Fjölrit RALA - 15.06.2004, Blaðsíða 82

Soils developed in volcanic material in Hungary
Gy. Fuleky1, Á. Kertész2, B. Madarász2, O.Fehér1
1 Szent István University Department ofSoil Science and Agricultural Chemistry, Gödöllo, Hungary
2Hungarian Academy ofSciences, Geographical Research Institute,Hungary
The neogenic volcanism has two basic types in the Carpathian basin. In Hungary, the major
part of the Northem Uplands belongs to the Inner-Carpathian volcanic belt. The volcanic
activity occurred in the Miocene and Pliocene, with the mountains getting younger from SW
to NE. Intermediary and acidic lava and pyroclastics are the products of the volcanic activity,
with an increasing silicate content. The other type of the volcanism is the basaltic volcanic
activity related to faults. The basaltic volcanism may be estimated to have taken place in the
postpannonian period, 6-2.2 million years BP, including Transdanubian Uplands and the
basalt occurrences in Nógrád district.
Soil profiles were discovered on different volcanic materials in Hungary: on andesite (Tokaj
N 19 and Magas-Tax) on rhyolit tuff (Andomaktálya and Tolcsva), on basalt (Badacsony N
18) and basalt tuff (Tihany N 17).
Considering the parameters of andosol properties of the investigated soil profiles we can
conclude that the andosol properties of investigated 3 soil profiles do not fulfil the criteria of
andic, vitric properties. (Table 1.)
According to the X-ray diffraction analysis illite was the dominant (76-93%) clay mineral
followed sometimes by smectite (N 17 9-19%, N 18 2-7%, N 19 0-1%). These results also
prove the evidence of former loess contamination at the investigated profiles.
Considering the non-European volcanic soil profiles we can conclude that in the case of
Andomaktálya and Tolcsva soils developed on rhyolite-tuff do not completing any criteria of
andic, vitric properties. Same in case of Magas-Tax developed on andesite in Börzsöny
Mountains.
Only the profile in Mátra Mountains, in Galyatetö developed on andesite is close to andic
properties with bulk density of 0,7, organic matter of 7-8% and a phosphate retention of 61%.
The Alo+l/2Feo content of this profde is the nearest to 1% among all the Hungarian profiles.
It is interesting to mention the ecological conditions of the last location: altitude above 900 m,
precipitation more than 700 mm, temperature is cooler then at the other profiles, vegetation is
evergreen forest, parent material is andesite.
We can conclude that in Hungary located at the lower part of the Carpathian-basin both the
quality of volcanic material (age, weathering etc.) and the ecological conditions are not
favourable for andosol development. On volcanic material rather Cambisols, Phaeozems,
Umbrisols etc. could develop and only on the higher points of the Carpathian mountains both
in Slovakia and Romania andosols could be found. The classification of the Hungarian
volcanic soils:
N 17 - Tihany: diagnostic: molhc, no-calcic, xeric
WRB: haplic Phaeozems
US.ST: typic Haploxerrols
RPF: Calcisol calci-magnesique, sur tuf basaltique, rather than Phaeosol.
N 18 - Badacsony: Umbric, an acid pH and probably BS<60% fit with umbric and dystric
qualifers;
under this type of forest in some altitude xeric, a transition to ustic; dark cloloured and
high C content fit with humic qualifier.
WRB: humic Umbrisols
US. ST: dystric Xerochrepts
RPF: Brunisol mésosaturé humique, éolico-culluvial sur basalte altérée.
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