In the context of the rapid development of the Belt and Road (B&R) Initiative, the continuous transfer of Sino-US trade to the B&R countries is an important means to mitigate the threat of Sino-US trade, and the environmental impact of this transfer should be considered, so as to provide a scientific basis for China’s policy formulation about achieving this possible trade transfer with minimized environmental impacts. This study proposes a multiregional input-output model and analyzes the impact on carbon dioxide (CO₂) emissions of transferring the Sino-US trade to the B&R countries for two types of scenarios. The results show the following: (1) A transfer of either the import trade or the export trade increases global and Chinese CO₂ emissions by 81.76 Mt and 24.84 Mt, respectively. When both the import trade and export trade are transferred, the increases in CO₂ emissions are only 0.22% and 0.26%, respectively. (2) Globally, the changes in international trade-embodied CO₂ emissions are responsible for most of the global emission changes, especially the CO₂ emissions exported from Russia, India, and many Southeast Asian countries to China. (3) Different from the impact on global emissions, the increases in Chinese domestic production-based CO₂ emissions influence China’s total CO₂ emissions. Due to the imported CO₂ emissions, the consumption-based CO₂ emissions are affected to a greater degree and increase by 70.30 Mt, accounting for only 0.86% of the CO₂ emissions in 2015. Finally, some policy implications are proposed.

Green vegetation improvement is an economical strategy to mitigate dust air pollution. The anticipated performance index (API) is considered a main criterion to select the suitable plants of urban forests. API is calculated by taking air pollution tolerance index (APTI) and socio-economic and biological aspects into account. In the present work, API of four current deciduous tree species in urban areas of Iran was evaluated. The seedlings were soil-dusted by a dust simulator in plastic chambers at levels of 0, 300, 750, and 1500 μg/m³ at intervals of 1 week for 70 days. At 750 and 1500 μg/m³ dust concentrations (DCs), greatest dust collection capacity was observed with Morus alba and the lowest one with Melia azedarach. Increasing DC declined APTI of all species. At 750 μg/m³ DC, only Morus was tolerant, but at 1500 μg/m³ DC, this species and Melia were categorized as intermediate, and Celtis caucasica and Fraxinus rotundifolia as sensitive. Morus was assessed as a good performer under two higher DC. Celtis was recognized as a moderate under 750 μg/m³ DC and poor performer under 1500 μg/m³ DC. Thus, Celtis can be considered as a biomonitor for air quality or as sink for dust in high dusty areas because of its high capacity of dust deposition. At two higher DCs, Fraxinus and Melia showed very poor and poor performance; planting these species in high dust areas is not recommended. In contrast, Morus is the most suitable tree species for urban green spaces in dusty regions, due to its high dust collection capacity and high APTI and API values.

Previous studies have indicated that particulate matter 2.5 (PM2.5) exposure stimulates systemic inflammation and activates the hypothalamus–pituitary–adrenal (HPA) axis, both of which are associated with stroke incidence and mortality. However, whether filtered air (FA) intervention modulates inflammation and HPA axis activation is still largely unknown. For FA group and PM2.5 group, adult Sprague-Dawley male and female rats were exposed to FA or PM2.5 for 6 months, respectively. For PM2.5 + 15 days FA group, the rats were achieved by receiving 15 days FA after PM2.5 exposure for 6 months. The immune cells and inflammatory biomarker levels in the blood and brain were analyzed by flow cytometry, ELISA, and qRT-PCR. To assess HPA axis activation, the levels of hormones in the blood were also analyzed by ELISA. FA intervention increased the percentage of CD4 T cells and T cells in the blood, which had decreased after PM2.5 exposure in both male and female rats. The ELISA and qRT-PCR results showed that FA intervention significantly reduced the levels of inflammatory biomarkers in the peripheral blood, and alleviated neuroinflammation in the cortex, hippocampus, and striatum. In addition, FA intervention also inhibited the inflammation in the hypothalamus and pituitary and adrenal glands, and decreased the levels of HPA axis hormones. Our results indicate that FA intervention exerts a protective effect on the brain by decreasing inflammation and HPA axis activation after PM2.5 exposure in both male and female rats.

