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  • Modelling patterned ground distribution in Finnish Lapland : an integration of topographical, ground and remote sensing information
  • Cold area ; Digital elevation model ; Finland ; Geographical information system ; Lapland ; Patterned ground ; Periglacial features ; Plant canopy ; Remote sensing ; Slope gradient ; Topography
  • The AA. present a new modelling approach that integrates topographical, ground and remote sensing information in predictive geomorphological mapping using generalized additive modeling (GAM). The results indicate that non-sorted patterned ground
  • is more common at lower altitudes where the ground moisture and vegetation abundance is relatively high, whereas sorted patterned ground is dominant at higher altitudes with relatively high slope angle and sparse vegetation cover. This paper confirms
  • the potential utility of remote sensing information for modelling patterned ground distribution in subarctic landscapes.
  • Formation of sorted patterned-grounds - a literature review
  • Classification ; Patterned ground ; Pedogenesis ; Periglacial features ; Soil ; Theory
  • The article presents and compares current views on the development of sorted patterned-grounds in the periglacial zone. The theories can be divided into 8 groups, which assume : 1) convection and/or circulation of the ground en masse ; 2
  • ) circulation of only fine particles of the ground ; 3) convection of pore water ; 4) heave-settlement pulsation and lateral expansion on the fine domains ; 5) cracking of the ground followed by heave-settlement pulsation and lateral expansion of the centres
  • Patterned ground in the Maritimes Provinces, Canada
  • Relict sorted patterned ground in Rostu, northernmost Sweden
  • C 14 dating ; Cold area ; Deglaciation ; Patterned ground ; Periglacial features ; Quaternary ; Spatial variation ; Stratigraphy ; Sweden
  • The objective of this study is to determine the age of active periods in relict sorted patterned ground on Rostu by studies of internal structures, spatial analysis and radiometric datings.
  • Nonsorted patterned ground on mountains in the Northern Highlands of Scotland
  • The characteristics of nonsorted patterned ground on two massifs are described and discussed with particular reference to age and mode of formation.
  • Controls on sorted patterned-ground geometry in the Swiss Alps
  • Alps (The) ; Freeze-thaw cycle ; Lithology ; Mountain ; Patterned ground ; Periglacial features ; Spatial distribution ; Switzerland
  • This paper represents results of field investigations on the distribution, morphology and structure of patterned ground formed on alpine slopes in the Swiss Alps, focusing on factors affecting the spacing of patterned ground. The study area lies
  • On patterned ground and free convection
  • The article discusses the regular system of polygons and stripes which are observed in patterned ground and which strongly suggests the occurence of one or another kind of free convection during the genesis of the pattern. It is argued
  • Relict sorted patterned ground in Lesotho
  • Cryoturbation ; Freezing ; Lesotho ; Palaeo-environment ; Patterned ground ; Periglacial features ; Permafrost ; Pleistocene
  • Relict sorted patterned ground is described from an upland interfluve on the Lesotho-South Africa border at an elevation of 3280 m a.s.l. The site comprises 2-4° slope angles. Frost penetration through the regolith is inferred to have been to 1 m
  • depth during pattern formation. Sorting is thought to have resulted from deep seasonal freezing during the depressed temperatures of the Late-Pleistocene Last Glacial Maximum. No direct evidence for permafrost is documented.
  • Observations of sorted patterned ground features, High Valley/Tangle Lakes region, Central Alaska, U.S.A. in Periglacial processes and landforms.
  • These features have been studied since 1981, and since 1982 sorted circles at six patterned ground sites in High Valley have been monitored to determine their degree of activity.
  • Forms of unusual patterned ground: examples from the Falkland Islands, South Atlantic
  • Aeolian features ; Atlantic Ocean ; Earth surface processes ; Island ; Lacustrine sediment ; Patterned ground ; Peat ; Sand ; Sediment transport ; South Atlantic Ocean
  • This paper descibes the characteristics of, and outlines the most likely origins for, three forms of unusual patterned ground observed in the Falkland Islands, South Atlantic. The features here described are not products of frost-related processes
  • Annually re-forming miniature sorted patterned ground in the high Drakensberg, Southern Africa
  • Freeze-thaw cycle ; Freezing ; High mountain ; Microrelief ; Mountain ; Patterned ground ; South Africa
  • An analysis of miniature sorted circles and polygons provides the first detailed assessment of sorted patterned ground from a southern African alpine region. Pattern dimensions and particle sorting were determined from 2 sites in the high
  • Drakensberg. Although the sorted patterns in the high Drakensberg are somewhat polygenetic in developmental origin, they are primarily frost-induced. The development of miniature sorted patterns within 5 to 6 weeks demonstrates the effect of regular freeze
  • Statistical analyses of active patterned ground occurrence in the Taillon Massif (Pyrénées, France/Spain)
  • Factor analysis ; France ; Mountain ; Multivariate analysis ; Patterned ground ; Periglacial features ; Pyrénées ; Sampling ; Spatial analysis ; Statistics
  • A novel spatial sampling strategy focusing only on fields with potential patterned ground occurrence was used. The data were examined using factor analyses (multiple correspondence analysis and hierarchical ascendant classification) blended
  • with a complementary bivariate method to associate patterned ground occurrence with 8 environmental variables. The absence of active patterned ground is associated with low elevation, glacier absence, no slopewash, a low height-distance ratio and talus fans. Zones
  • where active patterned ground features are present are divided into 3 homogeneous subzones and are mostly associated with glacier influence, a large height-distance ratio and an absence of vegetation. Their location is controlled by the presence of till
  • from different glacial sequences so that the former and current presence of glaciers favours the development of patterned ground features at the landscape scale.
