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| Titel |
Pedogeochemical mapping of Al, Ba, Pb, Ti and V in soils of the Barcelona Province (Catalonia, NE Spain): relationships with soil physico-chemical properties. |
| VerfasserIn |
J. Bech, F. Reverter, P. Tume, M. Sokolowska, P. Sanchez, L. Longan, J. Bech, M. Zhiyanski, A. Lansac, M. T. Oliver |
| Konferenz |
EGU General Assembly 2009
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 11 (2009) |
| Datensatznummer |
250019320
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| Zusammenfassung |
| Pedogeochemical mapping is a useful tool for estimating the local background of potentially
toxic elements (PTE), wich is essential for environmental regulation.
The aim of this study is to estimate the levels and distribution of Al, Ba, Pb, Ti
and V in surface soils of the Barcelona province (Catalonia, NE Spain) and their
relationships with administrative-geographic districts, texture, pH, organic carbon and
CaCO3.
The studied region has a surface area of 7731 Km2. The geology is varied: granites and
Paleozoic shales predominate in SE-E. and Mesozoic and Cenozoic limestones, dolomites,
marlstones, gypsum and sandstones in the remainder of the studied area. 319 top soil samples
(0-20 cm) were collected at 5 km intervals on a regular grid, dried and sieved (2mm).
General soil properties were analysed by standard methods. Aqua regia digests (DIN
38414-S7) of Al, Ba, Pb, Ti and V were determined by Inductively Coupled Plasma
Spectrometry.
Statistical data treatment was carried out using SPSS 12.0 and Statgraphics Plus 5.1. We
applied Exploratory Data Analysis (EDA) techniques to statistically describe the
data.
The software used for mapping was ESRI’s Arc Wiew 9.0, Desktop version. Analytical
data is represented using growing dot maps. The values of every mapped variable were
grouped into a few cartographic classes in order to produce limited legends. The limits for the
cartographic classes were chosen by the percentile method (5th, 25th, 50th, 75th, 90th, and
98th).
Some results are: Al mg kg-1min 4410.0, max 194786.0, mean 18145.6, sd 12112.1, med
16273.3 ; Ba mgkg-1min 7.32, max 1709.0, mean 128.4, sd 149.2, med 91.7; Pb mg
kg-1min 2.76, max 485.7, mean 52.2, sd 46.3, med 46.0; Ti mg kg-1min 11.6, max 3540.0,
mean 268.0, sd 421.6,
med 132.2, and V mg kg-1min 2.15, max 289.2, mean 31.4, sd 25.7, med 26.0.
.
The highest mean value of Ba (328mkg-1), Pb (139.6 mgkg-1) and V (54.7 mgkg-1)
corresponds to the Barcelonés district with mainly urban soils. The Al contents have a
pedogenic influence (it is essential component of clay minerals). The highest mean value
(27016.7 mgkg-1) is found in the Garraf district, with abundant Luvisols located in karst
sinkholes and dolines.
The Ti concentration depends mainly of geogenic influence, thus the highest
mean value (1048.5 mgkg-1) is found in the Maresme district, over an granitic
batholite.
The maximum mean contents of Ba, Pb, and V versus pH are reached at pH 5-5.5 and the
maximum of Al and Ti are reached at pH 11.7 and the Al at % OC 4-6.3 and Ti at % OC < 0.4. |
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