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EN
Forested mountain slopes can be simultaneously affected by soil creep and landslide activity, both of which cause the tilting of tree stems, with the result that their dendrochronological record of tree-ring eccentricity and compression wood is potentially similar. There is a need to identify similarities and differences in these records and thus our research aimed to compare patterns of eccentricity and compression wood developed by trees under the impact of soil creep and landslides. We sampled trees growing on a landslide and creeping slopes in the Kamienne Mts., with 21 Norway spruce trees were sampled on each site. We found several main differences between the dendrochronological record of landslide activity and soil creep. On the landslide we found larger number of dendrochronological events, stronger and more variable eccentricity and a similar number of upslope and downslope events. On creeping slopes, upslope eccentricity events predominate, and the number of eccentricity events dated in all trees increases in time. We also compared the utility of eccentricity and compression wood for dating mass movements. They differ in their sensitivity to stem tilting. Thus, in analyses of landslide activity and soil creep activity, it is recommended to include both wood anatomy features.
EN
In the Odra and Osobłoga River valleys in the vicinity of the town of Krapkowice, a system of morphological levels is present which is exceptionally extensive compared to other such systems in southern Poland. The extent, origins and chronology of these levels have been the subject of many controversies. In the light of current research, the terraces, which are situated on average 14.5-13, 12-10, 8-6, 6-4 and 3-1 metres above the river level, were formed in the post-Wartanian interval. The main factor driving their development was erosion, which compensated for the effects of large-scale aggradation that had occurred during the anaglacial phase of the Odranian Glaciation (MIS 8) dated to 261 ±15 ka. The impact of climatic conditions on the trends towards fluvial erosion or accumulation was only of secondary importance. According to OSL dating, successive phases of vertical stabilisation of the valley floor occurred ~118.8 ±8.3, 87.7 ±5.7 and 42.0 ±2.0 ka. In the meantime, erosion intensified, which resulted in the formation of lower terrace levels. During the climatic minimum of the Upper Plenivistulian (21.5 ±1.5 ka), under conditions of the delivery of sheet-wash-generated sediment, the aggradation of distal reaches of the Odra River valley was locally marked. During the Late Vistulian and Holocene, erosive tendencies continued, which were reflected by the fact that the surfaces of subsequent inset alluvial fills were situated ever lower. In the light of dating results, it can be concluded that during the colder periods correlated with the Rederstall Stadial (MIS 5b) and with the Hasselo Stadial (MIS 3), a braided river was present in the river valleys examined, which was most probably accompanied by permafrost. During the Eemian Interglacial (MIS 5e), during the Late Vistulian Interstadials and in the Holocene, it was a meandering river.
EN
The main aim of this study was the reconstruction of the environmental changes (identifiable at this stage of research) resulting from large-scale charcoal production for the needs of historical water-powered metallurgy in selected sites in the Mała Panew basin. The identification of the remains of charcoal hearths was carried out by analysing shaded relief models. Shaded relief models were created from data from Airborne Laser Scanning (LIDAR). In order to verify the charcoal hearth remains identified in digital images, ground proofing was carried out. The charcoal hearth remains were subjected to sampling. Fragments of charcoal were extracted from the samples, which were then sent for analysis to identify tree species. In order to determine the age of chosen charcoal hearth remains, 10 charcoal pieces were submitted for radiocarbon dating. The following taxa were identified: Scots pine (Pinus sylvestris), alder (Alnus sp.), birch (Betula sp.), oak (Quercus sp.), Norway spruce / larch (Picea abies / Larix sp.), Silver fir (cf. Abies alba) and ash (Fraxinus excelsior). The taxa identified are dominated by Scots pine (56%). This research demonstrates that valuable wood of deciduous species might have been overex-ploited at the initial stage of metallurgical production and very quickly exhausted, being replaced by fast-growing coniferous species. The excessive exploitation of the forests might have had negative environmental effects such as the transformation/modification of the species composition of the forest cover, significant deforestation of exploited areas, intensification of floods or the initiation of aeolian transport of sands. All the charcoal hearth remains investigated date to the period from 1677 to 1957 AD.
EN
We have compared maps of landslide activity and hazard, developed with the use of two different dendrochronological indicators: tree-ring eccentricity and reaction (compression) wood. The maps were prepared based on 125 Norway spruce (Picea abies L. Karst.) trees growing at 44 sampling points, distributed over an area of 3.75 km2. In general, the two maps show similar patterns of landslide activity. However, tree-ring eccentricity yielded a greater number of dated events (246) compared to compression wood (129). Besides the differences in the absolute values of dating results, the general landslide activity and hazard zonation based on both disturbances are similar. Both growth disturbances develop as a result of stem tilting. Eccentricity develops after slight tilting, while compression wood is developed when tilting is more significant. Because of the differences in the strength of disturbing factors, which cause the development of compression wood and growth eccentricity, the best approach would be to combine the results of dating obtained from the two methods. The dendrochronological analysis of tree growth disturbances (eccentric growth and compression wood) is a promising approach for determining landslide hazards in forested mountain areas and can be applied in spatial management.
EN
Loess areas used for agriculture are susceptible to soil erosion. The intensive process of soil erosion in Polish loess areas began with the onset of the Neolithic and has continued intermittently until today. This work presents the results of soil erosion from simultaneous use of the 137Cs and 210Pbex methods on an agricultural field located on loess slope. Moreover, to establish the age of accumulated sediment connected with water slope erosion, OSL dating, selected physicochemical and micromorphological analyses were applied. The reference values of the 137Cs and 210Pbex fallout for the studied site (Biedrzykowice, the Proszowice Plateau, Małopolska Upland) equal 2627 (45% connected with Chernobyl) and 4835 Bq·m–2, respectively. The results of the 137Cs and 210Pbex inventories measured for the agricultural field range from 730 to 7911 and from 1615 to 11136 Bq·m–2, respectively. The mean soil erosion is about 2.1 kg·m–2·a–1 (about 1.4 mm·a–1). The accumulation of the colluvial sediments started in the Neolithic and drastically increased in the Middle Ages. The examined gully catchment in Biedrzykowice has probably developed quite rapidly as a result of increased erosion. This resulted in the abandonment of this area as farmland and, consequently, in the minimization of water erosion on the slope due to the entrance of woody vegetation in this area. Erosion processes were highly intensified during the last 70 years as a result of deforestation after World War II and intensive agricultural reuse of this area after a break, as indicated by isotope measurements and dendrochronology.
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