Stable isotopes are increasingly used to detect and understand the impacts of environmental changes on riverine ecological properties. The δ13C and δ15N signatures of fish with different feeding habits were measured in a large subtropical river to evaluate how fish isotopic niches respond to environmental gradients and human disturbance. From basal resources to fish consumers, the high values of epilithic periphyton (biofilm) δ13C and suspended particulate organic matter δ15N concurrently determined the niche ranges and space (e.g., convex hull area) of fish communities. Along a longitudinal gradient (except in the industrial zone), the number of fish trophic guilds identified by Bayesian ellipses continuously increased; meanwhile, higher trophic diversity and less redundancy were observed near the lower reaches and estuary. Variance inflation factors were estimated to detect the multicollinearity of 40 environmental variables, 14 of which were selected as indicators. Relative importance (RI) analysis was used to evaluate the explanatory power of these indicators for the spatial variation in isotopic niche metrics; the results showed that riffle habitat area, water nitrate concentration, gravel-cobble substrate, and riparian buffer width were the 4 key environmental indicators (average RI > 12%) that determined the longitudinal pattern of fish isotopic niches. These findings suggested that community-level δ13C signatures are more responsive to changes in habitats (e.g., riffle) and substrates (e.g., gravel-cobble) supporting the productivity of autochthonous diatoms while δ15N signatures respond to water quality altered by nitrogen pollution from manure-fertilized farming and poultry livestock effluent. Furthermore, δ15N may be more robust and interpretable than δ13C as an isotopic indicator of ecosystem change in rivers exposed to multiple or complex anthropogenic stressors.This research evaluated the performance of a lab-scale anaerobic membrane bioreactor (AnMBR) treating municipal sewage pre-concentrated by forward osmosis (FO). The organic loading rate (OLR) and sodium concentrations of the synthetic sewage stepwise increased from 0.3 to 2.0 g COD L-1 d-1 and from 0.28 to 2.30 g Na+ L-1 to simulate pre-concentration factors of 1, 2, 5 and 10. No major operational problems were observed during AnMBR operation, with COD removal efficiencies ranging between 90 and 96%. The methane yield progressively increased from 214 ± 79 to 322 ± 60 mL CH4 g-1 COD as the pre-concentration factor increased from 1 to 10. This was mainly attributed to the lower fraction of methane dissolved lost in the permeate at higher OLRs.  https://www.selleckchem.com/products/hc-258.html  Interestingly, at the highest pre-concentration factor (2.30 g Na+ L-1) the difference between the permeate and the digester soluble COD indicated that membrane biofilm also played a role in COD removal. Finally, a preliminary energy and economic analysis showed that, at a pre-concentration factor of 10, the AnMBR temperature could be increased 10 °C and achieve a positive net present value (NPV) of 4 M€ for a newly constructed AnMBR treating 10,000 m3 d-1 of pre-concentrated sewage with an AnMBR lifetime of 20 years.The holiday effect is a useful tool to estimate the impact on air pollution due to changes in human activities. In this study, we assessed the variations in concentrations of fine particulate matter (PM2.5) and nitrogen dioxide (NO2) during the holidays in the heating season from 2014 to 2018 based on daily surface air quality monitoring measurements in Beijing. A Generalized Additive Model (GAM) is used to analyze pollutant concentrations for 34 sites by comprehensively accounting for annual, monthly, and weekly cycles as well as the nonlinear impacts of meteorological factors. A Saturday effect was found in the downtown area, with about 4% decrease in PM2.5 and 3% decrease in NO2 relative to weekdays. On Sundays, the PM2.5 concentrations increased by about 5% whereas there were no clear changes for NO2. In contrast to the small effect of the weekend, there was a strong holiday effect throughout the region with average increases of about 22% in PM2.5 and average reductions of about 11% in NO2 concentrations. There was a clear geographical pattern in the strength of the holiday effect. In rural areas the increase in PM2.5 is related to the proportion of coal and biomass consumption for household heating. In the suburban areas between the Fifth Ring Road and Sixth Ring Road there were larger reductions in NO2 than downtown which might be due to decreased traffic as many people return to their hometown for the holidays. This study provides insights into the pattern of changes in air pollution due to human activities. By quantifying the changes, it also provides insights for improvements in air quality due to control policies implemented in Beijing during the heating season.In order to promote the development of the biogas industry, solutions are needed to improve concrete structures durability in this environment. This multiphysics study aims to analyse the multiphases interactions between the liquid phase of an anaerobic digestion system and cementitious matrices, focusing on (i) the impacts of the binder nature on the anaerobic digestion process at local scale, and (ii) the deterioration mechanisms of the materials. Cementitious pastes made of slag cement (CEM III), innovative metakaolin-based alkali-activated material (MKAA), with compositions presumed to resist chemically aggressive media, and a reference binder, ordinary Portland cement (CEM I), were tested by immersion in inoculated cattle manure in bioreactors for a long period of five digestion cycles. For the first time it was shown that the digestion process was disturbed in the short term by the presence of the materials that increased the pH of the liquid phase and slowed the acids consumption, with much more impact of the MKAA. However, the final total production of biogas was similar in all bioreactors. Material analyses showed that, in this moderately aggressive medium, the biodeterioration of the CEM I and CEM III pastes mainly led to cement matrix leaching (decalcification) and carbonation. MKAA showed a good behaviour with very low degraded depths. In addition, the material was found to have interesting ammonium adsorption properties in the chemical conditions (notably the pH range) of anaerobic digestion.