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721.
Yasundo?KurataEmail author Yusaku?Ono Yoshiro?Ono 《Journal of Material Cycles and Waste Management》2008,10(2):144-152
The concentrations of 41 phenols in leachates from 38 municipal solid waste (MSW) landfill sites in Japan were measured. The
main phenols detected in leachates were phenol, three cresols, 4-tert-butylphenol, 4-tertoctylphenol, 4-nonylphenol, bisphenol
A, and some chlorophenols. The concentration levels of phenols were affected by the pH values of the leachates and the different
types of landfill waste. The origins of phenol and p-cresol were considered to be incineration residues, and the major origin of 4-tert-butylphenol, bisphenol A, and 2,4,6-trichlorophenol
was considered to be solidified fly ash. In contrast, the major origins of 4-tert-octylphenol and 4-nonylphenol were considered
to be incombustibles. The discharge of leachates to the environment around MSW landfill sites without water treatment facilities
can cause environmental pollution by phenols. In particular, the disposal of incineration residues including solidified fly
ash and the codisposal of solidified fly ash and incombustibles might raise the possibility of environmental pollution. Moreover,
the discharge of leachates at pH values of 9.8 or more could pollute the water environment with phenol. However, phenol, 4-nonylphenol,
and bisphenol A can be removed to below the con centration levels that impact the environment around landfill sites by a series
of conventional water treatment processes. 相似文献
722.
Jörg Luster Manoj Menon Sandra Hermle Rainer Schulin Madeleine S. Günthardt-Goerg Bernd Nowack 《Water, Air, & Soil Pollution: Focus》2008,8(2):163-176
Soil translocation for recultivation of soil removed from construction sites and for the preparation of refilled lysimeters
inevitably involves disturbance of soil structure, and, if intermediate storage is included, also drying and rewetting of
the soil. We report on an experiment with model forest ecosystems, where uncontaminated forest subsoils were covered with
non-contaminated or freshly heavy metal (mainly Zn and Cu) contaminated topsoil in large lysimeters. Monitoring of the chemical
composition of the drainage water revealed two distinct soil conditioning phases. During an initial phase of about a year
strongly elevated nitrate and sulfate concentrations occurred that were attributed to a mineralisation flush caused by the
increased accessability of mineralisable nitrogen and sulfur in destroyed aggregates. These effects were significantly larger
in lysimeters with calcareous subsoil than in those with acidic subsoil. The second phase was characterised by a gradual decrease
in dissolved organic carbon and sulfate concentrations, in particular in the acidic subsoil. This decrease may be attributed
to the depletion of pools made accessible during aggregate destruction or the formation of new aggregates. These chemical
changes had only little effects on the concentrations of copper and zinc in the drainage water. Based on our results, it can
be concluded that large refilled lysimeters can be used for many purposes without risk of compromised results, if a conditioning
phase of about 1 year with sufficiently moist soil conditions is respected. Nevertheless, gradual changes in soil chemical
characteristics still occur after this initial phase. Implications for the recultivation of sites using relocated soils are
discussed. 相似文献
723.
A. A. Olajire E. T. Ayodele F. E. Imeokparia 《Environmental monitoring and assessment》1999,57(2):183-194
Samples of compost-amended soil from waste dumping sites in Lagos Metropolis were extracted with dichloromethane (3 × 20 cm3) and the extract was evaporated at 35 °>C. The residue was extracted with 2,2,4-trimethylpentane, and portions of the solution were applied to a column containing silica gel from which aliphatic and aromatic hydrocarbons were eluted with n-hexane and toluene respectively. Analysis of the n-hexane fraction using gas chromatography showed the presence of a mixture of aliphatic hydrocarbons, ranging from C9 to C25, while ultraviolet analysis of the toluene fraction suggested 1,2-benzanthracene; 2,3-benzphenanthrene, chrysene and pyrene as polyaromatic compounds present in samples analyzed. The crude extracts were highly coloured and viscous. Total extractable organic residues in the 2,2,4-trimethylpentane extracts ranged from 36 to 89 mg g-1 of soil. 相似文献
724.
