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This poster was presented at the California Invasive Plant Council 2023 Symposium, the Merced Vernal Pool and Grassland Reserve 10th Anniversary Symposium, and the 2024 California Society for Ecological Restoration conference.The California Rapid Assessment Method (CRAM) is a level 2 landscape quality surveying method. Wetlands are rated on their buffer/landscape context, hydrology, physical structure, and biotic structure. Certified practitioners are trained and calibrated such that CRAM scores are standardized throughout the state. This allows for state-wide comparisons and analysis of wetlands across sites, projects, and managers. Here, we present comparisons of CRAM scores for natural and restored vernal pool wetlands across the state. This allows us to assess how restoration projects compare to natural ecosystems, and also allows us to target specific regions or landscape metrics for future restoration.

Microplastics generated from diverse categories of plastic wastes primarily accumulate in terrestrial ecosystems and subsequently find their way to aquatic ecosystems. As the use of plastic goods has been increasing globally during the last few decades, it is likely that the amount of microplastics too would increase significantly and get accumulated in the soil. An increased level of microplastics might have deleterious effects on soil properties and microbiota. Microplastics being small (< 5 mm), could be easily consumed by pedophagous soil fauna such as earthworms and get dispersed widely in soil and might even reach the groundwater table. It has been reported that microplastics such as polyvinyl chloride, polypropylene etc., can bind to toxic compounds, including pesticides and transfer these into the gut of earthworms, adversely impacting their growth, ecological functions, and reproduction. It is apprehended that earthworms and other soil fauna could accelerate the degradation of microplastics into nano forms which could enhance environmental risk not only for these animals but also for other beneficial soil biotas. [ABSTRACT FROM AUTHOR]

Determining if ecological communities are saturated (have a limit to the number of species they can support) has important implications for understanding community assembly, species invasions, and climate change. However, previous studies have generally been limited to short time frames that overlook extinction debt and have not explicitly considered how functional trait diversity may mediate patterns of community saturation. Here, we combine data from biodiversity surveys with functional and phylogenetic data to explore if the colonisation events after the Great American Biotic Interchange (closure of the Panamanian Isthmus) resulted in increases in species richness of communities of the snake family Dipsadidae. We determined the number and the direction of dispersal events between Central and South America by estimating ancestral areas based on a Bayesian time-calibrated phylogenetic analysis. We then evaluated whether variation in community saturation was mediated by the functional similarity of six traits for the resident and colonizing snakes and/or local environmental conditions. We found that colonised communities did not support more species than those that were not colonised. Moreover, we did not find an association between the functional diversity across sites and whether they were colonised by members from the lineages dispersing across the Isthmus or not. Instead, variation in species richness was predicted best by covariates such as time since colonisation and local environment. Taken together, our results suggest that snake communities of the Dipsadidae across the neotropics are saturated. Moreover, our research highlights two important factors to consider in studies of community saturation: extinction debt and the functional differences and similarities in species' ecological roles.

We have carried out a correlation analysis to study relationships between the trace element (TE) composition of mud-volcanic and carbon dioxide fluids in the Greater Caucasus on the one hand and the chemical composition of upper, middle, and lower crust, as well as various kinds of biota on the other hand. It has turned out to be possible to relate the roots of the associated fluid flows with definite stages of the Earth's crust, as well as to point out, in several cases, the kind of the dominant original organic matter. The roots of both carbon dioxide fluids and mud-volcanic fluids were shown to reside in the middle crust. We have compared correlative relationships for deep-seated fluids in the Caucasus with those for oils in several major oil-gas basins in Russia and in the fluid systems of Kamchatka. [ABSTRACT FROM AUTHOR]

Microplastics are small plastic materials often defined as those between 5 mm and 0.05 mm in size. Microplastics can have toxicological impacts on various biota, from gut blockages to the transport or leaching of toxicants used in their production or absorbed from the surrounding environment. Although microplastic research has increased significantly, microplastic research in Africa lags behind that of developed countries. South Africa is the African nation with the highest number of microplastic publications. We aimed to determine the current state of microplastic research in South Africa. A total of 46 publications on microplastics in South Africa have been produced. However, many of these publications use methods that might not be accurate in determining holistic descriptions of microplastics in the aquatic environment. Similarly, many ecologically relevant environments and species have not been investigated for microplastics in the country, including any atmospheric or terrestrial environment. We conclude that, although the research being produced in South Africa can be considered adequate, a singular standard method for sampling and assessing microplastics in South African environments is required. The production of such a standard method would be critical to use as a monitoring tool to determine and compare microplastic abundances across the country and globally. Significance: • More than 40 publications on microplastics have been produced in South Africa. • Microplastics have been discovered in multiple aquatic environments in South Africa, but have not been investigated in atmospheric or terrestrial environments. • Polymer analysis was limited in published research. • A standard method is required for comparing between studies. • Terrestrial and atmospheric microplastic studies are required. [ABSTRACT FROM AUTHOR]

We carried out measurements of the CO2 system parameters to evaluate the impact of carbonate and nutrients' chemistry on phytoplankton populations in the Gulf of Guinea (GoG). The seasonal variations of the CO2 system parameters (fCO2, DIC, pH and TA) along with nitrates and phosphates were quantified weekly at surface (between 0 and 5 m depth) (5.57°N - 4.57°W) in the GoG from May to December 2020. Seawater pH varied widely during the study period, ranging between 8.10-8.35 pH units; DIC and TA varied between 1810 and 2094 mmol kg-1, and between 2051 and 2216 mmol-1 respectively. DIC peaks coincided with the high upwelling period (August and September). For phytoplankton, a total of 60 species were found belonging to four taxonomic phyla: Bacillariophyta, Dinophyta, Chlorophyta and Dictyochophyta. The highest number of phytoplanktonic species were recorded for Bacillariophyta phylum with 36 species (60%). The phylum Dinophyta comprised 22 taxa (36%) and Chlorophyta and Dictyochophyta recorded only one species (2%). The highest specific diversities were observed in August and September with 29 and 26 taxa respectively and the lowest was found in October-November (5 taxa) and December (one taxa). Bacillariophyta and Dinophyta appeared throughout the entire study period. The only species for Chlorophyta phylum appeared in June and July and the Dictyochophyta's one in May, July and August. In general, the physical (SST, SSS) and chemical (TA, DIC, pH) parameters influenced less than 50% of the phytoplankton population in the coastal area of the GoG. Our study shows that Bacillariophyta population grows up when the physicochemical parameters' variability increase. [ABSTRACT FROM AUTHOR]

