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Frontiers of Environmental Science & Engineering 2015年第1期9卷 50-57页

作者： Pengfei LIN Xiaojian ZHANG Hongwei YANG Yong LI School of Environment Tsinghua University Beijing 100084 China Changping water Authority of Beijing Beijing 102200 China

Arsenic （As） spills and sometimes polluted water occurred more frequently sources in recent years in China. It is as urgent need to develop emergency treatment technologies to address the arsenic threat for large-scale water treatment plants. In response, we developed a chemical sedimentation technology to remove arsenic contaminants for water treatment plants. Bench-scale experiments were conducted to investigate the efficiency of arsenic removal and the influencing factors of the chemical sedimentation treatment process. The influencing factors included the choice and dosage of coagulants, the valence of arsenic and pH value of solution. The As（V） contaminants can be almost completely removed by ferric or alum coagulants. The As（III） contaminants are more recalcitrant to chemical sedimentation, 75% for ferric coagulant and 40% for alum coagulant. The quantitative results of arsenic removal load by different ferric or alum coagulants were presented to help determine the parameters for arsenic treatment technology. The dominant mechanism for arsenic removal is static combination, or adsorption of negative arsenic species onto positive ferric hydroxide or alum hydroxide flocs. The efficiency of this treatment technology has also been demonstrated by a real production test in one water treatment plant with arsenicrich source water and one emergency response. This technology was verified to be quick to set-up, easy to operate and highly efficient even for high concentration of arsenic.

关键词： Arsenic spill chemical sedimentation coagulation drinking water emergency treatment

Impacts of advanced treatment processes on elimination of antibiotic resistance genes in a municipal waste water treatment plant

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Frontiers of Environmental Science & Engineering 2019年第3期13卷 69-78页

作者： Lian Yang Qinxue Wen Zhiqiang Chen Ran Duan Pan Yang State Key Laboratory of Urban water Resource and Environment Harbin Institute of Technology (SKLUWRE HIT) Harbin 150090 China National & Local Joint Engineering Laboratory for Municipal Sewage Resource Utilization Technology Suzhou University of Science and Technology Suzhou 215009 China

Antibiotic resistance genes (ARGs) pose a serious threat to public health. Wastewater treatment plants (WWTPs) are essential for controlling the release of ARGs into the environment. This study investigated ARG distribution at every step in the treatment process of a municipal WWTP located in Harbin for six consecutive months. Changes in ARG distribution involved in two advanced secondary effluent treatment processes, ozonation and granular activated carbon (GAC) adsorption, were analyzed. Biological treatment resulted in the highest ARG removal (0.76-1.94 log reduction), followed by ultraviolet (UV) disinfection (less than 0.5-log reduction). Primary treatment could not significantly remove ARGs. ARG removal efficiency increased with an increase in the ozone dose below 40 mg/L. However, amorphous GAC (AGAC) adsorption with a hydraulic retention time (HRT) of 1 h showed better removal of ARGs, total organic carbon (TOC), total nitrogen (TN), and total phosphorus (TP) than ozonation at a 60 mg/L dose. UV treatment could efficiently reduce the relative ARG abundance, despite presenting the lowest efficiency for the reduction of absolute ARG abundance compared with GAC and ozone treatments. The combination of ozone and AGAC can significantly improve the removal of ARGs, TOC, TN and TP. These results indicate that a treatment including biological processing, ozonation, and AGAC adsorption is a promising strategy for removing ARGs and refractory organic substances from sewage.

