater functional evenness and richness, while habitat patches with elevated decomposition rates had lower functional richness, reflecting a simplified, more disturbed habitat.While our more complex overarching SEM model was ultimately compromised by an overspecified number of pathways, our results nevertheless are indicative of a divergence between wetland and riverine ecosystems in their relationships linking biodiversity and ecosystem function, illustrating how to define ecosystem health in wetland habitats, and demonstrating how critical functions support healthy wetland habitats by providing increased resilience to disturbance. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Whereas environmental impact assessment (EIA) is broadly accepted as a legal requirement for managing the marine environment in areas beyond national jurisdiction (ABNJ), there has been a greater reluctance by States to adopt strategic environmental assessment (SEA) requirements. This suggests the legal basis for SEA is different and less firmly established in international law than EIA. This article examines the distinct legal and policy roles of SEA in managing ABNJ, which then informs our understanding of its legal basis. We argue, unlike EIA's close association with due diligence obligations to prevent harm, SEA is better understood as a legal mechanism for the implementation of the principle of integration. Recognised as central to marine governance, integration has normative dimensions that must be addressed by States. SEA, we argue, is well-suited to this task. This article addresses SEA for ABNJ generally, but attention is paid to negotiations regarding marine biodiversity of ABNJ. [ABSTRACT FROM AUTHOR]

Meiobenthos (or meiofauna) are microscopic invertebrates that inhabit biofilms and interstitial spaces in rivers. They are diverse and extremely abundant, and they perform essential ecological functions by linking microbial production to higher trophic levels (e.g. macrobenthic invertebrates and fishes). However, meiobenthic communities remain poorly studied in Africa. Here, we sampled meio- and macrobenthic invertebrate communities associated with biofilms and sediments across an upstream–downstream gradient along the Olifants, Sabie and Crocodile rivers flowing through the Kruger National Park (KNP). We expected to link differences in community structure to environmental gradients as those rivers show different degrees of anthropogenic stress as they enter the park. Both meio- and macrobenthic communities differed across rivers and also structured along an upstream–downstream gradient. The upstream sites, which were the closest to the park borders, consistently showed a lower diversity in all three rivers. There, the invasive snail Tarebia granifera strongly dominated (making up 73% – 87% of the macrobenthos), crowding hard substrates, while concomitantly the abundances of biofilm-dwelling meiobenthos like nematodes and rotifers were substantially reduced. Nevertheless, the diversity and evenness of communities then tended to increase as water flowed downstream through the park, suggesting a beneficial effect of protected river reaches on benthic invertebrate diversity. However, for the Crocodile River, which makes up the southern border of the park, this trend was less conspicuous, suggesting that this river may experience the greatest threats. More generally, benthic invertebrate communities were driven by the concentrations of phosphates, sulphates, ammonium and organic matter and by substrate characteristics. Conservation implications: Meiobenthic organisms are very abundant in KNP rivers and react to environmental gradients; thus, they should be more considered for bio-monitoring or conservation of comprehensive assemblages of animals. Interestingly, protected reaches tended to show a reduced dominance of the invasive T. granifera and a higher diversity of benthic invertebrates.

Meiobenthos (or meiofauna) are microscopic invertebrates that inhabit biofilms and interstitial spaces in rivers. They are diverse and extremely abundant, and they perform essential ecological functions by linking microbial production to higher trophic levels (e.g. macrobenthic invertebrates and fishes). However, meiobenthic communities remain poorly studied in Africa. Here, we sampled meio- and macrobenthic invertebrate communities associated with biofilms and sediments across an upstream–downstream gradient along the Olifants, Sabie and Crocodile rivers flowing through the Kruger National Park (KNP). We expected to link differences in community structure to environmental gradients as those rivers show different degrees of anthropogenic stress as they enter the park. Both meio- and macrobenthic communities differed across rivers and also structured along an upstream–downstream gradient. The upstream sites, which were the closest to the park borders, consistently showed a lower diversity in all three rivers. There, the invasive snail Tarebia granifera strongly dominated (making up 73% – 87% of the macrobenthos), crowding hard substrates, while concomitantly the abundances of biofilm-dwelling meiobenthos like nematodes and rotifers were substantially reduced. Nevertheless, the diversity and evenness of communities then tended to increase as water flowed downstream through the park, suggesting a beneficial effect of protected river reaches on benthic invertebrate diversity. However, for the Crocodile River, which makes up the southern border of the park, this trend was less conspicuous, suggesting that this river may experience the greatest threats. More generally, benthic invertebrate communities were driven by the concentrations of phosphates, sulphates, ammonium and organic matter and by substrate characteristics. Conservation implications: Meiobenthic organisms are very abundant in KNP rivers and react to environmental gradients; thus, they should be more considered for bio-monitoring or conservation of comprehensive assemblages of animals. Interestingly, protected reaches tended to show a reduced dominance of the invasive T. granifera and a higher diversity of benthic invertebrates. [ABSTRACT FROM AUTHOR]

