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1.  Alginate modifies the physiological impact of CeO2 nanoparticles in corn seedlings cultivated in soil  
   Lijuan Zhao  Jose R. Peralta-Vide  Bo Peng  Susmita Bandyopadhyay  Baltazar Corral-Diaz  Pedro Osuna-Avil  Milka O. Montes  Arturo A. Keller  Jorge L. Gardea-Torresdey《环境科学学报(英文版)》,2014年第26卷第2期
   Alginates are naturally occurring components of organic matter in natural soil whose effects on nanoparticle (NP) toxicity to plants is not well understood. In the present study, corn plants were grown for one month in soil spiked with 400 mg/kg CeO2 NPs with various alginate concentrations. After one month of growth in the NPs impacted soil, plants were harvested and analyzed for Ce and mineral element concentrations. Chlorophyll concentration and heat shock protein 70, used as biomarkers for oxidative stress, were also evaluated. Results showed that, compared to CeO2 NPs treatment, alginate at 10, 50, and 100 mg/kg increased Ce concentration in roots by approximately 46%, 38%, and 29% and by 115%, 45%, and 56% in shoots, respectively. CeO 2 NPs without alginate increased Mn accumulation in roots by 34% compared to control. CeO2 NPs with low and medium alginate increased Mn by ca. 92% respect to NPs without alginate and by ca. 155% respect to control. CeO2 NPs without/with alginate significantly increased accumulation of Fe and Al in roots. In addition, alginate at 50 mg/kg increased Zn accumulation in roots by 52% compared to control. In shoots, K increased at all NP treatments but the accumulation of other elements was not affected. Alginate enlarged the impact of CeO2 NPs to corn plants by reducing chlorophyll a content and triggering overexpression of heat shock protein 70.    

2.  Preliminary investigation on cytotoxicity of fluorinated polymer nanoparticles  
   Xue Wang  Wenge Cheng  Qiuyuan Yang  Hongyun Niu  Qian Liu  Yun Liu  Ming Gao  Ming Xu  An Xu  Sijin Liu  Xiaoyu Huang  Yuguo Du《环境科学学报(英文版)》,2018年第69卷第7期
   As well-known persistent organic pollutants(POPs), organofluorine pollutants such as perfluorooctane sulfonate(PFOS) have been proven to be bioaccumulated and harmful to health. However, toxicological assessment of organofluorinated nanoparticles, which have emerged as a novel tool for biomedical and industrial applications, is lacking, to the best of our knowledge. To assess the biological effects and health risk of fluorinated nanoparticles,trifluoroethyl aryl ether-based fluorinated poly(methyl methacrylate) nanoparticles(PTFEPMMA NPs) were synthesized with various fluorine contents(PTFE-PMMA-1 NPs 12.0 wt.%,PTFE-PMMA-2 NPs 6.1 wt.% and PTFE-PMMA-3 NPs 5.0 wt.%), and their cytotoxicity was investigated in this study. The in vitro experimental results indicated that the cytotoxicity of PTFE-PMMA NPs was mild, and was closely related to their fluorine(F) contents and Fcontaining side chains. Specifically, the cytotoxicity of PTFE-PMMA NPs decreased with increasing F content and F-containing side chains. After exposure to PTFE-PMMA NPs at a sublethal dose(50 μg/m L) for 24 hr, the phospholipid bilayer was damaged, accompanied by increasing permeability of the cell membrane. Meanwhile, the intracellular accumulation of reactive oxygen species(ROS) occurred, resulting in the increase of DNA damage, cell cycle arrest and cell death. Overall, the PTFE-PMMA NPs were found to be relatively safe compared with typical engineered nanomaterials(ENMs), such as silver nanoparticles and graphene oxide, for biomedical and industrial applications.    

