Barczi Attila: A Bakony természettudományi kutatásának eredményei 24. - A Tihanyi-félsziget talajai (Zirc, 2000)

SOILS OF THE TIHANY PENINSULA AND THEIR ROLE IN SUSTAINABLE AGRICULTURE

varied so greatly, that from the data gathered it is impossible to make any general extrapolations. Through the assessment of maps and data it was confirmed that human interference has altered soils significantly. Nature conservation has restored the original status, re-flooded the previously drained areas and reafforested the once larger forest areas. Our data shows that the rate of built-up areas has grown significantly, and soil degradation, primarily on arable land and in vineyards has accelerated. Already at the beginning of the 20th century agricultural land-use failed to pay attention to soil conditions. The inhabitants of the area derive their incomes primarily from tourism and agriculture, in spite of the fact that both activities can damage the natural heritage and soils of the peninsula. In order to address this problem, the areas unsuitable for arable production or viniculture were identified. The necessity of this work was highlighted by a few arable areas (e.g. Gödrös) where soil degradation is rather advanced. From soil studies and data series, with the assistance of frequency diagrams and field studies, it was shown that extreme clay or sand, excessively alkaline or acid soils did not inhibit the agricultural use of the peninsula's land. Despite a shallow productive fertile soil layer (0-40cm), extreme water management conditions and a tendency for erosion rule out the possibility for intensive land use. I have superimposed areas with shallow productive soil strata or steep slopes together with extreme water management onto three map layers. A contour map was created by converting the relief map using a GIS programme. The shallow soil stratum areas were mapped by interpolating data taken from the soil sections and with the auger samples. To represent the influence of water we used soil blocks identified in the genetic soil map. By superimposing 3 different layers upon one another we were able to determine soils of the Tihany Peninsula which are unsuitable for arable farming or viniculture, and soil areas which are vulnerable to degradation through intensive cultivation. The belt of hills surrounding the peninsula, the mosaic of variegated terrain (Gejzír-mező, Gödrös, and Diós), and also of edges of the lakes and wetlands are unsuitable for intensive agricultural use. At the same time these areas can enjoy a preferential position in the planning of a biotope network, for the creation of wildlife corridors. Recommendations (for theoretical and practical use) • The Pürckhauer-type auger provides a simple and efficient tool for soil mapping. From the experience of this research we recommend using it primarily for taking rough soil samples, and to determine the depth of the productive soil sections. It is also necessary to excavate soil profiles. With the use of the auger method the number of soil sections can be reduced. • The identification of transitional soil categories in genetic and soil geographical classification is difficult (e.g. chernozem meadow-meadow chernozem soils). There is additionally an important task to supplement the existing classification system. This supplementation can be partly based on data derived from laboratory analysis, which specify significantly different parameters between different soil types. • Computerised data processing, in spite of being an excellent methodological procedure, will only bring good results if treated with a critical eye and backed up with field experience and with the observational aptitude of the cartographer.