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Spatiotemporal distribution of carbonyl compounds in China 全文
2015
Ho, K.F. | Ho, Steven Sai Hang | Huang, R.-J. | Dai, W.T. | Cao, J.J. | Tian, Linwei | Deng, W.J.
A sampling campaign was carried out at nine Chinese cities in 2010/2011. Fifteen monocarbonyls (C# = 1–9) were quantified. Temperature is the rate-determining factor of the summertime carbonyl levels. The carbonyl emissions in winter are mainly driven by the primary anthropogenic sources like automobile. A molar ratio of propionaldehyde to nonaldehyde is a barometer of the impact of atmospheric vegetation emission which suggesting that strong vegetation emissions exist in summer and high propionaldehyde abundance is caused by fossil fuel combustion in winter. Potential health risk assessment of formaldehyde and acetaldehyde was conducted and the highest cumulative risks were observed at Chengdu in summer and Wuhan in winter. Because of the strong photochemical reaction and large amount of anthropogenic emissions, high concentrations of carbonyl compounds were observed in Chengdu. The use of ethanol-blended gasoline in Wuhan is the key reason of acetaldehyde emission and action should be taken to avoid potential health risks.
显示更多 [+] 显示较少 [-]Searching for native tree species and respective potential biomarkers for future assessment of pollution effects on the highly diverse Atlantic Forest in SE-Brazil 全文
2015
Domingos, Marisa | Bulbovas, Patricia | Camargo, Carla Z.S. | Aguiar-Silva, Cristiane | Brandão, Solange E. | Dafré-Martinelli, Marcelle | Dias, Ana Paula L. | Engela, Marcela R.G.S. | Gagliano, Janayne | Moura, Barbara B. | Alves, Edenise S. | Rinaldi, Mirian C.S. | Gomes, Eduardo P.C. | Furlan, Claudia M. | Figueiredo, Ana Maria G.
This study summarizes the first effort to search for bioindicator tree species and respective potential biomarkers for future assessment of potential mixed pollution effects on the highly diverse Atlantic Forest in SE-Brazil. Leaves of the three most abundant species inventoried in a phytosociological survey (Croton floribundus, Piptadenia gonoacantha and Astronium graveolens) were collected in four forest remnants during winter and summer (2012). Their potential bioindicator attributes were highlighted using a screening of morphological, chemical and biochemical markers. The leaf surface structure and/or epicuticular wax composition pointed the accumulator properties of C. floribundus and P. gonoacantha. C. floribundus is a candidate for assessing potential accumulation of Cu, Cd, Mn, Ni, S and Zn. P. gonoacantha is a candidate to monitor polycyclic aromatic hydrocarbons. Increased levels of secondary metabolites and decreased antioxidant capacity in leaves of A. graveolens may support its value as a bioindicator for oxidative pollutants by visible dark stipplings.
显示更多 [+] 显示较少 [-]Inorganic nitrogen wet deposition: Evidence from the North-South Transect of Eastern China 全文
2015
Zhan, X. | Yu, G. | He, N. | Jia, B. | Zhou, M. | Wang, C. | Zhang, J. | Zhao, G. | Wang, S. | Liu, Y. | Yan, J.
We examined the spatio-temporal variation of dissolved inorganic nitrogen (DIN) deposition in eight typical forest ecosystems of Eastern China for three consecutive years. DIN deposition exhibited an increasing gradient from north to south, with N−NH4+ as the predominant contributor. DIN deposition in precipitation changed after interaction with the forest canopy, and serious ecological perturbations are expected in this region. DIN deposition presented seasonal fluctuations, which might be ascribed to agricultural activity, fossil-fuel combustion and environmental factors (i.e., wind direction, soil temperature). Notably, N fertilizer use (FN), energy consumption (E), and precipitation (P) jointly explained 84.3% of the spatial variation in DIN deposition, of which FN (27.2%) was the most important, followed by E (24.8%), and finally P (9.3%). The findings demonstrate that DIN deposition is regulated by precipitation mainly via anthropogenic N emissions, and this analysis provides decision-makers a novel view for N pollution abatement.
显示更多 [+] 显示较少 [-]Accumulation of atmospheric deposition of As, Cd and Pb by bush bean plants 全文
2015
De Temmerman, L. | Waegeneers, N. | Ruttens, A. | Vandermeiren, K.