3.  Secondary effect of SO_2 pollution: enhanced growth of the army worm, Mythimna separata (Walker)  
   Wu Kunjun  Gong Peiyu  Li Xiuzhen  Shu Jianmin and Cao HongfaInstitute of Zookogy  Academia Sinica  Beijing 100080  ChinaInstitute of Zookogy  Chinese Research Academy of Environmental Science  Beijing 100012  China《环境科学学报(英文版)》,1990年第4期
   Effects of SO2 pollution on growth of the army worm, Mythimna separata, were investigated by rearing the larvae for 12 days on the wheat plants being exposed to SO2 levels ranged from 50 to 200 ppb in the field open-top fumigation devices. Larval period shortened while their mean relative growth rate (MRGR) increased as SO2 dose elevated. Similar experiment with the insect on the artificial diet excluded the possibility that SO2 pollution directly stimulated growth of the army worm.The patterns of change in amino acid hydrolysates in the host foliage suggested that contents of methionine, and perhaps, arginine in food material exposed to unpolluted air were at such levels that they could only support sub-optimum growth of the insect, and SO2 pollution increased concentrations of these limiting amino acids, resulting in better performance of the larvae.    

4.  Assessing availability, phytotoxicity and bioaccumulation of lead to ryegrass and millet based on 0.1 mol/L Ca(NO3)2 extraction  被引次数:1
   SI Ji-tao  TIAN Bao-guo  WANG Hong-tao  Nicholas Bast  Jackie Schroder  Mark Casillas《Journal of environmental sciences (China)》,2006年第18卷第5期
   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.    

5.  Effects of arsenic on seed germination and physiological activities of wheat seedlings  被引次数:4
   LI Chun-xi  FENG Shu-li  SHAO Yun  JIANG Li-n  LU Xu-yang  HOU Xiao-li《环境科学学报(英文版)》,2007年第19卷第6期
   The effects of arsenic (As) were investigated on seed germination, root and shoot length and their biomass and some other factors to elucidate the toxicity of As. The results showed low concentrations of As (0-1 mg/kg) stimulated seed germination and the growth of root and shoot, however, these factors all decreased gradually at high concentrations of As (5-20 mg/kg). The contents of O2^-, MDA, soluble protein and peroxidase (POD) activity all increased with increasing As concentrations. Soluble sugar content, ascorbate peroxidase (APX), and superoxide dismutase (SOD) activities decreased at low concentrations of As, and increased at high concentrations of As. While acetylsalicylic acid (ASA) and chlorophyll contents, catalase (CAT) activity displayed increasing trend when the concentrations of As was lower than 1 mg/kg, and then decreasing trend. By polyacrylamide gel electrophoresis (PAGE), As induced the expression of POD isozymes of wheat seedlings. As induced the expression of CAT isozymes but inhibited the expression of SOD isozymes of wheat seedlings at concentrations lower than 1 mg/kg. However, As inhibited the expression of CAT isozymes but induced the expression of SOD isozymes at concentrations higher than 5 mg/kg. The results indicated As could exert harmfulness in the early development stage of wheat at inappropriate concentrations.    

