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Foliar spraying with silicon (Si) and selenium (Se) can regulate the accumulation of cadmium (Cd) in rice ( Oryza sativa L.), but the effects on different cultivars and the main determining factors remain unknown. Field experiments were conducted to investigate the ability of foliar spraying with Si, Se, and mixture of Si and Se to decrease Cd accumulation and translocation in rice cultivars WYHZ, NJ5055, and ZF1Y. All three spray treatments significantly decreased the Cd concentration in WYHZ brown rice, but had no such effect in NJ5055 or ZF1Y, relative to controls. WYHZ had a higher ability to translocate Cd than the other two cultivars. Foliar spraying changed this pattern by decreasing Cd translocation from roots to stems and from stems to brown rice, and increasing Cd translocation from stems to leaves. Foliar spraying also increased the photosynthetic rate, stomatal conductance, and transpiration efficiency in WYHZ. Structural equation modelling revealed the negative effects of photosynthetic rate, transpiration efficiency, and leaf Cd concentration, and the positive effects of stem and root Cd concentration on brown rice Cd concentration. Structural equation modelling further highlighted the significant role of stem Cd concentration in determining brown rice Cd concentration, which had the highest standardized total effects (direct plus indirect effects). These findings demonstrate that foliar spraying with Si and Se is effective in reducing Cd accumulation in rice cultivars with high Cd translocation ability, mainly by reducing stem Cd concentrations and ameliorating plant photosynthetic processes. [ABSTRACT FROM AUTHOR]

Copper (Cu) smelting released large amounts of Cu and contaminated the environment. However, few studies have investigated the Cu exposure risks for people located near Cu smelters. In this study, atmospheric bulk deposition, food from local families, drinking water and biological samples (hair and urine) were collected in three villages near the largest flash Cu smelter in China. The objective of the current study was to investigate how non-ferrous metals smelting affect the human health. Total atmospheric Cu depositions (56–767 μg m −2 yr −1 ) were one or two orders of magnitude greater than that of unpolluted rural areas. The Cu concentrations in locally grown vegetables and dietary chronic daily intake (CDI) of local residents showed a consistently decreasing trend with atmospheric Cu depositions. Dietary intake of vegetables and rice were the two major pathways of total CDI, which accounted for >93% totally. The Cu exposure showed higher potential non-carcinogenic risk to human health of local residents, especially children living around the Cu smelter through food consumptions. Health impact monitoring data revealed that mean Cu concentrations in hair and urine samples were ranged from 5.13 to 28.85 mg kg −1 and 19.90 to 54.61 μg L −1 in the three villages, respectively. Significant correlation between hair Cu concentrations and the CDI of Cu indicated food ingestion had adverse effects on the health of the local residents. The result suggested that nonferrous metal smelter should be away from residential area and locally produced crops became unsuitable for consumption. Therefore, effective measures on Cu pollution management and control in the surrounding area should be formulated and implemented. [ABSTRACT FROM AUTHOR]

Anthropogenic metals adsorbed on suspended fine particles can be deposited on remote and inaccessible high mountains by long-range atmospheric transport. In this study, we investigated the cadmium (Cd) and lead (Pb) in the soils, mosses and rainfall of three transects on the Gongga Mountain, eastern Tibetan Plateau, to understand the mountain interception effects on their atmospheric transport. The concentrations of Cd and Pb in the soils and mosses displayed a pattern of eastern transect > northern transect > western transect. The distribution of Cd and Pb on the eastern transect increased from 2000 to 2900 m a.s.l. (above sea level), decreased toward the timberline, and increased again with altitude; on the northern transect, it generally decreased with altitude whereas a distribution trend was not clearly observed on the western transect. The Cd and Pb concentrations in the rainfall of the eastern transect generally decreased with altitude, and they were higher inside forests than outside forests and temporally higher in the winter than the summer. The Pb isotopic ratios coupled with moss bio-monitoring distinguished anthropogenic sources of Cd and Pb on the eastern and northern transects, whereas bedrock weathering was the main source of Cd and Pb on the western transect. We proposed a conceptual model to delineate the effects of terrain, local climate and vegetation on the transport of atmospheric metals. Our results highlighted the high mountains in the eastern Tibetan Plateau as an effective natural barrier limiting atmospheric metal transport. [ABSTRACT FROM AUTHOR]

