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The effects of removing cloudwater and lowering ambient O3 on red spruce grown at high elevations in the southern Appalachians.
1993
Thornton F.C. | McDuffie C. Jr. | Pier P.A. | Wilkinson R.C.
Cadmium availability to wheat in five soil series from the Yonne district, Burgundy, France.
1997
Mench M. | Baize D. | Mocquot B.
Reponses des vegetaux d' une region aride a une pollution atmospherique double: (SO2 + composes fluores).
1994
Ferjani B.A. | Belgacem H. | Makki B.
Pollution of camel milk by heavy metals in Kazakhstan
2009
Konuspayeva G. | Faye B. | Loiseau G. | Diacono E. | Akhmetsadykova S.
Environmental contamination by heavy metals is a common fact in Central Asia. In the present study two sampling procedures were achieved: (i) Sampling of fodder, camel raw milk and shubat (fermented camel milk) in 8 farms closed to pollution sources from the South of Kazakhstan for copper, iron, manganese, zinc, arsenic and lead analysis, (ii) sampling of camel milk in 4 regions of Kazakhstan (63 samples) analyzed for lead, chrome and zinc contamination. In first sampling, camel milk contained 0.07 ± 0.04, 1.48 ± 0.53, 0.08 ± 0.03, 5.16 ± 2.17, <0.1 and 0.025 ± 0.02 ppm respectively for Cu, Fe, Mn, Zn, As and Pb. In shubat (fermented milk) the mean content was 0.163 ± 0.164, 1.57 ± 0.46, 0.088 ± 0.02, 7.217 ± 2.55 and 0.007 ppm respectively. Arsenic was detected in some samples of milk and shubat only. The trace elements concentration increase in shubat compared to milk but lead concentration decreased. No clear correlation was observed with fodder composition. In second sampling, the lead content was on average 250 ± 56 ppb in the camel milk with no significant differences between regions. The maximum value was observed at Atyrau (532 ppb). Zinc content in milk (5.42 ± 0.2 ppm) did not change significantly between regions. In reverse, chrome (59.5 ± 45.4 ppb) was higher in Shymkent region compared to others. These values were discussed according to the proximity of pollution sources. Specially, higher concentrations were experienced in fodder from pastures close to some industrial sites or high traffic road. (Résumé d'auteur)
Afficher plus [+] Moins [-]Does a decade of soil organic fertilization promote copper and zinc bioavailability to an epi-endogeic earthworm?
2023
Laurent, Céline | Bravin, Matthieu | Blanchart, Eric | Crouzet, Olivier | Pelosi, Céline | Lamy, Isabelle
While long-term organic fertilizer (OF) applications tend to decrease copper (Cu) and zinc (Zn) availability in agricultural soils, earthworm bioturbation has been reported to have the opposite effect. Thus, the consequences of OF amendments in earthworm-inhabited soils on Cu and Zn bioavailability to earthworms are still under debate. Here, we assessed the effect of a decade of agronomically realistic OF applications on Cu and Zn availability in earthworm-inhabited soils and the consequences on Cu and Zn bioavailability to earthworms. An epi-endogeic species (Dichogaster saliens) was exposed in microcosms to three field-collected soils that had received either no, mineral, or organic fertilization for a decade. Dissolved organic matter (DOM) properties (i.e., concentration, aromaticity, and binding properties toward Cu), pH, and Cu and Zn availability (i.e., total concentration and free ionic activity) were determined in the solution of the soil containing earthworms. Cu and Zn bioavailability was assessed by measuring the net accumulation (ng) and concentration of Cu and Zn in earthworms (mg kg−1). Despite soil Cu and Zn contamination induced by a decade of OF applications, organic fertilization induced an increase in soil pH and DOM properties that drove the reduction of Cu and Zn availability in earthworm-inhabited soils, while bioturbation had little effect on soil pH, DOM properties, and Cu and Zn availability. Consistently, Cu and Zn bioavailability to earthworms did not increase with OF applications. From an ecotoxicological perspective, our results suggest that agronomically realistic applications of OF for a decade should not pose a risk to earthworms in terms of Cu and Zn net accumulation, but further studies have to be undertaken to understand consequent long-term toxicity after exposure.
