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Polycyclic aromatic hydrocarbons (PAHs) are hazardous and ubiquitous pollutants in the aquatic environment, and understanding the pollution characteristics and risk levels of PAHs is of great significance to the sustainable development of drinking water sources and drinking water safety. Hence, PAHs residues were measured qualitatively and quantitatively with solid-phase extraction-gas chromatography-mass spectrometry (SPE-GC-MS) in 33 water samples (including 22 groundwater and 11 surface water samples) of the drinking water sources in the Manzhouli and Xinyouqi areas of northeast Inner Mongolia, and assessments of the pollution level of PAHs and the health and ecological risks were carried out. The results showed that PAHs were detected in all 33 sampling points of Manzhouli drinking water sources, except for benzo[k] fluoranthene, benzo[a] pyrene, and dibenzo[a,h] anthracene, with detection rates ranging from 36.36% to 95.45%; the detection rates of the other 13 PAHs monomers were 100%. The detection range of

Composting plants are an important source of airborne fungi. At present, no research has been reported on differences in the types and abundance of escaped fungi in different working areas, which makes it very difficult to comprehensively assess the ecological health risks of the air in composting plants. In light of this situation, this study collected air samples from the composting, packaging, office, and downwind areas of the composting plants and used high-throughput sequencing technology to analyze and compare the biological diversity and community structure of airborne fungi in the four areas. The source of airborne fungi in offices and downwind areas was further traced. The results showed that the highest abundance and diversity of airborne fungi were found in the packing and composting areas of the composting plants. Ascomycota and Basidiomycota were two fungal phyla with the highest relative abundance in the four regions. Overall, the distribution of dominant fungal genera differed

In order to reveal the pollution characteristics and risk levels of DBPs in typical drinking water sources in Wuhan under the COVID-19 pandemic, 26 sampling sites were selected in typical drinking water sources in Wuhan.

Solid phase extraction (SPE) and high-performance liquid chromatography-mass spectrometry (HPLC-MS) were used to detect and analyze the distribution of 10 antibiotics including sulfonamides, fluoroquinolones, and macrolides in the Harbin section of Songhua River basin and Ashe River, a tributary of Songhua River. The correlation between the antibiotic concentration and water quality indexes was analyzed and the ecological risks were evaluated. The results showed that only six antibiotics were detected in the entry section of Harbin city on the Songhua River and the concentration was relatively low. However, nine antibiotics were detected in the exit section and only sulfamethazine (SM1) was not detected. The concentrations of macrolide antibiotics increased most significantly, followed by those of sulfonamides and fluoroquinolones. The inflow of three tributaries in Harbin city was the direct cause of the increase in antibiotic concentration in the Songhua River. Only sulfapyridine (SMPD) was not detected in the upper section of Ashe River. Ten antibiotics were detected in the section where the Ashe River enters the Songhua River. The other nine antibiotics were the highest except norfloxacin (NOR). Wastewater discharged from four sewage treatment plants along Ashe River is an important factor affecting the concentration of antibiotics in the Ashe River. Correlation analysis shows that three kinds of antibiotics in the Songhua River have certain positive correlations with ammonia nitrogen, total phosphorus, and total organic carbon. There is a significant positive correlation between the three kinds of antibiotics and ammonia nitrogen and total phosphorus in the Ashe River system, indicating that the water quality indexes of the Harbin section of Songhua River and Ashe River are closely related to their antibiotic concentrations. The results of ecological risk assessment showed that macrolide antibiotics in the Harbin section of Songhua and Ashe Rivers had certain ecological risks.

Confined animal feeding operations generate high concentrations of airborne antibiotic-resistant bacteria, including pathogenic strains that may pose a health risk to both animals and farm workers and pollute the local air environment. In this study, tetracycline and erythromycin-resistant bacteria were used as examples to study the biodiversity and community structure of airborne antibiotic-resistant bacteria in animal farms. The Anderson sampler was used to collect bioaerosols samples from the inside environment and outside atmospheric environments. A comparative analysis of biological differences of antibiotic-resistant bacteria was conducted on fine and coarse particles, bioaerosol samples inside the house, fecal samples, and inside and outside bioaerosol samples based on the result of the Illumina MiSeq sequencing. The key genus that drives the above differences was also studied. Results showed that the biodiversity of airborne erythromycin-resistant bacteria was higher than that of airborne tetracycline-resistant bacteria, and the biodiversity of bioaerosol samples in the house was higher than that in fecal samples. There were no significant differences in the biodiversity and community structure of airborne antibiotic-resistant bacteria between fine and coarse particles. Actinobacteria is one of the key bacteria responsible for the differences between erythromycin-resistant bacteria and other bacterial populations.

