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Arsenic fractionation and contamination assessment in sediments of thirteen lakes from the East Plain and Yungui Plateau Ecoregions, China

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Journal of Environmental Sciences 2014年第10期26卷 1977-1984页

作者： Fengyu Zan Shouliang Huo jingtian zhang Li zhang Beidou Xi Lieyu zhang State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Science College of Environmental Science and Engineering Anhui Normal University

Arsenic（As） fractions in the sediments of seven lakes from East Plain Ecoregion and six lakes from Yungui Plateau Ecoregion, China, were investigated. Results indicated that the total As concentrations in sediment samples of lakes of the East Plain Lake Ecoregion are higher than those of Yungui Plateau Lake Ecoregion. Residual As is the main fraction in sediment samples of lakes from both ecoregions, followed by reducible As and soluble or oxidizable As. The total As is correlated to oxidizable As and residual As in sediment samples from both lake ecoregions. As distribution in sediment samples of lakes of the East Plain Ecoregion appears to be affected by human activity, while the As origin mainly comes from natural sources in sediment samples of lakes in the Yungui Plateau Ecoregion. The potential ecological risk index and geoaccumulation index values suggest ＂low to moderate＂ risk degree and ＂unpolluted to moderately polluted＂ for As in the studied lake sediments.

关键词： Arsenic fractionation Sediment Contamination assessment Lake ecoregion

Comparison of different grafting methods on the effect of‘Candidatus Liberibacter asiaticus'transmission

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Fruit Research 2022年第1期2卷 140-146页

作者： Xiaoqing Cui jingtian zhang Yangyang Liu Xiaoling Luo Xiaoling Deng Sumiao zhang Meirong Xu Guangdong Province Key Laboratory of Microbial Signals and Disease Control Citrus Huanglongbing Research LaboratorySouth China Agricultural UniversityGuangzhou 510642China Plant Protection Station of Deqing County in Guangdong Deqing 526600China

Grafting is a commonly used method for citrus propagation and transmitting'Candidatus Liberibacter asiaticus'(CLas),the putative causing agent of citrus Huanglongbing(HLB).Optimization of the grafting inoculation methods facilitates the material preparation in HLB research.Citrus buds with CLas were grafted onto healthy sour tangerine(Citrus sunki Hort.ex Tanaka)seedlings by different methods such as top grafting(‘T'grafting and‘V'grafting)and side grafting(abdominal grafting).Along with the symptom observation,titers of CLas in the leaves were detected by RTqPCR monthly.The correlation between the growth status of buds or different grafting methods and the success rate of HLB transmission were analyzed.Our results suggest that sufficient DNA could be extracted to accurately detect the CLas from even only 0.0125 g leaf midrib or branch bark.The probability of CLas transmission was higher in plants inoculated with buds in better growth conditions.The success rate of‘T'grafting was significantly higher than that of side grafting and‘V'grafting.Additionally,in terms of HLB transmission efficiency,the two-bud grafting scheme was superior to the single-bud and three-bud grafting schemes.In conclusion,the grafting combinations with the highest HLB transmission efficiency were screened to provide a methodological reference for the practice or research of grafting to obtain plant material.

关键词： material conditions. grafting

Source apportionment of perfluoroalkyl substances in surface sediments from lakes in Jiangsu Province,China:Comparison of three receptor models

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Journal of Environmental Sciences 2017年第7期29卷 321-328页

作者： Yanjie Qi Zhuoshi He Shouliang Huo jingtian zhang Beidou Xi Shibin Hu State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Science College of Natural Resources and Environment Northwest A&F University