We analyzed phytoplankton assemblages' variations in oligo-mesotrophic Shchuchie and Burabay lakes using traditional morphological and next-generation sequencing (NGS) approaches. The total phytoplankton biodiversity and abundance estimated by both microscopy and NGS were significantly higher in Lake Burabay than in Lake Shchuchie. NGS of 16S and 18S rRNA amplicons adequately identify phytoplankton taxa only on the genera level, while species composition obtained by microscopic examination was significantly larger. The limitations of NGS analysis could be related to insufficient coverage of freshwater lakes phytoplankton by existing databases, short algal sequences available from current instrumentation, and high homology of chloroplast genes in eukaryotic cells. However, utilization of NGS, together with microscopy allowed us to perform a complete taxonomic characterization of phytoplankton lake communities including picocyanobacteria, often overlooked by traditional microscopy. We demonstrate the high potential of an integrated morphological and molecular approach in understanding the processes of organization in aquatic ecosystem assemblages. [ABSTRACT FROM AUTHOR]

Biodiversity is changing at an accelerating rate at both local and regional scales. Beta diversity, which quantifies species turnover between these two scales, is emerging as a key driver of ecosystem function that can inform spatial conservation. Yet measuring biodiversity remains a major challenge, especially in aquatic ecosystems. Decoding environmental DNA (eDNA) left behind by organisms offers the possibility of detecting species sans direct observation, a Rosetta Stone for biodiversity. While eDNA has proven useful to illuminate diversity in aquatic ecosystems, its utility for measuring beta diversity over spatial scales small enough to be relevant to conservation purposes is poorly known. Here we tested how eDNA performs relative to underwater visual census (UVC) to evaluate beta diversity of marine communities. We paired UVC with 12S eDNA metabarcoding and used a spatially structured hierarchical sampling design to assess key spatial metrics of fish communities on temperate rocky reefs in southern California. eDNA provided a more-detailed picture of the main sources of spatial variation in both taxonomic richness and community turnover, which primarily arose due to strong species filtering within and among rocky reefs. As expected, eDNA detected more taxa at the regional scale (69 vs. 38) which accumulated quickly with space and plateaued at only ~ 11 samples. Conversely, the discovery rate of new taxa was slower with no sign of saturation for UVC. Based on historical records in the region (2000–2018) we found that 6.9 times more UVC samples would be required to detect 50 taxa compared to eDNA. Our results show that eDNA metabarcoding can outperform diver counts to capture the spatial patterns in biodiversity at fine scales with less field effort and more power than traditional methods, supporting the notion that eDNA is a critical scientific tool for detecting biodiversity changes in aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Aquatic plants (macrophytes) are important components of freshwater ecosystems and serve numerous functions, both physical and biological, that help to structure aquatic communities. However, invasive macrophytes may negatively alter ecosystem properties. Non-native invasive species have been identified as a major cause of biodiversity loss and the increasing prevalence of invasive species has prompted studies to help understand their impacts and to conserve biodiversity. Studying mechanisms of invasion also gives ecological insight into how communities are structured and assembled. This study examined a set of potential factors influencing invasion including biotic resistance, exposure, and water depth using mixed-effects models on macrophyte survey data collected from twenty-nine lakes across the United States. The results of this study indicated that biotic resistance measured from native species richness, exposure due to fetch, and water depth interact, often in non-linear ways to influence probability of invasive species occurrence at a given location; however, models explained a relatively low percentage of variation in probabilities. It is likely that strong predictive principles governing macrophyte invasions do not exist, at least among comparisons across a range of ecosystem types and environmental conditions. However, ecologists should continue to search for general patterns within definable ecosystem units to increase understanding about factors contributing to invasibility. [ABSTRACT FROM AUTHOR]

