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Micro- and nano-plastics (MNPs) pollution has become a pressing global environmental issue, with growing concerns regarding its impact on human health. However, evidence on the effects of MNPs on human health remains limited. This paper reviews the three routes of human exposure to MNPs, which include ingestion, inhalation, and dermal contact. It further discusses the potential routes of translocation of MNPs in human lungs, intestines, and skin, analyses the potential impact of MNPs on the homeostasis of human organ systems, and provides an outlook on future research priorities for MNPs in human health. There is growing evidence that MNPs are present in human tissues or fluids. Lab studies, including in vivo animal models and in vitro human-derived cell cultures, revealed that MNPs exposure could negatively affect human health. MNPs exposure could cause oxidative stress, cytotoxicity, disruption of internal barriers like the intestinal, the air–blood and the placental barrier, tissue damage, as well as immune homeostasis imbalance, endocrine disruption, and reproductive and developmental toxicity. Limitedly available epidemiological studies suggest that disorders like lung nodules, asthma, and blood thrombus might be caused or exacerbated by MNPs exposure. However, direct evidence for the effects of MNPs on human health is still scarce, and future research in this area is needed to provide quantitative support for assessing the risk of MNPs to human health.

Abstract Due to anthropogenic activities, heavy metal (HM) pollution in soils has increased, resulting in severe ecological problems and posing a constant threat to human health. Among various remediation methods, bacterial remediation is a relatively clean, efficient, and minimally negative approach. However, bacterial agents face multiple environmental stresses, making them challenging to achieve long-lasting and stable restoration effects. To address this issue, supportive organic substances such as biochar can be added to the soil with bacteria. According to bibliometric studies, integrating biochar and bacteria is extensively researched and widely used for HM-contaminated soil remediation. By integrating biochar and bacteria, heavy metals in the soil can be remediated, and soil conditions can be improved over time. Bacteria can also better promote plant growth or contribute effectively to phytoremediation processes when assisted by biochar. However, the remediation agents integrating biochar and bacteria are still some distance away from large-scale use because of their high cost and possible environmental problems. Therefore, further discussion on the interaction between biochar and bacteria and the integration approach, along with their remediation efficiency and environmental friendliness, is needed to achieve sustainable remediation of HM-contaminated soils by integrating biochar and bacteria. This paper discusses the potential mechanisms of biochar-bacteria-metal interactions, current advancements in biochar-bacteria combinations for HM-contaminated soil treatment, and their application in sustainable remediation, analyzes the interaction between biochar and bacteria and compares the remediation effect of different ways and feedstocks to integrate biochar and bacteria. Finally, future directions of biochar-bacteria combinations are presented, along with evidence and strategies for improving their commercialization and implementation. Graphical Abstract

Introduction: Environmental microparticle is becoming a global pollutant and the entire population is increasingly exposed to the microparticles from artificial materials. The accumulation of microparticles including microplastics and its subsequent effects need to be investigated timely to keep sustainable development of human society. Objectives: This study aimed to explore the accumulation of environmental particles in thrombus, the pathological structure in the blood circulation system. Methods: Patients receiving cardiovascular surgical operations were screened and twenty-six thrombi were collected, digested and filtered. Non-soluble microparticles were enriched on the filter membrane and then were analyzed and identified with Raman Spectrometer. The associations of particle status (presence or absence) or particle number in the thrombus and clinical indicators were examined. One strict quality control-particle detection system was designed to eliminate environmental contaminations. Results: Among twenty-six thrombi, sixteen contained eighty-seven identified particles ranging from 2.1 to 26.0 μm in size. The number of microparticles in each thrombus ranged from one to fifteen with the median reaching five. All the particles found in thrombi were irregularly block-shaped. Totally, twenty-one phthalocyanine particles, one Hostasol-Green particle, and one low-density polyethylene microplastic, which were from synthetic materials, were identified in thrombi. The rest microparticles included iron compounds and metallic oxides. After the adjustment for potential confounders, a significantly positive association between microparticle number and blood platelet levels was detected (P < 0.01). Conclusion: This study provides the first photograph and Raman spectrum evidence of microparticles in thrombi. A large number of non-soluble particles including synthetic material microparticles could accumulate in arteries, suggesting that the risk of microparticle exposure was under-estimated and the re-evaluation of its health effects is urgently needed. There will be a series of reports on assessing the health effects of microparticle exposure in humans in the future and this research provided clues for the subsequent research.

Sulfur-resistant Mo-based catalysts have become promising for the one-step synthesis of methanethiol (CH3SH) from CO/H2/H2S, but the low reactant conversion and poor product selectivity have constrained its development. Herein, we synthesized K-MoS2/Al2O3 and K-Mo2C/Al2O3 catalysts via the sulfurization and carbonization of K-Mo-based catalysts in the oxidized state, respectively. During the synthesis of CH3SH, both K-Mo2C/Al2O3 and K-MoS2/Al2O3 showed excellent catalytic performance, and the activity of the former is superior to that of the latter. The effect of different treatments on the catalytic performance of Mo-based catalysts was investigated by XRD, BET, Raman spectroscopy, H2-TPR, and reactants-TPD characterization. The results showed that the sulfide-treated sample showed stronger metal-support interactions and contributed to the formation of K2S, which exposed more active sites and stabilized the formation of C-S bonds. Carbonized samples enhanced the activation of H2, which promoted the hydrogenation of the intermediate species of carbonyl sulfide (COS) and thus improved the selectivity of CH3SH.

Blue carbon ecosystems (BCEs), located at the land-sea interface, provide critical ecological services including the buffering of anthropogenic pollutants. Understanding the interactions between trace element (TE) loads in BCEs and socioeconomic development is imperative to informing management plans to address pollution issues. However, the identification of anthropogenic TE pollution in BCEs remains uncertain due to the complex geochemical and depositional processes and asynchronous socioeconomic development along continental coastlines. Here, priority-controlled TE (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn) concentrations in the mangrove, saltmarsh and seagrass soils and plant tissues along the coastline of China were investigated while taking bare flat and upland soils as corresponding references. We demonstrate that blue carbon (BC) soils accumulated markedly higher concentrations of anthropogenic TEs than the reference soils, mainly due to the effective trapping of fine-grained particles and higher binding capacities. We identify the time course of TE changes over the last 100 years which shows increasing anthropogenic TE accumulation resulting from military activities (1930–1950) and the growth of industrial and agricultural activities (1950–1980), then reaching a maximum after national economic reform (1980–2000). Since the 2000s, decreases in TE discharges driven by socioeconomic reform and strengthened environmental regulations have led to a widespread reversal of anthropogenic TE concentrations in BC soils. Based on the current TE flux we estimate that BCEs can filter over 27.3–100 % of the TEs emitted in industrial wastewaters from Chinese coastal provinces annually. However, the uptake of these TEs by plants can be substantially reduced through various mechanisms offered by edaphic properties such as organic carbon, clay, and sulfur contents. Therefore, enhancing TE filtering while preventing TEs from entering food webs through the conservation and restoration of BCEs will greatly aid in achieving the sustainable development goal of the coastal zone under intensified anthropogenic activities.

