HR: 1340h
AN: GP53B-1213    [Abstracts]
TI: Dynamics of Anthropogenic Ferrimagnetics (fly-Ashes) in Soils - Experiments on Test Fields
AU: * Kapicka, A
EM: kapicka@ig.cas.cz
AF: Institute of Geophysics ASCR, Bocni II/1401, Prague 4, 14131, Czech Republic
AU: Petrovsky, E
EM: edp@ig.cas.cz
AF: Institute of Geophysics ASCR, Bocni II/1401, Prague 4, 14131, Czech Republic
AU: Fialova, H
EM: hfialova@ig.cas.cz
AF: Institute of Geophysics ASCR, Bocni II/1401, Prague 4, 14131, Czech Republic
AU: Kodesova, R
EM: kodesova@af.czu.cz
AF: Czech Agriculture University, Kamycka 129, Prague 6, 16521, Czech Republic
AB: Magnetic properties of recent soils are often studied with the aim to asses the level of contamination due to atmospheric deposition of pollutants. In order to interpret properly magnetic data, several factors have to be taken into account. Lithogenic effect on top soil magnetic properties, pedogenic processes in soils, magnetic stability of anthropogenic ferrimagnetics in real soil conditions have been discussed in earlier studies. The other limiting effect, quite omitted in the past, is possible migration of anthropogenic farrimagnetics in vertical soil profiles. In our contribution we report on experimental investigation of temporal variation of power-plant fly ashes under different soil properties (soil, grass, sand), as well as different land morphology. In experiments on test fields we used fly ashes from two coal-burning power plants, showing relatively narrow grain-size distribution, with the mean of 10.5 ƒÝm. Magnetite and/or maghemite was identified as dominant ferromagnetic phase. Temporal variations of vertical distribution of magnetic susceptibility along soil columns, with surface artificially contaminated by the power-plant fly ashes, were investigated using MAGPROX SM400 susceptibility meter. Our preliminary results, covering a period of more than one year, indicate that vertical distribution of particles in topsoil layers is in the investigated cases relatively stable. Vertical migration of deposited particles is practically buffered in the top 1-2 cm, and surface magnetic susceptibility was not distinctly modified. On the other hand, surface dynamics of anthropogenic ferrimagnetics may be radically affected by water regime (precipitation) especially during the winter period. This resaerch was carried out within GA AVCR Project No IAA300120701.
DE: 0478 Pollution: urban, regional and global (0345, 4251)
DE: 1512 Environmental magnetism
SC: Geomagnetism and Paleomagnetism [GP]
MN: 2007 Fall Meeting