6.  Effects of cerium on growth and physiological mechanism in plants under enhanced ultraviolet-B radiation  被引次数:1
   LIANG Chan-juan  HUANG Xiao-hu  TAO Wen-yi  ZHOU Qing《Journal of environmental sciences (China)》,2006年第18卷第1期
   Effect of cerium (Ce^3+) on the growth, photosynthesis and antioxidant enzyme system in rape seedlings (Brassica juncea L.) exposed to two levels of UV-B radiation (T1: 0.15 W/m^2 and T2:0.35 W/m^2) was studied by hydroponics under laboratory conditions. After 5 d of UV-B treatment, the aboveground growth indices were obviously decreased by 13.2%-44. 1%(T1) and 21.4%-49.3% (T2), compared to CK, and except active absorption area of roots, the belowground indices by 14.1%-35.6%(T1) and 20.3%-42.6% (T2). For Ce+UV-B treatments, the aboveground and belowground growth indices were decreased respectively by 4.1%-23.6%, 5.2% -23.3%(Ce+T1) and 10.8%-28.4%, 7.0%-27.8%(Ce+T2), lower than those of UV-B treatments. The decrease of growth indices appeared to be the result of changes of physiological processes. Two levels of UV-B radiation induced the decrease in chlorophyll content, net photosynthesis rate, transpiration rate, stomatal conductance and water use efficiency by 11.2%-25.9%(T1) and 20.9%- 56.9%(T2), whereas increase in membrane permeability and activities of antioxidant enzymes including superoxide dismutase(SOD), catalase (CAT) and peroxidase (POD) by 6.9%, 22.8%, 21.5%, 9.5%(T1) and 36.6%, 122.3%, 103.5%, 208.9%(T2), respectively. The reduction of the photosynthetic parameters in Ce+UV-B treatments was lessened to 3.2%-13.8%(Ce+T1) and 4.9%-27.6%(Ce+T2), and the increase of membrane permeability and activities of antioxidant enzymes except POD in the same treatments were lessened to 2.4%, 8.4%, 6.6%(Ce+T1) and 30.1%, 116.7%, 75.4%(Ce+T2). These results indicate that the regulative effect of Ce on photosynthesis and antioxidant enzymatic function is the ecophysiological basis of alleviating the suppression of UV-B radiation on growth of seedlings. Furthermore, the protective effect of Ce on seedlings exposed to TI level of UV-B radiation is superior to T2 level.    

7.  Cadmium pollution enhanced ozone damage to winter wheat: biochemical andphysiological evidences  
   Yong Li  Caihong Li  Yanhai Zheng  Guanglei Wu  Tana Wuyun  Hong Xu  Xinhua He  Gaoming Jiang《环境科学学报(英文版)》,2011年第23卷第2期
   Combined e ects of ozone (O3) and cadmium (Cd) on growth and physiology of winter wheat (Triticum aestivum L. cv. JM22)were determined. Wheat plants were grown without or with Cd and exposed to charcoal-filtered air (< 10 ppb O3) or elevated O3(80 5 ppb, 7 hr/day) for 20 days. Results showed that O3 considerably depressed light saturated net photosynthetic rate (–20%),stomatal conductance (–33%), chlorophyll content (–33%), and total biomass (–29%) without Cd. The corresponding decreases werefurther enhanced by 45%, 56%, 60% and 59%, respectively with Cd, indicating a synergistic e ect of O3 and Cd on wheat. Ozonesignificantly increased the activity of superoxide dismutase (46%), catalase (48%) and peroxidase (56%). However, great increasesin malondialdehyde (MDA) content (2.55 folds) and intercellular CO2 concentration (1.13 folds) were noted in O3+Cd treatmentcompared to control. Our findings demonstrated that the increased anti-oxidative activities in wheat plants exposed to O3+Cd mightnot be enough to overcome the adverse e ects of the combination of both pollutants as evidenced by further increase in MDA content,which is an important indicator of lipid peroxidation. Precise prediction model on O3 damages to crop should be conducted to ensureagricultural production security by considering environmental constraints in an agricultural system in peri-urban regions.    

8.  Influences of excessive Cu on photosynthesis and growth in ectomycorrhizal Pinus sylvestris seedlings  被引次数:5
   Huang Y  Tao S《Journal of environmental sciences (China)》,2004年第16卷第3期
   Growth and photosynthesis responses were measured for Scots pine( Pinus sylvestris L. cv. ) inoculated with ectomycorrhizal fungi ( Suillus bovinus ) under 6.5 and 25 mg/L Cu treatments to evaluate ectomycorrhizal seedlings‘ tolerance to heavy metal stress. Results showed that excessive Cu can significantly impair the growth and photosynthesis of pine seedlings, but such impairment is much smaller to the ectomycorrhizal seedlings. Under 25mg/L Cu treatment, the dry weight of ectomycorrhizal seedlings is 25% lower than the control in contrary to 53% of the non-mycorrhizal seedlings, and the fresh weight of ectomycorrhizal roots was significantly higher than those of non-mycorrhizal roots, about 25% and 42% higher at 6.5 and 25 mg/L Cu treatments respectively. Furthermore,ectomycorrhizal fungi induced remarkable difference in the growth rate and pigment content of seedlings under excessive Cu stress. At 2.5 mg/L Cu, the contents of total chlorophyll, chlorophyll-a and chlorophyll-b were 30% higher in ectomycorrhizal plants than those in non-mycorrhizal plants. O2 evolution and electron transport of PSI and PSII were restrained by elevated Cu stress. However, no significant improvement was observed in reducing the physiological restraining in ectomycorrhizal seedlings over the non-mycorrhizal ones.    