Metal sites immobilized by hydroxyl groups gain great attention, however, the role of adsorbed water derived by hydroxyl groups on the silica is generally ignored. Herein, the authors propose a new understanding of adsorbed water on the immobilization of highly dispersed tetrahedral Co(II).

Endogenous hydrogen (H2) is produced through rhizobium-legume associations in terrestrial ecosystems worldwide through dinitrogen fixation. In turn, this gas may alter rhizosphere microbial community structure and modulate biogeochemical cycles. However, very little is understood about the role that this H2 leaking to the rhizosphere plays in shaping the persistent organic pollutants degrading microbes in contaminated soils. Here, we combined DNA-stable isotope probing (DNA-SIP) with metagenomics to explore how endogenous H2 from the symbiotic rhizobium-alfalfa association drives the microbial biodegradation of tetrachlorobiphenyl PCB 77 in a contaminated soil. The results showed that PCB77 biodegradation efficiency increased significantly in soils treated with endogenous H2. Based on metagenomes of 13C-enriched DNA fractions, endogenous H2 selected bacteria harboring PCB degradation genes. Functional gene annotation allowed the reconstruction of several complete pathways for PCB catabolism, with different taxa conducting successive metabolic steps of PCB metabolism. The enrichment through endogenous H2 of hydrogenotrophic Pseudomonas and Magnetospirillum encoding biphenyl oxidation genes drove PCB biodegradation. This study proves that endogenous H2 is a significant energy source for active PCB-degrading communities and suggests that elevated H2 can influence the microbial ecology and biogeochemistry of the legume rhizosphere.

Precipitation datasets derived from reanalysis products play a crucial role in weather forecasting and hydrological applications. This paper aims to evaluate the performance of two distinct reanalysis precipitation products, i.e., the first-generation Chinese global land-surface reanalysis precipitation product (CRA40) and the fifth-generation European reanalysis precipitation product (ERA5), over mainland China. The evaluation is based on continuous and categorical statistical indicators with daily-scale gridded-point rain gauge data obtained from Chinese surface meteorological stations. The findings of this study can be summarized as follows: (1) CRA40 demonstrates a clear superiority over ERA5 in terms of the 13-year daily mean precipitation and seasonal daily precipitation. CRA40 exhibits better correlation coefficients (0.97), relative biases (5.25%), root mean square errors (0.34 mm), and fractional standard errors (0.05). (2) Both reanalyzed precipitation products generally exhibit an overestimation of precipitation in mainland China. The degree of overestimation is particularly pronounced in dry climatic regions (e.g., QZ, XJ), while wet regions (e.g., CJ, HN) demonstrate relatively less overestimation. (3) ERA5 shows better performance in the detection of daily precipitation. Neither CRA40 nor ERA5 can capture heavy precipitation events well. These findings are expected to advance our understanding of the strengths and limitations of the reanalysis precipitation products, CRA40 and ERA5, over China.

The cooperative transition of sulfur-containing pollutants of H2S/CO/H2 to the high-value chemical methyl mercaptan (CH3SH) is catalyzed by Mo-based catalysts and has good application prospects. Herein, a series of Al2O3-supported molybdenum carbide catalysts with K doping (denoted herein as K-Mo2C/Al2O3) are fabricated by the impregnation method, with the carbonization process occurring under different atmospheres and different temperatures between 400 and 600 °C. The CH4-K-Mo2C/Al2O3 catalyst carbonized by CH4/H2 at 500 °C displays unprecedented performance in the synthesis of CH3SH from CO/H2S/H2, with 66.1% selectivity and a 0.2990 g·gcat−1·h−1 formation rate of CH3SH at 325 °C. H2 temperature-programmed reduction, temperature-programmed desorption, X-ray diffraction and Raman and BET analyses reveal that the CH4-K-Mo2C/Al2O3 catalyst contains more Mo coordinatively unsaturated surface sites that are responsible for promoting the adsorption of reactants and the desorption of intermediate products, thereby improving the selectivity towards and production of CH3SH. This study systematically investigates the effects of catalyst carbonization and passivation conditions on catalyst activity, conclusively demonstrating that Mo2C-based catalyst systems can be highly selective for producing CH3SH from CO/H2S/H2.

ABSTRACT Protein acetylation can quickly modify the physiology of bacteria to respond to changes in environmental or nutritional conditions, but little information on these modifications is available in rhizobia. In this study, we report the lysine acetylome of Azorhizobium caulinodans strain ORS571, a model rhizobium isolated from stem nodules of the tropical legume Sesbania rostrata that is capable of fixing nitrogen in the free-living state and during symbiosis. Antibody enrichment and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis were used to characterize the acetylome. There are 2,302 acetylation sites from 982 proteins, accounting for 20.8% of the total proteins. Analysis of the acetylated motifs showed the preferences for the amino acid residues around acetylated lysines. The response regulator CheY1, previously characterized to be involved in chemotaxis in strain ORS571, was identified as an acetylated protein, and a mutation of the acetylated site of CheY1 significantly impaired the strain’s motility. In addition, a Zn+-dependent deacetylase (AZC_0414) was characterized, and the construction of a deletion mutant strain showed that it played a role in chemotaxis. Our study provides the first global analysis of lysine acetylation in ORS571, suggesting that acetylation plays a role in various physiological processes. In addition, we demonstrate its involvement in the chemotaxis process. The acetylome of ORS571 provides insights to investigate the regulation mechanism of rhizobial physiology. IMPORTANCE Acetylation is an important modification that regulates protein function and has been found to regulate physiological processes in various bacteria. The physiology of rhizobium A. caulinodans ORS571 is regulated by multiple mechanisms both when free living and in symbiosis with the host; however, the regulatory role of acetylation is not yet known. Here, we took an acetylome-wide approach to identify acetylated proteins in A. caulinodans ORS571 and performed clustering analyses. Acetylation of chemotaxis proteins was preliminarily investigated, and the upstream acetylation-regulating enzyme involved in chemotaxis was characterized. These findings provide new insights to explore the physiological mechanisms of rhizobia.

