Showing papers in "Geografisk Tidsskrift-danish Journal of Geography in 1993"
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38 citations
TL;DR: Christiansen et al. as discussed by the authors investigated the geomorphology of the Zackenberg area with the purpose of establishing a geomorphological map of a 260 km2 area around the planned research station.
Abstract: Christiansen, Hanne Hvidtfeldt & Ole Humlum: Glacial History and Periglacial Landforms of the Zackenberg area, Northeast Greenland: Preliminary results. Geografisk Tidsskrift 93:19–29. Copenhagen 1993. The geomorphology of the Zackenberg area has been investigated with the purpose of establishing a geomorphological map of a 260 km2 area around the planned research station. Production of a large digital three-dimensional elevation model, based on the use of a multi-model photogrammetric method, has been the basis for a GIS database and a topographical map (1:50,000) covering the investigation area. Both glacial and periglacial landforms have been mapped and a preliminary Late Weichselian glacial history of the Zackenberg area reconstructed. A monitoring of 11 selected test field sites representing climatically sensitive land elements has been established, enabling the registration of even minor short-term variations in the geomorphic processes.
29 citations
TL;DR: Hasholt et al. as mentioned in this paper performed field investigations of runoff and sediment transport in the proglacial area of the Mitdluagkat Glacier drainage basin in September 1992, showing that the formation of frazil ice and anchor ice caused increased sediment transport.
Abstract: Hasholt, Bent: Late Autumn Runoff and Sediment Transport in a Proglacial Drainage System, Sermilik, East Greenland. Geografisk Tidsskrift 93:1–5. Copenhagen 1993. Field investigations of runoff and sediment transport were carried out in the proglacial area of the Mitdluagkat Glacier drainage basin in September 1992. Runoff in the proglacial stream was 32 l/s/km2. Runofffrom the northern flank of the glacier at the outlet of Lake Kugssuag was 14 l/s/km2. Mean daily sediment transport was 17 t/d in the proglacial valley and 0.2 t/d at the outlet of the lake. It was clearly demonstrated that the formation of frazil ice and anchor ice caused increased sediment transport, dominating the total load of the proglacial stream during the measuring period 2/9–19/9.
16 citations
TL;DR: Fredskild et al. as discussed by the authors investigated the role of caribou grazing in the formation of the West Greenland greens and found that 25% of the time during summer, peaking at 78% in post-calving period.
Abstract: Fredskild, Bent & Sune Holt: The West Greenland “Greens”—Favourite Caribou Summer Grazing Areas and Late Holocene Climatic Changes. Geografisk Tidsskrift 93:30–38. Copenhagen 1993. Though covering less than 2% of the area around Kangerlussuaq, Midwest Greenland, small “greens” of non-flowering Poa pratensis are used as feeding sites by caribou, 25% of the time during summer, peaking at 78% in the post-calving period. Analyses of pollen content and chemical composition in soil profiles confirm the hypothesis of their formation being a result of grazing. The original vegetation types were Salix glauca scrubs or grassy Betula nana heaths. Indications of earlier grazing periods are seen in some profiles. Besides, a climatically caused change to more humid vegetation is seen in all profiles. This event has been 14C dated at 1690 ± 75 B P. in one profile. Due to a recent pronounced decline in the caribou population, the greens are now changing with Poa pratensis flowering vigorously as a result of little or no ...
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TL;DR: Jacobsen et al. as discussed by the authors presented an approach for obtaining reflectance factors and surface albedo on a glaciated surface in a high relief environment combining a digital elevation model and SPOT HRV satellite data.
Abstract: Jacobsen, Anne, Allan R. Carstensen & John Kamper: Mapping of satellite derived surface albedo on the Mitdluagkat Glacier, Eastern Greenland, using a digital elevation model and SPOT HRV data. Geografisk Tidsskrift 93:6–18. Copenhagen 1993. An approach for obtaining reflectance factors and surface albedo on a glaciated surface in a high relief environment combining a digital elevation model and SPOT HRV satellite data is presented. The methodology has been applied on the Mitdluagkat Glacier, Ammassalik, Eastern Greenland. Correction of reflectance factors with respect to solar incidence angle permits classification of different glacial metamorphic fades favourably compared with published data on field measurements from other glaciated regions. Development of surface albedo on reflectance factors corrected for solar incidence angle enables spatial analysis of the glaciated surface thus providing mapping of local climate induced surface features and the spatial distribution of ablation and accumulation zone...
7 citations
TL;DR: Rasch et al. as discussed by the authors examined variations in cusp spacings of beach cusp systems, and the conclusion is that the apparent regularity of the spacings is not always real.
Abstract: Rasch, Morten, Jorgen Nielsen & Niels Nielsen: Variations of Spacings between Beach Cusps discussed in relation to Edge Wave Theory. Geografisk Tidsskrift 93:49–55. Copenhagen 1993. Variations in cusp spacings of beach cusp systems have been examined, and the conclusion is that the apparent regularity of the spacings is not always real. Established edge wave theory predicts equal cusp spacings, and accordingly, the theory needs to be improved or alternative theories accepted. Field measurements of beach cusp formation under reflective morphodynamic conditions confirmed that established edge wave theory was not always capable of explaining beach cusp formation. The beach cusps grew from small irregularly spaced mounds, and the regularity of the cusp spacings seemed to increase during beach cusp development. Correlation between observed average cusp spacing and the average cusp spacing predicted on the basis of edge wave theory might suggest that edge waves were the initiating mechanism causing beach cusp d...