The interpretation of biological diversity can be very complex, as it exists a dynamic based on the origin and diversification of species, in addition to anthropogenic effects, such as the introduction of invasive species, which can result in the local extinction of the native ones. The aim of this study was to analyze the temporal variation (2012 and 2017), in composition and distribution of the ichthyofauna along the Atacames River in northwestern Ecuador. In 2012 we recorded: 1) the presence of Astyanax ruberrimus, which was reported locally extinct by 2017; and 2) the tilapia (Orechromis niloticus) as the only introduced fish species present until 2017, when the addition of the non-native guppy (Poecilia gillii) occurred . In addition, the increase in human activities conduced to change in diversity, abundance and distribution of fish along the watercourse, which resulted in dispersing of some species towards the upper reaches of the river basin. [ABSTRACT FROM AUTHOR]

Biogeochemistry of iron in wetlands is inextricably linked with chemical ecology of aquatic biota impacting the ecology of wetland plants and human health. Therefore, its bio-accumulation in plants is of extreme eco-technological relevance in quest of potential phytoremediation tools. To this end, the Fe concentrations in water and four invasive alien macrophytes (Eichhornia crassipes, Lemna minor, Pistia stratiotes and Salvinia cucullata) of Loktak lake (a Ramsar Site) were measured. Further, the outcome of the present research can assess the efficiency of these plants in Fe-phytoremediation. Concomitantly, to get an explicit Fe-macrophyte's chemical ecology scenario of Loktak lake, physicochemical parameters as well as biodiversity attributes were also investigated. Results revealed that among the four plant species, Pistia stratiotes accumulated the highest amount of Fe concentration and thus act as the best bio-accumulator of Fe. Further, the extent of Fe bio-accumulation was as Pistia stratiotes>Lemna minor>Eichhornia crassipes>Salvinia cucullata. The study revealed the importance of the selected invasive wetland plants as the potential bio-agents of Fe accumulation. [ABSTRACT FROM AUTHOR]

Motivation and aim: Soil biodiversity is central to ecosystem function and services. It represents most of terrestrial biodiversity and at least a quarter of all biodiversity on Earth. Yet, research into broad, generalizable spatial and temporal patterns of soil biota has been limited compared to aboveground systems due to complexities of the soil system. We review the literature and identify key considerations necessary to expand soil macroecology beyond the recent surge of global maps of soil taxa, so that we can gain greater insight into the mechanisms and processes shaping soil biodiversity. We focus primarily on three groups of soil taxa (earthworms, mycorrhizal fungi and soil bacteria) that represent a range of body sizes and ecologies, and, therefore, interact with their environment at different spatial scales. Results: The complexities of soil, including fine‐scale heterogeneity, 3‐D habitat structure, difficulties with taxonomic delimitation, and the wide‐ranging ecologies of its inhabitants, require the classical macroecological toolbox to be expanded to consider novel sampling, molecular identification, functional approaches, environmental variables, and modelling techniques. Main conclusions: Soil provides a complex system within which to apply macroecological research, yet, it is this property that itself makes soil macroecology a field ripe for innovative methodologies and approaches. To achieve this, soil‐specific data, spatio‐temporal, biotic, and abiotic considerations are necessary at all stages of research, from sampling design to statistical analyses. Insights into whole ecosystems and new approaches to link genes, functions and diversity across spatial and temporal scales, alongside methodologies already applied in aboveground macroecology, invasion ecology and aquatic ecology, will facilitate the investigation of macroecological processes in soil biota, which is key to understanding the link between biodiversity and ecosystem functioning in terrestrial ecosystems. [ABSTRACT FROM AUTHOR]