A comprehensive survey was conducted to Masson pine ( Pinus massoniana L.) needles widely distributed in Shanghai in order to investigate the levels and homologue group patterns of short- and medium-chain chlorinated paraffins (SCCPs and MCCPs), to identify and quantitatively assess source contributions to the total CPs in pine needle samples. The concentration ranged from not detected (ND) to 13,600 ng g − 1 with a geometric mean (GM) value of 63.7 ng g − 1 for ΣSCCPs, from 12.4 to 33,500 ng g − 1 with a GM value of 677 ng g − 1 for ΣMCCPs, and from 14.0 to 45,700 ng g − 1 with a GM value of 768 ng g − 1 for total CPs. For different sampling units, the pollution levels both for SCCPs and MCCPs in pine needles were in the same orders: Pudong > suburbs > Puxi > Chongming. These significant differences in SCCPs and MCCPs among four sampling units could be associated with difference in industrial activities and to some extent also in population density. All pine needle samples ( n = 131) were divided into 2 groups by hierarchical cluster analysis (HCA) for SCCPs and MCCPs, the most abundant homologue groups in the bulk of pine needle samples were C 11 Cl 5 − 7 and C 13 Cl 5 − 7 for SCCPs, and C 14 Cl 7 − 8 and C 15 Cl 7 − 8 for MCCPs. Correlation analysis suggested that SCCPs and MCCPs in pine needles in the studied area may be derived from different sources. Four sources for pine needles were identified by the FA-MLR model; their relative contributions to the total CP burden in pine needles were 18.0% for F1 (attributed to commercial SCCP mixture), 42.2% for F2 (attributed to commercial MCCP mixture), 29.3% for F3 (attributed to LRAT), and 10.5% for F4 (unknown source). CP contamination of atmospheric air by point sources and long-range atmospheric transport in Shanghai should receive more attention by local government. [ABSTRACT FROM AUTHOR]

The dynamic behavior of 24 dissolved pharmaceuticals over tidal cycles in the Yangtze Estuary, China was studied to assess the tidal impact on the fate of pharmaceutical residues. The results show that most pharmaceuticals were frequently detected with concentrations from below detection to 27.2 ng/L, with sulfamethoxazole, sulfamethazine, erythromycin, thiamphenicol and florfenicol dominating. During tidal cycles, pharmaceutical concentrations decreased during tidal rise, then increasing during tidal receding for all locations, except at site S2 which showed an opposite trend due to unique water movement there. It was observed that most compounds showed a non-conservative behavior, while diazepam and sulfamethoxazole displayed a conservative behavior. The pharmaceutical concentrations were found to increase with dissolved organic carbon (DOC) concentration, suggesting DOC as a carrier of pharmaceuticals. In addition, many compounds showed a significant negative relationship with suspended particulate matter (SPM) concentration, indicating SPM–water interactions as a control of pharmaceutical behavior in estuarine environment. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) contamination from mining and smelting operations has led to growing environmental health concerns. In this study, soil, surface water, drinking water, rice, vegetables, and biomarkers (hair and urine) were collected from local residents near an active lead-zinc mine and a copper smelter. The aim was to determine how nonferrous metal mining and smelting activities have affected the health of local residents. It was found that the Cd concentrations in most soil and rice samples exceeded the national tolerance limits of China. Dietary intakes of rice and vegetables were the two major pathways of Cd exposure to local residents, accounting for >97% of the total probable daily intake. The excessive daily intake of Cd resulted in potential non-carcinogenic risks to the local residents, especially to children living around the two areas. The mean hair and urine Cd concentrations were 0.098 ± 0.10 mg kg−1 and 5.7 ± 3.1 μg L−1 in the mining area, and 0.30 ± 0.21 mg kg−1 and 5.5 ± 3.5 μg L−1 in the smelting area, respectively. A significantly positive correlation between hair Cd concentrations and the hazard quotient (HQ) for rice ingestion indicated that rice contamination had the most critical adverse effect on local residents. Due to the high levels of environmental Cd contamination, residents of the smelting area had a much higher Cd exposure than residents of the mining area. The results suggested that nonferrous mining and smelting should not coexist with agricultural activities. Effective contamination mitigation strategies and environmental remediation should be formulated and implemented to improve the health of local residents. Unlabelled Image • Most of the soil and rice Cd concentrations exceeded the national tolerance limits of China. • Dietary intakes of rice and vegetables were the major pathways of Cd exposure. • Non-carcinogenic and carcinogenic risks showed Cd exposure was highest to children. • Hazard quotient of rice consumption correlated with the hair Cd concentrations. • Residents in smelting areas suffered higher Cd exposure than those in mining area. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of nano zero-valent iron (NZVI, 50 nm) on anaerobic digestion of high solids sludge (10 ± 0.5%). Compared to the blank group without NZVI, the group with NZVI at all levels (10, 20 and 30 mM) played a driving role in methane production. The maximal methane production was increased by 37.5% in the group of 30 mM NZVI. The dynamic changes of hydrogen content and VFAs showed that rapid hydrogen evolutional corrosion of NZVI made lower hydrogen partial pressure in the later stage, which was more conducive to conversion of propionic acid. The microscopic analysis indicated that NZVI could flocculate and adsorb on the extracellular polymeric substances (EPS) around the anaerobic microorganisms, protecting most active microbial cell membrane from contact damage. On the other hand, some decaying microbial cells membrane could be destroyed by NZVI and intracellular substances would be released due to the reduction of EPS. Unlabelled Image • NZVI significantly enhanced the anaerobic digestion performance of high solids sludge. • The effect of hydrogen evolutional corrosion rate of NZVI and ZVI to conversion of propionic acid was investigated. • The effect of EPS after NZVI exposure in the high solids sludge was elucidated. • Variation of microbial community and metabolic pathways after NZVI addition were explored. [ABSTRACT FROM AUTHOR]

