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Mercury bioaccumulation in fish in an artificial lake used to carry out cage culture

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Journal of environmental Sciences 2019年第4期31卷 352-359页

作者： Yongmin Wang Qing Xie Qinqin Xu Jinping Xue Cheng Zhang Dingyong Wang College of resources and environment Southwest University Chongqing Key Laboratory of Agricultural resources and environment

As a global toxic pollutant,mercury(Hg)bioaccumulation within food chain could be influenced by human *** typical fish species were collected from Changshou Lake,an artificial lake used to carry out cage fish culture,to investigate the C/N isotopic compositions and Hg bioaccumulation in *** results showed that the total Hg(THg)and methylmercury(MeHg)levels in fish muscles((56.03±43.96)and(32.35±29.57)ng/g,wet weight),comparable with those in most studies in China,were significantly lower than the international marketing limit(0.5 mg/kg).Past human input for cage culture in this lake led to abnormal^(15)N enrichment in food chain,as the quantitative trophic levels based onδ^(15)N were different with that classified by feeding *** phenomenon subsequently demonstrated that it should be considered thoughtfully with respect to the application of the traditional method for understanding Hg bioaccumulation power by the slope of log_(10)[Hg]withδ^(15)N regression in specific water body(i.e.,Changshou Lake).In addition,no significant linear correlation between Hg and body weight or length of some fish species was observed,suggesting that the fish growth in the eutrophic environment was disproportionate with Hg bioaccumulation,and fish length or weight was not the main factor affecting Hg transfer with food *** occurrence of human disturbance in aquatic system presents a challenge to a better understanding of the Hg bioaccumulation and biomagnification within the food chain.

关键词： Mercury Methylmercury Human disturbed lake Bioaccumulation N enrichment

NUMERICAL SIMULATION OF GROUNDWATER DYNAMICS FOR SONGHUAJIANG RIVER VALLEY IN CHINA

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Journal of Hydrodynamics 2004年第3期16卷 332-335页

作者： ADIL Elkrail College of Water resources and environment

The study area was designed and constructed, based on the simplification of aconceptual model, to develop a three-dimensional groundwater flow model for simulation oftwo-layers system. Finite difference groundwater flow model was constructed for the CentralSonghuajiang River alluvial plain in Northeast China, with the coverage of 786. 6km^2. The gridnetworks with a spacing of 474. 4m by 509. 5m were used to cover the model area. The trial-and-errortechnique was used to calibrate the model. The sensitivity of the simulations to the modelparameters was studied -and the most sensitive parameters that controlling the residual headsdistribution in the Songhuajiang River valley were defined.

关键词： groundwater simulation model sensitivity calibration

Bio-remediation of acephate–Pb(Ⅱ) compound contaminants by Bacillus subtilis FZUL-33

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Journal of environmental Sciences 2016年第7期28卷 94-99页

作者： Wenting Lin Zhen Huang Xuezhen Li Minghua Liu Yangjian Cheng The College of environment and resources Fuzhou University

Removal of Pb^（2＋）and biodegradation of organophosphorus have been both widely investigated respectively. However, bio-remediation of both Pb^（2＋）and organophosphorus still remains largely unexplored. Bacillus subtilis FZUL-33, which was isolated from the sediment of a lake, possesses the capability for both biomineralization of Pb^（2＋）and biodegradation of acephate. In the present study, both Pb^（2＋）and acephate were simultaneously removed via biodegradation and biomineralization in aqueous *** experiments were conducted to study the influence of p H, interaction time and Pb^（2＋）concentration on the process of removal of Pb2＋. At the temperature of 25°C, the maximum removal of Pb^（2＋）by B. subtilis FZUL-33 was 381.31 ± 11.46 mg/g under the conditions of p H 5.5, initial Pb^（2＋）concentration of 1300 mg/L, and contact time of 10 min. Batch experiments were conducted to study the influence of acephate on removal of Pb^（2＋）and the influence of Pb2＋on biodegradation of acephate by B. subtilis FZUL-33. In the mixed system of acephate–Pb2＋, the results show that biodegradation of acephate by B. subtilis FZUL-33 released PO43＋, which promotes mineralization of Pb2＋. The process of biodegradation of acephate was affected slightly when the concentration of Pb2＋was below 100 mg/L. Based on the results, it can be inferred that the B. subtilis FZUL-33 plays a significant role in bio-remediation of organophosphorus-heavy metal compound contamination.

