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Chinese Journal of Structural Chemistry 2008年第5期27卷 575-587页

作者：冯长君杨伟华沐来龙 School of Chemistry and Chemical Engineering Xuzhou Institute of Technology School of Chemistry and Chemical Engineering Xuzhou Normal University

Based on the characteristics of atom types, Hall＇s electrotopological state indices （En） are calculated for 165 nonionic organic compounds. On the basis of the characteristics of substituent and conjugated matrix, a novel molecular structure parameter （G） is defined and calculated for 165 molecules in this paper. En and G show good structural selectivity for organic molecules. G, a satisfactory relationship between bioconcentration factor （BCF） and En, is expressed as： 1gBCF = -0.283 ＋ 1.246G ＋ 0.079E42 ＋ 0.351E9- 0.063E17 （n＇ = 122, R = 0.967, F = 425.636, s = 0.394）, which could provide estimation and prediction for the lgBCF of nonionic organic chemicals. Furthermore, the model is examined to validate overall robustness with Jackknife tests, and the independent variables in model do not exist cross correlation with VIF. All these regression results show that the new parameter G and electrotopological state index have good rationality and efficiency. It is concluded that the En and G will be used widely in quantitative structure-property/activity relationship （QSPR/QSAR） research.

关键词： nonionic organic compound bioconcentration factor electrotopologicai state index structure parameter QSAR

Linear QSAR Regression Models for the Prediction of bioconcentration factors of Chloroanilines in Fish by Density Functional Theory

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Chinese Journal of Structural Chemistry 2014年第6期33卷 830-834页

作者：冯长君杨伟华 School of Chemistry & Chemical Engineering Xuzhou Institute of Technology School of Chemistry & Chemical Engineering Jiangsu Normal University

Density functional theory（DFT）-B3LYP level with the 6-311G＊＊（d,p） basis set was used to calculate a set of molecular quantum chemical descriptors of 12 chloroanilines. Quantitative structure-activity relationship（QSAR） models of the bioconcentration factors（BCF） of the anilines in fish were established using some of the following calculated descriptors： EHOMO, ENHOMO, ELUMO, ENLUMO, ΔE1（= ELUMO- EHOMO）, ΔE2（= ENLUMO- ENHOMO）, dipole moment（μ）, molecular volume（V）, vibrational energy of 0 K（Ev）, thermodynamic energy（E）, heat capacity（Cv）, entropy（Sm） and the charge of benzene ring（Qph）. Using the variable selection and leaps-and-bounds regression, the quantum chemical descriptors derived directly from the molecular structures were employed to develop a linear QSAR model between the bioconcentration factors（BCF） and two descriptors（Sm, ENHOMO） of 12 chloroanilines. Statistically, the most significant one is a two-parameter linear equation with the correlation coefficient（R^2） of 0.981 and cross-validated correlation coefficient（Rcv^2） of 0.967. The established QSAR model has good stability and predictability based on the results from Rcv2 of leave-one-out cross-validation, AIC, FIT and tα/2. The quantum chemical analyses were performed from two aspects of frontier molecular orbital and entropy. The results show that two structural describers are crucial to the bioconcentration activity of chloroanilines.

关键词： chloroanilines bioconcentration factor density functional theory quantum chemical describers quantitative structure-activity relationship

Differentiated emission control strategy based on comprehensive evaluation of multi-media pollution:Case of mercury emission control

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Journal of Environmental Sciences 2023年第1期123卷 222-234页

作者： Dongwei Lv Qingru Wu Daiwei Ouyang Minneng Wen Gehui Zhang Shuxiao Wang Lei Duan State Key Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084China