Bush bean (Phaseolus vulgaris) was exposed to atmospheric deposition of As, Cd and Pb in a polluted and a reference area. The atmospheric deposition of these elements was significantly related to the concentrations in leaves, stems and pods at green harvest. Surprisingly there was also a clear relation for As and Pb in the seeds at dry harvest, even though these seeds were covered by the husks. Root uptake of accumulated atmospheric deposits was not likely in such a short term experiment, as confirmed by the fact that soil pore water analysis did not reveal significant differences in trace element concentrations in the different exposure areas. For biomonitoring purposes, the leaves of bush bean are the most suitable, but also washed or unwashed pods can be used. This means that the obtained relationships are suitable to estimate the transfer of airborne trace elements in the food chain via bush bean.
显示更多 [+] 显示较少 [-]Influences of binding to dissolved organic matter on hydrophobic organic compounds in a multi-contaminant system: Coefficients, mechanisms and ecological risks 全文
2015
Li, Yi-Long | He, Wei | Liu, Wen-Xiu | Kong, Xiang-Zhen | Yang, Bin | Yang, Chen | Xu, Fu-Liu
The complexation flocculation (CF) method was successfully employed to identify binding coefficients (Kdoc) of specific organic contaminants to dissolved organic matter (DOM, often indicated by dissolved organic carbon, DOC) in a multi-contaminant hydrophobic organic contaminant (HOC) system. Kdoc values were obtained for most of the evaluated 33 HOCs, indicating the feasibility and applicability of the CF method in a multi-contaminant system. Significant positive correlations were observed between binding coefficients and octanol–water partition coefficients (Kow) for organic halogen compounds, such as polybrominated diphenyl ethers (PBDEs) (R2 = 0.95, p < 0.05) and organic chlorine pesticides (OCPs) (methoxychlor excluded, R2 = 0.82, p < 0.05). The positive correlations identified between the lgKdoc and lgBCF (bioconcentration factor) for PBDEs and OCPs, as well as the negative correlation observed for polycyclic aromatic hydrocarbons (PAHs), indicated that different binding or partition mechanisms between PAHs and organic halogen compounds exist. These differences further result in discriminative competition partitions of HOCs between DOM and organisms. Assuming that only freely dissolved HOCs are bioconcentrative, the results of DOM-influenced bioconcentration factor (BCFDOM) and DOM-influenced lowest observed effect level (LOELDOM) indicate that the ecological risk of HOCs is decreased by DOM.
显示更多 [+] 显示较少 [-]Integrated analysis of the ecotoxicological and genotoxic effects of the antimicrobial peptide melittin on Daphnia magna and Pseudokirchneriella subcapitata 全文
2015
Galdiero, Emilia | Maselli, Valeria | Falanga, Annarita | Gesuele, Renato | Galdiero, Stefania | Fulgione, Domenico | Guida, Marco
Melittin is a major constituent of the bee venom of Apis mellifera with a broad spectrum of activities. Melittin therapeutical potential is subject to its toxicity and the assessment of ecotoxicity and genotoxicity is of particular interest for therapeutic use. Here we analyzed the biological effects of melittin on two aquatic species, which are representative of two different levels of the aquatic trophic chain: the invertebrate Daphnia magna and the unicellular microalgae Pseudokirchneriella subcapitata. The attention was focused on the determination of: i) ecotoxicity; ii) genotoxicity; iii) antigenotoxicity. Our main finding is that melittin is detrimental to D. magna reproduction and its sub-lethal concentrations create an accumulation dependent on exposition times and a negative effect on DNA. We also observed that melittin significantly delayed time to first eggs. Moreover, results showed that melittin exerted its toxic and genotoxic effects in both species, being a bit more aggressive towards P. subcapitata.
显示更多 [+] 显示较少 [-]The mismatch between bioaccumulation in field and laboratory environments: Interpreting the differences for metals in benthic bivalves 全文
2015
Belzunce-Segarra, Maria J. | Simpson, Stuart L. | Amato, Elvio D. | Spadaro, David A. | Hamilton, Ian L. | Jarolimek, Chad V. | Jolley, Dianne F.
