Publications by authors named "Ziyan Qian"

Extracellular polymeric substances (EPS) are an important medium for communication and material exchange between iron-oxidizing bacteria and the external environment and could induce the iron (oxyhydr) oxides production which reduced arsenic (As) availability. The main component of EPS secreted by iron-oxidizing bacteria (Ochrobactrum EEELCW01) was composed of polysaccharides (150.76-165.

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Iron-oxidizing bacteria (FeOB) could oxidize Fe(II) and mediate biomineralization, which provides the possibility for its potential application in arsenic (As) remediation. In the present study, a strain named isolated previously, was inoculated into paddy soils to investigate the effect of FeOB inoculation on the As migration and transformation in paddy soils. The results showed that inoculation of sp.

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The microbe-driven iron cycle plays an important role in speciation transformation and migration of arsenic (As) in soil-rice systems. In this study, pot experiments were used to investigate the effect of bacterial iron (Fe) reduction processes in soils on As speciation and migration, as well as on As uptake in soil-rice system. During the rice growth period, pH and electrical conductivity (EC) in soil solutions initially increased and then decreased, with the ranges of 7.

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The effects of electron shuttles (biochar/anthraquinone-2,6-disulphonate (AQDS)) on the process of the Shewanella oneidensis MR-1-induced As(V)-adsorbed ferrihydrite reduction were studied. The results showed that biochar could stimulate Fe(Ⅱ) and As release during the ferrihydrite bioreduction. After the addition of biochar, more dissolved organic matter (DOM) can be consumed as an electron donor to promote the metabolism of microorganisms by the fluorescence excitation-emission matrix spectra analysis.

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Cadmium contamination in paddy soils has aroused increasing concern around the world, and biochar has many positive properties, such as large specific surface areas, micro porous structure for the heavy metal immobilization in soils. However there are few studies on sulfur-iron modified biochar as well as its microbiology effects. The purpose of this study was to evaluate the Cd immobilization effects of sulfur or sulfur-iron modified biochar and its related microbial community changes in Cd-contaminated soils.

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Arsenic contamination in paddy soils has aroused global concern due to its threats to food security and human health. Biochar modified with different iron materials was prepared for arsenic (As) immobilization in contaminated soils. Soil incubation experiments were carried to investigate the effects of biochar modified with Fe-oxyhydroxy sulfate (Biochar-FeOS), FeCl (Biochar-FeCl), and zero-valent iron (Biochar-Fe) on the pH, NaHCO-extractable As concentrations, and the As fractions in soils.

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