Periglacial Landforms of the Hrubý Jeseník Mountains
World geomorphological landscapes, 2016
This chapter deals with the occurrence, morphology and activity of periglacial landforms in the H... more This chapter deals with the occurrence, morphology and activity of periglacial landforms in the Hrubý Jesenik Mts. Redistribution of snow during the Last Glacial period , cold climate and the presence of extensive planation surfaces at high elevations have created favourable conditions for the formation and evolution of periglacial landforms, some of which are preserved to this day. Most of these landforms are relict (tors , frost-riven cliffs , cryoplanation terraces , blockfields , sorted polygons and nets, and large solifluction steps ), and only a small part of climatically less demanding periglacial landforms are active (ploughing blocks , earth hummocks , small sorted circles , nivation hollows and small solifluction lobes ). Special attention is paid to patterned ground , which provides information about current and past freeze-thaw effectiveness. Earth hummocks, found at wind-swept sites, on frost-susceptible, fine-grained regoliths, are the most interesting type of patterned ground. Evidence of present-day activity of earth hummocks are distorted soil horizons, vertical and horizontal displacement of clasts, cryoexpulsion features and cracks on crests of earth hummocks, frequent freeze-thaw cycles and long-term freezing. The origin of earth hummocks has been identified as being at the break of the Subboreal /Subatlanti c. The occurrence and activity of earth hummocks, sorted circles and ploughing blocks at several sites above the alpine timberline of the Hrubý Jesenik Mts. allows us to regard these areas as parts of the mountain periglacial zone .
How geomorphologic processes on slopes affect mid-mountain valley headwalls during the post-glacial history: a multi-methodical approach from the High Sudetes Mts
EGU General Assembly Conference Abstracts, Apr 1, 2018
Debris flows in mountainous areas have a deep geomorphic impact on slope dynamics. Their activity... more Debris flows in mountainous areas have a deep geomorphic impact on slope dynamics. Their activity corresponds with heavy rainfall events. The estimation of these events depends not only on meteorological prediction but also on the knowledge of their spatial occurrence. As debris flows usually occur in the same paths with different frequencies during the Quaternary period, spatial data are needed to obtain more detailed information about debris flow phenomena. This was the reason for the creation of the presented map of debris flow features in the Hrubý Jeseník Mts. A total of 95 debris flow paths and 47 debris flow accumulations (including lobes or levees) have been mapped in the field. A comprehensive spatial database of debris flow features is shown in the map, which could be helpful for future research of Quaternary geomorphic evolution of the landscape and for forest management and state administrative authorities in future planning.
Stan et al. (2017) investigated the internal structure of two periglacial blockfields on the Ztra... more Stan et al. (2017) investigated the internal structure of two periglacial blockfields on the Ztracené kameny site, Eastern High Sudetes, Czech Republic, using electrical resistivity tomography and seismic refraction tomography and interpreted two high-resistivity and high-velocity zones as remnants of the Pleistocene permafrost. However, we believe that in reality no permafrost occurs on the site, and we provide alternate, nonpermafrost interpretations of the geophysical measurements by Stan et al. (2017) that are well consistent with other evidences such as climate and topographic attributes of the blockfields, permafrost-disqualifying ground thermal regimes, and common characteristics of mid-latitude, low-altitude permafrost locations from elsewhere. We also rectify some misconceptions about the study site that are stated by Stan et al. (2017).
