Else Kolstrup’s research while affiliated with Uppsala University and other places

The remains of a hunting site dated to 15 000 years ago, captured in an ice wedge, included woolly rhinoceros, horse and arctic fox. Also present were 30 flint plaquettes with curvy feminine outlines. The authors show that these unworn flint profiles can be assigned to a canon of Magdalenian art that extends over much of northern Europe.

Data from different disciplines are integrated and used to propose an alternative hypothesis regarding the Upper Weichselian environmental developments in the central Scandinavian mountains. This hypothesis, which tries to integrate new and controversial finds and explain them in a new light, is far from proven and needs much further research. It is proposed that parts of the mountains have been glacio-isostatically more depressed than previously thought and that the glacial dynamics could have been much more pronounced than traditionally assumed. As a consequence, it is proposed that Baltic-Bothnian water crossed temporarily ice-free areas with low-altitude thresholds across the Scandinavian mountain range, sporadically allowing drainage towards the Atlantic Sea, and even that Atlantic water could temporarily have entered into Sweden from the west. Such land-water scenarios could have resulted in a water transport system that steered floating tree seeds and sprouts, transported by rivers from central Europe and/or by seawater from the Atlantic, into the mountain range. There, high isostatic rebound rates during early deglaciation phases could quickly have made coastal areas become land, allowing plants to start their life cycle almost immediately.

Movements of 24 cm large globes and cuboids of granite, concrete and wood were recorded during four and a half years. The objects were buried at three different depths in well-sorted sand in a natural cool temperate environment. All objects moved during the experiment and at the end most wood objects, which had a relatively low thermal conductivity had moved up, and the granite and concrete objects with higher thermal conductivities had sunk a little or remained almost in place. Also the soil surface moved and its final height was up to 1 cm above that at the start. The movements of the objects started within a few hours after temperature shifts around 0 °C with the granite reacting more readily than the wood. It is hypothesized that the movements are related to the thermal properties of the objects and the soil. The experiment was done in parallel with an experiment in clayey silt and the net results in sand show clear parallels to the movements of similar objects in the silt. It is concluded that the material and shape of the object are more important to movements than whether they are embedded in sand or silty clay.Research Highlights► Granite, concrete and wood objects in sand responded quickly to shallow frost. ► Granite, with its higher thermal conductivity, responded more readily than wood. ► After more than 4 years wood objects had moved up and granite objects down. ► Strong parallels were found in movements of similar objects in sand and silt. ► Hypothesis: H2O vapour moves from air and soil and accumulates as ice in topsoil.

We recorded movements of 24 cm large globes and cuboids made of granite, concrete and wood buried at three different depths in silty soil, in a cool temperate environment during four and a half years. We also monitored 4-hourly soil moisture and air and ground temperature. All objects heaved during freezing and fell back during thawing, and some sank during the summers. Freeze–thaw in a very shallow surface layer may result in heave of objects due partly to sediment infill in unfrozen soils beneath the objects. The net result was sinking of some of the granite and concrete objects and rise of wooden ones. The recorded object movements, in relation to the thermal properties and specific gravity of the objects and the embedding soil, show that an (almost) isodiametric object tends to sink or remain in place if its thermal conductivity and density exceed those of the surrounding soil, and to rise if the reverse is the case.

Solifluction movement rates from 1952 to 2008 for the Abisko region, northern Sweden, have been compiled and analysed through correlation tests and multiple regression. The temporal analysis is based on two datasets (Lobe11 & gridAB and Line B) from Kärkevagge. The dataset Lobe11 & gridAB show a strong correlation between movement rates and mean annual air temperature (MAAT) and MAAT is also identified as one of the significant contributing parameters in the multiple regression model. No significant correlations were found for the Line B dataset. The spatial analysis indicates generally higher movement rates in the western part of the region and at lower altitudes mainly between 700 and 900 m a.s.l., but the spatial variability is high. To reduce the influence of the temporal variation the data for the correlation tests of the spatial variations were divided into two parts: 1957 to 1980 and 1981 to 2008. The correlation analysis of the dataset 1957 to 1980 shows a significant negative correlation between annual average movement rates and permafrost probability and altitude. The dataset 1981 to 2008 shows a positive correlation between movement rates and wetness index. It is concluded that movement rates may increase with higher MAAT in the western part of the region (Kärkevagge), the spatial variability of movement rates within the region is very high and that altitude (and/or permafrost) together with wetness index are the main controls on the regional spatial variation. The study highlights the limitations in establishing statistical relationships between movement rates and climate using data from different field empirical studies.