Three MBBRs and three curtain type trickling filters (CTFs) with different carriers were operated in lab-scale simulated RASs. The characteristics of biofilms, ammonia removal rates and microbial communities in six reactors were compared with each other. Compared with the biofilms of MBBRs, the biofilms of CTFs were heavier and grew faster. The weight of biofilms on CTFs with carbon fiber carriers was the maximum (45.97 g·m

Pseudomonas syringae pv. tabaci (Pst) is a hemibiotrophic bacterial pathogen responsible for tobacco wildfire disease. Although considerable research has been conducted on the tobacco plant’s tolerance to Pst, the role of light in the responses of the photosystems to Pst infection is poorly understood. This study aimed to elucidate the underlying mechanisms of the reduced photosystem damage in tobacco leaves due to Pst infection under light conditions. Compared to dark conditions, Pst infection under light conditions resulted in less chlorophyll degradation and a smaller decline in photosynthetic function. Although the maximal quantum yield of photosystem II (PSII) and the activity of the photosystem I (PSI) complex decreased as Pst infection progressed, damage to PSI and PSII after infection was reduced under light conditions compared to dark conditions. Pst was 17-fold more abundant in tobacco leaves under dark compared to light conditions at 3 days post-inoculation (dpi). Additionally, hydrogen peroxide (H2O2) accumulated to a high level in tobacco leaves after Pst infection under light conditions; although to a lesser extent, H2O2 accumulation was also significant under dark conditions. Pretreatment with H2O2 alleviated chlorotic lesions and decreased Pst abundance in tobacco leaves at 3 dpi under dark conditions. Methyl viologen (MV) pretreatment had the same effects under light conditions, whereas 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) pretreatment aggravated chlorotic lesions and increased the Pst population. These results indicate that chlorotic symptoms and the size of the bacterial population are each negatively correlated with H2O2 accumulation. In other words, light appears to suppress the Pst population in tobacco leaves through the accumulation of H2O2 during infection.

EDTA, EDDS and citric acid were added to moderate artificial contaminated soil to investigate the effects of the organic acids on growth of maize seedlings and phytoextraction of lead by maize. The results show that the effects of the organic acids on plant growth are different in Pb contaminated soil. The organic acids can change the dry matter distribution of the shoots and the roots and can increase the shoots biomass in most case. EDTA and EDDS can significantly increase the concentrations and uptake of Pb in the shoots of maize, indicate that EDDS is a potential phytoextraction intensifier in phytoremediation of Pb-contaminated soil.

In this paper, E. coli as experimental subjects ，by changing the input voltage, bacterial concentration, turbidity and pH to study the impact that the use intense white light on the inactivation of E. coli in medium surface. The results showed that: light pulses had a strong effect on lethal E. coli, with the input voltage increasing, the inactivation rate increased. The input voltage is 2500v as an appropriate experimental condition, that satisfy both conservation of energy and a better inactivation .The inactivation rate and the logarithm of livability of E. coli rising with the bacterial concentration increasing, when the light flashes six times, the medium surface almost be killed. Turbidity affect to the inactivation of E. coli, with the turbidity increasing, the effect of the inactivation gradually weakened. When ph was changed, the impact of pulsed light on E. coli inactivation was less .The effect of inactivation achieve the best level when pH was 6.

The effects of pulsed white light, input voltage, biological load, pH and turbidity on inactivation of Staphylococcus aureus in drinking water were studied. The results showed that the effect of pulsed white light on the inactivation of Staphylococcus aureus in drinking water was very significant. The concentration of S. aureus reduced to 1.0×101cfu/ml as the pulsed white light flashed for 8 times when the input voltage was 3000v. The inactivation increased with the plus of input voltage, and decreased with the added of biological load. The inactivation kept all most the same when pH is 5.0~9.0, and the effect of turbidity was not obvious when the turbidity was 5~25.

