Srovnání mrazových kopečků v Hrubém Jeseníku a na Islandu

Abstract

This paper is focused on comparation of frost hummocks in the Hrubý Jeseník Mts. and in the Mosfellsheiði area in Iceland in terms of their external and internal characteristics as well as their thermal characteristics. Field work in Mosfellsheiði provided height, length, and width data of more than 120 frost hummocks which were analyzed and compared to frost hummocks in Keprník and Tabulové skály location in the Hrubý Jeseník Mts. Soil samples from frost hummocks were taken to determine frost susceptibility of soils. Based on ground temperature measurements at depth of 15 and 30 cm in the frost hummocks in Iceland and the Hrubý Jeseník Mts., freeze-thaw cycles were investigated. The results show that frost hummocks in the Hrubý Jeseník Mts. are larger but less domed-shaped than those in Mosfellsheiði. Further, soils in frost hummocks are frost susceptible. The highest numbers of freeze-thaw cycles were identified in Iceland. It was also found out that freeze-thaw processes occurred in the frost hummocks in Tabulové skály but in Keprník location were very few freeze-thaw cycles observed. Short term freeze-thaw cycles at the end of regelation seasons mostly show diurnial frequency. At the 30 cm depths only one or two regelations were observed during a single season. Powered by TCPDF (www.tcpdf.org)