Abstract Regular impoundment of the Three Gorges Reservoir (TGR) with intensified human activities in the watershed imparts a significant effect on the environmental changes in the riparian zone. In this study, six heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) in the riparian sediments of the entire TGR mainstream were investigated in 2014 and 2016 to identify their contamination and risk characteristics and decipher the main factors for the variation of the metal contamination. The results showed that the concentrations of the heavy metals in the sediments did not vary significantly between 2014 and 2016, and their contamination degrees decreased in the order of Cd> > Cu ≈ Zn > Pb > Cr ≈ Ni in 2014 and Cd> > Zn > Cu ≈ Pb > Cr ≈ Ni in 2016. The potential eco-risk of Cd was extremely high in the two years, while the eco-risk of other metals was very low. The sediments showed a moderate to high contamination level, a high potential eco-risk but a low toxic risk to aquatic biota in the two years. Spatially, the contamination and risk levels of heavy metals were relatively higher in the downstream TGR region in 2014 except for the sites close to the urban areas but in the upper-middle TGR region in 2016. Increasing anthropogenic influence contributed to the high contamination and risk levels of Cd, Cu, Pb and Zn in the upper-middle region in 2016. The results indicated that the Cd contamination in the riparian sediments of the TGR was still a vital environmental issue, and the decreased sediment inputs from the upstream major tributaries, the periodic and anti-seasonal flow regulation, local geomorphological characteristics and anthropogenic activities determined the contamination distribution of heavy metals in the riparian sediments. Graphical abstract Unlabelled Image Highlights • Spatial variation of metal contamination in the riparian sediments could occur after the TGR flow regulation. • Higher contamination and eco-risk of metals existed in the downstream TGR in 2014 but in the upper-middle regions in 2016. • Cd was the concerned metal with high contamination and potential eco-risk in both years. • Human activities increasingly contributed to metal contamination in the upper-middle TGR region. • Decreasing sediment inputs, flow regulation, geomorphological and anthropogenic factors determined the metal redistribution. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO 2 ), methane (CH 4 ) and nitrous oxide (N 2 O) concentration, saturation and fluxes in rivers (Beitang drainage river, Dagu drainage rive, Duliujianhe river, Yongdingxinhe river and Nanyunhe river) of Tianjin city (Haihe watershed) were investigated during July and October in 2014, and January and April in 2015 by static headspace gas chromatography method and the two-layer model of diffusive gas exchange. The influence of environmental variables on greenhouse gases (GHGs) concentration under the disturbance of anthropogenic activities was discussed by Spearman correlative analysis and multiple stepwise regression analysis. The results showed that the concentration and fluxes of CO 2 , CH 4 and N 2 O were seasonally variable with > winter > fall > summer, spring > summer > winter > fall and summer > spring > winter > fall for concentrations and spring > summer > fall > winter, spring > summer > winter > fall and summer > spring > fall > winter for fluxes respectively. The GHGs concentration and saturation were higher in comprehensively polluted river sites and lower in lightly polluted river sites. The three GHGs emission fluxes in two sewage draining rivers of Tianjin were clearly higher than those of other rivers (natural rivers) and the spatial variation of CH 4 was more obvious than the others. CO 2 and N 2 O air-water interface emission fluxes of the sewage draining rivers in four seasons were about 1.20–2.41 times and 1.13–3.12 times of those in the natural rivers. The CH 4 emission fluxes of the sewage draining rivers were 3.09 times in fall to 10.87 times in spring of those in the natural rivers in different season. The wind speed, water temperature and air temperature were related to GHGs concentrations. Nitrate and nitrite (NO 3 − + NO 2 − − N) and ammonia (NH 4 + − N) were positively correlated with CO 2 concentration and CH 4 concentration; and dissolved oxygen (DO) concentration was negatively correlated with CH 4 concentration and N 2 O concentration. The effect of human activities on carbon and nitrogen cycling in river is great. [ABSTRACT FROM AUTHOR]