9.  Combined effects of cadmium and fluoranthene on germination, growth and photosynthesis of soybean seedlings  被引次数:1
   Qiushuang Li  Yonglong Lu  Yajuan Shi  Tieyu Wang  Kun Ni  Li Xu  Shijie Liu  Lin Wang  Qinli Xiong  John. P Giesy《环境科学学报(英文版)》,2013年第25卷第9期
   The single and combinational effects of cadmium (Cd) and fluoranthene (FLT) on germination, growth and photosynthesis of soybean seedlings were investigated. Exposure to 5, 10, or 15 mg Cd/L or 1, 5, or 10 mg FLT/L individually or in combination significantly decreased germination vigor (3 days) and final germination rate of soybean seeds, except at 1 and 5 mg FLT/L. The results of two-way ANOVA analysis and the Bliss independence model showed that at lower concentrations of FLT (1 mg/L), the interaction between Cd and FLT on germination was antagonistic, whereas the interaction was synergistic when the concentration of FLT was 5 or 10 mg/L and the concentration of Cd was 15 mg/L. Growth, expressed as dry weight, length of shoot and root, leaf area, and photosynthesis, expressed as net photosynthetic rate, intercellular CO2 concentration, chlorophyll contents and fluorescence of soybean seedlings were also reduced by exposure to 5 or 10 mg Cd/L or 1 or 5 mg FLT/L, singly or jointly. Significant antagonistic effects of exposure to 5 or 10 mg Cd/L or 1 or 5 mg FLT/L on shoot growth and photosynthesis were observed, whereas synergy and antagonism of Cd and FLT were both observed for root growth.    

10.  Development of a novel myconanomining approach for the recovery of agriculturally important elements from jarosite waste  
   Ankita Bedi  Braj Raj Singh  Sunil K. Deshmukh  Nisha Aggarwal  Colin J. Barrow  Alok Adholeya《环境科学学报(英文版)》,2018年第67卷第5期
   In this study, an ecofriendly and economically viable waste management approach have been attempted towards the biosynthesis of agriculturally important nanoparticles from jarosite waste. Aspergillus terreus strain J4 isolated from jarosite(waste from Debari Zinc Smelter,Udaipur, India), showed good leaching efficiency along with nanoparticles(NPs) formation under ambient conditions. Fourier-transform infrared spectroscopy(FT-IR) and transmission electron microscopy(TEM) confirmed the formation of NPs. Energy dispersive X-ray spectroscopy(EDX analysis) showed strong signals for zinc, iron, calcium and magnesium,with these materials being leached out. TEM analysis and high resolution transmission electron microscopy(HRTEM) showed semi-quasi spherical particles having average size of 10‐50 nm. Thus, a novel biomethodology was developed using fungal cell-free extract for bioleaching and subsequently nanoconversion of the waste materials into nanostructured form. These biosynthesized nanoparticles were tested for their efficacy on seed emergence activity of wheat(Triticum aestivum) seeds and showed enhanced growth at concentration of 20 ppm. These nanomaterials are expected to enhance plant growth properties and being targeted as additives in soil fertility and crop productivity enhancement.    