Laboratory-based bioaccumulation and toxicity bioassays are frequently used to predict the ecological risk of contaminated sediments in the field. This study investigates the bioassay conditions most relevant to achieving environmentally relevant field exposures. An identical series of metal-contaminated marine sediments were deployed in the field and laboratory over 31 days. Changes in metal concentrations and partitioning in both sediments and waters were used to interpret differences in metal exposure and bioaccumulation to the benthic bivalve Tellina deltoidalis. Loss of resuspended sediments and deposition of suspended particulate matter from the overlying water resulted in the concentrations of Cu, Pb and Zn (major contaminants) becoming lower in the 1-cm surface layer of field-deployed sediments. Lower exchange rates of overlying waters in the laboratory resulted in higher dissolved metal exposures. The prediction of metal bioaccumulation by the bivalves in field and laboratory was improved by considering the metal partitioning within the surface sediments.
显示更多 [+] 显示较少 [-]Effects of sulfide reduction on adsorption affinities of colloidal graphene oxide nanoparticles for phenanthrene and 1-naphthol 全文
2015
Wang, Fanfan | Wang, Fang | Zhu, Dongqiang | Chen, Wei
The abiotic transformation of nanomaterials in the natural environment can significantly affect their fate, transport, and effects. We observed that the adsorption affinities of graphene oxide nanoparticles (GONPs) for both phenanthrene and 1-naphthol were profoundly enhanced in the presence of sulfide, an environmentally relevant reductant, with doses as low as 0.5 mM Na2S per 10 mg/L GONPs. For phenanthrene adsorption enhancement was predominantly caused by the increased surface hydrophobicity from Na2S treatment. For 1-naphthol, however, adsorption enhancement was caused mainly by the conversion of the epoxy/ether groups on the surface of graphene oxide (GO) to the phenolic hydroxyl and carbonyl groups, which allowed more significant H-bonding between 1-naphthol and GONPs. The findings of this study underline that abiotic transformation of GO not only affects the stability and mobility of GONPs, but also influences the adsorptive interactions between GONPs and environmental contaminants, and consequently, may increase the environmental risks of GONPs.
显示更多 [+] 显示较少 [-]Metabarcoding of benthic eukaryote communities predicts the ecological condition of estuaries 全文
2015
Chariton, Anthony A. | Stephenson, Sarah | Morgan, Matthew J. | Steven, Andrew D.L. | Colloff, Matthew J. | Court, Leon N. | Hardy, Christopher M.
DNA-derived measurements of biological composition have the potential to produce data covering all of life, and provide a tantalizing proposition for researchers and managers. We used metabarcoding to compare benthic eukaryote composition from five estuaries of varying condition. In contrast to traditional studies, we found biotic richness was greatest in the most disturbed estuary, with this being due to the large volume of extraneous material (i.e. run-off from aquaculture, agriculture and other catchment activities) being deposited in the system. In addition, we found strong correlations between composition and a number of environmental variables, including nutrients, pH and turbidity. A wide range of taxa responded to these environmental gradients, providing new insights into their sensitivities to natural and anthropogenic stressors. Metabarcoding has the capacity to bolster current monitoring techniques, enabling the decisions regarding ecological condition to be based on a more holistic view of biodiversity.
显示更多 [+] 显示较少 [-]Occurrence and spatial distribution of organophosphate ester flame retardants and plasticizers in 40 rivers draining into the Bohai Sea, north China 全文
2015
Wang, Runmei | Tang, Jianhui | Xie, Zhiyong | Mi, Wenying | Chen, Yingjun | Wolschke, Hendrik | Tian, Chongguo | Pan, Xiaohui | Luo, Yongming | Ebinghaus, Ralf
Organophosphate esters (OPEs) are alternatives to polybrominated diphenyl ethers, often used as flame-retardants and plasticizers. There are few reports of OPEs in river water. This study focused on the occurrence and spatial distribution of 11 OPE congeners and one synthetic intermediate triphenylphosphine oxide (TPPO) in 40 major rivers entering into the Bohai Sea. Total OPEs ranged from 9.6 to 1549 ng L−1, with an average of 300 ng L−1. Tris(1-chloro-2-propyl) phosphate (TCPP) (4.6–921 ng L−1, mean: 186 ng L−1) and tris(2-choroethyl) phosphate (TCEP) (1.3–268 ng L−1, mean: 80.2 ng L−1) were the most abundant OPEs and their distribution patterns are similar, indicating the same source (r = 0.61, P < 0.05) and the influence of large production and consumption of chlorinated OPEs in the region. Priority should be given to TCPP, PCEP and TPPO due to their high concentrations in the rivers and potential threat to aquatic organisms.
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