Water bodies are the most vulnerable mean in terms of human-made impact, and the collection of monitoring information on the state of biota and the hydrochemical regime is mandatory per the recommendations of the Water Framework Convention. The paper deals with the necessary arrangements for integrated monitoring and analysis of hydrobiological and environmental analytical databases for prognostic and remediation purposes at water observation points affected by human-made chemically hazardous technogenic object (chemical weapons). The purpose of this paper was to present data of hydrobiological and hydrochemical monitoring of rivers in the area of hazardous human-made objects (chemical weapons) as recommended by the Water Framework Convention for a comparative description of the reactions of European aquatic biota to stress effects. The use of hydrobiological indices and indices of biological diversity to record the anthropogenic impact on water has been validated. The features of environmental analytical data for additional analysis of monitoring specifications dynamics have been identified. The scale parameters of hydrobiological monitoring with the calculation of α-diversity, Shannon index, saprobity index should be based on a complete examination of aquatic and semi-aquatic vegetation and flora. The analysis of the anthropogenic impact of a chemically hazardous human-made object in the Bryansk region (Russian Federation) on aquatic ecosystems over a long period of time using bioindication method (which consists in the assessment of species diversity, calculation of the Shannon index and water saprobity index) revealed that the technogenic component of the impact of reference points on watercourses is minimal. [ABSTRACT FROM AUTHOR]

Pollutants in aquatic environment tends to alter the community composition and activities of biofilm cells. The stress induced by these pollutants leads to the production of excessive reactive oxygen species (ROS) which play a key role in the degradation of pollutants in aquatic environment. This mini-review is aimed at forecasting the efficiency of the use of natural freshwater microalgae biofilm in the treatment of water resulting from mining activities. Moreover, it summarises the concept of mining by concisely stating the stages involved in mining and how the pollutants produced during mining can cause deleterious effects to aquatic flora and fauna. Environmental issues resulting from mining activities and how they hindered the progress of biodiversity were concisely discussed. Freshwater microalgae play an important role in the mitigation of the impact of pollution resulting from mining activities. The process of pollutants removal in freshwater by microalgae biofilm is by degradation and biosorption. However, it is an unestablished fact that the extracellular polymeric substances (EPS) were responsible for the biosorption of heavy metals from mining wastewater. It is also important to know the kinetic model that best explains the chemical and physical reactions of heavy metal absorption by the surface of microalgae biofilm. [ABSTRACT FROM AUTHOR]

China's rivers are highly regulated. The biodiversity and ecosystems of these rivers are threatened by barriers restricting fish movements for reproduction and foraging. To overcome this challenge, several fishways are built across the country. However, the status of fishways is not well investigated. Based on published articles, library archives, and public interviews, we have identified type, location and period of fishways construction. We have then evaluated the performance of fishways. Up until 2018, the total number of fishways in China was estimated to be 150, where 82 of them have been analyzed in this study. The pool-type fishway is the most dominant fishway type, which accounts for 83%. The slope pattern of the 49 pool-type fishways shows that the slope tends to decrease with increasing lifting height. The performance of the fishways was best observed by the successful crossing of different species of fish in Yangtze and Pearl River basins when the slopes were 1:63–1:95. When many dams in China are already facing critical challenges for adopting the right type of fishways, the pool-type fishways with variable adjustments of slopes could be an effective option for successful fish migrations in regulated river systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • The community structure of planktonic and benthic diatoms exhibited significant variations. • The biodiversity of planktonic and benthic diatoms showed exhibited significant variations. • The dispersal limitation dominated the assembly of planktonic and benthic diatom communities. • The dispersal limitation contributes more to the benthic diatom community assembly. Diatoms are an indispensable component of river ecosystem biodiversity and play an important role in aquatic ecosystems. The community assembly mechanism of diatoms has always been a central issue in the study of aquatic ecology. In recent years, many measures have been implemented in the Ashi River Basin (ASRB) to promote social and economic development, such as bridge construction, river bottom sand mining, agricultural irrigation, and urban expansion. However, there are few studies on the effects of these activities on the mechanism of diatom community assembly. First, we found that the α- and β-diversity of planktonic diatoms was higher in the normal season, while the α- and β-diversity of benthic diatoms was higher in the dry season, and the α- and β-diversity of both planktonic and benthic diatoms was reduced in the wet season. Second, the community structures of planktonic and benthic diatoms were significantly different in different hydrological periods, and the differences between planktonic diatoms communities were more evident than those between benthic diatom communities. Third, distance-decay analysis indicated that the distribution of the two types of diatom communities in the ASRB was influenced by both dispersal limitation and environmental selection. Finally, variance partitioning analysis revealed that dispersal limitation was the dominant driving factor for the spatial and temporal differentiation of planktonic and benthic diatoms. Our study reveals the important role of dispersal limitation in the community assembly of planktonic and benthic diatoms in rivers under different hydrological conditions. This study provides new insights for further understanding the relative importance of niche theory and neutral theory to aquatic microbial community assembly. Our research provides key information for analysing the structure of aquatic ecosystems and basic data for designing biodiversity conservation strategies in China's cold watersheds. [ABSTRACT FROM AUTHOR]