关键词： Antibiotic resistance genes (ARGs) Wastewater treatment plant (WWTP) Ultraviolet (UV) Ozonation Granular activated carbon (GAC)

Migration of Heavy Metal Elements in Reclaimed Irrigation water-Soil-plant System and Potential Risk to Human Health

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Asian Agricultural Research 2021年第10期13卷 41-47,53页

作者： Zixi LIU Juncang TIAN Wangcheng LI Lian TANG Jie WANG Haiyan GAO School of Civil Engineering and Hydraulic Engineering Ningxia UniversityYinchuan 750021China Engineering Technique Research Center for water Saving Irrigation and water Resources Yinchuan 750021China Engineering Research Center of the Ministry of Education for the Modern Utilization of Modern Agricultural water Resources in Arid Areas Yinchuan 750021China

[Objectives]To study the impact of heavy metal pollution of soil and plants during the process of reclaimed water for irrigation of green land in arid areas and the potential health risks to humans during use.[Methods]Taking Zhongwei City in Ningxia,a typical arid area,as the research area,the irrigation water,soil and green grass in the reclaimed water irrigation region and the original green water irrigation region were sampled,the heavy elements Hg,As,Zn,Pb,Cd,Cr were detected,and the Nemerow method,biological absorption coefficient,and health risk assessment were employed to evaluate the degree of soil pollution,plant absorption capacity,and human health risks.[Results]Compared with the original green water,the Hg,Cd,and Cr pollution of the reclaimed water irrigated green land was higher,the As,Zn,Pb pollution was lower,and the content of Hg and Cd was higher than the environmental background values of soil in Ningxia;the Cr content exceeded the risk intervention values of the first type of land in the Soil Environmental Quality—Risk Control Standard for Soil Contamination of Development Land(GB 36600-2018).Compared with the original green water irrigation region,it is found that the reclaimed water irrigation reduced the heavy metal pollution of the soil to a certain *** heavy metal content of tall fescue grass(Festuca arundinacea)in the reclaimed water irrigation region was Zn,Cr,Pb,As,Cd,and Hg from high to low;the order of the biological absorption coefficient was Cd>As>Zn>Pb>Hg>Cr;irrigation water exerted a certain effect on the content of heavy metals in plants and the biological absorption coefficient through the *** the health risk assessment method recommended by Environmental Protection Agency of the United States of America(USEPA),it was found that the reclaimed water has the highest risk through the inhalation route,and the occupational population has a higher risk of skin contact with soil and plants.[Conclusions]This study is intended

关键词： Reclaimed water irrigation water-soil-plant system Migration of heavy metal elements Health risk assessment

Characterization of bacterial community dynamics in a full-scale drinking water treatment plant

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Journal of Environmental Sciences 2017年第1期29卷 21-30页

作者： Cuiping Li Fangqiong Ling Minglu Zhang Wen-Tso Liu Yuxian Li Wenjun Liu School of Environment Tsinghua UniversityBeijing 100084China. Department of Civil and Environment Engineering University of Illinois at Urbana-ChampaignUrbanaIL 62801USA School of Food and Chemical Engineering Beijing Technology and Business UniversityBeijing 100048China water Quality Monitoring Center Beijing Waterworks GroupBeijing 100085China

Understanding the spatial and temporal dynamics of microbial communities in drinking water systems is vital to securing the microbial safety of drinking *** objective of this study was to comprehensively characterize the dynamics of microbial biomass and bacterial communities at each step of a full-scale drinking water treatment plant in Beijing,*** bulk water and biofilm samples on granular activated carbon（GAC） were collected over 9 *** proportion of cultivable cells decreased during the treatment processes,and this proportion was higher in warm season than cool season,suggesting that treatment processes and water temperature probably had considerable impact on the R2 A cultivability of total bacteria.16 s rRNA gene based 454 pyrosequencing analysis of the bacterial community revealed that Proteobacteria predominated in all *** GAC biofilm harbored a distinct population with a much higher relative abundance of Acidobactena than water *** coordinate analysis and one-way analysis of similarity indicated that the dynamics of the microbial communities in bulk water and biofilm samples were better explained by the treatment processes rather than by sampling time,and distinctive changes of the microbial communities in water occurred after GAC ***,20 distinct OTUs contributing most to the dissimilarity among samples of different sampling locations and 6 persistent OTUs present in the entire treatment process flow were ***,our findings demonstrate the significant effects that treatment processes have on the microbial biomass and community fluctuation and provide implications for further targeted investigation on particular bacteria populations.