Rapid industrial development and extensive use of chemicals have resulted in elevated concentrations of emerging contaminants worldwide, posing a substantial threat to the ecological environment and human health. Per- and polyfluoroalkyl substances (PFASs) have been recognized as emerging pollutants that are widely distributed and accumulated in the environment and they have drawn the attention of scholars for several decades. The variety, long-term use, and long-distance transmission of PFASs have resulted in the ubiquitous contamination of global ecosystems, especially in aquatic environments. Ever since perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) were added to the Stockholm Convention on Persistent Organic Pollutants (POPs), they have become the most typical, eye-catching, and frequently investigated PFASs. Owing to the high stability and bioaccumulation of PFASs, as well as the adverse impact on the endocrine, immune, and nervous systems, investigating their contamination levels, risk of transfer along the food chain, and ecotoxicity should be prioritized. In addition to the important evolutionary significance as primitive vertebrates and the main consumers of aquatic environment, fishes generally exist in various aquatic food chains from the bottom to the top and occupy a critical position in terms of aquatic ecology protection; while amphibians, as the key link from aquatic to terrestrial organisms, are highly sensitive to different environmental pollutants. This review is a comprehensive summary of the toxic effects and toxicity-related factors of PFASs on aquatic vertebrates, mainly Pisces and Amphilla organisms, the characteristics of different aquatic vertebrates in toxicity investigations, and the evaluation of the feasibility of PFASs substitute applications.

The Yellow River Delta is an important grain production base in China, and it is a typical Yellow River irrigated area. Chemical fertilizer overuse has seriously affected grain production safety, and understanding the fertilizer application situation is useful for scientific agronomy management. In this study, we collected the data of the N, P, K fertilizers for crop cultivation in Donging City from 2011 to 2020, and we collected 185 investigating questionnaires to gather information on the fertilizer application rate for small farmers. The results showed that the amount of total fertilizer used has decreased from the year 2015, but the macro element fertilizer rate for crop cultivation exceeded the recommended dosage. The application of compound fertilizer increased during the investigated 10 years, and its proportion in 2020 was 1.65 times higher than in 2011. For obtaining an ideal grain yield, the N and P2O5 had relative reduction rates of 67.8% and 69.6% for wheat planting. Furthermore, the relative reduction rates of N, P2O5, and K2O were 25.9%, 69.6%, and 59.7%, respectively, for maize cultivation when compared to the recommended dosage. During wheat growth, the potassium fertilizer was needed to increase the dosage, although the K element content in the soil was high. Furthermore, the medium and trace elements are all important nutrients for improving crop yield and quality which need to be studied. More scientific measurements should be conducted to match chemical fertilizer reduction to constructing healthy and sustainable agriculture in the Yellow River irrigated area.

Per- and polyfluoroalkyl substances (PFASs) are a class of compounds that persist in the environment globally. Besides being transported to the soil and sediments, which act as their sinks, PFASs can be transferred to several species of higher organisms directly or via bacteria, eliciting a wide range of adverse effects. Caenorhabditis elegans has been widely used in toxicological studies and life science research owing to its numerous advantages over traditional vertebrate models; notably, C. elegans has 65% conserved human-disease-associated genes and does not require ethical approvals for experimental use. This review covers a range of topics, from reported accumulation characteristics and lethal concentrations of PFAS in C. elegans to the mechanisms underlying the toxicity of PFAS at different levels, including reproductive, developmental, cellular, neurologic, oxidative, metabolic, immune, and endocrine toxicities. Additionally, the toxicity levels of some PFAS substitutes are summarized. Lastly, we discuss the toxicological mechanisms of these PFAS substitutes and the importance and promising potential of nematodes as in vivo models for life science research, epidemiological studies (obesity, aging, and Alzheimer’s disease research), and toxicological investigations of PFASs and other emerging pollutants compared with other soil animals or model organisms.

Environmental science is an interdisciplinary science developed in the process of understanding and solving ecological and environmental problems. In order to tackle these problems, environmental science research is expected to reveal the source, behavior, fate, exposure, and risks of pollutants in the environment and develop potential solutions to control pollution. It provides the scientific basis for decision-makers to establish environmental and economic policies, and promote concerted efforts for the sustainable development of society. Here, we articulate the development patterns, challenges, and future research needs of environmental science in China based on literature review and expert panel discussion. Environmental science research has evolved significantly in the past decade with an increasing diversity of environmental pollutants and health impacts, new technologies and methods, deepening fusion of multiple disciplines, and emerging solutions for pollution control. Its future development relies on the advances in our knowledge on the fate and transport of pollutants, regional environmental processes, ecotoxicological effects, environmental exposure and health effects, environmental analysis and monitoring, source control and reduction, environmental remediation, as well as environmental risk management. For each of these fields, we summarize the significant challenges and highlight the research demands for China. Based on the status quo of China's environmental science research and future needs, we provide recommendations to promote its future development, including encouraging innovation and interdisciplinary research, providing decision support for national needs, encouraging international collaboration, and improving collaboration mechanisms.

Pets are the most intimate companions of humans, as pets and people share most of their lives indoors. Based on the connections between pet animals, humans, and the environment, pet cats and dogs are often recommended as sentinels for the detection of environmental contaminants and for comorbidity tracking. However, their suitability as sentinels is yet to be established. Persistent organic pollutants and environmental hormones have replaced particulate matter (PM2.5) and volatile organic compounds (VOCs) in causing indoor air pollution. This review summarises the differences in the types and concentrations of indoor organic environmental pollutants detected in pet dogs and cats. This includes an analysis of the main exposure routes of different types of pollutants. To identify which of the two pet species are better sentinels, cats and dogs were compared based on their metabolic capacities of various indoor organic pollutants. In addition to PM2.5, a range of organic compounds including polychlorinated biphenyls, polybrominated diphenyl ethers (PBDEs), bromophenols, perfluoroalkyl substances, organochlorine pesticides, fungicides, polycyclic aromatic hydrocarbons, phthalic acid esters, organophosphate pesticides, organophosphorus flame retardants, and melamine have been detected in both dogs and cats. Pets often accumulate PBDEs from dust; however, traces of PBDEs are present in their diet. The indoor pollutant contamination levels in internal cats were generally higher than those in dogs. Cats accumulate organic pollutants associated with indoor environments, but they are sensitive to their toxicity because, unlike dogs, cats cannot metabolise most of the accumulated pollutants. Moreover, cats share similar clinical symptoms of thyroid diseases in humans. Based on the above observations of detection of indoor organic pollutants, it could be said that cats are better sentinels than dogs.

Summary: The one-step reaction approach from syngas with hydrogen sulfide (CO/H2/H2S) over potassium (K) promoted Molybdenum disulfide (MoS2) materials can provide alternatives for the synthesis of methanethiol (CH3SH). However, the direct confirmation and determination of the real active nature of K-induced 2H and 1T′-MoS2 for this reaction and the corresponding phase transformation behavior and origin of K-induced 2H-MoS2 from/to 1T′-MoS2 remains unclear. Herein, we proved at the atomic level the precise position of K over 1T′-MoS2 and 2H-MoS2 species using the technique of HAADF-STEM. A relationship between K-induced 1T′ and 2H-MoS2 phases and the catalytic property to synthesize CH3SH was established, and K-intercalated 1T′-MoS2 phase was confirmed to have excellent catalytic performances. Moreover, the behavior, origin, and influencing factors of phase transformation of 2H-MoS2 from/to 1T′-MoS2 in the existence of K were well proved.