In this paper, One-step pyrolysis process for the recovery of mercury and zinc from spent zinc–manganese batteries is proposed. Laboratory tests were performed to remove mercury and zinc from spent batteries and recover them. Correctitude test were used to analyze the effect of three factors: temperature, weight and time on the removing and recovery efficiency of zinc. In this research, temperature is dominant factor, weight and time are subordinate. After removing mercury, higher temperature could assure the removing efficiency of mercury above 99.9% at the same time of removing zinc. Under 0.02 MPa, efficiency of removing and recycling of zinc were investigated. The removing efficiency is 94.2% at 950 °C and 96.2% at 1000 °C. When the heated time is 1.5 h, the removing efficiency is 95.6%, which reach the aim 95.0%. With the increase of sample weight, the necessary heated time could be kept within 2.5 h without the loss of removing efficiency. The recycling efficiency of zinc could approach 75%. The content of zinc is above 99.0% in condensed zinc product. After being treated, the residue mass is about 40% of sample.

In order to investigate low-temperature influence on the SBR process and sludge bulking, the SBR process pollutants removal effect was studied with normal and low temperature. The experimental results showed that the effluent water quality was better with temperature 22~24°C and DO 2mg/L. During this period, sludge bulking did not happen and the SVI was stable for 30d at the range of 60~80mL/g. The sludge settlement became worse when the temperature sharply dropped to 13~15°C and DO concentration was unchanged, the SVI was sharply increased to 240~270mL/g from 60~80mL/g in several cycles, and it was in the state of sludge bulking for 60d. The system denitrification effect was almost lost and the nitrification effect had been seriously affected. When the temperature returned to normal, the nitrification effect was gradually improved. The effluent water was clear and the SVI returned gradually, but the SVI eventually maintained at 150mL/g without retune to previous range.

Zeolite is a kind of normal adsorber. Unfortunately the adsorption capacity of natural zeolite is low, it must be activated on behalf of reaching a higher adsorption capacity. On this condition, removal of phosphorus through modifying zeolite has been studied in lab scale through using a mechanically stirred batch system. The results showed that the adsorption isotherm of modified zeolite conformed to Freundlich model and the rate of adsorption conformed to Banerm equation.

Chironomus kiiensis larvae which cannot be exterminated by conventional disinfection process propagates prolifically in eutrophic water body, and it therefore turns to be a potential problem encountered in drinking water quality. In this work, the quantitative experimental studies were carried out on removal of Chironomus kiiensis larvae in raw water by coagulation-sedimentation process. The coagulation jar test showed that the Chironomus kiiensis larvae could be partially removed from water by coagulation-sedimentation process. Based on it, removal effect of pre-oxidation combined with coagulation-sedimentation process on Chironomus kiiensis larvae was evaluated. The results showed that chlorine dioxide pre-oxidation possessed better removal performance than prechlorinion, and Chironomus kiiensis larvae in the raw water could be completely removed by chlorine dioxide pre-oxidation in combination with the coagulation-sedimentation process at chlorine dioxide dosage of 0.8mg/L. The pH in the range of 6-8 did not affect the inactivation efficiency of chlorine dioxide, whereas pH 10 resulted in around 10% decrease in removal rate. Meanwhile, the removal rate of Chironomus kiiensis larvae improved with the temperature increasing within the range investigated of 15-30°C. The removal rate was reduced by 6.7% when temperature reduced from 30°C to 15°C.

Comparing with the phytoplankton, there are few researches on zooplanktons. Now, many waterworks don’t monitor the zooplanktons in source water. There isn’t effective detection method for several common macro zooplanktons such as chironomid larvae, cyclops and so on, and little has been done in the field of the macro zooplanktons automatic identification and monitor. This paper puts for forward a macrozooplankton edge detection method based on wavelet packet decomposition and reconstruction. We erase the high frequency parts by applying wavelet packet decomposition in the original images and then detect the edge of reconstruction images using the common edge detectors such as Prewitt, Sobel, Roberts, Laplacian of Gaussion, Canny and so on. The experimental results show that the edge detection methods in the reconstruction image work better than in the original image.

In this paper, comparative experiments on the inactivation of Chironomid larvae by ozone and chlorine were conducted. In addition, batch experiments were performed in order to analyze the influence of pH value, organic precursor concentration and temperature on the inactivation efficiency of Chironomid larvae with ozone. Based on it, removal effect of different pre-oxidation combined with coagulation process on Chironomid larvae in raw water was evaluated. The results showed that ozone possessed better inactivation performance than chlorine, and complete inactivation of Chironomid larvae in raw water was obtained at ozone dose of 2.0 mg/L after 25 minutes of contact time. The inactivation rate of Chironomid larvae at pH 6.0 was higher than those found at pH 8.0 in same contact time. Meanwhile, the organic precursor had negative effects on inactivation, indicated by the decreasing inactivation rate from 100% at TOC concentration of 0 mg/L to 20.0% at 8 mg/L after 30 min of contact time. With regard to the temperature, the inactivation efficiency of Chironomid larvae improved with the temperature increasing within the range investigated of 10–25°C. The inactivation rate was reduced by 73.3% when temperature reduced from 25°C to10°C. The coagulation jar test showed that Chironomid larvae in the raw water could be completely removed by ozone pre-oxidation combined with the coagulation process at ozone dosage of 1.2 mg/L.