11.  Nanoparticles in mitigating gaseous emissions from liquid dairy manure stored under anaerobic condition  
   Niloy Chandra Sarker  Shafiqur Rahman  Md.Saidul Borhan  Parthiban Rajasekaran  Swadeshmukul Santra  Ali Ozcan《环境科学学报(英文版)》,2019年第2期
   A number of mitigation techniques exist to reduce the emissions of pollutant gases and greenhouse gases(GHGs) from anaerobic storage of livestock manure. Nanoparticle(NP)application is a promising mitigating treatment option for pollutant gases, but limited research is available on the mode of NP application and their effectiveness in gaseous emission reduction. In this study, zinc silica nanogel(ZnSNL), copper silica nanogel(CuSNL), and N-acetyl cysteine(NACL) coated zinc oxide quantum dot(Qdot) NPs were compared to a control lacking NPs. All three NPs tested significantly reduced gas production and concentrations compared to non-treated manure. Overall, cumulative gas volumes were reduced by 92.73%–95.83%, and concentrations reduced by 48.98%–99.75% for H_2S, and 20.24%–99.82% for GHGs. Thus, application of NPs is a potential treatment option for mitigating pollutant and GHG emissions from anaerobically stored manure.    

12.  Coupled effects of methane monooxygenase and nitrogen source on growth and poly-β-hydroxybutyrate (PHB) production of Methylosinus trichosporium OB3b  
   Tingting Zhang  Jiti ZhouXiaowei Wang  Yu Zhang《环境科学学报(英文版)》,2017年第29卷第2期
   The coupled effects of nitrogen source and methane monooxygenase (MMO) on the growth and poly-β-hydroxybutyrate (PHB) accumulation capacity of methanotrophs were explored. The ammonia-supplied methanotrophs expressing soluble MMO (sMMO) grew at the highest rate, while N2-fixing bacteria expressing particulate MMO (pMMO) grew at the lowest rate. Further study showed that more hydroxylamine and nitrite was formed by ammonia-supplied bacteria containing pMMO, which might cause their slightly lower growth rate. The highest PHB content (51.0%) was obtained under nitrogen-limiting conditions with the inoculation of nitrate-supplied bacteria containing pMMO. Ammonia-supplied bacteria also accumulated a higher content of PHB (45.2%) with the expression of pMMO, while N2-fixing bacteria containing pMMO only showed low PHB production capacity (32.1%). The maximal PHB contents of bacteria expressing sMMO were low, with no significant change under different nitrogen source conditions. The low MMO activity, low cell growth rate and low PHB production capacity of methanotrophs continuously cultivated with N2 with the expression of pMMO were greatly improved in the cyclic NO3 N2 cultivation regime, indicating that long-term deficiency of nitrogen sources was detrimental to the activity of methanotrophs expressing pMMO.    

13.  Preparation and characterization of Pd/Fe bimetallic nanoparticles immobilized on Al2O3/PVDF membrane: Parameter optimization and dechlorination of dichloroacetic acid  
   Lijuan Zhang  Zhaohong Meng  Shuying Zang《环境科学学报(英文版)》,2015年第27卷第5期
   Using a liquid-solid phase inversion method, a hybrid matrix poly(vinylidene fluoride) (PVDF) membrane was prepared with alumina (Al2O3) nanoparticle addition. Pd/Fe nanoparticles (NPs) were successfully immobilized on the Al2O3/PVDF membrane, which was characterized by Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The micrographs showed that the Pd/Fe NPs were dispersed homogeneously. Several important experimental parameters were optimized, including the mechanical properties, contact angle and surface area of Al2O3/PVDF composite membranes with different Al2O3 contents. At the sametime, the ferrous ion concentration and the effect of hydrophilization were studied. The results showed that the modified Al2O3/PVDF membrane functioned well as a support. The Al2O3/PVDF membrane with immobilized Pd/Fe NPs exhibited high efficiency in terms of dichloroacetic acid (DCAA) dechlorination. Additionally, a reaction pathway for DCAA dechlorination by Pd/Fe NPs immobilized on the Al2O3/PVDF membrane system was proposed.    

