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In Chinese reservoirs, however, no environmental factor correlated well with THg contents in zoobenthos, and only DOC concentrations showed positive correlation with MeHg contents in zoobenthos. Besides, the algal dietary was also positively correlated with MeHg contents in zoobenthos. EPA and DHA contents of zoobenthos in Swedish lakes primarily associated with algal diet. By contrast, in Chinese reservoirs, EPA and DHA contents of zoobenthos were affected by both environmental factors and algal diet.Global value chains and climate change have a significant impact on water resources and increasingly threaten freshwater ecosystems. Recent methodological proposals for life cycle impact assessment (LCIA), evaluate water use impacts on freshwater habitats based on river hydraulic parameters alterations. However, they are limited to French rivers due to lack of global data and models. On this basis, this article proposes an approach to compute regionalized characterization factors for modeling river habitat change potential (HCP) induced by water consumption, potentially applicable worldwide. A simplified model is developed for fish guilds and invertebrates. Based on French datasets, it establishes a relationship between HCP and river hydraulic parameters. A methodology to derive discharge and hydraulic geometry at the reach scale is proposed and applied to European and Middle Eastern rivers below 60°N latitude. Regionalized HCPs are calculated at the river reach scale and aggregated at watershed. Then, the impact of agricultural water use in contrasted European and Middle Eastern countries is evaluated comparing the outcomes from the HCP and the Available Water Remaining (AWARE) models at the national scale, considering water supply mix data. The same analysis is carried out on selected river basins. Finally, result consistency, uncertainty and global applicability of the overall approach are discussed. The study demonstrates the reproducibility of the impact model developed for French rivers on any hydrographic network where comparable ecological, hydrological and hydraulic conditions are met. Furthermore, it highlights the need to characterize impacts at a higher spatial resolution in areas where HCP is higher. Large scale quantification of HCP opens the way to the operationalization of mechanistic LCIA models in which the habitat preferences of freshwater species are taken into account to assess the impacts of water consumption on biodiversity.This study involved the monitoring and risk assessment of current-use pesticides in surface water from the northwestern section of the Taihu Lake Basin (China) in 2019. In particular, 114 current-use pesticides were measured in samples collected during four campaigns spread across the wet, dry, and normal seasons. Pesticide concentrations were measured by means of a novel analytical method involving online solid-phase extraction coupled to LC-MS/MS. In total, 1 plant growth regulator, 34 herbicides, 23 insecticides, and 25 fungicides were detected. Detection frequencies greater than 90% were recorded for 26 pesticides; furthermore, acetamiprid, azoxystrobin, bentazone, carbendazim, isoprothiolane, metolachlor, paclobutrazol, and triadimenol were present in every sample. The measured pesticide concentrations varied widely, from below the detection limit to 10,600 ng/L (tricyclazole). The highest median concentrations for the fungicide, herbicide, and insecticide families were observed for carbendazim (135 ng/Liconazole). The integrated consideration of ecological risk and frequency of risk inform priorities for regional pesticide management and control.Fjord systems in higher latitudes are unique coastal water ecosystems that facilitate the study of dissolved organic matter (DOM) dynamics from surface to deeper waters. The current work was undertaken in the Trondheim fjord characterized by North Atlantic waters, and compared DOM fractions from three depths - surface (3 m), intermediate (225 m) and deep (440 m) in four seasons, from late spring to winter in 2017. The high-resolution mass spectrometry data showed that DOM composition varies significantly in different seasons rather than in different depths in the fjord systems. The bacterial community composition was comparable except at spring surface and summer intermediate depths. Bacterial production was minimal below the euphotic layer, even with sufficient availability of inorganic nutrients. [https://www.selleckchem.com/products/pf-04691502.html find more] The bacterial production rate in the surface waters was about 7 times and over 50 times higher than that of the aphotic zone in the winter and the summer seasons, respectively. The surface heterotrophic microbial communities might have rapidly consumed the available labile DOM, with the production of more refractory DOM limiting bacterial production in aphotic layers. The greater number of CRAM-like formulas determined in the surface waters compared to other depths supports our hypothesis. The refractory DOM sequestered in the water column may either be exported into sediments attached to particulate matter and marine gels, or may escape into the atmosphere as carbon dioxide/monoxide during the photochemical oxidation pathways, suggesting that it is involved in climate change scenarios.River Yamuna is one of the major lifelines of Northern India. The study quantified 16 target compounds including pharmaceuticals, personal care products, and hormones in the Yamuna river. Surface water samples were collected from 13 locations spanning 575 km along the river, and from two of its tributaries, Hindon river and Hindon canal. Spatiotemporal variations in the occurrence of the target compounds at the 13 sites during summer and post-monsoon season were