The Cretaceous Period is a vital time interval in deciphering the evolutionary history of the Neo-Tethys Ocean and the convergence of different plates and blocks across the Qinghai-Tibetan Plateau. A detailed stratigraphic framework and paleogeographic patterns are the basis for understanding the evolution of the Neo-Tethys Ocean and the formation of the Qinghai-Tibetan Plateau. Here, the Cretaceous stratigraphy, biota, paleogeography, and major geological events in the Qinghai-Tibetan Plateau are analyzed to establish an integrative stratigraphic framework, reconstruct the paleogeography during the Cretaceous Period, and decode the history of the major geological events. The Cretaceous rocks of the Qinghai-Tibetan Plateau and its surrounding area are predominantly marine deposits, with a small amount of interbedded marine-terrestrial and terrestrial conponents. The Indus-Yarlung Tsangpo Suture Zone was responsible for the deposition of deep marine sediments dominated by ophiolite suites and radiolarian silicalite. To the south, the Tethys Himalayas and Indus Basin received marine sediments of varying depths and lithology; to the north, the Xigaze and Ladakh forearc basins are also filled with marine sediments. The Lhasa Block, Karakorum Block, western Tarim Basin, and West Burma block consist of shallow marine, interbedded marine-terrestrial, and terrestrial sediments. The Qiangtang Basin and other areas are dominated by terrestrial sedimentation. The Cretaceous strata of the Qinghai-Tibetan Plateau and its surrounding areas are widely distributed and diversified, with abundant foraminifera, calcareous nannofossils, radiolarians, ammonites, bivalves, and palynomorphs. On the basis of integrated lithostratigraphic, biostratigraphic, geochronologic, and chemostratigraphic analyses, we proposed herein a comprehensive stratigraphic framework for the Cretaceous Period of the eastern Neo-Tethys. By analyzing the Cretaceous biota of different biogeographic zones from eastern Neo-Tethys and its surrounding areas, we reconstructed the paleobiogeography of different periods of eastern Neo-Tethys. The Cretaceous paleogeographic evolution of the Qinghai-Tibetan Plateau and its surrounding areas can be divided into three phases: (1) gradual breakup of the Indian Plate from the Australia-Antarctica continent and the early collision phase of the Lhasa-Qiangtang blocks (145–125 Ma); (2) northward drift of the Indian Plate and the collision phase of the Lhasa-Qiangtang blocks (125–100 Ma); (3) rapid northward drift of the Indian Plate, formation of the Tarim-Tajik-Karakorum Bay, and early uplift of the Gangdise Mountains (100–66 Ma). The Indus-Tethys Himalayan biota underwent a transition from the cold-water type in the high latitudes of the southern hemisphere to the warm-water type near the equator from the Early Cretaceous to the Mid-Cretaceous. The biodiversity and abundance of the eastern Neo-Tethys Ocean increased gradually in the Early Cretaceous, peaking in the Mid-Cretaceous, and decreased sharply during the late Late Cretaceous (late Maastrichtian). Along with the northward drift of the Indian Plate and subduction of the Neo-Tethys, the eastern Neo-Tethys and its surrounding areas experienced a series of major geological events, including the formation of the large igneous province, oceanic anoxia events, and mass extinction, etc. [ABSTRACT FROM AUTHOR]

The Qinghai-Tibetan Plateau and its surrounding areas have a long and complex tectonic evolutionary history. Cratons and blocks, such as northern India, Lhasa, Qiangtang, Qaidam and Central Qilian, and their in-between orogenic belts constitute the main part of the Qinghai-Tibetan Plateau. During the Cambrian Period, most of these cratons and blocks were on the northwestern periphery of Gondwana, and were associated with the surrounding blocks, e.g. Arabian, Central Iran, Afghanistan, Tarim, Alxa, North China, South China and Sibumasu through the Proto-Tethys Ocean. The Cambrian stratigraphic sequences on these stable blocks are composed of mixed siliciclastic and carbonate rocks deposited in the shallow-water marine environments, and contain the trilobite assemblages of shelf facies. The Cambrian stratigraphic sequences in the Qilian tectonic belts, however, are characterized by the intermediate-basic igneous rocks and silicates formed in the Proto-Tethys Ocean, and contain the trilobite assemblages of deep-water slope facies. Combining with previous data, field observations and newly discovered fossils through funding by the Second Tibetan Plateau Scientific Expedition and Research, the general characteristics of the Cambrian strata in different tectonic units of the Qinghai-Tibetan Plateau and its surrounding areas have been summarized in this paper. Furthermore, efforts have been made to subdivide and correlate the Cambrian strata across these areas by utilizing available biostratigraphic and geochronological data. As a result, a comprehensive litho- and biostratigraphy chart has been compiled. Finally, from the biogeographic perspective, this paper also provides a brief overview of the Cambrian paleogeographical reconstruction of the major tectonic blocks, and discusses the problems associated with the evolution of the Proto-Tethys tectonic belt. [ABSTRACT FROM AUTHOR]

The Quaternary strata on the Qinghai-Tibet Plateau contain rich information about the paleoclimate and environmental evolution, record the evolution process of the Quaternary regional tectonics, paleogeography, and geomorphology of the plateau, and are extremely important areas for studying the Quaternary geological events and regional environmental evolution. According to a comprehensive analysis of the regional stratigraphic data and the development and evolution characteristics of the biota, based on the differences in the lithostratigraphic units, sedimentary characteristics, landforms, and drainage systems, the Quaternary strata on the Qinghai-Tibet Plateau and its surrounding areas are divided into five stratigraphic regions: the Tarim region, Loess Plateau region, Qinghai-Tibet Plateau region, Yunnan-Guizhou Plateau region, and India-Ganges region. The Qinghai-Tibet Plateau stratigraphic region is divided into seven stratigraphic sub-regions: the West Kunlun-Karakorum, Altun-Qilian Mountains, Qaidam-Hehuang, East Kunlun-Bayan Har, Qiangtang, East Xizang-West Yunnan-West Sichuan, and Gangdise-Himalayan sub-regions. This paper briefly describes the lithostratigraphic units of the seven stratigraphic sub-regions of the Qinghai-Tibet Plateau. According to the lithostratigraphic sequence and its sedimentary characteristics, stratigraphic contact relationship, formation age, and evolution of the biota in each stratigraphic sub-region, the Quaternary tectonic paleogeographic evolution of the Qinghai-Tibet Plateau is divided into four stages. (1) The inherited differential uplift stage since the Pliocene (2.6−1.8/1.5 Ma): the regional sedimentary differences were significant, and the stratigraphic distribution was limited, the alluvial-proluvial sandy conglomerate was widely developed along the piedmont, and fluvial and lacustrine deposits were developed in the low-lying areas between the mountains. (2) The mountain range flattening stage (1.8/1.5−1.2/0.8 Ma): the erosion unconformity surfaces around the plateau were widely distributed, large rivers were formed, and lake sediments developed in the intermountain basins and the hinterland of the plateau. (3) 1.2/0.8−0.128 Ma: the plateau continued to rise in a large range, with significant topographic differences and intensified mountain erosion. At about 0.8 Ma, the plateau uplifted above the snow line and entered the cryosphere, mountain glaciers developed, and the alpine arid environment gradually formed. (4) 0.128 Ma-: the mountains rose and erosion intensified, and intermountain basins and lakes were widely distributed. There were significant differences in the regional sedimentary characteristics, and the sedimentary types developed toward diversification. The modern plateau landform pattern was basically formed. [ABSTRACT FROM AUTHOR]

