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In temperate regions, eolian deposits of different natures are often pedogenically-altered and mixed with underlying sediments. The research reported in this paper identifies for the first time the presence of eolian deposits in soils of central Tuscany and investigates the characteristics and origin. Five relict, polycyclic paleosol profiles were studied. P1 was situated in a natural dust trap, a doline on top of an isolated limestone hill; P2 and P3 were both situated on a limestone plateau, and P4 and P5 on a mid- and foot slope on schist. The profiles were sampled for routine analyses, iron forms, heavy minerals, major and trace elements, and pollen, spores and non-pollen palynomorphs. Undisturbed samples were taken for micromorphological and SEM analyses. Nine soil horizons were sampled for OSL dating. Eolian deposits were dominant or abundant in the first layers of P1, P2 and P3. OSL age determinations of soil horizons deriving from eolian parent material were middle Holocene. Chemical and heavy mineral analyses indicated different possible sources, including bare slopes, alluvial fans and wide channels, coming from the nearby streams that drain the Middle Tuscany ridge and the Mounts of Chianti; marginal contribution of volcanic ashes was only found in P1.The research demonstrated that wind soil erosion accompanied water erosion and colluvial deposition during the middle Holocene in the Elsa River basin. Pollen spectra, in particular, indicated that soil degradation occurred in an environment showing signs of incipient desertification, resulting from an increase of aridity in a land already strongly influenced by humans. Although central Italy is currently considered to be only marginally affected by wind soil erosion, a climate change, which would imply increased arid conditions, could trigger a new cycle of slope denudation, wind erosion and loess deposition.  相似文献   
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A soil-based geochemical survey was carried out in an area of about 350 km2 in northern Kosovo around the Zve?an Pb-Zn smelter. The concentrations of As, Cd, Co, Cr, Cu, Ni, Pb, Sb, Tl, Th, U, Zn were determined in 452 topsoil and 82 subsoil samples. High contents of Pb, Cd, As, Sb, Zn and Cu were found in topsoil over a vast area including the Ibar and Sitnica river valleys. The highest concentrations were usually measured close to the Zve?an smelter. In some zones, the lead contents in surface soils exceeded 5000 mg/kg. Arsenic and antimony levels were usually more than 200 and 50 mg/kg, respectively, while cadmium contents were in the range 5-20 mg/kg. South of the Zve?an area, lead, antimony and cadmium pollution was strong in the densely populated urban area of Kosovska Mitrovica and along the agricultural alluvial plain of the Sitnica River. Depending on the chemical element, the pollution extended 15-22 km north and south of the Zve?an smelter. There was a progressive decrease of heavy element concentrations with increasing distance from the smelting plant. The contents of Pb, Zn, Cu, As, Cd, Sb significantly decreased with soil depth; in fact, the pollution only affected the upper 50 cm of soil. Crops were affected by soil pollution and many food-stuffs exceeded the EU standards. Suggestions for soil remediation are given.  相似文献   
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Multi-matrix environmental monitoring was used to evaluate the influence of a municipal solid waste landfill (Ginestreto, Emilia Romagna, Italy) on the level and distribution of heavy elements in the surrounding environment (air, soil and soil biota). Concentrations of As, Cd, Co, Cr, Cu, Hg, Ni, Pb, Sb, Tl and Zn were measured by inductively coupled plasma-mass spectrometry in transplanted lichens, topsoils and isopods. The highest accumulation levels found for Cd, Cr, Pb, Sb and Zn in lichens transplanted within the Ginestreto landfill. However, similar concentrations of these heavy elements were also found in lichens exposed in monitoring sites influenced by other man-made sources, such as vehicle traffic and truck movements. The fallout of heavy elements emitted by the landfill had low impact on their levels in topsoil: Cd, Cr, Pb, Sb and Zn showed higher contents in topsoil collected close to the landfill and a slight decrease in concentrations with increasing distance from the landfill. There was no variation in heavy element accumulation in isopods in relation to distance from the landfill. The results of this study indicate that the Ginestreto municipal solid waste landfill had limited impact on the environmental distribution of heavy elements, since accumulation and enrichment in lichens and topsoils were only detected close to the landfill, up to about 100 m from its border.  相似文献   
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