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Incinerated Sewage Sludge Products as Amendments for Agricultural Soils: Leaching and Plant Uptake of Trace Elements
2006
(Aruṇakiri)
Preliminary leaching column and greenhouse plant uptake studies were conducted in two soils with contrasting characteristics amended with varying rates (0 to 148.3 Mg ha-1) of incinerated sewage sludge (ISS) and weathered sewage sludge (WISS) to estimate the leaching losses of trace elements from the soils amended with incinerated sewage sludge by products and to evaluate the uptake and accumulation of these elements in various parts of Sorghum vulgaris var. sudanense Hitche. (“Sorgrass''), a Sorghum-Sudan grass hybrid. Results of this study indicated that leaching of Cr, Cd, Zn, Cu, Ni, Fe and Mn from soils amended with ISS and WISS increased with increasing rates of amendment. Results of the leaching column study further revealed greater leaching losses from coarse-textured soil compared to medium-textured soil and also from ISS amended soils than with WISS amended soils. Results further suggested that the type of element and the interaction between the element and soil properties affected the leachability of various trace elements. The uptake study indicated uptake and accumulation of trace elements by plant parts increased with increasing rates of amendments. Greater plant uptake and accumulation of trace elements were observed in plant parts grown in soils amended with ISS compared to that of WISS. Results also indicated a greater accumulation of trace elements in below ground part of the plants (roots) compared to that was observed in above ground parts (shoots). Limited data obtained from this one season preliminary studies demonstrated that incinerated sewage sludge products from wastewater treatment plants could be used as soil amendments at low application (no more than 24.7 Mg ha-1) for optimum plant growth, and dry matter yield without resulting in substantial accumulation of metals in plant parts at concentrations above the recommended critical limits and without causing significant leaching losses of various trace elements. It is imperative that long-term field studies are necessary to evaluate the long-term impact of using these new products in leaching and accumulation of various trace elements in plants and soils.
Afficher plus [+] Moins [-]Speciation Of Pb In Industrially Polluted Soils
2006
Jensen, P.E. | Ottosen, L.M. | Pedersen, A.J.
This study was aimed at elucidating the importance of original Pb-speciation versus soil-characteristics to mobility and distribution of Pb in industrially polluted soils. Ten industrially polluted Danish surface soils were characterized and Pb speciation was evaluated through SEM-EDX studies, examination of pH-dependent desorption, distribution in grain-size fractions and sequential extraction. Our results show that the first factors determining the speciation of Pb in soil are: (1) the stability of the original speciation and (2) the contamination level, while soil characteristics are of secondary importance. In nine of ten soils Pb was concentrated strongly in the soil fines (< 0.063 mm). In all soils, particles with a highly concentrated Pb-content were observed during SEM-EDX. In eight of the soils, the particles contained various Pb-species with aluminum/iron, phosphate, sulfate and various metals (in solder and other alloys) as important associates. In the one soil, where Pb was not concentrated in the soil fines, Pb was precipitated solely as PbCrO₄, while pure (metallic) Pb was repeatedly observed in the last soil. Pb was bound strongly to the soils with > 50% extracted in step III (oxidizing) and IV (residual) of sequential extraction for all soils but one. A significant amount of exchangeable Pb existed only in severely contaminated soils, where the bonding capacity of organic matter and oxides was exceeded. Among soil constituents, Pb was observed to adsorb preferentially to feldspars and organic matter while presence of phosphate increased the strength of the Pb-bonding in phosphate-rich soils.
Afficher plus [+] Moins [-]Determination of heavy metals in sediments of the Skadar lake [Montenegro]
2006
Duborija, A. (Institut za tehnicka istrazivanja, Podgorica (Montenegro)), E-mail: acoduborija@cg.yu | Stanisavljevic, M. (Univerzitet u Nisu, Nis (Serbia). Fakultet zastite na radu)
The objective of this paper is establishing eco-chemical characterization of the Skadar lake (i.e. Lake Scutari) system by investigation of heavy metal content and distribution in the lake sediments. Factors that influence heavy metal concentrations in sediments are allochthonous (natural and human effects) and autochthonous (natural processes of settling and sorption) as well as transformation of settled substances in sediments. Sediments samples were taken from 15 sites and analysed for copper (Cu), zinc (Zn), cadmium (Cd) and lead (Pb).
Afficher plus [+] Moins [-]Comparative review of physico-chemical analysis of river Moravica [Serbia] water and heavy metals presence in slime and herb Mentha aquatica
2006
Milenovic, V. | Janjic, L. (Univerzitet u Nisu, Nis (Serbia). Fakultet zastite na radu)
In the course of implementation of project Ecological Significance Evaluation of River Moravica Basin with Pollutants Identification, supported by REC and DRP, chemical and physical water analysis were done, as well as slime analysis. Heavy metals presence in water, herb Mentha aquatica and slime was analysed at six relevant locations downstream river Moravica. Heavy metals test results in slime and herb Mentha aquatica points out the presence of Zn, Cu, Fe, Mn, with heavy metals concentration rise from spring to mouth of river Moravica to river Juzna Morava. Chemical and physical analysis of water content, and detection of heavy metals presence in herb Mentha aquatica - as bioindicator and in slime, shows on water contamination with heavy metals as the inflow result of waste waters from numerous polluters.
Afficher plus [+] Moins [-]Quality of the spring waters with regard to the level of lead, cadmium and zinc on territory of the Northern Kosovo and Metohija [Serbia]
2006
Babincev, Lj.M. (Fakultet tehnickih nauka, Kosovska Mitrovica (Serbia))
This is the presentation of the content of heavy metals (Pb, Cd and Zn) originating from the several representative locations of the natural water springs in the Northern Kosovo and Metohija . For the determination of presence and content of Pb, Cd and Zn in these spring waters the Potentiometric stripping analysis (PSA) method was used as a high-sensitive and selective electroanalytical technique.
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