The complex evolutionary history of the Qinghai-Tibetan Plateau and its surrounding areas, including the continental blocks (Indian, Lhasa, South Qiangtang, Tarim, Olongbuluk, Central Qilian, Alxa, North China, Yangtze, Central Iran and Oman) and the orogenic belts between them, has long been the frontier in Earth science research. The Cryogenian and Ediacaran strata are extensively distributed in these blocks. Specifically, relatively complete Cryogenian and Ediacaran successions have been discovered in Oman, Indian, Yangtze, and Tarim blocks, while only the Ediacaran successions have been reported in Iran, the South Qiangtang, Central Qilian, Alxa, and North China blocks. Based on previous studies together with the integration of new materials and advancement obtained through the Second Tibetan Plateau Scientific Expedition and Research, this review aims to synthesize a correlative stratigraphic framework of the representative Cryogenian and Ediacaran sequences from the Qinghai-Tibetan Plateau and its surrounding areas. Furthermore, the Cryogenian and Ediacaran biotas and major geological events in these areas are comprehensively discussed in aspects of current research status. The results indicate that, in general, Ediacaran fossils of each area exhibit distinct features in preservation and assemblage composition, but the typical late Ediacaran fossils Cloudina and Shaanxilithes have been reported from most of these areas. In addition to the two global Cryogenian glaciations, late Ediacaran glaciogenic deposits are extensively recorded in the areas within and around the northern Qinghai-Tibetan Plateau (including the North China, Alxa, Central Qilian, Olongbuluk, and Tarim blocks, and the North Qilian Accretionary Belt), as well as central and southern Iran. However, further research is required to determine the age, distribution, and origin of these late Ediacaran glaciogenic deposits. Meanwhile, the middle Ediacaran DOUNCE/Shuram Excursion is widely documented in the Qinghai-Tibetan Plateau and its surrounding areas. The available data show that, after the break-up of the Rodinia supercontinent, most of the continental blocks in the areas were located along the northern margin of East Gondwana and a few (such as North China) were located between the Gondwana and Laurentia. In general, the paleogeographic evolution of most of these blocks during the Cryogenian and Ediacaran remains disputatious, necessitating further research to resolve the controversies surrounding their paleogeographic reconstruction models during this critical time interval. [ABSTRACT FROM AUTHOR]

During the Carboniferous Period, the Qinghai-Tibetan Plateau and its surrounding areas were located in quite different paleogeographic positions with various sedimentary and biological types. It is important to systematically compile and summarize the Carboniferous strata and biotas of the Qinghai-Tibetan Plateau and its surrounding areas, to establish an integrated stratigraphic framework for correlation, and to reconstruct the paleogeography for correctly understanding the breakup of the Gondwana Continent and the evolution of the Paleo-Tethys Ocean in the Late Paleozoic. The Carboniferous of the Qinghai-Tibetan Plateau and its surrounding areas can be subdivided into the Gondwanan, Cimmerian, and Tethyan types. The Gondwanan-type Carboniferous are distributed in the North Himalayan, Kangmar-Lhunze, and Zanda-Zumba regions of the South Tibet Subprovince and northern India-Pakistan Area, where only the Mississippian is developed and the biota is of Gondwanan affinity. The Cimmerian-type Carboniferous, which are found in the Baoshan, Tengchong, Coqen-Xainza, Lhasa-Zayu, Nagqu-Biru, and South Qiangtang regions, as well as Shan-Thai and South Afghanistan-Pamir areas, also represent only the Mississippian strata, but their biota is characterized by mixed characters of European, South China, Australian, and North American types. The Tethyan-type Carboniferous are distributed in the Tanggula Mountains, Hoh Xil-Bayanhar, Chamdo-Hengduanshan, Tiekelike, West Kunlun, Karakorum, East Kunlun-Central Qinling, and Qilian regions, where the Carboniferous succession is well developed, and the biota is of warm-water Tethyan affinity. The biostratigraphical correlation of the Gond-wanan-type and Cimmerian-type Carboniferous is based mainly on conodonts and additionally on brachiopods and rugose corals. The Mississippian of the Tethyan-type Carboniferous is correlated mainly by using rugose corals and brachiopods, whereas in the Pennsylvanian foraminifera (fusuline) and conodonts are regarded as primary fossil groups, subordinated by rugose corals and brachiopods. Adhering to the International standard chronostratigraphy of the Carboniferous, we have reconstructed a framework of the litho- and biostratigraphic subdivision and correlation of the Qinghai-Tibetan Plateau and its surrounding areas. Further studies should focus on isotope geochronology, geochemistry, paleoclimates, and paleoenvironments of the Carboniferous in the Qinghai-Tibetan Plateau and its surrounding areas. [ABSTRACT FROM AUTHOR]

The ecological integrity of several freshwater ecosystems has been disrupted by the rapid and unrestrained accumulation of toxic heavy metals (HMs) from various sources. Changes in land use and land cover, in the form of urbanization and industrialization, have significantly affected the surface-water quality of freshwater ecosystems by causing an upsurge in pollutant loads. In addition, agricultural runoff has contributed to the decrease in water quality. Almost 70% of India's surface-water resources have become polluted owing to the discharge of untreated sewage and industrial effluents, according to a recent report by the Central Water Commission (CWC) of India, with 42 rivers containing at least two HMs in concentrations above the permissible limit. The aquatic biota inhabiting contaminated sites can accumulate HMs from the surface water. In high concentrations, these HMs can damage biotic components, predominantly by triggering oxidative stress and becoming bioaccumulated in different trophic levels of freshwater ecosystems. Heavy metal contamination in the aquatic environment can also cause direct potential hazards to humans, mostly through their consumption of fish and waterfowl. Thus, it is recommended that the untreated wastewater discharge from industry, agricultural fields, and households be curtail to improve surface-water quality. In this systematic review, we investigated the probable sources of the HMs, the HM contamination in the important rivers and wetlands of India, the effects of HM toxicity on freshwater food chains, and potential remediation measures. The findings of the present study will improve our knowledge about the spectrum of HM toxicity and the effects of HM contamination on the biota in freshwater bodies throughout India, and will also aid policymakers in building strategic and sustainable freshwater management plans around the globe. [ABSTRACT FROM AUTHOR]

Biota in disturbance-prone landscapes have evolved a variety of strategies to persist long term, either locally (resistance) or by regional recolonization (resilience). Habitat fragmentation and isolation can limit the availability of recolonization pathways, and thus the dynamics of post-disturbance community reestablishment. However, empirical studies on how isolation may control the mechanisms that enable community recovery remain scarce. Here, we studied a pristine intermittent stream (Chalone Creek, Pinnacles National Park, California) to understand how isolation (distance from a perennial pool) alters invertebrate community recolonization after drying. We monitored benthic invertebrate reestablishment during the rewetting phase along a ~2-km gradient of isolation, using mesh traps that selected for specific recolonization pathways (i.e., drift, flying, swimming/crawling, and vertical migration from the hyporheic). We collected daily emigration samples, surveyed the reestablished benthic community after 6 weeks, and compared assemblages across trap types and sites. We found that isolation mediated migration dynamics by delaying peak vertical migration from the hyporheic by ca. 1 day on average per 250 m of dry streambed. The relative importance of reestablishment mechanisms varied longitudinally-with more resistance strategists (up to 99.3% of encountered individuals) in the upstream reaches, and increased drift and aerial dispersers in the more fragmented habitats (up to 17.2% and 18%, respectively). Resistance strategists persisting in the hyporheic dominated overall (88.2% of individuals, ranging 52.9%-99.3% across sites), but notably most of these organisms subsequently outmigrated downstream (85.6% on average, ranging 52.1%-96% across sites). Thus, contrary to conventional wisdom, resistance strategists largely contributed to downstream resilience as well as to local community recovery. Finally, increased isolation was associated with a general decrease in benthic invertebrate diversity, and up to a 3-fold increase in the relative abundance of drought-resistant stoneflies. Our results advance the notion that understanding spatial context is key to predicting post-disturbance community dynamics. Considering the interaction between disturbance and fragmentation may help inform conservation in ecosystems that are subject to novel environmental regimes.

