Publications by authors named "Xisheng Tai"

To understand the pollution status, distribution characteristics, and pollution sources of soil heavy metals in tourist cities in northwest China, the soil content of heavy metals As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn in the main areas of Dunhuang City was collected and analyzed. The soil heavy metal pollution level was quantitatively evaluated by the methods of the geo-accumulation index and improved Nemerow pollution index, and the sources of heavy metal pollution were quantitatively analyzed using cluster analysis and the positive matrix factorization (PMF) model. The contribution rate of each pollution source to ecological risk was determined by combining the PMF model and comprehensive ecological risk index.

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Article Synopsis
  • - Assessments of heavy metal pollution in farmland soils in the Yellow River Basin from 2000 to 2023 revealed that, while average levels were generally below safety standards, certain metals like Cd, As, and Zn exceeded their acceptable limits, with Cd being the most concerning.
  • - The study classified pollution levels with Hg and Cd as moderately polluted, while Cu and Pb were slightly polluted, indicating varying degrees of contamination among the metals.
  • - Main pollution sources for heavy metals were identified as traffic-industrial, natural-agricultural, industrial-natural, and agricultural-industrial, with significant health risks associated mainly with As and Cd, prompting recommendations for targeted control measures.
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Source-specific risk apportionment for soil potentially toxic metals (PTMs) is of great significance for contamination prevention and risk management in urban environments. Eighty-five urban soil samples were obtained from an oasis-tourist city, China and examined for eight PTMs (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn). The pollution levels, sources, and ecological risk of soil PTMs were quantified, and their source-specific ecological and human health effects were also estimated using the multi-proxy approaches.

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  • This study analyzed soil contamination near the Jingyuan coal-fired power plant, focusing on potentially toxic elements (PTEs) like As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn, by comparing urban and agricultural samples.
  • Results indicated that most soil metal concentrations exceeded regional background levels, with notable contamination from Cd, Cr, Ni, and Pb, while Hg showed significant spatial variability, suggesting a strong impact from human activities.
  • Source analysis identified that PTEs in urban soils mainly originated from traffic and coal combustion, as well as industrial activities, with specific contribution rates determined through different analytical models.
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Identifying the contamination and sources of potentially toxic elements (PTEs) in road-dust sediment (RDS) and the surrounding greenspace soil of urban environments and understanding their ecological-health risks are important for pollution management and public health. The contamination characteristics, ecological and probabilistic health risks, and source apportionment of eight PTEs (Cd, Pb, Cr, Cu, Ni, As, Zn, and Hg) in the Yellow River Custom Tourist Line of Lanzhou, which is the largest open urban riverfront scenic park in China, were investigated. The results showed that all the RDS PTE mean concentrations exceeded their soil background values, whereas for the surrounding greenspace soils, the concentrations of the PTEs, except for Cr and Ni, were also higher than their local background levels.

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In order to investigate the contamination levels of dust and its surrounding green land soil heavy metal pollution and potential ecological and health risks in the scenic areas of urban waterfront parks, the gardens, squares, and theme parks of the Yellow River Custom Tourist Line in Lanzhou were selected as the research area, using 27 dust samples and 26 soil samples from its surrounding green lands. The contamination characteristics and potential ecological risks of eight heavy metals (Cr, Ni, Cu, Zn, As, Cd, Hg, and Pb) were evaluated using the geo-accumulation index (), single-factor pollution index (), Nemerow integrated pollution index (), and improved potential ecological risk index (RI). The human health risk assessment was also evaluated using the exposure risk model.

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Heavy metals are considered to be one of the main sources of soil contamination. In this study, three tolerant bacteria were isolated from the heavy metal-contaminated soil in mining area, and immobilized bacteria were constructed using corn straw as the carrier. The combined remediation effect of immobilized bacteria and alfalfa in pot experiments was explored in heavy metal-contaminated soil.

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The prevalence of antibiotic resistance genes (ARGs), owing to irrigation using untreated swine wastewater, in vegetable-cultivated soils around swine farms poses severe threats to human health. Furthermore, at the field scale, the remediation of such soils is still challenging. Therefore, here, we performed field-scale experiments involving the cultivation of Brassica pekinensis in a swine wastewater-treated soil amended with composted pig manure, biochar, or their combination.

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Article Synopsis
  • Biochar creates an ideal environment for microorganisms, influencing heavy metal bioavailability during composting, specifically in pig manure.
  • The study included experiments with no treatment, microbiological inoculation alone, and microbiological inoculation with biochar, revealing that biochar significantly decreased the bioavailability of heavy metals like Cu, Zn, Pb, and Cr.
  • Key microorganisms identified included Debaryomyces, which may help in reducing Cr availability, as well as Bacillus and Fusarium, which assist in lowering Zn levels. The findings support using microbial inoculum and biochar to minimize heavy metal contamination during composting.
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Pseudarthrobacter sulfonivorans strain Ar51 can degrade crude oil and multi-substituted benzene compounds efficiently at low temperatures. However, it cannot degrade hydroquinone, which is a key intermediate in the degradation of several other compounds of environmental importance, such as 4-nitrophenol, g-hexachlorocyclohexane, 4-hydroxyacetophenone and 4-aminophenol. Here we co-expressed the two subunits of hydroquinone dioxygenase from Sphingomonas sp.

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Heavy metal (HM) pollution is a severe and common environmental problem in mining area soil. It is imperative to understand the micro ecological characteristics of mining area soil for HM contaminated soil remediation. This study described the effects of HM pollution level and soil physical and chemical parameters on microbial diversity.

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A Gram-staining-positive and aerobic coccus with the ability to degrade petroleum bacterium, designated Y42, was isolated from the Lenghu oil field located in the northern margin of the Qaidam Basin. Phylogenetic and signature nucleotides analyses revealed that strain Y42 belongs to the genus Planococcus. The multiple sequence alignments of 16S rRNA and housekeeping genes showed that strain Y42 formed a distinct lineage with the other Planococcus clade.

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Actinobacteria are known for their metabolic potential of producing diverse secondary metabolites such as antibiotics. Actinobacteria also playimportant roles in biogeochemical cycling and how soils develop. However, little is known about the effect of the vegetation type on the actinobacterial community structures in soils from arid regions.

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As a glacier retreats, barren areas are exposed, and these barren areas are ideal sites to study microbial succession. In this study, we characterized the soil culturable bacterial communities and biochemical parameters of early successional soils from a receding glacier in the Tianshan Mountains. The total number of culturable bacteria ranged from 2.

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The aim of this study was to survey the response of the microbial community to crude oil and the diversity of alkane hydroxylase (alkB) genes in soil samples from the Qinghai-Tibet Plateau (QTP). The enrichment cultures and clone libraries were used. Finally, 53 isolates and 94 alkB sequences were obtained from 10 pristine soil samples after enrichment at 10 °C with crude oil as sole carbon source.

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Heavy-ion beams, possessing a wide mutation spectrum and increased mutation frequency, have been used effectively as a breeding method. In this study, the heavy-ion beams generated by the Heavy-Ion Research Facility in Lanzhou were used to mutagenize Aspergillus terreus CA99 for screening high-yield lovastatin strains. Furthermore, the main growth conditions as well as the influences of carbon and nitrogen sources on the growth and the lovastatin production of the mutant and the original strains were investigated comparatively.

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