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61.
In August 2002 extreme floods affected Bohemia a part of the Czech Republic, along Vltava and Labe rivers. After the flood had culminated, soil samples of arable and meadow soil (flooded and control-non-flooded) have been collected in the surroundings of the cities of ?eské Budějovice (CB, South Bohemia, the Vltava river, the upper flood stream) and Ústí nad Labem (UL, the Labe river, the lower flood stream). Different parameters of arable soils have been affected more significantly than those of meadow soils. Soil texture e.g. has been shifted from sandy loam to loam (CB) and clay loam (UL). Organic carbon, total phosphorus and nitrogen contents have been increased as well as the content of some hazardous elements such as arsenic. A shift of soil pH from 6.1 to 4.8 has been noticed in CB and an opposite one from 5.1 to 7.1 was measured in UL. Available phosphorus decreased in CB by 56% while a four-fold increase was measured in UL. Chlorinated organic pesticides level was significantly reduced, but that of polycyclic aromatic hydrocarbons (PAH) increased up to the maximum values of legal limits. The UL arable soil also became heavily contaminated by PAH. The CB arable soil demonstrated high microbial activity, while UL arable soil suffered under stress conditions in this respect. The flooded meadow soils became covered with a layer of drifted soil sediment, which retained enhanced content of the PAH's different hazardous elements, and, in addition, the soil aeration was reduced.  相似文献   
62.
This paper presents transformations of saturated hydrocarbons of petroleum type pollutants during ex situ bioremediation of soil on the pilot heap (halde), during a period of 6 months, within the grounds of Petroleum Refinery Pan?evo (Serbia). Samples for analysis were taken in time intervals of 2 weeks (P1–P12 samples). Organic substance was extracted by Soxhlet’s method and quantified. Isoprenoid aliphatics, in particular pristane and phytane, and polycyclic aliphatics of sterane and triterpane types in saturated hydrocarbon fractions were analysed by GC-MS (SIM method). Significant amounts of n-alkanes have not been detected. The MS-chromatogram revealed only marginal amounts of pristane and phytane in sample P1. Pristane and phytane occurred in sample P8, and in even higher quantities in the final sample P12. The proceeding bioremediation process was accompanied by the decrease of the relative amounts of pentacyclic terpanes of hopane type, compared to tri- and tetracyclic terpanes. In the initial sample P1 the distribution of steranes and hopanes follows a pattern, which is characteristic for crude oils. However, their identification by SIM method was not possible in samples P8 and P12 because of the reduced concentration. The observed changes in the alkane fractions’ compositions may be considered as atypical, referring to the fact that during oil biodegradation under natural conditions, decomposition of isoprenoids occurs much easier and faster than decomposition of polycyclic alkanes of tri-, tetra- and pentacyclic terpane, sterane and diasterane types, after the decomposition of n-alkanes has been almost completed.  相似文献   
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Purpose  

Serpentine soils exist in many regions around the world; they are naturally enriched with nickel (Ni). An adequate understanding of soil processes determining Ni solubility is a special need particularly since less research has been addressed to Ni behavior under dynamic and controlled redox conditions. Our aim was (1) to characterize the properties of a serpentine soil and (2) to determine the impact of predefined redox windows on the mobility and dynamics of Ni in a serpentine soil.  相似文献   
66.