Salt stress seriously affects plant growth and crop yield, and has become an important factor that threatens the soil quality worldwide. In recent years, the cultivation of salt-tolerant plants such as Sesbania rostrata has a positive effect on improving coastal saline-alkali land. Microbial inoculation and GABA addition have been shown to enhance the plant tolerance in response to the abiotic stresses, but studies in green manure crops and the revelation of related mechanisms are not clear. In this study, the effects of inoculation with Azorhizobium caulinodans ORS571 and exogenous addition of γ-Aminobutyric Acid (GABA; 200 mg·L−1) on the growth and development of S. rostrata under salt stress were investigated using potting experiments of vermiculite. The results showed that inoculation with ORS571 significantly increased the plant height, biomass, chlorophyll content, proline content (PRO), catalase (CAT) activity, and superoxide dismutase (SOD) activity of S. rostrata and reduced the malondialdehyde (MDA) level of leaves. The exogenous addition of GABA also increased the height, biomass, and CAT activity and reduced the MDA and PRO level of leaves. In addition, exogenous addition of GABA still had a certain improvement on the CAT activity and chlorophyll content of the ORS571-S. rostrata symbiotic system. In conclusion, ORS571 inoculation and GABA application have a positive effect on improving the salt stress tolerance in S. rostrata, which are closely associated with increasing chlorophyll synthesis and antioxidant enzyme activity and changing the amino acid content. Therefore, it can be used as a potential biological measure to improve the saline-alkali land.

Irrigation is the primary agricultural utilization of water resources worldwide, and it produces 36% of the food. The quality of irrigation water influences crop growth and food safety. The coastal river delta region supplies huge area lands for developing agriculture, and the irrigation in this area is composed of many resources for its special location. This study investigated the agricultural water with different resources and evaluated its quality in the Yellow River Delta. The water samples included irrigation water, underground water, and drainage water. The sampling points were designed in the typical areas of Kenli county and Guangrao county in Dongying city, which is the core area of the Yellow River Delta. Through testing the ions composition and the parameters of electrical conductivity (EC), pH, and so on, six evaluation methods were conducted to assess the water quality. The results suggested that the Yellow River water has good quality for irrigation or unconventional water utilization. The high concentration of Na+ and Cl− was the primary problem of the water resource. The rainfall was also another water resource supplement in this region. Therefore, developing saline water irrigation incorporated with salt-tolerant crop cultivation is a rational measure for improving coastal agriculture in the Yellow River Delta.

Half the population of China live in coastal zones where 70% of large cities are also located. Intensive human activities pose significant environmental and ecological hazards to these cities that are already vulnerable to natural hazards and climate change. The sustainable development of coastal cities is thus both a national and international issue. Rongcheng is a typical coastal city in east China. It is a national marine ranch demonstration area that is subjected to multi-stressors from human activities and climate change. The dominant economic sectors include aquaculture and fisheries, agriculture, shipping and tourism. A multitude of resulting pressures come mainly from intensified human activities, such as intensive aquaculture, overfishing, industrial pollutants, agricultural runoff, land reclamation and port expansion. In addition, Rongcheng is also facing exogenic pressures from extreme climate events such as intensified storms, storm surges, droughts and sea ice. A growing awareness of these problems brought together a trans-disciplinary group from local government, research institutions, local practitioners and coastal representatives to jointly explore and co-design adaptive coastal management options. In this transdisciplinary study, a social-ecological analysis based on a combination of the Systems Approach Framework and the Drivers-Pressures-States-Impacts-Responses framework was used to analyze and formulate an adaptive management plan for the sustainability of Rongcheng. More than 40 stakeholders including government, companies, civil society and institutions participated in the study through questionnaires and on-site meetings. A statistical analysis of the results identified urgent issues impeding the sustainable development of Rongcheng. The issues identified were poorly regulated aquaculture, loss of shoreline, and the decline of seagrass and cultural heritage. The study identified management options and measures, some of which were adopted by the local government in a co-designed management plan. The measures included upgrading of aquaculture industry, habitat conservation and restoration, and the development of cultural tourism. Another outcome was the increased knowledge exchange between stakeholders to inform management, policy, and decision making, as well as raised awareness of vulnerability to natural hazards and climate change. The success of this case study provides a reference for the adaptive management of other coastal cities and their sustainable development in a changing climate.

The Yellow Sea (YS) is an epicontinental sea framed by the densely populated mainland of China and the Korean peninsula. Human activities over the last decades resulted in heavily increasing discharge of reactive nitrogen into the YS, which created numerous ecological problems. To elucidate the role of central YS in the cycling of reactive nitrogen, specifically the Yellow Sea Cold Water Mass (YSCWM), we determined nutrient concentrations, dual stable isotopes of nitrate (δ15N-NO3- and δ18O-NO3-), and stable isotopes of particulate and sedimentary nitrogen in spring and summer, i.e., in biologically inactive and active periods. The nitrate concentration in spring was higher than that in summer in the northern part of the YSCWM, Nitrate increased in the southern part accompanied by a decrease in δ15N-NO3- and δ18O-NO3-, which are indicative of nitrification that was a significant source of recycled nitrate in the south part of YSCWM. To quantify this regenerated nitrate, we use a mixing model with end members of preformed nitrate in spring and regenerated nitrate in summer, both with their distinct dual isotope values. The results suggest that only 35% nitrate was a residual of nitrate preformed in spring and 65% in summer in the southern branch of YSCWM was regenerated. The northern part of YSCWM has low concentrations of dissolved inorganic nitrogen, mainly because of denitrification in sediments. In contrast, the southern pool of YSCWM is a growing reservoir of regenerated terrestrial reactive nitrogen, the addition of which compensates the removal by co-occurring sediment denitrification. In consequence, the southern branch of YSCWM is facing a higher ecological risk than the northern branch, when excess reactive nitrogen discharge from Changjiang River continues at present levels or even increases.

Coastal saltmarshes are key ecosystems with important ecological functions. Yet, they have experienced a widespread decline. Due to their importance, the conservation and restoration of saltmarshes are globally shared objectives, including China. Despite multiple local studies, nationwide information about saltmarshes in China is scarce. Thus, we used remote sensing to delineate the spatial distribution and areal extent of saltmarshes along coastal China and resolve their species composition. By interpreting 10 m spatial resolution Sentinel-2 images on Google Earth Engine, assisted with field survey and literature search, a total of 118 010 ha of saltmarshes were delineated in coastal China in 2019. Seven typical saltmarsh species were identified, with Phragmites australis, Spartina alterniflora, and Scirpus mariquater as dominant species, accounting for 95.5% of total saltmarsh extent, while Suaeda salsa, Tamarix chinensis, Cyperus malaccensis, and Sesuvium portulacastrum were present in limited abundance. The P. australis and exotic species S. alterniflora grow along almost all coastal provinces, but P. australis dominates in the north while S. alterniflora dominates in the middle part of coastal China. Suaeda salsa occurs mainly in the north and has suffered large losses. Tamarix chinensis is abundant in Shandong province, S. mariquater in the Yangtze River delta, C. malaccensis in Guangdong and Guangxi provinces, and S. portulacastrum in Taiwan. The exotic species S. alterniflora expanded extensively along the coast and its expansion rate continues to increase. The results provided conform a much-needed baseline for future monitoring efforts and the assessment of progress in the conservation and restoration projects toward recovering saltmarshes in China.