Data collection of soil organic carbon(SOC) of 154 soil series of Jiangsu, China from the second provincial soil survey and of recent changes in SOC from a number of field pilot experiments across the province were collected. Statistical analysis of SOC contents and soil properties related to organic carbon storage were performed. The provincial total topsoil SOC stock was estimated to be 0.1 Pg with an extended pool of 0.4 Pg taking soil depth of 1 m, being relatively small compared to its total land area of 101700 km2 . One quarter of this topsoil stock was found in the soils of the Taihu Lake region that occupied 1/6 of the provincial arable area. Paddy soils accounted for over 50% of this stock in terms of SOC distribution among the soil types in the province. Experimental data from experimental farms widely distributed in the province showed that SOC storage increased consistently over the last 20 years despite a previously reported decreasing tendency during the period between 1950--1970. The evidence indicated that agricultural management practices such as irrigation, straw return and rotation of upland crops with rice or wheat crops contributed significantly to the increase in SOC storage. The annual carbon sequestration rate in the soils was in the range of 0.3-3.5 tC/(hm2 x a), depending on cropping systems and other agricultural practices. Thus, the agricultural production in the province, despite the high input, could serve as one of the practical methods to mitigate the increasing air CO2.

Background Pseudomonas syringae pv. tabaci (Pst), which is the pathogen responsible for tobacco wildfire disease, has received considerable attention in recent years. The objective of this study was to clarify the responses of photosystem I (PSI) and photosystem II (PSII) to Pst infection in tobacco leaves. Results The net photosynthetic rate (Pn) and carboxylation efficiency (CE) were inhibited by Pst infection. The normalized relative variable fluorescence at the K step (Wk) and the relative variable fluorescence at the J step (VJ) increased while the maximal quantum yield of PSII (Fv/Fm) and the density of QA-reducing PSII reaction centers per cross section (RC/CSm) decreased, indicating that the reaction centers, and the donor and acceptor sides of PSII were all severely damaged after Pst infection. The PSI activity decreased as the infection progressed. Furthermore, we observed a considerable overall degradation of PsbO, D1, PsaA proteins and an over-accumulation of reactive oxygen species (ROS). Conclusions Photoinhibition and photoinhibition-like damage were observed under light and dark conditions, respectively, after Pst infection of tobacco leaves. The damage was greater in the dark. ROS over-accumulation was not the primary cause of the photoinhibition and photoinhibition-like damage. The PsbO, D1 and PsaA proteins appear to be the targets during Pst infection under light and dark conditions. Electronic supplementary material The online version of this article (doi:10.1186/s12870-016-0723-6) contains supplementary material, which is available to authorized users.

The traditional method of detecting Chironomid larvaes and plankton in water mostly is observation by Naked Eye, which is inefficient and inaccurate. This paper puts forward the Chironomid larvae image recognition method which is based on the support vector machines and multi-layered wavelet decomposition. Gradation histogram balance strengthening treatment is carried out for the image, so as to improve the contrast ratio and make for the threshold division. For each image, a 36 dimension feature vector is computed via two-level discrete Wavelet transform (DWT). The last step of the proposed approach consists is using support vector machine(SVM) as classifer and Wavelet energy as features to recognize the images. Extensive classification experiments on our image data validate that it is promising to employ the proposed texture features to recognize Chironomid larvaes in image.

The toxic effect of chlorine dioxide to the different instar larvae of chironomid was studied using raw water as test sample. Furthermore, the effect of temperature and contact time on toxicity of chlorine dioxide was observed. It was found that chlorine dioxide possessed significantly toxic effect, and the LC50 value of chlorine dioxide to the 4th instar larvae was 0.41 mg/L(24 h). The toxicity of chlorine dioxide declined with the development of instar larvae. The 1st instar larvae was most sensitive to chlorine dioxide among the four instars, and the LC50 value of chlorine dioxide to the 4th instar was 1.78 times of that of the 1st instar larvae. Temperature was proved to have significant positive effect on chlorine dioxide toxicity, and the toxicity at 30 degrees C was 2.16 times of that at 15 degrees C. The toxicity of chlorine dioxide was significantly improved with the contact time increasing from 12 h to 24 h, while it did not make much difference with the contact time increasing to 36 h.