In order to comprehensively evaluate the environmental impact of multi-media mercury pollution under differentiated emission control strategies in China,a literature review and case studies were carried *** human exposure to methylmercury was assessed through the dietary intake of residents in areas surrounding a typical coal-fired power plant and a zinc(Zn)smelter,located either on acid soil with paddy growth in southern China,or on alkaline soil with wheat growth in northern *** with knowledge on speciated mercury in flue gas and the fate of mercury in the wastewater or solid waste of the typical emitters applying different air pollution control devices,a simplified model was developed by estimating the incremental daily intake of methylmercury from both local and global *** indicated that air pollution control for coal-fired power plants and Zn smelters can greatly reduce health risks from mercury pollution,mainly through a reduction in global methylmercury exposure,but could unfortunately induce local methylmercury exposure by transferring more mercury from flue gas to wastewater or solid waste,then contaminating surrounding soil,and thus increasing dietary intake via ***,tightening air emission control is conducive to reducing the comprehensive health risk,while the environmental equity between local and global pollution control should be fully *** in the south tends to have higher bioconcentration factors than wheat in the north,implying the great importance of strengthening local pollution control in the south,especially for Zn smelters with higher contribution to local pollution.

关键词： Mercury emission Methylmercury Heavy metal bioconcentration factor Estimated daily intake Health risk assessment

Effects of soil amendments, foliar sprayings of silicon and selenium and their combinations on the reduction of cadmium accumulation in rice

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Pedosphere 2022年第4期32卷 649-659页

作者： Demin LI Hongyan LIU Min GAO Jing ZHOU Jun ZHOU College of Agriculture Guizhou UniversityGuiyang 550025China Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China National Engineering and Technology Research Center for Red Soil Improvement Red Soil Ecological Experiment StationChinese Academy of SciencesLiujiazhan PlantationYingtan 335211China

Agricultural soil contamination by cadmium (Cd) is becoming one of the most serious environmental issues and public concerns. In this study, factorial arrangements of treatments were designed to explore the effects of two soil amendments, sodium sulfide-biofuel ash (SSBA) and lime (0.1%), and three foliar applications, silicon (Si, 2.5 mmol L-1), selenium (Se, 40 mg L-1), and their combination (SS), on Cd reduction in rice (Oryza sativa L.) in a pot experiment, which were then verified in a field experiment. Compared with the control without amendment but with spraying of deionized water, both SSBA and lime significantly reduced concentrations of CaCl2-extractable Cd in soil by 30%–39% and 31%–40% and Cd in brown rice by 44%–63% and 53%–72% in the pot and field experiments, respectively. Foliar Si, Se, and SS applications significantly reduced Cd accumulation in brown rice by 62%–64%, 72%–83%, and 39%–73%, respectively, increased rice grain yield, and improved antioxidant enzyme activities in rice leaves but with different trends in the pot and field experiments. Combinations of SSBA and lime with Si, Se, and SS had a non-significant synergistic effect on Cd reduction in brown rice compared to only foliar spraying or soil amendment in both pot and field experiments, although SSBA + Se and SSBA + Si reduced Cd concentration in brown rice by 16%–34% and 14%–24% compared to only foliar Si and Se and soil SSBA applications, respectively. Soil lime application and foliar Si spraying were the most cost-effective strategies to reduce Cd accumulation in brown rice in the field and pot experiments, respectively. Although soil amendments and foliar treatments were individually effective, their combinations failed to generate a significant synergistic reduction of Cd concentration in brown rice.

关键词： antioxidant enzyme activity bioconcentration factor cadmium bioavailability rice yield soil contamination synergistic effect translocation factor

Chlorobenzenes in waterweeds from the Xijiang River (Guangdong section) of the Pearl River

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Journal of Environmental Sciences 2007年第10期19卷 1171-1177页

作者： DU Qing-ping JIA Xiao-shan HUANG Cai-na Faculty of Environmental Science and Engineering Guangdong University of Technology Guangzhou 510006 China School of Environmental Science and Engineering Sun Yat-sen University Guangzhou 510275 China