关键词： Heterotrophic plate count Flow cytometry 454 pyrosequencing Bacterial community Dynamics

Sensitivity analysis of the SWAP(Soil-water-Atmosphere-plant)model under different nitrogen applications and root distributions in saline soils

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Pedosphere 2021年第5期31卷 807-821页

作者： Guoqing LEI Wenzhi ZENG Yonghua JIANG Chang AO Jingwei WU Jiesheng HUANG State Key Laboratory of water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072(China) School of Remote Sensing and Information Engineering Wuhan UniversityWuhan 430079(China) State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430079(China)

Sensitivity analysis is important for determining the parameters in the model calibration *** our study,a variance-based global sensitivity analysis(extended Fourier amplitude sensitivity test,EFAST)was applied to an agro-hydrological model(the SWAP(Soil-water-Atmosphere-plant model)model).The sensitivities of 20 parameters belonging to 4 categories(soil hydraulics,solute transport,root water uptake,and environmental stresses)for the simulated accumulated transpiration,dry matter(DM),and yield of sunflowers were analyzed under three nitrogen application rates(N1,N2,and N3),four salinity levels(S1,S2,S3,and S4),and three root distributions(R1,R2,and R3).The results indicated that for predominantly loamy soils,the high-impact parameters for accumulated transpiration,DM,and yield were the soil hydraulic parameters(αand n),critical stress index for compensatory root water uptake(ωc),the salt level at which salt stress starts(Pi),the decline of root water uptake above Pi(SSF),residual water content(θr),saturated water content(θs),and relative uptake of solutes by roots(TSCF).We also found that nitrogen application did not change the order of the parameter impacts on accumulated transpiration,DM,and ***,TSCF replacedαas the highest-impact parameter for the accumulated transpiration,DM,and yield at high salinity levels(S2 and S3).Furthermore,αwas also the highest-impact parameter for DM and yield under different root distributions,but the highest-impact parameters for transpiration wereωc,α,andθs under R1,R2,and R3,*** application could be neglected when considering the interactive effects of nitrogen application,salinity level,and root distribution on the transpiration,DM,and ***,the mean values and uncertainties of the transpiration,DM,and yield were similar in all scenarios,except S3,which showed a sharp decrease in the mean *** suggest determining the above eight parameters(α,n,ωc,Pi,SSF,θr,θs,and TSCF)and the sat

关键词： accumulated transpiration agro-hydrological model dry matter hydraulic parameter sunflower yield

Physico-Chemical Characterization of Sludge from the Goudel Drinking water Production plant in Niamey (Niger)

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Natural Resources 2022年第10期13卷 206-216页

作者： Ibrahim Soumaïla Siddo Mahaman Moustapha Adamou Fayçal Moumouni Abou Rural Engineering Water Resources and Forestry Department Faculty of Agronomy Abdou Moumouni University Niamey Niger

Population growth and increasing needs make our current societies a considerable source of environmental threats. Going towards sustainable cities where harmony exists between economic, socio-cultural and environmental issues is a necessity that is essential if we want to bequeath a livable world to future generations. Cities produce huge quantities of domestic and industrial waste, the management of which is becoming a growing problem for city managers. Located on the banks of the Niger River, the city of Niamey, capital of the Republic of Niger, is supplied with drinking water from this river. Significant quantities of sludge are produced by the plant following the treatment of this water. This study focuses on the physico-chemical characterization of this sludge which is now directly discharged into the Niger River. A total of 12 samples of pasty sludge taken from the pre-settling ponds were analyzed. The samples were previously dried, crushed, sieved and packaged. Physical (pH, EC and particle size), chemical (Ca, Mg, Na, K, CEC, AE, P, C, MO and N) and metallic trace elements (Pb, Ni, Cu, Zn, Cd, Mn) parameters and Al) were analyzed in the laboratory. The results show that the sludge is weakly acidic (pH between 4.16 and 5.71), conductive (<0.35 mS/cm) and rich in fine elements (12.1% to 77.71% clay). The nutrient content is low in nitrogen (<0.25%), phosphorus (<2.5 ppm), potassium (between 1 to 188 Mèq/100g) and organic matter (less than 2.88%). The concentrations of ETM comply with the values admissible in residual materials (French decree of 08/01/1998). This sludge can be recovered, especially in agriculture.