As a representative sulfur-containing volatile organic compounds (S-VOCs), CH3SH has attracted widespread attention due to its adverse environmental and health risks. The performance of Mn-based catalysts and the effect of their crystal structure on the CH3SH catalytic reaction have yet to be systematically investigated. In this paper, two different crystalline phases of tunneled MnO2 (α-MnO2 and β-MnO2) with the similar nanorod morphology were used to remove CH3SH, and their physicochemical properties were comprehensively studied using high-resolution transmission electron microscope (HRTEM) and electron paramagnetic resonance (EPR), H2-TPR, O2-TPD, Raman, and X-ray photoelectron spectroscopy (XPS) analysis. For the first time, we report that the specific reaction rate for α-MnO2 (0.029 mol g−1 h−1) was approximately 4.1 times higher than that of β-MnO2 (0.007 mol g−1 h−1). The as-synthesized α-MnO2 exhibited higher CH3SH catalytic activity towards CH3SH than that of β-MnO2, which can be ascribed to the additional oxygen vacancies, stronger surface oxygen migration ability, and better redox properties from α-MnO2. The oxygen vacancies on the catalyst surface provided the main active sites for the chemisorption of CH3SH, and the subsequent electron transfer led to the decomposition of CH3SH. The lattice oxygen on catalysts could be released during the reaction and thus participated in the further oxidation of sulfur-containing species. CH3SSCH3, S0, SO32−, and SO42− were identified as the main products of CH3SH conversion. This work offers a new understanding of the interface interaction mechanism between Mn-based catalysts and S-VOCs.

This study mapped the areal extent, identified the species composition, and analyzed the changes of salt marshes in the intertidal zone of China during the period 1985–2019. With the aid of the cloud platform of the Google Earth Engine, we selected Landsat 5/8 and Sentinel-2 images and used the support vector machine classification method to extract salt marsh information for the years of 1985, 1990, 1995, 2000, 2005, 2010, 2015, and 2019. Seven major species of salt marshes: Phragmites australis, Suaeda spp., Spartina alterniflora, Scirpus mariqueter, Tamarix chinensis, Cyperus malaccensis, and Sesuvium portulacastrum were identified. Our results showed that salt marshes are mainly distributed in Liaoning, Shandong, Jiangsu, Shanghai, and Zhejiang, with varying patterns of shrinking, expansion, or wavering in different places. The distribution of salt marshes has declined considerably from 151,324 ha in 1985 to 115,397 ha in 2019, a drop of 23.7%. During the same period, the area of native species has dropped 95.4% from 77,741 ha to 3,563 ha for Suaeda spp. and 45.1% from 60,511 ha to 33,193 ha for P. australis; on the contrary, the area of exotic species, S. alterniflora, has exhibited a sharp rise from just 99 ha to 67,527 ha. For the past 35 years, the driving factors causing salt marsh changes are mainly land reclamation, variations in water and sand fluxes, and interspecific competition and succession of salt marsh vegetation. These results provide fundamental reference information and could form the scientific basis for formulating policies for the conservation and utilization of salt marsh resources in China.

Carbamazepine (CBZ) is a typical class of pharmaceuticals and personal care products (PPCPs), and is a serious threat to the environment and human health. Photocatalytic degradation is an efficient technology to remove CBZ. However, the present work focused mainly on the improvement of photocatalytic degradation performance. The information about the effects of inorganic ions on the photocatalytic degradation activity of environmental pollutants is still scarce. This study systematically investigated the effects of inorganic ions on the photocatalytic degradation of CBZ in view of the practical applications. The addition of inorganic anions showed a negative effect on photocatalytic degradation of CBZ with the order of inhibition effects of HCO3− > Cl− > NO3−. This was due to the quenching effects of hydroxyl radicals or holes, which decreased the photocatalytic degradation of CBZ. The presence of Al3+ could adsorb on the surface of a photocatalyst to shield the active site, resulting in the decreased CBZ degradation, while coexistence of Ca2+ significantly promoted the photocatalytic degradation of CBZ owing to the enhanced CBZ adsorption. Mg2+ showed concentration and time-dependent effects (suppression or promotion) on the photocatalytic degradation of CBZ.

Salt-affected soils is an important soil resource. Understanding fertilizer and salinity interaction are of great economic importance for improving crop yield and fertilizer use efficiency. A pot experiment was carried out to study the application of nitrogen (N) for ameliorating salt stress in wheat grown in the coastal saline soil of the Yellow River delta. Several controlling levels of salinity and nitrogen (0.7, 1.7, 2.7 g/kg, and 135, 270, and 405 kg/ha) were designed in a pot experiment in a stable water content state to investigate the N and salt interaction on soil properties and winter wheat growth characteristics. The results showed that the dry weight of winter wheat was promoted by salinity in the early growth stage (20 days), then it was gradually inhibited by nitrogen fertilizer. When winter wheat was grown by 54 days, the N and salinity had significant effects on the biomass of winter wheat. The nitrogen content of wheat shoot and root was mainly affected by N addition usage, and the largest value was obtained in 270 kg/ha N dosage treatments. The higher the salt content existed in the soil, the lower the growth rate shown in wheat cultivation. Under saline conditions, the N fertilizer application amount should be controlled to no more than 270 kg/ha, so that it could greatly promote wheat growth. Reasonable fertilizer usage could significantly contribute to crop yield and food quality of the saline agriculture in the Yellow River delta.

The summer maize-winter barley (or wheat) rotation system is a conventional farming method in coastal areas of east China. However, researchers have paid little attention to the increasing soil degradation after successive crop rotation in coastal saline agriculture. In the current study, a two-year field experiment was conducted to investigate the changes in soil physio-chemical properties and crop grain yields under the maize-barley rotation system. Wheat straw derived biochar (BC) was applied to topsoil (0~20 cm) at four different rates (0, 7.5, 15 and 30 Mg ha−1) before summer maize cultivation, and no biochar was added in the cultivation of the winter barley. Bulk density (BD), water holding capacity (WHC), water stable aggregate (WSA), soil electrical conductivity (EC), pH (1:5 water w/v) and soil organic carbon (SOC), at the harvesting time of maize and barley, were analyzed. The application of biochar increased WHC and macro-aggregate (>2 mm) content after barley harvest. Soil EC was mainly affected by the rain during maize cultivation and increased only slightly under BC treatments. However, no difference in EC was found among all treatments after barley harvest. The application of BC at 30 Mg ha−1 increased the maize yield by 66% but produced no difference in the barley yield. We concluded that biochar could be an effective option to mitigate soil degradation and improve crop productivity in coastal saline agriculture.