Evolutionary innovations, defined as character states that transcend clade norms, are often studied in an exclusively phylogenetic context, but their distribution in time and space indicates that geography also influences the evolution of new ecological, morphological, and physiological traits. In an analysis of 99 fossillzable, norm-breaking innovations in tropical marine Neogene molluscan clades that arose uniquely in either (but not in both) the Indo-West Pacific (IWP) or Atlantic-East Pacific (AEP) realms, I show that there are far more innovations in the IWP (79%) than those in the AEP (21%). Most of the innovations are interpretable as defensive or competitive adaptations or as indicators of extreme habitat specialization. Although the innovations arose in taxonomically rich biotas, only 9% are associated with subclades comprising 10 or more species each, indicating that they contributed little to overall taxonomic richness. Compilations of extant species in 30 pantropical molluscan clades show that the IWP accounts for 71% of tropical shallow-water species, implying that the per-species incidence of norm-breaking innovations is higher there than in the AEP. Only 5% of innovations became extinct in the IWP as compared with 38% in the AEP, mirroring a similar difference in the magnitudes of Late Miocene and later taxonomic extinction in the two realms. These data imply that large-scale disruption strongly limits norm-breaking innovation. Opportunities for adaptive innovation are therefore likely to be few in today's heavily overexploited and disturbed biosphere.

Abstract Plastics are persistent in the environment and may be ingested by organisms where they may cause physical harm or release plastic additives. Monitoring is a crucial mechanism to assess the risk of plastics to the marine and terrestrial ecosystem. Unfortunately, due to unharmonised procedures, it remains difficult to compare the results of different studies. This publication, as part of the Horizon project EUROqCHARM, aims to identify the properties of the available analytical processes and methods for the determination of plastics in biota. Based on a systematic review, reproducible analytical pipelines were examined and the technological readiness levels were assessed so that these methods may eventually (if not already) be incorporated into (harmonised) monitoring programs where biota are identified as indicators of plastic pollution.

As the United Nations develops a post-2020 global biodiversity framework for the Convention on Biological Diversity, attention is focusing on how new goals and targets for ecosystem conservation might serve its vision of 'living in harmony with nature'1,2. Advancing dual imperatives to conserve biodiversity and sustain ecosystem services requires reliable and resilient generalizations and predictions about ecosystem responses to environmental change and management3. Ecosystems vary in their biota4, service provision5 and relative exposure to risks6, yet there is no globally consistent classification of ecosystems that reflects functional responses to change and management. This hampers progress on developing conservation targets and sustainability goals. Here we present the International Union for Conservation of Nature (IUCN) Global Ecosystem Typology, a conceptually robust, scalable, spatially explicit approach for generalizations and predictions about functions, biota, risks and management remedies across the entire biosphere. The outcome of a major cross-disciplinary collaboration, this novel framework places all of Earth's ecosystems into a unifying theoretical context to guide the transformation of ecosystem policy and management from global to local scales. This new information infrastructure will support knowledge transfer for ecosystem-specific management and restoration, globally standardized ecosystem risk assessments, natural capital accounting and progress on the post-2020 global biodiversity framework.

Time series of contaminants in the Arctic are an important instrument to detect emerging issues and to monitor the effectiveness of chemicals regulation, based on the assumption of a direct reflection of changes in primary emissions. Climate change has the potential to influence these time trends, through direct physical and chemical processes and/or changes in ecosystems. This study was part of an assessment of the Arctic Monitoring and Assessment Programme (AMAP), analysing potential links between changes in climate-related physical and biological variables and time trends of persistent organic pollutants (POPs) in Arctic biota, with some additional information from the Antarctic. Several correlative relationships were identified between POP temporal trends in freshwater and marine biota and physical climate parameters such as oscillation indices, sea-ice coverage, temperature and precipitation, although the mechanisms behind these observations remain poorly understood. Biological data indicate changes in the diet and trophic level of some species, especially seabirds and polar bears, with consequences for their POP exposure. Studies from the Antarctic highlight increased POP availability after iceberg calving. Including physical and/or biological parameters in the POP time trend analysis has led to small deviations in some declining trends, but did generally not change the overall direction of the trend. In addition, regional and temporary perturbations occurred. Effects on POP time trends appear to have been more pronounced in recent years and to show time lags, suggesting that climate-related effects on the long time series might be gaining importance.

Plastics are persistent in the environment and may be ingested by organisms where they may cause physical harm or release plastic additives. Monitoring is a crucial mechanism to assess the risk of plastics to the marine and terrestrial ecosystem. Unfortunately, due to unharmonised procedures, it remains difficult to compare the results of different studies. This publication, as part of the Horizon project EUROqCHARM, aims to identify the properties of the available analytical processes and methods for the determination of plastics in biota. Based on a systematic review, reproducible analytical pipelines were examined and the technological readiness levels were assessed so that these methods may eventually (if not already) be incorporated into (harmonised) monitoring programs where biota are identified as indicators of plastic pollution. [ABSTRACT FROM AUTHOR]

We discuss geological and biotic aspects of the extensive Akchagylian transgression that occurred in the Caspian region of Eurasia near the Plio-Pleistocene transition, in Piacenzian and Gelasian. It is shown that the onset of the Akchagylian marine sedimentation in Western Turkmenistan (ca. 3.2 Ma) preceded that in the Kura Basin (ca. 3.0 Ma). The position of the upper boundary of the Akchagylian remains uncertain (ca. 2.1 or 1.8 Ma). The analyzed biotic content of the Akchagylian includes molluscs, microfossils (pollen, dinocysts, foraminifers), and mammals. It is noted that specific forms of the Akchagylian aquatic biota co-occur with microfossils that clearly indicate a connection with the World Ocean or related seas. The palynology of the Akchagylian time signals a directed cooling in the Pliocene and Early Pleistocene with several warm and humid epochs. The Akchagylian transgression was preceded by a change of a structural-sedimentary pattern of the region. In the latest Miocene and Early Pliocene, a pre-existed longitudinal tectonic zonation of the Caucasian-Caspian segment of the Paratethys gradually changed into clearly transverse tectonic zonation. The latter was manifested in the tectonic uplift of the Greater Caucasus, its northern piedmonts and the Lesser Caucasus, and in the subsidence of the western parts of the South and Middle Caspian basins. The interplay of longitudinal and transverse tectonic features shaped the configuration of the Akchagylian brackish-water basin and controlled thickness of its deposits. It was the transverse zonation that dominated in the thickness pattern. The increasing role of the transverse zonation in the post-Akchagylian time is manifested in the magnitudes and rates of the Quaternary tectonic uplift. These parameters were calculated based on current heights of the top of the Akchagylian marine deposits in different parts of the basin. The highest magnitudes of uplift are found in the Eastern Caucasus (up to 1980 m on the NE slope and about 2500 m in the axial part) and in the west of the Lesser Caucasus in eastern Turkey (up to 1750 m). The maximum level of the Akchagylian transgression is estimated at 40–50 m above the present level of the World Ocean. We show a low probability of connection of the Akchagylian basin with the Mediterranean Sea or the Persian Gulf, and a high probability of its connection with the Arctic Ocean through the northern tributaries of the Kama River and the Pechora Basin in the NE of East European Plain. [ABSTRACT FROM AUTHOR]

