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Cd-tolerant Suillus luteus: A fungal insurance for pines exposed to Cd Полный текст
2009
Krznaric, Erik | Verbruggen, Nathalie | Wevers, Jan H.L. | Carleer, Robert | Vangronsveld, Jaco | Colpaert, Jan V.
Soil metal pollution can trigger evolutionary adaptation in soil-borne organisms. An in vitro screening test showed cadmium adaptation in populations of Suillus luteus (L.: Fr.) Roussel, an ectomycorrhizal fungus of pine trees. Cadmium stress was subsequently investigated in Scots pine (Pinus sylvestris L.) seedlings inoculated with a Cd-tolerant S. luteus, isolated from a heavy metal contaminated site, and compared to plants inoculated with a Cd-sensitive isolate from a non-polluted area. A dose-response experiment with mycorrhizal pines showed better plant protection by a Cd-adapted fungus: more fungal biomass and a higher nutrient uptake at high Cd exposure. In addition, less Cd was transferred to aboveground plant parts. Because of the key role of the ectomycorrhizal symbiosis for tree fitness, the evolution of Cd tolerance in an ectomycorrhizal partner such as S. luteus can be of major importance for the establishment of pine forests on Cd-contaminated soils. The evolutionary adaptation for higher Cd tolerance in Suillus luteus, an ectomycorrhizal fungus, is of major importance for the amelioration of Cd toxicity in pine trees exposed to high Cd concentrations.
Показать больше [+] Меньше [-]Long-term pollution by chlordecone of tropical volcanic soils in the French West Indies: A simple leaching model accounts for current residue Полный текст
2009
Cabidoche, Y.M. | Achard, R. | Cattan, P. | Clermont-Dauphin, C. | Massat, F. | Sansoulet, J.
Long-term pollution by chlordecone of tropical volcanic soils in the French West Indies: A simple leaching model accounts for current residue Полный текст
2009
Cabidoche, Y.M. | Achard, R. | Cattan, P. | Clermont-Dauphin, C. | Massat, F. | Sansoulet, J.
Chlordecone was applied between 1972 and 1993 in banana fields of the French West Indies. This resulted in long-term pollution of soils and contamination of waters, aquatic biota, and crops. To assess pollution level and duration according to soil type, WISORCH, a leaching model based on first-order desorption kinetics, was developed and run. Its input parameters are soil organic carbon content (SOC) and SOC/water partitioning coefficient (Koc). It accounts for current chlordecone soil contents and drainage water concentrations. The model was valid for andosol, which indicates that neither physico-chemical nor microbial degradation occurred. Dilution by previous deep tillages makes soil scrapping unrealistic. Lixiviation appeared the main way to reduce pollution. Besides the SOC and rainfall increases, Koc increased from nitisol to ferralsol and then andosol while lixiviation efficiency decreased. Consequently, pollution is bound to last for several decades for nitisol, centuries for ferralsol, and half a millennium for andosol. Soil and water contamination by chlordecone will persist for several centuries in the French West Indies, because the only decontamination is through leaching by drainage water.
Показать больше [+] Меньше [-]Long-term pollution by chlordecone of tropical volcanic soils in the French West Indies: A simple leaching model accounts for current residue Полный текст
2009
Cabidoche, Yves-Marie | Achard, Raphaël | Cattan, Philippe | Clermont-Dauphin, Claridge | Massat, Félix | Sansoulet, Julie
Chlordecone was applied between 1972 and 1993 in banana fields of the French West Indies. This resulted in long-term pollution of soils and contamination of waters, aquatic biota, and crops. To assess pollution level and duration according to soil type, WISORCH, a leaching model based on first-order desorption kinetics, was developed and run. Its input parameters are soil organic carbon content (SOC) and SOC/water partitioning coefficient (Koc). It accounts for current chlordecone soil contents and drainage water concentrations. The model was valid for andosol, which indicates that neither physicochemical nor microbial degradation occurred. Dilution by previous deep tillages makes soil scrapping unrealistic.Lixiviation appeared the main way to reduce pollution. Besides the SOC and rainfall increases, Koc increased from nitisol to ferralsol and then andosol while lixiviation efficiency decreased. Consequently, pollution is bound to last for several decades for nitisol, centuries for ferralsol, and half a millennium for andosol.
