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EN
This paper is a summary of the results of research on the accumulation conditions of the Upper Younger Loess (LMg) in Poland and Bug loess (bg) in Ukraine from the maximum stage (MIS 2) of the Vistulian (Weichselian) Glaciation in central and eastern Europe. These studies included an analysis of the morphological (topographic) situation of the loess cover, its grain size and heavy mineral composition, the preserved structures of loess sedimentation as well as mollusc and pollen analyses of this loess. They revealed that the accumulation of Upper Younger Loess (UYL) might have been more dependent on the prevailing moisture conditions than previously thought. These conditions could have been caused by cold air masses from an ice sheet and warm air masses from the Mediterranean Sea and Atlantic coming together in the Carpathians and the Holy Cross Mountains and favouring the formation of dust storms and precipitation. In this process, a loading of loess dust (formed from local rocks weathering in periglacial conditions) by atmospheric moisture particles was especially significant. The moist substrate not only favoured the periodic development of vegetation and molluscs but also enabled the interception of dust and the accumulation of an increasingly thick loess cover. Westerly and south-westerly winds predominated in the UYL as indicated by the topographic position of loess patches and the mineral composition of the studied loess. Periodically an increased air circulation from the east and northeast occurred.
EN
The Curonian Spit is one of the largest Holocene sand accumulation forms, stretching along the Baltic Sea coast and belonging to the Baltic sand belt. This article deals with the dynamics of the Curonian Spit dunes in the context of global climate change. Investigations were carried out in the environs of two high dunes (Parnidis Dune and Naglis Dune) over a period of 10 years (2003-2014). Levelling of cross-sections was performed using modern geodesic devices. Wind velocities and directions were measured at meteorological stations of Klaipeda and Nida. The wind regime (number of days with winds >15 m/s) was almost at the multiannual average during the study period. Sand moisture was measured in both dunes studied, and groundwater level was measured in the environs of the Naglis Dune by using ground penetrating radar (GPR). The Naglis Dune experienced a more significant lowering (by 4-6 m) compared with the Parnidis Dune over the study period, while sand deficit was greater in the Parnidis Dune (~10,000 m3). Compared with other European sand dune systems, the Curonian Spit dunes have undergone strong degradation. The article highlights possible degradation reasons and indicates the necessity of additional investigations. Only long-term investigations can contribute to disclosing the main processes both as natural background and due to anthropogenic activities, and the devising of protection measures.
EN
Presented are the results of research into the fluvio-aeolian sedimentary succession at the site of Postolin in the Żmigród Basin, southwest Poland. Based on lithofacies analysis, textural analysis, Thermoluminescence and Infrared-Optical Stimulated Luminescence dating and GIS analysis, three lithofacies units were recognised and their stratigraphic succession identified: 1) the lower unit was deposited during the Pleni-Weichselian within a sand-bed braided river functioning under permafrost conditions within the central part of the alluvial fan; 2) the middle unit is the result of aeolian deposition and fluvial redeposition on the surface of the fan during long-term permafrost and progressive decrease of humidity of the climate at the turn of the Pleni to the Late Weichselian; 3) the upper unit accumulated following the development of longitudinal dunes at the turn of the Late Weichselian to the Holocene; the development of dunes was interrupted twice by the form being stabilised by vegetation and soil development.
PL
Artykuł dotyczy badań relacji człowiek–środowisko na przykładzie osady kultury mogiłowej ze środkowej epoki brązu, którą odkryto na obszarze niecki deflacyjnej pomiędzy wydmami parabolicznymi na odcinku konińskim Pradoliny Warty. Lokalizacji osadnictwa kultury mogiłowej w pradolinie sprzyjały warunki klimatyczne okresu subborealnego, które określane są jako suche i chłodne. W wyniku badań archeologicznych, litologicznych i geochemicznych stwierdzono, że działalność człowieka przekształciła rzeźbę stanowiska archeologicznego, czyli niecki deflacyjnej. Powstały obiekty archeologiczne, które są pozostałościami działalności osadniczej i gospodarczej (metalurgicznej) zachodzącej na tych samych przestrzeniach stanowiska wielokrotnie. Archiwalne badania palinologiczne wskazują na: obecność wskaźników synantropizacji środowiska, gatunków wprowadzanych przez człowieka, ale też pośrednio na wylesienia, pojawiają się powierzchnie otwarte – pola. Od okresu subborealnego można obserwować nakładanie się wpływów antropogenicznych i naturalnych, klimatycznych kształtujących reżim hydrologiczny w dolinie Warty – można wnioskować o coraz większej częstotliwości powodzi i akumulacji mad. Ten czynnik w konsekwencji mógł się przyczynić do opuszczenia osady około 2800 BP (okres wilgotnych warunków w dolinie).
EN
This article focuses on man-environment relations as exemplified by a Tumulus culture settlement from the Middle Bronze Age discovered in a deflation basin among parabolic dunes in the Konin section of the Warta Pradolina. What favoured the location of the Tumulus culture settlement in the Pradolina was the climatic conditions of the Subboreal period: dry and cool. As archeological, lithological and geochemical studies have shown, human activity has transformed the relief of the archeological site, i.e. the deflation basin. There have appeared archeological objects which are remnants of settlement and economic (metallurgical) activities taking place many times in the same places of the site. Archival palynological research suggests synanthropisation of the environment, the presence of species introduced by man and, indirectly, deforestation: there appeared open spaces – fields. From the Subboreal stage on, one can observe a joint impact of anthropogenic and natural (climatic) factors on the hydrological regime pattern in the Warta valley: a growing frequency of floods and an accumulation of muds. This factor could in effect force people to abandon the settlement about 2800 BP (a period of humid conditions in the valley).
PL
Południowa część Niziny Środkowomazowieckiej wykształcona jest z reguły jako prawie płaska powierzchnia zbudowana z osadów piaszczystych. Została ona określona mianem form stożkopodobnych. Szczegółowa analiza cech teksturalnych wskazała na eoliczne środowisko depozycji osadów. Rozwój form odbywał się w czterech etapach podczas środkowego i górnego vistulianu.
EN
The southern Mazovian Lowland is a almost flat plain build of fine- and medium-grained sands as a rule. It has been described as a fan-like forms. Detailed textural analysis indicated aeolian sedimentary environment. Forms were developed in four phases during middle and upper vistulianu.
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