Environmental objects (surface and groundwater, soil, bottom sediments, wastewater) are reservoirs in which large-scale multidirectional exchange of determinants of antibiotic resistance between clinical strains and natural bacteria takes place. The review discusses the results of studies on antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARG) isolated from environmental objects (water, soil, sewage, permafrost) of the Russian Federation. Despite the relevance of the topic, the number of available publications examining the resistomes of Russian water bodies and soils is small. The most studied environmental objects are surface waters (rivers, lakes), permafrost deposits. Soil resistomes are less studied. Data on ARG and ARB in wastewater are the least covered in publications. In most of the studies, antibiotic resistance of isolated pure bacterial cultures was determined phenotypically. A significant number of publications are devoted to the resistance of natural isolates of Vibrio cholerae, since the lower reaches of the Volga and Don rivers are endemic to cholera. Molecular genetic methods were used in a small number of studies. Geographically, the south of the European part of Russia is the most studied. There are also publications on the distribution of ARG in water bodies of Siberia and the Russian Far East. There are practically no publications on such developed regions of Russia as the center and northwest of the European part of Russia. The territory of the country is very large, anthropogenic and natural factors in its various regions vary significantly; therefore, it seems interesting to combine all available data in one work.

Nitric oxide (NO) and nitrous oxide (N₂O) production in biological nutrient removal has been studied widely due to the strong negative effects on the environment. Nitrite-denitrifying phosphorus removal (N-DPR), as a significant source of NO and N₂O production, has received great attention. However, the mechanism of NO and N₂O production at different phosphorus concentrations is not well understood. Therefore, this study was conducted to investigate the effect of phosphorus concentration on pollutant removal, as well as NO and N₂O production during the N-DPR process. The results showed that the phosphorus removal efficiency was improved with the increase of phosphorus concentration, which is caused by the enrichment of denitrifying phosphorus accumulating organisms (DPAOs) at high phosphorus concentration. High NO production was observed at phosphorus concentration of 0.5 mg L⁻¹, which is mainly attributed to the slow recovery of reductase activity and low abundance of DPAOs. The maximal N₂O accumulation of 31.45 mg L⁻¹ was also achieved at phosphorus concentration of 0.5 mg L⁻¹. The possible reason is that fewer poly-β-hydroxyalkanoates (PHAs) were synthesized by glycogen accumulating organisms (GAOs) at low phosphorus concentration, which could intensify the electron competition among different reductases. In addition, free nitrous acid (FNA) inhibition was another significant reason for high N₂O production.

Excessive nitrogen (N) loading has had severe consequences in coastal zones around the world. Denitrification and anammox are major microbial pathways for removing N in aquatic environments before it is exported to the coast. To assess two processes in eutrophic riverine systems, the denitrification and anammox and their bacterial participants were investigated in sediments of the Xiaoqing (XQ) River and Jiaolai (JL) River in Northeast China. By combining the evidence from N¹⁵ isotope tracing experiment and functional gene-based analysis, it was found that denitrification and anammox are ubiquitous along the investigated riverine sediments. The denitrification varied from 39.38 to 1433.01 nmol N₂ m⁻² h⁻¹. Moreover, the anammox rates were in the range of 15.91 to 1209.97 nmol N₂ m⁻² h⁻¹. Quantitative PCR results revealed that the nirK and nirS genes were in the order of 10⁴–10⁶ copies g⁻¹ and 10³–10⁵ copies g⁻¹, respectively, in both river sediments, while the hzsA was in the order of 10⁶–10⁵ copies g⁻¹ in XQ at approximately two orders of magnitude compared with JL. The phylogenetic analysis of functional genes revealed the high diversity of the denitrifier and low diversity of anammox bacteria. Variance partitioning analyses verified that the grain particle characteristics were the major factor group determined the N removal efficiency. The denitrification and anammox processes were estimated to have removed 16.1% of the inorganic nitrogen inputs before being exported to Laizhou Bay, which highlights that a more extensive understanding of the regularity of the N removal processes is important in the technical remediation of eutrophication problems.

