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Closed depressions are characteristic elements of the loess plateau landscape. They formed by suffosive processes occurring within initial depressions in the loess cover. Detailed study were conducted in the eastern part of the Nałęczów Plateau (Lublin Upland) in one of the closed depressions located near a multicultural archaeological site. In the closed depression the Holocene soil-sediment sequence of a total thickness 1,3 m were documented. The soil-sediment sequence filling the closed depression and its bottom-forming loesses were detailed physico-chemical and micromorphological analyses as well as C-14 dating performed. This allowed to determine of postglacial litho- and pedogenesis development in the closed depression. Four major phases of Holocene sedimentation were recognized, witch were correlated with human settlement activity from Neolithic to modern times.
This work presents a use of the ¹³⁷Cs method in the reseach of soil erosion and sedimentation on the agricultural loessial land. There is an urgent need to obtain reliable quantitative data of the soil translocation in agricultural areas and to choose an effective method of soil conservation. After deposition on the land surface, ¹³⁷Cs is rapidly and strongly adsorbed by soil particles. The isotope has been present in the environment since the beginning of nuclear weapon testing and nowadays it is a part of many ecosystems. ¹³⁷Cs is therefore a valuable tracer to study soil erosion and sedimentation rate. Advantages and limitations of the method are discussed in this articles. The activity of the ¹³⁷Cs in soil samples from 4 slopes was measured by means of high-resolution gamma spectrometry and then the ¹³⁷Cs inventories for sampling points were calculated. The ¹³⁷Cs inventories relate to the erosion and deposition rates. The value of soil erosion was calculated by using the proportional model as well as the three mass balance models. The ¹³⁷Cs inventory for studied cultivated field ranges from less than 1.0 up to more than 10.0 kBq m⁻². Differences in ¹³⁷Cs inventory distribution on the terraced and unterraced slopes are clear. The results show that agricultural terraces in the study area were created alter the main period of cesium fallout and that the intensity of soil erosion in the study area appear to be significant.
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The paper presents the development of road gullies in the area covered with loess deposits. The study showed a substantial rate of the development of loess road gullies which averaged 4.5 cm⋅year–1, the minimum rate being 3 cm⋅year–1, and the maximum of 9 cm⋅year–1. The deepening of the gullies increased with exploitation time, drainage area and with longitudinal slope.
The differences between forest and agricultural loess landscapes are presented in this paper. Structure and functioning of the landscape-system were taken into account. The conclusions have been based on the results of landscape research conducted in the Nida Basin. All components of the landscape were examined, with the special focus on soils which were treated as the indicator of the landscape condition. Differences found in structure and functioning of forest and agricultural landscape open the question of making changes in the methodology of the loess landscape classification.
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