Показать больше [+] Меньше [-]Long-term pollution by chlordecone of tropical volcanic soils in the French West Indies: A simple leaching model accounts for current residue Полный текст
2009
Cabidoche , Yves-Marie (INRA , Petit-Bourg (France). UR 0135 Unité de Recherche AgroPédoClimatique de la zone caraïbe) | Achard , Raphaël (Centre de Coopération Internationale en Recherche Agronomique pour le DéveloppementPôle de Recherche Agro-Environnementale de la Martinique, Le LamentinLe Lamentin(France). UPR Systemes Bananes et Ananas) | Cattan , Philippe (Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Capesterre-Belle-Eau(France). UPR Systèmes Bananes et Ananas (Guadeloupe)) | Clermont-Dauphin , Claridge (INRA , Petit-Bourg (France). UR 0135 Unité de Recherche AgroPédoClimatique de la zone caraïbe) | Massat , Félix (Laboratoire Départemental d’Analyses de la Drôme, Valence(France).) | Sansoulet , Julie (INRA , Petit-Bourg (France). UR 0135 Unité de Recherche AgroPédoClimatique de la zone caraïbe)
Chlordecone was applied between 1972 and 1993 in banana fields of the French West Indies. This resulted in long-term pollution of soils and contamination of waters, aquatic biota, and crops. To assess pollution level and duration according to soil type, WISORCH, a leaching model based on first-order desorption kinetics, was developed and run. Its input parameters are soil organic carbon content (SOC) and SOC/water partitioning coefficient (Koc). It accounts for current chlordecone soil contents and drainage water concentrations. The model was valid for andosol, which indicates that neither physicochemical nor microbial degradation occurred. Dilution by previous deep tillages makes soil scrapping unrealistic.Lixiviation appeared the main way to reduce pollution. Besides the SOC and rainfall increases, Koc increased from nitisol to ferralsol and then andosol while lixiviation efficiency decreased. Consequently, pollution is bound to last for several decades for nitisol, centuries for ferralsol, and half a millennium for andosol.
Показать больше [+] Меньше [-]Source identification of copper, lead, nickel, and zinc loading in wastewater reclamation plant influents from corrosion of brass in plumbing fixtures Полный текст
2009
Kimbrough, David Eugene
A natural experiment indicated that a link between the presence and concentration of four elements, copper, lead, nickel, and zinc in the influent to two wastewater reclamation plants to the presence and concentrations of the same four elements in the tap water of residential properties. There were 36 populations of results that were assessed for the normality of their distribution, the difference in their median concentrations, the similarity in the ratios of their median concentrations, and the correlations of the concentrations. The results of this study suggest that brass corrosion is the major source of these four elements in the water reclamation plants influent and that there are two distinct populations of brass sources, those in the early stages of dezincification where the release of the non-copper elements is dominant and those in the later stages where the release of copper dominates and the type of brass that is corroding. Statistical analysis of residential tap waters and water reclamation plant influent showed that metals found in both came from brass corrosion.
Показать больше [+] Меньше [-]Naturally-assisted metal phytoextraction by Brassica carinata: Role of root exudates Полный текст
2009
Quartacci, Mike F. | Irtelli, Barbara | Gonnelli, Cristina | Gabbrielli, Roberto | Navari-Izzo, Flavia
Due to relatively high chelant dosages and potential environmental risks it is necessary to explore different approaches in the remediation of metal-contaminated soils. The present study focussed on the removal of metals (As, Cd, Cu, Pb and Zn) from a multiple metal-contaminated soil by growing Brassica carinata plants in succession to spontaneous metallicolous populations of Pinus pinaster, Plantago lanceolata and Silene paradoxa. The results showed that the growth of the metallicolous populations increased the extractable metal levels in the soil, which resulted in a higher accumulation of metals in the above-ground parts of B. carinata. Root exudates of the three metallicolous species were analysed to elucidate their possible role in the enhanced metal availability. The presence of metals stimulated the exudation of organic and phenolic acids as well as flavonoids. It was suggested that root exudates played an important role in solubilising metals in soil and in favouring their uptake by roots.
