Arsenic(III) sequestration by terrestrial-derived soil protein: Roles of redox-active moieties and Fe(III).

Glomalin-related soil protein (GRSP) has demonstrated significant potential for water purification and remediation of heavy metals in soils; however, its redox reactivity for As(III) sequestration and the corresponding redox-active component are still poorly understood. This study investigated the photochemical properties of GRSP and its mechanism of oxidation/adsorption of As(III). The results showed that UV irradiation triggered electron transfer and the production of reactive oxygen species (ROS) in GRSP, thereby facilitating As(III) oxidation with promotion rates ranging from 43.

Comparative analysis of size-fractional eukaryotic microbes in subtropical riverine systems inferred from 18S rRNA gene V4 and V9 regions.

Eukaryotic microbes play key ecological roles in riverine ecosystems. Amplicon sequencing has greatly facilitated the identification and characterization of eukaryotic microbial communities. Currently, 18S rRNA gene V4 and V9 hypervariable regions are widely used for sequencing eukaryotic microbes.

Microplastics emerge as a hotspot for dibutyl phthalate sources in rivers and oceans: Leaching behavior and potential risks.

Dibutyl phthalate (DBP) as a plasticizer has been widely used in the processing of plastic products. Nevertheless, these DBP additives have the potential to be released into the environment throughout the entire life cycle of plastic products. Herein, the leaching behavior of DBP from PVC microplastics (MPs) in freshwater and seawater and its potential risks were investigated.

Aging behavior and leaching characteristics of microfibers in landfill leachate: Important role of surface mesh structure.

Mesh-structured films formed by the post-processing of microfibers improves their permeability and dexterity, such as disposable masks. However, the aging behavior and potential risks of mesh-structured microfibers (MS-MFs) in landfill leachate remain poorly understood. Herein, the aging behavior and mechanisms of MS-MFs and ordinary polypropylene-films (PP-films) microplastics, as well as their leaching concerning dissolved organic matter (DOM) in landfill leachate were investigated.

Immobilization mechanisms of Sr(II), Ni(II), and Cd(II) on glomalin-related soil protein in mangrove sediments at the microscopic scale.

Glomalin-related soil protein (GRSP) is a significant component in the sequestration of heavy metal in soils, but its mechanisms for metal adsorption are poorly known. This study combined spectroscopic data with molecular docking simulations to reveal metal adsorption onto GRSP's surface functional groups at the molecular level. The EXAFS combined with FTIR and XPS analyses indicated that the adsorption of Cd(II), Sr(II), and Ni(II) by GRSP occurred mainly through the coordination of -OH and -COOH groups with the metal.

Enhanced Cr(VI) stabilization by terrestrial-derived soil protein: Photoelectrochemical properties and reduction mechanisms.

Glomalin-related soil protein (GRSP) is a stable iron-organic carbon mixture that can enhance heavy metal sequestration in soils. However, the roles of GRSP in the transformation and fate of Cr(VI) have been rarely reported. Herein, we investigated the electrochemical and photocatalytic properties of GRSP and its mechanisms in Cr(VI) adsorption and reduction.

Centennial-scale source shift in potentially toxic metal(loid)s in Yangtze River.

Estuarine sedimentation is an important historical record of potentially toxic metal (PTM) emissions from human activities that can be used to improve environmental management. However, the contribution of different human activities to PTM deposition has not been accurately estimated, and their coupled relationship with riverine organic matter is typically not considered. In this study, we reconstruct the century-scale PTM depositional history of sediment cores from the Yangtze Grand Delta.

Iron plaque formation and its influences on the properties of polyethylene plastic surfaces in coastal wetlands: Abiotic factors and bacterial community.

Iron (Fe) plaques in coastal wetlands are widely recognized because of their strong adsorption affinity for natural particles, but their interaction behaviors and mechanisms with plastics remain unknown. Through laboratory incubation experiments, paired with multiple characterization methods and microbial analysis, this work focused on the characteristics of Fe plaques on low-density polyethylene plastic surfaces and their relationship with environmental factors in coastal wetlands (Mangrove and Spartina alterniflora soil). The results showed that iron plaques increased the adhesive force of the plastic surface from 65.

Change in glomalin-related soil protein along latitudinal gradient encompassing subtropical and temperate blue carbon zones.

Glomalin-related soil protein (GRSP), an abundant and eco-friendly bioproduct associated with arbuscular mycorrhizal fungi (AMF), contributes significantly to the soil particle aggregation and carbon sequestration. Although much research has been conducted on the storage of GRSP at different spatio-temporal scales in terrestrial ecosystems. However, the deposition of GRSP in large-scale coastal environments has not been revealed, which hinders an in-depth understanding of GRSP storage patterns and environmental controls, and this knowledge gap has become one of the key uncertainties in understanding the ecological functions of GRSP as blue carbon components in coastal environments.

Occurrence and Distribution of Tetrabromobisphenol A and Diversity of Microbial Community Structure in the Sediments of Mangrove.

The occurrence and distribution characteristics of tetrabromobisphenol A (TBBPA) and its relationship with microbial community diversity in different mangrove sediments need further investigation. The results of this study indicated levels of TBBPA in mangrove sediments from the Zhangjiang Estuary (ZJ), Jiulongjiang Estuary (JLJ), and Quanzhou Bay (QZ) in Southeast China ranging from 1.80 to 20.

Sequestration of strontium, nickel, and cadmium on glomalin-related soil protein: Interfacial behaviors and ecological functions.