Stefano Loppi Stergios Arg. Pirintsos Vincenzo De Dominicis 《Environmental monitoring and assessment》1999,58(2):121-131
Total concentrations of Al, Ba, Cd, Co, Cr, Cu, Fe, Mn, Mo, Pb, Sr, Ti, V and Zn in the epiphytic lichen Parmelia sulcata and superficial soils from 60 remote sampling sites in Tuscany (central Italy) were determined to evaluate the contribution of soil to the elemental composition of the lichen. The results showed that in the Mediterranean environment, the trace element content of unwashed lichen samples is greatly affected by soil contamination. However, despite the strong correlations between the concentrations of lithogene elements such as Al, Fe and Ti in P. sulcata, lichen levels of these elements were not at all linearly correlated with their concentrations in the soil, suggesting that dust contamination is highly variable and probably dependent on local site characteristics. All methods evaluated to minimize soil contamination indicated Cu, Pb and Zn as elements of atmospheric origin. However, while levels of Pb were similar to those reported for background areas, moderate pollution by Cu and Zn, probably from fertilizers used in agriculture, was revealed. For elements such as Cd and Mo, identified as atmophile, some uncertainty exists due to the fact that they are essential for lichen metabolism and accumulate intracellularly in lichens; they may therefore occur in soluble form in the lichen thallus. 相似文献
725.
Many environmental surveys require the implementation of estimation techniques to determine the spatial distribution of the variable being investigated. Traditional methods of interpolation and estimation, for example, inverse distance squared and triangulation often ignore features of the data set such as anisotropy which may have a significant impact on the quality of the estimates produced. Geostatistical techniques may offer an improved method of estimation by modelling the spatial continuity of the variable using semi-variogram analysis. The theoretical model fitted to the semi-variogram is then used in the assignation of weighting factors to the samples surrounding the location to be estimated. This paper outlines the results of a comparison between three common estimation methods, polygonal, triangulation and inverse distance squared and a geostatistical method, in the estimation of soil radionuclide activities. The geostatistical estimation method known as kriging performed best over a range of parameters used to test the performance of the methods. Kriging exhibited the best correlation between actual and estimated values, the narrowest error distribution and the lowest overall estimation error. Polygonal estimation was best at reproducing the data set distribution. Conditional bias was evident in all the methods, low values being over-estimated and high values being under-estimated. 相似文献
726.
采集并分析全场不同母质形成的有代表性的土壤样本142个.研究结果表明,各类土壤全B、Mo、Zn和Mn含量的平均值均低于全国平均值,全量Cu平均值高于全国平均值.有效B、Mo、Zn和Mn含量的平均值均低于临界值,有效Cu的平均值稍高于临界值;但66.7%的土样有效Cu含量低于临界值.硼、钼、锌和锰严重缺乏,铜多数缺乏.全场各类土壤的微量元素含量差异较大,各类土壤微量元素的垂直和水平分布特征不尽相同,尤其是垂直分布差异明显.从土壤微量元素的全量与母质的关系来看,以玄武岩、紫色砂页岩母质形成的土壤全量较高,砂砾岩母质形成的土壤全量中等,砂页岩和冲积物母质形成的土壤全量较低. 相似文献
727.
728.
溶液中Al3 、Al-F和有机络合态铝(Al-OM的浓度随pH降低而增加,Al3 在总单核铝中所占比例随pH的降低而增加,而Al-F络合物呈相反的变化趋势.土壤中铝的溶解度与土壤中铝氧化物的结晶形态有关,处于较高纬度地区的土壤,由于铝氧化物的结晶形态较差,在相同pH下,其铝的溶解度较大.土壤溶液中有机络合态铝的浓度随温度升高而增加,在pH不变的情况下,土壤中无机铝的溶解量随温度降低而增加.随水土比增加,土壤溶液中Al3 、Al-F络合物和Al-OM浓度减小,但按每kg土计算的铝溶解量随水土比的增加而增加. 相似文献
729.
730.