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Microplastic pollution in agricultural soil threatens soil quality and human health which has attracted extensive attention worldwide. However, there is no uniform standard for microplastic extraction methods and the identification of microplastic component in different typical agricultural soils. In this study, an artificial simulation adding experiment was used in eight typical agricultural soil samples in China. The aim of the study was to use different methods for extraction, comparing the extraction rates of four microplastics and their influence on polymer identification using ATR- FTIR. The two separate methods were oil extraction (water + oil and saturated NaCl solution + oil), and density method (saturated NaCl solution). The four types of microplastics include polyethylene terephthalate (PET), polypropylene (PP), polystyrene (PS), and polyethylene (PE). We found that the oil extraction method effectively extracted four types of microplastics in agricultural soils, which varied from 83.33% to 100.00%. However, the extraction rate of PET under the oil extraction method and PP under the density method from Southern laterite area was lower than other soils. The presence of iron and aluminum ions influenced the extraction rates of microplastics in the Southwest laterite area. With the increase in microplastic density, the extraction rates of the density method decrease. The oil extraction methods with the cleaning of residual oil were recommended for the higher density microplastics. The density method was recommended for the lighter microplastics in agricultural soils. However, these two extraction methods were not ideal to extract the microplastics from the Southern laterite area and the appropriate extraction methods for laterite need to be further studied in the future. Our results can provide technical support for the extraction treatment and scientific microplastic pollution control of typical agricultural soils with different erosion areas. [ABSTRACT FROM AUTHOR]

Microplastics in marine environments are becoming a hot topic since they can be transferred through the marine food web and may finally be consumed by humans. Here, we investigate the distribution characteristics of microplastics in marine organisms at different trophic levels through their digestive tracts (entire organisms for zooplankton and zoobenthos). A total of 124 fish and 22 crustaceans from 10 fish and 3 crustacean species, as well as a few zooplankton and zoobenthos, were captured from the Zhoushan fishing ground, i.e., China's largest ocean fishing ground. The abundance of microplastics ranged from 0.74 ± 1.29 to 4.71 ± 2.19 items per sample in fish species and from 0.83 ± 1.07 to 1.00 ± 0.93 items per sample in crustacean species. Among the detected microplastics, fiber was the most dominant type (i.e., 67%), transparent microplastics were the most frequently detected (i.e., 49%), and the majority of the microplastics were identified as natural particles (cellulose). The abundance of microplastics was positively correlated with the trophic level (correlation coefficient = 0.717; p < 0.05). Our results show that microplastics are widespread in the marine organisms of the Zhoushan fishing ground, and they might accumulate in marine organisms at higher trophic levels of the marine food chain. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) pervade the environment and increasingly threaten both natural ecosystems and human health. In this study, we investigated MP particle concentrations in sediment samples collected from 54 sites along the banks of the Yangtze River and its major tributaries and on lakeshores. The main polymer types found in the samples were polypropylene (PP), polystyrene (PS) and polyethylene (PE). MP particle abundance in the various types of locations was 35–51,968 particles/kg dry weight (d.w.) on the banks of the main river, 52–1463 particles/kg (d.w.) on the banks of tributaries and 2574–23,685 particles/kg (d.w.) on lakeshores. Correlation between MP abundance and mean annual runoff of each upstream tributary was significant, which suggests that increased runoff brings more microplastic waste to streambank sediments. The most common shape of MP particles in all upstream samples was flake, and in downstream samples it was foam. Small microplastic particles (< 0.50 mm) were predominant at all sites in this study, and the minimum particle size in samples from the Yangtze river banks was 0.065 mm. Average abundance of MP particles on the shores of the source lake was 9069 particles/kg around the inlet but only 866 particles/kg around the outlet; the difference was due to interception associated with sedimentation and precipitation in the lake. Our study represents the large-scale study of MPs contamination in sediment along the Yangtze River and provides important data regarding the accumulation and distribution of MPs in shoreline sediments of the upper, middle and lower reaches of the Yangtze River, main tributaries and lakes in China. [ABSTRACT FROM AUTHOR]

In this study, we present a preliminary investigation of the characteristic changes in microplastic during the production process of sea salt in China. Five representative samples, including seawater, saturated brine, crude salt, coarse salt, and refined salt were successively collected from the production process of sea salt sourced from the Bohai Sea in China. The pretreatment method of microplastics was optimised and evaluated by the recovery rates of particle references. Microplastic characteristics in the five samples were investigated using consistent pretreatment, microscopic, and spectroscopic analyses. Results indicated that microplastics were present in every stage of sea salt production. During the "journey" of microplastics in salt production from seawater-to-seawater evaporation, to salt crystallisation, and external force processing, the abundance of microplastics with size ranging from 18 μm to 4936 μm increased substantially from 23 ± 8 to 413 ± 61 particles kg−1, while the proportion of larger microplastics (≥1000 μm) decreased from 33% to 9%. The results illustrate the effect of the production process on microplastic contamination of sea salt. [ABSTRACT FROM AUTHOR]