14.  Persistence and growth of faecal culturable bacterial indicators in watercolumn and sediments of Vidy Bay, Lake Geneva, Switzerland  
   POTE John  HALLER Laurence  KOTTELAT R′egis  SASTRE Vincent  ARPAGAUS Philippe  WILDI Walter《环境科学学报(英文版)》,2009年第21卷第1期
   The aims of this study was to investigate the persistence and the growth of culturable bacterial indicators (CBI) including totalcoliforms (TC) and faecal coliforms represented by Escherichia coli, enterococcus (ENT), and aerobic mesophilic bacteria (AMB) inthe surface sediments and the water column of Vidy Bay (Lake Geneva, City of Lausanne, Switzerland). The study was carried out for60 d using microcosms containing Sewage Treatment Plant (STP) e uent and nonsterile water without CBI, as well as contaminatedand non-contaminated sediments. The e ects of water temperature and of organic matter associated with sediments on the survival ofCBI in the sediments and the water column were observed. The number of CBI colonies in the contaminated sediments of Vidy Bay andin the STP e uent was almost identical in the order of 105–107, 104–106, 103–105, and 104–107 CFU/100 g sediment or /100 mL waterfor TC, E. coli, ENT, and AMB respectively. A degradation of CBI was observed in the sediments where organic mater content waslow and in the water column at a temperature of 10°C after 5 d of experimentation. In addition, a growth of CBI was observed in thesediment which is rich in organic matter at 20°C. The results of this study indicate: (1) the higher concentrations of the CBI observedin di erent points in the water column of Vidy Bay may not be explained only by the recent contribution of the three potential sourcesof the Bay contamination including STP and the Chamberonne and Flon Rivers, but also by the persistence, removal from sedimentand multiplication of CBI in the sediment and water column; (2) the sediment of Vidy Bay constitute a reservoir of CBI and can evensupport their growth; and (3) the CBI not only survive in sediments, but also can be remobilized and increased in the water column,therefore, it become a permanent microbiological pollution in Vidy Bay.    

15.  Effects of simulated acid rain on root growth of Cunninghamia lanceolata and Schima superba saplings planted in acidified soil  
   Liao Liping and Chen ChuyingInstitute of Applied Ecology  Academia Sinica  Shengyang 110015  China《环境科学学报(英文版)》,1991年第2期
   Results from pot culture (with one-year old Cunninghamia lanceolata and Schima superba) are described. It was found that the biomass production and elongation of C. lanceolata was seriously inhibited at pH 2.0 rain, but for S. superba, was not affected markedly. When pH values of experimental rain were higher than 2.0, the root growth of both species was not adversely affected. Aluminium had already accumulated to some degrees in the roots of both trees, and started to affect the root growth of C. lanceolata at pH 2.0 rain. The soil chemistry was also examined. Increased acidity of experimental rain increased the leaching of Ca and Mg. The Al/Ca mol ratio increased from 0.3 to 0.9 in top soil, and in rhizosphere to 1.5 when the pH values of simulated acid rain were 4.5 to 2.0. In this experiment, NO3- fertilization effect was discovered.    