Receptor models have been proved as useful tools to identify source categories and quantitatively calculate the contributions of extracted sources.In this study,sixty surface sediment samples were collected from fourteen lakes in Jiangsu Province,China.The total concentrations of C_4–C_（14）-perfluoroalkyl carboxylic acids and perfluorooctane sulfonic acid（∑_（12）PFASs） in sediments ranged from 0.264 to 4.44 ng/g dw（dry weight）,with an average of 1.76 ng/g dw.Three commonly-applied receptor models,namely principal component analysis-multiple linear regression（PCA-MLR）,positive matrix factorization（PMF） and Unmix models,were employed to apportion PFAS sources in sediments.Overall,these three models all could well track the ∑_（12） PFASs concentrations as well as the concentrations explained in sediments.These three models identified consistently four PFAS sources：the textile treatment sources,the fluoropolymer processing aid/fluororesin coating sources,the textile treatment/metal plating sources and the precious metal sources,contributing 28.1%,37.0%,29.7% and 5.3% by PCA-MLR model,30.60%,39.3%,22.4% and 7.7% by PMF model,and 20.6%,52.4%,20.2% and 6.8% by Unmix model to the ∑_（12） PFASs,respectively.Comparative statistics of multiple analytical methods could minimize individual-method weaknesses and provide convergent results to enhance the persuasiveness of the conclusions.The findings could give us a better knowledge of PFAS sources in aquatic environments.

关键词： Perfluoroalkyl substance Source apportionment PCA-MLR PMF Unmix

Algal uptake of dissolved organic nitrogen in wastewater treatment plants

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Journal of Environmental Sciences 2016年第12期28卷 56-64页

作者： jingtian zhang Mingzhou Su Beidou Xi Guangren Qian Jianyong Liu Fei Hua Shouliang Huo State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Science School of Environmental and Chemical Engineering Shanghai University

The algal uptake of dissolved organic nitrogen （DON） in the anaerobic-anoxic-oxic （A20） process was investigated in this study. Anaerobic, aerobic and effluent DON samples from two wastewater treatment plants （WWTPs） were separated into hydrophilic and hydrophobic fractions using a DAX-8 resin coupled with an anion exchange resin and a nanofiltration （NF） pretreatment Hydrophilic DON accounted for 66.66%-88.74% of the entire DON for the two plants evaluated. After a 1S-day incubation, 16.95%-91.75% DON was bioavailable for algal growth, and untreated samples exhibited higher DON bioavailability, with 52.83% DON average uptake rates, compared with the hydrophilic and hydrophobic fractions （45.53% and 44.40%, respectively） because the pretreatment caused the inorganic salt to be resistant to algae. Anaerobic untreated samples, hydrophilic fractions and hydrophobic fractions showed higher DON reduction rates and higher biomass accumulation compared with the other DON fractions due to the decomposition of resistant organics by anaerobic and anoxic bacteria. DON in aerobic and effluent samples of plant A was more bioavailable than that of plant B with usages of 27.49%-55.26% DON. DON bioavailability in the anaerobic-anoxic-oxic process decreased in the following order： anaerobic 〉 effluent 〉 aerobic. The DON contents were reduced after anaerobic treatment in the two plants. The EEM-PARAFAC model identified three DON components, including two humic acid-like substances and one protein-like substance in plant A and two protein-like substances and one humic acid-like substance in plant B.

关键词： Dissolved organic nitrogen Algal uptake Wastewater

Apparent relationships between anthropogenic factors and climate change indicators and POPs deposition in a lacustrine system

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Journal of Environmental Sciences 2019年第9期31卷 174-182页

作者： Hanxiao zhang Shouliang Huo Kevin M. Yeager Chaocan Li Beidou Xi jingtian zhang Zhuoshi He Chunzi Ma State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Science Beijing 100012 China Department Earth and Environmental Sciences University of Kentucky Lexington KY 40506 USA

Climate change and anthropogenic activities are expected to impact the environmental behaviors and fates of persistent organic pollutants(POPs), however, quantitative studies on these combined factors are scarce. In this study, dichlorodiphenyltrichloroethane(DDTs), polycyclic aromatic hydrocarbons(PAHs), and polychlorinated biphenyls(PCBs)were used as examples to identify how and when those factors may be related to the deposition of POPs in the sediment of Lake Chaohu, China, using generalized additive models(GAMs). Three historical trends of DDT, PAH, and PCB deposition were delineated in a dated sediment core encompassing ~100 years of historical record: a steady state or gradually increasing stage, a rapidly increasing stage, and a declining stage. The GAM results showed that aquatic total phosphorus(TP) concentrations and regional GDP(anthropogenic factors) were dominant contributors to POP accumulation rates in the lake sediment. The fitted relationships between air temperature and sedimentary DDT and PAH concentrations were linear and negative, while a positive linear relationship was found for PCBs, suggesting that Lake Chaohu may have become a net source for DDTs and PAHs, and a sink for PCBs, under a progressively warming climate.

