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Phosphorus (P) availability in soil is often limited, posing a challenge for sustainable agricultural production. Phosphate solubilizing microorganisms (PSMs) have emerged as a promising biological approach to enhance soil P availability while minimize negative environmental impacts. Exploring the impact of PSMs on increasing soil available P is crucial for optimizing the utilization of insoluble P in soil and promoting sustainable agricultural practices. In this article, we provide a comprehensive review on the dynamics of soil available P, including its input, loss and transformation processes. Additionally, we draw a conclusion about how PSMs increase the availability of P in soil, including solubilizing inorganic P (Pi) and organic P (Po) by secreting substances such as protons, organic acids, inorganic acids, exopolysaccharides, hydrogen sulfide, siderophores and phosphatases. Notably, the factors influencing the P solubilizing activity of PSMs in soil are thoroughly discussed. Moreover, practical applications of PSMs for increasing soil P availability are summarized. Future research should focus on exploring novel PSM isolates, conducting long-term field experiments to assess the effects and potential risk of PSMs under diverse conditions, and investigating synergistic approaches with other P activators or beneficial microorganisms. This review will advance our understanding of PSMs and their practical application, enabling their widespread adoption in agricultural systems. [ABSTRACT FROM AUTHOR]

In this study, NiFe2O4 and Ag0.1Ni0.95Fe2O4 were successfully prepared by the sol–gel method and applied to catalyze ozone for dibutyl phthalate (DBP) degrading. The synthesized catalysts were characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, and vibrating sample magnetometer. The removal efficiency was compared with different catalyst dosage, pH condition, and initial DBP concentration for the two catalysts. The results showed that the introduction of Ag0.1Ni0.95Fe2O4 enhanced the ozone decomposition and the utilization efficiency of ozone from 32.2% (ozone alone) to 56.5% and improved the degradation efficiency of DBP significantly. The two catalysts both presented good recycling performance. Furthermore, the scavenger test displayed DBP degradation by catalytic ozonation dominated by OH in this study. These insights into the catalytic ozonation mechanism on Ag0.1Ni0.95Fe2O4 will advance their practical application to the catalytic degradation of organic pollutants. [ABSTRACT FROM AUTHOR]

Aryl sulfonyl chlorides and sodium aryl sulfinates are proved to be powerful arylating agents for the C–C bonds formation through desulfitative cross-coupling reactions. These versatile compounds have also been widely utilized as aryl sulfonyl sources in the synthesis of aromatic sulfones. As evidenced in the literature, aryl sulfonyl chlorides and sodium aryl sulfinates are also promising sulfenylation agents for the efficient and practical construction of synthetically and medicinally important aryl thioethers (through the cleavage of their sulfur–oxygen and sulfur–chloride/oxygen-sodium bonds). In this focus review, we have summarized recent progress and developments in the direct sulfenylation of C–H bonds utilized the titled compounds with special emphasis on the mechanistic aspects of the reactions. [ABSTRACT FROM AUTHOR]

Twenty-one surface sediments collected from seven surroundings areas of Lake Taihu in two different years were analyzed for total mercury (THg) concentrations, physicochemical characteristics and speciation using a sequential extraction method to assess spatial distribution, sources, and potential ecological risk. Surface sediments from Lake Taihu contained elevated levels of Hg in two sampling years with THg levels ranging from 77 to 346 ng/g (mean 145 ng/g) in October 2010 and ranging from 122 to 573 ng/g (mean 266 ng/g) in November 2012, respectively. The mean THg concentrations in all studied surface sediments exhibited an increasing trend over time. The oxidizable fraction (F3) and residual fraction (F4) were the predominant Hg species in sediments, while more mobile Hg phases of acid-soluble fraction (F1) and reducible fraction (F2) made up less than 0.5% THg. Significant relationships were found between total organic carbon (TOC) and THg and geochemical speciation indicating an important role for organic matter in affecting distribution, mobility, and bioavailability of Hg in sediments. As evidenced by Hakanson's potential risk index the total ecological risk of Hg was low in the entire Lake Taihu in 2010 but considered moderate in Zhushan Bay, West Coast, and Meiliang Bay in 2012. These findings provide conservation managers with information needed to more effectively regulate the environment of Lake Taihu. [ABSTRACT FROM AUTHOR]

