Fjölrit RALA - 15.06.2004, Síða 36

Slovakian “Andozem” in the frame of Andosols in Europe
J. Balkovic1, B. Juráni2
lSoil Science and Conservation Research Institute in Bratislava
2Department of Soil Science, Faculty ofNatural Science, Comenius University in Bratislava
Some volcanic mountains in Slovakia, namely those which are built by Neogene andesite
rocks, are somewhere covered by Andosols (“Andozem” in Soil Classification System of
Slovakia). The contribution deals with basic characteristics of andic properties of Slovakian
profiles in the frame of European Andosols. Moreover it also deals with some specific andic
properties aiming to show that andic soils in Slovakia fulfill an assumption for being
classified as Andosols. We used four COST profiles of Slovakian volcanic soils (N 21 SK - N
24 SK). They are tentatively classified as Sili-Dystric Andosol (N 21 SK), Sceleti-Dystric
Andosol (N 22 SK), Andic Cambisol (N 23 SK) and Fulvi-Sceleti-Dystric Andosol (N 24
SK). Basic classification attributes of studied profiles are summarized in table 1.
Table 1 Basic soil properties relevant for describing andic soil profiles
Prof.
N21
SK
N22
SK
N23
SK
N24
SK
Notes:
Hor. Corg Sio Alo Alp Feo Fep All. Fer. Pret pH (NaF) BD Colour
% % % % % % % % % g.cm3 wet
A 10.2 0.35 1.56 1.24 0.32 0.54 1.9 0.6 98.20 10.30 0.66 10YR2/1
Bwl 2.10 0.96 3.28 0.91 0.62 0.02 8.8 1.1 99.74 11.06 0.80 7.5YR4/4
Bw2 0.42 010 0.78 0.27 0.41 0.02 - 0.7 76.33 9.50 1.21 7.5YR4/5
A 10.8 0.04 0.68 0.67 0.98 0.58 0.2 1.7 85.53 7.93 0.69 10YR2/1
A/B 5.85 0.25 1.92 1.96 0.85 0.52 1.0 1.5 98.50 10.88 0.83 5YR 2.5/3
Bw 1.92 0.57 2.07 0.85 0.56 0.03 4.5 1.0 97.33 10.89 0.86 10YR4/4
Ahl 7.20 0.10 0.59 0.54 0.59 0.14 0.50 1.0 65.38 8.96 0.72 10YR2/1
Ah2 4.65 0.05 0.61 0.58 0.58 0.14 0.20 1.0 68.46 9.04 0.78 10YR3/2
Bw 2.55 0.06 0.69 0.51 0.58 0.12 0.70 1.0 69.97 9.43 0.92 10YR4.5/3
Ahl 15.9 0.03 0.39 0.20 0.54 0.30 - 0.9 61.2 7.73 0.73 10YR2/1
Ah2 12.0 0.22 1.23 1.04 0.38 0.05 1.2 0.7 98.4 10.78 0.65 10YR2/2
A/B 8.40 0.44 1.94 1.37 0.31 0.09 2.6 0.5 98.1 11.59 nd 10YR3/2
Bw 6.0 1.18 3.18 0.44 0.21 0.04 10.1 0.4 99.3 11.68 nd 10YR3/3
B/C 0.90 0.86 1.51 0.45 0.05 0.03 5.0 0.1 96.6 11.26 nd 10YR4/4
organic carbon content (Corg), oxalate silica, aluminium and iron (Sio, Alo, Feo), pyrophosphate aluminium and iron
(Alo, Feo), allophane 100/[(-5.1(Alo-Alp)/Sio) + 23.5]Sio (All.), ferrihydrite 1.72Fe (Fer.), exchangeable alkalinity in
1N NaF (pH(NaF)), bulk density at field moismre (BD), nd - not determined
Described profiles show a variety of andic soils in Slovakia from weakly developed Andic
Cambisols (N23SK), through “sil-andic” Andosol (N21SK) ending at well developed Fulvic
Andosols (N24SK). This sequence relatively accurately describes the general andic catena in
Slovakian volcanic mountains as it is schematically presented in figure 1. We can follow
some general geographical rules in distribution of sil-andic and alu-andic horizons in
dependence on altitude and precipitation.
Selective dissolving extractions indicate that reactive aluminium in sil-andic horizons of
Slovakian Andosols shows the Al/Si ratio between 1 and 2.5, what is probably because of
allophane like minerals with gibbsite admixture (Balkovic et Bartosová, 2003). Based on the
same source we can assume that organically associated reactive A1 prevails in alu-andic soil
horizons, where it is accompanied by “opaline” silica. These genetic mles intimately reflect
the Al-solubility mechanisms and Al/Si - ion speciation estimated in horizons of Slovakian
volcanic soils (Balkovic et Slivková, 2002a). Studied soils have the effective mechanisms for
specific anion sorption. Some quantification of these typical andic properties from Slovakia
are presented by Balkovic et Slivková (2002b).
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