关键词： POPs Lake sediment Generalized additive models Climate change

Mobility and sulfidization of heavy metals in sediments of a shallow eutrophic lake, Lake Taihu, China

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Journal of Environmental Sciences 2015年第5期27卷 1-11页

作者： Shouliang Huo jingtian zhang Kevin M.Yeager Beidou Xi Yanwen Qin Zhuoshi He Fengchang Wu State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Science Department Earth and Environmental Sciences University of Kentucky

The technique of DGT（diffusive gradients in thin films） using three diffusive gel thicknesses was applied to estimate the mobility and bioavailability of heavy metals in sediments and porewater of Lake Taihu, China. The DGT results showed significantly positive correlations between Co, Pb, Cd and Mn, and Ni and Fe concentrations in porewater. Cu and Zn showed a significantly negative correlation with Mn, due to Cu combination with carbonates and Zn derived from agricultural pollution, respectively. The rank order of average concentrations of Co, Ni and Cd at each station was DGT1.92〉DGT0.78〉 DGT0.39, suggesting stronger resupply from sediments to porewater when using thicker diffusive gels. Comparing centrifugation and DGT measurements, Co, Ni and Cd are highly labile; Mn and Fe are moderately labile; and Cu, Zn and Pb are slightly labile. The variations of AVS concentrations in sediment cores indicate that metal sulfides in deeper layers are easily diffused into surface sediments.

关键词： Sulfidization process Heavy metals DGT（diffusive gradients in thin films）

Microbial bioavailability of dissolved organic nitrogen(DON) in the sediments of Lake Shankou,Northeastern China

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Journal of Environmental Sciences 2016年第4期28卷 79-88页

作者： Mingzhou Su jingtian zhang Shouliang Huo Beidou Xi Fei Hua Fengyu Zan Guangren Qian Jianyong Liu School of Environmental and Chemical Engineering Shanghai University State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences College of Environmental Science and Engineering Anhui Normal University

Dissolved organic nitrogen（DON）extracted from Lake Shankou sediments using KCl was isolated into hydrophobic and hydrophilic fractions.The bioavailabilities of the hydrophobic and hydrophilic fractions to three types of bacterial communities collected from sediments,activated sludge and compost products were examined.The DON recoveries obtained by DAX-8 and cation exchange resins treatment were 96.17% ± 1.58% and 98.14% ±0% for the samples obtained from N4 and N14 stations,respectively.After 25 days of incubation at 25℃,most DON（59% to 96%）was degraded.Hydrophilic DON exhibited a higher reduction rate than hydrophobic DON during the growth phase.Untreated wastewater from Changshuihe town was the main degradable DON source to station N4,and 93% of hydrophilic DON and 80% of hydrophobic DON were degraded.Station N14 received a large amount of refractory DON from forest soils and exhibited DON degradation rates of 82% and 71% for the hydrophilic and hydrophobic fractions,respectively.Amino acid contents and fluorescence intensities were also analyzed.Approximately 27% to 74% of amino acids were taken up by day 5,and their concentration gradually increased in the following days due to the decomposition of dissolved proteins.Parallel factor analysis resulted in identification of tryptophan-like proteins,tyrosine-like proteins and FA-like substances.During the growth phase,40%–51% of the tryptophan-like proteins were taken up by bacteria,and the accumulation of tyrosine-like proteins was attributed to the release of biotic substances.The concentration of the FA-like substances decreased due to microbial decomposition.

