11 research outputs found

    Geologiczne i geomorfologiczne uwarunkowania lokalizacji dawnych młynów wodnych nad dolną Liswartą

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    The location of the former water mills was studied on the lower Liswarta River on the Wieluń Upland. Fieldworks were supplemented with an analysis of the digital elevation model, detailed geological maps and historical topographic maps. The location of seven water mills was analysed with reference to local geological structures and limestone outcrops, as well as to the relief features of the Liswarta valley. Studies showed that water mills had been located usually in places, where the slope of the river channel increases. Such conditions correspond to mixed bedrock-alluvial segments of the river channel and narrow parts of the valley. There were no millponds on the lower reaches of the Liswarta River – only low weirs in the river channel were built. River discharge proved to be enough for working mills

    Anthropogenic causes of wetland loss and degradation in the lower Kłodnica valley (southern Poland)

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    Loss and degradation of wetlands is now one of the most important environmental issues on a global scale. Previous research based on analyses of cartographic materials allow for quantification of changes in wetland area in recent centuries. The results of lithological research of peat cores, reported in this publication, have established that the processes of anthropogenic loss of wetlands can be much older and in the Kłodnica valley were initiated in the first millennium BC. As a result of increased mineral sedimentation accompanying soil erosion some peatlands have been fossilized whilst the area of others has been reduced. In total, the surface area of peat-forming wetlands in the bottom of the Kłodnica valley decreased by over 60% between the time of the Lusatian Culture settlement and the Middle Ages. Post-peatland habitats are recently used for agricultural or colonized by non-peat forming vegetation. These processes have played a more important role in the degradation of peatland ecosystems than the direct human impact in historic times. Changes in hydrographic networks, land drainage and regulation of water levels in rivers and canals in the last century have contributed to further reducing the wetland areas by almost 50% compared to the 1880s. These processes, however, have mainly affected ephemeral non-peat forming wetlands

    Cadomian protolith ages of exotic mega blocks from Bugaj and Andrychów (Western outer Carpathians, Poland) and their palaeogeographic significance

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    This study presents the first zircon U-Pb LA-MC-ICP-MS ages and whole-rock Rb/Sr and Sm/Nd data from exotic blocks (Bugaj and Andrychów) from the Western Outer Carpathians (WOC) flysch. The CL images of the zircon crystals from both samples reveal typical magmatic textures characterized by a well-defined concentric and oscillatory growth zoning. A concordia age 580.1 ± 6.0 Ma of the zircons from the Bugaj sample is considered to represent the crystallization age of this granite. The zircon crystals from the Andrychów orthogneiss yield an age of 542 ± 21 Ma, in-terpreted as the uppermost Proterozoic, magmatic crystallization age of the granitoid protholith. The initial (at ca. 580 Ma) 87Sr/86Sr ratios of the Bugaj granitoids (0.72997 and 0.72874) are highly radio-genic, pointing to the assimilation of an older, possibly strongly Rb enriched source to the Bugaj melt. The Nd isotope systematics (εNd580 –1.4 and 0.4) also point to a significant contribution of such a dis-tinct mantle source. On the basis of the sequence of magmatic events obtained from U-Pb zircon ages, we suggest that exotic mega blocks deposited to the WOC basins were related to the Brunovistulicum Terrane. They belong to the group of Vendian/Cambrian granitoids representing the latest, post-tectonic expression of the Cadomian cycle

    Human-planted alder trees as a protection against debris flows (a dendrochronological study from the Moxi Basin, Southwestern China)