A field experiment was conducted to investigate the effects of biochar (BC), fulvic acid (FA) and Bacillus subtilis (BS) on soil properties and crop growth in the coastal salt-affected soil. Four levels of BC (0, 7.5, 15, 30 t ha−1), two levels of FA (0, 1.5 t ha−1) and BS suspension (0, 108 CFU mL−1) were designed during the maize cultivation. The results showed that 30 t ha−1 BC treatment was the most beneficial for improving the soil qualities. The grain yields in treatments containing FA and BS were lower than that in the BC treatments, and they were lower than that in the CK treatment. The treatment of 15 t ha−1 BC + BS obtained the highest grain yield, which was 1.75 times more than CK. An antagonism effect of the combination of FA and BS induced a grain yield decrease, and a higher content application of BC alleviated the negative effects.

Root colonization and plant probiotic function are important traits of plant growth-promoting rhizobacteria (PGPR). Bacillus velezensis SC60, a plant endophytic strain screened from Sesbania cannabina, has a strong colonization ability on various plant roots, which indicates that SC60 has a preferable adaptability to plants. However, the probiotic function of the strain SC60 is not well-understood. Promoting plant growth and suppressing soil-borne pathogens are key to the plant probiotic functions. In this study, the genetic mechanism of plant growth-promoting and antibacterial activity of the strain SC60 was analyzed by biological and bioinformatics methods. The complete genome size of strain SC60 was 3,962,671 bp, with 4079 predicted genes and an average GC content of 46.46%. SC60 was designated as Bacillus velezensis according to the comparative analysis, including average nucleotide polymorphism (ANI), digital DNA–DNA hybridization (dDDH), and phylogenetic analysis. Genomic secondary metabolite analyses indicated two clusters encoding potential new antimicrobials. The antagonism experiments revealed that strain SC60 had the ability to inhibit the growth of a variety of plant pathogens and its closely related strains of Bacillus spp., which was crucial to the rhizospheric competitiveness and growth-promoting effect of the strain. The present results further suggest that B. velezensis SC60 could be used as a PGPR strain to develop new biocontrol agents or microbial fertilizers.

CeO2 nanosphere-supported nickel catalysts were prepared by the wetness impregnation method and employed for hydrogen production from glycerol steam reforming. The dried catalyst precursors were either reduced by H2 after thermal calcination or reduced by H2 directly without calcination. The catalysts that were reduced by H2 without calcination achieved a 95% glycerol conversion at a reaction temperature of only 475 °C, and the catalytic stability was up to 35 h. However, the reaction temperature required of catalysts reduced by H2 with calcination was 500 °C, and the catalysts was rapidly inactivated after 25 h of reaction. A series of physicochemical characterization revealed that direct H2 reduction without calcination enhanced the concentration of oxygen vacancies. Thus, the nickel dispersion was improved, the nickel nanoparticle size was reduced, and the reduction of nickel was increased. Moreover, the high concentration of oxygen vacancy not only contributed to the increase of H2 yield, but also effectively reduced the amount of carbon deposition. The increased active nickel surface area and oxygen vacancies synergistically resulted in the superior catalytic performance for the catalyst that was directly reduced by H2 without calcination. The simple, direct hydrogen reduction method remarkably boosts catalytic performance. This strategy can be extended to other supports with redox properties and applied to heterogeneous catalytic reactions involving resistance to sintering and carbon deposition.

Coastal wetlands, such as saltmarshes and mangroves that fringe transitional waters, deliver important ecosystem services that support human development. Coastal wetlands are complex social-ecological systems that occur at all latitudes, from polar regions to the tropics. This overview covers wetlands in five continents. The wetlands are of varying size, catchment size, human population and stages of economic development. Economic sectors and activities in and around the coastal wetlands and their catchments exert multiple, direct pressures. These pressures affect the state of the wetland environment, ecology and valuable ecosystem services. All the coastal wetlands were found to be affected in some ways, irrespective of the conservation status. The main economic sectors were agriculture, animal rearing including aquaculture, fisheries, tourism, urbanization, shipping, industrial development and mining. Specific human activities include land reclamation, damming, draining and water extraction, construction of ponds for aquaculture and salt extraction, construction of ports and marinas, dredging, discharge of effluents from urban and industrial areas and logging, in the case of mangroves, subsistence hunting and oil and gas extraction. The main pressures were loss of wetland habitat, changes in connectivity affecting hydrology and sedimentology, as well as contamination and pollution. These pressures lead to changes in environmental state, such as erosion, subsidence and hypoxia that threaten the sustainability of the wetlands. There are also changes in the state of the ecology, such as loss of saltmarsh plants and seagrasses, and mangrove trees, in tropical wetlands. Changes in the structure and function of the wetland ecosystems affect ecosystem services that are often underestimated. The loss of ecosystem services impacts human welfare as well as the regulation of climate change by coastal wetlands. These cumulative impacts and multi-stressors are further aggravated by indirect pressures, such as sea-level rise.

The application of biochar in the remediation of heavy metal contaminated soil has received increasing global attention during the past decade. Although there has been some review work on the mechanism of heavy metals stabilization by biochar, the effects and mechanisms of interaction between biochar and functional microbes such as heavy metal tolerant, adsorption and transformation microbial strains remains unclear. In this paper, maize biochar and a heavy metal-tolerant strain Pseudomonas sp. NT-2 were selected to investigate the dynamic effects and potential mechanisms of biochar and bacteria loaded biochar on the stabilization of Cd and Cu mixed contaminated soil by a 75-day pot experiment. The results showed that, compared to the single biochar amendment, the application of biochar inoculated with NT-2 strain at the rate of 5% significantly increased the soil pH at the initial stage of incubation, and followed by a slight decline to a neutral-alkaline range during the reaction. The addition of NT-2 loaded biochar could also significantly increase the proportion of residual fraction of Cd and Cu, thus reduce the proportion of exchangeable and carbonate bound species in the soil, which lead to the decreasing of plant and human bioavailability of the metal in the soil indicated by DTPA and simulated human gastric solution extraction (UBM), respectively. Finally, the application of bacterial loaded biochar also markedly enhanced soil urease and catalase activities during the later stage of the incubation, and improved soil microbial community at the end of incubation, which indicates a recovery of soil function after the metal stabilization. The research results may provide some new insights into the development of functional materials and technologies for the green and sustainable remediation of heavy metal contaminated soil by the combination of biochar and functional microorganisms. Keywords: Biochar, Heavy metal, Microbe loaded biochar, Bioavailability, Stabilization, Soil enzyme activity

Microplastics (MPs, plastics 100 nm–5 mm in diameter) are estimated to accumulate in agricultural soils in quantities that exceed the total MP burden in ocean waters. Despite a wealth of information relating to the accumulation of MPs in aquatic species, there is little information on the uptake of MPs by terrestrial plants. Information about location of MPs in plant tissues is critical to understand the modes of their interaction with plants. Polystyrene (PS) is one of the most commonly used plastic polymers worldwide and it is often found in MPs sampled in the environment. The performance of traditional detection methods (i.e., transmission electron microscopy, TEM and scanning electron microscopy, SEM) for nanoparticles is limited due to the extensive sample preparation and the limited field of view. Here we report an approach for the imaging of different sizes of PS plastic beads (ranging from submicrometer to micrometer-sized) within plant tissues by using confocal laser scanning microscope (CLSM). Fluorescent dye Nile blue or 4-chloro-7-nitro-1,2,3-benzoxadiazole were encapsulated into the PS microbeads through swelling method and they were used to detect the localization of PS beads in the root and the green tissue respectively. • This is a simple and rapid approach for imaging of MPs in plant. • The fluorescent dyes can produce bright and stable emission signals that are distinguishable from the autofluorescence background of plant tissues. • The dyes leakage in the aqueous phase can be assumed to be negligible.