Abstract The contamination of heavy metals in sediments of the Three Gorges Reservoir (TGR) is increasingly concerned as a major issue for water quality since the full impoundment. In this study, the sediment profiles in the riparian and submerged areas from Fuling to Zigui in the middle-low TGR mainstream were collected to investigate the stratified distribution of heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) and assess their contamination and potential eco-risk. The results showed that the concentrations of these metals in the riparian sediments did not present a marked spatial trend except the concentrations of Cd that increased towards the dam. However, the metal concentrations (except Cd) in the submerged sediments were generally higher near the dam. The concentrations of heavy metals in the riparian sediments did not show marked vertical variation, while in the submerged sediments they fluctuated dramatically with depth, indicating the metal accumulation processes in last few years. Sediment grain sizes as an indicator of hydrodynamic regimes dominated the vertical distribution of heavy metals over organic matters and Fe/Mn oxide/hydroxides. The sediments from both riparian and submerged areas of the TGR were contaminated by anthropogenic metals of Cd, Cu and Pb that were mainly from the ore mining, fossil fuel combustion, agricultural pollution and atmospheric deposition. Cadmium was a major metal pollutant in the sediments with a high contamination and potential eco-risk level. The results of this study indicate that the sorting of sediments with the anti-seasonal flow regulation determines the spatial and temporal distribution of heavy metal contamination in the sediments, and the impoundment stages of the TGR in history regulate the accumulation processes of the metals. Graphical abstract Unlabelled Image Highlights • Spatiotemporal variation of heavy metal contamination in TGR sediments was investigated. • Vertical variation of metal concentrations was related to impoundment stages of the TGR. • Sediment grain-sizes dominated metal distribution over OMs and Fe/Mn oxides. • Anti-seasonal flow regulation and human activities regulated metal accumulation processes. • Cd contamination and eco-risk need to be concerned. [ABSTRACT FROM AUTHOR]