In the absence of adequate molecular oxygen in a continuously flooded soil, other oxidizing anions can potentially oxidize arsenite (As(III)) into arsenate (As(V)) and reduce the bioavailability of arsenic (As) to rice while maintaining high rice yield. We conducted a greenhouse study to evaluate the effect of two prevalent oxyanions (10 mg/L nitrate and/or 50 μg/L perchlorate) on the As uptake, speciation, and accumulation in a hybrid rice (XL753) at the heading and maturity stages. The presence of nitrate and/or perchlorate at the used concentrations increased the rice grain yield by 35–93% to16.6–23.8 g/pot while lowering the total As in rice grains by 34–45% to 0.81–0.97 mg/kg dry weight. Perchlorate alone led to the greatest decrease in total As. Organic As was the predominant species in rice grains, with dimethylarsinic acid (DMA) accounting for 66–76% of total As in all treatments. In contrast, inorganic As was the dominant As form in rice straws and roots, with As(V) accounting for 62.4–91.4% of total As in all treatments. The translocation and accumulation of different As species in rice tissues varied at different growth stages in the presence of two tested oxyanions, as indicated by the ratios of inorganic vs organic As and inorganic As(III) vs As(V). Overall, the presence of oxyanions in irrigation water at the tested concentrations significantly decreased the total As accumulation in rice grains, while enhancing the rice yield.

The original version of this article unfortunately contained an error.

Metsulfuron-methyl is a sulfonylurea herbicide, primarily with postemergence activity but also with occasional pre-emergent activity, used for control of weeds and woody plants on agricultural lands and natural areas. The active ingredient is popular in Alaska as Ally XP formulation; little is known about its high-latitude environmental behavior and potential adverse impacts on soil health in cold regions. Our study determined field degradation rates at two experimental farms in Alaska and assessed whether laboratory-incubated soil amended at 1× or 100× label rates would adversely impact microbial community diversity. DT50 was observed at 4.12–5.13 days, with the compound below 1 μg/kg detection limit at 90 days. Interestingly, this is faster than the reported range of field half-lives in the literature (7–42 days). Microbial community composition was not affected by MSM at both 1× and 100× rates. High-latitude regions exhibit extreme summer photoperiods that may exacerbate the MSM degradation/dissipation rate; we postulate that timing of application may have large impacts on MSM attenuation.

Humic acid (HA) in water is the main precursor of disinfection by-products in the chlorination process of drinking water. In this study, an ultraviolet/persulfate (UV/PS) process, in a laboratory-scale system, is successful in the degradation of HA. The results showed that HA was significantly degraded (UV₂₅₄ removal rate of ~ 89%) and partially mineralized (~ 62.5%) by UV/PS treatment at a PS dose of 0.4 mM, pH of 7.12, and UV irradiation time of 160 min. The trihalomethane formation potential (THMFP) was also significantly reduced (THMFP reduction of ~ 85.4%). A strong linear relationship was observed between UV₂₅₄ and dissolved organic carbon. The removal rate of HA at low pH was better than that at high pH conditions, and the inhibition by Cl⁻ slowed down after an initial increase, and the inhibition was weaker than HCO₃⁻. By analyzing the fluorescence spectrum of two humic-like substances, the fluorescent compounds C1 and C2 in HA were significantly degraded, and the change in C1 and C2 concentration was correlated with the decrease of THMFP. The degradation of different fractions of natural organic matter in real-world water samples indicated that UV/PS has significant potential to decrease HA in water.