Afficher plus [+] Moins [-]Determination of chemical composition of natural waters on the territory of some townships of the central Serbia [Yugoslavia]
1998
Mihajlovic, R. | Plavsic, K. | Mihajlovic, Lj. | Mrdak, C. | Kovacevic, S. | Kanazir, Lj. (Prirodno-matematicki fakultet, Kragujevac (Yugoslavia))
In this paper the results of determination of natural waters from the territory of the township Smederevska Palanka and Rekovac (Serbia, Yugoslavia) are presented. The content of metals in waters was determined by the AAS method and other parameters were determined by spectrophotometric and potentiometric method.
Afficher plus [+] Moins [-]Heavy metals and trace elements content in camel milk and shubat from Kazakhstan
2008
Meldebekova, Aliya | Konuspayeva, Gaukhar | Diacono, Emilie | Faye, Bernard
In Kazakhstan, camel milk is mainly consumed after fermentation process. The fermented camel milk, named shubat, is generally home-made by the traditional process. The changes in mineral composition of camel milk during the fermentation process were rarely studied especially for heavy metals. The present study aimed to assess the change in heavy metals and trace-elements contents during the fermentation process. Samples of milk and shubat were collected in eight farms of Southern Kazakhstan in order to determine copper, iron, manganese, zinc, arsenic and lead. In camel milk mean content of these heavy metals was respectively of 0.065 ± 0.04, 1.478 ± 0.53, 0.084 ± 0.03, 5.163 ± 2.17, <0.1 and 0.025 ± 0.02 ppm. In shubat, the mean content was 0.163 ± 0.164, 1.57 ± 0.46, 0.088 ± 0.02, 7.217 ± 2.55, and 0.007 ppm respectively. Arsenic was detected in some samples of milk and shubat only. A relationship between heavy metals in raw milk and shubat at the farm level was observed. (Résumé d'auteur)
Afficher plus [+] Moins [-]Immobilization of azo-dyes for optical detection of metal ions in water: reaction with Pd(II) [palladium]
2001
Savic, J. | Vasic, V. (Institut za nuklearne nauke "Vinca", Beograd (Yugoslavia). Laboratorija za fizicku hemiju)
The reaction of Pd(II) with 1,8-dihydroxy-2-(pyrazol-5-ylazo)-naphthalen-3,6-disulphonic acid immobilized by physical sorption onto Dowex 1-X8 ion-exchange resin was investigated with the aim to develop the sorption-spectroscopic test method for the detection of low Pd(II) concentrations in water. The resin phase absorption spectra of the reagent and its Pd(II) complex were followed. The immobilized reagent has the spectral characteristics similar to those in the water and forms with Pd(II) 1:1 complex with the absorption maximum at 650 nm. Parameters, such as pH, wavelength and contact time have been optimized for a given amount of the sorbed reagent. The experimental conditions for the linear dependence of absorbance vs. Pd(II) concentration have been determined.
Afficher plus [+] Moins [-]Trace elements and heavy metals statuts in Arabian camel
2008
Faye, Bernard | Seboussi, Rabiha | Askar, Mustapha
In the desert, camel rearing is an important cultural fact. In the present paper, 240 Arabian camels from Emirates were sampled for the determination of trace elements and different heavy metals. The following elements were tested: copper, zinc, iron, aluminium, arsenic, boron, barium, cobalt, chromium, cadmium, manganese, molybdenum, nickel, selenium, strontium and lead. The variation factors included age, sex and physiological status. On the average, the mineral contents were 190.3 µg/100 ml (iron), 60.1 µg/100 ml (copper), 44.0 µg/100 ml (strontium), 22.5 µg/100 ml (arsenic), 20.0 µg/100 ml (zinc), 19.7 µg/100 ml (selenium), 19.3 µg/100 ml (boron) and 14.6 µg/100 ml (barium). Other minerals like aluminium (3.7 µg/100 ml), molybdenum (2.9 µg/100 ml), chromium (2.0 µg/100 ml), nickel (1.8 µg/100 ml), lead (1.5 µg/100 ml), manganese (0.16 µg/100 ml), cobalt (0.08 µg/100 ml) and cadmium (0.07 µg/100 ml) were in very small concentration. Age, sex and physiological effects were assessed for some parameters. According to the lack of references in camel species, it is difficult to link those results to polluting context. But those data could contribute to understand the heavy metal status in camel confronted to pollution. (Résumé d'auteur)
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