Abstract CoFe/C core–shell structured nanocomposites (CoFe@C) have been fabricated through the thermal decomposition of acetylene with CoFe2O4 as precursor. The as-prepared CoFe@C was characterized by X-ray powder diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy, transmission electron microscopy, and thermogravimetric analysis. The results demonstrate that the carbon shell in CoFe@C has a poor crystallization with a thickness about 5–30 nm and a content approximately 48.5 wt.%. Due to a good combination between intrinsic magnetic properties and high-electrical conductivity, the CoFe@C exhibits not only excellent absorption intensity but also wide frequency bandwidth. The minimum RL value of CoFe@C can reach − 44 dB at a thickness of 4.0 mm, and RL values below − 10 dB is up to 4.3 GHz at a thickness of 2.5 mm. The present CoFe@C may be a potential candidate for microwave absorption application.

Steam reforming of glycerol to produce hydrogen is considered to be the very promising strategy to generate clean and renewable energy. The incipient-wetness impregnation method was used to load Ni on the reducible carrier TiO2 (P25). In the process of catalyst preparation, the interaction and electronic effect between metal Ni and support TiO2 were adjusted by changing the calcination temperature, and then the activity and hydrogen production of glycerol steam reforming reaction (GSR) was explored. A series of modern characterizations including XRD, UV-vis DRS, BET, XPS, NH3-TPD, H2-TPR, TG, and Raman have been applied to systematically characterize the catalysts. The characterization results showed that the calcination temperature can contribute to varying degrees of influences on the acidity and basicity of the Ni/TiO2 catalyst, the specific surface area, together with the interaction force between Ni and the support. When the Ni/TiO2 catalyst was calcined at 600 °C, the Ni species can be produced in the form of granular NiTiO3 spinel. Consequently, due to the moderate metal–support interaction and electronic activity formed between the Ni species and the reducible support TiO2 in the NiO/Ti-600C catalyst, the granular NiTiO3 spinel can be reduced to a smaller Ni0 at a lower temperature, and thus to exhibit the best catalytic performance.

Abstract Mesoporous silica materials (MSMs) of the MCM-41 type were rapidly synthesized by microwave heating using silica fume as silica source and evaluated as adsorbents for the removal of Cu2+, Pb2+, and Cd2+ from aqueous solutions. The effects of microwave heating times on the pore structure of the resulting MSMs were investigated as well as the effects of different acids which were employed to adjust the solution pH during the synthesis. The obtained MCM-41 samples were characterized by nitrogen adsorption–desorption analyses, X-ray powder diffraction, and transmission electron microscopy. The results indicated that microwave heating method can significantly reduce the synthesis time of MCM-41 to 40 min. The MCM-41 prepared using citric acid (c-MCM-41(40)) possessed more ordered hexagonal mesostructure, higher pore volume, and pore diameter. We also explored the ability of c-MCM-41(40) for removing heavy metal ions (Cu2+, Pb2+, and Cd2+) from aqueous solution and evaluated the influence of pH on its adsorption capacity. In addition, the adsorption isotherms were fitted by Langmuir and Freundlich models, and the adsorption kinetics were assessed using pseudo-first-order and pseudo-second-order models. The intraparticle diffusion model was studied to understand the adsorption process and mechanism. The results confirmed that the as-synthesized adsorbent could efficiently remove the heavy metal ions from aqueous solution at pH range of 5–7. The adsorption isotherms obeyed the Langmuir model, and the maximum adsorption capacities of the adsorbent for Cu2+, Pb2+, and Cd2+ were 36.3, 58.5, and 32.3 mg/g, respectively. The kinetic data were well fitted to the pseudo-second-order model, and the results of intraparticle diffusion model showed complex chemical reaction might be involved during adsorption process.

Polysilazane (PSN2) was used as chemical foaming agent to prepare epoxy foam for the first time. Using the new foaming agent, epoxy foams with high strength and low density were successfully prepared. The density of epoxy foam can be tuned from 0.321 to 0.151 g cm−3 by changing the content of PSN2 from 2.50 to 7.50 wt%, with the compressive strength varied from 7.39 to 1.25 MPa. The morphology, porosity, mechanical property, thermal conductivity and adhesive property of foams with different polysilazane content were investigated. Besides, the effect of polyamine curing agent and surfactant on foams was also investigated to optimize the as-prepared epoxy foam.

In this work, a series of natural mordenite-supported platinum (Pt) catalysts were prepared by a facile two-step method, namely, treatment of natural mordenite and then the loading of Pt nanoparticles. The acid-alkali-treated natural mordenite-supported Pt samples (1% Pt/MORn-H-OH) exhibited the highly enhanced catalytic oxidation activity of formaldehyde (HCHO) at room temperature. XRD results showed that the crystalline phase of the mordenite did not change significantly in 1% Pt/MORn-H-OH catalyst. However, the acid-alkali treatment endowed the Pt particles excellent dispersion with the smallest diameter of 2.8 nm in a high loading content, which contributed to the optimal catalytic activity of 1% Pt/MORn-H-OH.

Large amount of phthalate esters (PAEs) used as plasticizers in polyvinyl chloride (PVC) products has caused ubiquitous contamination to the environment and potential ecology security risk all around the world, especially in places plastic films were indispensably utilized due to the widely proposing of facility agriculture in China. A case of PAEs contamination in four suburb areas of Nanjing was analyzed and discussed in this study. A new frame work has been put forward based on multi-criteria evaluation model and mathematical method of catastrophe theory, using farming work, laboratory determination and relevant environmental standards to measure the ecology security risk of PAEs in study areas. The factors were selected based on the availability of the data and the local conditions. The assessment model involves the contamination status of PAEs in soil and vegetables, the contamination effects of PAEs to human and soil organisms and the contamination source of PAEs from plastic films and other products in the four study facility agriculture areas. An evaluation system of the model was composed of thirteen mesosphere indicators and twenty-five underlying indicators including total PAEs concentration in soils, single PAE concentration in soils, total PAEs concentrations in roots, leafy, solanaceous and stem vegetables, PAE human risks, soil microbial counts, microorganism diversity indices, atmospheric deposition of PAEs, whether sewage wastewater irrigation, planting mode of the facility agriculture areas and climate condition of study areas. The modified evaluation system was used in the assessment of ecology security of the same place based on the data of 2012, and the results suggested that the ecology security indicators were reliable and were agree well with the practical situation of the study areas. The results could provide guidance for the application of health risk assessment of soil environment for the strong objectivity of catastrophe theory compared with other evaluation methods.