Introduction: The Sierra Santa Teresa is located 20 km southeast of Hermosillo in the central region of Sonora state, Mexico. The sedimentary strata mainly correspond to limestone, mudstone, wackestone and packstone texture, from the upper Paleozoic. The biota is represented by crinoids of the morphospecies Baryschyr anosus, Cyclocaudex insaturatus, Floricyclus angustimargo, Cyclocion distictus, Lamprosterigma erathense, Preptopremnum rugosum in association with algae, fusulinid foraminifera, coralline sponges (Chaetetes sp.), solitary corals (Lophophyllidium sp., Fomichevella sp.), fenestellid bryozoans (Archimedes stoyanowi), and brachiopods (Antiquatonia sp.). Objective: The principal aim of this study is to analyze the biotic composition in the Sierra Santa Teresa and its paleoecological and paleogeographical considerations. Methods: In this study we synthetize information about the principal taxa collected in outcrops of the Carboniferous of the Sierra, Santa Teresa. Results: The distribution of the biota, and particularly the crinoid morphospecies, allowed paleobiogeographical correlations to be made with other Mississippian-Pennsylvanian localities of Mexico and different regions of the United States of America in Texas, Colorado, Illinois and Oklahoma, which were located in the southwestern of the North American Craton. Conclusions: It is considered that the paleoenvironment inferred based on the paleontological records of the Sierra Santa Teresa were shallow seas that allowed the development of communities of crinoids, as well as other invertebrates such as coralline sponges, solitary corals, fenestellid bryozoans and brachiopods, with a range stratigraphic from the Middle-Upper Mississippian (Chesterian) to the Middle Pennsylvanian (Desmoinesian). [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFAS) have been detected in soils worldwide, suggesting that soil serves as a substantial reservoir for these compounds. This paper provides a comprehensive overview of the origin of PFAS contamination in soil and sediment, as well as the environmental impacts associated with the distribution of PFAS in these mediums. In this review, we also discuss the effects of PFAS on soil microbes, plants, the terrestrial food web, sediment microbes, and benthic microorganisms. The highest concentration of PFAS was found in soils exposed to aqueous film-forming foam (AFFF), the PFAS manufacturing plants, and biosolids, compared to landfills, atmospheric deposition, and industrial discharge, which are the other three sources. Exposure to PFAS has demonstrated negative effects on the richness, diversity, and population structure of bacterial species. It has been observed to interfere with the regular functioning of soil microorganisms, microbes, and benthic organisms in sediment. Nevertheless, the current data is insufficient to grasp the complete spectrum of effects comprehensively. Moreover, the accumulation of PFAS in plants, vegetables, and earthworms is a cause for concern, as they can eventually enter the food chain through trophic transfer processes. Finally, we discuss the challenges and possible strategies that can be implemented to restrict the dispersion of PFAS in sediments and soil.

Microplastics are small plastic materials often defined as those between 5 mm and 0.05 mm in size. Microplastics can have toxicological impacts on various biota, from gut blockages to the transport or leaching of toxicants used in their production or absorbed from the surrounding environment. Although microplastic research has increased significantly, microplastic research in Africa lags behind that of developed countries. South Africa is the African nation with the highest number of microplastic publications. We aimed to determine the current state of microplastic research in South Africa. A total of 46 publications on microplastics in South Africa have been produced. However, many of these publications use methods that might not be accurate in determining holistic descriptions of microplastics in the aquatic environment. Similarly, many ecologically relevant environments and species have not been investigated for microplastics in the country, including any atmospheric or terrestrial environment. We conclude that, although the research being produced in South Africa can be considered adequate, a singular standard method for sampling and assessing microplastics in South African environments is required. The production of such a standard method would be critical to use as a monitoring tool to determine and compare microplastic abundances across the country and globally. Significance: • More than 40 publications on microplastics have been produced in South Africa. • Microplastics have been discovered in multiple aquatic environments in South Africa, but have not been investigated in atmospheric or terrestrial environments. • Polymer analysis was limited in published research. • A standard method is required for comparing between studies. • Terrestrial and atmospheric microplastic studies are required.

This research analyzes data on the microplastic (MP) contamination in the environmental systems (atmosphere, lithosphere, hydrosphere) and the levels of MPs in freshwater of cities with different levels of national income. This study investigates the influencing factors of MP generation, i.e., mismanaged plastic waste, untreated wastewater, number of registered motor vehicles, and stormwater runoff. The statistical correlations between the MP contamination in urban freshwater and the four influencing factors of MP generation are determined by linear regression. The results indicate that MPs are most abundant in aquatic systems (i.e., hydrosphere) and pose a serious threat to the human food chain. The regression analysis shows a strong correlation between mismanaged plastic waste and microfragment smaller than 300 μm in particle size in urban freshwater with high goodness-of-fit (R2 = 0.8091). A strong relationship with high goodness-of-fit also exists between untreated wastewater and microfragment of 1000–5000 μm in particle size (R2 = 0.9522). The key to mitigate the MP contamination in urban freshwater is to replace improper plastic waste management and wastewater treatment with proper management practices.

The potential for forecasting the dynamics of ecological systems is currently unclear, with contrasting opinions regarding its feasibility due to ecological complexity. To investigate forecast skill within and across systems, we monitored a microbial system exposed to either constant or fluctuating temperatures in a 5-month-long laboratory experiment. We tested how forecasting of species abundances depends on the number and strength of interactions and on model size (number of predictors). We also tested how greater system complexity (i.e. the fluctuating temperatures) impacted these relations. We found that the more interactions a species had, the weaker these interactions were and the better its abundance was predicted. Forecast skill increased with model size. Greater system complexity decreased forecast skill for three out of eight species. These insights into how abundance prediction depends on the connectedness of the species within the system and on overall system complexity could improve species forecasting and monitoring.

Monitoring mercury (Hg) levels in biota is considered an important objective for the effectiveness evaluation of the Minamata Convention. While many studies have characterized Hg levels in organisms at multiple spatiotemporal scales, concentration analyses alone often cannot provide sufficient information on the Hg exposure sources and internal processes occurring within biota. Here, we review the decadal scientific progress of using Hg isotopes to understand internal processes that modify the speciation, transport, and fate of Hg within biota. Mercury stable isotopes have emerged as a powerful tool for assessing Hg sources and biogeochemical processes in natural environments. A better understanding of the tissue location and internal mechanisms leading to Hg isotope change is key to assessing its use for biomonitoring. We synthesize the current understanding and uncertainties of internal processes leading to Hg isotope fractionation in a variety of biota, in a sequence of better to less studied organisms (i.e., birds, marine mammals, humans, fish, plankton, and invertebrates). This review discusses the opportunities and challenges of using certain forms of biota for Hg source monitoring and the need to further elucidate the physiological mechanisms that control the accumulation, distribution, and toxicity of Hg in biota by coupling new techniques with Hg stable isotopes.