Zákonitosti prostorového rozmístění periglaciálních tvarů v Krkonoších nad alpínskou hranicí lesa =Natural relations of spatial distribution of periglacial landforms above the alpine timberline in the Giant Mountains (Czech Republic)
Geomorphological consequences ot the 2002 flood in the Otava river drainage basin
Geomorphological consequences of the 2002 flood were mapped in the Otava river drainage basin. Fi... more Geomorphological consequences of the 2002 flood were mapped in the Otava river drainage basin. Field mapping was focused on relief changes m river beds and 1oodplains and on 1ood geomorphological indications in adjacent slopes. Geomorphological consequences of the hood according to anthropogenic impacts into floodplains were assessed12513
Geografie. Sborník České geografické společnosti, 1999
The author describes surface and undersurface landforms in the Cecher Hill (the Outer Western (Fl... more The author describes surface and undersurface landforms in the Cecher Hill (the Outer Western (Flysch) Carpathians) and outlines their origin and development. The main part of the article focuses on periglacial and pseudokarst (above all a pseudokarst cave in the Cecher Hill) landforms in this area. It also describes periglacial processes in the Pleistocene and the processes of humid character in the Holocene, which formed these landforms. The author takes notice of the relationship between landforms and geological conditions in the area. KEY WORDS: the Hostynske vrchy Hills-the Cecher Hill-frost-riven cliff-pseudokarst-pseudokarst cave. Uvod Vrch Cecher (461,5 m n. m.) se nachazi u obce Rusava pri soutoku bystrin Rusavy a Raztoky (obr. 1) a nalezi do geomorfologickeho okrsku Rusavska hornatina. Ta je sOu<':asti podcelku Hostynskych vrchu (291 km 2) s nadraze
Geografie. Sborník České geografické společnosti, 2003
z e k: Characteristic features of frost-riven cliffs: comparison of active frost-riven cliffs in ... more z e k: Characteristic features of frost-riven cliffs: comparison of active frost-riven cliffs in the world anrj (non-active) frost-riven cliffs in the Rusavskd hornatina (Mts.).-Geografie-Sbornik CGS, 108, 4, pp. 261-276 (2003). The author describes frost-riven cliffs, their occurrence, origin and development in different part of the world. He also focuses on periglacial processes (e.g. gelivation, cryoplanation) in the Pleistocene, which formed these landforms, and on processes of humid character in the Holocene, which influence and reform these frost-riven cliffs. The author compares frost-riven cliffs in the Rusavska hornatina (Mts.) (Moravian Carpathians) and frost-riven cliffs in other places of the world. He explains the difference between active frost-riven cliffs and "passive" frostriven cliffs. KEY WORDS: frost-riven cliff-periglacial conditions-cryoplanation terrace-the Rusavska hornatina (Mts.). Venovano pamatce skveleho cloveka, odbornika a ucitele prof. RNDr. Iva Chlupace, DrSc.
Geografie. Sborník České geografické společnosti, 2007
z e k, v. T rem I, Z. Eng e I: Lithologic predisposition, morphology, and spatial distribution ,o... more z e k, v. T rem I, Z. Eng e I: Lithologic predisposition, morphology, and spatial distribution ,of patterned ground above alpine timberline in the High Sudetes.-Geografie-Sbornik eGS, 112, 4, pp. 373-387 (2007).-It is evident that morphology and location of the patterned ground of the High Sudetes are significantly dependent on lithological conditions. Additional impact has also extreme location, respectively extend of its deflation. The occurrence of sorted polygons is dependent particularly on quartzite; earth hummocks prefer rocks offering fine-grainedlsmall-grained waste. Sorted polygons reach the largest horizontal sizes among all kinds of patterned ground, earth hummocks have the smallest horizontal sizes. Many temporary forms among all kinds of patterned ground exist in the High Sudetes which is due to their polycyclic, respectively polygenetic evolution. KEY WORDS: lithology-morphology-patterned ground-High Sudetes.