  • Non-sorted patterned ground in the High Drakensberg, Southern Africa : some new data
  • Africa ; Cryopedology ; Freeze-thaw cycle ; Humid environment ; Micromorphology ; Patterned ground ; Periglacial features ; Seasonal variability ; Southern Africa
  • This paper presents empirical data on non-sorted patterned ground in the high Drakensberg. Some morphological and sedimentary characteristics for thufur and non-sorted steps are provided. The study also examines process data on ground heave activity
  • at a thufur site. Contemporary cryogenic activity at the non-sorted steps is indicative that the patterns are at least seasonally active. Soil heave measurements at the Mashai Valley thufur site support the contention that some thufur are active in the high
  • Generalized linear modelling in periglacial studies : terrain parameters and patterned ground
  • Cold area ; Finland ; Geographical information system ; Model ; Patterned ground ; Periglacial features ; Regression analysis ; Soil moisture ; Topography
  • Generalized linear models (GLM) are mathematical extensions of linear models. This paper demonstrates GLM model-building procedures step-by-step for the distribution and abundance of active patterned ground in northern Finland. Both the distribution
  • and abundance models clearly indicate an increasing activity of patterned ground with increasing soil moisture and proportion of concave topography. Activity decreases with increasing altitude. The AA. conclude that GLM techniques combined with a geographic
  • Temporal and spatial variability of soil pH in patterned-ground chronosequences : Jotunheimen, Norway
  • Cold area ; Geochemistry ; Glacier ; Little ice age ; Moraine ; Norway ; Patterned ground ; Periglacial features ; Spatial variation
  • Glacier foregrounds of Jotunheimen are characterized by the occurrence of Little Ice Age end moraines, dating to approximately the mid 18th century. Patterned-ground features occurring within chronologically established time units were studied
  • . Sorted circles and sorted nets showed significant changes in soil pH across the chronosequences. All glacier forelands showed a higher soil pH with depth in patterned ground features. The importance of microsite variability and associated disturbance
  • Development of miniature sorted patterned ground following soil erosion in East Falkland, South Atlantic
  • and indicate that in cool oceanic climates the distribution of frost-sorted patterns is controlled by the presence of bare ground on suitable regolith rather than by altitude.
  • The features have developed in the L'Antioja valley, East Falkland, following recent erosion and display many of the characteristics associated with the operation of frost-related processes in regolith materials. The patterns are currently active
  • Ground water : a parameter in determining land use pattern in Siwana region, Western Rajasthan
  • This paper aims to identify ground water potential zones and remote sensing methods to demarcate various future land use units, through geo-electrical investigation conducted in a close grid pattern around Siwana region. Secondary data are used
  • to visualise changes in the present land use pattern in future. - (PLK)
  • Post-Little Ice Age patterned ground development on two Pyrenean proglacial areas : from deglaciation to periglaciation
  • Deglaciation ; France ; Glacier retreat ; Moisture ; Mountain ; Patterned ground ; Periglacial features ; Pyrénées ; Space time
  • This study aims to observe post-Little Ice Age glacier retreat and the constitutive patterned ground development at 2 French Pyrenean glacier forelands (Taillon Glacier and Pays Baché Glacier). Periglacial feature observations are associated
  • with periods of deglaciation using aerial photos and archive files. It is highlighted that patterned ground can develop very rapidly, sometimes only 10 years after deglaciation, but patterned ground size does not systematically increase as a function
  • of the time elapsed since deglaciation. All the forms, even those developing near the Little Ice Age moraines, are active. The AA. propose that the location, activity and size of patterned ground are more probably linked to drift characteristics and local
  • Changes and spatial patterns of the differences between ground and air temperature over the Qinghai-Xizang Plateau
  • The difference between ground soil and air temperature was studied by using the data of ground and air temperature of 99 stations over the Qinghai-Xizang (Tibet) Plateau from 1960 to 2000, and its spatial distribution and time changing tendency have
  • Arctic Region ; Canada ; Cold area ; Groundwater ; Humid environment ; Patterned ground ; Periglacial features ; Permafrost
  • Preferential suprapermafrost groundwater flow was observed in deepened channels lying between raised frost mounds. In this study, the AA. examine how a type of patterned ground (sorted net) influences saturated hydraulic conductivity (k
  • ). Then, they assess the areal implications of this type of patterned ground on estimates of saturated hydraulic conductivity (k) and daily and seasonal estimates of groundwater flow (Qs) across a transitional zone (gravelly area grading into a wetland).