Показать больше [+] Меньше [-]Uptake kinetics of metals by the earthworm Eisenia fetida exposed to field-contaminated soils Полный текст
2009
Nahmani, Johanne | Hodson, Mark E. | Devin, Simon | Vijver, Martina G.
Uptake kinetics of metals by the earthworm Eisenia fetida exposed to field-contaminated soils Полный текст
2009
Nahmani, Johanne | Hodson, Mark E. | Devin, Simon | Vijver, Martina G.
It is well known that earthworms can accumulate metals. However, most accumulation studies focus on Cd-, Cu-, Pb- or Zn-amended soils, additionally few studies consider accumulation kinetics. Here we model the accumulation kinetics of 18 elements by Eisenia fetida, exposed to 8 metal-contaminated and 2 uncontaminated soils. Tissue metal concentrationwas determined after 3, 7, 14, 21, 28 and 42 days. Metal elimination rate was important in determining time to reach steady-state tissue metal concentration. Uptake flux to elimination rate ratios showed less variation and lower values for essential than for non-essential metals. In theory kinetic rate constants are dependent only on species and metal. Therefore it should be possible to predict steady-state tissue metal concentrations on the basis of very few measurements using the rate constants. However, our experiments show that it is difficult to extrapolate the accumulation kinetic constants derived using one soil to another.
Показать больше [+] Меньше [-]Uptake kinetics of metals by the earthworm Eisenia fetida exposed to field-contaminated soils Полный текст
2009
Nahmani, J. | Hodson, M. E. | Devin, S. | Vijver, M. G.
It is well known that earthworms can accumulate metals. However, most accumulation studies focus on Cd-, Cu-, Pb- or Zn-amended soils, additionally few studies consider accumulation kinetics. Here we model the accumulation kinetics of 18 elements by Eisenia fetida, exposed to 8 metal-contaminated and 2 uncontaminated soils. Tissue metal concentration was determined after 3, 7,14, 21, 28 and 42 days. Metal elimination rate was important in determining time to reach steady-state tissue metal concentration. Uptake flux to elimination rate ratios showed less variation and lower values for essential than for non-essential metals. In theory kinetic rate constants are dependent only on species and metal. Therefore it should be possible to predict steady-state tissue metal concentrations on the basis of very few measurements using the rate constants. However, our experiments show that it is difficult to extrapolate the accumulation kinetic constants derived using one soil to another. (C) 2009 Elsevier Ltd. All rights reserved.
Показать больше [+] Меньше [-]Detecting atmospheric pollution in surface soils using magnetic measurements: A reappraisal using an England and Wales database Полный текст
2009
Blundell, A. | Hannam, J.A. | Dearing, J.A. | Boyle, J.F.
Industrial activity such as burning of fossil fuels produces magnetically enhanced particulates. These particulates consist of coarse-grained multidomain and stable single domain magnetic minerals. Two threshold values of low field magnetic susceptibility (XLF) and frequency dependent susceptibility percentage (XFD%) discriminate ferrimagnetic minerals of these sizes and can act as a tracer of magnetic pollution. Application of the thresholds to a magnetic topsoil data set (n = 5656 across England and Wales) revealed 637 samples potentially dominated by pollution particulates. The magnetic parameters of these samples display a negative correlation with distance to urban areas and positive correlations with metals associated with anthropogenic activity (Cu, Pb, and Zn). Results of experimentation with threshold values and modelling of magnetic anomalies suggest that regional factors such as geology and potential for pedogenic secondary magnetic enhancement should be considered when setting threshold values.
Показать больше [+] Меньше [-]Abiotic oxidation of 17β-estradiol by soil manganese oxides Полный текст
2009
Sheng, G Daniel | Xu, Chao | Xu, Lei | Qiu, Yuping | Zhou, Hongyi
The degradation of 17b-estradiol (E2) in sterile soil and Mn-free soil slurries was determined. In 0.075 g ml⁻¹ soil slurry, E2 with an initial concentration of 0.0267 mmol g⁻¹ was rapidly degraded and near equimolar estrone (E1) accumulated. A mass balance involving E2 and E1 existed throughout the reaction. The E2 degradation was thus an oxidation process and E1 was the only product. The concurrent release of Mn(II) during E2 oxidation and a lack of E2 oxidation in Mn-free soil slurry together demonstrated that soil manganese oxides were responsible for E2 oxidation. The degree of E2 oxidation was higher at high pH than at low pH, consistent with the fact that the reaction released protons. This study suggests that manganese oxides may be used as soil amendments to effectively oxidize E2 to less potent E1 in soil.