Derivation of palaeo-air temperature conditions from past periglacial features
&lt;p&gt;Permafrost repeatedly occurred across central Europe during cold periods of the ... more &lt;p&gt;Permafrost repeatedly occurred across central Europe during cold periods of the Pleistocene, as evidenced by a number of past periglacial features that are present in both highland and lowland areas. Many of those periglacial features, such as frost wedges and other kinds of patterned ground, cryoturbations, or pingo scars, have been widely utilized to estimate past air temperature conditions. However, the reconstructions have only relied on temperature thresholds of active periglacial features that are now mostly found in high-latitude periglacial environments. Such empirical interpretations have thus often been considered problematic and of limited validity.&lt;/p&gt;&lt;p&gt;Nevertheless, periglacial features mostly form as a result of recurrent freeze-thaw processes that act within the active layer over permafrost, the base of which is commonly sharply defined and limits the subsurface extent of periglacial features. The active-layer thickness (~depth of maximum annual thaw) usually attains several decimetres to metres, which mainly depends on summer and annual temperature conditions. Since the thickness of palaeo-active layer can be determined based on past periglacial features, it can thus also be used to estimate the temperature conditions that gave rise to an active layer of a given thickness.&lt;/p&gt;&lt;p&gt;Here, we present a novel model we have devised that uses the above principles. The palaeo-mean annual air temperature modelled so far at two lowland sites in the Czech Republic where Last Glacial cryoturbations occur ranged between &amp;#8722;7.0&amp;#177;1.9 &amp;#176;C&amp;#160; and &amp;#8722;3.2&amp;#177;1.5 &amp;#176;C, and its corresponding decline compared to the 1981&amp;#8211;2010 period was between &amp;#8722;16.0 &amp;#176;C and &amp;#8722;11.3 &amp;#176;C, which agrees well with reconstructions utilizing various palaeo-archives. These initial results are promising and suggest that the model could become a useful tool for reconstructing Quaternary palaeo-air temperatures across vast areas of mid-latitudes and low latitudes where relict periglacial features frequently occur, but their full potential remains to be exploited. Additionally, it could help us refine existing and/or provide new insights into past periglacial environments that cannot be unveiled by other abiotic or biotic indicators.&lt;/p&gt;&lt;p&gt;The research is supported by the Czech Science Foundation, project no. 21-23196S.&lt;/p&gt;
This article deals with channel bars, flood accumulations of floodplain and bank scours as the mo... more This article deals with channel bars, flood accumulations of floodplain and bank scours as the most important geomorphologic effects of the spring flood in Sázava River in 2006. The article deals particularly with its spatial distribution with regard to the channel position and weirs. Relation between basic characteristics of sediments of these channel bars is surveyed. Spatial and statistical analyses were done in ArcGIS 9.2 and STATISTICA 8 Standard based on input data from field geomorphological mapping after the flood in 2006, it follows that there is a relation between spatial distribution of channel bars and flood accumulations in floodplain. There is also a relation between channel bars and bank scours. It emerged that spatial distribution of channel bars, flood accumulations in floodplain and bank scours is uneven and connected to weirs whose immediate effective sedimentary influence reaches in Sázava River to 60 m distance. Smaller channel bars connected to banks are typical for parts of river which are not influenced by weirs. Channel bars can be used for placement prediction of flood accumulations in floodplain.
The article deals with changes of setting of channel bars which originate from the overbank flood... more The article deals with changes of setting of channel bars which originate from the overbank flooding events. Channel bars carry information about a flow behavior during and out of flooding. They characterize processes inside the river channel. Characteristics of bars, (location of the channel, length, width of bars, granularity, gradation setting etc.) as well as their changes during the flood are described by statistical methods (ANOVA, correlation). Correlation matrix detecting relations between all studied characteristics of channel bars before and after the flooding was created. Causes of these changes or stability of given characteristics are analyzed in the discussion. During the September 2007 flood on Černá Opava river a number of channel bars increased, the existing accumulations particularly channel bars near bends (for example scroll bars or point bars) became larger. Channel bars got connected with the banks due to their enlargement after the flood. On the contrary, accumulations (lateral bars) placed further from bends were reduced. Faster and more complicated flow during the flood enables creation of new bars with inverse gradation.
The influence of past microclimates on the morphology and distribution of clasts is considered fo... more The influence of past microclimates on the morphology and distribution of clasts is considered for relict large-scale sorted polygons in the Krkonoše Mountains (Czech Republic). Sixty-two sorted polygons with an average length of 194 cm and an average height of 21.5 cm were measured at four sites on Mt Luční hora, at elevations of 1455 to 1555 m asl. The polygons consist of tabular clasts with a mean length of 11 cm at the borders and 5 cm in the interiors. Smaller polygons are better sorted because of the shorter distances for the clasts to reach their borders. Polygons with greater relative height are better sorted due to more intensive slope processes associated with differential frost heaving. Better sorted and more domed polygons at higher altitudes suggest more severe and longer-lasting microclimates suitable for the development of sorted polygons. The altitudinal gradient in polygon morphology and sorting suggests the dominant role of microclimate in the periglacial environment of the summit area of the Krkonoše Mountains during the Last Glacial/Holocene period. Polygon development probably involves positive feedback between morphology and frost susceptibility, driven by microclimate. The proposed method for evaluating frost sorting allows for rapid non-invasive assessment of sorting using modern methods including high-resolution remote sensing (especially terrestrial photogrammetry).