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    Large debris flows have destroyed the infrastructure and caused the death of people living in the Moxi Basin (Sichuan Province, Southwestern China). Inhabitants of the Moxi Basin live on the flat surfaces of debris-flow fans, which are also attractive for farming. During the monsoon season debris flows are being formed above the fans. Debris flows can destroy the houses of any people liv-ing within the fan surfaces. In order to prevent the adverse effects of flows, people plant alder trees (Alnus nepalensis) at the mouths of debris flow gullies running above debris flow fans. Alders are able to capture the debris transported during flow events. Trees are well adapted to surviving in con-ditions of environmental stress connected with abrupt transport and deposition of sediment from de-bris flows. Numerous wounds, tilting and bending of alder trees caused by debris flows only very rarely cause the death of trees. By dating scars and dating the time of alder tilting (through the analy-sis of annual rings), we have determined the frequency of debris flows occurring at the mouth of the Daozhao valley. In 1980-2012 within the studied debris-flow fan and the Daozhao gully, 2 large de-bris flow events occurred (1996, 2005) and some smaller events were probably recorded every 2-3 years

    Geneza i zasięg vistuliańskiego zespołu terasowego Odry-Osobłogi pod Krapkowicami

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    The system of morphological levels occurs on the slopes of the Odra and Osobłoga valleys in the vicinity of Krapkowice, southern Poland. Their genesis, range and age have been the subject of lively scientific discussion since the 1930s. Geomorphological analysis confirmed the fluvial origin of these flats. The use of LIDAR data allowed for precise height determination and revision of the range of indivi-dual river terraces, which rise above the valley bottom to a height of about 166 m a.s.l. (more or less 6 m above the Osobłoga/Odra channel), 168 m a.s.l. (8 m), 172 m a.s.l. (12 m), 174 m a.s.l. (14 m) and 181 m a.s.l. (21 m) res-pectively. The dating of sediments building the terrace elevated to 172 m a.s.l. using the OSL-SAR method gave a result of 87.7 ± 5.7 ka (GdTL-2820) indicating that it originated from the last cold stage of the Pleistocene. The ter-race surface was shaped by a sand-gravel braided river, which has developed on the substratum of the alluvium do-cumenting the period of intense valley-floor aggradation

    Współczesne wykorzystanie przez bobra europejskiego Castor fiber antropogenicznie przekształconych dolin rzecznych (przykłady z Równiny Opolskiej i Wyżyny Woźnicko-Wieluńskiej)

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    W pracy przedstawiono typowe przypadki konstruktorskiej działalności bobrów w dolinach Małej Panwi i Liswarty oraz ich dopływów. Przeprowadzone badania wskazują, że bobry chętniej zasiedlają małe rzeki 3-4 rzędu niż rzeki główne. Najliczniejsze ślady działalności bobrów zaobserwowano na zalesionych odcinkach dolin Leńcy i Olszynki, gdzie gryzonie przekształciły 28-35% długości koryt rzecznych. Interesującym, niemal symbolicznym przypadkiem jest „naprawa” przez bobry grobli ziemnych starych stawów antropogenicznych i utworzenie w ich miejscu stawów bobrowych

    Historical water-powered ferrous metallurgy reconstructed from tree-rings and lacustrine deposits (Mała Panew basin, southern Poland)

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    According to historical sources in the basin of Mała Panew River there were at least 56 water- powered iron smelters from 14th–19th century. Now only two metallurgy plants work in the area. Many of the former smelting settlements ceased to exist. Historical data on the smelting industry in the area are often scarce. The aim of the study was to reconstruct the history of ferrous metallurgy from (1) the remains of wooden historical buildings, (2) remains of charcoal kilns and (3) deposits from former smelter pond. Results show that Regolowiec smelting settlement existed already in the 17th century (at least several decades earlier than historical written sources suggest) and was later repaired after destruction caused probably by floods. Charcoal used for iron smelting in the ironworks in Brusiek on the Mała Panew River was burnt at the turn of the 18th century. This is in accordance with historical sources indicating particular prosperity of the metallurgy in that period. Upstream of the ironworks in Brusiek in the first half of the 17th century a large pond existed flooding the floor of the Mała Panew valley. Study has shown that the pond was at least 100 years older than historical sources have indicated

    Erosion and accumulation phases during the last glacial-interglacial cycle : a case study of the terrace system of the Odra and Osobłoga rivers (southern Poland)

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    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
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