6 citations
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TL;DR: Krogh et al. as mentioned in this paper investigated the major soil types in a village in Northern Burkina Faso and found that the soil is inherently low in organic matter, the level of macro-nutrients is low, soil structure is weak or unfavourable, probably due to a combination of natural and human factors.
Abstract: Krogh, Lars: The Major Soils of a Village in Northern Burkina Faso. Geografisk Tidsskrift 93:90–100. Copenhagen 1993. In the Oudalan Province of Sahelian Northern Burkina Faso soil investigations have been carried out in order to evaluate the sustainability of millet production with emphasis on the dynamics of soil fertility. Some results of pedological investigations carried out in 1990 are included. Three commonly occurring soil types in a village territory are examined and their genesis and fertility discussed. Analyses show that the soils are inherently low in organic matter. The level of macro-nutrients is low, soil structure is weak or unfavourable: all probably due to a combination of natural and human factors. Crop yields are generally low and cannot be raised without more intensive cultivation.
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TL;DR: Christiansen et al. as mentioned in this paper used thermoluminescence (TL) dating and geographical information system (GIS) analysis to date and trace the source area of the sediment in the Bjergsted cone.
Abstract: Christiansen, Hanne Hvidtfeldt: Late Weichselian Periglacial Landforms in the Bjergsted area, north-western Zealand. Denmark. Geografisk Tidsskrift 93:39–48. Copenhagen 1993. Detailed geomorphological investigations in the central part of the Bjergsted landsystem have revealed the existence of different Late Weichselian periglacial landelements. A large alluvial cone, named the Bjergsted cone, with ice-wedge casts and sediment-structures indicating dead-ice melting has been investigated. Different methods, such as thermoluminescence (TL) dating and geographical information system (GIS) analysis, have been used in order to date and trace the source area of the sediment in the Bjergsted cone. Several dry valleys and niches caused by nivation as well as windpolished boulders have also been found in the Bjergsted area.
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TL;DR: Hasager et al. as mentioned in this paper presented a method for satellite mapping of evapotranspiration based on the canopy resistance theory, which produced better defined differences between fields than a model based on net radiation, air temperature, and satellite-derived surface temperature.
Abstract: Hasager, Charlotte Bay: Satellite remote sensing as a tool for spatial evapotranspiration estimation in vegetated areas. Geografisk Tidsskrift 93:56–62. Copenhagen 1993. The present paper outlines and tests a method for satellite mapping of evapotranspiration based on the canopy resistance theory. The dataset used for the analysis was obtained during a field campaign conducted in an agricultural region east of Viborg, Jutland, April to August 1990. Scale between low-resolution NOAA satellite images and ground truth values were tested with a single high-resolution Landsat satellite image. The results are found to be in accordance with field observations. In accordance with canopy resistance theory, a simple empirical algorithm was found effective for evapotranspiration estimation using satellite data. This approach also produced better defined differences between fields than a model based on net radiation, air temperature, and satellite-derived surface temperature.
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TL;DR: Morch et al. as discussed by the authors studied the settlement pattern of part of Apulia, southern Italy, where the population is concentrated in large rural towns, and the main locational factors are suggested as being related to natural resources.
Abstract: Morch, Henning: Settlement Location in the Murge, Apulia, Southern Italy. Geografisk Tidsskrift 93:69–79. Copenhagen 1993. This is a study of the settlement pattern of part of Apulia, southern Italy, where the population is concentrated in large rural towns. As the topography is very gentle, other factors determining the location of settlement have been suggested in the past. In this article, the main locational factors are suggested as being related to natural resources. This hypothesis is supported statistically (G-test).
TL;DR: Raagaard et al. as mentioned in this paper described the change in the crop composition around 1970 and the changes are described to show the types of innovation and the traditional agricultural systems have not prevented the changes, but around 1990 the development reached a certain limit.
Abstract: Raagaard, Svend: Ecology and Agricultural Development in Four Villages of Central Karnataka. Geografisk Tidsskrift 93:63–68. Copenhagen 1993. In Central Karnataka the farmers have for a long time adjusted their farming methods and strategy to; ecological conditions, seasonal distribution and variability of precipitation and soils. This study concerns four villages. The crop composition around 1970 and the changes are described to show the types of innovation. New fast maturing varieties of food grains have been accepted everywhere, and the use of chemical fertilizers and pesticides has increased dramatically. A shift to cash crop, especially cotton, has occurred in many places. Also described is how the traditional agricultural systems have been adjusted to the innovations. So far they have not prevented the changes, but around 1990 it seems that the development reached a certain limit. If agricultural production has to keep up with the population growth, new practices, strategies and crops have to be ide...