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The aerobic bacteria Acidimicrobiaceae, Hyphomonas and the nonoil efficient Peptoccaceae disappeared in the process of salinization and oil pollution. Lactobacilliceae can ferment carbohydrate, fatty acid or ester to produce lactic acid, acetic acid and fumaric acid to provide metabolic substrate for other microorganisms. The above results showed that sensitive microorganisms were easy to be affected by pollution to indicate soil conditions, while tolerant microorganisms could potentially use oil to achieve bioremediation. The soil properties and microbial results provided data support and theoretical basis for further understanding the pollution mechanism of oil and salinization combined stress on soil.Cadmium (Cd) is harmful to plant growth and can be easily transferred from soil to plants. Plant cell wall plays important role in preventing Cd from entering cells. Salicylic acid (SA) mediated defense response increases plant resistance to heavy metals. In this study, all tomato seedlings were pre-treated with 100 μM SA for 3 d, then seedlings were used to analyze the role of SA in regulating plant cell wall resistance to Cd stress. The results showed that exogenous SA significantly reduced Cd accumulation in tomato plants and changed Cd distribution. By analyzing the cell wall composition, it was found cellulose, hemicellulose, pectin, and lignin were induced by SA. Interestingly, the content of Cd in pectin decreased by SA pretreatment, however it was increased in cellulose. Gene expression analysis showed SA up-regulated the expression level of lignin and cellulose synthase genes, but down-regulated the expression of pectin methylesterase related genes. In addition, SA down-regulated the activity of pectin methylesterase. These results indicated that SA pretreatment up-regulated cell wall polysaccharide synthesis and related gene expression to thicken the cell wall and block Cd from passing through. Furthermore, SA decreased pectin methylesterase activity and content to reduce cell wall Cd accumulation and change the Cd partition ratio.Meiobenthos has been considered as an excellent tool for biomonitoring assessment. Elevated temperature and oil pollution are considered as the most pervasive aspects of global environmental changes and matter of concern for contemporary society. Presently, very limited information is available about the synergistic effect of these stressors on meiobenthic community structure and tolerance potential from tropical intertidal environment. Here, we assessed their impacts on meiobenthic community by conducting a 60 days long benthocosm experiment selecting three sets of temperature (25°, 30° and 35 °C) and two sets of diesel oil (low and high) combinations. Gradual changes in their community composition were revealed discernibly with exposures to both the disturbances after 30 and 60 days of experimental period. Diversity profiles for the nematodes were less affected, but copepods showed a graded response of decreasing density with increasing dose of both the stressors. Other meiobenthic taxa such as halacarid mieeders in treated sediments. Overall, elevated temperature together with diesel oil contamination were found to alter species dynamics within shallow intertidal meiobenthic communities, which might have significant Armageddon on benthic ecosystem functioning.In this paper, earthworms (Eisenia fetida) were exposed to sublethal doses of dichlorvos (spiked concentration of 0.1, 1.0, 10 mg/kg) in soil for 14 days, the metabolomics and activities of cytochrome P450 (CYP) isoenzymes (CYP1A2, CYP2C9 and CYP3A4) of earthworms were analyzed aiming to identify sensitive biomarkers and reveal possible mode of toxic action. The results showed that CYP1A2 and CYP2C9 activity appeared to be more sensitive than CYP3A4 activity in response to dichlorvos, and that metabolic responses based on the metabolomics depended on both of the length of exposure and exposure dose. Malate, ornithine, glucose, inosine, myo-inositol and some amino acids (glutamine, tryptophan, phenylalanine, tyrosine, leucine, histidine, glutamate, lysine) and CYP isozenzymes may be biomarkers to reveal the toxic effect of dichlorvos on earthworms. Compared to controls, when dichlorvos dose reached 1.0 and 10 mg/kg on day 14, glucose and ornithine increased significantly, malate and some amino acids (glutamine, tryptophan, phenylalanine, tyrosine, leucine) decreased significantly, and activities of CYP1A2 and CYP2C9 were inhibited significantly. The current results suggested that 1.0 and 10 mg/kg dichlorvos for 14 days of exposure blocked energy metabolism, disordered Krebs cycle, interfered amino acids metabolism and evoked toxic effects on earthworms.Degradation solutions containing atrazine need to be further purified before they are discharged into the aquatic environment. With the objectives of evaluating removal capacity of the microalga Chlorella sp. toward atrazine in degradation solutions and toxicity of the degradation products, we investigated the removal efficiency (RE) and bioaccumulation of atrazine in the microalgae after an 8 d exposure to diluted degraded solutions containing 40 μg/L and 80 μg/L of atrazine as well as degradation products in the present study. Moreover, pure atrazine solutions with similar concentrations were simultaneously inoculated with the microalgae in order to distinguish the influence of the products. The photocatalytic degradation results showed that 31.4% of atrazine was degraded after 60 min, and three degradation products, desisopropyl-atrazine (DIA), desethyl-atrazine (DEA), and desethyl-desisopropyl-atrazine (DEIA) were detected. After an 8-d exposure, 83.0% and 64.3% of atrazine were removed from the degraded e application of microalgae in herbicide wastewater treatment and understanding algal removal of atrazine in natural aquatic