This report presents the outcome of the joint work of PhD students and senior researchers working with DNA-based biodiversity assessment approaches with the goal to facilitate others the access to definitions and explanations about novel DNA-based methods. The work was performed during a PhD course (SLU PNS0169) at the Swedish University of Agricultural Sciences (SLU) in Uppsala, Sweden. The course was co-organized by the EU COST research network DNAqua-Net and the SLU Research Schools Focus on Soils and Water (FoSW) and Ecology - basics and applications. DNAqua-Net (COST Action CA15219, 2016-2020) is a network connecting researchers, water managers, politicians and other stakeholders with the aim to develop new genetic tools for bioassessment of aquatic ecosystems in Europe and beyond. The PhD course offered a comprehensive overview of the paradigm shift from traditional morphology-based species identification to novel identification approaches based on molecular markers. We covered the use of molecular tools in both basic research and applied use with a focus on aquatic ecosystem assessment, from species collection to the use of diversity in environmental legislation. The focus of the course was on DNA (meta)barcoding and aquatic organisms. The knowledge gained was shared with the general public by creating Wikipedia pages and through this collaborative Open Access publication, co-authored by all course participants. [ABSTRACT FROM AUTHOR]

Global biodiversity decline is believed to be caused by high anthropopressure. Particularly vulnerable habitats are freshwater ecosystems, which are hotspots of biodiversity. The threat to these ecosystems are cyanobacterial blooms, which tend to proliferate in the face of climate changes. Cyanobacteria development and dominance affect the whole food web, especially the zooplankton community. We used three classical biodiversity indexes (species richness, Simpson's Diversity Index and Shannon Diversity Index) and three functional diversity indexes (functional richness, functional evenness and functional divergence) to study the impact of cyanobacterial bloom on the zooplankton community. The study was conducted in water bodies with a different period of bloom duration (short-lasting blooms vs. long-lasting blooms) in order to determine the impact of the proliferated blooms on the aquatic ecosystems. Use of functional diversity indexes allowed for identifying changes that can be overlooked by classical biodiversity indexes. We conclude that cyanobacterial bloom involves modifications of functional trait space of studied communities and, in consequence, functioning of aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Turkey is among the countries with the richest biodiversity in Europe and the Middle East; it ranks ninth in the European continent in terms of biodiversity. Its distinct and varied geography affords a high level of endemism and genetic diversity. Due to its high level of endemism and genetic diversity, Turkey is also a center of attraction in terms of genetic resources. This raises the issue of bio-smuggling, which is a significant problem that threatens both the biodiversity and the economic future of the country. The insufficiency of legal, political and institutional systems are a major determining factor on the problem of bio-smuggling in Turkey. Although there are 50 different legislations (11 different international conventions, 14 different laws, 2 different statutory decrees, and 23 different specific regulations) germane to bio-smuggling, between 2002 and 2015 59 incidents of bio-smuggling were documented. Prevention of bio-smuggling in Turkey has remained low and insufficient. With this study, we will review and examine several case examples: legal ramifications of combatting bio-smuggling; pertinent national regulations; legal and administrative sanctions against bio-smuggling and their effectiveness. [ABSTRACT FROM AUTHOR]