Microplastic pollution is ubiquitous in the marine environment and the consumption of shellfish containing microplastics may pose a risk to human health. This study investigated the occurrence and characteristics of microplastics in three commonly consumed shellfish in the coastal region of Jiangsu Province, China. The average abundance of microplastics in shellfish varied from 0.33 to 9.33 items/individual (0.06–0.92 items/g, wet weight of soft tissue). Microplastic abundance in Jiangsu was relatively low compared to studies from other regions of China and worldwide. Synthetic fibers (66.20%) were predominant and included rayon (34.84%) and polyester (23.23%), indicating that the majority of particles originated from the discharge of clothing fibers in domestic sewage. Transparent (66.20 %) particles were the most common, particle size was generally less than 500 μm (62.30%), and abundance decreased as the particle size increased. The average annual intake of microplastics by Jiangsu coastal residents via the consumption of common bivalves was estimated to be 1088.64 items/person/year. This study provides data to support ecological and health risk assessments for microplastics in the Jiangsu coastal region. [ABSTRACT FROM AUTHOR]

With the rapid development and democratization of the internet and smart phone industry, online food delivery services have become increasingly popular all over the globe, namely in China. One of the unfortunate drawbacks of these delivery services is that they mainly use single-use plastics as food packaging, therefore generating large amounts of disposable food containers to meet demand. Such plastic containers reach the end of their service life after a single meal, and are then discarded as plastic waste. The sheer amount of plastic food containers discarded in this manner exacerbates various environmental issues, including one that is invisible to the naked eye: microplastic pollution. This minireview summarizes the history of food delivery services in China, from orders made face-to-face to digital orders, as well as the consequences introduced by the tremendous amounts of plastic waste generated by the food delivery services. Microplastic pollution could be mitigated to a certain extent by improving the classification, handling and management of single-use plastic containers in China. Furthermore, additional studies focusing on microplastic pollution caused by food delivery services are needed, especially as the use of these services is on the rise worldwide. [ABSTRACT FROM AUTHOR]

The high-tech industry is the main force promoting the development of China's national economy. As its industrial economic strength grows, China's high-tech industry is increasingly using cross-border mergers and acquisitions (CBM&A) as an important way to "go out." To explore the rules governing the process and operation mechanism of reverse knowledge transfer (RKT) through the CBM&A of China's high-tech industry under government intervention, a tripartite evolutionary game model of the government, the parent company, and the subsidiary as the main subjects is constructed in this paper. The strategies adopted by the three subjects in the RKT game process are analysed, and the factors influencing RKT through CBM&A under government intervention are simulated and analysed using Python 3.7 software. The results show that, under government intervention, the parent company and subsidiary have different degrees of influence on each other. Subsidiaries are highly sensitive to the compensation rate of RKT. Positive intervention by the government tends to foster stable cooperation between the parent company and the subsidiary. However, over time, the government gradually relaxes its intervention in the RKT and innovation of multinational companies. [ABSTRACT FROM AUTHOR]

In previous studies, most scholars merely focused on the direct effect of inter-organizational learning on alliance performance and the impact of relationship capital on the learning between alliance organizations, while ignoring the fact that inter-organizational learning may also exert a significant positive effect on relationship capital and further influence alliance performance through the intermediary of relationship capital. This article constructs a theoretical model of the indirect impact mechanism of the learning between alliance organizations on alliance performance with relationship capital as the mediator. Based on the questionnaire data of 210 alliance enterprises in China, this article empirically researches into the relationship among inter-organizational learning, relationship capital (trust and relationship commitment) and alliance performance. The findings suggest that in the specific management situations in China, the learning between alliance organizations can affect alliance performance not only in a direct manner, but also in an indirect manner through the intermediary of relationship capital. By summing up the empirical results, the article puts forward some suggestions on management practices to further enrich the understanding of the value of learning between alliance organizations. [ABSTRACT FROM AUTHOR]

How microbes respond to substantial and increasing anthropogenic disturbance remains an open question in river systems. We tested the hypothesis that the source and distribution of anthropogenic organic matter (OM) were significant factors affecting the spatial variation of the microbial community composition of the Yangtze River sediments. Bulk geochemical proxies and lignin phenols suggested a general decrease of terrestrial C3 plants or soil OM input from the middle to the lower reaches. Fecal sterols inferred higher sewage contamination levels in the middle reaches. Polycyclic aromatic hydrocarbons (PAHs) distribution indicated a dominant biomass and coal combustion signal in the middle reaches, whereas a mixed source including petroleum combustion in the lower reaches. Phylogenetic analysis revealed a large portion of Methanobacteria and Verrucomicrobia enriched in the middle reaches, whereas OM-degrading bacteria, including Flavobacteria, Acidobacteria, and Alphaproteobacteria were dominant in the lower reaches. Quantitative PCR analyses and multivariate analysis further demonstrated that sources and distribution of OM had combined effects in shaping alpha and beta-diversity of sediment microbial communities. Sewage discharge and incomplete OM combustion, respectively, were associated with Methylococcaceae, Chloroflexi, and Bacteroidetes groups. This study provides a foundation for further understanding of the river sediment microbial composition, considering the continued increase of anthropogenic influences. [ABSTRACT FROM AUTHOR]

