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EN
This paper presents the results of studies on small-scale water retention in beaver ponds and mill ponds located within the Polish Plain in the catchments of the Brda and Wda Rivers. Findings regarding small-scale retention in the Holocene were based on geological surveys and archival materials in the presence of beaver ponds and mill ponds. Traces of Holocene and contemporary beaver colonisation in this area have been documented. We collected data on the location of mill ponds during various developmental periods of the millers’ trade. The potential maximum retention in Holocene beaver ponds, contemporary beaver ponds and mill ponds was estimated and compared in both examined catchments at various stages of the development of the miller’s trade. It was established that retention in mill ponds at the peak of the development of the miller’s trade in the catchments of Brda and Wda was four times lower than the potential retention in beaver ponds during the pre-anthropogenic stage of the Holocene. Current small-scale retention in beaver ponds is variable and definitely smaller than natural and anthropogenic retention in the past. It did not compensate for the water loss associated with irrigation practices in this area.
EN
This work considers the impact of the internal alpha and beta dose rates in quartz grains obtained from sandy sediments on the results of luminescence dating. The internal dose rates reported here (ca. 0.01–0.21 Gy · ka−1) play a particularly important role, because of low (ca. 0.8–0.9 Gy · ka−1) or very low (ca. 0.4–0.6 Gy · ka−1) external dose rates. In these cases, the internal dose rates form a significant fraction of the total dose rates, often exceeding 10%. Ignoring this contribution would have made the considered luminescence ages artificially older. In our study, we measure both the internal alpha and beta contributions as the latter is usually neglected in the case of quartz. The dose rate measurements were performed using the innovative μDose system.
EN
In this work we investigate the quartz etching process using hydrofluoric acid for trapped charge dating (TCD) applications. It is done using material collected from an active sand mine in Bełchatów Nowy Świat, central Poland. Approximately 20 kg of material was collected and prepared using routine procedures that are applied in TCD laboratories. The material was sieved using 180–200 μm meshes, and the selected fraction was etched for various time intervals. Sieved samples were etched for durations from 0 min up to 180 min and measured with microscope image analysis (IA), laser diffraction (LD), and mass loss which were used to estimate the depths of etching. Our results show statistical data on how non-uniform the etching process is. We estimate this as a function of etching time from IA, LD and mass loss. In our investigation, mass loss measurements with the assumption of spherical grains correspond to the decrease of radius of ca. 0.151 ± 0.003 μm ˑ min–1. In case of LD, a rough etch depth estimation corresponds to a range 0.06–0.18 μm ˑ min–1 with median at 0.13 μm ˑ min–1. Microscope IA gives a 0.03–0.09 μm ˑ min–1 with a median at 0.05 μm ˑ min–1. Moreover, quartz grains are fractured into smaller pieces while etching. It means that assumptions that are used in etch depth estimation from mass loss are not correct. They incorrect not only because grains are not spheres but also because the number of grains is not constant. Therefore, the etch depth estimated from mass loss might be overestimated. Using microscope IA we report etch depth ranges that might be used to roughly estimate the etch depth uncertainty.
4
Content available remote Luminescence dating procedures at the Gliwice Luminescence Dating Laboratory
EN
The Gliwice Luminescence Laboratory (GLL) is a part of the Institute of Physics – Centre for Science and Education at the Silesian University of Technology, which has gradually evolved since the 1980s. To date, nearly 3500 samples have been dated using luminescence from materials such as ceramics, bricks, and sediments from archaeological and geological sites. Currently, the laboratory is equipped with four luminescence readers and three gamma spectrometers, allowing luminescence dating of approximately 300 samples annually for the needs of research projects. This article focuses on the laboratory procedures used in GLL to obtain luminescence ages. Recent improvements of the GLL's facilities and new equipment, as well as the performance spanning the Laboratory's 30 years of activity, are discussed in terms of obtained results and the involvement in national and international projects.
EN
The stratigraphy of Late Pleniglacial and Late Glacial fluvio-to-aeolian succession was investigated in two sites located at the Niemodlin Plateau, SW Poland. Lithofacial analysis was used for the reconstruction of sedimentary environments. An absolute chronology for climatic change and the resulting environmental changes were determined based on optically stimulated luminescence (OSL – nine samples) and radiocarbon (three samples) dating methods. Four phases of changes in sedimentary environments were established. The first depositional phase correlates with the Last Permafrost Maximum (24−17 ka) based on the type and size of the periglacial structures, which aggraded under continuous permafrost conditions. During 17.5−15.5 ka (upper Late Pleniglacial), a stratigraphic gap was detected, owing to a break in the deposition on the interfluve area. The second depositional phase took place during 15.5−13.5 ka. During this phase, the first part of the dune formation (Przechód site) and fluvio-aeolian cover (Siedliska site) was deposited. The sedimentary processes continued throughout the entire Bølling interstadial and Older Dryas. In the third phase (Allerød interstadial), soil formation took place. At the Siedliska site, palaeosol represented Usselo soil type, whereas at the Przechód site, there was a colluvial type of soil. The last phase (Younger Dryas) is represented by the main phase of dune formation in both sites. After the Younger Dryas, no aeolian activity was detected. High compliance with both absolute dating methods was noticed.
EN
The paper presents the results of the first OSL dating of glaciofluvial and ice-marginal lake sediments which occur between end moraines of the Słupsk Bank and the Polish coast. The sand and gravel of glaciofluvial deltas on the Słupsk Bank were deposited most likely during a period from 14.3 ±1.2 to 16.6 ±1.4 ka ago. The deposition of silty-sandy sediments of the ice-marginal lake is dated at 14.51 ±0.81 and 14.6 ±1.4 ka years. Likewise, dates ranging from 13.74 ±0.84 to 16.70 ±1.1 ka obtained from low sandy ridges, related to the southern range of the ice-marginal lake in the Gardno-Łeba Lowland, indicate the most likely timing of their deposition. It can be concluded that a short stop of the ice sheet on the Słupsk Bank took place approximately 15.2 ka ago, which could be correlated with the position of the ice sheet front in central Skåne and in northern Lithuania at that time. Older and younger results were also obtained, except the dates mentioned above. The older ages show little sunlight exposure of sediments during their deposition. The younger dates indicate a marine origin of the sediments and show that some parts of glaciofluvial sediments were redeposited and exposed to sunlight at a later stage, most probably when dead-ice blocks were melting.
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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