investigated. Caffeine, estrone, gemfibrozil, sulfamethoxazole, testosterone and trimethoprim were found in all the samples, indicating substantial usage and/or persistence in the environment. The mean concentration of the target compounds ranged from 25.5 to 2187.5 ng/L. Higher concentrations were detected during the post monsoon, compared to the summer season. The highest concentration detected was of trimethoprim (8807.6 ng/L) during summer sampling, followed by caffeine (6489.9 ng/L) and gemfibrozil (2991 ng/L), during the post-monsoon sampling. The lowest concentration detected was of estrone (10.7 ng/L), during the summer sampling. The runoff from the catchment areas is one of the contributing factors for the increased concentration of the compounds during post monsoon. During summer, the river bed goes dry, facilitating the adsorption of the compounds onto the river bed sediments. The three sampling locations Okhla barrage (ponding of water from drains traversing Delhi), confluence of Yamuna with Shahadara drain (industrial and poultry cluster, and Ghazipur dumping yard) and Agra city (industrial clusters) were the hotspots in terms of total concentration of the target compounds. The study also reported the presence of PPCPs and hormones in the finished drinking water of two DWTPs at Mathura and Agra.Chemodenitrification-the abiotic (chemical) reduction of nitrite (NO2-) by iron (II)-plays an important role in nitrogen cycling due in part to this process serving as a source of nitrous oxide (N2O). Questions remain about the fate of NO2- in the presence of mineral surfaces formed during chemodenitrification, such as iron(III) (hydr) oxides, particularly relative to dissolved iron(II). In this study, stirred-batch kinetic experiments were conducted under anoxic conditions (to mimic iron(III)-reducing conditions) from pH 5.5-8 to investigate NO2- reactivity with goethite (FeOOH(s)) and Fe(II)-treated goethite using wet chemical and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy. Nitrite removal from solution by goethite was more rapid at pH 5.5 than at pH 7 and 8. Spectral changes upon nitrite adsorption imply an inner-sphere surface interaction (monodentate and bidentate) at pH 5.5 based on ATR-FTIR spectra of the nitrite-goethite interface over time. In iron(II)-amended experiments at pH 5.5 with high aqueous Fe(II) in equilibrium with goethite, nitrous oxide was generated, indicating that nitrite removal involved a combination of sorption and reduction processes. The presence of a surface complex resembling protonated nitrite (HONO) with an IR peak near ~1258 cm-1 was observed in goethite-only and iron(II)-goethite experiments, with a greater abundance of this species observed in the latter treatment. These results might help explain gaseous losses of nitrogen where nitrite and iron(II)/goethite coexist, with implications for nutrient cycling and release of atmospheric air pollutants.As the regulations on vehicle emissions have become more stringent internationally and real-driving emissions (RDE) have been established, the on-road characteristics of emissions have gained importance in vehicle research and development. The results of the fuel consumption levels and emissions from on-road tests are affected by many factors, such as driving conditions, routes and environmental conditions. Therefore, more research and analysis are needed for the effects of environmental factors and driving conditions according to RDE phase on the NOx emissions. In this study, RDE tests were conducted by season to analyze the on-road NOx emission characteristics of lean NOx trap (LNT)- and selective catalytic reduction (SCR)-equipped diesel vehicles corresponding to the Euro 6b regulation prior to the application of the RDE regulation. The purpose of this study is to analyze the effects of seasonal factors and phases of the RDE routes on the NOx emission and NOx conversion efficiency of catalyst. In spring/autumn and summer, the engine-out and tail-pipe NOx emissions were higher 1.3-5.9 times for vehicle A and 1.3-28.4 times for vehicle B in the urban phase than in other phases. In the urban phase, the engine bay temperature was probable to rise owing to frequent stops and low-speed driving, leading to a high intake air temperature, which causes excessive NOx emission, particularly in summer. The average air filter temperature in urban phase was 11-15 °C higher than the environment temperature for vehicle A. The NOx conversion efficiency of the LNT was highest at 54.1% on motorway and the efficiency was dependent on the phase of the test route. The NOx conversion efficiency of the SCR, which is dependent on the catalyst temperature, was highest at 98.7% in spring motorway and the efficiency was affected by the combined factors of season and phases.Based on 197 monthly river water and groundwater samples and 30 event-scale precipitation samples, our study reports the distribution of hydrogen and oxygen isotopes and pollution indicators in Min River Basin. The variation of δ18O and d-excess indicate that the water source in the upper main course water is more variable and that in the middle-lower part is relatively stable. Comparison between plots of δ2H versus δ18O in the river water and precipitation reflect the dominant water source is different between river water in the upper and middle-lower parts. The electrical conductivity (EC) shows a similar spatial variation trend for main course water collected in four campaigns. The pollutant concentration change at the confluences of main tributaries shows that the inflow of Heishui River and Dadu River leads to decreased NO3- and Cl-, while that of Xi River, Pu River and Fuhe River leads to a leap in NO3- and Cl-. A significant positive correlation is observed between EC and δ18O, indicating the consistent control of water sources on isotope distribution and water quality.