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The Jialing River is one of the largest tributaries of the Yangtze River and has the largest drainage area. Nickel (Ni) is a one of the most serious heavy metal contaminants in the downstream section of the Jialing River as a result of the prosperity of nearby chemical, electronic and mining industries. In the present work, sediment quality guidelines (SQGs), a Community Bureau of Reference (BCR) sequential extraction and the diffusive gradients in thin films (DGT) technique were applied to evaluate the environment risk, fractions and remobilization of Ni in the downstream Jialing River. The results indicated that the average total concentration of Ni (54.7 mg kg−1) at all sites was higher than the background values of soil in China and Sichuan (26.9 and 35.8 mg kg−1, respectively). Environment risk assessment with four types of SQG values found that at three sites, the Ni concentration was over two high guideline values (probable effect concentration, PEC; effect range median, ERM), indicating that Ni may frequently pose a threat to the local aquatic ecosystem. The DGT results showed that C DGT -Ni had an inverse variation trend with C DGT -Fe and presented a significant increasing trend at the bottom of the DGT probes. Flux results revealed that sediments at S1, S2 and S3 were the source for Ni release across the sediment-water interface (SWI), and only S4 was a sink for Ni. Two further studies found that C DGT -Ni presented a significant negative correlation with C DGT -Fe. In addition, the "hotspot" of C DGT -Ni at the bottom correlated well with the "dark area" of C DGT -S. These results indicated that Fe and S were factors that mitigated the release of Ni in the sediments. Image 1 • Ni may frequently pose an environment risk in the study area. • Ni was mainly bound to the residual fraction of the sediment. • The remobilization of Ni in the sediment was related to the release of Fe and S. [ABSTRACT FROM AUTHOR]

As a bottom-up approach, the effectiveness of the environmental information transparency policy hinges on a broad societal ecosystem, including elements such as the active mass media and the robust civil society. However, due to the lack of public participation and accountability mechanisms, it is still doubtful whether the Chinese environmental transparency program promoted corporate pollution mitigation efforts. In this study, we investigated the impacts of the Environmental Information Disclosure (EID) program, an important Chinese environmental transparency program, on corporate mitigation investments, by using the 2012 Chinese Private Enterprise Survey. Our Tobit-IV model provides robust evidence that transparency policy exerts significant influences only on non-politically connected polluters, while, by contrast, politically connected firms are less susceptible to the EID program. We suggest that the community should be empowered to deter the shelter effects of local governors to the connected firms, which deteriorate the effectiveness of the transparency program. Image 1 • We investigated the impacts of the Chinese Environmental Information Disclosure (EID) program. • EID exerts significant influences only on non-politically connected polluters, while, by contrast. • Politically connected firms are less susceptible. • The community should be empowered to deter the pollution shelter effects. [ABSTRACT FROM AUTHOR]

Nonpoint source pollution (NPSP) from human production and life activities causes severe destruction in river basin environments. In this study, three types of sediment samples (A, NPSP tributary samples; B, non-NPSP mainstream samples; C, NPSP mainstream samples) were collected at the estuary of the NPSP tributaries of the Jialing River. High-throughput sequencing of the fungal-specific internal transcribed spacer (ITS) gene region was used to identify fungal taxa. The impact of NPSP on the aquatic environment of the Jialing River was revealed by analysing the community structure, community diversity, and functions of sediment fungi. The results showed that the dominant phylum of sediment fungi was Rozellomycota, followed by Ascomycota and Basidiomycota (relative abundance > 5%). NPSP caused a significant increase in the relative abundances of Exosporium, Phialosimplex, Candida, Inocybe, Tausonia, and Slooffia, and caused a significant decrease in the relative abundances of Cercospora, Cladosporium, Dokmaia, Setophaeosphaeria, Paraphoma, Neosetophoma, Periconia, Plectosphaerella, Claviceps, Botrytis, and Papiliotrema. These fungal communities therefore have a certain indicator role. In addition, NPSP caused significant changes in the physicochemical properties of Jialing River sediments, such as pH and available nitrogen (AN), which significantly increased the species richness of fungi and caused significant changes in the fungal community β-diversity (P < 0.05). pH, total phosphorus (TP), and AN were the main environmental factors affecting fungal communities in sediments of Jialing River. The functions of sediment fungi mainly involved three types of nutrient metabolism (symbiotrophic, pathotrophic, and saprotrophic) and 75 metabolic circulation pathways. NPSP significantly improved the pentose phosphate pathway, pentose phosphate pathway, and fatty acid beta-oxidation V metabolic circulation pathway functions (P < 0.05) and inhibited the chitin degradation to ethanol, super pathway of heme biosynthesis from glycine, and adenine and adenosine salvage III metabolic circulation pathway functions (P < 0.05). Hence, NPSP causes changes in the community structure and functions of sediment fungi in Jialing River and has adversely affected for the stability of the Jialing River Basin ecosystem. [ABSTRACT FROM AUTHOR]

Fertilizers are important for agricultural production because they can effectively promote crop productivity. However, long-term fertilization can cause heavy metal accumulation in soils and crops. This study utilized sequential extraction, the diffusive gradient in the thin films (DGT) technique and risk assessment models to estimate the effects of the longest long-term fertilization (38 years) in China on cadmium (Cd) and arsenic (As) accumulation in soils. The treatments included no fertilization (CK); inorganic nitrogen, phosphorus, and potassium fertilization (NPK); manure fertilization (M); and NPK plus M cofertilization (NPKM). The results indicated that the soils treated with NPKM, M and NPK had significantly increased total and available concentrations of Cd and As after 38 years of long-term fertilization. Cd mainly originates from cattle manure, while As originates from phosphate fertilizer. Sequential extraction results indicated that the application of manure increased the acid/exchangeable fraction (F1) and organic matter-bound fraction (F3) of Cd and As. The risk assessment results showed that the environmental risks of both Cd and As increased during long-term fertilization, and Cd contamination in the soil was at a moderate-high level, while As remained at a relatively low level. According to the calculations of the maximum numbers of years of soil productivity and rice production, Cd was labile and accumulated in the soils, and As was more labile than Cd in terms of accumulating in rice, indicating that the true risk from As in rice is higher than that from Cd. Controlling the heavy metals in fertilizers, mitigating effective amendments, and identifying plant types that accumulate low amounts of contaminants may be good choices for cleaner crop production. [Display omitted] • 38 years long-term fertilization leaded to a significant increment of cadmium and arsenic in soils. • Manure and phosphate fertilizer were the sources for cadmium arsenic input. • Cadmium and arsenic posed a medium-strong and low environmental risk to the farmland respectively. • Cadmium tended to accumulate in soil and arsenic was labile to accumulate in rice seeds. [ABSTRACT FROM AUTHOR]