16.  Effects of municipal piers on the growth of juvenile fishes in the Hudson River estuary: a study across a pier edge  
   J. T. Duffy-Anderson  K. W. Able《Marine Biology》,1999年第133卷第3期
   The growth rates of two fish species, the winter flounder Pseudopleuronectes americanus (Walbaum) (19.3 to 42.6 mm total length, TL) and the tautog Tautogaonitis (Linnaeus) (23.9 to 55.9 mm TL), were used to evaluate habitat quality under and around municipal piers in the Hudson River estuary, USA. Growth rates were measured in a series of 10 d field caging-experiments conducted at two large piers in the summers of 1996 and 1997. Cages (0.64 m2) were deployed along␣transects that stretched from underneath the piers to beyond them, encompassing the pier edge (the transitional zone between the pier interior and the outside). Growth in weight (G w ) was determined at five locations along the transect, 40 m beneath the pier, 20 m beneath the pier, at the pier edge, 20 m beyond the pier edge, and 40 m beyond. Under piers, mean growth rates of winter flounder and tautogs were negative (xˉG W  = −0.02 d−1), and rates were comparable to laboratory-starved control fishes (xˉG W  = −0.02 d−1). In contrast, mean growth rates at pier edges and in open waters beyond piers were generally positive (xˉG W ranged from −0.001 to +0.05 d−1), with growth at pier edges often being more variable and less rapid than at open-water sites. Analyses of stomach contents upon retrieval of caged fishes revealed that dry weights of food were generally higher among fishes caged at open-water stations ( range = 0.02 to 0.72 mg dry wt) than at pier-edge ( range = 0.01 to 0.54 mg) or under-pier ( range = 0.03 to 0.11 mg) stations, although it was apparent that benthic prey were available at all stations on the transect. Our results indicate poor feeding conditions among fishes caged under piers, and suboptimal foraging among fishes caged at pier edges. Inadequate growth rates can lead to higher rates of mortality, and, based on these and other earlier experiments, we conclude that under-pier environments are poor-quality habitats for some species of juvenile fishes. Received: 12 March 1998 / Accepted: 9 November 1998    

17.  Response of successive three generations of cotton,bollworm,Helicoverpa armigera (Hübner),fed on cotton bolls under elevated CO_2  
   WU Gang CHEN Fa-jun SUN Yu-cheng GE Feng 1.National Key Laboratory of Integrated Management of Pest Insects and Rodents  Institute of Zoology  Chinese Academy of Sciences  Beijing 100101  China. 2.Department of Biology  Wuhan University of Technology  Wuhan 430070  China《环境科学学报(英文版)》,2007年第11期
   The growth,development and consumption of successive three generations of cotton bollworm,Helicoverpa armigera(Hübner),fed on cotton bolls grown under elevated CO_2(double-ambient vs.ambient)in open-top chambers were examined.Significant decreases in protein,total amino acid,water and nitrogen content and increases in free fatty acid were observed in cotton bolls.Changes in quality of cotton bolls affected the growth,development and food utilization of H.armigera.Significantly longer larval development duration in three successive generations and lower pupal weight of the second and third generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO_2.Significantly lower fecundity was also found in successive three generations of H.armigera fed on cotton bolls grown under elevated CO_2.The consumption per larva occurred significant increase in successive three generations and frass per larva were also significantly increased during the second and third generations under elevated CO_2.Significantly lower relative growth rate,efficiency of conversion of ingested food and significant higher relative consumption rate in successive three generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO_2.Significantly lower potential female fecundity,larval numbers and population consumption were found in the second and third generations of cotton bollworm fed on cotton bolls grown under elevated CO_2.The integrative effect of higher larval mortality rate and lower adult fecundity resulted in significant decreases in potential population consumption in the latter two generations.The results show that elevated CO_2 adversely affects cotton bolls quality,which indicates the potential population dynamics and potential population consumption of cotton bollworm will alleviate the harm to the plants in the future rising CO_2 atmosphere.    

18.  Response of successive three generations of cotton bollworm, Helicoverpaarmigera (Hübner), fed on cotton bolls under elevated CO2  被引次数:1
   WU Gang  CHEN Fa-jun  SUN Yu-cheng  GE Feng《环境科学学报(英文版)》,2007年第19卷第11期
   The growth, development and consumption of successive three generations of cotton bollworm, Helicoverpa armigera (Htibner), fed on cotton bolls grown under elevated CO2 (double-ambient vs. ambient) in open-top chambers were examined. Significant decreases in protein, total amino acid, water and nitrogen content and increases in free fatty acid were observed in cotton bolls. Changes in quality of cotton bolls affected the growth, development and food utilization of H. armigera. Significantly longer larval development duration in three successive generations and lower pupal weight of the second and third generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower fecundity was also found in successive three generations of H. armigera fed on cotton bolls grown under elevated CO2. The consumption per larva occurred significant increase in successive three generations and frass per larva were also significantly increased during the second and third generations under elevated CO2. Significantly lower relative growth rate, efficiency of conversion of ingested food and significant higher relative consumption rate in successive three generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower potential female fecundity, larval numbers and population consumption were found in the second and third generations of cotton bollworm fed on cotton bolls grown under elevated CO2. The integrative effect of higher larval mortality rate and lower adult fecundity resulted in significant decreases in potential population consumption in the latter two generations. The results show that elevated CO2 adversely affects cotton bolls quality, which indicates the potential population dynamics and potential population consumption of cotton bollworm will alleviate the harm to the plants in the future rising CO2 atmosphere.    