environment.Dissolved organic matter extracted from compost tea, can be regarded as alternatives to inorganic fertilizers as well to be used as a washing agent for heavy metal polluted soil. However, the composition and quality of compost tea produced under different extraction time are still unknown. The objective of the current study was set to explore the influence of different extraction time (i.e., 6, 12, and 24 h) on the composition, quality, and copper binding capacity of compost tea originated from pig manure compost. The results indicated that the extraction time obviously influenced the phenolic, aromatic carboxylic, and polycyclic aromatic groups of compost tea. In addition, the compost tea undergo the shorter extraction time (i.e., 6 and 12 h) contained more protein and humic-like compositions. Among the all treatments tested herein, the compost tea produced from 12 h extraction time obviously exhibited higher aromaticity, molecular weight, and humification degree than other two treatments. The highest stability constant value (log KM) was observed for the shortest extraction time, i.e., 6.08. According to the quality measures and copper binding capability, shorter extraction times (i.e., 6 and 12 h) would be suggested for compost tea production from pig manure compost.Selenium (Se)-enriched wheat can be improved by altering Se sources and selecting wheat cultivars. Such improvement can affect subcellular distribution and speciation of Se in wheat. Thus, a pot experiment was conducted to investigate Se uptake and distribution when Se was applied as selenite or selenate at low and high rates (1 and 10 mg kg-1, respectively). P-gp modulator Moreover, Se's impact on the grain and biomass yield of eight wheat cultivars was also investigated. The subcellular distribution and speciation of Se were also explored to elucidate Se metabolism and micro-distribution pattern in wheat. Results showed that biomass and grain yield were decreased with the application of both selenite and selenate in almost all the cultivars, regardless of the Se rate. Application high Se rate resulted in a significant (p less then 0.05) decrease in grain yield and biomass compared with low rate of Se. Compared with the low rate of selenite application, the grain and the biomass yield of ZM-9023 significantly (p less then 0.05) increased by about 15% for low rate of selenate application. In addition, both selenite and selenate treatment increased the uptake of Se in each part of wheat, compared with the control. Selenium was mostly accumulated in the grain and root of wheat under selenite treatment, while more Se accumulation was found in leaves and straw for selenate application. Further investigation on the subcellular distribution of Se showed that the proportion of Se in soluble fraction was significantly (p less then 0.05) higher in wheat leaves than that in organelle fraction and cell walls (46%-66%). Meanwhile, Se6+ was the main species found in soluble fraction, whereas SeMet and MeSeCys were the species predominantly stored in organelle fraction. In conclusion, wheat cultivar ZM-9023 is the most Se-rich potential cultivar, and the isolation of Se in the soluble fraction plays an important role in Se tolerance and accumulation.Ammonia has been of concern for its high toxicity to aquatic species and frequent detection in waters worldwide. This study calculated the national aquatic life criteria for ammonia in China. The temporal and spatial distributions were investigated and the multi-tier ecological risks were assessed for ammonia and un-ionized ammonia (NH3) during 2014-2018 based on a total of 18989 ammonia monitoring data from 110 monitoring sites in seven river basins. The sensitivity comparison of different species taxa to ammonia showed that Perciformes fish should be listed as a priority protected species in the derivation of ammonia criteria. The participation of introduced aquaculture species have no significant impact on the final criteria values (t-test, p > 0.05). The final criterion maximum concentration (CMC) and criterion continuous concentration (CCC) were 10.24 and 3.31 mg/L for ammonia (pH 7.0 and 20 °C). The interannual variation showed that decreasing trends were observed for ammonia and NH3 pollutions in the past five years. However, the increasing trends were observed for ammonia in Liao River basin, for NH3 in Yangtze River and Pearl River basins (2014-2018). The significant seasonal and geographical differences of ammonia and NH3 pollution were found. Moreover, the pollutions of ammonia and NH3 in some monitoring points of Huai River, Yellow River and Songhua River basins at the provincial borders were significant. The result of ecological risk assessment showed that the average exceedance probability for 5% affected species by NH3 in long-term exposure was 28.96% in the past five years.Limited information is available about the bio-methylation of inorganic mercury (iHg) under aerobic conditions. In this study, two γ-proteobacteria strains (P. fluorescens TGR-B2 and P. putida TGR-B4) were obtained from the soil of The Three Gorges Reservoir (TGR), demonstrating effective aerobic transformation capacities of iHg into methylmercury (MeHg). Based on periodical changes in soil oxygen content of the TGR, a culture system was established, in which 300 ng Hg (II) L-1 and O2 were set at 7%, 14%, and 21%, respectively. Results indicated that the two strains differed significantly in bacterial growth rate and MeHg production. The kinetic model of MeHg showed typical characteristics of a "two-staged" process The first stage was dominated by bio-methylation, which was shown by increasing of net MeHg content. Moreover, the second stage was dominated by bio-demethylation, which decreased net MeHg content. Thus, we hypothesized that the mechanism of aerobic bacterial iHg bio-methylation (1) should inefficiency compared to anaerobic bacteria i.