Periglacial Landforms of the Hrubý Jeseník Mountains
World geomorphological landscapes, 2016
This chapter deals with the occurrence, morphology and activity of periglacial landforms in the H... more This chapter deals with the occurrence, morphology and activity of periglacial landforms in the Hrubý Jesenik Mts. Redistribution of snow during the Last Glacial period , cold climate and the presence of extensive planation surfaces at high elevations have created favourable conditions for the formation and evolution of periglacial landforms, some of which are preserved to this day. Most of these landforms are relict (tors , frost-riven cliffs , cryoplanation terraces , blockfields , sorted polygons and nets, and large solifluction steps ), and only a small part of climatically less demanding periglacial landforms are active (ploughing blocks , earth hummocks , small sorted circles , nivation hollows and small solifluction lobes ). Special attention is paid to patterned ground , which provides information about current and past freeze-thaw effectiveness. Earth hummocks, found at wind-swept sites, on frost-susceptible, fine-grained regoliths, are the most interesting type of patterned ground. Evidence of present-day activity of earth hummocks are distorted soil horizons, vertical and horizontal displacement of clasts, cryoexpulsion features and cracks on crests of earth hummocks, frequent freeze-thaw cycles and long-term freezing. The origin of earth hummocks has been identified as being at the break of the Subboreal /Subatlanti c. The occurrence and activity of earth hummocks, sorted circles and ploughing blocks at several sites above the alpine timberline of the Hrubý Jesenik Mts. allows us to regard these areas as parts of the mountain periglacial zone .
How geomorphologic processes on slopes affect mid-mountain valley headwalls during the post-glacial history: a multi-methodical approach from the High Sudetes Mts
EGU General Assembly Conference Abstracts, Apr 1, 2018
Debris flows in mountainous areas have a deep geomorphic impact on slope dynamics. Their activity... more Debris flows in mountainous areas have a deep geomorphic impact on slope dynamics. Their activity corresponds with heavy rainfall events. The estimation of these events depends not only on meteorological prediction but also on the knowledge of their spatial occurrence. As debris flows usually occur in the same paths with different frequencies during the Quaternary period, spatial data are needed to obtain more detailed information about debris flow phenomena. This was the reason for the creation of the presented map of debris flow features in the Hrubý Jeseník Mts. A total of 95 debris flow paths and 47 debris flow accumulations (including lobes or levees) have been mapped in the field. A comprehensive spatial database of debris flow features is shown in the map, which could be helpful for future research of Quaternary geomorphic evolution of the landscape and for forest management and state administrative authorities in future planning.
Stan et al. (2017) investigated the internal structure of two periglacial blockfields on the Ztra... more Stan et al. (2017) investigated the internal structure of two periglacial blockfields on the Ztracené kameny site, Eastern High Sudetes, Czech Republic, using electrical resistivity tomography and seismic refraction tomography and interpreted two high-resistivity and high-velocity zones as remnants of the Pleistocene permafrost. However, we believe that in reality no permafrost occurs on the site, and we provide alternate, nonpermafrost interpretations of the geophysical measurements by Stan et al. (2017) that are well consistent with other evidences such as climate and topographic attributes of the blockfields, permafrost-disqualifying ground thermal regimes, and common characteristics of mid-latitude, low-altitude permafrost locations from elsewhere. We also rectify some misconceptions about the study site that are stated by Stan et al. (2017).