Predicted trends towards more intense droughts are of particular significance for running water ecosystems, as the loss of critical stream habitat can provoke sudden changes in biodiversity and shifts in community structure. However, analysing ecological responses to the progressive loss of stream habitat requires a continuous disturbance gradient that can only be generated through large‐scale manipulations of streamflow.In the first experiment of its kind, we used large artificial stream channels (mesocosms) as analogues of spring‐fed headwaters and simulated a gradient of drought intensity that encompassed flowing streams, disconnected pools, and dry streambeds. We used breakpoint analysis to analyse macroinvertebrate community responses to intensifying drought, and identify the taxa and compositional metrics sensitive to small changes in drought stress.We detected breakpoints for >60% of taxa, signalling sudden population crashes or irruptions as drought intensified. Abrupt changes were most pronounced where riffle dewatering isolated pools. In the remnant wetted habitat, we observed a shift to larger body sizes across the community, primarily driven by irruptions of predatory midge larvae and coincident population collapses among prey species (worms and smaller midges).Our results suggest that intense predation in confined, fragmented stream habitat can lead to unexpected changes in body sizes, challenging the conventional wisdom that droughts favour the small. Pool fragmentation might thus be the most critical stage of habitat loss during future droughts, as the point at which impacted rivers and streams begin to exhibit major shifts in fundamental food web properties. [ABSTRACT FROM AUTHOR]

Analysis of environmental DNA (eDNA) offers an unprecedented ability to accurately survey biodiversity from aquatic ecosystems. Although eDNA methods have been applied to myriad taxa, scientists are now moving away from proof-of-concept work, ultimately evaluating the limits and opportunities of this technology to detect and quantify abundance across organisms and environments. Important considerations enabling such methodology to be used for aquatic conservation contexts includes understanding both the effects of (1) the amount of eDNA released from focal taxa—sources, and (2) the removal of eDNA in the environment—sinks. I review publications on aquatic macroorganism eDNA that have evaluated or considered the effect of sources on signal detection (or quantification) and find few studies acknowledge, and fewer still evaluate, the impact of eDNA production on genomic signal recovery. In this review, I encourage readers to carefully consider source dynamics, and using previously published literature, dissect what roles biotic (e.g. life-history traits, species interactions including stressors) and abiotic (e.g. temperature, salinity) factors likely play in eDNA deposition and recovery, and how this impacts detection, abundance, biomass estimation, and ultimately informed signal interpretation. I further explore the physical sources of eDNA and propose other methods (spatial and temporal) and markers to assist in identifying eDNA origins in aquatic systems. Understanding how these parameters influence variation in eDNA sources will allow for a more comprehensive survey tool, and potentially give insights into environment-population responses. [ABSTRACT FROM AUTHOR]

Predicted increases in the human population, in a context of climatic change and limiting freshwater resources, have raised awareness of the need to preserve aquatic ecosystems, their functions, and the biodiversity they harbor. The ecological reconciliation approach proposes the long-term co-existence of biodiversity preservation and the development of human activities. We investigated the ecological and evolutionary contributions of irrigation and hydroelectric canals in the highly fragmented and regulated Durance River (Rhône basin, Southern France), to the genetic diversity patterns of two interbreeding cyprinid species, the native Parachondrostoma toxostoma, and the introduced Chondrostoma nasus species. We observed a high degree of genetic homogeneity along the length of the river. The maintenance of gene flow despite the presence of dams, and the detection of admixed populations and hybridization events in canals suggest that these canals may act as ecological corridors and hybrid zones with the potential to influence genetic resources for the native and introduced species. These anthropogenic structures vary considerably in terms of their spatial organization, size, and overall management, increasing habitat diversity in the urbanized section of river. Together with the restoration of natural habitats, canals can be considered as important structures for biodiversity dynamic in such urban conditions. [ABSTRACT FROM AUTHOR]

Water quality and stream habitat in agricultural watersheds are under greater scrutiny as hydrologic pathways are altered to increase crop production. Ditches have been traditionally constructed to remove water from agricultural lands. Little attention has been placed on alternative ditch designs that are more stable and provide greater habitat diversity for wildlife and aquatic species. In 2009, 1.89 km of a conventional drainage ditch in Mower County, Minnesota, was converted to a two‐stage ditch (TSD) with small, adjacent floodplains to mimic a natural system. Cross section surveys, conducted pre‐ and post‐construction, generally indicate a stable channel with minor adjustments over time. Vegetation surveys showed differences in species composition and biomass between the slopes and the benches, with changes ongoing. Longitudinal surveys demonstrated a 12‐fold increase in depth variability. Fish habitat quality improved with well‐sorted gravel riffles and deeper pool habitat. The biological response to improved habitat quality was investigated using a Fish Index of Biological Integrity (FIBI). Our results show higher FIBI scores post‐construction with scores more similar to natural streams. In summary, the TSD demonstrated improvements in riparian and instream habitat quality and fish communities, which showed greater fish species richness, higher percentages of gravel spawning fish, and better FIBI scores. This type of management tool could benefit ditches in other regions where gradient and geology allow. Research Impact Statement: Two‐stage ditch construction improved riparian and instream habitat conditions for wildlife and fish communities, thus a tool for watershed managers. [ABSTRACT FROM AUTHOR]