The impact of storm water runoff on a small urban stream   总被引:2,自引:0,他引:2  
Background, aim, and scope  In urban areas, storm water runoff often transports various pollutants, some of which settle and form sediments. In order to have the comprehensive view of the ecological state of storm water runoff recipients, both water and sediments of the stream must be assessed. In the Baltic Sea Area, the Water Framework Directive & HELCOM Recommendations aim to prevent or minimise pollution caused by harmful substances arising from storm water runoff, in order to promote the ecological restoration of the Baltic Sea—one of the most vulnerable seas. The aim of the study was to investigate the toxicity of bottom sediments of a small storm water runoff recipient focusing on the potential impact of successive discharges of urban storm water. Some storm water runoff quality parameters and the toxicity of bottom sediments of recipients was studied in this research. Materials and methods  During 9 years, at four discharge points, minimum four grab samples per year at each discharge point were taken for chemical characterisation. General parameters (pH, SS, BOD7, CODCr and TPH) in liquid phase samples were analysed according to standard methods. Annual limit values were taken from the Lithuanian EPA requirements for the management of storm water runoff with a focus on prevention and control of contamination. Eleven composite samples of stream bottom sediments, each consisting of ten sub-samples, were collected in 2006. Toxicity screening from sediments was performed using the plant Lepidium sativum according to modified I. Magone’s methodology (Magone I, Bioindication of phytotoxicity of transport emission. In: Kachalova O-L, Zinatne (eds) Bioindication of toxicity of transport emissions in the impact of highway emissions on natural environment. Riga, pp 108–116, 1989). The level of toxic impact of Lepidium sativum (compared to control) was assessed according to the modified method of Wang (Rev Environ Contam Toxicol 126:88–127, 1992). Results  The mean pH of urban storm water runoff does not vary much from neutral, but range values are quite different, from 4.0 up to 8.7. The highest concentration of SS reached 800 mg L−1, TPH—2.4 mg L−1, BOD7—300 mg O2 L−1 and CODCr—1,400 mg L−1. The SS was above the limit in 64% of total amount of grab samples, TPH—37%, BOD7—41% and CODCr—55%. The toxicity analysis of the bottom sediments showed varying toxicity of bottom sediments along the stream. From nine analysed samples of bottom sediments, 30% had weak toxicity, 30% medium and 30% strong toxicity on the test organism plant L. sativum. There was one single sample with no toxic effects, so that the results showed that urban storm water has an unacceptable environmental impact on recipients. It was also indicated that storm water runoff discharge alone is not the potential source of toxicity of bottom sediments. The litter demonstrated a weak toxicity of bottom sediments as well. Discussion  Most local authorities do not consider storm water runoff discharges to be a matter of great concern because they believe that surface runoff arising from rainfall is still relatively clean. The study showed that the current method of monitoring storm water runoff quality by chemical analyses is not the best tool for environmental impact assessment and must be combined with toxicity tests of bottom sediments of recipients. Recommendations and perspectives  To avoid the environmental impact of storm water runoff more attention should be paid to the development and implementation of storm water runoff pollution prevention measures. The study implies that future research concerning the relationships between storm water runoff deposit characteristics and biological activities must be developed to evaluate the contamination potential of stream sediment deposits for local aquatic ecosystems. Further studies should be developed to characterise the activities of the microbial community of storm water runoff sediments, and to monitor bioremediation in situ.  相似文献   
67.
A review is given in this paper of the up-to-date results observed in differentiation and transformation studies on petroleum-type pollutants in underground and surface waters. Water and particulate matter derived from the locality of Pan?evo Petroleum Refinery, Serbia (River Danube alluvial formations). It was shown that distributions of n-alkanes, steranes and triterpanes, and δ13CPDB values of n-alkanes may successfully be used for qualitatively differentiating the petroleum-type pollutants from native organic matter in recent sedimentary formations. In underground waters, a petroleum-type pollutant is exposed to microbiological degradation which is manifested through relatively fast degradation of n-alkanes. Following an almost complete degradation of crude oil n-alkanes in underground water, the biosynthesis of novel, even carbon-number C16–C30 n-alkanes may be observed. It is shown that the n-alkane distribution observed in a petroleum-type pollutant may depend on the intensity of its previous interaction with water. The fate of petroleum-type pollutants in environmental waters may be predicted through laboratory simulative microbiological degradation experiments by using microorganism consortiums similar to those observed under relevant natural conditions, as well as on corresponding nutrient base.  相似文献   
68.