Zákonitosti prostorového rozmístění periglaciálních tvarů v Krkonoších nad alpínskou hranicí lesa =Natural relations of spatial distribution of periglacial landforms above the alpine timberline in the Giant Mountains (Czech Republic)
Geomorphological consequences ot the 2002 flood in the Otava river drainage basin
Geomorphological consequences of the 2002 flood were mapped in the Otava river drainage basin. Fi... more Geomorphological consequences of the 2002 flood were mapped in the Otava river drainage basin. Field mapping was focused on relief changes m river beds and 1oodplains and on 1ood geomorphological indications in adjacent slopes. Geomorphological consequences of the hood according to anthropogenic impacts into floodplains were assessed12513
Geografie. Sborník České geografické společnosti, 1999
The author describes surface and undersurface landforms in the Cecher Hill (the Outer Western (Fl... more The author describes surface and undersurface landforms in the Cecher Hill (the Outer Western (Flysch) Carpathians) and outlines their origin and development. The main part of the article focuses on periglacial and pseudokarst (above all a pseudokarst cave in the Cecher Hill) landforms in this area. It also describes periglacial processes in the Pleistocene and the processes of humid character in the Holocene, which formed these landforms. The author takes notice of the relationship between landforms and geological conditions in the area. KEY WORDS: the Hostynske vrchy Hills-the Cecher Hill-frost-riven cliff-pseudokarst-pseudokarst cave. Uvod Vrch Cecher (461,5 m n. m.) se nachazi u obce Rusava pri soutoku bystrin Rusavy a Raztoky (obr. 1) a nalezi do geomorfologickeho okrsku Rusavska hornatina. Ta je sOu<':asti podcelku Hostynskych vrchu (291 km 2) s nadraze
Geografie. Sborník České geografické společnosti, 2003
z e k: Characteristic features of frost-riven cliffs: comparison of active frost-riven cliffs in ... more z e k: Characteristic features of frost-riven cliffs: comparison of active frost-riven cliffs in the world anrj (non-active) frost-riven cliffs in the Rusavskd hornatina (Mts.).-Geografie-Sbornik CGS, 108, 4, pp. 261-276 (2003). The author describes frost-riven cliffs, their occurrence, origin and development in different part of the world. He also focuses on periglacial processes (e.g. gelivation, cryoplanation) in the Pleistocene, which formed these landforms, and on processes of humid character in the Holocene, which influence and reform these frost-riven cliffs. The author compares frost-riven cliffs in the Rusavska hornatina (Mts.) (Moravian Carpathians) and frost-riven cliffs in other places of the world. He explains the difference between active frost-riven cliffs and "passive" frostriven cliffs. KEY WORDS: frost-riven cliff-periglacial conditions-cryoplanation terrace-the Rusavska hornatina (Mts.). Venovano pamatce skveleho cloveka, odbornika a ucitele prof. RNDr. Iva Chlupace, DrSc.
Geografie. Sborník České geografické společnosti, 2007
z e k, v. T rem I, Z. Eng e I: Lithologic predisposition, morphology, and spatial distribution ,o... more z e k, v. T rem I, Z. Eng e I: Lithologic predisposition, morphology, and spatial distribution ,of patterned ground above alpine timberline in the High Sudetes.-Geografie-Sbornik eGS, 112, 4, pp. 373-387 (2007).-It is evident that morphology and location of the patterned ground of the High Sudetes are significantly dependent on lithological conditions. Additional impact has also extreme location, respectively extend of its deflation. The occurrence of sorted polygons is dependent particularly on quartzite; earth hummocks prefer rocks offering fine-grainedlsmall-grained waste. Sorted polygons reach the largest horizontal sizes among all kinds of patterned ground, earth hummocks have the smallest horizontal sizes. Many temporary forms among all kinds of patterned ground exist in the High Sudetes which is due to their polycyclic, respectively polygenetic evolution. KEY WORDS: lithology-morphology-patterned ground-High Sudetes.