The biodiversity of shallow (zmax < 5-7 m) lakes is sensitive to water-level and climate changes, but few such aquatic ecosystems have been studied in the context of quantitative climate reconstruction. Lac Lili (unofficial name) is located in the boreal forest of western Quebec, Canada, and was chosen for its shallowness (zmax = 1.40 m) to assess if chironomid assemblages in the sediments could be used to reconstruct Holocene temperature fluctuations quantitatively. Inferred temperatures displayed a decreasing trend from a maximum value ca. 8000-3500 cal year BP, slight warming between ca. 3500 and 3000 cal year BP, followed by cooling to the present. Although chironomid assemblages were influenced by factors other than climate, primarily water depth and changes in macrophyte richness, the reconstructed Holocene temperature pattern was very similar to the known regional climate history. Temperature inferences derived from the chironomid assemblages were, however, warmer than the two reference periods. This deviation was likely a consequence of three factors: (1) shallowness of the lake, which favoured littoral taxa with warmer-than-today temperature optima, (2) the low number of lakes warmer than 16 °C in the training set, and (3) the absence of shallow lakes in the training set. [ABSTRACT FROM AUTHOR]

Seagrass meadows are highly productive habitats that support commercially and ecologically important fishes and invertebrates. However, evidence of fish-habitat relationships are seldom drawn from forereef seagrass meadows that are structurally simple in terms of species richness and relative size and, consequently, their role as habitats is unclear. In this study, fish-habitat relationships were examined in such meadows in the forereef seagrasses of Tinggi Island and Babi Besar Island, Malaysia, by documenting habitat complexity attributes (canopy height, shoot density and percent cover), distance to adjacent coral reefs, and water depth within 2×2 m quadrats. Fish assemblages were recorded using the Remote Underwater Video Station method. A total of 1166 individuals from 86 taxa were found and enumerated. This study showed that (1) fish density and species richness were significantly associated with seagrass percent cover alone; (2) commercially important carnivores formed the majority of the fish populations in the meadows, and (3) fish density and species richness were positively correlated with distance to the nearest adjacent coral reef, indicating the need to account for the effects of neighboring habitats in studies of this nature. Thus, structurally simple seagrass meadows are still important fish habitats, especially as feeding grounds for commercially significant carnivores. [ABSTRACT FROM AUTHOR]

Highlights • The eco-exergy and biomass of macrobenthos were decreased during mangrove succession. • The specific eco-exergy of macrobenthos was constant during mangrove succession. • Self-organization of macrobenthos was sensitive to plant and soil properties. • Macrobenthos conservation deserves more attention in mature mangroves. Abstract Eco-exergy (ecological exergy) has been used to evaluate the health and self-organization of aquatic and wetland ecosystems following perturbation or natural succession. Although macrobenthic fauna are important components of mangrove ecosystems, their self-organization during mangrove succession is unclear. In this study, eco-exergy was used to quantify the self-organization processes of macrobenthic faunal assemblages in a mangrove chronosequence that included a primary (unvegetated shoal), early (Avicennia marina), middle (Aegiceras corniculatum), and late (Bruguiera gymnorrhiza + Rhizophora stylosa) community in Zhanjiang, China. Eco-exergy and biomass of the macrobenthic faunal community tended to decrease in the wet season during mangrove succession. The specific eco-exergy of the macrobenthic faunal community, in contrast, remained relatively constant in both wet and dry seasons during mangrove succession, although mollusk eco-exergy tended to decrease and arthropod eco-exergy tended to increase. Statistical analyses indicated that the self-organization of the macrobenthic faunal community during mangrove succession was mainly associated with the development of a suite of vegetation characteristics and sediment physicochemical properties, e.g., plant crown breadth, plant density, sediment ammonium nitrogen and sediment total nitrogen. Unlike the diversification trends of species richness and functional groups, this study confirmed the decreased self-organization trend of macrobenthic fauna assemblage mainly derived from biomass and genetic information. These results highlight the importance of conserving the macrobenthic faunal community in mangrove forests, especially in the late successional stages. [ABSTRACT FROM AUTHOR]