In this paper, comparative experiments on the inactivation of Chironomid larvae by chlorine dioxide and chlorine were conducted. In addition, batch experiments were performed in order to analyze the influence of pH value, organic precursor concentration and temperature on the inactivation efficiency of Chironomid larvae with chlorine dioxide. Based on it, removal effect of different pre-oxidation followed by coagulation process on Chironomid larvae in raw water was evaluated. The results showed that chlorine dioxide possessed better inactivation performance than chlorine, and complete inactivation of Chironomid larvae was obtained at CT value of 37.5 mg min/L (dose of 1.5mg/L and exposure time of 25 min). The pH in the range of 6-8 did not affect the inactivation efficiency of chlorine dioxide, whereas pH 10 resulted in around 10% decrease in inactivation rate. Meanwhile, the organic precursor had negative effects on inactivation, indicated by the decreased inactivation rate from 100% at TOC concentration of 0mg/L to 62.2% at 8 mg/L when the CT value was 45 mg min/L. With regard to the temperature, the inactivation efficiency of Chironomid larvae was significantly improved with the temperature increasing within the range investigated of 10-25 degrees C. The inactivation rate was reduced by 68.9% when temperature reduced from 25 degrees C to 10 degrees C. The coagulation jar test showed that Chironomid larvae in the raw water could be completely removed by chlorine dioxide pre-oxidation in combination with the coagulation process at CT value of 24.8 mg min/L.

The excessive propagation of Chironomid larvae (red worm) in the sedimentation tanks is a difficult problem for the normal function of waterworks. The toxic effect of liquid chlorine on the different instar larvae of Chironomid was studied using distilled water as test sample. Furthermore, the effect of pH value, organic matter content, ammonia nitrogen, and algae content on toxicity of liquid chlorine was observed. The results show that the tolerance of Chironomid larvae to liquid chlorine is strengthened with the increase in instar. The 24h semi-lethal concentration (LC50) of liquid chlorine to the 4th instar larvae of Chironomid is 3.39 mg/L. Low pH value and high algae content are helpful to improve the toxic effect of liquid chlorine to Chironomid larvae. In neutral water body, the increase in organic matter content results in the decrease in the death rate of Chironomid larvae. The toxicity of liquid chlorine differs greatly in different concentrations of ammonia nitrogen. The death rate of the 4th instar larvae of Chironomid in raw water is higher by contrast with that in sedimentation tanks water for 24h disposal with various amount of liquid chlorine.

Data collection of soil organic carbon(SOC) of 154 soil series of Jiangsu, China from the second provincial soil survey and of recent changes in SOC from a number of field pilot experiments across the province were collected. Statistical analysis of SOC contents and soil properties related to organic carbon storage were performed. The provincial total topsoil SOC stock was estimated to be 0.1 Pg with an extended pool of 0.4 Pg taking soil depth of 1 m, being relatively small compared to its total land area of 101700 km2 . One quarter of this topsoil stock was found in the soils of the Taihu Lake region that occupied 1/6 of the provincial arable area. Paddy soils accounted for over 50% of this stock in terms of SOC distribution among the soil types in the province. Experimental data from experimental farms widely distributed in the province showed that SOC storage increased consistently over the last 20 years despite a previously reported decreasing tendency during the period between 1950--1970. The evidence indicated that agricultural management practices such as irrigation, straw return and rotation of upland crops with rice or wheat crops contributed significantly to the increase in SOC storage. The annual carbon sequestration rate in the soils was in the range of 0.3-3.5 tC/(hm2 x a), depending on cropping systems and other agricultural practices. Thus, the agricultural production in the province, despite the high input, could serve as one of the practical methods to mitigate the increasing air CO2.

Background Elucidating the genetic basis underlying hepatic gene expression variability is of importance to understand the aetiology of the disease and variation in drug metabolism. To date, no genome-wide expression quantitative trait loci (eQTLs) analysis has been conducted in the Han Chinese population, the largest ethnic group in the world. Methods We performed a genome-wide eQTL mapping in a set of Han Chinese liver tissue samples (n=64). The data were then compared with published eQTL data from a Caucasian population. We then performed correlations between these eQTLs with important pharmacogenes, and genome-wide association study (GWAS) identified single nucleotide polymorphisms (SNPs), in particular those identified in the Asian population. Results Our analyses identified 1669 significant eQTLs (false discovery rate (FDR)