The Xijiang River is the major source of water for about 4.5 millions of urban population and 28.7 millions of rural population. The water quality is very important for the health of the rural population. The concentration and distribution of chlorobenzenes （CBs） in both water and waterweeds collected from 4 stations in the Xijiang River （Gangdong section） of the Pearl River in April and November were determined. The result showed that nearly every congener of CBs was detected. The total contents of CBs （ZCBs） in the river water ranged from 111.1 to 360.0 ng/L in April and from 151.9 to 481.7 ng/L in November, respectively. The pollution level of CBs in the water in April was higher than that in November. The contents of ZCBs in waterweeds ranged from 13.53×10^2μg/g to 38.27×10^2μg/g dry weight （dw）. There was no significant difference between April and November in waterweeds. The distribution of CBs in roots, caulis, and leaves of Vallisneria spiralis L. showed different patterns. The leaves mainly contained low-molecular-weight CBs （DCBs）, whereas the roots accumulated more PCBs and HCBs. The average lgBCFlip （bioconcentration factor） of CBs ranged from 0.64 to 3.57 in the waterweeds. The spatial distribution character of CBs in the Xijiang River was： Fengkai County 〈 Yunan County 〈 Yun＇an County 〈 Gaoyao County according to the ZCBs, and the pollution deteriorated from the upstream to the downstream of the Xijiang River. Further analysis demonstrated that the discharge of waste containing CBs may be the main source of CBs pollution in the Xijiang River .

关键词： chlorobenzenes pollution water water weeds distribution bioconcentration factor

Assessing availability, phytotoxicity and bioaccumulation of lead to ryegrass and millet based on 0.1 mol/L Ca(NO_3)_2 extraction

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Journal of Environmental Sciences 2006年第5期18卷 958-963页

作者： SI Ji-tao TIAN Bao-guo WANG Hong-tao Nicholas Basta Jackie Schroder Mark Casillas Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China School of Natural Resources The Ohio State University Columbus OH 43210 USA Department of Plant and Soil Sciences Oklahoma State University Stillwater Oklahoma 74078 USA

This study was conducted to assess availability, phytotoxicity and bioaccumulation of lead （Pb） to ryegrass （Lolium perenne L.） and millet （Echinochloa crusgalli） based on the 0.1 mol/L Ca（NO3）2 extraction. Effect of soil properties on availability, phytotoxicity and bioaccumulation of Pb to the two plants was also evaluated. Five soils with pH values varying from 3.8 to 7.3, organic carbon （OC） contents from 0.7% to 2.4%, and clay contents from 11.6% to 35.6% were selected. Soils were spiked with Pb to achieve a range of concentrations： 250, 500, 1000, 3000 and 5000 mg/kg. Pb availability in the spiked soils was estimated by extracting soil with 0.1 mol/L Ca（NO3）2. The results indicate that plants yield decreased with decreasing soil pH and increased with increasing soil clay and OC content. Negative relationship between available Pb and the relative dry matter growth （RDMG） of the two plants were significantly related. Available Pb used to assess EC20 （20% effective concentration） and EC50 （50% effective concentration） of millet was 119 and 300 mg/kg, respectively. Available Pb used to assess EC20 and EC50 of ryegrass was 63 and 157 mg/kg, respectively. Bioaccumulation, expressed as bioconcentration factors of Pb, was inversely related to soil pH, soil OC and clay content. Strong relationships were found between available lead and uptake by the two plants （P was 0.92 and 0.95 respectively）. In general, 0.1 mol/L Ca（NO3）2 available Pb may be used to assess the availability, phytotoxicity and bioaccumulation of lead to the two plants tested.