Derivation of palaeo-air temperature conditions from past periglacial features
&lt;p&gt;Permafrost repeatedly occurred across central Europe during cold periods of the ... more &lt;p&gt;Permafrost repeatedly occurred across central Europe during cold periods of the Pleistocene, as evidenced by a number of past periglacial features that are present in both highland and lowland areas. Many of those periglacial features, such as frost wedges and other kinds of patterned ground, cryoturbations, or pingo scars, have been widely utilized to estimate past air temperature conditions. However, the reconstructions have only relied on temperature thresholds of active periglacial features that are now mostly found in high-latitude periglacial environments. Such empirical interpretations have thus often been considered problematic and of limited validity.&lt;/p&gt;&lt;p&gt;Nevertheless, periglacial features mostly form as a result of recurrent freeze-thaw processes that act within the active layer over permafrost, the base of which is commonly sharply defined and limits the subsurface extent of periglacial features. The active-layer thickness (~depth of maximum annual thaw) usually attains several decimetres to metres, which mainly depends on summer and annual temperature conditions. Since the thickness of palaeo-active layer can be determined based on past periglacial features, it can thus also be used to estimate the temperature conditions that gave rise to an active layer of a given thickness.&lt;/p&gt;&lt;p&gt;Here, we present a novel model we have devised that uses the above principles. The palaeo-mean annual air temperature modelled so far at two lowland sites in the Czech Republic where Last Glacial cryoturbations occur ranged between &amp;#8722;7.0&amp;#177;1.9 &amp;#176;C&amp;#160; and &amp;#8722;3.2&amp;#177;1.5 &amp;#176;C, and its corresponding decline compared to the 1981&amp;#8211;2010 period was between &amp;#8722;16.0 &amp;#176;C and &amp;#8722;11.3 &amp;#176;C, which agrees well with reconstructions utilizing various palaeo-archives. These initial results are promising and suggest that the model could become a useful tool for reconstructing Quaternary palaeo-air temperatures across vast areas of mid-latitudes and low latitudes where relict periglacial features frequently occur, but their full potential remains to be exploited. Additionally, it could help us refine existing and/or provide new insights into past periglacial environments that cannot be unveiled by other abiotic or biotic indicators.&lt;/p&gt;&lt;p&gt;The research is supported by the Czech Science Foundation, project no. 21-23196S.&lt;/p&gt;
This article deals with channel bars, flood accumulations of floodplain and bank scours as the mo... more This article deals with channel bars, flood accumulations of floodplain and bank scours as the most important geomorphologic effects of the spring flood in Sázava River in 2006. The article deals particularly with its spatial distribution with regard to the channel position and weirs. Relation between basic characteristics of sediments of these channel bars is surveyed. Spatial and statistical analyses were done in ArcGIS 9.2 and STATISTICA 8 Standard based on input data from field geomorphological mapping after the flood in 2006, it follows that there is a relation between spatial distribution of channel bars and flood accumulations in floodplain. There is also a relation between channel bars and bank scours. It emerged that spatial distribution of channel bars, flood accumulations in floodplain and bank scours is uneven and connected to weirs whose immediate effective sedimentary influence reaches in Sázava River to 60 m distance. Smaller channel bars connected to banks are typical for parts of river which are not influenced by weirs. Channel bars can be used for placement prediction of flood accumulations in floodplain.
The article deals with changes of setting of channel bars which originate from the overbank flood... more The article deals with changes of setting of channel bars which originate from the overbank flooding events. Channel bars carry information about a flow behavior during and out of flooding. They characterize processes inside the river channel. Characteristics of bars, (location of the channel, length, width of bars, granularity, gradation setting etc.) as well as their changes during the flood are described by statistical methods (ANOVA, correlation). Correlation matrix detecting relations between all studied characteristics of channel bars before and after the flooding was created. Causes of these changes or stability of given characteristics are analyzed in the discussion. During the September 2007 flood on Černá Opava river a number of channel bars increased, the existing accumulations particularly channel bars near bends (for example scroll bars or point bars) became larger. Channel bars got connected with the banks due to their enlargement after the flood. On the contrary, accumulations (lateral bars) placed further from bends were reduced. Faster and more complicated flow during the flood enables creation of new bars with inverse gradation.
The influence of past microclimates on the morphology and distribution of clasts is considered fo... more The influence of past microclimates on the morphology and distribution of clasts is considered for relict large-scale sorted polygons in the Krkonoše Mountains (Czech Republic). Sixty-two sorted polygons with an average length of 194 cm and an average height of 21.5 cm were measured at four sites on Mt Luční hora, at elevations of 1455 to 1555 m asl. The polygons consist of tabular clasts with a mean length of 11 cm at the borders and 5 cm in the interiors. Smaller polygons are better sorted because of the shorter distances for the clasts to reach their borders. Polygons with greater relative height are better sorted due to more intensive slope processes associated with differential frost heaving. Better sorted and more domed polygons at higher altitudes suggest more severe and longer-lasting microclimates suitable for the development of sorted polygons. The altitudinal gradient in polygon morphology and sorting suggests the dominant role of microclimate in the periglacial environment of the summit area of the Krkonoše Mountains during the Last Glacial/Holocene period. Polygon development probably involves positive feedback between morphology and frost susceptibility, driven by microclimate. The proposed method for evaluating frost sorting allows for rapid non-invasive assessment of sorting using modern methods including high-resolution remote sensing (especially terrestrial photogrammetry).
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