In this study, a core-shell Fe@Co nanoparticles uniformly modified graphite felt (Fe@Co/GF) was fabricated as the cathode by one-pot self-assembly strategy for the degradation of vanillic acid (VA), syringic acid (SA), and 4-hydroxybenzoic acid (HBA) in the Bio-Electro-Fenton (BEF) system. The Fe@Co/GF cathode showed dual advantages with excellent electrochemical performance and catalytic reactivity not only due to the high electron transfer efficiency but also the synergistic redox cycles between Fe and Co species, both of which significantly enhanced the in situ generation of H 2 O 2 and hydroxyl radicals (OH) to 152.40 μmol/L and 138.48 μmol/L, respectively. In this case, the degradation rates of VA, SA, and HBA reached 100, 94.32, and 100%, respectively, within 22 h. Representatively, VA was degraded and ultimately mineralized via demethylation, decarboxylation and ring-opening reactions. This work provided a promising approach for eliminating typical recalcitrant organic pollutants generated by the pre-treatment of lignocellulose resources. Schematic diagram of phenolic compounds degradation by Bio-Electron-Fenton system with Fe@Co/GF cathode. Unlabelled Image • A core-shell Fe@Co nanoparticles evenly modified graphite felt was fabricated. • Fe@Co/GF cathode showed high electron transfer efficiency and rapid redox cycles. • The excellent activity of the cathode enhanced the removal of phenolic compounds. • The possible mineralization pathway of vanillic acid was proposed. [ABSTRACT FROM AUTHOR]

Missing hydroxyl radical (OH) reactivity from unknown/unmeasured trace species empirically accounts for 10%–30% of total OH reactivity and may cause significant uncertainty regarding estimation of photochemical ozone production. Thus, it is essential to unveil the missing OH reactivity for developing an effective ozone mitigation strategy. In this study, we conducted simultaneous observations of total OH reactivity and 54 reactive trace species in a suburban area as part of the Air QUAlity Study (AQUAS)–Tsukuba campaign for the summer of 2017 to gain in-depth insight into total OH reactivity in an area that experienced relatively high contributions of secondary pollutants. The campaign identified on average 35.3% of missing OH reactivity among total OH reactivity (12.9 s−1). In general, ozone-production potential estimation categorized ozone formation in this area as volatile organic compound (VOC)-limited conditions, and missing OH reactivity may increase ozone production potential 40% on average if considered. Our results suggest the importance of photochemical processes of both AVOCs and BVOCs for the production of missing OH reactivity and that we may underestimate the importance of reducing precursors in approach to suppressing ozone production if we ignore the contribution of their photochemical products. Unlabelled Image • Total OH reactivity measurements were conducted in a suburban area. • In general, missing OH reactivity accounted for 35% of the 12.9 s−1 total OH reactivity. • Ozone production was VOC limited and missing OH reactivity may double its potential. • Moderate correlations exist between secondary products and missing OH reactivity. • Secondary products from both AVOCs and BVOCs may explain missing OH reactivity. [ABSTRACT FROM AUTHOR]

This work studied the impacts of ship emissions at a high temporal resolution on the real-time concentrations of PM 2.5 , NO 2 , and SO 2 in urban harbors and coastal sea areas, taking the Yangtze River Delta (YRD) as an example. The WRF-Chem model with 3 nested grids and ship emissions derived from an automatic identification system (AIS) were combined to simulate the air quality. The AIS data showed significant temporal fluctuations in ship emissions, with hourly mean fluxes of approximately 1082.41 ± 444.41 and 593.55 ± 404.95 g/h/km2 near ports and in the channel waters of the YRD, respectively. The monthly mean contributions of shipping emissions reached 80.72% (2.15 ppbv) and 81.79% (8.79 ppbv) to ambient SO 2 and NO 2 in Ningbo Port, and 10.61% (6.96 μg/m3) to PM 2.5 in Shanghai Port, respectively, regions with dense ship traffic. The relative differences in the PM 2.5 , SO 2 , and NO 2 concentrations modeled using monthly and hourly ship emissions accounted for −10–15%, −10–30%, and − 5–30%, respectively. Compared with cruise- and land-based measurements, the simulations using hourly emissions were in much better agreement with the observations than those using monthly emissions and appropriately captured some air pollutant concentration peaks. Simulations during shipping-related periods with hourly ship emissions improved the normalized mean bias (NMBs) from −43.03%, 301.49%, and 223.02% to −27.28%, 90.45%, and 167.52%, respectively, for PM 2.5 , SO 2 , and NO 2 , highlighting the importance of using ship emissions with a fine temporal resolution. Our study showed that ignoring hourly fluctuations in ship emissions during air quality modeling leads to considerable uncertainties, especially in coastal urban areas and harbors with high ship activities. These results imply that data with a high temporal resolution, such as hourly ship emissions, are necessary to understand the realistic impacts of shipping traffic and to implement more precise control policies to improve coastal air quality. Unlabelled Image • Hourly ship emissions showed large variations, especially near ports. • Simulations were evaluated by on-line cruise- and coastal land-based measurements. • Realtime emissions are crucial to explore realistic impacts of shipping traffic. [ABSTRACT FROM AUTHOR]