Water, Air, & Soil Pollution - In this pilot study, we evaluated the usefulness of the alkaline comet assay as a biomonitoring tool at the level of plankton communities affected by varying...  相似文献   
69.
Degradation Kinetics of an Aged Hydrocarbon-Contaminated Soil   总被引:1,自引:0,他引:1  
PM2.5 and PM10 samples were collected in the urban atmosphere of Elche (southeastern Spain) between December 2004 and November 2005. The samples were analyzed for mass and water-soluble inorganic ions (Na+, ${\text{NH}}^{{\text{ + }}}_{{\text{4}}}$ , K+, Ca2+, Mg2+, Cl?, ${\text{NO}}^{{\text{ - }}}_{{\text{3}}}$ and ${\text{SO}}^{{{\text{2 - }}}}_{{\text{4}}}$ ) with the aim of investigating the influence of the climatic and geographic features of a coastal semiarid area on the contribution of these species to PM levels. Secondary inorganic ions ( ${\text{SO}}^{{{\text{2 - }}}}_{{\text{4}}}$ , ${\text{NO}}^{{\text{ - }}}_{{\text{3}}}$ , ${\text{NH}}^{{\text{ + }}}_{{\text{4}}}$ ) were the major components in the fine fraction (PM2.5), accounting for 40% of the total mass. The relationship between non-marine ${\text{SO}}^{{{\text{2 - }}}}_{{\text{4}}}$ and ${\text{NH}}^{{\text{ + }}}_{{\text{4}}}$ indicated that fine sulfate particles were completely neutralized by ammonium. In the coarse fraction (PM10–2.5), nitrate (as NaNO3 and Ca(NO3)2), together with crustal (CaCO3) and marine species (NaCl) accounted for almost 50% of the total mass. Fine sulfate and coarse nitrate showed summer maximums. In contrast, the concentrations of fine ${\text{NO}}^{{\text{ - }}}_{{\text{3}}}$ were lowest in the warm period. Ammonium presented both winter and summer maximums. The levels of marine ions, except for coarse Cl?, were highest in summer when the dominant wind flow is from the sea. No significant seasonal variations were observed for coarse Ca2+ and ${\text{SO}}^{{{\text{2 - }}}}_{{\text{4}}}$ . The concentrations of all inorganic ions increased during Saharan dust events, in particular, fine ${\text{NH}}^{{\text{ + }}}_{{\text{4}}}$ and ${\text{SO}}^{{{\text{2 - }}}}_{{\text{4}}}$ and coarse $NO_3^ - $ . Coarse calcium was proved not to be a good tracer for this type of episode in our region since the average levels of this cation are elevated and the relative increase in its concentrations during African events was not as high as expected.  相似文献   
70.
With increasing demand for sustainable production, the need to effectively utilise site-based resources increases. One such resource is the remaining crop residues, both above and below ground, after harvest. In order to assess the magnitude of this resource, this study determined the plant nutrient contribution of residues from 17 different crops in seven different regions of Slovakia over a nine-year period. The soil profile 0.0–0.3?m was taken into account at belowground residues sampling. The results showed that winter rape, mustard, corn maize, triticale, winter rye with straw and sunflower left the most residues, exceeding 8 tons of dry biomass per hectare. Root crops (sugar beet, potatoes) and peas left less than 3 tons of residual dry biomass per hectare. Using these data, the nutrient potential coefficient, i.e. the amount of nutrients left by production of one ton of the main product was calculated by polynomial regression. With these coefficients and the known yield of a given crop, it was possible to calculate how much nitrogen, phosphorus and potassium each crop leaves in the soil after harvest. It was found that the amount of nitrogen left ranged from 20 to 132?kg, phosphorus from 2 to 24?kg and potassium from 13 to 218?kg per hectare. This has to be taken into account when calculating the fertiliser requirement of the subsequent crop in order to achieve better resource utilisation, thereby reducing the risk of eutrophication and improving farm profits by reducing expenditure on fertiliser.  相似文献   
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