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Effects of ozone on crops in north-west Pakistan Texte intégral
2013
Ahmad, Muhammad Nauman | Büker, Patrick | Khalid, Sofia | Van Den Berg, Leon | Shah, Hamid Ullah | Wahid, Abdul | Emberson, Lisa | Power, Sally A. | Ashmore, Mike
Although ozone is well-documented to reduce crop yields in the densely populated Indo-Gangetic Plain, there is little knowledge of its effects in other parts of south Asia. We surveyed crops close to the city of Peshawar, in north-west Pakistan, for visible injury, linking this to passive measurements of ozone concentrations. Foliar injury was found on potato, onion and cotton when mean monthly ozone concentrations exceeded 45 ppb. The symptoms on onion were reproduced in ozone fumigation experiments, which also showed that daytime ozone concentrations of 60 ppb significantly reduce the growth of a major Pakistani onion variety. Aphid infestation on spinach was also reduced at these elevated ozone concentrations. The ozone concentrations measured in April–May in Peshawar, and used in the fumigation experiment, are comparable to those that have been modelled to occur over many parts of south Asia, where ozone may be a significant threat to sensitive crops.
Afficher plus [+] Moins [-]Cadmium and associated metals in soils and sediments of wetlands across the Northern Plains, USA Texte intégral
2013
Jacob, Donna L. | Yellick, Alex H. | Kissoon, La Toya T. | Asgary, Aida | Wijeyaratne, Dimuthu N. | Saini-Eidukat, Bernhardt | Otte, Marinus L.
Cadmium, present locally in naturally high concentrations in the Northern Plains of the United States, is of concern because of its toxicity, carcinogenic properties, and potential for trophic transfer. Reports of natural concentrations in soils are dominated by dryland soils with agricultural land uses, but much less is known about cadmium in wetlands. Four wetland categories – prairie potholes, shallow lakes, riparian wetlands, and river sediments – were sampled comprising more than 300 wetlands across four states, the majority in North Dakota. Cd, Zn, P, and other elements were analyzed by ICP-MS, in addition to pH and organic matter (as loss-on-ignition). The overall cadmium content was similar to the general concentrations in the area's soils, but distinct patterns occurred within categories. Cd in wetland soils is associated with underlying geology and hydrology, but also strongly with concentrations of P and Zn, suggesting a link with agricultural land use surrounding the wetlands.
Afficher plus [+] Moins [-]Characterising metal build-up on urban road surfaces Texte intégral
2013
Egodawatta, Prasanna | Ziyath, Abdul M. | Goonetilleke, Ashantha
Reliable approaches for predicting pollutant build-up are essential for accurate urban stormwater quality modelling. Based on the in-depth investigation of metal build-up on residential road surfaces, this paper presents empirical models for predicting metal loads on these surfaces. The study investigated metals commonly present in the urban environment. Analysis undertaken found that the build-up process for metals primarily originating from anthropogenic (copper and zinc) and geogenic (aluminium, calcium, iron and manganese) sources were different. Chromium and nickel were below detection limits. Lead was primarily associated with geogenic sources, but also exhibited a significant relationship with anthropogenic sources. The empirical prediction models developed were validated using an independent data set and found to have relative prediction errors of 12–50%, which is generally acceptable for complex systems such as urban road surfaces. Also, the predicted values were very close to the observed values and well within 95% prediction interval.
Afficher plus [+] Moins [-]Mycorrhizal colonization affects the elemental distribution in roots of Ni-hyperaccumulator Berkheya coddii Roessler Texte intégral
2013
Orłowska, Elżbieta | Przybyłowicz, Wojciech | Orlowski, Dariusz | Mongwaketsi, Nametso P. | Turnau, Katarzyna | Mesjasz-Przybyłowicz, Jolanta
The effect of arbuscular mycorrhizal fungi (AMF) on the distribution and concentration of elements in roots of Ni-hyperaccumulating plant Berkheya coddii was studied. Micro-PIXE (particle-induced X-ray emission) analysis revealed significant differences between AMF-inoculated and non-inoculated plants as well as between main and lateral roots. The accumulation of P, K, Mn and Zn in the cortical layer of lateral roots of inoculated plants confirmed the important role of AMF in uptake and accumulation of these elements. Higher concentration of P, K, Fe, Ni, Cu and Zn in the vascular stele in roots of AMF-inoculated plants than in the non-inoculated ones indicates more efficient translocation of these elements to the aboveground parts of the plant. These findings indicate the necessity of including the influence of AMF in studies on the uptake of elements by plants and in industrial use of B. coddii for Ni extraction from polluted soils.
Afficher plus [+] Moins [-]Influence of fine process particles enriched with metals and metalloids on Lactuca sativa L. leaf fatty acid composition following air and/or soil-plant field exposure Texte intégral
2013
Schreck, Eva | Laplanche, Christophe | Le Guédard, Marina | Bessoule, Jean-Jacques | Austruy, Annabelle | Xiong, Tiantian | Foucault, Yann | Dumat, Camille
We investigate the effect of both foliar and root uptake of a mixture of metal(loid)s on the fatty acid composition of plant leaves. Our objectives are to determine whether both contamination pathways have a similar effect and whether they interact. Lactuca sativa L. were exposed to fine process particles enriched with metal(loid)s in an industrial area. Data from a first experiment were used to conduct an exploratory statistical analysis which findings were successfully cross-validated by using the data from a second one. Both foliar and root pathways impact plant leaf fatty acid composition and do not interact. Z index (dimensionless quantity), weighted product of fatty acid concentration ratios was built up from the statistical analyses. It provides new insights on the mechanisms involved in metal uptake and phytotoxicity. Plant leaf fatty acid composition is a robust and fruitful approach to detect and understand the effects of metal(loid) contamination on plants.