A new, detailed geomorphological mapping system is tested at different scales for presentation of landscape configuration and interpretation of landscape development of a formerly glaciated area near Mora in central Sweden. The geomorphological maps are based on fieldwork supported by aerial photographs. The area contains landforms created by mass movement, glacial, glaciofluvial, fluvial, lacustrine, aeolian and anthropogenic processes. In addition, geomorphological effects of isostatic uplift, which has caused a c. 220 m rise of the former Ancylus lake shoreline in the area since the deglaciation, can be seen. The new system is tested at scales 1:5000, 1:25,000 and 1:50,000 using the same legend. At the largest scale information on morphography/morphometry, lithology, and hydrography are included in the map as are details on polygenetic origins of landforms. With each step from the 1:5000 to the 1:50,000 scale some generalisation is needed at the cost of descriptive detail. In turn, with smaller scale, the general overview of the area increases and the impression from the map gradually becomes more dominated by genesis. The emphasis of the map thus changes from a presentation with a high level of descriptive information at the largest scale to a more interpretative overview at smaller scales. The scale transformation shows that the geomorphological presentation of the landscape is a function of both the landscape hierarchy and the geomorphological context within an area. The use of the new geomorphological mapping system at the three scales shows that the tested mapping legend can be used without modification from one scale to another. This is mainly because the geomorphological information parameters are separated in the legend, and that explanatory information is gained from combinations of them. The possibility to apply the same legend at different scales for an area facilitates the choice of an appropriate mapping scale for specific purposes and applications. The new mapping system also has the advantage that the data can be easily transformed into a GIS ESRI geodatabase containing the same “raw-data” as the original map. The differences of information at the different scales illustrate problems that are also relevant for use and presentation of geomorphological data in a GIS and three examples of scale problems in relation to GIS data handling are outlined.

A pollen diagram from a site in the Esbjerg area, western Denmark, is used for reconstruction of the Holocene vegetational and environmental history there. During the Atlantic there was a parallel development of the landscape to that of other areas in Jylland (Jutland). From the late Neolithic onwards the development took its own course related to the approaching North Sea, which periodically inundated parts of the Esbjerg area. The record reflects landscape development in a formerly marine valley where sediments seem to be missing from parts of the Bronze Age and the early Iron Age. Consequently the landscape development during these times is only reflected in glimpses in the vegetation record, which shows gradually more open woodland and increasing human impact. During the late part of the Iron Age, Viking period and Middle Ages, the woodland was diverse in taxa but became increasingly open, finally reaching a stage during which there may have been too little wood even for daily use. At the same time the use of the land intensified. During the Sub-Atlantic, the Esbjerg area offered good natural resources with extensive grazing areas in the marine marshes in addition to good possibilities for farming and use of the woodland on higher ground, but devastating floods occurred.

Kolstrup, E. 2007 (January): Lateglacial older and younger coversand in northwest Europe: chronology and relation to climate and vegetation. Boreas , Vol. 36, pp. 65–75. Oslo. ISSN 0300–9483. Dutch, Belgian, German and Danish Lateglacial localities with both coversand and well‐dated organic deposits are used to relate older and younger coversand development to changes in climate and vegetation. The number of well‐dated coversand sequences in northwest Europe is low, but it appears that the transition from older to younger coversand was asynchronous and spanned Bølling sensu stricto to late Allerød, so there is no clear single cause for the change in grain‐size composition of the sediment. Aeolian activity took place during all parts of the Lateglacial and seems to have continued well into the Holocene. The effect of changing temperatures is mainly reflected indirectly as periods with denser vegetation, especially forest, that led to reduced coversand net‐accumulation. The outline proposes that the lithostratigraphic position of a peat layer cannot be used as an Allerød marker because even a well‐developed peat layer within coversands may differ in age from one area to the next. The combined coversand and vegetation development shows that local conditions were important for the accumulation and preservation of sediments.

The chronology of two adjacent Danish Lateglacial sedimentary sequences with well-developed layering of alternating aeolian sand and organic matter has been investigated using both Optically Stimulated Luminescence (OSL) and Accelerator Mass Spectrometry (14C). Both sites are known to cover at least the period Bølling to Younger Dryas, with the so-called older and younger coversand types present at both localities. Typical overall uncertainties with the OSL data are about two to five times those of the 14C ages, but both data sets contain clear outliers. When these are excluded, OSL ages appear to be systematically slightly younger than the 14C ages, by about 10%; possible reasons for this are discussed. The investigation stresses the importance of making several age estimates from any single locality. The older coversand type makes up the pre-Bølling and most, or possibly all, of the Bølling (which also has the highest net accumulation rate). Deposits of the younger coversand type are dominant in layers younger than the Bølling.