For species primarily regulated by a common predator, the P* rule of Holt & Lawton (Holt & Lawton, 1993. Am. Nat. 142, 623-645. (doi:10.1086/285561)) predicts that the prey species that supports the highest mean predator density (P*) excludes the other prey species. This prediction is re-examined in the presence of temporal fluctuations in the vital rates of the interacting species including predator attack rates. When the fluctuations in predator attack rates are temporally uncorrelated, the P* rule still holds even when the other vital rates are temporally auto-correlated. However, when temporal auto-correlations in attack rates are positive but not too strong, the prey species can coexist due to the emergence of a positive covariance between predator density and prey vulnerability. This coexistence mechanism is similar to the storage effect for species regulated by a common resource. Negative or strongly positive auto-correlations in attack rates generate a negative covariance between predator density and prey vulnerability and a stochastic priority effect can emerge: with non-zero probability either prey species is excluded. These results highlight how temporally auto-correlated species' interaction rates impact the structure and dynamics of ecological communities.

The contamination of natural ecosystems with heavy metals and metalloids (HMMs) primarily results from anthropogenic activities. Consequently, ongoing efforts are dedicated to the development of technologies aimed at restraining the mobility of HMMs and expediting chemical reactions that convert pollutants from mobile to immobile states. Addressing the reclamation issue always necessitates the selection of the most promising and effective type of reclamation work, as well as justification of land prioritization for reclamation purposes. In terms of performance and future potential, the sorbent-oriented approach, grounded in the concept of “green” utilization of man-made waste as a raw material for creating novel composite sorbents, is gaining traction for land reclamation in disturbed areas. In international practice, diverse environmental risk assessment methods are employed to substantiate the necessity for and prioritize reclamation efforts. The aim of the present study is to evaluate established conventional methods for assessing the risks associated with environmental harm. Additionally, this research aims to assess the efficacy and ecological compatibility of the composite sorbents developed by the author. This evaluation will be conducted by assessing and comparing the levels of potential environmental risks or risks of environmental damage subsequent to the application of these sorbents. The objectives of this study are as follows: 1) to explore the theoretical aspects of HMMs: including the formulation of a definition, investigation onto the origins of HMMs, examination of HMMs’ toxicity, and identification of prevalent methods for evaluating the environmental risks associated with HMMs; 2) to evaluate the effectiveness of established methods for assessing the environmental risks posed by HMMs; 3) to assess the efficacy and environmental sustainability of the composite sorbents developed by the author. This evaluation will involve an examination and comparison of the levels of potential environmental risks and the risks of environmental damage subsequent to the a pplication of these sorbents. The research subject: the mining allotment within the Levikhinskoye mine (classified as an environmental disaster site) is investigated as a disturbed land ecosystem, encompassing industrial waste dumps containing HMMs. The research hypothesis aims to establish the viability of “green” waste utilization from industrial sources as a raw material for composite sorbents used in land reclamation, without escalating the environmental damage. The conducted experiments revealed that sorbents composed of peat/water treatment sludge (at a ratio of 20/80 wt. % with natural moisture content) and peat/diatomite/water treatment sludge (at a ratio of 5/15/80 wt. % with natural moisture content) exhibited the highest level of performance, surpassing an overall efficiency of 89%. A sorbent composed of peat/diatomite (at a ratio of 25/75 wt. % with natural moisture content) demonstrated an overall efficiency of 67.7%. The estimated environmental risks (ER and ED) after the application of the proprietary composite sorbents, which include water treatment sludge, exhibited an average reduction of 89.5% and 88%, respectively.

Based on the monitoring data and calculation of the integral indicator of pollution in the components of the natural environment, the radioecological situation was analyzed in the observation area of Mayak Production Association, FSUE (Federal State Unitary Enterprise), including the territory of the East Ural radioactive trace. The control levels of radionuclides in atmospheric air, soil, and surface waters were assessed on the basis of environmental criteria, taking into account the specifics of radioactive contamination of the territory in accordance with the Recommendations of Roshydromet. To assess the control levels of radionuclides in the components of the natural environment, elk (Alces alces) was identified as a critical organism of the terrestrial biota, and the bottom fish common carp (Cyprinus carpio) was identified as critical in the aquatic biota. The long-term dynamics of the integral indicator of pollution with technogenic radionuclides (90Sr, 137Cs, 239Pu) in the components of the natural environment are presented. The analysis of the radiation situation did not reveal an excess of the environmentally safe level of biota irradiation for the integral indicator of pollution of the components of the natural environment in the observation area of the enterprise. For a modern assessment of the radioecological situation in the area of the location of the Mayak Production Association FSUE, it is necessary to take into account the radioactive contamination of the territory associated with the past activities of the enterprise. [ABSTRACT FROM AUTHOR]

A dynamic mathematical model of the accumulation of radionuclides in the marine biota of Stepovoi Bay was carried out for the scenario of a hypothetical accident with a spontaneous chain reaction with a submerged K-27 submarine. The dynamic model MARINA II was used to calculate the transfer of radionuclides with water masses and the transition to the bottom sediments of the bay. The modeling results were applied to calculate the dynamics of the radiation dose rate for the marine biota of Stepovoi Bay and to assess the environmental risk for the hypothetical accident scenario considered. The predicted radioactive contamination of water is determined mainly by 137Cs and 90Sr, and contamination of bottom sediments, by 137Cs, 90Sr, and 151Sm. The averaged contamination of sediments by 137Cs in this scenario is predicted at a level that is significantly lower than the criterion for attribution to solid radioactive waste. Model assessments have shown that the maximum levels of accidental 137Cs and 90Sr in the fish of Stepovoi Bay was reached one year after a single release, and it does not exceed the established hygienic standards. The highest risk index in the accident scenario considered was estimated for a marine mammal (provided that the animal is permanently located in the bay) and amounted to 0.07. Negative radiation effects are not expected to occur for the ecosystem of StepovoI Bay at this level of environmental risk. The obtained value of the generalized indicator of radioecological safety indicates a weak radiation effect on the ecosystem of the bay for a marine mammal in Stepovoi Bay. [ABSTRACT FROM AUTHOR]

Biodiversity geography is now rapidly successfully developed within general biogeography, encompassing many aspects of biota differentiation on various levels of the biotic cover organization. This study concerns the biodiversity geography from the standpoint of the basic classification of terrestrial ecosystems, utilizing an ecological–geographical approach to interpret their biodiversity; it substantiates regional orobiomes as basic units for assessing the species and ecosystem diversity of mountains. The purpose of this study is to identify the regional specifics of typological diversity of mountain forest ecosystems and biota in connection with the altitudinal-belt structure and altitudinal gradients and to determine their role in the organization of mountain space with respect to its ecotopic structure. To achieve the purpose, statistical methods for processing digital cartographic models of vegetation, relief, and climatic conditions are used. The altitudinal-belt structure of the plant cover was revealed by the example of the Northeast-Transbaikalian taiga orobiome. The spatial structure of the mountain taiga belt, reflecting its typological diversity, was revealed on the basis of a small-scale map of orobiome forests. The mountain taiga belt (with two subbelts) determines the regional specificity of the floristic and cenotic diversity of East Siberian mountain forests of the orobiome. Larch forests predominate in the forest cover of the belt, pine and dark coniferous forests take a limited part, and the species composition decreases along the altitudinal gradient. Along with the features common for the orobiome, there are also specific features of forest biodiversity in its geographical variants associated with different ratios of typological units at different altitudinal levels. The key parameters of heat and moisture supply of high-altitude belts are determined for the mountain taiga belt; they characterize the climatic conditions for the biodiversity formation in the mountains of the Northern Transbaikalia. The successful use of orobiomes in the analysis of biodiversity of the mountain areas determines the prospects for studying forests and for developing a system for their monitoring and protection on a single biome basis. [ABSTRACT FROM AUTHOR]