Afficher plus [+] Moins [-]Estimation of main greenhouse gases emission from household energy consumption in the West Bank, Palestine Texte intégral
2013
Abu-Madi, Maher | Rayyan, Ma'moun Abu
The main GHGs (CO2, NOx, and SO2) have been quantified based on national energy and population statistics. The results show that the contribution of households' energy consumption in the West Bank to global CO2 emission is about 0.016%, while contribution of total energy consumption by all sectors is about 0.041%. The results show that wood is the most polluting energy source in terms of CO2 and NOx emission, while electricity is the most polluting source in terms of SO2. Other sources like diesel, kerosene, and LPG that contribute to the GHGs emission are also quantified. The total amounts of CO2, NOx, and SO2 by households in the West Bank are 4.7 million tonne per year, 3.02 thousand tonne per year, and 2.23 thousand tonne per year respectively. This study presents a set of measures that might help in reducing the level of GHGs emission and protect the environment.
Afficher plus [+] Moins [-]Distillation fraction-specific ecotoxicological evaluation of a paraffin-rich crude oil Texte intégral
2013
Erlacher, Elisabeth | Loibner, Andreas P. | Kendler, Romana | Scherr, Kerstin E.
Crude oil is a complex mixture of petroleum hydrocarbons (PHC) with distinct chemical, physical and toxicological properties relevant for contaminated site risk assessment. Ecotoxicological effects of crude oil distillation fractions on luminescent bacteria (Vibrio fischeri), earthworms (Dendrobaena hortensis) and invertebrates (Heterocypris incongruens) were tested using two spiked soils and their elutriates. Fraction 2 (F2) had an equivalent carbon number (ECN) range of >10 to 16, and F3 from >16 to 39. F2 showed a substantially higher ecotoxicological effect than F3 for Vibrio and Dendrobaena. In contrast, severe inhibition of Heterocypris by the poorly soluble F3 is attributed to mechanical organ blockage. Immediate sequestration of PHC to the organic matter-rich soil effected reduced toxicity for all organisms. This study indicates that a more differentiated consideration (i) of PHC mixtures based on ECN range and (ii) of model soil properties employed for ecotoxicity testing should be included into PHC-contaminated site risk assessment.
Afficher plus [+] Moins [-]Reclamation of copper-contaminated soil using EDTA or citric acid coupled with dissolved organic matter solution extracted from distillery sludge Texte intégral
2013
Liu, Zhengzhong | Lin, Ying-Chen
Soil washing using a strong chelating agent is a common practice for restoring contaminated soils, but significant soil fertility degradation and high operation costs are the major disadvantages. Washing soil with a dissolved organic matter (DOM) solution has been identified as a method that can moderate the loss of nutrients in the soil and enhance metal removal. The DOM solutions were extracted from waste sludge obtained from a local whisky distillery. Single chelating washing and chelate-DOM washing were carried out using ethylenediaminetetraacetic acid (EDTA), citric acid, and DOM solutions to remediate highly Cu-contaminated soil. Two-phase washing using 0.34 M citric acid and then 1500 mg L−1 DOM solution (pH 8.5) was found to be most favorable for the soil. With this treatment, 91% Cu was removed from the topsoil; the organic matter, cation exchange capacity, plant-available nitrogen, and available phosphate content increased by 28.1%, 103%, 17.7%, and 422%, respectively.
Afficher plus [+] Moins [-]Adverse effects induced by ecgonine methyl ester to the zebra mussel: A comparison with the benzoylecgonine Texte intégral
2013
Parolini, Marco | Binelli, Andrea
Cocaine and its metabolites are the prevalent psychotropic substances in aquatic environment. However, to date the knowledge on their adverse effects to non-target organisms is inadequate. The aims of this study were to investigate sub-lethal effects induced by the ecgonine methyl ester (EME) to the freshwater bivalve Dreissena polymorpha and to compare its toxicity to that by benzoylecgonine (BE), the other main cocaine metabolite. EME sub-lethal effects were investigated by 14 days in-vivo exposures and a multi-biomarker approach. Slight variations in biomarker responses were found at 0.15 μg/L treatment. 0.5 μg/L EME treatment induced destabilization of lysosome membranes, an overall inactivation of defense enzymes, increases in lipid peroxidation, protein carbonylation and DNA fragmentation, but no variations in fixed genetic damage. The use of a biomarker response index (BRI) showed that at 0.5 μg/L both cocaine metabolites had the same toxicity to zebra mussels specimens.
Afficher plus [+] Moins [-]Breeding performance of blue tits (Cyanistes cæruleus ultramarinus) in relation to lead pollution and nest failure rates in rural, intermediate, and urban sites in Algeria Texte intégral
2013
Brahmia, Zahra | Scheifler, Renaud | Crini, Nadia | Maas, Samuel | Giraudoux, Patrick | Benyacoub, Slim
The breeding parameters and the egg and nestling morphology of Cyanistes caeruleus populations from rural, intermediate, and urban sites in Algeria and the relationships of those variables with lead contamination were studied during three consecutive years. Breeding success was explained only by predation and vandalism rates. Predation was higher in the rural area, whereas vandalism was higher in the urban site. The other measured breeding parameters and egg characteristics were relatively insensitive to study site. The morphology of urban nestlings exhibited a trend toward smaller body size and mass compared to individuals from intermediate and rural sites. Although lead concentrations were higher in the tissues of urban birds than in intermediate and rural individuals, we did not detect a clear influence of this variable on nestling morphology. We conclude that urbanization influenced blue tit breeding parameters through predation and vandalism and nestling morphology through mechanisms other than lead pollution.
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