Microplastic pollution has been considered as a global environmental issue that potentially threatens human health. However, research about microplastic pollution in urban rivers is still insufficient. This study analyzed the abundance and distribution of microplastics in surface water of the Nanfei River in Hefei, China. Microplastic concentrations ranged from 0.8 to 27 items/L along the studied river. The small size (50-333 μm) (47.58-84.89%) and white (55.65-88.89%) were predominant among all samples, except that collected from the source reach. Pellet was a typical and abundant microplastic type and accounted for 60.30%. PE and PP were the major polymers, occupying 55.24% and 22.86%, respectively. The results showed that traditional environmental management practices including salvaging surface garbage regularly and setting wooden suspended crossbars at tributary confluences could significantly mitigate the pollution degree of microplastics. The polymer risk index was calculated to describe the potential risk of microplastics, and the pollution level was still at high risk under various management practices. This study provides a valuable finding for future research on microplastics in urban city rivers, which may improve the knowledge that how to control and prevent microplastic pollution., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

Atmospheric deposition is considered to be a major process that removes pollutants from the atmosphere and an important source of nutrients and contaminants for ecosystems. Trace elements (TEs), especially toxic metals deposited on plants and into soil or water, can cause substantial damage to the environment and human health due to their transfer and accumulation in food chains. Despite public concerns, quantitative knowledge of metal deposition from the atmosphere to ecosystems remains scarce. To advance our understanding of the spatiotemporal variations in the magnitudes, pathways, compositions and impacts of atmospherically deposited TEs, precipitation (rain and snow) and dry-deposited particles were collected simultaneously at 10 sites in Northern China from December 2007 to November 2010. The measurements showed that the wet and dry depositions of TEs in the target areas were orders of magnitude higher than previous observations within and outside China, generating great concern over the potential risks. The spatial distribution of the total (wet plus dry) deposition flux was consistent with that of the dry deposition, with a significant decrease from industrial and urban areas to suburban, agricultural and rural sites, while the wet deposition exhibited less spatial variation. In addition, the seasonal variation of wet deposition was also different from that of dry deposition, although they were both governed by the precipitation and emission patterns. For the majority of TEs that exist as coarse particles, dry deposition dominated the total flux at each site. This was not the case for potassium, nickel, arsenic, lead, zinc, cadmium, selenium, silver and thallium, for which the relative importance between wet and dry deposition fluxes varied by site. Whether wet deposition is the major atmospheric cleansing mechanism for the TEs depends on the size distribution of the particles. We found that atmospheric inputs of copper, lead, zinc, cadmium, arsenic and selenium were of the same magnitude as their increases in the topsoil of agricultural systems. At a background forest site in Northern China, the total deposition flux of lead observed in this study (14.1 mgm-2 yr-1) was twice that of the critical load calculated for temperate forest ecosystems in Europe. These findings provide baseline data needed for future targeting policies to protect various ecosystems from long-term heavy metal input via atmospheric deposition. [ABSTRACT FROM AUTHOR]

South Korean multinational enterprises (MNEs) have developed rapidly since the late 1950s. However, there is little research on, and hence little is known about, how South Korean MNEs manage human resources in overseas operations. To fill this gap, in the literature the current study investigates South Korean MNEs' international recruitment and selection policies and practices in their Chinese operations. It reveals that South Korean MNEs tend to adopt the polycentric approach or a mixed approach of being polycentric and ethnocentric to international staffing, with the number of expatriates dropping gradually over time. South Korean MNEs adopt ‘one-way selection’ in recruiting and selecting expatriates, and localise recruitment procedures and selection criteria for host-country nationals. South Korean MNEs have paid inadequate attention to: first, expatriates' career development; and second, personal and family issues emerging from expatriation and repatriation. [ABSTRACT FROM PUBLISHER]

The rapid expansion of urban impervious surface areas complicates urban-scale heavy metal circulation among various environmental compartments (air, soil, sediment, water, and road dust). Herein, a level III steady-state aquivalence model evaluated the fate of heavy metals in Nanjing, China. Iron was the most abundant heavy metal in all environmental compartments, while cadmium was the rarest. Most simulated concentrations agreed with measured values within three logarithmic residuals. In the simulated heavy metal cycle, industrial emission contributed almost the entire input, whereas sediment burial was the dominant output pathway. The transfer fluxes between bottom sediment and water were the highest. Thereinto, the contribution of sediment resuspension for Fe and Mn was significantly higher than that to the other metal elements, which could partly explain why Fe and Mn are the major blackening ingredients in malodorous black rivers. Road dust was also an important migration destination for heavy metals, accounting for 3–45%, although soil and sediment were the main repositories of heavy metals in the urban environment. The impact of road dust on surface water should not be neglected, with its contribution reaching 4–31%. The wash-off rate constant W for road dust–water process was proved to be consistent with that for film–water and was independent of the type of heavy metals. Sensitivity analysis highlighted the notable background value effect on Fe and Mn. [ABSTRACT FROM AUTHOR]