关键词： heavy metals bioconcentration factor spike extraction lead (Pb)

An effective planting model to decrease cadmium accumulation in rice grains and plants:Intercropping rice with wetland plants

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Pedosphere 2023年第2期33卷 355-364页

作者： Huimin XIANG Ni LAN Fugang WANG Benliang ZHAO Hui WEI Jiaen ZHANG Guangdong Provincial Key Laboratory of Eco-Circular Agriculture South China Agricultural UniversityGuangzhou 510642(China) Key Laboratory of Agro-Environment in the Tropics Ministry of AgricultureCollege of Natural Resources and EnvironmentSouth China Agricultural UniversityGuangzhou 510642(China) Guangdong Engineering Research Center for Modern Eco-Agriculture and Circular Agriculture Guangzhou 510642(China) Key Laboratory of Agroecology and Rural Environment of Guangdong Regular Higher Education Institutions South China Agricultural UniversityGuangzhou 510642(China)

Cadmium(Cd)pollution affects plant growth and poses a serious threat to food safety and human ***-contaminated rice is assumed to be the main source of Cd exposure to humans,with grave health *** is an efficient,cost-effective,and eco-friendly approach to minimize Cd accumulation in ***,research on the effect of rice intercropping with wetland plants that exhibit great capacity for phytoremediation in decreasing Cd concentrations in paddies is limited.A pot experiment in greenhouse was conducted to evaluate the effect of rice intercropping with two wetland plants(Pontederia cordata and Canna indica)under different soil Cd levels(0,1,10,and 25 mg kg^(-1))on rice growth and Cd accumulation and *** results showed that rice intercropping with the two wetland plants significantly improved plant height,tiller,and biomass of rice,but reduced Cd bioconcentration factors(BCFs)and Cd concentrations in rice and wetland *** with rice monocropping,the BCF in rice grain under 25 mg kg^(-1)soil Cd level significantly decreased by 54.39%and 59.65%in the systems of rice intercropping with *** and ***,*** addition,intercropping inhibited the increase in BCFs in rice and wetland plants under increasing soil Cd *** conclusion,the systems of rice intercropping with *** and *** can be considered two new and effective approaches for ameliorating Cd pollution in paddies,as well as minimizing Cd accumulation in rice and improving food *** the two intercropping systems,rice intercropping with *** performed better than intercropping with ***.

关键词： bioconcentration factor Cd pollution Cd translocation phytoremediation transfer factor

Variation of Cd concentration in various rice cultivars and derivation of cadmium toxicity thresholds for paddy soil by species-sensitivity distribution

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Journal of Integrative Agriculture 2015年第9期14卷 1845-1854页

作者： SONG Wen-en CHEN Shi-bao LIU Ji-fang CHEN Li SONG Ning-ning LI Ning LIU Bin Key Laboratory of Plant Nutrition and Fertilizer Ministry of Agriculture/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural Sciences Agricultural Information Institute Chinese Academy of Agricultural Sciences Institute of Plant Protection and Environmental Protection Beijing Academy of Agricultural and Forestry Science

It is imperative to derive an appropriate cadmium (Cd) health risk toxicity threshold for paddy soils to ensure the Cd con-centration of rice grains meet the food safety standard. In this study, 20 rice cultivars from the main rice producing areas in China were selected, and a pot-experiment was conducted to investigate transformation of Cd in paddy soil-rice system with 0 (CK), 0.3 mg kg–1 (T1) and 0.6 mg kg–1 (T2) Cd treatments in greenhouse. The results showed that Cd concentrations of rice grains existed signiifcant difference (Pfactors (TFs, root to grain and straw to grain) among the tested cultivars were observed in this study. The bioconcentration factors (BCFgrain) and TFs of the 20 rice cultivars were 0.300–1.112 and 0.342–0.817, respectively. The TFs of Cd from straw to grain ranged from 0.366 to 1.71, with signiifcant differences among these 20 rice cultivars. The bioconcentration factors (BCFgrain) and TFs among the 20 rice cultivars ranged from 0.300–1.112 and 0.342–0.817, respectively. The species-sensitivity distribu-tion (SSD) of Cd sensitivity of the rice species could be iftted wel with Burr-III (R2=0.987) based on the data of BCFs. The toxicity threshold of Cd derived from SSD for the paddy soil was 0.507 mg kg–1 in the present study.