Minimization of cadmium (Cd) accumulation in wheat is an effective method to prevent Cd-related health risks to humans. To understand the underlying mechanisms of restricting Cd transport, the role of nodes in Cd restriction was studied in eight Chinese wheat cultivars. The Cd accumulation differed significantly among the cultivars. The grain Cd concentrations were mainly dependent on the Cd concentrations in the roots and shoots. The Cd transport in the shoots controlled the wheat grain Cd accumulations. Nodes in the wheat stem have distinct functions in the transfer, distribution, and restriction of Cd. The node connected to the panicle showed the lowest translocation factors. The area of the vascular bundles, especially the diffuse vascular bundles, in the junctional node with the flag leaf was the key factor in restricting Cd transfer to the wheat grain. There was a significant relation between these areas and the grain Cd concentrations. The conclusion of this study is that screening or breeding cultivars with low Cd concentrations in the roots or with smaller areas of diffuse vascular bundles in the junctional nodes with the flag leaf is an effective strategy to decrease Cd concentration in wheat grains. Unlabelled Image • Wheat grain Cd concentrations were mainly dependent on the root and shoot Cd concentrations. • Nodes have distinct functions in restriction of Cd, especially for the node connected to panicle. • The area of the vascular bundles showed significant relationship with grain Cd concentrations. • Low Cd in roots or smaller DVB areas help screening or breeding low-Cd accumulated cultivars. [ABSTRACT FROM AUTHOR]

The Ministry of Environmental Protection released a Joint Action Plan for Control of Air Pollution (Hereafter, Joint Action Plan, JAP), to reduce PM 2.5 concentrations in the Beijing-Tianjin-Hebei region (BTH) during the winter of 2017. To investigate the effectiveness of the controls, we deployed an aerosol chemical speciation monitor and collected filter samples at Xianghe, a representative site for the BTH, to characterize the aerosol composition during the implementation of the JAP. Those results were compared with earlier data obtained from a literature survey and reanalysis of studies in the BTH. During several pollution episodes in the control period, the major aerosol types changed relative to the earlier studies from sulfate, oxygenated organic aerosol, and coal combustion organic aerosol to nitrate and biomass burning organic aerosol. The dominant secondary inorganic aerosol species during the JAP changed from sulfate to nitrate, and the main source for primary organic aerosol switched from coal combustion to biomass burning. These changes can be explained by the fact that the JAP controls targeted coal combustion and SO 2 but not biomass burning or NO x emissions. Our evaluation of the control measures provides a scientific basis for developing new policies in the future. Unlabelled Image • Aerosol characteristics changed due to the implementation of Joint Action Plan. • The dominant secondary inorganic aerosol species changed from sulfate to nitrate. • The dominant primary organic sources changed from coal burning to biomass burning. [ABSTRACT FROM AUTHOR]