关键词： Sludge Potable water water Treatment Niger River Niamey

Risk Assessment from Catchment to Consumers as Framed in water Safety Plans: A Study from Maiduguri water Treatment plant, North East Nigeria

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Journal of Environmental Protection 2019年第10期10卷 1373-1390页

作者： Mohammed Mustapha M. K. C. Sridhar A. O. Coker Ayotunde Ajayi Abubakar Suleiman Department of Agricultural and Environmental Resources Engineering Faculty of Engineering University of Maiduguri Maiduguri Nigeria Departmentof Environmental Health Sciences Faculty of Public Health University of Ibadan Ibadan Nigeria Department of Civil Engineering Faculty of Technology University of Ibadan Ibadan Nigeria Kelamide-O Nigeria Ltd Aderibigbe St. Off Halleluya Estate Osogbo Osun State Nigeria Maiduguri water Treatment plant Operations Department Maiduguri Nigeria.

water safety plan as conceived by WHO can lead to prevention of pollution in each component of water supply chain which leads to ensuring safe drinking water. Risk assessment is one of the key components during the development of water safety plan, achieved by identifying hazardous events and estimating their risk towards implementing control measures. This study reports the risk assessment from catchment to consumers in Maiduguri water treatment plant in Northeast Nigeria. Tools such as the field visits, key informant interviews, questionnaire and water quality monitoring were used to identify the hazards and estimate their risk using semi-quantitative matrix. With the existing control measures, the study showed a total of 33 hazardous events;5 in catchment, 16 in treatment plant, 6 in distribution system and 6 at consumers’ points. The risk score indicated 6 are of medium risk and 9 of high risk. Catchment activities, upgrade of treatment facilities and lack of routine maintenance in the treatment plant, pipeline damages in distribution lines, and consumers’ lack of hygiene knowledge and awareness were found to be the major contributory factors which affect the desired quality. Therefore participation and commitment by all relevant stakeholders are fundamental requisite to manage the identified health risks.

关键词： water Safety Plan Hazard Identification Risk Assessment Maiduguri water Treatment

In-situ nitrogen removal from the eutrophic water by microbial-plant integrated system

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第7期7卷 521-531页

作者： CHANG Hui-qing YANG Xiao-e FANG Yun-ying PU Pei-min LI Zheng-kui RENGEL Zed Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health School of Natural Resources and Environmental Science Zhejiang University Hangzhou 310029 China Department of Geography and Environment Nanjing University Nanjing 210008 China Soil Science and plant Nutrition School of Earth and Geographical Sciences University of Western Australia Crawley WA 6009 Australia

Objective: This study was to assess the influence of interaction of combination of immobilized nitrogen cycling bacteria (INCB) with aquatic macrophytes on nitrogen removal from the eutrophic waterbody, and to get insight into different mechanisms involved in nitrogen removal. Methods: The aquatic macrophytes used include Eichhornia crassipes (sum-mer-autumn floating macrophyte), Elodea nuttallii (winter-growing submerged macrophyte), and nitrogen cycling bacteria in-cluding ammonifying, nitrosating, nitrifying and denitrifying bacteria isolated from Taihu Lake. The immobilization carriers materials were made from hydrophilic monomers 2-hydroxyethyl acrylate (HEA) and hydrophobic 2-hydroxyethyl methylacrylate (HEMA). Two experiments were conducted to evaluate the roles of macrophytes combined with INCB on nitrogen removal from eutrophic water during different seasons. Results: Eichhornia crassipes and Elodea nuttallii had different potentials in purification of eutrophic water. Floating macrophyte+bacteria (INCB) performed best in improving water quality (during the first experiment) and decreased total nitrogen (TN) by 70.2%, nitrite and ammonium by 92.2% and 50.9%, respectively, during the experimental period, when water transparency increased from 0.5 m to 1.8 m. When INCB was inoculated into the floating macrophyte system, the populations of nitrosating, nitrifying, and denitrifying bacteria increased by 1 to 2 orders of magnitude compared to the un-inoculated treatments, but ammonifying bacteria showed no obvious difference between different treatments. Lower values of chlorophyll a, CODMn, and pH were found in the microbial-plant integrated system, as compared to the control. Highest reduction in N was noted during the treatment with submerged macrophyte+INCB, being 26.1% for TN, 85.2% for nitrite, and 85.2% for ammonium at the end of 2nd experiment. And in the treatment, the populations of ammonifying, nitrosating, nitrifying, and de-nitrifying bacteria incre

