摘要:

With the present investigation, which included in the first place the intensively used regions of Switzerland, it was tried to give a general view of the soil contents of lead, cadmium, copper, nickel and zinc. Using the extraction method with 2MHNO3, described in the “Ordinance Relating to Pollutants in Soil” (VSBo), approximated and not real total contents were determined. It was found that the values mostly lie below the guide levels in the VSBo. The influence of different site factors (geology, land utilization, aerosol emissions from industry, incineration plants and traffic) on the heavy metal contents in soil are discussed. Proceeding from the contents in the subsoil, indications about natural basic contents are made.

ISSN:0306-7319    

DOI:10.1080/03067319208026992

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Mobility is a concept frequently used in soil science to estimate the risk of contamination of other environmental compartments. However some confusion exists over the definition of mobility, originating from the fact that this term is used in different fields. Consequently many operational parameters have appeared in relation to mobility estimation. This leads to great difficulties in comparatively interpreting practical data obtained under different conditions, and especially the biological significance of mobility. A standardization of the definition of mobility, taking into account the time scale, should be recommended.

ISSN:0306-7319    

DOI:10.1080/03067319208026993

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

The effect of liquid animal manure on heavy metal solubilization in soil has been studied in the laboratory; three different types of experiments were carried out:

ISSN:0306-7319    

DOI:10.1080/03067319208026994

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Heavy metal balances of a reed bed system (soil pH > 7, carbonate content about 30%) continuously flooded with sewage during 5 years indicate that only Pb, Zn, Cd and Cu were partly stored in the soil. Strong reductive conditions, high sewage percolation and metal complexation with soluble organic compounds caused a considerable leaching of Fe, Mn, Ni and Cr from the soil and formation of amorphous iron oxides. The results indicate that continously flooded reed bed systems with high percolation rates are not suitable for the elimination of heavy metals. Conversely, it should be possible to purify metal contaminated soils through percolation of sewage with low metal content.

ISSN:0306-7319    

DOI:10.1080/03067319208026995

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Natural organic chelating agents take part in the mobilization and translocation of heavy metals in unpolluted and polluted soils. They also have to be considered as possible extracting agents for the decontamination of heavy metal polluted soils. For an assessment of the desorption capability of glycinc, heavy metals (Cd, Cu, Ni, Pb, Zn) were adsorbed onto typical soil components (bentonite and peat). The metal loaded sorbents were resuspended in aqueous solutions of glycine at pH 7.0 and 4.5 and the quantities of the desorbed metals were analysed in the liquid phase. Furthermore, the dependency of the desorption rate on the duration of experiments and the metal content were investigated. The remobilization of heavy metals from bentonite by glycine at pH 7.0 decreases following the order Cu > Ni > Zn > Cd > Pb and ranges from 95% to 9.5%. The desorption rate was significantly lower at pH 4.5 and in suspensions of peat.

ISSN:0306-7319    

DOI:10.1080/03067319208026996

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

A new spectrophotometric method is described for the determination of thallium in soil by extraction of Tl(III) with a toluene solution of N,N′-diphenylbenzamidine after acidification with 0.2–4.0 M HCl, and reaction of the extract with Crystal violet in the presence of 0.01–0.8 M HCl. The value of molar absorptivity of Tl(III)-X-CV complex (where X = Cl or Br; CV = Crystal violet) in toluene is 7.00 × 1041 mole−1cm−1at the absorption maximum of 610 nm. The detection limit of the method is 20 ng ml−1. The present method is free from interference of almost metal ions commonly associated with Tl. The method has been applied for analysis of the metal to soils.

ISSN:0306-7319    

DOI:10.1080/03067319208026997

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Surface accumulation of lead in urban soils is a well-known phenomenon but its marked accumulation in remote, upland areas is less well documented. Such enrichments (up to 500 mg/kg) could be a potential hazard to grazing sheep.

ISSN:0306-7319    

DOI:10.1080/03067319208026998

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Several commonly used sequential chemical extraction procedures of heavy metals in soils and sediments are compared, and their advantages and disadvantages are discussed focusing on selected case studies. In particular, problems caused by handling of anoxic samples, and of specific phases (e.g. organic fractions and sulfides) are addressed.

ISSN:0306-7319    

DOI:10.1080/03067319208026999

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Prediction of plant contamination on the basis of environmental conditions seems to be an important task. In order to assess the suitability of three soil extractants and seedlings as a prediction media for the content of Cd and Zn in mature plants, three independent pot trials were conducted. In these trials six soil types of different properties were used. The total number of pots was 160 (40 variants in 4 replicates). Soils were artificially contaminated by Cd and the selected variants also by Zn. The contents of Cd and Zn in soil extractants and seedlings were compared with the contents of these elements in corn mature plants (roots and stems) by means of regression analysis. For cadmium, the best results as to the prediction of its content in mature plants were obtained with NaNO3, whereas for zinc the best results were given by the seedlings.

ISSN:0306-7319    

DOI:10.1080/03067319208027000

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Mobility and toxicity of heavy metals are largely controlled by chemical reactions which take place at the oxide/water interface. Insights in the mechanisms involved in these reactions can be obtained from the recently developed synchrotron-based fluorescence-yield X-ray absorption spectroscopy. The phenomena investigated in the present study are: the precipitation of Cr(HI), its coprecipitation with Fe(III), its sorption onto goethite (αFeOOH), and its oxidation at the surface of a Mn(IV) oxide, birnessite. These examples are used to show how a combination of macroscopic and spectroscopic information provides a mechanistic picture of the mobilization and immobilization pathways of heavy metals in natural systems.

ISSN:0306-7319    

DOI:10.1080/03067319208027001

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor