During geomorphologic mapping of northern seashore of Hornsund (Spitsbergen) a geomorphologic map of Revdalen and Fuglebergsletta was prepared in the scale of 1: 10 000. Distinct outwash routes and a moutonnee area was noted to the south of Rewatnet; at the same time, the destroyed marine terraces in the upper part of the valley and an occurrence of a ground moraine there, prove a Holocene glacier advance in Revdalen (about 2 400 years B. P.). The glaciers of that time slightly overcrossed a zone of the present southern limit of the Rev Lake but they did not fill entirely the middle part of the Revdalen.
Assemblages of molluscs have been used for stratigraphy of Late Glacial and Holocene deposits in Poland. Changes of the climate as well as migration of species are main factors which control the recompositions of molluscan communities in this time. Thirteen malacostratigraphical zones have been definied. Eight of them corresponds with land environments, while the remaining ones (five) with water habitats. The succesions of these zones gives the malacostratigraphical subdivisions, which can be compared with similar schemes proposed in some other countries of Central Europe. They supplement palynostratigraphical zones or even can be used as main way of stratigraphical intrepretations.
This malacological analysis was conducted at a site with peat and calcareous tufas in Łapsze Niżne, Podhale
(southern Poland). The study was carried out in 6 main and several complementary sections, in which 37 mollusc
species were recognized represented by almost 11 000 specimens. The study enabled the reconstruction of
environmental changes during the accumulation of the Holocene deposits (from the Boreal Phase till present).
Conclusions drawn from these reconstructions were compared with results of malacological and palynological
studies from other sites in Podhale. As a result, regional environmental reconstructions for the Holocene of the
area were made. The specific composition, ecological structure and succession of molluscan assemblages from
Łapsze Niżne indicate a significant role for local factors, thus demonstrating the variability of environmental
conditions within a geographic region.
The δ18O data for the last 8000 years in the Greenland NGRIP1, GRIP, DYE-3 and GISP2 ice cores have been analyzed stratigraphically in search of potentially meaningful boundaries and units. Pattern matching of the profiles is supported by using graphical display enhancements, calculating spectral trend curves and generating a compound profile. Techniques routinely used in subsurface geology have been applied in correlating the profiles. Four major stratigraphic units are identified (8.1–4.9, 4.9–3.3, 3.3–1.9 and 1.9–0.1 ka b2k), resulting in an improved understanding of the climate change after the Holocene Climate Optimum. Correlatable higher-order boundaries are identified within these units. The layers between the boundaries show δ18O patterns which generally are similar in character, the differences being ascribed to lateral variations in the factors that control the isotope content of the ice. The layering forms a series of short-lived low-amplitude aperiodic oscillations on a centennial time scale. The suggestion is that these higher-order boundaries and δ18O oscillations have climatic significance. Equivalent units are tentatively identified in ice-core data from the Agassiz and Renland ice caps. Comparison with other climate proxies or stratigraphies from the Northern Hemisphere is expected to render support for the here proposed scheme. It will then serve to guide and constrain the analysis of the dynamics of the climatic fluctuations for the study period.
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 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.
Fructification of Stratiotes aloides L. is very rarely recorded at present. In general, there are only one sex representatives in each lake basin, which simply makes generative reproduction difficult. The subfossil seeds of Stratiotes aloides have been found in five localities of biogenic accumulation in northern and central Poland.
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.