Type of micromorphological structure in Rendzic Leptosols from the Małopolska Upland (Poland).
Zbigniew Zagórski, Division of Soil Science, Department of Soil Environmental Sciences, Warsaw Agricultural University - SGGW, Nowoursynowska 159, Warszawa, Poland
Results of micromorphological analyses of soils from selected parts of the Małopolska Upland (southern Poland) representing Rendzic Leptosols developed from Devonian, Jurassic, Cretaceous and Tertiary limestones are presented. Based on microscopic analyses, five main types of micromorphological structure of rendzic soils are presented in relation to the lithological-petrographic properties of the soil substrate. i. residual – characteristic of soils developed from massive sparitic limestones; ii. carbonate I – characteristic of soils developed from pelitic plate limestones; iii. carbonate II – characteristic of soils developed from soft marls and chalk; iv. illuvial – characteristic of soils developed from partly decalcified marly opokas; v. mixed – characteristic of soils developed from different types of limestones. Clay plasma is the indicator of the residual type. Its red or brownish colour and the large content of kaolinite suggest that the soil substrate represents residuum after karst processes. Carbonate plasma plays a crucial role in the carbonate types. Due to the distinct differences in the microstructure, two carbonate types have been distinguished – one for pelitic limestones and the second for marls and chalk. The specific structure of the illuvial type results from the presence of clay plasma derived from in situ weathering of carbonate rocks. The characteristic fabric indicates contemporaneous illuviation processes. The mixed type has been distinguished mainly for soils developed from limestones with the prevailing admixture of detritic silica material – mainly quartz grains. The main indicator of this type is the presence of fragments of carbonate rocks in the microskeleton.