This paper outlines the nature of microplastic contamination in rivers and the risks to freshwater fishes. We discuss how input sources influence the concentration and composition of microplastics and examine factors that subsequently influence their spatiotemporal dynamics in a river system. We then discuss how the distributions and assemblages of microplastics can impact the risk of interactions with fishes, and the processes associated with the internalisation of microplastic into the body and across the organs and tissues. Finally, we examine the physical and toxicological effects of microplastic exposure in fish species, with special attention directed towards impacts at environmentally relevant concentrations. This review integrates expertise in fluvial geomorphological processes and how they influence the movement and storage of microplastics in river channel environments at a range of scales. We combine this knowledge with expertise in fish ecology and biology to set out a new and integrated analysis of microplastic dynamics in rivers and how these microplastics interact with fish. The integration of knowledge from these fields allows us also to comment upon the microplastic risk to fish and other biota in river environments. [ABSTRACT FROM AUTHOR]

Natural radioactivity is ubiquitous, while the anthropogenic radioactivity is introduced into the environment due to manmade activities. The members of public (MOP) get exposed to both natural and anthropogenic radioactivity through the various routes of intake. The ingestion dose to MOP from natural (40K, 210Po, 226Ra, and 228Ra) and anthropogenic (90Sr and 137Cs) radionuclide through the consumption of benthic and pelagic marine biota collected from Thane creek, Mumbai was investigated. It was observed that 99.9% of ingestion dose is from natural radionuclide while, the anthropogenic radionuclides are contributing just 0.1%. Hence, the dose from anthropogenic radionuclide's due to the consumption of marine biota is negligible compared to that from natural radionuclide's which is also an insignificant contribution in the overall dose exposure to man. [ABSTRACT FROM AUTHOR]

Concentrations of mercury in sediment and benthic invertebrate fauna of Nissum Broad, North-western Jutland, Denmark were investigated. The western coast of Nissum Broad is Harboøre Tange, along which heavy mercury contamination - caused by discharge from production of mercury containing seed dressers in the 1950 and 1960s – was documented in the 1980s. Recent investigations showed marked decreases in mercury contamination in the near shore sediments along Harboøre Tange since the 1980s and the present investigation was initiated to learn if the loss of mercury from Harboøre Tange had led to an increased mercury contamination in the neighbouring marine area, Nissum Broad. Mercury concentrations in the surface sediment correlated with the content of organic matter and the slope of the regression is a good indicator for the degree of mercury contamination. Average mercury concentrations in the upper 5 cm of the sediments ranged between 0.9 and 71 ng g− 1 dry weight (dw) with only 1 station exceeding the Background Assessment Concentration of 70 ng g− 1 dw. Average mercury concentrations in blue mussels Mytilus edulis (169–260 ng g− 1 dw) and periwinkles Littorina littorea (66–203 ng g− 1 dw) exceeded those in uncontaminated areas and the Environmental Quality Standard of approximately 100 ng g− 1 dw. Present sediment mercury concentrations in Nissum Broad are approximately half of what they were in the 1980s, rendering it unlikely that mercury lost from Harboøre Tange has been deposited there. Sediment and organism concentrations did not show any correlation. [ABSTRACT FROM AUTHOR]

We carried out measurements of the CO2 system parameters to evaluate the impact of carbonate and nutrients’ chemistry on phytoplankton populations in the Gulf of Guinea (GoG). The seasonal variations of the CO2 system parameters (fCO2, DIC, pH and TA) along with nitrates and phosphates were quantified weekly at surface (between 0 and 5 m depth) (5.57°N - 4.57°W) in the GoG from May to December 2020. Seawater pH varied widely during the study period, ranging between 8.10-8.35 pH units; DIC and TA varied between 1810 and 2094 μmol kg-1, and between 2051 and 2216 μmol-1 respectively. DIC peaks coincided with the high upwelling period (August and September). For phytoplankton, a total of 60 species were found belonging to four taxonomic phyla: Bacillariophyta, Dinophyta, Chlorophyta and Dictyochophyta. The highest number of phytoplanktonic species were recorded for Bacillariophyta phylum with 36 species (60%). The phylum Dinophyta comprised 22 taxa (36%) and Chlorophyta and Dictyochophyta recorded only one species (2%). The highest specific diversities were observed in August and September with 29 and 26 taxa respectively and the lowest was found in October-November (5 taxa) and December (one taxa). Bacillariophyta and Dinophyta appeared throughout the entire study period. The only species for Chlorophyta phylum appeared in June and July and the Dictyochophyta’s one in May, July and August. In general, the physical (SST, SSS) and chemical (TA, DIC, pH) parameters influenced less than 50% of the phytoplankton population in the coastal area of the GoG. Our study shows that Bacillariophyta population grows up when the physicochemical parameters’ variability increase.

Microplastics pollution of water bodies and drinking water is a relevant problem caused by wide use of plastics in multiple industries, agriculture, manufacturing of household chemicals and medicines. Microplastics pose a threat for human health both due to physical effects and chemicals in their structure as well as microorganisms that can occur on their surface. Some foreign studies describe how microplastics are formed and how they can occur both in marine and fresh water. There are also studies confirming microplastics to be present in seas and rivers in the Russian Federation. Studies that address microplastics in tissues of water organisms are scarce. According to some foreign authors, micro-plastics can be absorbed by mollusks, starfish, actiniae, crabs, etc. Russian researchers provide evidence of considerable quantities of microplastics found in the digestive spruce fish caught in the Tom River. Several foreign studies have established effects produced by microplastics on reproduction, eating behavior as well as declining survivability in crustaceans and fish. Fish products are a well-known significant source of microplastics in human diets. Microplastics bioaccumulation in aquatic biota is considered a potential health threat for organisms at higher trophic levels, including humans at the top of the food chain. Unified water sampling techniques are absent; studies that address effects of microplastics on the human body are scarce; there is no available methodology for hygienic standardization of microplastics in water. All this makes it necessary to have some research aimed at identifying sources and causes of microplastics pollution in water bodies including sources of drinking water supply, to assess public health risks, and to provide safe conditions for water use.

Knowledge about how the COVID-19 pandemic can affect aquatic wildlife is still extremely limited, and no effect of SARS-CoV-2 or its structural constituents on invertebrate models has been reported so far. Thus, we investigated the presence of the 2019-new coronavirus in different urban wastewater samples and, later, evaluated the behavioral and biochemical effects of the exposure of Culex quinquefasciatus larvae to two SARS-CoV-2 spike protein peptides (PSPD-2002 and PSPD-2003) synthesized in our laboratory. Initially, our results show the contamination of wastewater by the new coronavirus, via RT-qPCR on the viral N1 gene. On the other hand, our study shows that short-term exposure (48 h) to a low concentration (40 μg/L) of the synthesized peptides induced changes in the locomotor and the olfactory-driven behavior of the C. quinquefascitus larvae, which were associated with increased production of ROS and AChE activity (cholinesterase effect). To our knowledge, this is the first study that reports the indirect effects of the COVID-19 pandemic on the larval phase of a freshwater invertebrate species. The results raise concerns at the ecological level where the observed biological effects may lead to drastic consequences.