关键词： Acephate–Pb2+ Bacillus subtilis Biodegradation Biomineralization

Uncertainty analysis of hydrological model parameters based on the bootstrap method:A case study of the SWAT model applied to the Dongliao River Watershed,Jilin Province,Northeastern China

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Science China(Technological Sciences) 2014年第1期57卷 219-229页

作者： ZHANG Zheng LU WenXi CHU HaiBo CHENG WeiGuo ZHAO Ying Key Laboratory of Groundwater resources and environment Ministry of Education College of Environment and ResourcesJilin University

As an important tool for the description and analysis of hydrological processes,the watershed hydrological model has been increasingly applied to watershed hydrological simulations and water resource ***,in most cases,model parameters are only determined in a calibration scheme which fits the modeled data to observations,thus significant uncertainties exist in the model *** to quantitatively evaluate the uncertainties in model parameters and the resulting uncertainty impacts on model simulations has always been a question which has attracted much *** this study,two methods based on the bootstrap method(specifically,the model-based bootstrap and block bootstrap)are used to analyze the parameter uncertainties in the case of the SWAT(Soil and Water Assessment Tool)model applied to a hydrological simulation of the Dongliao River ***,the uncertainty ranges of five sensitivity parameters are *** calculated variation coefficients and the variable parameter contributions show that,among the five parameters,ESCO and CN2 have relatively high uncertainties:the variation coefficients and contribution rates are 23.98 and 70%,14.43 and 18%,*** three remaining parameters have relatively low *** compare the two uncertainty ranges of parameters acquired by the two bootstrap methods,and find that the uncertainty ranges of parameters acquired by the block bootstrap are narrower than those acquired by the model-based *** analysis of the effects of parameter uncertainties on the model simulation reveals that the parameter uncertainties have great impacts on results of the model simulation,and in the model calibration stage 60%70%of runoff observations were within the corresponding 95%confidence *** uncertainty in the model simulation during the flood season(*** wet period)is relatively higher than that during the dry season.

关键词： parameters uncertainty analysis hydrological model bootstrap SWAT (Soil and Water Assessment Tool)

Characteristics of volatile compounds removal in biogas slurry of pig manure by ozone oxidation and organic solvents extraction

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Journal of environmental Sciences 2013年第9期25卷 1800-1807页

作者： Yujun Wang Lianshuang Feng Xiaosong Zhao Xiulan Ma Jingmin Yang Huiqing Liu Sen Dou Miping Zhou Zhonglei Xie College of resources and environment Jilin Agricultural University Development College Jilin Agricultural University College of environment and resources Jilin University

Biogas slurry is not suitable for liquid fertilizer due to its high amounts of volatile materials being of complicated composition and peculiar smell. In order to remove volatiles from biogas slurry efficiently, the dynamic headspace and gas chromatography-mass spectrometry were used to clear the composition of volatiles. Nitrogen stripping and superfluous ozone were also used to remove volatiles from biogas slurry. The results showed that there were 21 kinds of volatile compounds in the biogas slurry, including sulfur compounds, organic amines, benzene, halogen generation of hydrocarbons and alkanes, some of which had strong peculiar smell. The volatile compounds in biogas slurry can be removed with the rate of 53.0% by nitrogen stripping and with rate of 81.7% by the oxidization and stripping of the superfluous ozone. On this basis, the removal rate of the volatile compounds reached 99.2% by chloroform and n-hexane extraction, and almost all of odor was eliminated. The contents of some dissolved organic compounds decreased obviously and however main plant nutrients had no significant change in the biogas slurry after being treated.