关键词： Nitrogen Immobilized nitrogen-cycling bacteria (INCB) Eutrophication Eichhornia crassipes Elodea nuttallii

OsPHR2-mediated recruitment of Pseudomonadaceae enhances rice phosphorus uptake

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plant Communications 2024年第8期5卷 137-146页

作者： Jianping Liu Weifeng Xu Qian Zhang Wencheng Liao Liang Li Shu Chen Jinyong Yang Zhengrui Wang Feiyun Xu Center for plant water-use and Nutrition Regulation and College of JunCao Science and Ecology Joint International Research Laboratory of Water and Nutrient in CropFujian Agriculture and Forestry UniversityFuzhou 350002China

plants can shape their root microbiome to promote growth and nutrient *** STARVATION RESPONSE 2(OsPHR2)is a central regulator of phosphate signaling in rice,but whether OsPHR2 can shape the root microbiome to promote phosphorus uptake is ***,we investigate the role of OsPHR2 in recruiting microbiota for phosphorus uptake using high-throughput sequencing and metabolite ***2-overexpressing(OsPHR2 OE)rice showed 69.8%greater shoot P uptake in natural soil compared with sterilized soil under high-phosphorus(HP)conditions,but there was only a 54.8%increase in the wildtype(WT).The abundance of the family Pseudomonadaceae was significantly enriched in OsPHR2 OE roots relative to those of WT *** with the WT,OsPHR2 OE rice had a relatively higher abundance of succinic acid and methylmalonic acid,which could stimulate the growth of Pseudomonas sp.(P6).After inoculation with P6,phosphorus uptake in WT and OsPHR2 OE rice was higher than that in uninoculated rice under low-phosphorus(LP)*** together,our results suggest that OsPHR2 can increase phosphorus use in rice through root exudate-mediated recruitment of *** finding reveals a cooperative contribution of the OsPHR2-modulated root microbiome,which is important for improving phosphorus use in agriculture.

关键词： OsPHR2 rice organic acid phosphorus Pseudomonadaceae

plant grafting:Molecular mechanisms and applications

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Molecular plant 2024年第1期17卷 75-91页

作者： Ming Feng Frauke Augstein Abdul Kareem Charles W.Melnyk Department of plant Biology Linnean Center for Plant BiologySwedish University of Agricultural SciencesAlmas allé575651 UppsalaSweden

People have grafted plants since antiquity for propagation,to increase yields,and to improve stress *** cutting and joining of tissues activates an incredible regenerative ability as different plants fuse and grow as *** over a hundred years,people have studied the scientific basis for how plants ***,new techniques and a deepening knowledge of the molecular basis for graft formation have allowed a range of previously ungraftable combinations to ***,we review recent developments in our understanding of graft formation,including the attachment and vascular formation *** analyze why plants graft and how biotic and abiotic factors influence successful *** also discuss the ability and inability of plants to graft,and how grafting has transformed both horticulture and fundamental plant *** our knowledge about plant grafting improves,new combinations and techniques will emerge to allow an expanded use of grafting for horticultural applications and to address fundamental research questions.

关键词： plant grafting regeneration mobile molecules tissue adhesion vascular differentiation stress tolerance