关键词： Microbial bioavailability Dissolved organic nitrogen （DON） Sediment Amino acids PARAFAC

Characterization, treatment and releases of PBDEs and PAHs in a typical municipal sewage treatment plant situated beside an urban river, East China

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Journal of Environmental Sciences 2013年第7期25卷 1281-1290页

作者： Xiaowei Wang Beidou Xi Shouliang Huo Wenjun Sun Hongwei Pan jingtian zhang Yuqing Ren Hongliang Liu State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal University State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences Department of Chemical and Biochemical engineering Western University State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University

Characterization, treatment and releases of eight polybrominated diphenyl ethers （PBDEs） congeners and sixteen polycyclic aromatic hydrocarbons （PAHs） in wastewater were evaluated along the treatment processes of a typical secondary treatment municipal sewage treatment plant （STP）（in Hefei City） situated the beside Nanfei River, East China. The findings showed that the average concentrations of the total PBDEs in raw wastewater and treated effluent were 188.578 and 36.884 ng/L respectively. Brominated diphenyl ether （BDE） 209 congener, the predominant PBDE in the STP and Nanfei River, could be related to the discharge of car-industry-derived wastes. For PAHs, the average concentrations in raw wastewater and treated effluent were 5758.8 and 2240.4 ng/L respectively, with naphthalene, benzo[a]pyrene and indeno[1,2,3-c,d]pyrene being detected at the highest concentrations. PAHs mainly originate from the combustion of biomass/coal and petroleum. The STP reduced about 80% of the PBDEs and 61% of the PAHs, which were eliminated mainly by sedimentation processes. The removal rates of PBDEs/PAHs increased with the increase of their solid-water partitioning coefficients. Accordingly, the STP＇s effluent, containing some PBDE congeners （e.g., BDE 47, 99 and 209, etc.） and low-molecular-weight PAHs, could be an important contributor of these contaminants＇ input to Nanfei River. It resulted in a significant increase of PBDE/PAH concentrations and PAH toxicological risk in the river water downstream. About 4.040 kg/yr of PBDEs and 245.324 kg/yr of PAHs could be released into the Nanfei River. The current conventional wastewater treatment processes should be improved to remove the relatively low-molecular-weight PBDEs/PAHs more effectively.

关键词： polybrominated diphenyl ethers polycyclic aromatic hydrocarbons municipal sewage treatment plant urban river

A 60-year sedimentary record of natural and anthropogenic impacts on Lake Chenghai,China

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Journal of Environmental Sciences 2012年第4期24卷 602-609页

作者： Fengyu Zan Shouliang Huo Beidou Xi jingtian zhang Haiqing Liao Yue Wang Kevin M.Yeager School of Environment Beijing Normal UniversityBeijing 100875China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental ScienceBeijing 100012China College of Environmental Science and Engineering Anhui Normal UniversityWuhu 241000China Department of Marine Science University of Southern MississippiStennis Space CenterMS 39529USA

Recent sediments from Lake Chenghai, China, were investigated at high temporal resolution to trace both natural and anthropogenic effects on the lake using total organic carbon （TOC）, total nitrogen （TN）, total phosphorus （TP）, organic phosphorus （Po）, inorganic phosphorus （Pi） and organic carbon and nitrogen stable isotopes （~13Corg and 615N） in a 137Cs-dated sediment core. The results indicated that the sedimentary record covers the last 60 years, during which the lake had undergone apparent changes in nutrient sources and productivity in response to nutrient loading. Prior to the late 1980s, the nutrient contents in sediments mainly originated from algae and lake productivity was relatively stable. Since the late 1980s, increasing TOC, TN and TP concentrations together with the change of 613Corg and 615N suggested anthropogenic perturbations in nutrient loading and lake productivity. Endogenic nutrients derived from algae and anthropogenic inputs were two important sources of sedimentary nutrients. The anthropogenic nutrients mainly originated from the discharge of industrial wastewater and artificial cultivation of Spirulina after the middle 1980s, and domestic wastewater discharged from Yongsheng County since 1993.

关键词： stable isotope C/N ratio organic matter lake productivity anthropogenic impacts