Biodiversity accumulates hierarchically by means of ecological and evolutionary processes and feedbacks. Within ecological communities drift, dispersal, speciation, and selection operate simultaneously to shape patterns of biodiversity. Reconciling the relative importance of these is hindered by current models and inference methods, which tend to focus on a subset of processes and their resulting predictions. Here we introduce massive ecoevolutionary synthesis simulations (MESS), a unified mechanistic model of community assembly, rooted in classic island biogeography theory, which makes temporally explicit joint predictions across three biodiversity data axes: (i) species richness and abundances, (ii) population genetic diversities, and (iii) trait variation in a phylogenetic context. Using simulations we demonstrate that each data axis captures information at different timescales, and that integrating these axes enables discriminating among previously unidentifiable community assembly models. MESS is unique in generating predictions of community-scale genetic diversity, and in characterizing joint patterns of genetic diversity, abundance, and trait values. MESS unlocks the full potential for investigation of biodiversity processes using multidimensional community data including a genetic component, such as might be produced by contemporary eDNA or metabarcoding studies. We combine MESS with supervised machine learning to fit the parameters of the model to real data and infer processes underlying how biodiversity accumulates, using communities of tropical trees, arthropods, and gastropods as case studies that span a range of data availability scenarios, and spatial and taxonomic scales.

A collaborative trial involving 16 participants from nine European countries was conducted within the NORMAN network in efforts to harmonise suspect and non-target screening of environmental contaminants in whole fish samples of bream (Abramis brama). Participants were provided with freeze-dried, homogenised fish samples from a contaminated and a reference site, extracts (spiked and non-spiked) and reference sample preparation protocols for liquid chromatography (LC) and gas chromatography (GC) coupled to high resolution mass spectrometry (HRMS). Participants extracted fish samples using their in-house sample preparation method and/or the protocol provided. Participants correctly identified 9–69 % of spiked compounds using LC-HRMS and 20–60 % of spiked compounds using GC-HRMS. From the contaminated site, suspect screening with participants’ own suspect lists led to putative identification of on average ∼145 and ∼20 unique features per participant using LC-HRMS and GC-HRMS, respectively, while non-target screening identified on average ∼42 and ∼56 unique features per participant using LC-HRMS and GC-HRMS, respectively. Within the same sub-group of sample preparation method, only a few features were identified by at least two participants in suspect screening (16 features using LC-HRMS, 0 features using GC-HRMS) and non-target screening (0 features using LC-HRMS, 2 features using GC-HRMS). The compounds identified had log octanol/water partition coefficient (KOW) values from −9.9 to 16 and mass-to-charge ratios (m/z) of 68 to 761 (LC-HRMS and GC-HRMS). A significant linear trend was found between log KOW and m/z for the GC-HRMS data. Overall, these findings indicate that differences in screening results are mainly due to the data analysis workflows used by different participants. Further work is needed to harmonise the results obtained when applying suspect and non-target screening approaches to environmental biota samples.

This paper presents the state of biota of Drenova Reservoir in Bosnia and Herzegovina (B&H) as water quality indicator. The Drenova reservoir has a multiple role: protection of the Vijaka river basin from floods, provision of water for the Prnjavor fishpond, as well as sport fishing. Bearing in mind the multifunctionality of this reservoir, but also the scarcity of data on the biota of this water body, in 2017, research on phytoplankton, zooplankton, macrozoobenthos and ichthyofauna was performed. Based on the obtained results (qualitative and quantitative composition, saprobic index according to Pantle–Buck, Shannon index), it was established that the water of Drenova Reservoir, as far as phytoplankton and zooplankton community is concerned, corresponds to the transition from oligosaprobic to β-mesosaprobic waters while macrozoobenthos and ichthyofauna refer to β-mesosaprobic water. A small number of representatives of phytoplankton (both qualitatively and quantitatively) is noticeable, as well as the absence of species common to this type of aquatic ecosystems in the observed period. The state of macrozoobenthos taxa is expected considering the properties of the substrate of this accumulation. Ichthyocenosis is characterized by a small number of species, but also by a small number of individuals within those species. [ABSTRACT FROM AUTHOR]

There is an emerging concern about the accumulation of MPs in aquatic ecosystems. In this context as compared to the study of marine environment the freshwater environment has not yet been explored. Microplastics have become an emerging hazard to the natural environment and humanity, which can now be frequently found in different aquatic bodies. Due to their pervasive occurrence in the environment, it can impose severely negative impacts on aquatic organisms. Microplastic particles can also associate with other pollutants like metals and different organic pollutants, which further increase their toxicity. Riverine systems are the most important transporters of these materials from terrestrial to marine environments. It is documented that amongst the rivers, Yangtze (China) contributes the highest plastic litter discharge followed by the Indian, Ganges to the marine environment. In India, scanty data are available on MPs contamination in freshwater environs and it was found that more weightage has been given to the marine environment of east and west coastal regions. Therefore, this paper aims at reviewing the existing as well as current research progress on the abundance, distribution, toxicity, and effects of MPs pollution in the riverine ecosystem in India. [ABSTRACT FROM AUTHOR]

This paper outlines the nature of microplastic contamination in rivers and the risks to freshwater fishes. We discuss how input sources influence the concentration and composition of microplastics and examine factors that subsequently influence their spatiotemporal dynamics in a river system. We then discuss how the distributions and assemblages of microplastics can impact the risk of interactions with fishes, and the processes associated with the internalisation of microplastic into the body and across the organs and tissues. Finally, we examine the physical and toxicological effects of microplastic exposure in fish species, with special attention directed towards impacts at environmentally relevant concentrations. This review integrates expertise in fluvial geomorphological processes and how they influence the movement and storage of microplastics in river channel environments at a range of scales. We combine this knowledge with expertise in fish ecology and biology to set out a new and integrated analysis of microplastic dynamics in rivers and how these microplastics interact with fish. The integration of knowledge from these fields allows us also to comment upon the microplastic risk to fish and other biota in river environments.

Context: Microplastics are widespread in aquatic ecosystems and are commonly recorded in water, sediment and a broad spectrum of marine biota. Yet, the extent to which organisms ingest microplastics directly or indirectly by trophic transfer is largely unknown. Aims: This study characterises microplastic abundance across intertidal water, sediment, and marine biota species of different trophic levels, and investigates whether biomagnification occurs. Methods: Water, sediment, molluscs, crustaceans and fish were sampled from a single area in southern Australia. Key results: Microplastics were recorded in 35% of water, 45% of sediment and 39% of biota samples. Plastic load was 0.36 ± 0.08 microplastics g−1 DW for sediment, 0.50 ± 0.17 microplastics L−1 for water, and 0.70 ± 0.25 microplastics individual−1 for biota. Biomagnification was not found, although similarities in plastic characteristics across biota may imply trophic transfer. Most of the microplastics were fibres (97.5%) of blue, black and transparent colour. Spectral analysis (μ-FTIR) indicated that polyester (50%) and polyethylene (42.3%) dominated the polymer compositions. Conclusions: There were no significant differences in microplastic contamination among biota species, with no biomagnification identified. Implications: We provide information on biomagnification of microplastics alongside a still uncommon characterisation of contamination in water, sediment and biota. Plastic pollution is a growing problem, with microplastics commonly found in marine ecosystems. We investigated plastic presence in water, sediment and marine biota in South Australia, to see if biomagnification was occurring. We found plastic in 35% of water, 45% of sediment and 39% of biota species. No biomagnification was identified, although similarities in microplastics across biota suggest trophic transfer. [ABSTRACT FROM AUTHOR]