Di-(2-ethylhexyl) phthalate (DEHP) is a dominant phthalic acid ester (PAE) that has aroused public concern due to its resistance to degradation and its toxicity as an endocrine-disrupting compound. Effects of different concentrations of DEHP on Eisenia fetida in spiked natural soil have been studied in the body of the earthworm by means of soil cultivation tests 7, 14, 21 and 28 days after exposure. The results indicated that, in general, superoxide dismutase (SOD) activity, malondialdehyde (MDA) content, metallothionein (MT) content, the expression of heat shock protein 70 (HSP 70) and all the tested geno-toxicity parameters are promoted as time elapses and with increasing concentration of DEHP. However, peroxidase (POD) activity, neutral red retention time (NRRT) and mitochondrial membrane potential difference values were found to decrease even at a low concentration of DEHP of 1 mg kg-1 soil (p

Recognized as ubiquitous contaminants in soil, the environmental risk of phthalic acid esters (PAEs) is of great concern recently. Effects of di-n-butyl phthalate (DnBP), an extensively used PAE compound to Eisenia fetida have been investigated in spiked natural brown yellow soil (Alfisol) for soil contact test. The toxicity of DnBP to E. fetida on the activity of superoxide dismutase (SOD) activity, peroxidase (POD), reactive oxygen species (ROS) content, and the apoptosis of coelomocytes and DNA damage at the 7th, 14th, 21st and 28th day of the incubation have been paid close attention to. In general, SOD activity and ROS content were significantly induced, opposite to total protein content and POD activity, during the toxicity test of 28 days especially under concentrations higher than 2.5 mg kg-1. The reduction in neutral red retention (NRR) time along with the increase of dead coelomocytes as the increasing of DnBP concentrations, indicating severe damage to cell viability under varying pollutant stress during cultivation, which could also be proved by comet assay results for exerting evident DNA damage in coelomocytes. DnBP in spiked natural soil could indeed cause damage to tissues, coelomocytes and the nucleus of E. fetida. The key point of the apparent change in different indices presented around 2.5 mg DnBP kg-1 soil, which could be recommended as the threshold of DnBP soil contamination, so that further investigation on threshold values to other soil animals or microorganisms could be discussed.

Satellite-based precipitation estimates products, CMORPH and PERSIANN-CCS, were evaluated with a dense rain gauge network over Beijing and adjacent regions for an extremely heavy precipitation event on July 21 2012. CMORPH and PEERSIANN-CSS misplaced the region of greatest rainfall accumulation, and failed to capture the spatial pattern of precipitation, evidenced by a low spatial correlation coefficient (CC). CMORPH overestimated the daily accumulated rainfall by 22.84% while PERSIANN-CCS underestimated by 72.75%. In the rainfall center, both CMORPH and PERSIANN-CCS failed to capture the temporal variation of the rainfall, and underestimated rainfall amounts by 43.43% and 87.26%, respectively. Based on our results, caution should be exercised when using CMORPH and PERSIANN-CCS as input for monitoring and forecasting floods in Beijing urban areas, and the potential for landslides in the mountainous zones west and north of Beijing.

Amino-functionalized mesoporous silica MCM-41 materials have been prepared to develop efficient adsorbents of Cr(VI) in wastewater, using silica fume as silica source. Functionalization with amino groups has been carried out by using grafting method. The materials have been characterized by means of X-ray diffraction (XRD), nitrogen (N2) adsorption-desorption, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). Adsorption potential of the material for Cr(VI) removal from aqueous solution was investigated by varying experimental conditions such as pH, initial metal concentration, and contact time. The equilibrium data were analyzed using the Langmuir and Freundlich isotherm by linear regression analysis, and the results show that the adsorption equilibrium data obeyed the Langmuir model. In addition, the kinetics analysis revealed that the overall adsorption process was successfully fitted with the pseudo-second-order kinetic model.

Nitrous acid (HONO) and nitrogen oxides (NOx = NO + NO2) are important atmospheric pollutants and key intermediates in the global nitrogen cycle, but their sources and formation mechanisms are still poorly understood. Here, we investigated the effect of soluble iron (Fe3+) on the photochemical behaviour of a widely used neonicotinoid (NN) insecticide, nitenpyram (NPM), in the aqueous phase. The yields of HONO and NOx increased significantly when NPM solution was irradiated in the presence of iron ions (Fe3+). We propose that the enhanced HONO and NO2 emissions from the photodegradation of NPM in the presence of iron ions result from the redox cycle between Fe3+ and Fe2+ and the generated reactive oxygen species (ROS) by the electron transfer between the excited triplet state of NPM and the molecular oxygen O2). Using the laboratory-derived parametrization based on kinetic data and gridded downward solar radiation, we estimate that the photochemistry of NPM induced by Fe3+ releases 0.50 and 0.77 Tg N year-1 of NOx and HONO to the atmosphere, respectively. This study suggests a novel source of HONO and NOx during daytime and potentially helps to narrow the gap between the field observations and model outcomes of HONO in the atmosphere. The suggested photochemistry of NPM can be an important contribution to the global nitrogen cycle affecting the atmospheric oxidizing capacity as well as the climate change. [ABSTRACT FROM AUTHOR]

With mankind entering the smart age, Cd contamination risk control in food crop revolution has been put on the agenda. Based on the theoretical basis, technical methods and developing trends, this review look back and forward the age of Cd contamination risk control driven by 'genotype (G)+ envirotype (E)' dual-engines. Focusing on G, an inter-specific Cd contamination risk assessment meta-analysis was carried, in which a higher Cd contamination risk in rice and wheat than maize was observed. So different strategies are recommended to be taken considering inter-specific difference. To control the risk in crops with high accumulating characteristic, smart creation of low-Cd crops can be applied by two methods: 1) Excavating and pyramiding natural variations in natural population and 2) designing and implementing artificial variations which do not exist in natural population. Focusing on E, the influence of environmental factors to food crop Cd accumulation was discussed and the strategy using Envirotype-to-phenotype (E2P) models to predict and implement safety threshold were offered. In the foreseeable future, with the support of environmental science, biology, big data, artificial intelligence and other interdisciplinary and multi-technology, Cd contamination risk control will move toward intelligent, efficient and directional, ultimately realizing the revolutionary transformation from 'experience' to 'smart'. [ABSTRACT FROM AUTHOR]