• A red paddy soil was incubated with hematite and hydroxyapatite for 42 days under flooding. • Hematite decreased soil Cu and Cd availability in the presence of hydroxyapatite. • The addition of hematite decreased soil labile phosphorus in the presence of hydroxyapatite. • Hematite plus hydroxyapatite is effective for Cu and Cd immobilization in soil. Hydroxyapatite (HA) is often applied as chemical amendment in soils contaminated with trace metals such as copper (Cu) and cadmium (Cd). Large amounts of iron oxides in red soil may interacts with phosphate released from HA and influence trace metal immobilization of HA. Here we simulated a red paddy soil with 1–5% wt iron oxides by adding hematite and evaluated the Cu and Cd availability in soil amended with HA under flooded conditions. Changes in phosphorus and iron oxide fractions were also evaluated after a 42-day flooding incubation experiment. Results showed that the addition of HA-only and hematite-only decreased soil redox potential and increased pore water pH compared to the control. HA combined with hematite could effectively decrease phosphate, Cu and Cd in soil pore water compared to HA-only. Additionally, HA combined with hematite could also increase soil pH and decrease soil CaCl 2 -extractable Cu and Cd. In particular, HA combined with 5% hematite was most effective in reducing soil exchangeable fractions of Cu and Cd by 53.7% and 65.6% compared to the control, respectively. The addition of HA-only increased water-soluble phosphorus, NaHCO 3 -extractable inorganic phosphorus, NaOH-extractable inorganic phosphorus, and HCl-extractable phosphorus. Conversely, HA combined with hematite treatments decreased NaHCO 3 -extractable inorganic phosphorus by 11.3–43.0% compared to HA-only. Vivianite and metal–phosphate precipitates were not observed using the Visual MINTEQ model, X-ray diffraction, and chemical analysis. The addition of hematite with or without HA increased free and crystal iron oxide fractions, while it substantially enhanced amorphous iron oxides in the soil. Thus, this study indicates that soil with high hematite content could enhance Cu and Cd immobilization while decreasing phosphorus availability in the red paddy soil amended with HA under the flooded conditions. [ABSTRACT FROM AUTHOR]

Aim at the effects of the coastal characteristic on ozone pollution in the Yangtze River Delta (YRD), a campaign was launched at the Ningbo, China in the summer of 2020, which mainly covered the monitoring of the vertical profiles of ozone (O 3 ) concentration, three-dimensional wind field, temperature and humidity profiles and parameters of boundary layer dynamic-thermodynamic structure. At the coastal research station, a sea-land breeze (SLB) circulation accompanied by a concurrent coastal low-level jets (CLLJ) structure was observed and identified during 11-12 May 2020. The sea breeze first formed at 10:00 LT on 11 May, turned to land breeze at night, and returned to sea breeze again at 10:00 LT the next morning, prevailing at altitudes of 0-0.5 km and 0-0.3 km respectively. Land breeze at night carries O 3 from the inland to the sea forming high ozone levels over the sea, and the shift of the sea breeze during daytime further blew pollution back to the land. Additionally, the conversion of SLB contributed to the occurrence of CLLJ at the altitudes of ~0.3-0.7 km by 02:00 and 06:00 LT, of which the center of wind speed reached ~13 m s -1 . The CLLJ-induced turbulent activity decoupled the residual layer (RL) and stable boundary layer, leading to a reduction of RL-O 3 levels and an increase of ~50 μg m -3 in surface-O 3 concentration. The YRD's unique coastal characteristics make O 3 pollution causes in coastal areas more complicated., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

There is growing interest in how heavy metals in remote ecosystems are elevated and affect environmental health. However, no studies have investigated atmospheric lead (Pb) deposition influences on the Pb bioaccumulation in insects in forests. Here we measure Pb concentrations and pools in forest vegetation, litterfall, organic soil, mineral soil, as well as litterfall deposition fluxes in a region severely affected by atmospheric deposition. We also analyzed Pb in insects which feed in the polluted forest vegetation and litter. Assessment of high Pb loads causing potential ecological risk to insects was also studied. Total Pb pool in the vegetation was 0.12 g m -2 and annual litterfall deposition flux of Pb was 13.42 mg m -2 , which was much higher than those in the background areas. Pools of Pb from litter to mineral topsoil averaged 4.3 g m -2 , which accounted for 97.3% of total pools (biomass + soil) in the forest ecosystem. Pools of Pb in surface soils were correlated significantly with the pools of total organic matter and elevation. Atmospheric deposition was inferred the major source of Pb in the forest ecosystem, which can be supported by the highest Pb concentrations in the moss and overstory foliage. The maximum Pb concentration was showed in the dung beetle (12.1 mg kg -1 ) residing in the soils compared that in the longicorn and of cicada, which would potentially pose negatively influence to predators along food chains., (Copyright © 2018 Elsevier B.V. All rights reserved.)