Fish and microhabitat data were collected at 542 prepositioned electrofishing sites (surface area of each site = 4 m2) in the Kootenai River, Idaho, during 2014 and 2015 to evaluate small‐scale habitat use by fishes, as it relates to large‐scale habitat rehabilitation efforts. Samples were collected from a 12‐km braided segment of river that had received localized habitat rehabilitation treatments since 2011. Fish and microhabitat data were collected to investigate habitat drivers related to the occurrence and relative abundance of fishes. Each sampling location was selected at random and characterized as "treated" (i.e., rehabilitated) or "untreated" based on proximity to habitat treatments. Fishes sampled from backwaters composed 71% of the overall catch and 84% of the catch from locally untreated areas of the river. Species‐specific regression models suggested that water depth and current velocity influenced the occurrence and abundance of fishes. In particular, shallow habitats with low current velocities were important for small‐bodied native fishes and likely serve as important rearing areas for juvenile fish. These habitat conditions typically characterize backwater and channel‐margin habitats that are vulnerable to anthropogenic perturbation. Prioritizing process‐based rehabilitation of these areas in large, regulated rivers would allow natural channel‐forming processes for the benefit of native fishes. [ABSTRACT FROM AUTHOR]

Keystone species can provide a focal point for designing conservation and management strategies that protect a diversity of social–ecological values in aquatic ecosystems; however, to avoid bias towards a subset of values associated with a single activity, such as fishing, stakeholder consultations must cover a spectrum of social perspectives.Using the Murray crayfish (Euastacus armatus) as a model, this study explored how Aboriginal Traditional Owners, landowners, tourism businesses, scientific researchers, non‐governmental organizations, and government agencies valued this threatened freshwater species across south‐east Australia.Qualitative methods revealed that E. armatus is a culturally significant species, targeted for fishing, but is also valued for a range of non‐extractive reasons that support social–ecological linkages between people and freshwater ecosystems.Perceived as an iconic species by most stakeholders, there was general support for E. armatus to be used as a flagship for conserving a spectrum of social–ecological values (e.g. Aboriginal Traditional Owner totem species), attached to their local freshwater ecosystems. Although stakeholders were conflicted over whether fishing should continue, four themes emerged on how to develop more equitable and effective conservation and management strategies: increased public education, co‐management with non‐government stakeholders, federal government co‐ordination, and spatial protection of critical areas.The protection of aquatic species in ways that support their full range of cultural, economic, and ecological values will require more bottom‐up (i.e. stakeholder‐led) approaches to conservation and management design. Broader stakeholder engagement and co‐management should reduce perceptions that local stakeholders are isolated from management processes, while increasing the capacity and confidence of managers to implement strategies that bolster both the social and ecological resilience of aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Round goby (Neogobius melanostomus) are invasive benthic fish native to the Black and Caspian Seas of Eurasia. First documented in the Chicago Area Waterway System in 1993, this aggressive species has been progressing from Lake Michigan toward the Mississippi River via the Illinois River. Here we describe the history of round goby monitoring in the Illinois River and the more recent annual efforts by the U.S. Fish and Wildlife Service to document the expansion of round goby toward the Mississippi River using multiple gears. From 2014 to 2017, annual monitoring has documented the expansion of round goby in the lower Illinois River to within 55 rkm of the Mississippi River, beyond previously published capture locations. Although it is unclear whether or not round goby are reproducing this close to the Mississippi River or if a population is established, their presence is concerning considering their deleterious impacts to native species in other systems. Additionally, the Mississippi River and its tributaries provide an abundance of preferred spawning habitats that could facilitate the expansion of self-sustaining populations throughout the Upper Mississippi River watershed. We urge the development of more robust monitoring and management strategies designed to identify and mitigate the potential impacts of this species. [ABSTRACT FROM AUTHOR]