Glomalin-related soil protein (GRSP) is a widespread recalcitrant soil protein complex that promotes the immobilization of metals in soils. Herein, we combined indoor simulation and field investigation to reveal the interfacial behaviors and ecological functions of GRSP to the three typical metals (Sr(II), Ni(II), and Cd(II)). The kinetic and isotherm data suggested that GRSP had a strong ability to adsorb the metals, which was closely related to the Hard-Soft-Acid-Base theory and the film diffusion mechanisms.

Stimulation of oxalate root exudate in arsenic speciation and fluctuation with phosphate and iron in anoxic mangrove sediment.

Mutual transformations of rhizospheric arsenic (As) in pollution-prone mangrove sediments affected by root exudate oxalate were simulated. This study focuses on the effect of oxalate on As release, mobilization, and phase speciation associated with P and Fe was examined under anoxic conditions in time-dependent changes. Results showed that oxalate addition significantly facilitated As-Fe-P release from As-contaminated mangrove sediments.

Uncovering the disposable face masks as vectors of metal ions (Pb(Ⅱ), Cd(Ⅱ), Sr(Ⅱ)) during the COVID-19 pandemic.

The demand for disposable face masks (DFMs) increased sharply in response to the COVID-19 pandemic. However, information regarding the underlying roles of the largely discarded DFMs in the environment is extremely lacking. This study focused on the pristine and UV-aged DFMs as vectors of metal ions (Pb(Ⅱ), Cd(Ⅱ), and Sr(Ⅱ)).

Variation of glomalin-metal binding capacity in 1 m soil profiles from mangrove forests to mudflat and affected factor analysis.

Glomalin-related soil protein (GRSP) plays an important role in soil metal sequestration in coastal wetlands. Additionally, it can release dissolved organic matter (GDOM) in water-soaked condition. The purpose of this study was to clarify the variation of GRSP's heavy metal immobilisation capacity at soil profiles of coastal wetland, and explore the compositional characteristics of GDOM and its influence on the heavy metals' environmental behaviour.

Phenolic root exudates enhance Avicennia marina tolerance to cadmium under the mediation of functional bacteria in mangrove sediments.

This study was carried out to demonstrate the mechanism of phenolic root exudates affecting microbial-mediated cadmium (Cd) speciation transformation thus enhancing the Avicennia marina tolerance to Cd. A rhizo-box experiment was conducted including eight treatments with four Cd levels (0, 1, 2, and 4 mg Cd kg) and two phenol levels (0, 15 mg kg). The results showed that the addition of phenols increased the pH, reduced the number of iron-reducing bacteria (IRB) and sulfur-oxidizing bacteria (SOB) in the rhizosphere sediments, meanwhile promoted the transformation of Cd to low activity speciation.

Spatial heterogeneity in chemical composition and stability of glomalin-related soil protein in the coastal wetlands.

GRSP is widely distributed in coastal wetlands, and there is a tendency for it to degrade with increasing burial depth. However, the dynamic changes in the chemical composition and stability of GRSP during the burial process are still unclear. The purpose of this study is to clarify the chemical composition and accumulation characteristics of GRSP during the burial process in the Zhangjiang estuary.

Extraction and purification of glomalin-related soil protein (GRSP) to determine the associated trace metal(loid)s.

Glomalin-related soil protein (GRSP) is recalcitrant compound in the soil and sediment and plays a crucial role in metal transportation. However, potential metal speciation changes during GRSP extraction remain unreported. Here, a feasible GRSP extraction and purification procotol is described for robust determination of GRSP-bound metal(loid)s.

Immobilization of lead(Ⅱ) and zinc(Ⅱ) onto glomalin-related soil protein (GRSP): Adsorption properties and interaction mechanisms.

Glomalin-related soil protein (GRSP), a microbial product that can be used as a bioflocculant, is critical to metal sequestration in the ecosystem. However, the relationship between GRSP and heavy metal has not been well explored. In this study, the adsorption behaviors and mechanisms of Pb(II) and Zn(II) ions on GRSP were investigated.

Post COVID-19 pandemic: Disposable face masks as a potential vector of antibiotics in freshwater and seawater.

With the outbreak and widespread of the COVID-19 pandemic, large numbers of disposable face masks (DFMs) were abandoned in the environment. This study first investigated the sorption and desorption behaviors of four antibiotics (tetracycline (TC), ciprofloxacin (CIP), sulfamethoxazole (SMX), and triclosan (TCS)) on DFMs in the freshwater and seawater. It was found that the antibiotics in the freshwater exhibited relatively higher sorption and desorption capacities on the DFMs than those in the seawater.

Release of sediment metals bound by glomalin related soil protein in waterfowls inhabiting mangrove patches.

Glomalin-related soil protein (GRSP) has received extensive attention due to its ability to immobilize metals in the environment. However, whether it can enter the food chain through digestion is still unclear. Mangroves occupy the transition zone between the sea and land, have important ecological functions.

Monitoring particulate composition changes during the flocculation process using polarized light scattering.

Monitoring the particulate composition changes during the flocculation process is still challenging for the research community. We use an experimental setup based on polarized light scattering to measure the polarization states of the scattered light of the individual particles. We build a classifier based on the support vector machine and feed it with the measured parameters.

A comparative study of sediment-bound trace elements and iron-bearing minerals in S. alterniflora and mudflat regions.

Elevated sediment-bound trace elements and iron-bearing minerals in intertidal habitats have been drawing more attention, but there is rarely a comparative study assessing these features between halophyte plants habitat and mudflats. In this paper, sediment samples were collected in S. alterniflora and the corresponding mudflat at 7 typical intertidal habitats (Chongming, Xiapu, Yueqing, Yunxiao, Zhanjiang, Beihai, and Zhuhai) from north to south of China, respectively.