In recent years, the use of zero-valent iron (ZVI) coupled with microorganisms has attracted considerable attention for the removal of diverse contaminants from wastewater, and the performance of bio-ZVI systems under diverse conditions is of particular interest. This paper comprehensively reviews the recent developments related to (1) the effects of the iron surface area, operating conditions, coexisting ions, and contaminant concentrations on the performance of bio-ZVI systems; (2) the potential mechanisms of the major factors affecting the ZVI–microbe performance; and (3) the effects of ZVI on the characteristics of the microorganisms, including both enhancing and deteriorating effects. All these factors can have notable impacts, which are contaminant-specific and highly dependent on the removal mechanisms of the respective pollutants, and on the performance of the bio-ZVI system in terms of contaminant removal. Additionally, the stimulating effects of ZVI on the growth and diversity of microorganisms are reasonable considering the synergistic effects of the combined system on pollutant removal, although inhibitory effects of ZVI on bacterial activity have also been proposed. Based on these findings, further efforts should be made to establish feasible strategies to improve the engineering design and performance of integrated ZVI–microbe systems. [ABSTRACT FROM AUTHOR]

In this study, we investigated water sources of three typical plant species, i.e., Ginkgo biloba (Ginkgo biloba L.), Green soybean (Glycine max (L) Merr.), and Mulberry tree (Morus alba L.) in a rainy season by using a dual stable isotope approach (δ18O and δ2H). Potential water sources were divided into direct or internal (i.e. soil water at different depths) and indirect or external water sources (i.e. precipitation, river water and groundwater). The results indicated that the surface soil water δ18O and δ2H is enriched probably due to evaporation. Ginkgo biloba and Green soybean prefer using soil water from the upper soil layer (0–60 cm) and precipitation, and the Mulberry tree mainly used deep soil water (120-150 cm) and groundwater. The different water use strategies of the three plant species are likely to be determined by their different root distribution at the above correspondent soil depths. [ABSTRACT FROM PUBLISHER]

Soil samples were collected from three different ranks riparian soil profiles in a small river basin of Taihu area in China. The method of modified Hedley phosphorus sequential fraction was employed to characterize soil phosphorus fractions. The results showed that the riparian soil total phosphorus (TP) contents, organic phosphorus (OP) and inorganic phosphorus (IP) of the basin ranged from 234.98 to 542.29, 49.76 to 73.81, 161.17 to 492.54 mg kg−1, respectively. HCl-Pi, NaOH-Piand residual Piwere the major part of IP, accounting for 28, 28 and 26% of IP respectively, but NaHCO3-Piwas accounted for 18% of IP. Overall, the various forms of phosphorus, except for Residual P, had a decreasing trend with soils depth. The vertical distributions of TP and IP had same rank order (Riparian Hejiabang > Riparian wuxidang > Riparian Yincungang), while the opposite trend was observed for OP. Surface soils in Riparian Yincungang had lower SOM (soil organic matters):OP ratios than Riparian Wuxidang and Riparian Hejiabang, reflecting the higher probability of OP mineralization in uncultivated soils. Besides, there was significant correlation between phosphorus fractions and SOM, bulk density and capillary porosity. [ABSTRACT FROM PUBLISHER]

To study the effect of wastewater irrigation in pepper fields, this research analyzed the principle of the water vapor–heat–nitrogen coupling transport and the diurnal rule of root water/nitrate uptake dynamics in wastewater-irrigated pepper fields. In an outdoor experiment, the soil water content, negative pressure head, and temperature at depths of 10, 25, 40, 55, and 70 cm were measured hourly for 480 h in July 2013. The modified HYDRUS-1D code was used to analyze soil water and root water/nitrogen uptake dynamics. The numerical analyses provided insight into the diurnal movement of the soil water and root water/nitrogen uptake dynamics driven by the gradients of the pressure heads and temperatures. The measured and simulated data agree well with each other. When the original nitrate-nitrogen (NO3-N) content in the soil is high, additional wastewater irrigation will not increase the root uptake of NO3-N. Thus, excessive wastewater irrigation may cause groundwater nitrogen contamination. [ABSTRACT FROM AUTHOR]

Surface sediments were collected from the Yangtze River Estuary (YRE) in May 2012, August 2012, November 2012 and February 2013 to analyse the seasonal and spatial distributions of acid-volatile sulphide (AVS), simultaneously extracted metals (SEM) and the sediment toxicity. An optimised method was used for the AVS and SEM analysis and the results showed that the seasonal variations of AVS were positively correlated with changes in water temperature and the position of higher AVS was relatively fixed. The average of SEM was gradually increased from May 2012 to February 2013 and there were abnormally high values of SEMCuand SEMNiin the YRE. Concentrations of the five SEM components were in the following order: Cd < Pb < Cu ≈ Ni < Zn. The correlations among the concentrations of the five metals suggested that these metals in the sediments of the YRE did not have stable anthropogenic and/or natural origin. The mean values of AVS and SEM in the YRE were closer to those in the Huanghe Estuary and were lower than those in the Pearl River Estuary. The results of two sediment toxicity assessments showed that the sediments of most areas in the YRE had potential sediment toxicities, especially the Ni and Cu contamination. [ABSTRACT FROM PUBLISHER]