The freshwater dinoflagellate represent microfossils which are very rarely noted in lake deposits. In Late Holocene sediments of the Lake Młynek, the Iława Lakeland, northern Poland, we identified intense blooms of algae of the genus Palatinus. They occurred primarily in the period of strong human impact during expansion of the Monastic State of the Teutonic Order. The most amazing thing is that samples in which conventional palynological maceration has been used dinoflagellate are represented by armored vegetative forms instead of cysts. During this laboratory processes, especially acetolysis, cellulosic thecae of armored forms should be destructed. This is the second known example of acetolysis resistant thecae of modern dinoflagellate, built by substance other than cellulose. Palatinus blooms were associated probably with the hydrotechnical works made by Teutonic Knights in the catchment, which caused supply and discharge of micronutrients e.g. selenium in the basin.
This work focuses on the paleoenvironmental and palaeoclimatological history of the undisturbed core sequence of 8.6 m extracted from the Bottomless Lake (Tăul fără fund) sphagnum peat bog located in Bǎgǎu, Romania, which covers the last 8,600 years based on radiocarbon dating. By comparing results of archaeological and palaeoenvironmental investigations carried out so far in the area, results of the loss on ignition analyses and the data of the chronological analyses, it was possible to reconstruct climatic factors and anthropogenic impacts on the local environment. The undisturbed core sequence has above 86% organic matter content all along excluding the erosion horizons. Anthropogenic effects (building, woodcutting, pasturage, husbandry, farming) and changes in the local climate, vegetation, and environment increased the rate of the erosion and decreased the rate of the accumulation.
The article presents application of the new geophysical amplitude data comparison method (ADCM), resulting from integrated geophysical survey using ground-penetrating radar (GPR) and magnetometry. The ADCM was applied to recognize the horizontal and vertical stratigraphy of a Roman senatorial villa located in Santa Marina (western part of Croatian Istria). The measurements were carried out in 2017−2019 at this site, accompanied by a use of GPR and gradientometer. These two methods significantly differ from each other, but on the other hand, they are complementary to some extent. This is due to the fact that the methods register different types of underground materials. The GPR records electromagnetic waves reflected from real buried remains or boundaries between geological or archaeological layers that differ significantly in electrical properties. The magnetic method, in turn, records the anomalies of the magnetic field intensity resulting from the underground concentration of ferromagnetic minerals, hence it is ideal for searching structures filled with organic matter or burning material. However, a separate usage of these methods does not guarantee a full picture of archaeological structures that are preserved underground. Only the application of the ADCM allowed for a comparison of GPR and magnetic amplitude data reading, following which a spatial image (2D and 3D) of the preserved archaeological structures and the geological stratigraphy of the Santa Maria site were obtained.
The dynamics of climatic conditions during the Holocene in the Sumba Strait is not well known, compared with in the Indian Ocean. The aim of this paper is to identify the possible Holocene climate dynamics in Sumba Strait, eastern Indonesia by using deep-sea core sediments. A 243 cm core was taken aboard RV Baruna Jaya VIII during the Ekspedisi Widya Nusantara 2016 cruise. The core was analyzed for elemental, carbonate and organic matter content, and abundance of foraminifera. Based on geochemical and foraminifera data, we were able to identify at least six climatic changes during the Holocene in the Sumba Strait. By using the elemental ratio of terrigenous input parameter, we infer to interpret that the precipitation in the Sumba Strait during the Early Holocene was relatively higher compared with the Mid to Late Holocene.
The durability of roads is dependent on the proper screening of the variations in subsurface geological characteristics and conditions through geo-engineering investigations and good construction practices. In this study, electrical resistivity tomography (ERT) technique was used to investigate the subsurface defects and potential failures along the substrate of Etioro-Akoko highway, Ondo State, southwestern Nigeria. Results of the inverse model resistivity sections generated for the two investigated traverses showed four distinct subsurface layers. The shallow clayey topsoil, weathered layer, and partially weathered/fractured bedrock have resistivity values ranging from 4–150 ohm-m, 10–325 ohm-m, and 205–800 ohm-m, with thickness values of 0–2 m, 0.5–12.5 m, and less than few meters to > 24 m, respectively. The fresh bedrock is characterised by resistivity generally in excess of 1000 ohm-m. The bedrock mirrored gently to rapidly oscillating bedrock troughs and relatively inclined deep penetrating multiple fractures: F1–F’1, F2–F’2 and F3–F’3, with floater in-between the first two fractures. These delineated subsurface characteristic features were envisaged as potential threats to the pavement of the highway. Pavement failures in the area could be attributed to the incompetent clayey sub-base/substrate materials and the imposed stresses on the low load-bearing fractured bedrock and deep weathered troughs by heavy traffics. Anticipatory construction designs that included the use of competent sub-base materials and bridges for the failed segments and fractured zones along the highway, respectively, were recommended.
The paper presents results of studies focused on occurrence and correlation of four main horizons of Younger Loesses: Lowest Younger Loess (LMn – after Maruszczak, 2001), Lower Younger Loess (LMd), Middle Younger Loess (LMs), and Upper Younger Loess (LMg) recorded in five sections (Politów, Wąchock, Nietulisko Małe, Komorniki and Bodzechów) in the Holy Cross Mountains area. All analysed loesses were accumulated during the Vistulian Glaciation (Weichselian). The horizons were distinguished based on separating interstadial tundra soils, coupled with thermoluminescence dating, and correlated with marine oxygen-isotope stages MIS 5d−2. The Lowermost Younger Loess (LMn) covers the Nietulisko I soil complex (Jersak, 1973), developed on deposits of the Odranian Glaciation (MIS 6) and representing a forest soil of the Eemian Interglacial (MIS 5e) and the Brørup warming (MIS 5c). A thin horizon of the Oldest Younger Loess and a thin sandy horizon, both probably corresponding to the Herning cooling phase (MIS 5d) at the boundary with the Eemian Interglacial, were distinguished within this complex. Based on previously performed grain-size and heavy mineral analysis of the Upper Younger Loess (LMg) and a topographic position of the loesses in four loessy islands of diverse regional extent, accumulation of this loess in the Holy Cross Mountains area is found to have been stimulated by the western winds. The proposed model of loess accumulation takes into account the influence of the topography of the area and its geological structure.
An important source of palaeoecological and palaeoenvironmental information is intra-specimen variability of isotopic composition of mammal tooth enamel. It reflects seasonal or behavioral changes in diet and climate occurring during a life of the animal. While well-known in ungulates, in carnivorans this variability is poorly recognized. However, carnivoran remains are amongst the most numerous in the Pleistocene fossil record of terrestrial mammals, so their isotopic signature should be of particular interest. The aim of the study was to verify if enamel of a fossil cave hyena (Crocuta crocuta spelaea) and a cave bear (Ursus ingressus) records any regular inter- or intra-tooth isotopic variability. We examined intra-individual variability of δ13C and δ18O values in permanent cheek teeth enamel of fossil cave hyena and cave bear from the site of the Perspektywiczna Cave (southern Poland). We conclude that the isotopic variability of the cave hyena is low, possibly because enamel mineralization took place when the animals still relied on a uniform milk diet. Only the lowermost parts of P3 and P4 enamel record a shift toward an adult diet. In the case of the cave bear, the sequence of enamel formation records periodic isotopic changes, possibly correlating with the first seasons of the animal life.
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