关键词： biogas slurry dynamic headspace removal volatile compounds plant nutrients

Preparation of nickel nanoparticles in emulsion

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中国有色金属学会会刊：英文版 2008年第1期18卷 212-216页

作者：张有贤付文杰安学勤 College of resources and environment Lanzhou University

The nickel nanoparticles with different sizes and spherical shape were prepared by the reduction of nickel sulfate with sodium borohydride in the water-in-oil emulsions of water/SDBS(sodium dodecylbenzene sulfonate)/n-pentanol/*** effects of aging time,molar ratio of water to SDBS(R)and the concentration of nickel sulfate on the size of particles were *** samples were characterized by transmission electron microscopy(TEM)and inductively coupled plasma spectrometry(ICP).The results show that the average particle size changes from 20 to 40 nm by adjusting aging time(15-30 min)and R(9-11.5).The concentration of nickel sulfate of 1.0 mol/L is the favorite condition.

关键词： W/O乳剂镍乳状液制备方法稀有金属

Effect of dissolved organic matter on adsorption and desorption of mercury by soils

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Journal of environmental Sciences 2008年第9期20卷 1097-1102页

作者： YANG, Yongkui LIANG, Li WANG, Dingyong College of resources and environment Southwest University Chongqing 400716 China Chongqing Key Lab of Agricultural resources and environment Chongqing 400716 China

Effects of dissolved organic matter (DOM) on adsorption and desorption of Hg were investigated in two kinds of soils, Xanthi-Udic Ferralosols (XUF) and Typic Purpli-Udic Cambosols (TPUC). The DOM was obtained from humus soil (DOMH), rice straw (DOMR), and pig manure (DOMP). The presence of DOM obviously reduced Hg maximum adsorption capacity with up to 40% decreases over the control, being an order of DOMH (250.00 mg/kg)< DOMR (303.03 mg/kg) < DOMP (322.58 mg/kg) < CK (control 416.67 mg/kg) for the...

关键词： mercury (Hg) dissolved organic matter (DOM) adsorption desorption

Effect of organic matter and pH on mercury release from soils

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Journal of environmental Sciences 2007年第11期19卷 1349-1354页

作者： YANG Yong-kui ZHANG Cheng SHI Xiao-jun LIN Zao WANG Ding-yong College of resources and environment Southwest University Chongqing 400716 China Chongqing Key Lab of Agricultural resources and environment Chongqing 400716 China

An investigation was conducted on the effect of organic matter （OM） and pH on mercury （Hg） release from soils. Hg release flux was measured using the dynamic flux chamber （DFC） combined with the Lumex multifunctional mercury analyzer in both laboratory experiment and field monitoring. The results showed that Hg emission from the OM-added soils was apparently low because of the high affinity of OM to Hg, resulting in the reverse order as the amount of OM addition. Meanwhile, Hg release flux from different pH value soils exhibited the same trend for both Hg^2＋ and Hg2^2＋ treatment, increasing the Hg flux with pH value of soils increasing. The trend of Hg release in the pH dependence experiment has been well in agreement with that from the field test. In addition, Hg release seemed to be related to its species in the soil, the flux from Hg^2＋-added soil was obviously higher than that of Hg2^2＋-added soil by the laboratory experiment.

关键词： mercury organic matter pH release flux

Surrogate Model Application to the Identification of an Optimal Surfactant-Enhanced Aquifer Remediation Strategy for DNAPL-Contaminated Sites

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Journal of Earth Science 2013年第6期24卷 1023-1032页

作者：罗建男卢文喜辛欣初海波 Key Laboratory of Groundwater resources and environment Ministry of EducationJilin University College of environment and resources Jilin University

A surrogate model is introduced for identifying the optimal remediation strategy for Dense Non-Aqueous Phase Liquids （DNAPL）-contaminated aquifers. A Latin hypercube sampling （LHS） method was used to collect data in the feasible region for input variables. A surrogate model of the multi-phase flow simulation model was developed using a radial basis function artificial neural network （RBFANN）. The developed model was applied to a perchloroethylene （PCE）-contaminated aquifer remediation optimization problem. The relative errors of the average PCE removal rates be- tween the surrogate model and simulation model for 10 validation samples were lower than 5%, which is high approximation accuracy. A comparison of the surrogate-based simulation optimization model and a conventional simulation optimization model indicated that RBFANN surrogate model developed in this paper considerably reduced the computational burden of simulation optimization processes.

关键词： DNAPL Latin hypercube sampling radial basis function artificial neural network si-mulation optimization surrogate model.