Показать больше [+] Меньше [-]Historical record of black carbon in urban soils and its environmental implications Полный текст
2009
He, Yue | Zhang, Gan-Lin
Energy use in urbanization has fundamentally changed the pattern and fluxes of carbon cycling, which has global and local environmental impacts. Here we have investigated organic carbon (OC) and black carbon (BC) in six soil profiles from two contrast zones in an ancient city (Nanjing) in China. BC in soils was widely variable, from 0.22 to 32.19 g kg⁻¹. Its average concentration in an ancient residential area (Zone 1) was, 0.91 g kg⁻¹, whereas in Zone 2, an industrial and commercial area, the figure was 8.62 g kg⁻¹. The ratio of BC/OC ranged from 0.06 to 1.29 in soil profiles, with an average of 0.29. The vertical distribution of BC in soil is suggested to reflect the history of BC formation from burning of biomass and/or fossil fuel. BC in the surface layer of soils was mainly from traffic emission (especially from diesel vehicles). In contrast, in cultural layers BC was formed from historical coal use. The contents of BC and the ratio of BC/OC may reflect different human activities and pollution sources in the contrasting urban zones. In addition, the significant correlation of heavy metals (Cu, Pb, and Zn) with BC contents in some culture layers suggests the sorption of the metals by BC or their coexistence resulted from the coal-involved smelting. Soil black carbon can reflect the pollution history of a city during urbanization.
Показать больше [+] Меньше [-]Origin of polluted air masses in the Alps. An overview and first results for MONARPOP Полный текст
2009
Kaiser, August
The contribution of ZAMG to MONAROP consists of special weather forecasts to control the SOCs sampling procedure and of the analysis of the specific transport processes for SOCs, which is still in progress. In this paper, air pollutant transport into the Alps is demonstrated by examples of inorganic pollutants: Measurements of NOx and ozone provide evidence for air pollutant transport by local wind systems (valley and slope winds), especially at low elevated sites of the Alps. In addition, trajectory analyses for the high elevation sites demonstrate the importance of large scale synoptic air pollutant transport. The effects of these transport processes with different spatial and temporal scales are governed by the physical and chemical properties of the particular pollutant. First results for the high alpine MONARPOP stations show that air masses from east Europe influence mostly Sonnblick (Austria), whereas the influence of the Po basin is strongest at Weissfluhjoch (Switzerland). Effects of meteorological transport processes on air pollution in the Alps are demonstrated by examples of inorganic pollutants and first conclusions for SOCs are drawn.
Показать больше [+] Меньше [-]Iron-rich dune grasslands: Relations between soil organic matter and sorption of Fe and P Полный текст
2009
Kooijman, A.M. | Lubbers, I. | Til, M van
Effects of high atmospheric nitrogen-deposition partly depend on availability of phosphate. Lime-poor, but iron-rich dune grasslands are supposedly protected from grass-encroachment, due to P-fixation in iron phosphate. However, in iron-rich Dutch hinterdunes, dunes have low, but dry former beach plains high grass-encroachment. To test whether these zones differ in nutrient availability, and whether this changed with duration of grass-encroachment, we measured net N-mineralization, microbial characteristics and different fractions of P and Fe from pioneer and shortgrass to tallgrass stages approximately 10, 20 and >25 years old. N-mineralization did not differ between zones, but increased in older tallgrass stages in the organic layer. P-availability was significantly lower in the low grass-encroachment zone, with SOM values below 3% and mineral Fe above 40% allowing for P-fixation in iron phosphates. In the high grass-encroachment zone, however, P-availability increased, because SOM increased and Fe became incorporated in organic matter complexes, with more reversible P-sorption. Iron-rich dune grasslands may be protected from high N-deposition and grass-encroachment only when SOM is low, because only then P-fixation in iron phosphates occurs.
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