19.  Pure and Mg-doped self-assembled ZnO nano-particles for the enhanced photocatalytic degradation of 4-chlorophenol  
   N. Clament Sagaya Selvam  S. Narayanan  L. John Kennedy  J. Judith Vijaya《环境科学学报(英文版)》,2013年第25卷第10期
   A novel self-assembled pure and Mg doped ZnO nano-particles (NPs) were successfully synthesized by a simple low temperature co-precipitation method. The prepared photocatalysts were characterized by X-ray diffraction, high resolution scanning electron mi- croscopy, high resolution transmission electron microscopy, diffuse reflectance spectroscopy and photoluminescence (PL) spectroscopy. The results indicated that the prepared photocatalysts showed high crystallinity with a uniform size distribution of the NPs. The degradation of cholorphenols is highly mandatory in today's scenario as they are affecting the environment adversely. Thus, the photocatalytic degradation of 4-chlorophenol (4-CP), a potent endocrine disrupting chemical in aqueous medium was investigated by both pure and Mg-doped ZnO NPs under UV-light irradiation in the present study. The influence of the Mg content on the structure, morphology, PL character and photocatalytic activity of ZnO NPs were investigated systematically. Furthermore,the effect of different parameters such as 4-CP concentration, photocatalyst amount, pH and UV-light wavelength on the resulting photocatalytic activity was investigated.    

20.  Effects of nitrogen and phosphorus concentrations on the bioaccumulation of polybrominated diphenyl ethers by Prorocentrum donghaiense  
   Chao Chai  Xundong Yin  Wei Ge  Jinye Wang《环境科学学报(英文版)》,2013年第25卷第2期
   The growth, cellular total lipids, bioaccumulation amount, and bioaccumulation factors (BAFs) of 2,4,4 ′ -tribromodiphenyl ether (BDE28), 2,2 ′ ,4,4 ′ -tetrabromodiphenyl ether (BDE47), and 2,2 ′ ,4,4 ′ ,5-pentabromodiphenyl ether (BDE99) in a semi-continuous culture of Prorocentrum donghaiense were studied in relation to nitrate (0, 128, and 512 μmol/L) and phosphate (0, 8, and 32 μmol/L) concentrations. The BDE28, BDE47, and BDE99 content per cell under 0 μmol N/L were 3.77 × 10 6 , 3.95 × 10 6 , and 4.32 × 10 6 ng/cell, respectively, which were significantly higher than those under 128 and 512 μmol N/L. A nearly 5-fold increase in polybrominated diphenyl ether (PBDE) content per algal cell was found between 0 and 8 μmol P/L and between 8 and 32 μmol P/L. With increasing N and P concentrations, the PBDE content per volume of algal culture and the accumulation percentage of available PBDEs declined slightly. The BAFs for the PBDEs based on lipids showed that the logBAF lip under 0 μmol N/L was higher than those under 128 and 512 μmol N/L. The logBAF lip under 0 μmol P/L was higher than that under 8 μmol P/L but lower than that under 32 μmol P/L. Correlation analysis indicated a significant negative correlation between nutrient concentration and cellular total lipids, as well as the PBDE content per cell. The results indicate that different N and P concentrations change the total lipids content of P. donghaiense, thereby resulting in varying PBDE accumulation.    

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