关键词： cadmium rice cultivars bioconcentration factor species-sensitivity distribution toxicity thresholds

Phytoavailability of Copper, Zinc and Cadmium in Sewage Sludge-Amended Calcareous Soils

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Pedosphere 2012年第2期22卷 254-262页

作者： LI Qiong GUO Xue-Yan XU Xing-Hua ZUO Yu-Bao WEI Dong-Pu MA Yi-Bing The Key Lab of Resource Environment and GIS the College of Resource Environment and TourismCapital Normal UniversityBeijing 100048(China) Ministry of Agriculture Key Laboratory of Plant Nutrition and Nutrient Cycling Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081(China)

The toxicity of trace elements （TEs）, such as copper （Cu）, zinc （Zn）, and cadmium （Cd）, often restrict land application of sewage sludge （SS） and there was little information about soil-plant transfer of TEs in SS from field experiments in China. In this study pot and field experiments were carried out for 2 years to investigate the phytoavailability of TEs in calcareous soils amended with SS. The results of the pot experiment showed that the phytoavailability of Zn and Cu in the SS was equal to 53.4%-80.9% and 54.8%-91.1% of corresponding water-soluble metal salts, respectively. The results from the field experiment showed that the contents of total Zn, Cu, and Cd in the soils increased linearly with SS application rates. With increasing SS application rates, the contents of Zn and Cu in the wheat grains initially increased and then reached a plateau, while there was no significant change of Cd content in the maize grains. The bioconcentration factors of the metals in the grains of wheat and maize were found to he in the order of Zn 〉 Cu 〉 Cd, but for the straw the order was Cd 〉 Cu 〉 Zn. It was also found that wheat grains could accumulate more metals compared with maize grains. The results will be helpful in developing the critical loads of sewage sludge applied to calcareous soils.

关键词： bioconcentration factor biosolids metal transfer trace elements

Digital mapping of pesticides bioconcentration by integrating remote sensing techniques and plant uptake model

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International Journal of Digital Earth 2023年第1期16卷 2152-2167页

作者： Chenyang Xu Shuangqiao Liao Minghao Lin Qian Yue Jizhe Xia School of Agriculture Sun Yat-sen UniversityGuangdongPeople’s Republic of China Modern Agricultural Innovation Center Henan Institute of Sun Yat-sen UniversityZhumadianPeople’s Republic of China Institute of Tropical and Marine Meteorology People’s Republic of China Meteorological AdministrationGuangzhouPeople’s Republic of China Department of Urban Informatics Shenzhen UniversityShenzhenPeople’s Republic of China

Although pesticides have been widely used worldwide to enhance crop yield and product quality,most pesticides are harmful to the environment and human *** absorb pesticides mainly from air and ***,the soil-plant pathway is essential for pesticide *** factor(BCF)has extensively been applied to evaluate potential plant contamination by pesticides from ***,this study developed a simplified plant transpiration-based plant uptake model(PT-model)to estimate plant pesticides’BCF from soil based on plant *** sensing techniques were employed to generate spatiotemporal continuous plant transpiration via *** BCF mapping was achieved by integrating PT-model with Moderate Resolution Imaging Spectroradiometer(MODIS)remotely sensed *** results were compared with a verified model driven by relative humidity and air temperature(RA-model),which has been confirmed byfindings from previous *** estimated BCF was within the boundaries of the RA-model,indicating the simulation’s overall *** this study,the BCF temporal trend estimated by the proposed method agreed with the RA-model assimilating meteorology datasets,while the spatial distribution was partially ***,the proposed method generates the spatiotemporal patterns of pesticide BCF with relatively consistent results supported by previous records andfindings.

关键词： Pesticide bioconcentration factor evapotranspiration plant uptake model remote sensing